1c942fddfSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later 261e3d0f7SWolfram Sang /* 361e3d0f7SWolfram Sang * Linux I2C core 461e3d0f7SWolfram Sang * 561e3d0f7SWolfram Sang * Copyright (C) 1995-99 Simon G. Vogl 661e3d0f7SWolfram Sang * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> 761e3d0f7SWolfram Sang * Mux support by Rodolfo Giometti <giometti@enneenne.com> and 861e3d0f7SWolfram Sang * Michael Lawnick <michael.lawnick.ext@nsn.com> 961e3d0f7SWolfram Sang * 102f5a55c5SWolfram Sang * Copyright (C) 2013-2017 Wolfram Sang <wsa@kernel.org> 1191ed5349SWolfram Sang */ 1291ed5349SWolfram Sang 1391ed5349SWolfram Sang #define pr_fmt(fmt) "i2c-core: " fmt 1491ed5349SWolfram Sang 1591ed5349SWolfram Sang #include <dt-bindings/i2c/i2c.h> 1691ed5349SWolfram Sang #include <linux/acpi.h> 1791ed5349SWolfram Sang #include <linux/clk/clk-conf.h> 1891ed5349SWolfram Sang #include <linux/completion.h> 1991ed5349SWolfram Sang #include <linux/delay.h> 2091ed5349SWolfram Sang #include <linux/err.h> 2191ed5349SWolfram Sang #include <linux/errno.h> 2210c9ef04SPhil Reid #include <linux/gpio/consumer.h> 2391ed5349SWolfram Sang #include <linux/i2c.h> 24f8756c67SPhil Reid #include <linux/i2c-smbus.h> 2591ed5349SWolfram Sang #include <linux/idr.h> 2691ed5349SWolfram Sang #include <linux/init.h> 2791ed5349SWolfram Sang #include <linux/irqflags.h> 2891ed5349SWolfram Sang #include <linux/jump_label.h> 2991ed5349SWolfram Sang #include <linux/kernel.h> 3091ed5349SWolfram Sang #include <linux/module.h> 3191ed5349SWolfram Sang #include <linux/mutex.h> 3291ed5349SWolfram Sang #include <linux/of_device.h> 3391ed5349SWolfram Sang #include <linux/of.h> 3491ed5349SWolfram Sang #include <linux/of_irq.h> 3575820314SCodrin Ciubotariu #include <linux/pinctrl/consumer.h> 3691ed5349SWolfram Sang #include <linux/pm_domain.h> 3791ed5349SWolfram Sang #include <linux/pm_runtime.h> 3891ed5349SWolfram Sang #include <linux/pm_wakeirq.h> 3991ed5349SWolfram Sang #include <linux/property.h> 4091ed5349SWolfram Sang #include <linux/rwsem.h> 4191ed5349SWolfram Sang #include <linux/slab.h> 4291ed5349SWolfram Sang 4391ed5349SWolfram Sang #include "i2c-core.h" 4491ed5349SWolfram Sang 4591ed5349SWolfram Sang #define CREATE_TRACE_POINTS 4691ed5349SWolfram Sang #include <trace/events/i2c.h> 4791ed5349SWolfram Sang 4891ed5349SWolfram Sang #define I2C_ADDR_OFFSET_TEN_BIT 0xa000 4991ed5349SWolfram Sang #define I2C_ADDR_OFFSET_SLAVE 0x1000 5091ed5349SWolfram Sang 5191ed5349SWolfram Sang #define I2C_ADDR_7BITS_MAX 0x77 5291ed5349SWolfram Sang #define I2C_ADDR_7BITS_COUNT (I2C_ADDR_7BITS_MAX + 1) 5391ed5349SWolfram Sang 54dde67eb1SPeter Rosin #define I2C_ADDR_DEVICE_ID 0x7c 55dde67eb1SPeter Rosin 5661e3d0f7SWolfram Sang /* 5761e3d0f7SWolfram Sang * core_lock protects i2c_adapter_idr, and guarantees that device detection, 580c36dd37SWolfram Sang * deletion of detected devices are serialized 5961e3d0f7SWolfram Sang */ 6091ed5349SWolfram Sang static DEFINE_MUTEX(core_lock); 6191ed5349SWolfram Sang static DEFINE_IDR(i2c_adapter_idr); 6291ed5349SWolfram Sang 6391ed5349SWolfram Sang static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); 6491ed5349SWolfram Sang 6550888b01SDavidlohr Bueso static DEFINE_STATIC_KEY_FALSE(i2c_trace_msg_key); 6691ed5349SWolfram Sang static bool is_registered; 6791ed5349SWolfram Sang 6891ed5349SWolfram Sang int i2c_transfer_trace_reg(void) 6991ed5349SWolfram Sang { 7050888b01SDavidlohr Bueso static_branch_inc(&i2c_trace_msg_key); 7191ed5349SWolfram Sang return 0; 7291ed5349SWolfram Sang } 7391ed5349SWolfram Sang 7491ed5349SWolfram Sang void i2c_transfer_trace_unreg(void) 7591ed5349SWolfram Sang { 7650888b01SDavidlohr Bueso static_branch_dec(&i2c_trace_msg_key); 7791ed5349SWolfram Sang } 7891ed5349SWolfram Sang 793b4c747cSYicong Yang const char *i2c_freq_mode_string(u32 bus_freq_hz) 803b4c747cSYicong Yang { 813b4c747cSYicong Yang switch (bus_freq_hz) { 823b4c747cSYicong Yang case I2C_MAX_STANDARD_MODE_FREQ: 833b4c747cSYicong Yang return "Standard Mode (100 kHz)"; 843b4c747cSYicong Yang case I2C_MAX_FAST_MODE_FREQ: 853b4c747cSYicong Yang return "Fast Mode (400 kHz)"; 863b4c747cSYicong Yang case I2C_MAX_FAST_MODE_PLUS_FREQ: 873b4c747cSYicong Yang return "Fast Mode Plus (1.0 MHz)"; 883b4c747cSYicong Yang case I2C_MAX_TURBO_MODE_FREQ: 893b4c747cSYicong Yang return "Turbo Mode (1.4 MHz)"; 903b4c747cSYicong Yang case I2C_MAX_HIGH_SPEED_MODE_FREQ: 913b4c747cSYicong Yang return "High Speed Mode (3.4 MHz)"; 923b4c747cSYicong Yang case I2C_MAX_ULTRA_FAST_MODE_FREQ: 933b4c747cSYicong Yang return "Ultra Fast Mode (5.0 MHz)"; 943b4c747cSYicong Yang default: 953b4c747cSYicong Yang return "Unknown Mode"; 963b4c747cSYicong Yang } 973b4c747cSYicong Yang } 983b4c747cSYicong Yang EXPORT_SYMBOL_GPL(i2c_freq_mode_string); 993b4c747cSYicong Yang 10091ed5349SWolfram Sang const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, 10191ed5349SWolfram Sang const struct i2c_client *client) 10291ed5349SWolfram Sang { 10391ed5349SWolfram Sang if (!(id && client)) 10491ed5349SWolfram Sang return NULL; 10591ed5349SWolfram Sang 10691ed5349SWolfram Sang while (id->name[0]) { 10791ed5349SWolfram Sang if (strcmp(client->name, id->name) == 0) 10891ed5349SWolfram Sang return id; 10991ed5349SWolfram Sang id++; 11091ed5349SWolfram Sang } 11191ed5349SWolfram Sang return NULL; 11291ed5349SWolfram Sang } 11391ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_match_id); 11491ed5349SWolfram Sang 11591ed5349SWolfram Sang static int i2c_device_match(struct device *dev, struct device_driver *drv) 11691ed5349SWolfram Sang { 11791ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 11891ed5349SWolfram Sang struct i2c_driver *driver; 11991ed5349SWolfram Sang 12091ed5349SWolfram Sang 12191ed5349SWolfram Sang /* Attempt an OF style match */ 12291ed5349SWolfram Sang if (i2c_of_match_device(drv->of_match_table, client)) 12391ed5349SWolfram Sang return 1; 12491ed5349SWolfram Sang 12591ed5349SWolfram Sang /* Then ACPI style match */ 12691ed5349SWolfram Sang if (acpi_driver_match_device(dev, drv)) 12791ed5349SWolfram Sang return 1; 12891ed5349SWolfram Sang 12991ed5349SWolfram Sang driver = to_i2c_driver(drv); 13091ed5349SWolfram Sang 13191ed5349SWolfram Sang /* Finally an I2C match */ 13291ed5349SWolfram Sang if (i2c_match_id(driver->id_table, client)) 13391ed5349SWolfram Sang return 1; 13491ed5349SWolfram Sang 13591ed5349SWolfram Sang return 0; 13691ed5349SWolfram Sang } 13791ed5349SWolfram Sang 13891ed5349SWolfram Sang static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) 13991ed5349SWolfram Sang { 14091ed5349SWolfram Sang struct i2c_client *client = to_i2c_client(dev); 14191ed5349SWolfram Sang int rc; 14291ed5349SWolfram Sang 143af503716SJavier Martinez Canillas rc = of_device_uevent_modalias(dev, env); 144af503716SJavier Martinez Canillas if (rc != -ENODEV) 145af503716SJavier Martinez Canillas return rc; 146af503716SJavier Martinez Canillas 14791ed5349SWolfram Sang rc = acpi_device_uevent_modalias(dev, env); 14891ed5349SWolfram Sang if (rc != -ENODEV) 14991ed5349SWolfram Sang return rc; 15091ed5349SWolfram Sang 15191ed5349SWolfram Sang return add_uevent_var(env, "MODALIAS=%s%s", I2C_MODULE_PREFIX, client->name); 15291ed5349SWolfram Sang } 15391ed5349SWolfram Sang 15491ed5349SWolfram Sang /* i2c bus recovery routines */ 15591ed5349SWolfram Sang static int get_scl_gpio_value(struct i2c_adapter *adap) 15691ed5349SWolfram Sang { 1573991c5c8SPhil Reid return gpiod_get_value_cansleep(adap->bus_recovery_info->scl_gpiod); 15891ed5349SWolfram Sang } 15991ed5349SWolfram Sang 16091ed5349SWolfram Sang static void set_scl_gpio_value(struct i2c_adapter *adap, int val) 16191ed5349SWolfram Sang { 1623991c5c8SPhil Reid gpiod_set_value_cansleep(adap->bus_recovery_info->scl_gpiod, val); 16391ed5349SWolfram Sang } 16491ed5349SWolfram Sang 16591ed5349SWolfram Sang static int get_sda_gpio_value(struct i2c_adapter *adap) 16691ed5349SWolfram Sang { 1673991c5c8SPhil Reid return gpiod_get_value_cansleep(adap->bus_recovery_info->sda_gpiod); 16891ed5349SWolfram Sang } 16991ed5349SWolfram Sang 1708092178fSWolfram Sang static void set_sda_gpio_value(struct i2c_adapter *adap, int val) 17191ed5349SWolfram Sang { 1728092178fSWolfram Sang gpiod_set_value_cansleep(adap->bus_recovery_info->sda_gpiod, val); 17391ed5349SWolfram Sang } 17491ed5349SWolfram Sang 1757ca5f6beSWolfram Sang static int i2c_generic_bus_free(struct i2c_adapter *adap) 1767ca5f6beSWolfram Sang { 1777ca5f6beSWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 1787ca5f6beSWolfram Sang int ret = -EOPNOTSUPP; 1797ca5f6beSWolfram Sang 1807ca5f6beSWolfram Sang if (bri->get_bus_free) 1817ca5f6beSWolfram Sang ret = bri->get_bus_free(adap); 1827ca5f6beSWolfram Sang else if (bri->get_sda) 1837ca5f6beSWolfram Sang ret = bri->get_sda(adap); 1847ca5f6beSWolfram Sang 1857ca5f6beSWolfram Sang if (ret < 0) 1867ca5f6beSWolfram Sang return ret; 1877ca5f6beSWolfram Sang 1887ca5f6beSWolfram Sang return ret ? 0 : -EBUSY; 1897ca5f6beSWolfram Sang } 1907ca5f6beSWolfram Sang 19191ed5349SWolfram Sang /* 19291ed5349SWolfram Sang * We are generating clock pulses. ndelay() determines durating of clk pulses. 19391ed5349SWolfram Sang * We will generate clock with rate 100 KHz and so duration of both clock levels 19491ed5349SWolfram Sang * is: delay in ns = (10^6 / 100) / 2 19591ed5349SWolfram Sang */ 19691ed5349SWolfram Sang #define RECOVERY_NDELAY 5000 19791ed5349SWolfram Sang #define RECOVERY_CLK_CNT 9 19891ed5349SWolfram Sang 199e1eb7d28SPhil Reid int i2c_generic_scl_recovery(struct i2c_adapter *adap) 20091ed5349SWolfram Sang { 20191ed5349SWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 202cf676908SLinus Torvalds int i = 0, scl = 1, ret = 0; 20391ed5349SWolfram Sang 20491ed5349SWolfram Sang if (bri->prepare_recovery) 20591ed5349SWolfram Sang bri->prepare_recovery(adap); 20675820314SCodrin Ciubotariu if (bri->pinctrl) 20775820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_gpio); 20891ed5349SWolfram Sang 209c4ae05b9SWolfram Sang /* 210c4ae05b9SWolfram Sang * If we can set SDA, we will always create a STOP to ensure additional 211c4ae05b9SWolfram Sang * pulses will do no harm. This is achieved by letting SDA follow SCL 212c4ae05b9SWolfram Sang * half a cycle later. Check the 'incomplete_write_byte' fault injector 213cf8ce8b8SRussell King * for details. Note that we must honour tsu:sto, 4us, but lets use 5us 214cf8ce8b8SRussell King * here for simplicity. 215c4ae05b9SWolfram Sang */ 216f7ff75e2SWolfram Sang bri->set_scl(adap, scl); 217cf8ce8b8SRussell King ndelay(RECOVERY_NDELAY); 21872b08fccSWolfram Sang if (bri->set_sda) 219c4ae05b9SWolfram Sang bri->set_sda(adap, scl); 220c4ae05b9SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 22191ed5349SWolfram Sang 22291ed5349SWolfram Sang /* 22391ed5349SWolfram Sang * By this time SCL is high, as we need to give 9 falling-rising edges 22491ed5349SWolfram Sang */ 22591ed5349SWolfram Sang while (i++ < RECOVERY_CLK_CNT * 2) { 226f7ff75e2SWolfram Sang if (scl) { 22791ed5349SWolfram Sang /* SCL shouldn't be low here */ 22891ed5349SWolfram Sang if (!bri->get_scl(adap)) { 22991ed5349SWolfram Sang dev_err(&adap->dev, 23091ed5349SWolfram Sang "SCL is stuck low, exit recovery\n"); 23191ed5349SWolfram Sang ret = -EBUSY; 23291ed5349SWolfram Sang break; 23391ed5349SWolfram Sang } 23491ed5349SWolfram Sang } 23591ed5349SWolfram Sang 236f7ff75e2SWolfram Sang scl = !scl; 237f7ff75e2SWolfram Sang bri->set_scl(adap, scl); 238c4ae05b9SWolfram Sang /* Creating STOP again, see above */ 239cf8ce8b8SRussell King if (scl) { 240cf8ce8b8SRussell King /* Honour minimum tsu:sto */ 241cf8ce8b8SRussell King ndelay(RECOVERY_NDELAY); 242cf8ce8b8SRussell King } else { 243cf8ce8b8SRussell King /* Honour minimum tf and thd:dat */ 244abe41184SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 245cf8ce8b8SRussell King } 246abe41184SWolfram Sang if (bri->set_sda) 247f7ff75e2SWolfram Sang bri->set_sda(adap, scl); 248abe41184SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 2490b71026cSWolfram Sang 250f7ff75e2SWolfram Sang if (scl) { 2517ca5f6beSWolfram Sang ret = i2c_generic_bus_free(adap); 2520b71026cSWolfram Sang if (ret == 0) 2530b71026cSWolfram Sang break; 25491ed5349SWolfram Sang } 25591ed5349SWolfram Sang } 25691ed5349SWolfram Sang 2577ca5f6beSWolfram Sang /* If we can't check bus status, assume recovery worked */ 2587ca5f6beSWolfram Sang if (ret == -EOPNOTSUPP) 2597ca5f6beSWolfram Sang ret = 0; 2602806e6adSWolfram Sang 26191ed5349SWolfram Sang if (bri->unprepare_recovery) 26291ed5349SWolfram Sang bri->unprepare_recovery(adap); 26375820314SCodrin Ciubotariu if (bri->pinctrl) 26475820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_default); 26591ed5349SWolfram Sang 26691ed5349SWolfram Sang return ret; 26791ed5349SWolfram Sang } 26891ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); 26991ed5349SWolfram Sang 27091ed5349SWolfram Sang int i2c_recover_bus(struct i2c_adapter *adap) 27191ed5349SWolfram Sang { 27291ed5349SWolfram Sang if (!adap->bus_recovery_info) 273c126f7c3SDmitry Osipenko return -EBUSY; 27491ed5349SWolfram Sang 27591ed5349SWolfram Sang dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); 27691ed5349SWolfram Sang return adap->bus_recovery_info->recover_bus(adap); 27791ed5349SWolfram Sang } 27891ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_recover_bus); 27991ed5349SWolfram Sang 28075820314SCodrin Ciubotariu static void i2c_gpio_init_pinctrl_recovery(struct i2c_adapter *adap) 28175820314SCodrin Ciubotariu { 28275820314SCodrin Ciubotariu struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 28375820314SCodrin Ciubotariu struct device *dev = &adap->dev; 28475820314SCodrin Ciubotariu struct pinctrl *p = bri->pinctrl; 28575820314SCodrin Ciubotariu 28675820314SCodrin Ciubotariu /* 28775820314SCodrin Ciubotariu * we can't change states without pinctrl, so remove the states if 28875820314SCodrin Ciubotariu * populated 28975820314SCodrin Ciubotariu */ 29075820314SCodrin Ciubotariu if (!p) { 29175820314SCodrin Ciubotariu bri->pins_default = NULL; 29275820314SCodrin Ciubotariu bri->pins_gpio = NULL; 29375820314SCodrin Ciubotariu return; 29475820314SCodrin Ciubotariu } 29575820314SCodrin Ciubotariu 29675820314SCodrin Ciubotariu if (!bri->pins_default) { 29775820314SCodrin Ciubotariu bri->pins_default = pinctrl_lookup_state(p, 29875820314SCodrin Ciubotariu PINCTRL_STATE_DEFAULT); 29975820314SCodrin Ciubotariu if (IS_ERR(bri->pins_default)) { 30075820314SCodrin Ciubotariu dev_dbg(dev, PINCTRL_STATE_DEFAULT " state not found for GPIO recovery\n"); 30175820314SCodrin Ciubotariu bri->pins_default = NULL; 30275820314SCodrin Ciubotariu } 30375820314SCodrin Ciubotariu } 30475820314SCodrin Ciubotariu if (!bri->pins_gpio) { 30575820314SCodrin Ciubotariu bri->pins_gpio = pinctrl_lookup_state(p, "gpio"); 30675820314SCodrin Ciubotariu if (IS_ERR(bri->pins_gpio)) 30775820314SCodrin Ciubotariu bri->pins_gpio = pinctrl_lookup_state(p, "recovery"); 30875820314SCodrin Ciubotariu 30975820314SCodrin Ciubotariu if (IS_ERR(bri->pins_gpio)) { 31075820314SCodrin Ciubotariu dev_dbg(dev, "no gpio or recovery state found for GPIO recovery\n"); 31175820314SCodrin Ciubotariu bri->pins_gpio = NULL; 31275820314SCodrin Ciubotariu } 31375820314SCodrin Ciubotariu } 31475820314SCodrin Ciubotariu 31575820314SCodrin Ciubotariu /* for pinctrl state changes, we need all the information */ 31675820314SCodrin Ciubotariu if (bri->pins_default && bri->pins_gpio) { 31775820314SCodrin Ciubotariu dev_info(dev, "using pinctrl states for GPIO recovery"); 31875820314SCodrin Ciubotariu } else { 31975820314SCodrin Ciubotariu bri->pinctrl = NULL; 32075820314SCodrin Ciubotariu bri->pins_default = NULL; 32175820314SCodrin Ciubotariu bri->pins_gpio = NULL; 32275820314SCodrin Ciubotariu } 32375820314SCodrin Ciubotariu } 32475820314SCodrin Ciubotariu 32575820314SCodrin Ciubotariu static int i2c_gpio_init_generic_recovery(struct i2c_adapter *adap) 32675820314SCodrin Ciubotariu { 32775820314SCodrin Ciubotariu struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 32875820314SCodrin Ciubotariu struct device *dev = &adap->dev; 32975820314SCodrin Ciubotariu struct gpio_desc *gpiod; 33075820314SCodrin Ciubotariu int ret = 0; 33175820314SCodrin Ciubotariu 33275820314SCodrin Ciubotariu /* 33375820314SCodrin Ciubotariu * don't touch the recovery information if the driver is not using 33475820314SCodrin Ciubotariu * generic SCL recovery 33575820314SCodrin Ciubotariu */ 33675820314SCodrin Ciubotariu if (bri->recover_bus && bri->recover_bus != i2c_generic_scl_recovery) 33775820314SCodrin Ciubotariu return 0; 33875820314SCodrin Ciubotariu 33975820314SCodrin Ciubotariu /* 34075820314SCodrin Ciubotariu * pins might be taken as GPIO, so we should inform pinctrl about 34175820314SCodrin Ciubotariu * this and move the state to GPIO 34275820314SCodrin Ciubotariu */ 34375820314SCodrin Ciubotariu if (bri->pinctrl) 34475820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_gpio); 34575820314SCodrin Ciubotariu 34675820314SCodrin Ciubotariu /* 34775820314SCodrin Ciubotariu * if there is incomplete or no recovery information, see if generic 34875820314SCodrin Ciubotariu * GPIO recovery is available 34975820314SCodrin Ciubotariu */ 35075820314SCodrin Ciubotariu if (!bri->scl_gpiod) { 35175820314SCodrin Ciubotariu gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); 35275820314SCodrin Ciubotariu if (PTR_ERR(gpiod) == -EPROBE_DEFER) { 35375820314SCodrin Ciubotariu ret = -EPROBE_DEFER; 35475820314SCodrin Ciubotariu goto cleanup_pinctrl_state; 35575820314SCodrin Ciubotariu } 35675820314SCodrin Ciubotariu if (!IS_ERR(gpiod)) { 35775820314SCodrin Ciubotariu bri->scl_gpiod = gpiod; 35875820314SCodrin Ciubotariu bri->recover_bus = i2c_generic_scl_recovery; 35975820314SCodrin Ciubotariu dev_info(dev, "using generic GPIOs for recovery\n"); 36075820314SCodrin Ciubotariu } 36175820314SCodrin Ciubotariu } 36275820314SCodrin Ciubotariu 36375820314SCodrin Ciubotariu /* SDA GPIOD line is optional, so we care about DEFER only */ 36475820314SCodrin Ciubotariu if (!bri->sda_gpiod) { 36575820314SCodrin Ciubotariu /* 36675820314SCodrin Ciubotariu * We have SCL. Pull SCL low and wait a bit so that SDA glitches 36775820314SCodrin Ciubotariu * have no effect. 36875820314SCodrin Ciubotariu */ 36975820314SCodrin Ciubotariu gpiod_direction_output(bri->scl_gpiod, 0); 37075820314SCodrin Ciubotariu udelay(10); 37175820314SCodrin Ciubotariu gpiod = devm_gpiod_get(dev, "sda", GPIOD_IN); 37275820314SCodrin Ciubotariu 37375820314SCodrin Ciubotariu /* Wait a bit in case of a SDA glitch, and then release SCL. */ 37475820314SCodrin Ciubotariu udelay(10); 37575820314SCodrin Ciubotariu gpiod_direction_output(bri->scl_gpiod, 1); 37675820314SCodrin Ciubotariu 37775820314SCodrin Ciubotariu if (PTR_ERR(gpiod) == -EPROBE_DEFER) { 37875820314SCodrin Ciubotariu ret = -EPROBE_DEFER; 37975820314SCodrin Ciubotariu goto cleanup_pinctrl_state; 38075820314SCodrin Ciubotariu } 38175820314SCodrin Ciubotariu if (!IS_ERR(gpiod)) 38275820314SCodrin Ciubotariu bri->sda_gpiod = gpiod; 38375820314SCodrin Ciubotariu } 38475820314SCodrin Ciubotariu 38575820314SCodrin Ciubotariu cleanup_pinctrl_state: 38675820314SCodrin Ciubotariu /* change the state of the pins back to their default state */ 38775820314SCodrin Ciubotariu if (bri->pinctrl) 38875820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_default); 38975820314SCodrin Ciubotariu 39075820314SCodrin Ciubotariu return ret; 39175820314SCodrin Ciubotariu } 39275820314SCodrin Ciubotariu 39375820314SCodrin Ciubotariu static int i2c_gpio_init_recovery(struct i2c_adapter *adap) 39475820314SCodrin Ciubotariu { 39575820314SCodrin Ciubotariu i2c_gpio_init_pinctrl_recovery(adap); 39675820314SCodrin Ciubotariu return i2c_gpio_init_generic_recovery(adap); 39775820314SCodrin Ciubotariu } 39875820314SCodrin Ciubotariu 39923a698feSCodrin Ciubotariu static int i2c_init_recovery(struct i2c_adapter *adap) 40091ed5349SWolfram Sang { 40191ed5349SWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 402*cb3c66afSAndy Shevchenko bool is_error_level = true; 403*cb3c66afSAndy Shevchenko char *err_str; 40491ed5349SWolfram Sang 40591ed5349SWolfram Sang if (!bri) 40623a698feSCodrin Ciubotariu return 0; 40791ed5349SWolfram Sang 40823a698feSCodrin Ciubotariu if (i2c_gpio_init_recovery(adap) == -EPROBE_DEFER) 40923a698feSCodrin Ciubotariu return -EPROBE_DEFER; 41075820314SCodrin Ciubotariu 41191ed5349SWolfram Sang if (!bri->recover_bus) { 412e409a6a3SWolfram Sang err_str = "no suitable method provided"; 413*cb3c66afSAndy Shevchenko is_error_level = false; 41491ed5349SWolfram Sang goto err; 41591ed5349SWolfram Sang } 41691ed5349SWolfram Sang 4173991c5c8SPhil Reid if (bri->scl_gpiod && bri->recover_bus == i2c_generic_scl_recovery) { 41891ed5349SWolfram Sang bri->get_scl = get_scl_gpio_value; 41991ed5349SWolfram Sang bri->set_scl = set_scl_gpio_value; 4208092178fSWolfram Sang if (bri->sda_gpiod) { 4213991c5c8SPhil Reid bri->get_sda = get_sda_gpio_value; 4228092178fSWolfram Sang /* FIXME: add proper flag instead of '0' once available */ 4238092178fSWolfram Sang if (gpiod_get_direction(bri->sda_gpiod) == 0) 4248092178fSWolfram Sang bri->set_sda = set_sda_gpio_value; 4258092178fSWolfram Sang } 42623a698feSCodrin Ciubotariu } else if (bri->recover_bus == i2c_generic_scl_recovery) { 42791ed5349SWolfram Sang /* Generic SCL recovery */ 42891ed5349SWolfram Sang if (!bri->set_scl || !bri->get_scl) { 42991ed5349SWolfram Sang err_str = "no {get|set}_scl() found"; 43091ed5349SWolfram Sang goto err; 43191ed5349SWolfram Sang } 432ffc59c49SWolfram Sang if (!bri->set_sda && !bri->get_sda) { 433ffc59c49SWolfram Sang err_str = "either get_sda() or set_sda() needed"; 434ffc59c49SWolfram Sang goto err; 435ffc59c49SWolfram Sang } 43691ed5349SWolfram Sang } 43791ed5349SWolfram Sang 43823a698feSCodrin Ciubotariu return 0; 43991ed5349SWolfram Sang err: 440*cb3c66afSAndy Shevchenko if (is_error_level) 441*cb3c66afSAndy Shevchenko dev_err(&adap->dev, "Not using recovery: %s\n", err_str); 442*cb3c66afSAndy Shevchenko else 443*cb3c66afSAndy Shevchenko dev_dbg(&adap->dev, "Not using recovery: %s\n", err_str); 44491ed5349SWolfram Sang adap->bus_recovery_info = NULL; 44523a698feSCodrin Ciubotariu 44623a698feSCodrin Ciubotariu return -EINVAL; 44791ed5349SWolfram Sang } 44891ed5349SWolfram Sang 44991ed5349SWolfram Sang static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) 45091ed5349SWolfram Sang { 45191ed5349SWolfram Sang struct i2c_adapter *adap = client->adapter; 45291ed5349SWolfram Sang unsigned int irq; 45391ed5349SWolfram Sang 45491ed5349SWolfram Sang if (!adap->host_notify_domain) 45591ed5349SWolfram Sang return -ENXIO; 45691ed5349SWolfram Sang 45791ed5349SWolfram Sang if (client->flags & I2C_CLIENT_TEN) 45891ed5349SWolfram Sang return -EINVAL; 45991ed5349SWolfram Sang 460b9bb3fdfSCharles Keepax irq = irq_create_mapping(adap->host_notify_domain, client->addr); 46191ed5349SWolfram Sang 46291ed5349SWolfram Sang return irq > 0 ? irq : -ENXIO; 46391ed5349SWolfram Sang } 46491ed5349SWolfram Sang 46591ed5349SWolfram Sang static int i2c_device_probe(struct device *dev) 46691ed5349SWolfram Sang { 46791ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 46891ed5349SWolfram Sang struct i2c_driver *driver; 46991ed5349SWolfram Sang int status; 47091ed5349SWolfram Sang 47191ed5349SWolfram Sang if (!client) 47291ed5349SWolfram Sang return 0; 47391ed5349SWolfram Sang 4746e76cb7dSCharles Keepax client->irq = client->init_irq; 4756e76cb7dSCharles Keepax 4760c2a3493SWolfram Sang if (!client->irq) { 47791ed5349SWolfram Sang int irq = -ENOENT; 47891ed5349SWolfram Sang 47991ed5349SWolfram Sang if (client->flags & I2C_CLIENT_HOST_NOTIFY) { 48091ed5349SWolfram Sang dev_dbg(dev, "Using Host Notify IRQ\n"); 48172bfcee1SJarkko Nikula /* Keep adapter active when Host Notify is required */ 48272bfcee1SJarkko Nikula pm_runtime_get_sync(&client->adapter->dev); 48391ed5349SWolfram Sang irq = i2c_smbus_host_notify_to_irq(client); 48491ed5349SWolfram Sang } else if (dev->of_node) { 48591ed5349SWolfram Sang irq = of_irq_get_byname(dev->of_node, "irq"); 48691ed5349SWolfram Sang if (irq == -EINVAL || irq == -ENODATA) 48791ed5349SWolfram Sang irq = of_irq_get(dev->of_node, 0); 48891ed5349SWolfram Sang } else if (ACPI_COMPANION(dev)) { 48916c9db1dSCharles Keepax irq = i2c_acpi_get_irq(client); 49091ed5349SWolfram Sang } 4913c3dd56fSAlain Volmat if (irq == -EPROBE_DEFER) { 4923c3dd56fSAlain Volmat status = irq; 4933c3dd56fSAlain Volmat goto put_sync_adapter; 4943c3dd56fSAlain Volmat } 49591ed5349SWolfram Sang 49691ed5349SWolfram Sang if (irq < 0) 49791ed5349SWolfram Sang irq = 0; 49891ed5349SWolfram Sang 49991ed5349SWolfram Sang client->irq = irq; 50091ed5349SWolfram Sang } 50191ed5349SWolfram Sang 5020c2a3493SWolfram Sang driver = to_i2c_driver(dev->driver); 5030c2a3493SWolfram Sang 50491ed5349SWolfram Sang /* 505f4b17a14SJavier Martinez Canillas * An I2C ID table is not mandatory, if and only if, a suitable OF 506f4b17a14SJavier Martinez Canillas * or ACPI ID table is supplied for the probing device. 50791ed5349SWolfram Sang */ 50891ed5349SWolfram Sang if (!driver->id_table && 509e3cb82c6SAndy Shevchenko !acpi_driver_match_device(dev, dev->driver) && 5103c3dd56fSAlain Volmat !i2c_of_match_device(dev->driver->of_match_table, client)) { 5113c3dd56fSAlain Volmat status = -ENODEV; 5123c3dd56fSAlain Volmat goto put_sync_adapter; 5133c3dd56fSAlain Volmat } 51491ed5349SWolfram Sang 51591ed5349SWolfram Sang if (client->flags & I2C_CLIENT_WAKE) { 5163e99834cSAndy Shevchenko int wakeirq; 51791ed5349SWolfram Sang 51891ed5349SWolfram Sang wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); 5193c3dd56fSAlain Volmat if (wakeirq == -EPROBE_DEFER) { 5203c3dd56fSAlain Volmat status = wakeirq; 5213c3dd56fSAlain Volmat goto put_sync_adapter; 5223c3dd56fSAlain Volmat } 52391ed5349SWolfram Sang 52491ed5349SWolfram Sang device_init_wakeup(&client->dev, true); 52591ed5349SWolfram Sang 52691ed5349SWolfram Sang if (wakeirq > 0 && wakeirq != client->irq) 52791ed5349SWolfram Sang status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); 52891ed5349SWolfram Sang else if (client->irq > 0) 52991ed5349SWolfram Sang status = dev_pm_set_wake_irq(dev, client->irq); 53091ed5349SWolfram Sang else 53191ed5349SWolfram Sang status = 0; 53291ed5349SWolfram Sang 53391ed5349SWolfram Sang if (status) 53491ed5349SWolfram Sang dev_warn(&client->dev, "failed to set up wakeup irq\n"); 53591ed5349SWolfram Sang } 53691ed5349SWolfram Sang 53791ed5349SWolfram Sang dev_dbg(dev, "probe\n"); 53891ed5349SWolfram Sang 53991ed5349SWolfram Sang status = of_clk_set_defaults(dev->of_node, false); 54091ed5349SWolfram Sang if (status < 0) 54191ed5349SWolfram Sang goto err_clear_wakeup_irq; 54291ed5349SWolfram Sang 54391ed5349SWolfram Sang status = dev_pm_domain_attach(&client->dev, true); 544e6a20b6cSUlf Hansson if (status) 54591ed5349SWolfram Sang goto err_clear_wakeup_irq; 54691ed5349SWolfram Sang 5475b547582SDmitry Torokhov client->devres_group_id = devres_open_group(&client->dev, NULL, 5485b547582SDmitry Torokhov GFP_KERNEL); 5495b547582SDmitry Torokhov if (!client->devres_group_id) { 5505b547582SDmitry Torokhov status = -ENOMEM; 5515b547582SDmitry Torokhov goto err_detach_pm_domain; 5525b547582SDmitry Torokhov } 5535b547582SDmitry Torokhov 55491ed5349SWolfram Sang /* 55591ed5349SWolfram Sang * When there are no more users of probe(), 55691ed5349SWolfram Sang * rename probe_new to probe. 55791ed5349SWolfram Sang */ 55891ed5349SWolfram Sang if (driver->probe_new) 55991ed5349SWolfram Sang status = driver->probe_new(client); 56091ed5349SWolfram Sang else if (driver->probe) 56191ed5349SWolfram Sang status = driver->probe(client, 56291ed5349SWolfram Sang i2c_match_id(driver->id_table, client)); 56391ed5349SWolfram Sang else 56491ed5349SWolfram Sang status = -EINVAL; 56591ed5349SWolfram Sang 5665b547582SDmitry Torokhov /* 5675b547582SDmitry Torokhov * Note that we are not closing the devres group opened above so 5685b547582SDmitry Torokhov * even resources that were attached to the device after probe is 5695b547582SDmitry Torokhov * run are released when i2c_device_remove() is executed. This is 5705b547582SDmitry Torokhov * needed as some drivers would allocate additional resources, 5715b547582SDmitry Torokhov * for example when updating firmware. 5725b547582SDmitry Torokhov */ 5735b547582SDmitry Torokhov 57491ed5349SWolfram Sang if (status) 5755b547582SDmitry Torokhov goto err_release_driver_resources; 57691ed5349SWolfram Sang 57791ed5349SWolfram Sang return 0; 57891ed5349SWolfram Sang 5795b547582SDmitry Torokhov err_release_driver_resources: 5805b547582SDmitry Torokhov devres_release_group(&client->dev, client->devres_group_id); 58191ed5349SWolfram Sang err_detach_pm_domain: 58291ed5349SWolfram Sang dev_pm_domain_detach(&client->dev, true); 58391ed5349SWolfram Sang err_clear_wakeup_irq: 58491ed5349SWolfram Sang dev_pm_clear_wake_irq(&client->dev); 58591ed5349SWolfram Sang device_init_wakeup(&client->dev, false); 5863c3dd56fSAlain Volmat put_sync_adapter: 5873c3dd56fSAlain Volmat if (client->flags & I2C_CLIENT_HOST_NOTIFY) 5883c3dd56fSAlain Volmat pm_runtime_put_sync(&client->adapter->dev); 5893c3dd56fSAlain Volmat 59091ed5349SWolfram Sang return status; 59191ed5349SWolfram Sang } 59291ed5349SWolfram Sang 59391ed5349SWolfram Sang static int i2c_device_remove(struct device *dev) 59491ed5349SWolfram Sang { 5954e970a0aSUwe Kleine-König struct i2c_client *client = to_i2c_client(dev); 59691ed5349SWolfram Sang struct i2c_driver *driver; 59791ed5349SWolfram Sang 59891ed5349SWolfram Sang driver = to_i2c_driver(dev->driver); 59991ed5349SWolfram Sang if (driver->remove) { 60071637c62SUwe Kleine-König int status; 60171637c62SUwe Kleine-König 60291ed5349SWolfram Sang dev_dbg(dev, "remove\n"); 60371637c62SUwe Kleine-König 60491ed5349SWolfram Sang status = driver->remove(client); 60571637c62SUwe Kleine-König if (status) 60671637c62SUwe Kleine-König dev_warn(dev, "remove failed (%pe), will be ignored\n", ERR_PTR(status)); 60791ed5349SWolfram Sang } 60891ed5349SWolfram Sang 6095b547582SDmitry Torokhov devres_release_group(&client->dev, client->devres_group_id); 6105b547582SDmitry Torokhov 61191ed5349SWolfram Sang dev_pm_domain_detach(&client->dev, true); 61291ed5349SWolfram Sang 61391ed5349SWolfram Sang dev_pm_clear_wake_irq(&client->dev); 61491ed5349SWolfram Sang device_init_wakeup(&client->dev, false); 61591ed5349SWolfram Sang 6166e76cb7dSCharles Keepax client->irq = 0; 61772bfcee1SJarkko Nikula if (client->flags & I2C_CLIENT_HOST_NOTIFY) 61872bfcee1SJarkko Nikula pm_runtime_put(&client->adapter->dev); 6196f108dd7SCharles Keepax 62071637c62SUwe Kleine-König /* return always 0 because there is WIP to make remove-functions void */ 62171637c62SUwe Kleine-König return 0; 62291ed5349SWolfram Sang } 62391ed5349SWolfram Sang 62491ed5349SWolfram Sang static void i2c_device_shutdown(struct device *dev) 62591ed5349SWolfram Sang { 62691ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 62791ed5349SWolfram Sang struct i2c_driver *driver; 62891ed5349SWolfram Sang 62991ed5349SWolfram Sang if (!client || !dev->driver) 63091ed5349SWolfram Sang return; 63191ed5349SWolfram Sang driver = to_i2c_driver(dev->driver); 63291ed5349SWolfram Sang if (driver->shutdown) 63391ed5349SWolfram Sang driver->shutdown(client); 63491ed5349SWolfram Sang } 63591ed5349SWolfram Sang 63691ed5349SWolfram Sang static void i2c_client_dev_release(struct device *dev) 63791ed5349SWolfram Sang { 63891ed5349SWolfram Sang kfree(to_i2c_client(dev)); 63991ed5349SWolfram Sang } 64091ed5349SWolfram Sang 64191ed5349SWolfram Sang static ssize_t 64254a19fd4SGeert Uytterhoeven name_show(struct device *dev, struct device_attribute *attr, char *buf) 64391ed5349SWolfram Sang { 64491ed5349SWolfram Sang return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? 64591ed5349SWolfram Sang to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); 64691ed5349SWolfram Sang } 64754a19fd4SGeert Uytterhoeven static DEVICE_ATTR_RO(name); 64891ed5349SWolfram Sang 64991ed5349SWolfram Sang static ssize_t 65054a19fd4SGeert Uytterhoeven modalias_show(struct device *dev, struct device_attribute *attr, char *buf) 65191ed5349SWolfram Sang { 65291ed5349SWolfram Sang struct i2c_client *client = to_i2c_client(dev); 65391ed5349SWolfram Sang int len; 65491ed5349SWolfram Sang 655af503716SJavier Martinez Canillas len = of_device_modalias(dev, buf, PAGE_SIZE); 656af503716SJavier Martinez Canillas if (len != -ENODEV) 657af503716SJavier Martinez Canillas return len; 658af503716SJavier Martinez Canillas 65991ed5349SWolfram Sang len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1); 66091ed5349SWolfram Sang if (len != -ENODEV) 66191ed5349SWolfram Sang return len; 66291ed5349SWolfram Sang 66391ed5349SWolfram Sang return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); 66491ed5349SWolfram Sang } 66554a19fd4SGeert Uytterhoeven static DEVICE_ATTR_RO(modalias); 66691ed5349SWolfram Sang 66791ed5349SWolfram Sang static struct attribute *i2c_dev_attrs[] = { 66891ed5349SWolfram Sang &dev_attr_name.attr, 66991ed5349SWolfram Sang /* modalias helps coldplug: modprobe $(cat .../modalias) */ 67091ed5349SWolfram Sang &dev_attr_modalias.attr, 67191ed5349SWolfram Sang NULL 67291ed5349SWolfram Sang }; 67391ed5349SWolfram Sang ATTRIBUTE_GROUPS(i2c_dev); 67491ed5349SWolfram Sang 67591ed5349SWolfram Sang struct bus_type i2c_bus_type = { 67691ed5349SWolfram Sang .name = "i2c", 67791ed5349SWolfram Sang .match = i2c_device_match, 67891ed5349SWolfram Sang .probe = i2c_device_probe, 67991ed5349SWolfram Sang .remove = i2c_device_remove, 68091ed5349SWolfram Sang .shutdown = i2c_device_shutdown, 68191ed5349SWolfram Sang }; 68291ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_bus_type); 68391ed5349SWolfram Sang 68491ed5349SWolfram Sang struct device_type i2c_client_type = { 68591ed5349SWolfram Sang .groups = i2c_dev_groups, 68691ed5349SWolfram Sang .uevent = i2c_device_uevent, 68791ed5349SWolfram Sang .release = i2c_client_dev_release, 68891ed5349SWolfram Sang }; 68991ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_client_type); 69091ed5349SWolfram Sang 69191ed5349SWolfram Sang 69291ed5349SWolfram Sang /** 69391ed5349SWolfram Sang * i2c_verify_client - return parameter as i2c_client, or NULL 69491ed5349SWolfram Sang * @dev: device, probably from some driver model iterator 69591ed5349SWolfram Sang * 69691ed5349SWolfram Sang * When traversing the driver model tree, perhaps using driver model 69791ed5349SWolfram Sang * iterators like @device_for_each_child(), you can't assume very much 69891ed5349SWolfram Sang * about the nodes you find. Use this function to avoid oopses caused 69991ed5349SWolfram Sang * by wrongly treating some non-I2C device as an i2c_client. 70091ed5349SWolfram Sang */ 70191ed5349SWolfram Sang struct i2c_client *i2c_verify_client(struct device *dev) 70291ed5349SWolfram Sang { 70391ed5349SWolfram Sang return (dev->type == &i2c_client_type) 70491ed5349SWolfram Sang ? to_i2c_client(dev) 70591ed5349SWolfram Sang : NULL; 70691ed5349SWolfram Sang } 70791ed5349SWolfram Sang EXPORT_SYMBOL(i2c_verify_client); 70891ed5349SWolfram Sang 70991ed5349SWolfram Sang 71091ed5349SWolfram Sang /* Return a unique address which takes the flags of the client into account */ 71191ed5349SWolfram Sang static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) 71291ed5349SWolfram Sang { 71391ed5349SWolfram Sang unsigned short addr = client->addr; 71491ed5349SWolfram Sang 71591ed5349SWolfram Sang /* For some client flags, add an arbitrary offset to avoid collisions */ 71691ed5349SWolfram Sang if (client->flags & I2C_CLIENT_TEN) 71791ed5349SWolfram Sang addr |= I2C_ADDR_OFFSET_TEN_BIT; 71891ed5349SWolfram Sang 71991ed5349SWolfram Sang if (client->flags & I2C_CLIENT_SLAVE) 72091ed5349SWolfram Sang addr |= I2C_ADDR_OFFSET_SLAVE; 72191ed5349SWolfram Sang 72291ed5349SWolfram Sang return addr; 72391ed5349SWolfram Sang } 72491ed5349SWolfram Sang 72591ed5349SWolfram Sang /* This is a permissive address validity check, I2C address map constraints 72691ed5349SWolfram Sang * are purposely not enforced, except for the general call address. */ 727398432edSWolfram Sang static int i2c_check_addr_validity(unsigned int addr, unsigned short flags) 72891ed5349SWolfram Sang { 72991ed5349SWolfram Sang if (flags & I2C_CLIENT_TEN) { 73091ed5349SWolfram Sang /* 10-bit address, all values are valid */ 73191ed5349SWolfram Sang if (addr > 0x3ff) 73291ed5349SWolfram Sang return -EINVAL; 73391ed5349SWolfram Sang } else { 73491ed5349SWolfram Sang /* 7-bit address, reject the general call address */ 73591ed5349SWolfram Sang if (addr == 0x00 || addr > 0x7f) 73691ed5349SWolfram Sang return -EINVAL; 73791ed5349SWolfram Sang } 73891ed5349SWolfram Sang return 0; 73991ed5349SWolfram Sang } 74091ed5349SWolfram Sang 74191ed5349SWolfram Sang /* And this is a strict address validity check, used when probing. If a 74291ed5349SWolfram Sang * device uses a reserved address, then it shouldn't be probed. 7-bit 74391ed5349SWolfram Sang * addressing is assumed, 10-bit address devices are rare and should be 74491ed5349SWolfram Sang * explicitly enumerated. */ 745e4991ecdSWolfram Sang int i2c_check_7bit_addr_validity_strict(unsigned short addr) 74691ed5349SWolfram Sang { 74791ed5349SWolfram Sang /* 74891ed5349SWolfram Sang * Reserved addresses per I2C specification: 74991ed5349SWolfram Sang * 0x00 General call address / START byte 75091ed5349SWolfram Sang * 0x01 CBUS address 75191ed5349SWolfram Sang * 0x02 Reserved for different bus format 75291ed5349SWolfram Sang * 0x03 Reserved for future purposes 75391ed5349SWolfram Sang * 0x04-0x07 Hs-mode master code 75491ed5349SWolfram Sang * 0x78-0x7b 10-bit slave addressing 75591ed5349SWolfram Sang * 0x7c-0x7f Reserved for future purposes 75691ed5349SWolfram Sang */ 75791ed5349SWolfram Sang if (addr < 0x08 || addr > 0x77) 75891ed5349SWolfram Sang return -EINVAL; 75991ed5349SWolfram Sang return 0; 76091ed5349SWolfram Sang } 76191ed5349SWolfram Sang 76291ed5349SWolfram Sang static int __i2c_check_addr_busy(struct device *dev, void *addrp) 76391ed5349SWolfram Sang { 76491ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 76591ed5349SWolfram Sang int addr = *(int *)addrp; 76691ed5349SWolfram Sang 76791ed5349SWolfram Sang if (client && i2c_encode_flags_to_addr(client) == addr) 76891ed5349SWolfram Sang return -EBUSY; 76991ed5349SWolfram Sang return 0; 77091ed5349SWolfram Sang } 77191ed5349SWolfram Sang 77291ed5349SWolfram Sang /* walk up mux tree */ 77391ed5349SWolfram Sang static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) 77491ed5349SWolfram Sang { 77591ed5349SWolfram Sang struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); 77691ed5349SWolfram Sang int result; 77791ed5349SWolfram Sang 77891ed5349SWolfram Sang result = device_for_each_child(&adapter->dev, &addr, 77991ed5349SWolfram Sang __i2c_check_addr_busy); 78091ed5349SWolfram Sang 78191ed5349SWolfram Sang if (!result && parent) 78291ed5349SWolfram Sang result = i2c_check_mux_parents(parent, addr); 78391ed5349SWolfram Sang 78491ed5349SWolfram Sang return result; 78591ed5349SWolfram Sang } 78691ed5349SWolfram Sang 78791ed5349SWolfram Sang /* recurse down mux tree */ 78891ed5349SWolfram Sang static int i2c_check_mux_children(struct device *dev, void *addrp) 78991ed5349SWolfram Sang { 79091ed5349SWolfram Sang int result; 79191ed5349SWolfram Sang 79291ed5349SWolfram Sang if (dev->type == &i2c_adapter_type) 79391ed5349SWolfram Sang result = device_for_each_child(dev, addrp, 79491ed5349SWolfram Sang i2c_check_mux_children); 79591ed5349SWolfram Sang else 79691ed5349SWolfram Sang result = __i2c_check_addr_busy(dev, addrp); 79791ed5349SWolfram Sang 79891ed5349SWolfram Sang return result; 79991ed5349SWolfram Sang } 80091ed5349SWolfram Sang 80191ed5349SWolfram Sang static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) 80291ed5349SWolfram Sang { 80391ed5349SWolfram Sang struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); 80491ed5349SWolfram Sang int result = 0; 80591ed5349SWolfram Sang 80691ed5349SWolfram Sang if (parent) 80791ed5349SWolfram Sang result = i2c_check_mux_parents(parent, addr); 80891ed5349SWolfram Sang 80991ed5349SWolfram Sang if (!result) 81091ed5349SWolfram Sang result = device_for_each_child(&adapter->dev, &addr, 81191ed5349SWolfram Sang i2c_check_mux_children); 81291ed5349SWolfram Sang 81391ed5349SWolfram Sang return result; 81491ed5349SWolfram Sang } 81591ed5349SWolfram Sang 81691ed5349SWolfram Sang /** 81791ed5349SWolfram Sang * i2c_adapter_lock_bus - Get exclusive access to an I2C bus segment 81891ed5349SWolfram Sang * @adapter: Target I2C bus segment 81991ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT 82091ed5349SWolfram Sang * locks only this branch in the adapter tree 82191ed5349SWolfram Sang */ 82291ed5349SWolfram Sang static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, 82391ed5349SWolfram Sang unsigned int flags) 82491ed5349SWolfram Sang { 8257b94ea50SPeter Rosin rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter)); 82691ed5349SWolfram Sang } 82791ed5349SWolfram Sang 82891ed5349SWolfram Sang /** 82991ed5349SWolfram Sang * i2c_adapter_trylock_bus - Try to get exclusive access to an I2C bus segment 83091ed5349SWolfram Sang * @adapter: Target I2C bus segment 83191ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER trylocks the root i2c adapter, I2C_LOCK_SEGMENT 83291ed5349SWolfram Sang * trylocks only this branch in the adapter tree 83391ed5349SWolfram Sang */ 83491ed5349SWolfram Sang static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, 83591ed5349SWolfram Sang unsigned int flags) 83691ed5349SWolfram Sang { 83791ed5349SWolfram Sang return rt_mutex_trylock(&adapter->bus_lock); 83891ed5349SWolfram Sang } 83991ed5349SWolfram Sang 84091ed5349SWolfram Sang /** 84191ed5349SWolfram Sang * i2c_adapter_unlock_bus - Release exclusive access to an I2C bus segment 84291ed5349SWolfram Sang * @adapter: Target I2C bus segment 84391ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT 84491ed5349SWolfram Sang * unlocks only this branch in the adapter tree 84591ed5349SWolfram Sang */ 84691ed5349SWolfram Sang static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, 84791ed5349SWolfram Sang unsigned int flags) 84891ed5349SWolfram Sang { 84991ed5349SWolfram Sang rt_mutex_unlock(&adapter->bus_lock); 85091ed5349SWolfram Sang } 85191ed5349SWolfram Sang 85291ed5349SWolfram Sang static void i2c_dev_set_name(struct i2c_adapter *adap, 853728fe6ceSHans de Goede struct i2c_client *client, 854728fe6ceSHans de Goede struct i2c_board_info const *info) 85591ed5349SWolfram Sang { 85691ed5349SWolfram Sang struct acpi_device *adev = ACPI_COMPANION(&client->dev); 85791ed5349SWolfram Sang 858728fe6ceSHans de Goede if (info && info->dev_name) { 859728fe6ceSHans de Goede dev_set_name(&client->dev, "i2c-%s", info->dev_name); 860728fe6ceSHans de Goede return; 861728fe6ceSHans de Goede } 862728fe6ceSHans de Goede 86391ed5349SWolfram Sang if (adev) { 86491ed5349SWolfram Sang dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); 86591ed5349SWolfram Sang return; 86691ed5349SWolfram Sang } 86791ed5349SWolfram Sang 86891ed5349SWolfram Sang dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), 86991ed5349SWolfram Sang i2c_encode_flags_to_addr(client)); 87091ed5349SWolfram Sang } 87191ed5349SWolfram Sang 8721d7534b6SCharles Keepax int i2c_dev_irq_from_resources(const struct resource *resources, 87391ed5349SWolfram Sang unsigned int num_resources) 87491ed5349SWolfram Sang { 87591ed5349SWolfram Sang struct irq_data *irqd; 87691ed5349SWolfram Sang int i; 87791ed5349SWolfram Sang 87891ed5349SWolfram Sang for (i = 0; i < num_resources; i++) { 87991ed5349SWolfram Sang const struct resource *r = &resources[i]; 88091ed5349SWolfram Sang 88191ed5349SWolfram Sang if (resource_type(r) != IORESOURCE_IRQ) 88291ed5349SWolfram Sang continue; 88391ed5349SWolfram Sang 88491ed5349SWolfram Sang if (r->flags & IORESOURCE_BITS) { 88591ed5349SWolfram Sang irqd = irq_get_irq_data(r->start); 88691ed5349SWolfram Sang if (!irqd) 88791ed5349SWolfram Sang break; 88891ed5349SWolfram Sang 88991ed5349SWolfram Sang irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS); 89091ed5349SWolfram Sang } 89191ed5349SWolfram Sang 89291ed5349SWolfram Sang return r->start; 89391ed5349SWolfram Sang } 89491ed5349SWolfram Sang 89591ed5349SWolfram Sang return 0; 89691ed5349SWolfram Sang } 89791ed5349SWolfram Sang 89891ed5349SWolfram Sang /** 8997159dbdaSHeiner Kallweit * i2c_new_client_device - instantiate an i2c device 90091ed5349SWolfram Sang * @adap: the adapter managing the device 90191ed5349SWolfram Sang * @info: describes one I2C device; bus_num is ignored 90291ed5349SWolfram Sang * Context: can sleep 90391ed5349SWolfram Sang * 90491ed5349SWolfram Sang * Create an i2c device. Binding is handled through driver model 90591ed5349SWolfram Sang * probe()/remove() methods. A driver may be bound to this device when we 90691ed5349SWolfram Sang * return from this function, or any later moment (e.g. maybe hotplugging will 90791ed5349SWolfram Sang * load the driver module). This call is not appropriate for use by mainboard 90891ed5349SWolfram Sang * initialization logic, which usually runs during an arch_initcall() long 90991ed5349SWolfram Sang * before any i2c_adapter could exist. 91091ed5349SWolfram Sang * 91191ed5349SWolfram Sang * This returns the new i2c client, which may be saved for later use with 9127159dbdaSHeiner Kallweit * i2c_unregister_device(); or an ERR_PTR to describe the error. 91391ed5349SWolfram Sang */ 914550113d4SWolfram Sang struct i2c_client * 9157159dbdaSHeiner Kallweit i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) 91691ed5349SWolfram Sang { 91791ed5349SWolfram Sang struct i2c_client *client; 91891ed5349SWolfram Sang int status; 91991ed5349SWolfram Sang 92091ed5349SWolfram Sang client = kzalloc(sizeof *client, GFP_KERNEL); 92191ed5349SWolfram Sang if (!client) 9227159dbdaSHeiner Kallweit return ERR_PTR(-ENOMEM); 92391ed5349SWolfram Sang 92491ed5349SWolfram Sang client->adapter = adap; 92591ed5349SWolfram Sang 92691ed5349SWolfram Sang client->dev.platform_data = info->platform_data; 92791ed5349SWolfram Sang client->flags = info->flags; 92891ed5349SWolfram Sang client->addr = info->addr; 92991ed5349SWolfram Sang 93093b6604cSJim Broadus client->init_irq = info->irq; 93193b6604cSJim Broadus if (!client->init_irq) 93293b6604cSJim Broadus client->init_irq = i2c_dev_irq_from_resources(info->resources, 93391ed5349SWolfram Sang info->num_resources); 93491ed5349SWolfram Sang 93591ed5349SWolfram Sang strlcpy(client->name, info->type, sizeof(client->name)); 93691ed5349SWolfram Sang 93791ed5349SWolfram Sang status = i2c_check_addr_validity(client->addr, client->flags); 93891ed5349SWolfram Sang if (status) { 93991ed5349SWolfram Sang dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", 94091ed5349SWolfram Sang client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); 94191ed5349SWolfram Sang goto out_err_silent; 94291ed5349SWolfram Sang } 94391ed5349SWolfram Sang 94491ed5349SWolfram Sang /* Check for address business */ 94591ed5349SWolfram Sang status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); 94691ed5349SWolfram Sang if (status) 94791ed5349SWolfram Sang goto out_err; 94891ed5349SWolfram Sang 94991ed5349SWolfram Sang client->dev.parent = &client->adapter->dev; 95091ed5349SWolfram Sang client->dev.bus = &i2c_bus_type; 95191ed5349SWolfram Sang client->dev.type = &i2c_client_type; 95204782265SBoris Brezillon client->dev.of_node = of_node_get(info->of_node); 95391ed5349SWolfram Sang client->dev.fwnode = info->fwnode; 95491ed5349SWolfram Sang 955728fe6ceSHans de Goede i2c_dev_set_name(adap, client, info); 95691ed5349SWolfram Sang 957714638e0SHeikki Krogerus if (info->swnode) { 958714638e0SHeikki Krogerus status = device_add_software_node(&client->dev, info->swnode); 95991ed5349SWolfram Sang if (status) { 96091ed5349SWolfram Sang dev_err(&adap->dev, 961714638e0SHeikki Krogerus "Failed to add software node to client %s: %d\n", 96291ed5349SWolfram Sang client->name, status); 96304782265SBoris Brezillon goto out_err_put_of_node; 96491ed5349SWolfram Sang } 96591ed5349SWolfram Sang } 96691ed5349SWolfram Sang 96791ed5349SWolfram Sang status = device_register(&client->dev); 96891ed5349SWolfram Sang if (status) 969714638e0SHeikki Krogerus goto out_remove_swnode; 97091ed5349SWolfram Sang 97191ed5349SWolfram Sang dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", 97291ed5349SWolfram Sang client->name, dev_name(&client->dev)); 97391ed5349SWolfram Sang 97491ed5349SWolfram Sang return client; 97591ed5349SWolfram Sang 976714638e0SHeikki Krogerus out_remove_swnode: 977714638e0SHeikki Krogerus device_remove_software_node(&client->dev); 97804782265SBoris Brezillon out_err_put_of_node: 97904782265SBoris Brezillon of_node_put(info->of_node); 98091ed5349SWolfram Sang out_err: 98191ed5349SWolfram Sang dev_err(&adap->dev, 98291ed5349SWolfram Sang "Failed to register i2c client %s at 0x%02x (%d)\n", 98391ed5349SWolfram Sang client->name, client->addr, status); 98491ed5349SWolfram Sang out_err_silent: 98591ed5349SWolfram Sang kfree(client); 9867159dbdaSHeiner Kallweit return ERR_PTR(status); 9877159dbdaSHeiner Kallweit } 9887159dbdaSHeiner Kallweit EXPORT_SYMBOL_GPL(i2c_new_client_device); 9897159dbdaSHeiner Kallweit 9907159dbdaSHeiner Kallweit /** 99187e07437SWolfram Sang * i2c_unregister_device - reverse effect of i2c_new_*_device() 99287e07437SWolfram Sang * @client: value returned from i2c_new_*_device() 99391ed5349SWolfram Sang * Context: can sleep 99491ed5349SWolfram Sang */ 99591ed5349SWolfram Sang void i2c_unregister_device(struct i2c_client *client) 99691ed5349SWolfram Sang { 997689f5358SWolfram Sang if (IS_ERR_OR_NULL(client)) 9987b43dd19SAndy Shevchenko return; 999e0638fa4SLixin Wang 1000e0638fa4SLixin Wang if (client->dev.of_node) { 100191ed5349SWolfram Sang of_node_clear_flag(client->dev.of_node, OF_POPULATED); 1002e0638fa4SLixin Wang of_node_put(client->dev.of_node); 1003e0638fa4SLixin Wang } 1004e0638fa4SLixin Wang 100591ed5349SWolfram Sang if (ACPI_COMPANION(&client->dev)) 100691ed5349SWolfram Sang acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev)); 1007714638e0SHeikki Krogerus device_remove_software_node(&client->dev); 100891ed5349SWolfram Sang device_unregister(&client->dev); 100991ed5349SWolfram Sang } 101091ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_unregister_device); 101191ed5349SWolfram Sang 101291ed5349SWolfram Sang 101391ed5349SWolfram Sang static const struct i2c_device_id dummy_id[] = { 101491ed5349SWolfram Sang { "dummy", 0 }, 101591ed5349SWolfram Sang { }, 101691ed5349SWolfram Sang }; 101791ed5349SWolfram Sang 101891ed5349SWolfram Sang static int dummy_probe(struct i2c_client *client, 101991ed5349SWolfram Sang const struct i2c_device_id *id) 102091ed5349SWolfram Sang { 102191ed5349SWolfram Sang return 0; 102291ed5349SWolfram Sang } 102391ed5349SWolfram Sang 102491ed5349SWolfram Sang static int dummy_remove(struct i2c_client *client) 102591ed5349SWolfram Sang { 102691ed5349SWolfram Sang return 0; 102791ed5349SWolfram Sang } 102891ed5349SWolfram Sang 102991ed5349SWolfram Sang static struct i2c_driver dummy_driver = { 103091ed5349SWolfram Sang .driver.name = "dummy", 103191ed5349SWolfram Sang .probe = dummy_probe, 103291ed5349SWolfram Sang .remove = dummy_remove, 103391ed5349SWolfram Sang .id_table = dummy_id, 103491ed5349SWolfram Sang }; 103591ed5349SWolfram Sang 103691ed5349SWolfram Sang /** 10377159dbdaSHeiner Kallweit * i2c_new_dummy_device - return a new i2c device bound to a dummy driver 103891ed5349SWolfram Sang * @adapter: the adapter managing the device 103991ed5349SWolfram Sang * @address: seven bit address to be used 104091ed5349SWolfram Sang * Context: can sleep 104191ed5349SWolfram Sang * 104291ed5349SWolfram Sang * This returns an I2C client bound to the "dummy" driver, intended for use 104391ed5349SWolfram Sang * with devices that consume multiple addresses. Examples of such chips 104491ed5349SWolfram Sang * include various EEPROMS (like 24c04 and 24c08 models). 104591ed5349SWolfram Sang * 104691ed5349SWolfram Sang * These dummy devices have two main uses. First, most I2C and SMBus calls 104791ed5349SWolfram Sang * except i2c_transfer() need a client handle; the dummy will be that handle. 104891ed5349SWolfram Sang * And second, this prevents the specified address from being bound to a 104991ed5349SWolfram Sang * different driver. 105091ed5349SWolfram Sang * 105191ed5349SWolfram Sang * This returns the new i2c client, which should be saved for later use with 10527159dbdaSHeiner Kallweit * i2c_unregister_device(); or an ERR_PTR to describe the error. 105391ed5349SWolfram Sang */ 1054550113d4SWolfram Sang struct i2c_client *i2c_new_dummy_device(struct i2c_adapter *adapter, u16 address) 105591ed5349SWolfram Sang { 105691ed5349SWolfram Sang struct i2c_board_info info = { 105791ed5349SWolfram Sang I2C_BOARD_INFO("dummy", address), 105891ed5349SWolfram Sang }; 105991ed5349SWolfram Sang 10607159dbdaSHeiner Kallweit return i2c_new_client_device(adapter, &info); 10617159dbdaSHeiner Kallweit } 10627159dbdaSHeiner Kallweit EXPORT_SYMBOL_GPL(i2c_new_dummy_device); 10637159dbdaSHeiner Kallweit 1064bb7f086bSYicong Yang static void devm_i2c_release_dummy(void *client) 1065b8f5fe3bSHeiner Kallweit { 1066bb7f086bSYicong Yang i2c_unregister_device(client); 1067b8f5fe3bSHeiner Kallweit } 1068b8f5fe3bSHeiner Kallweit 1069b8f5fe3bSHeiner Kallweit /** 1070b8f5fe3bSHeiner Kallweit * devm_i2c_new_dummy_device - return a new i2c device bound to a dummy driver 1071b8f5fe3bSHeiner Kallweit * @dev: device the managed resource is bound to 1072b8f5fe3bSHeiner Kallweit * @adapter: the adapter managing the device 1073b8f5fe3bSHeiner Kallweit * @address: seven bit address to be used 1074b8f5fe3bSHeiner Kallweit * Context: can sleep 1075b8f5fe3bSHeiner Kallweit * 1076b8f5fe3bSHeiner Kallweit * This is the device-managed version of @i2c_new_dummy_device. It returns the 1077b8f5fe3bSHeiner Kallweit * new i2c client or an ERR_PTR in case of an error. 1078b8f5fe3bSHeiner Kallweit */ 1079b8f5fe3bSHeiner Kallweit struct i2c_client *devm_i2c_new_dummy_device(struct device *dev, 1080b8f5fe3bSHeiner Kallweit struct i2c_adapter *adapter, 1081b8f5fe3bSHeiner Kallweit u16 address) 1082b8f5fe3bSHeiner Kallweit { 1083b8f5fe3bSHeiner Kallweit struct i2c_client *client; 1084bb7f086bSYicong Yang int ret; 1085b8f5fe3bSHeiner Kallweit 1086b8f5fe3bSHeiner Kallweit client = i2c_new_dummy_device(adapter, address); 1087bb7f086bSYicong Yang if (IS_ERR(client)) 1088bb7f086bSYicong Yang return client; 1089bb7f086bSYicong Yang 1090bb7f086bSYicong Yang ret = devm_add_action_or_reset(dev, devm_i2c_release_dummy, client); 1091bb7f086bSYicong Yang if (ret) 1092bb7f086bSYicong Yang return ERR_PTR(ret); 1093b8f5fe3bSHeiner Kallweit 1094b8f5fe3bSHeiner Kallweit return client; 1095b8f5fe3bSHeiner Kallweit } 1096b8f5fe3bSHeiner Kallweit EXPORT_SYMBOL_GPL(devm_i2c_new_dummy_device); 1097b8f5fe3bSHeiner Kallweit 109891ed5349SWolfram Sang /** 1099af80559bSWolfram Sang * i2c_new_ancillary_device - Helper to get the instantiated secondary address 110091ed5349SWolfram Sang * and create the associated device 110191ed5349SWolfram Sang * @client: Handle to the primary client 110291ed5349SWolfram Sang * @name: Handle to specify which secondary address to get 110391ed5349SWolfram Sang * @default_addr: Used as a fallback if no secondary address was specified 110491ed5349SWolfram Sang * Context: can sleep 110591ed5349SWolfram Sang * 110691ed5349SWolfram Sang * I2C clients can be composed of multiple I2C slaves bound together in a single 110791ed5349SWolfram Sang * component. The I2C client driver then binds to the master I2C slave and needs 110891ed5349SWolfram Sang * to create I2C dummy clients to communicate with all the other slaves. 110991ed5349SWolfram Sang * 111091ed5349SWolfram Sang * This function creates and returns an I2C dummy client whose I2C address is 111191ed5349SWolfram Sang * retrieved from the platform firmware based on the given slave name. If no 111291ed5349SWolfram Sang * address is specified by the firmware default_addr is used. 111391ed5349SWolfram Sang * 111491ed5349SWolfram Sang * On DT-based platforms the address is retrieved from the "reg" property entry 111591ed5349SWolfram Sang * cell whose "reg-names" value matches the slave name. 111691ed5349SWolfram Sang * 111791ed5349SWolfram Sang * This returns the new i2c client, which should be saved for later use with 1118af80559bSWolfram Sang * i2c_unregister_device(); or an ERR_PTR to describe the error. 111991ed5349SWolfram Sang */ 1120af80559bSWolfram Sang struct i2c_client *i2c_new_ancillary_device(struct i2c_client *client, 112191ed5349SWolfram Sang const char *name, 112291ed5349SWolfram Sang u16 default_addr) 112391ed5349SWolfram Sang { 112491ed5349SWolfram Sang struct device_node *np = client->dev.of_node; 112591ed5349SWolfram Sang u32 addr = default_addr; 112691ed5349SWolfram Sang int i; 112791ed5349SWolfram Sang 112891ed5349SWolfram Sang if (np) { 112991ed5349SWolfram Sang i = of_property_match_string(np, "reg-names", name); 113091ed5349SWolfram Sang if (i >= 0) 113191ed5349SWolfram Sang of_property_read_u32_index(np, "reg", i, &addr); 113291ed5349SWolfram Sang } 113391ed5349SWolfram Sang 113491ed5349SWolfram Sang dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); 1135af80559bSWolfram Sang return i2c_new_dummy_device(client->adapter, addr); 113691ed5349SWolfram Sang } 1137af80559bSWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_ancillary_device); 113891ed5349SWolfram Sang 113991ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 114091ed5349SWolfram Sang 114191ed5349SWolfram Sang /* I2C bus adapters -- one roots each I2C or SMBUS segment */ 114291ed5349SWolfram Sang 114391ed5349SWolfram Sang static void i2c_adapter_dev_release(struct device *dev) 114491ed5349SWolfram Sang { 114591ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 114691ed5349SWolfram Sang complete(&adap->dev_released); 114791ed5349SWolfram Sang } 114891ed5349SWolfram Sang 114991ed5349SWolfram Sang unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) 115091ed5349SWolfram Sang { 115191ed5349SWolfram Sang unsigned int depth = 0; 115291ed5349SWolfram Sang 115391ed5349SWolfram Sang while ((adapter = i2c_parent_is_i2c_adapter(adapter))) 115491ed5349SWolfram Sang depth++; 115591ed5349SWolfram Sang 115691ed5349SWolfram Sang WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES, 115791ed5349SWolfram Sang "adapter depth exceeds lockdep subclass limit\n"); 115891ed5349SWolfram Sang 115991ed5349SWolfram Sang return depth; 116091ed5349SWolfram Sang } 116191ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_adapter_depth); 116291ed5349SWolfram Sang 116391ed5349SWolfram Sang /* 116491ed5349SWolfram Sang * Let users instantiate I2C devices through sysfs. This can be used when 116591ed5349SWolfram Sang * platform initialization code doesn't contain the proper data for 116691ed5349SWolfram Sang * whatever reason. Also useful for drivers that do device detection and 116791ed5349SWolfram Sang * detection fails, either because the device uses an unexpected address, 116891ed5349SWolfram Sang * or this is a compatible device with different ID register values. 116991ed5349SWolfram Sang * 117091ed5349SWolfram Sang * Parameter checking may look overzealous, but we really don't want 117191ed5349SWolfram Sang * the user to provide incorrect parameters. 117291ed5349SWolfram Sang */ 117391ed5349SWolfram Sang static ssize_t 117454a19fd4SGeert Uytterhoeven new_device_store(struct device *dev, struct device_attribute *attr, 117591ed5349SWolfram Sang const char *buf, size_t count) 117691ed5349SWolfram Sang { 117791ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 117891ed5349SWolfram Sang struct i2c_board_info info; 117991ed5349SWolfram Sang struct i2c_client *client; 118091ed5349SWolfram Sang char *blank, end; 118191ed5349SWolfram Sang int res; 118291ed5349SWolfram Sang 118391ed5349SWolfram Sang memset(&info, 0, sizeof(struct i2c_board_info)); 118491ed5349SWolfram Sang 118591ed5349SWolfram Sang blank = strchr(buf, ' '); 118691ed5349SWolfram Sang if (!blank) { 118791ed5349SWolfram Sang dev_err(dev, "%s: Missing parameters\n", "new_device"); 118891ed5349SWolfram Sang return -EINVAL; 118991ed5349SWolfram Sang } 119091ed5349SWolfram Sang if (blank - buf > I2C_NAME_SIZE - 1) { 119191ed5349SWolfram Sang dev_err(dev, "%s: Invalid device name\n", "new_device"); 119291ed5349SWolfram Sang return -EINVAL; 119391ed5349SWolfram Sang } 119491ed5349SWolfram Sang memcpy(info.type, buf, blank - buf); 119591ed5349SWolfram Sang 119691ed5349SWolfram Sang /* Parse remaining parameters, reject extra parameters */ 119791ed5349SWolfram Sang res = sscanf(++blank, "%hi%c", &info.addr, &end); 119891ed5349SWolfram Sang if (res < 1) { 119991ed5349SWolfram Sang dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); 120091ed5349SWolfram Sang return -EINVAL; 120191ed5349SWolfram Sang } 120291ed5349SWolfram Sang if (res > 1 && end != '\n') { 120391ed5349SWolfram Sang dev_err(dev, "%s: Extra parameters\n", "new_device"); 120491ed5349SWolfram Sang return -EINVAL; 120591ed5349SWolfram Sang } 120691ed5349SWolfram Sang 120791ed5349SWolfram Sang if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { 120891ed5349SWolfram Sang info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; 120991ed5349SWolfram Sang info.flags |= I2C_CLIENT_TEN; 121091ed5349SWolfram Sang } 121191ed5349SWolfram Sang 121291ed5349SWolfram Sang if (info.addr & I2C_ADDR_OFFSET_SLAVE) { 121391ed5349SWolfram Sang info.addr &= ~I2C_ADDR_OFFSET_SLAVE; 121491ed5349SWolfram Sang info.flags |= I2C_CLIENT_SLAVE; 121591ed5349SWolfram Sang } 121691ed5349SWolfram Sang 12177159dbdaSHeiner Kallweit client = i2c_new_client_device(adap, &info); 12187159dbdaSHeiner Kallweit if (IS_ERR(client)) 12197159dbdaSHeiner Kallweit return PTR_ERR(client); 122091ed5349SWolfram Sang 122191ed5349SWolfram Sang /* Keep track of the added device */ 122291ed5349SWolfram Sang mutex_lock(&adap->userspace_clients_lock); 122391ed5349SWolfram Sang list_add_tail(&client->detected, &adap->userspace_clients); 122491ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 122591ed5349SWolfram Sang dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", 122691ed5349SWolfram Sang info.type, info.addr); 122791ed5349SWolfram Sang 122891ed5349SWolfram Sang return count; 122991ed5349SWolfram Sang } 123054a19fd4SGeert Uytterhoeven static DEVICE_ATTR_WO(new_device); 123191ed5349SWolfram Sang 123291ed5349SWolfram Sang /* 123391ed5349SWolfram Sang * And of course let the users delete the devices they instantiated, if 123491ed5349SWolfram Sang * they got it wrong. This interface can only be used to delete devices 123591ed5349SWolfram Sang * instantiated by i2c_sysfs_new_device above. This guarantees that we 123691ed5349SWolfram Sang * don't delete devices to which some kernel code still has references. 123791ed5349SWolfram Sang * 123891ed5349SWolfram Sang * Parameter checking may look overzealous, but we really don't want 123991ed5349SWolfram Sang * the user to delete the wrong device. 124091ed5349SWolfram Sang */ 124191ed5349SWolfram Sang static ssize_t 124254a19fd4SGeert Uytterhoeven delete_device_store(struct device *dev, struct device_attribute *attr, 124391ed5349SWolfram Sang const char *buf, size_t count) 124491ed5349SWolfram Sang { 124591ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 124691ed5349SWolfram Sang struct i2c_client *client, *next; 124791ed5349SWolfram Sang unsigned short addr; 124891ed5349SWolfram Sang char end; 124991ed5349SWolfram Sang int res; 125091ed5349SWolfram Sang 125191ed5349SWolfram Sang /* Parse parameters, reject extra parameters */ 125291ed5349SWolfram Sang res = sscanf(buf, "%hi%c", &addr, &end); 125391ed5349SWolfram Sang if (res < 1) { 125491ed5349SWolfram Sang dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); 125591ed5349SWolfram Sang return -EINVAL; 125691ed5349SWolfram Sang } 125791ed5349SWolfram Sang if (res > 1 && end != '\n') { 125891ed5349SWolfram Sang dev_err(dev, "%s: Extra parameters\n", "delete_device"); 125991ed5349SWolfram Sang return -EINVAL; 126091ed5349SWolfram Sang } 126191ed5349SWolfram Sang 126291ed5349SWolfram Sang /* Make sure the device was added through sysfs */ 126391ed5349SWolfram Sang res = -ENOENT; 126491ed5349SWolfram Sang mutex_lock_nested(&adap->userspace_clients_lock, 126591ed5349SWolfram Sang i2c_adapter_depth(adap)); 126691ed5349SWolfram Sang list_for_each_entry_safe(client, next, &adap->userspace_clients, 126791ed5349SWolfram Sang detected) { 126891ed5349SWolfram Sang if (i2c_encode_flags_to_addr(client) == addr) { 126991ed5349SWolfram Sang dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", 127091ed5349SWolfram Sang "delete_device", client->name, client->addr); 127191ed5349SWolfram Sang 127291ed5349SWolfram Sang list_del(&client->detected); 127391ed5349SWolfram Sang i2c_unregister_device(client); 127491ed5349SWolfram Sang res = count; 127591ed5349SWolfram Sang break; 127691ed5349SWolfram Sang } 127791ed5349SWolfram Sang } 127891ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 127991ed5349SWolfram Sang 128091ed5349SWolfram Sang if (res < 0) 128191ed5349SWolfram Sang dev_err(dev, "%s: Can't find device in list\n", 128291ed5349SWolfram Sang "delete_device"); 128391ed5349SWolfram Sang return res; 128491ed5349SWolfram Sang } 128591ed5349SWolfram Sang static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, 128654a19fd4SGeert Uytterhoeven delete_device_store); 128791ed5349SWolfram Sang 128891ed5349SWolfram Sang static struct attribute *i2c_adapter_attrs[] = { 128991ed5349SWolfram Sang &dev_attr_name.attr, 129091ed5349SWolfram Sang &dev_attr_new_device.attr, 129191ed5349SWolfram Sang &dev_attr_delete_device.attr, 129291ed5349SWolfram Sang NULL 129391ed5349SWolfram Sang }; 129491ed5349SWolfram Sang ATTRIBUTE_GROUPS(i2c_adapter); 129591ed5349SWolfram Sang 129691ed5349SWolfram Sang struct device_type i2c_adapter_type = { 129791ed5349SWolfram Sang .groups = i2c_adapter_groups, 129891ed5349SWolfram Sang .release = i2c_adapter_dev_release, 129991ed5349SWolfram Sang }; 130091ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_adapter_type); 130191ed5349SWolfram Sang 130291ed5349SWolfram Sang /** 130391ed5349SWolfram Sang * i2c_verify_adapter - return parameter as i2c_adapter or NULL 130491ed5349SWolfram Sang * @dev: device, probably from some driver model iterator 130591ed5349SWolfram Sang * 130691ed5349SWolfram Sang * When traversing the driver model tree, perhaps using driver model 130791ed5349SWolfram Sang * iterators like @device_for_each_child(), you can't assume very much 130891ed5349SWolfram Sang * about the nodes you find. Use this function to avoid oopses caused 130991ed5349SWolfram Sang * by wrongly treating some non-I2C device as an i2c_adapter. 131091ed5349SWolfram Sang */ 131191ed5349SWolfram Sang struct i2c_adapter *i2c_verify_adapter(struct device *dev) 131291ed5349SWolfram Sang { 131391ed5349SWolfram Sang return (dev->type == &i2c_adapter_type) 131491ed5349SWolfram Sang ? to_i2c_adapter(dev) 131591ed5349SWolfram Sang : NULL; 131691ed5349SWolfram Sang } 131791ed5349SWolfram Sang EXPORT_SYMBOL(i2c_verify_adapter); 131891ed5349SWolfram Sang 131991ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 132091ed5349SWolfram Sang static struct class_compat *i2c_adapter_compat_class; 132191ed5349SWolfram Sang #endif 132291ed5349SWolfram Sang 132391ed5349SWolfram Sang static void i2c_scan_static_board_info(struct i2c_adapter *adapter) 132491ed5349SWolfram Sang { 132591ed5349SWolfram Sang struct i2c_devinfo *devinfo; 132691ed5349SWolfram Sang 132791ed5349SWolfram Sang down_read(&__i2c_board_lock); 132891ed5349SWolfram Sang list_for_each_entry(devinfo, &__i2c_board_list, list) { 132987e07437SWolfram Sang if (devinfo->busnum == adapter->nr && 133087e07437SWolfram Sang IS_ERR(i2c_new_client_device(adapter, &devinfo->board_info))) 133191ed5349SWolfram Sang dev_err(&adapter->dev, 133291ed5349SWolfram Sang "Can't create device at 0x%02x\n", 133391ed5349SWolfram Sang devinfo->board_info.addr); 133491ed5349SWolfram Sang } 133591ed5349SWolfram Sang up_read(&__i2c_board_lock); 133691ed5349SWolfram Sang } 133791ed5349SWolfram Sang 133891ed5349SWolfram Sang static int i2c_do_add_adapter(struct i2c_driver *driver, 133991ed5349SWolfram Sang struct i2c_adapter *adap) 134091ed5349SWolfram Sang { 134191ed5349SWolfram Sang /* Detect supported devices on that bus, and instantiate them */ 134291ed5349SWolfram Sang i2c_detect(adap, driver); 134391ed5349SWolfram Sang 134491ed5349SWolfram Sang return 0; 134591ed5349SWolfram Sang } 134691ed5349SWolfram Sang 134791ed5349SWolfram Sang static int __process_new_adapter(struct device_driver *d, void *data) 134891ed5349SWolfram Sang { 134991ed5349SWolfram Sang return i2c_do_add_adapter(to_i2c_driver(d), data); 135091ed5349SWolfram Sang } 135191ed5349SWolfram Sang 135291ed5349SWolfram Sang static const struct i2c_lock_operations i2c_adapter_lock_ops = { 135391ed5349SWolfram Sang .lock_bus = i2c_adapter_lock_bus, 135491ed5349SWolfram Sang .trylock_bus = i2c_adapter_trylock_bus, 135591ed5349SWolfram Sang .unlock_bus = i2c_adapter_unlock_bus, 135691ed5349SWolfram Sang }; 135791ed5349SWolfram Sang 135891ed5349SWolfram Sang static void i2c_host_notify_irq_teardown(struct i2c_adapter *adap) 135991ed5349SWolfram Sang { 136091ed5349SWolfram Sang struct irq_domain *domain = adap->host_notify_domain; 136191ed5349SWolfram Sang irq_hw_number_t hwirq; 136291ed5349SWolfram Sang 136391ed5349SWolfram Sang if (!domain) 136491ed5349SWolfram Sang return; 136591ed5349SWolfram Sang 136691ed5349SWolfram Sang for (hwirq = 0 ; hwirq < I2C_ADDR_7BITS_COUNT ; hwirq++) 136791ed5349SWolfram Sang irq_dispose_mapping(irq_find_mapping(domain, hwirq)); 136891ed5349SWolfram Sang 136991ed5349SWolfram Sang irq_domain_remove(domain); 137091ed5349SWolfram Sang adap->host_notify_domain = NULL; 137191ed5349SWolfram Sang } 137291ed5349SWolfram Sang 137391ed5349SWolfram Sang static int i2c_host_notify_irq_map(struct irq_domain *h, 137491ed5349SWolfram Sang unsigned int virq, 137591ed5349SWolfram Sang irq_hw_number_t hw_irq_num) 137691ed5349SWolfram Sang { 137791ed5349SWolfram Sang irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); 137891ed5349SWolfram Sang 137991ed5349SWolfram Sang return 0; 138091ed5349SWolfram Sang } 138191ed5349SWolfram Sang 138291ed5349SWolfram Sang static const struct irq_domain_ops i2c_host_notify_irq_ops = { 138391ed5349SWolfram Sang .map = i2c_host_notify_irq_map, 138491ed5349SWolfram Sang }; 138591ed5349SWolfram Sang 138691ed5349SWolfram Sang static int i2c_setup_host_notify_irq_domain(struct i2c_adapter *adap) 138791ed5349SWolfram Sang { 138891ed5349SWolfram Sang struct irq_domain *domain; 138991ed5349SWolfram Sang 139091ed5349SWolfram Sang if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_HOST_NOTIFY)) 139191ed5349SWolfram Sang return 0; 139291ed5349SWolfram Sang 13938682dc12SWolfram Sang domain = irq_domain_create_linear(adap->dev.parent->fwnode, 139491ed5349SWolfram Sang I2C_ADDR_7BITS_COUNT, 139591ed5349SWolfram Sang &i2c_host_notify_irq_ops, adap); 139691ed5349SWolfram Sang if (!domain) 139791ed5349SWolfram Sang return -ENOMEM; 139891ed5349SWolfram Sang 139991ed5349SWolfram Sang adap->host_notify_domain = domain; 140091ed5349SWolfram Sang 140191ed5349SWolfram Sang return 0; 140291ed5349SWolfram Sang } 140391ed5349SWolfram Sang 140491ed5349SWolfram Sang /** 140591ed5349SWolfram Sang * i2c_handle_smbus_host_notify - Forward a Host Notify event to the correct 140691ed5349SWolfram Sang * I2C client. 140791ed5349SWolfram Sang * @adap: the adapter 140891ed5349SWolfram Sang * @addr: the I2C address of the notifying device 140991ed5349SWolfram Sang * Context: can't sleep 141091ed5349SWolfram Sang * 141191ed5349SWolfram Sang * Helper function to be called from an I2C bus driver's interrupt 141291ed5349SWolfram Sang * handler. It will schedule the Host Notify IRQ. 141391ed5349SWolfram Sang */ 141491ed5349SWolfram Sang int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr) 141591ed5349SWolfram Sang { 141691ed5349SWolfram Sang int irq; 141791ed5349SWolfram Sang 141891ed5349SWolfram Sang if (!adap) 141991ed5349SWolfram Sang return -EINVAL; 142091ed5349SWolfram Sang 142191ed5349SWolfram Sang irq = irq_find_mapping(adap->host_notify_domain, addr); 142291ed5349SWolfram Sang if (irq <= 0) 142391ed5349SWolfram Sang return -ENXIO; 142491ed5349SWolfram Sang 142591ed5349SWolfram Sang generic_handle_irq(irq); 142691ed5349SWolfram Sang 142791ed5349SWolfram Sang return 0; 142891ed5349SWolfram Sang } 142991ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify); 143091ed5349SWolfram Sang 143191ed5349SWolfram Sang static int i2c_register_adapter(struct i2c_adapter *adap) 143291ed5349SWolfram Sang { 143391ed5349SWolfram Sang int res = -EINVAL; 143491ed5349SWolfram Sang 143591ed5349SWolfram Sang /* Can't register until after driver model init */ 143691ed5349SWolfram Sang if (WARN_ON(!is_registered)) { 143791ed5349SWolfram Sang res = -EAGAIN; 143891ed5349SWolfram Sang goto out_list; 143991ed5349SWolfram Sang } 144091ed5349SWolfram Sang 144191ed5349SWolfram Sang /* Sanity checks */ 144291ed5349SWolfram Sang if (WARN(!adap->name[0], "i2c adapter has no name")) 144391ed5349SWolfram Sang goto out_list; 144491ed5349SWolfram Sang 144591ed5349SWolfram Sang if (!adap->algo) { 144691ed5349SWolfram Sang pr_err("adapter '%s': no algo supplied!\n", adap->name); 144791ed5349SWolfram Sang goto out_list; 144891ed5349SWolfram Sang } 144991ed5349SWolfram Sang 145091ed5349SWolfram Sang if (!adap->lock_ops) 145191ed5349SWolfram Sang adap->lock_ops = &i2c_adapter_lock_ops; 145291ed5349SWolfram Sang 14539ac6cb5fSWolfram Sang adap->locked_flags = 0; 145491ed5349SWolfram Sang rt_mutex_init(&adap->bus_lock); 145591ed5349SWolfram Sang rt_mutex_init(&adap->mux_lock); 145691ed5349SWolfram Sang mutex_init(&adap->userspace_clients_lock); 145791ed5349SWolfram Sang INIT_LIST_HEAD(&adap->userspace_clients); 145891ed5349SWolfram Sang 145991ed5349SWolfram Sang /* Set default timeout to 1 second if not already set */ 146091ed5349SWolfram Sang if (adap->timeout == 0) 146191ed5349SWolfram Sang adap->timeout = HZ; 146291ed5349SWolfram Sang 146391ed5349SWolfram Sang /* register soft irqs for Host Notify */ 146491ed5349SWolfram Sang res = i2c_setup_host_notify_irq_domain(adap); 146591ed5349SWolfram Sang if (res) { 146691ed5349SWolfram Sang pr_err("adapter '%s': can't create Host Notify IRQs (%d)\n", 146791ed5349SWolfram Sang adap->name, res); 146891ed5349SWolfram Sang goto out_list; 146991ed5349SWolfram Sang } 147091ed5349SWolfram Sang 147191ed5349SWolfram Sang dev_set_name(&adap->dev, "i2c-%d", adap->nr); 147291ed5349SWolfram Sang adap->dev.bus = &i2c_bus_type; 147391ed5349SWolfram Sang adap->dev.type = &i2c_adapter_type; 147491ed5349SWolfram Sang res = device_register(&adap->dev); 147591ed5349SWolfram Sang if (res) { 147691ed5349SWolfram Sang pr_err("adapter '%s': can't register device (%d)\n", adap->name, res); 147791ed5349SWolfram Sang goto out_list; 147891ed5349SWolfram Sang } 147991ed5349SWolfram Sang 1480f8756c67SPhil Reid res = of_i2c_setup_smbus_alert(adap); 1481f8756c67SPhil Reid if (res) 1482f8756c67SPhil Reid goto out_reg; 1483f8756c67SPhil Reid 148491ed5349SWolfram Sang pm_runtime_no_callbacks(&adap->dev); 148591ed5349SWolfram Sang pm_suspend_ignore_children(&adap->dev, true); 148691ed5349SWolfram Sang pm_runtime_enable(&adap->dev); 148791ed5349SWolfram Sang 148823a698feSCodrin Ciubotariu res = i2c_init_recovery(adap); 148923a698feSCodrin Ciubotariu if (res == -EPROBE_DEFER) 149023a698feSCodrin Ciubotariu goto out_reg; 149123a698feSCodrin Ciubotariu 149223a698feSCodrin Ciubotariu dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); 149323a698feSCodrin Ciubotariu 149491ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 149591ed5349SWolfram Sang res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, 149691ed5349SWolfram Sang adap->dev.parent); 149791ed5349SWolfram Sang if (res) 149891ed5349SWolfram Sang dev_warn(&adap->dev, 149991ed5349SWolfram Sang "Failed to create compatibility class link\n"); 150091ed5349SWolfram Sang #endif 150191ed5349SWolfram Sang 150291ed5349SWolfram Sang /* create pre-declared device nodes */ 150391ed5349SWolfram Sang of_i2c_register_devices(adap); 150491ed5349SWolfram Sang i2c_acpi_install_space_handler(adap); 150521653a41SHans de Goede i2c_acpi_register_devices(adap); 150691ed5349SWolfram Sang 150791ed5349SWolfram Sang if (adap->nr < __i2c_first_dynamic_bus_num) 150891ed5349SWolfram Sang i2c_scan_static_board_info(adap); 150991ed5349SWolfram Sang 151091ed5349SWolfram Sang /* Notify drivers */ 151191ed5349SWolfram Sang mutex_lock(&core_lock); 151291ed5349SWolfram Sang bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); 151391ed5349SWolfram Sang mutex_unlock(&core_lock); 151491ed5349SWolfram Sang 151591ed5349SWolfram Sang return 0; 151691ed5349SWolfram Sang 1517f8756c67SPhil Reid out_reg: 1518f8756c67SPhil Reid init_completion(&adap->dev_released); 1519f8756c67SPhil Reid device_unregister(&adap->dev); 1520f8756c67SPhil Reid wait_for_completion(&adap->dev_released); 152191ed5349SWolfram Sang out_list: 152291ed5349SWolfram Sang mutex_lock(&core_lock); 152391ed5349SWolfram Sang idr_remove(&i2c_adapter_idr, adap->nr); 152491ed5349SWolfram Sang mutex_unlock(&core_lock); 152591ed5349SWolfram Sang return res; 152691ed5349SWolfram Sang } 152791ed5349SWolfram Sang 152891ed5349SWolfram Sang /** 152991ed5349SWolfram Sang * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 153091ed5349SWolfram Sang * @adap: the adapter to register (with adap->nr initialized) 153191ed5349SWolfram Sang * Context: can sleep 153291ed5349SWolfram Sang * 153391ed5349SWolfram Sang * See i2c_add_numbered_adapter() for details. 153491ed5349SWolfram Sang */ 153591ed5349SWolfram Sang static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) 153691ed5349SWolfram Sang { 153791ed5349SWolfram Sang int id; 153891ed5349SWolfram Sang 153991ed5349SWolfram Sang mutex_lock(&core_lock); 154091ed5349SWolfram Sang id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); 154191ed5349SWolfram Sang mutex_unlock(&core_lock); 154291ed5349SWolfram Sang if (WARN(id < 0, "couldn't get idr")) 154391ed5349SWolfram Sang return id == -ENOSPC ? -EBUSY : id; 154491ed5349SWolfram Sang 154591ed5349SWolfram Sang return i2c_register_adapter(adap); 154691ed5349SWolfram Sang } 154791ed5349SWolfram Sang 154891ed5349SWolfram Sang /** 154991ed5349SWolfram Sang * i2c_add_adapter - declare i2c adapter, use dynamic bus number 155091ed5349SWolfram Sang * @adapter: the adapter to add 155191ed5349SWolfram Sang * Context: can sleep 155291ed5349SWolfram Sang * 155391ed5349SWolfram Sang * This routine is used to declare an I2C adapter when its bus number 155491ed5349SWolfram Sang * doesn't matter or when its bus number is specified by an dt alias. 155591ed5349SWolfram Sang * Examples of bases when the bus number doesn't matter: I2C adapters 155691ed5349SWolfram Sang * dynamically added by USB links or PCI plugin cards. 155791ed5349SWolfram Sang * 155891ed5349SWolfram Sang * When this returns zero, a new bus number was allocated and stored 155991ed5349SWolfram Sang * in adap->nr, and the specified adapter became available for clients. 156091ed5349SWolfram Sang * Otherwise, a negative errno value is returned. 156191ed5349SWolfram Sang */ 156291ed5349SWolfram Sang int i2c_add_adapter(struct i2c_adapter *adapter) 156391ed5349SWolfram Sang { 156491ed5349SWolfram Sang struct device *dev = &adapter->dev; 156591ed5349SWolfram Sang int id; 156691ed5349SWolfram Sang 156791ed5349SWolfram Sang if (dev->of_node) { 156891ed5349SWolfram Sang id = of_alias_get_id(dev->of_node, "i2c"); 156991ed5349SWolfram Sang if (id >= 0) { 157091ed5349SWolfram Sang adapter->nr = id; 157191ed5349SWolfram Sang return __i2c_add_numbered_adapter(adapter); 157291ed5349SWolfram Sang } 157391ed5349SWolfram Sang } 157491ed5349SWolfram Sang 157591ed5349SWolfram Sang mutex_lock(&core_lock); 157691ed5349SWolfram Sang id = idr_alloc(&i2c_adapter_idr, adapter, 157791ed5349SWolfram Sang __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); 157891ed5349SWolfram Sang mutex_unlock(&core_lock); 157991ed5349SWolfram Sang if (WARN(id < 0, "couldn't get idr")) 158091ed5349SWolfram Sang return id; 158191ed5349SWolfram Sang 158291ed5349SWolfram Sang adapter->nr = id; 158391ed5349SWolfram Sang 158491ed5349SWolfram Sang return i2c_register_adapter(adapter); 158591ed5349SWolfram Sang } 158691ed5349SWolfram Sang EXPORT_SYMBOL(i2c_add_adapter); 158791ed5349SWolfram Sang 158891ed5349SWolfram Sang /** 158991ed5349SWolfram Sang * i2c_add_numbered_adapter - declare i2c adapter, use static bus number 159091ed5349SWolfram Sang * @adap: the adapter to register (with adap->nr initialized) 159191ed5349SWolfram Sang * Context: can sleep 159291ed5349SWolfram Sang * 159391ed5349SWolfram Sang * This routine is used to declare an I2C adapter when its bus number 159491ed5349SWolfram Sang * matters. For example, use it for I2C adapters from system-on-chip CPUs, 159591ed5349SWolfram Sang * or otherwise built in to the system's mainboard, and where i2c_board_info 159691ed5349SWolfram Sang * is used to properly configure I2C devices. 159791ed5349SWolfram Sang * 159891ed5349SWolfram Sang * If the requested bus number is set to -1, then this function will behave 159991ed5349SWolfram Sang * identically to i2c_add_adapter, and will dynamically assign a bus number. 160091ed5349SWolfram Sang * 160191ed5349SWolfram Sang * If no devices have pre-been declared for this bus, then be sure to 160291ed5349SWolfram Sang * register the adapter before any dynamically allocated ones. Otherwise 160391ed5349SWolfram Sang * the required bus ID may not be available. 160491ed5349SWolfram Sang * 160591ed5349SWolfram Sang * When this returns zero, the specified adapter became available for 160691ed5349SWolfram Sang * clients using the bus number provided in adap->nr. Also, the table 160791ed5349SWolfram Sang * of I2C devices pre-declared using i2c_register_board_info() is scanned, 160891ed5349SWolfram Sang * and the appropriate driver model device nodes are created. Otherwise, a 160991ed5349SWolfram Sang * negative errno value is returned. 161091ed5349SWolfram Sang */ 161191ed5349SWolfram Sang int i2c_add_numbered_adapter(struct i2c_adapter *adap) 161291ed5349SWolfram Sang { 161391ed5349SWolfram Sang if (adap->nr == -1) /* -1 means dynamically assign bus id */ 161491ed5349SWolfram Sang return i2c_add_adapter(adap); 161591ed5349SWolfram Sang 161691ed5349SWolfram Sang return __i2c_add_numbered_adapter(adap); 161791ed5349SWolfram Sang } 161891ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); 161991ed5349SWolfram Sang 162091ed5349SWolfram Sang static void i2c_do_del_adapter(struct i2c_driver *driver, 162191ed5349SWolfram Sang struct i2c_adapter *adapter) 162291ed5349SWolfram Sang { 162391ed5349SWolfram Sang struct i2c_client *client, *_n; 162491ed5349SWolfram Sang 162591ed5349SWolfram Sang /* Remove the devices we created ourselves as the result of hardware 162691ed5349SWolfram Sang * probing (using a driver's detect method) */ 162791ed5349SWolfram Sang list_for_each_entry_safe(client, _n, &driver->clients, detected) { 162891ed5349SWolfram Sang if (client->adapter == adapter) { 162991ed5349SWolfram Sang dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", 163091ed5349SWolfram Sang client->name, client->addr); 163191ed5349SWolfram Sang list_del(&client->detected); 163291ed5349SWolfram Sang i2c_unregister_device(client); 163391ed5349SWolfram Sang } 163491ed5349SWolfram Sang } 163591ed5349SWolfram Sang } 163691ed5349SWolfram Sang 163791ed5349SWolfram Sang static int __unregister_client(struct device *dev, void *dummy) 163891ed5349SWolfram Sang { 163991ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 164091ed5349SWolfram Sang if (client && strcmp(client->name, "dummy")) 164191ed5349SWolfram Sang i2c_unregister_device(client); 164291ed5349SWolfram Sang return 0; 164391ed5349SWolfram Sang } 164491ed5349SWolfram Sang 164591ed5349SWolfram Sang static int __unregister_dummy(struct device *dev, void *dummy) 164691ed5349SWolfram Sang { 164791ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 164891ed5349SWolfram Sang i2c_unregister_device(client); 164991ed5349SWolfram Sang return 0; 165091ed5349SWolfram Sang } 165191ed5349SWolfram Sang 165291ed5349SWolfram Sang static int __process_removed_adapter(struct device_driver *d, void *data) 165391ed5349SWolfram Sang { 165491ed5349SWolfram Sang i2c_do_del_adapter(to_i2c_driver(d), data); 165591ed5349SWolfram Sang return 0; 165691ed5349SWolfram Sang } 165791ed5349SWolfram Sang 165891ed5349SWolfram Sang /** 165991ed5349SWolfram Sang * i2c_del_adapter - unregister I2C adapter 166091ed5349SWolfram Sang * @adap: the adapter being unregistered 166191ed5349SWolfram Sang * Context: can sleep 166291ed5349SWolfram Sang * 166391ed5349SWolfram Sang * This unregisters an I2C adapter which was previously registered 166491ed5349SWolfram Sang * by @i2c_add_adapter or @i2c_add_numbered_adapter. 166591ed5349SWolfram Sang */ 166691ed5349SWolfram Sang void i2c_del_adapter(struct i2c_adapter *adap) 166791ed5349SWolfram Sang { 166891ed5349SWolfram Sang struct i2c_adapter *found; 166991ed5349SWolfram Sang struct i2c_client *client, *next; 167091ed5349SWolfram Sang 167191ed5349SWolfram Sang /* First make sure that this adapter was ever added */ 167291ed5349SWolfram Sang mutex_lock(&core_lock); 167391ed5349SWolfram Sang found = idr_find(&i2c_adapter_idr, adap->nr); 167491ed5349SWolfram Sang mutex_unlock(&core_lock); 167591ed5349SWolfram Sang if (found != adap) { 167691ed5349SWolfram Sang pr_debug("attempting to delete unregistered adapter [%s]\n", adap->name); 167791ed5349SWolfram Sang return; 167891ed5349SWolfram Sang } 167991ed5349SWolfram Sang 168091ed5349SWolfram Sang i2c_acpi_remove_space_handler(adap); 168191ed5349SWolfram Sang /* Tell drivers about this removal */ 168291ed5349SWolfram Sang mutex_lock(&core_lock); 168391ed5349SWolfram Sang bus_for_each_drv(&i2c_bus_type, NULL, adap, 168491ed5349SWolfram Sang __process_removed_adapter); 168591ed5349SWolfram Sang mutex_unlock(&core_lock); 168691ed5349SWolfram Sang 168791ed5349SWolfram Sang /* Remove devices instantiated from sysfs */ 168891ed5349SWolfram Sang mutex_lock_nested(&adap->userspace_clients_lock, 168991ed5349SWolfram Sang i2c_adapter_depth(adap)); 169091ed5349SWolfram Sang list_for_each_entry_safe(client, next, &adap->userspace_clients, 169191ed5349SWolfram Sang detected) { 169291ed5349SWolfram Sang dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, 169391ed5349SWolfram Sang client->addr); 169491ed5349SWolfram Sang list_del(&client->detected); 169591ed5349SWolfram Sang i2c_unregister_device(client); 169691ed5349SWolfram Sang } 169791ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 169891ed5349SWolfram Sang 169991ed5349SWolfram Sang /* Detach any active clients. This can't fail, thus we do not 170091ed5349SWolfram Sang * check the returned value. This is a two-pass process, because 170191ed5349SWolfram Sang * we can't remove the dummy devices during the first pass: they 170291ed5349SWolfram Sang * could have been instantiated by real devices wishing to clean 170391ed5349SWolfram Sang * them up properly, so we give them a chance to do that first. */ 170491ed5349SWolfram Sang device_for_each_child(&adap->dev, NULL, __unregister_client); 170591ed5349SWolfram Sang device_for_each_child(&adap->dev, NULL, __unregister_dummy); 170691ed5349SWolfram Sang 170791ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 170891ed5349SWolfram Sang class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, 170991ed5349SWolfram Sang adap->dev.parent); 171091ed5349SWolfram Sang #endif 171191ed5349SWolfram Sang 171291ed5349SWolfram Sang /* device name is gone after device_unregister */ 171391ed5349SWolfram Sang dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); 171491ed5349SWolfram Sang 171591ed5349SWolfram Sang pm_runtime_disable(&adap->dev); 171691ed5349SWolfram Sang 171791ed5349SWolfram Sang i2c_host_notify_irq_teardown(adap); 171891ed5349SWolfram Sang 171991ed5349SWolfram Sang /* wait until all references to the device are gone 172091ed5349SWolfram Sang * 172191ed5349SWolfram Sang * FIXME: This is old code and should ideally be replaced by an 172291ed5349SWolfram Sang * alternative which results in decoupling the lifetime of the struct 172391ed5349SWolfram Sang * device from the i2c_adapter, like spi or netdev do. Any solution 172491ed5349SWolfram Sang * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! 172591ed5349SWolfram Sang */ 172691ed5349SWolfram Sang init_completion(&adap->dev_released); 172791ed5349SWolfram Sang device_unregister(&adap->dev); 172891ed5349SWolfram Sang wait_for_completion(&adap->dev_released); 172991ed5349SWolfram Sang 173091ed5349SWolfram Sang /* free bus id */ 173191ed5349SWolfram Sang mutex_lock(&core_lock); 173291ed5349SWolfram Sang idr_remove(&i2c_adapter_idr, adap->nr); 173391ed5349SWolfram Sang mutex_unlock(&core_lock); 173491ed5349SWolfram Sang 173591ed5349SWolfram Sang /* Clear the device structure in case this adapter is ever going to be 173691ed5349SWolfram Sang added again */ 173791ed5349SWolfram Sang memset(&adap->dev, 0, sizeof(adap->dev)); 173891ed5349SWolfram Sang } 173991ed5349SWolfram Sang EXPORT_SYMBOL(i2c_del_adapter); 174091ed5349SWolfram Sang 174107740c92SYicong Yang static void devm_i2c_del_adapter(void *adapter) 174207740c92SYicong Yang { 174307740c92SYicong Yang i2c_del_adapter(adapter); 174407740c92SYicong Yang } 174507740c92SYicong Yang 174607740c92SYicong Yang /** 174707740c92SYicong Yang * devm_i2c_add_adapter - device-managed variant of i2c_add_adapter() 174807740c92SYicong Yang * @dev: managing device for adding this I2C adapter 174907740c92SYicong Yang * @adapter: the adapter to add 175007740c92SYicong Yang * Context: can sleep 175107740c92SYicong Yang * 175207740c92SYicong Yang * Add adapter with dynamic bus number, same with i2c_add_adapter() 175307740c92SYicong Yang * but the adapter will be auto deleted on driver detach. 175407740c92SYicong Yang */ 175507740c92SYicong Yang int devm_i2c_add_adapter(struct device *dev, struct i2c_adapter *adapter) 175607740c92SYicong Yang { 175707740c92SYicong Yang int ret; 175807740c92SYicong Yang 175907740c92SYicong Yang ret = i2c_add_adapter(adapter); 176007740c92SYicong Yang if (ret) 176107740c92SYicong Yang return ret; 176207740c92SYicong Yang 176307740c92SYicong Yang return devm_add_action_or_reset(dev, devm_i2c_del_adapter, adapter); 176407740c92SYicong Yang } 176507740c92SYicong Yang EXPORT_SYMBOL_GPL(devm_i2c_add_adapter); 176607740c92SYicong Yang 1767def00b32SWolfram Sang static void i2c_parse_timing(struct device *dev, char *prop_name, u32 *cur_val_p, 1768def00b32SWolfram Sang u32 def_val, bool use_def) 1769def00b32SWolfram Sang { 1770def00b32SWolfram Sang int ret; 1771def00b32SWolfram Sang 1772def00b32SWolfram Sang ret = device_property_read_u32(dev, prop_name, cur_val_p); 1773def00b32SWolfram Sang if (ret && use_def) 1774def00b32SWolfram Sang *cur_val_p = def_val; 1775def00b32SWolfram Sang 1776def00b32SWolfram Sang dev_dbg(dev, "%s: %u\n", prop_name, *cur_val_p); 1777def00b32SWolfram Sang } 1778def00b32SWolfram Sang 177991ed5349SWolfram Sang /** 178091ed5349SWolfram Sang * i2c_parse_fw_timings - get I2C related timing parameters from firmware 178191ed5349SWolfram Sang * @dev: The device to scan for I2C timing properties 178291ed5349SWolfram Sang * @t: the i2c_timings struct to be filled with values 178391ed5349SWolfram Sang * @use_defaults: bool to use sane defaults derived from the I2C specification 1784263a5646SAndy Shevchenko * when properties are not found, otherwise don't update 178591ed5349SWolfram Sang * 178691ed5349SWolfram Sang * Scan the device for the generic I2C properties describing timing parameters 178791ed5349SWolfram Sang * for the signal and fill the given struct with the results. If a property was 178891ed5349SWolfram Sang * not found and use_defaults was true, then maximum timings are assumed which 178991ed5349SWolfram Sang * are derived from the I2C specification. If use_defaults is not used, the 1790263a5646SAndy Shevchenko * results will be as before, so drivers can apply their own defaults before 1791263a5646SAndy Shevchenko * calling this helper. The latter is mainly intended for avoiding regressions 1792263a5646SAndy Shevchenko * of existing drivers which want to switch to this function. New drivers 1793263a5646SAndy Shevchenko * almost always should use the defaults. 179491ed5349SWolfram Sang */ 179591ed5349SWolfram Sang void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) 179691ed5349SWolfram Sang { 1797def00b32SWolfram Sang bool u = use_defaults; 1798def00b32SWolfram Sang u32 d; 179991ed5349SWolfram Sang 1800def00b32SWolfram Sang i2c_parse_timing(dev, "clock-frequency", &t->bus_freq_hz, 1801def00b32SWolfram Sang I2C_MAX_STANDARD_MODE_FREQ, u); 180291ed5349SWolfram Sang 1803def00b32SWolfram Sang d = t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ ? 1000 : 1804def00b32SWolfram Sang t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; 1805def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns, d, u); 180691ed5349SWolfram Sang 1807def00b32SWolfram Sang d = t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; 1808def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns, d, u); 180991ed5349SWolfram Sang 1810def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-scl-internal-delay-ns", 1811def00b32SWolfram Sang &t->scl_int_delay_ns, 0, u); 1812def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns, 1813def00b32SWolfram Sang t->scl_fall_ns, u); 1814def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns, 0, u); 1815def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-digital-filter-width-ns", 1816def00b32SWolfram Sang &t->digital_filter_width_ns, 0, u); 1817def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-analog-filter-cutoff-frequency", 1818def00b32SWolfram Sang &t->analog_filter_cutoff_freq_hz, 0, u); 181991ed5349SWolfram Sang } 182091ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); 182191ed5349SWolfram Sang 182291ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 182391ed5349SWolfram Sang 1824edd7a563SWolfram Sang int i2c_for_each_dev(void *data, int (*fn)(struct device *dev, void *data)) 182591ed5349SWolfram Sang { 182691ed5349SWolfram Sang int res; 182791ed5349SWolfram Sang 182891ed5349SWolfram Sang mutex_lock(&core_lock); 182991ed5349SWolfram Sang res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); 183091ed5349SWolfram Sang mutex_unlock(&core_lock); 183191ed5349SWolfram Sang 183291ed5349SWolfram Sang return res; 183391ed5349SWolfram Sang } 183491ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_for_each_dev); 183591ed5349SWolfram Sang 183691ed5349SWolfram Sang static int __process_new_driver(struct device *dev, void *data) 183791ed5349SWolfram Sang { 183891ed5349SWolfram Sang if (dev->type != &i2c_adapter_type) 183991ed5349SWolfram Sang return 0; 184091ed5349SWolfram Sang return i2c_do_add_adapter(data, to_i2c_adapter(dev)); 184191ed5349SWolfram Sang } 184291ed5349SWolfram Sang 184391ed5349SWolfram Sang /* 184491ed5349SWolfram Sang * An i2c_driver is used with one or more i2c_client (device) nodes to access 184591ed5349SWolfram Sang * i2c slave chips, on a bus instance associated with some i2c_adapter. 184691ed5349SWolfram Sang */ 184791ed5349SWolfram Sang 184891ed5349SWolfram Sang int i2c_register_driver(struct module *owner, struct i2c_driver *driver) 184991ed5349SWolfram Sang { 185091ed5349SWolfram Sang int res; 185191ed5349SWolfram Sang 185291ed5349SWolfram Sang /* Can't register until after driver model init */ 185391ed5349SWolfram Sang if (WARN_ON(!is_registered)) 185491ed5349SWolfram Sang return -EAGAIN; 185591ed5349SWolfram Sang 185691ed5349SWolfram Sang /* add the driver to the list of i2c drivers in the driver core */ 185791ed5349SWolfram Sang driver->driver.owner = owner; 185891ed5349SWolfram Sang driver->driver.bus = &i2c_bus_type; 185991ed5349SWolfram Sang INIT_LIST_HEAD(&driver->clients); 186091ed5349SWolfram Sang 186191ed5349SWolfram Sang /* When registration returns, the driver core 186291ed5349SWolfram Sang * will have called probe() for all matching-but-unbound devices. 186391ed5349SWolfram Sang */ 186491ed5349SWolfram Sang res = driver_register(&driver->driver); 186591ed5349SWolfram Sang if (res) 186691ed5349SWolfram Sang return res; 186791ed5349SWolfram Sang 186891ed5349SWolfram Sang pr_debug("driver [%s] registered\n", driver->driver.name); 186991ed5349SWolfram Sang 187091ed5349SWolfram Sang /* Walk the adapters that are already present */ 187191ed5349SWolfram Sang i2c_for_each_dev(driver, __process_new_driver); 187291ed5349SWolfram Sang 187391ed5349SWolfram Sang return 0; 187491ed5349SWolfram Sang } 187591ed5349SWolfram Sang EXPORT_SYMBOL(i2c_register_driver); 187691ed5349SWolfram Sang 187791ed5349SWolfram Sang static int __process_removed_driver(struct device *dev, void *data) 187891ed5349SWolfram Sang { 187991ed5349SWolfram Sang if (dev->type == &i2c_adapter_type) 188091ed5349SWolfram Sang i2c_do_del_adapter(data, to_i2c_adapter(dev)); 188191ed5349SWolfram Sang return 0; 188291ed5349SWolfram Sang } 188391ed5349SWolfram Sang 188491ed5349SWolfram Sang /** 188591ed5349SWolfram Sang * i2c_del_driver - unregister I2C driver 188691ed5349SWolfram Sang * @driver: the driver being unregistered 188791ed5349SWolfram Sang * Context: can sleep 188891ed5349SWolfram Sang */ 188991ed5349SWolfram Sang void i2c_del_driver(struct i2c_driver *driver) 189091ed5349SWolfram Sang { 189191ed5349SWolfram Sang i2c_for_each_dev(driver, __process_removed_driver); 189291ed5349SWolfram Sang 189391ed5349SWolfram Sang driver_unregister(&driver->driver); 189491ed5349SWolfram Sang pr_debug("driver [%s] unregistered\n", driver->driver.name); 189591ed5349SWolfram Sang } 189691ed5349SWolfram Sang EXPORT_SYMBOL(i2c_del_driver); 189791ed5349SWolfram Sang 189891ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 189991ed5349SWolfram Sang 190091ed5349SWolfram Sang struct i2c_cmd_arg { 190191ed5349SWolfram Sang unsigned cmd; 190291ed5349SWolfram Sang void *arg; 190391ed5349SWolfram Sang }; 190491ed5349SWolfram Sang 190591ed5349SWolfram Sang static int i2c_cmd(struct device *dev, void *_arg) 190691ed5349SWolfram Sang { 190791ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 190891ed5349SWolfram Sang struct i2c_cmd_arg *arg = _arg; 190991ed5349SWolfram Sang struct i2c_driver *driver; 191091ed5349SWolfram Sang 191191ed5349SWolfram Sang if (!client || !client->dev.driver) 191291ed5349SWolfram Sang return 0; 191391ed5349SWolfram Sang 191491ed5349SWolfram Sang driver = to_i2c_driver(client->dev.driver); 191591ed5349SWolfram Sang if (driver->command) 191691ed5349SWolfram Sang driver->command(client, arg->cmd, arg->arg); 191791ed5349SWolfram Sang return 0; 191891ed5349SWolfram Sang } 191991ed5349SWolfram Sang 192091ed5349SWolfram Sang void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) 192191ed5349SWolfram Sang { 192291ed5349SWolfram Sang struct i2c_cmd_arg cmd_arg; 192391ed5349SWolfram Sang 192491ed5349SWolfram Sang cmd_arg.cmd = cmd; 192591ed5349SWolfram Sang cmd_arg.arg = arg; 192691ed5349SWolfram Sang device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); 192791ed5349SWolfram Sang } 192891ed5349SWolfram Sang EXPORT_SYMBOL(i2c_clients_command); 192991ed5349SWolfram Sang 193091ed5349SWolfram Sang static int __init i2c_init(void) 193191ed5349SWolfram Sang { 193291ed5349SWolfram Sang int retval; 193391ed5349SWolfram Sang 193491ed5349SWolfram Sang retval = of_alias_get_highest_id("i2c"); 193591ed5349SWolfram Sang 193691ed5349SWolfram Sang down_write(&__i2c_board_lock); 193791ed5349SWolfram Sang if (retval >= __i2c_first_dynamic_bus_num) 193891ed5349SWolfram Sang __i2c_first_dynamic_bus_num = retval + 1; 193991ed5349SWolfram Sang up_write(&__i2c_board_lock); 194091ed5349SWolfram Sang 194191ed5349SWolfram Sang retval = bus_register(&i2c_bus_type); 194291ed5349SWolfram Sang if (retval) 194391ed5349SWolfram Sang return retval; 194491ed5349SWolfram Sang 194591ed5349SWolfram Sang is_registered = true; 194691ed5349SWolfram Sang 194791ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 194891ed5349SWolfram Sang i2c_adapter_compat_class = class_compat_register("i2c-adapter"); 194991ed5349SWolfram Sang if (!i2c_adapter_compat_class) { 195091ed5349SWolfram Sang retval = -ENOMEM; 195191ed5349SWolfram Sang goto bus_err; 195291ed5349SWolfram Sang } 195391ed5349SWolfram Sang #endif 195491ed5349SWolfram Sang retval = i2c_add_driver(&dummy_driver); 195591ed5349SWolfram Sang if (retval) 195691ed5349SWolfram Sang goto class_err; 195791ed5349SWolfram Sang 195891ed5349SWolfram Sang if (IS_ENABLED(CONFIG_OF_DYNAMIC)) 195991ed5349SWolfram Sang WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); 196091ed5349SWolfram Sang if (IS_ENABLED(CONFIG_ACPI)) 196191ed5349SWolfram Sang WARN_ON(acpi_reconfig_notifier_register(&i2c_acpi_notifier)); 196291ed5349SWolfram Sang 196391ed5349SWolfram Sang return 0; 196491ed5349SWolfram Sang 196591ed5349SWolfram Sang class_err: 196691ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 196791ed5349SWolfram Sang class_compat_unregister(i2c_adapter_compat_class); 196891ed5349SWolfram Sang bus_err: 196991ed5349SWolfram Sang #endif 197091ed5349SWolfram Sang is_registered = false; 197191ed5349SWolfram Sang bus_unregister(&i2c_bus_type); 197291ed5349SWolfram Sang return retval; 197391ed5349SWolfram Sang } 197491ed5349SWolfram Sang 197591ed5349SWolfram Sang static void __exit i2c_exit(void) 197691ed5349SWolfram Sang { 197791ed5349SWolfram Sang if (IS_ENABLED(CONFIG_ACPI)) 197891ed5349SWolfram Sang WARN_ON(acpi_reconfig_notifier_unregister(&i2c_acpi_notifier)); 197991ed5349SWolfram Sang if (IS_ENABLED(CONFIG_OF_DYNAMIC)) 198091ed5349SWolfram Sang WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); 198191ed5349SWolfram Sang i2c_del_driver(&dummy_driver); 198291ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 198391ed5349SWolfram Sang class_compat_unregister(i2c_adapter_compat_class); 198491ed5349SWolfram Sang #endif 198591ed5349SWolfram Sang bus_unregister(&i2c_bus_type); 198691ed5349SWolfram Sang tracepoint_synchronize_unregister(); 198791ed5349SWolfram Sang } 198891ed5349SWolfram Sang 198991ed5349SWolfram Sang /* We must initialize early, because some subsystems register i2c drivers 199091ed5349SWolfram Sang * in subsys_initcall() code, but are linked (and initialized) before i2c. 199191ed5349SWolfram Sang */ 199291ed5349SWolfram Sang postcore_initcall(i2c_init); 199391ed5349SWolfram Sang module_exit(i2c_exit); 199491ed5349SWolfram Sang 199591ed5349SWolfram Sang /* ---------------------------------------------------- 199691ed5349SWolfram Sang * the functional interface to the i2c busses. 199791ed5349SWolfram Sang * ---------------------------------------------------- 199891ed5349SWolfram Sang */ 199991ed5349SWolfram Sang 200091ed5349SWolfram Sang /* Check if val is exceeding the quirk IFF quirk is non 0 */ 200191ed5349SWolfram Sang #define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) 200291ed5349SWolfram Sang 200391ed5349SWolfram Sang static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) 200491ed5349SWolfram Sang { 200591ed5349SWolfram Sang dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", 200691ed5349SWolfram Sang err_msg, msg->addr, msg->len, 200791ed5349SWolfram Sang msg->flags & I2C_M_RD ? "read" : "write"); 200891ed5349SWolfram Sang return -EOPNOTSUPP; 200991ed5349SWolfram Sang } 201091ed5349SWolfram Sang 201191ed5349SWolfram Sang static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 201291ed5349SWolfram Sang { 201391ed5349SWolfram Sang const struct i2c_adapter_quirks *q = adap->quirks; 201491ed5349SWolfram Sang int max_num = q->max_num_msgs, i; 201591ed5349SWolfram Sang bool do_len_check = true; 201691ed5349SWolfram Sang 201791ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB) { 201891ed5349SWolfram Sang max_num = 2; 201991ed5349SWolfram Sang 202091ed5349SWolfram Sang /* special checks for combined messages */ 202191ed5349SWolfram Sang if (num == 2) { 202291ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) 202391ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); 202491ed5349SWolfram Sang 202591ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) 202691ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); 202791ed5349SWolfram Sang 202891ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) 202991ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); 203091ed5349SWolfram Sang 203191ed5349SWolfram Sang if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) 203291ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "msg too long"); 203391ed5349SWolfram Sang 203491ed5349SWolfram Sang if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) 203591ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[1], "msg too long"); 203691ed5349SWolfram Sang 203791ed5349SWolfram Sang do_len_check = false; 203891ed5349SWolfram Sang } 203991ed5349SWolfram Sang } 204091ed5349SWolfram Sang 204191ed5349SWolfram Sang if (i2c_quirk_exceeded(num, max_num)) 204291ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "too many messages"); 204391ed5349SWolfram Sang 204491ed5349SWolfram Sang for (i = 0; i < num; i++) { 204591ed5349SWolfram Sang u16 len = msgs[i].len; 204691ed5349SWolfram Sang 204791ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) { 204891ed5349SWolfram Sang if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) 204991ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[i], "msg too long"); 2050d9cfe2ceSWolfram Sang 2051d9cfe2ceSWolfram Sang if (q->flags & I2C_AQ_NO_ZERO_LEN_READ && len == 0) 2052d9cfe2ceSWolfram Sang return i2c_quirk_error(adap, &msgs[i], "no zero length"); 205391ed5349SWolfram Sang } else { 205491ed5349SWolfram Sang if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) 205591ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[i], "msg too long"); 2056d9cfe2ceSWolfram Sang 2057d9cfe2ceSWolfram Sang if (q->flags & I2C_AQ_NO_ZERO_LEN_WRITE && len == 0) 2058d9cfe2ceSWolfram Sang return i2c_quirk_error(adap, &msgs[i], "no zero length"); 205991ed5349SWolfram Sang } 206091ed5349SWolfram Sang } 206191ed5349SWolfram Sang 206291ed5349SWolfram Sang return 0; 206391ed5349SWolfram Sang } 206491ed5349SWolfram Sang 206591ed5349SWolfram Sang /** 206691ed5349SWolfram Sang * __i2c_transfer - unlocked flavor of i2c_transfer 206791ed5349SWolfram Sang * @adap: Handle to I2C bus 206891ed5349SWolfram Sang * @msgs: One or more messages to execute before STOP is issued to 206991ed5349SWolfram Sang * terminate the operation; each message begins with a START. 207091ed5349SWolfram Sang * @num: Number of messages to be executed. 207191ed5349SWolfram Sang * 207291ed5349SWolfram Sang * Returns negative errno, else the number of messages executed. 207391ed5349SWolfram Sang * 207491ed5349SWolfram Sang * Adapter lock must be held when calling this function. No debug logging 207591ed5349SWolfram Sang * takes place. adap->algo->master_xfer existence isn't checked. 207691ed5349SWolfram Sang */ 207791ed5349SWolfram Sang int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 207891ed5349SWolfram Sang { 207991ed5349SWolfram Sang unsigned long orig_jiffies; 208091ed5349SWolfram Sang int ret, try; 208191ed5349SWolfram Sang 20821eace834SArd Biesheuvel if (WARN_ON(!msgs || num < 1)) 20831eace834SArd Biesheuvel return -EINVAL; 20845d756112SWolfram Sang 20855d756112SWolfram Sang ret = __i2c_check_suspended(adap); 20865d756112SWolfram Sang if (ret) 20875d756112SWolfram Sang return ret; 20881eace834SArd Biesheuvel 208991ed5349SWolfram Sang if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) 209091ed5349SWolfram Sang return -EOPNOTSUPP; 209191ed5349SWolfram Sang 209250888b01SDavidlohr Bueso /* 209350888b01SDavidlohr Bueso * i2c_trace_msg_key gets enabled when tracepoint i2c_transfer gets 209491ed5349SWolfram Sang * enabled. This is an efficient way of keeping the for-loop from 209591ed5349SWolfram Sang * being executed when not needed. 209691ed5349SWolfram Sang */ 209750888b01SDavidlohr Bueso if (static_branch_unlikely(&i2c_trace_msg_key)) { 209891ed5349SWolfram Sang int i; 209991ed5349SWolfram Sang for (i = 0; i < num; i++) 210091ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) 210191ed5349SWolfram Sang trace_i2c_read(adap, &msgs[i], i); 210291ed5349SWolfram Sang else 210391ed5349SWolfram Sang trace_i2c_write(adap, &msgs[i], i); 210491ed5349SWolfram Sang } 210591ed5349SWolfram Sang 210691ed5349SWolfram Sang /* Retry automatically on arbitration loss */ 210791ed5349SWolfram Sang orig_jiffies = jiffies; 210891ed5349SWolfram Sang for (ret = 0, try = 0; try <= adap->retries; try++) { 210963b96983SWolfram Sang if (i2c_in_atomic_xfer_mode() && adap->algo->master_xfer_atomic) 211063b96983SWolfram Sang ret = adap->algo->master_xfer_atomic(adap, msgs, num); 211163b96983SWolfram Sang else 211291ed5349SWolfram Sang ret = adap->algo->master_xfer(adap, msgs, num); 211363b96983SWolfram Sang 211491ed5349SWolfram Sang if (ret != -EAGAIN) 211591ed5349SWolfram Sang break; 211691ed5349SWolfram Sang if (time_after(jiffies, orig_jiffies + adap->timeout)) 211791ed5349SWolfram Sang break; 211891ed5349SWolfram Sang } 211991ed5349SWolfram Sang 212050888b01SDavidlohr Bueso if (static_branch_unlikely(&i2c_trace_msg_key)) { 212191ed5349SWolfram Sang int i; 212291ed5349SWolfram Sang for (i = 0; i < ret; i++) 212391ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) 212491ed5349SWolfram Sang trace_i2c_reply(adap, &msgs[i], i); 21254a3f7691SAhbong Chang trace_i2c_result(adap, num, ret); 212691ed5349SWolfram Sang } 212791ed5349SWolfram Sang 212891ed5349SWolfram Sang return ret; 212991ed5349SWolfram Sang } 213091ed5349SWolfram Sang EXPORT_SYMBOL(__i2c_transfer); 213191ed5349SWolfram Sang 213291ed5349SWolfram Sang /** 213391ed5349SWolfram Sang * i2c_transfer - execute a single or combined I2C message 213491ed5349SWolfram Sang * @adap: Handle to I2C bus 213591ed5349SWolfram Sang * @msgs: One or more messages to execute before STOP is issued to 213691ed5349SWolfram Sang * terminate the operation; each message begins with a START. 213791ed5349SWolfram Sang * @num: Number of messages to be executed. 213891ed5349SWolfram Sang * 213991ed5349SWolfram Sang * Returns negative errno, else the number of messages executed. 214091ed5349SWolfram Sang * 214191ed5349SWolfram Sang * Note that there is no requirement that each message be sent to 214291ed5349SWolfram Sang * the same slave address, although that is the most common model. 214391ed5349SWolfram Sang */ 214491ed5349SWolfram Sang int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 214591ed5349SWolfram Sang { 214691ed5349SWolfram Sang int ret; 214791ed5349SWolfram Sang 2148cc52612eSWolfram Sang if (!adap->algo->master_xfer) { 2149cc52612eSWolfram Sang dev_dbg(&adap->dev, "I2C level transfers not supported\n"); 2150cc52612eSWolfram Sang return -EOPNOTSUPP; 2151cc52612eSWolfram Sang } 2152cc52612eSWolfram Sang 215391ed5349SWolfram Sang /* REVISIT the fault reporting model here is weak: 215491ed5349SWolfram Sang * 215591ed5349SWolfram Sang * - When we get an error after receiving N bytes from a slave, 215691ed5349SWolfram Sang * there is no way to report "N". 215791ed5349SWolfram Sang * 215891ed5349SWolfram Sang * - When we get a NAK after transmitting N bytes to a slave, 215991ed5349SWolfram Sang * there is no way to report "N" ... or to let the master 216091ed5349SWolfram Sang * continue executing the rest of this combined message, if 216191ed5349SWolfram Sang * that's the appropriate response. 216291ed5349SWolfram Sang * 216391ed5349SWolfram Sang * - When for example "num" is two and we successfully complete 216491ed5349SWolfram Sang * the first message but get an error part way through the 216591ed5349SWolfram Sang * second, it's unclear whether that should be reported as 216691ed5349SWolfram Sang * one (discarding status on the second message) or errno 216791ed5349SWolfram Sang * (discarding status on the first one). 216891ed5349SWolfram Sang */ 216983c42212SWolfram Sang ret = __i2c_lock_bus_helper(adap); 217083c42212SWolfram Sang if (ret) 217183c42212SWolfram Sang return ret; 217291ed5349SWolfram Sang 217391ed5349SWolfram Sang ret = __i2c_transfer(adap, msgs, num); 217491ed5349SWolfram Sang i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); 217591ed5349SWolfram Sang 217691ed5349SWolfram Sang return ret; 217791ed5349SWolfram Sang } 217891ed5349SWolfram Sang EXPORT_SYMBOL(i2c_transfer); 217991ed5349SWolfram Sang 218091ed5349SWolfram Sang /** 21818a91732bSWolfram Sang * i2c_transfer_buffer_flags - issue a single I2C message transferring data 21828a91732bSWolfram Sang * to/from a buffer 218391ed5349SWolfram Sang * @client: Handle to slave device 21848a91732bSWolfram Sang * @buf: Where the data is stored 21858a91732bSWolfram Sang * @count: How many bytes to transfer, must be less than 64k since msg.len is u16 21868a91732bSWolfram Sang * @flags: The flags to be used for the message, e.g. I2C_M_RD for reads 218791ed5349SWolfram Sang * 21888a91732bSWolfram Sang * Returns negative errno, or else the number of bytes transferred. 218991ed5349SWolfram Sang */ 21908a91732bSWolfram Sang int i2c_transfer_buffer_flags(const struct i2c_client *client, char *buf, 21918a91732bSWolfram Sang int count, u16 flags) 219291ed5349SWolfram Sang { 219391ed5349SWolfram Sang int ret; 21948a91732bSWolfram Sang struct i2c_msg msg = { 21958a91732bSWolfram Sang .addr = client->addr, 21968a91732bSWolfram Sang .flags = flags | (client->flags & I2C_M_TEN), 21978a91732bSWolfram Sang .len = count, 21988a91732bSWolfram Sang .buf = buf, 21998a91732bSWolfram Sang }; 220091ed5349SWolfram Sang 22018a91732bSWolfram Sang ret = i2c_transfer(client->adapter, &msg, 1); 220291ed5349SWolfram Sang 220391ed5349SWolfram Sang /* 22048a91732bSWolfram Sang * If everything went ok (i.e. 1 msg transferred), return #bytes 22058a91732bSWolfram Sang * transferred, else error code. 220691ed5349SWolfram Sang */ 220791ed5349SWolfram Sang return (ret == 1) ? count : ret; 220891ed5349SWolfram Sang } 22098a91732bSWolfram Sang EXPORT_SYMBOL(i2c_transfer_buffer_flags); 221091ed5349SWolfram Sang 2211dde67eb1SPeter Rosin /** 2212dde67eb1SPeter Rosin * i2c_get_device_id - get manufacturer, part id and die revision of a device 2213dde67eb1SPeter Rosin * @client: The device to query 2214dde67eb1SPeter Rosin * @id: The queried information 2215dde67eb1SPeter Rosin * 2216dde67eb1SPeter Rosin * Returns negative errno on error, zero on success. 2217dde67eb1SPeter Rosin */ 2218dde67eb1SPeter Rosin int i2c_get_device_id(const struct i2c_client *client, 2219dde67eb1SPeter Rosin struct i2c_device_identity *id) 2220dde67eb1SPeter Rosin { 2221dde67eb1SPeter Rosin struct i2c_adapter *adap = client->adapter; 2222dde67eb1SPeter Rosin union i2c_smbus_data raw_id; 2223dde67eb1SPeter Rosin int ret; 2224dde67eb1SPeter Rosin 2225dde67eb1SPeter Rosin if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) 2226dde67eb1SPeter Rosin return -EOPNOTSUPP; 2227dde67eb1SPeter Rosin 2228dde67eb1SPeter Rosin raw_id.block[0] = 3; 2229dde67eb1SPeter Rosin ret = i2c_smbus_xfer(adap, I2C_ADDR_DEVICE_ID, 0, 2230dde67eb1SPeter Rosin I2C_SMBUS_READ, client->addr << 1, 2231dde67eb1SPeter Rosin I2C_SMBUS_I2C_BLOCK_DATA, &raw_id); 2232dde67eb1SPeter Rosin if (ret) 2233dde67eb1SPeter Rosin return ret; 2234dde67eb1SPeter Rosin 2235dde67eb1SPeter Rosin id->manufacturer_id = (raw_id.block[1] << 4) | (raw_id.block[2] >> 4); 2236dde67eb1SPeter Rosin id->part_id = ((raw_id.block[2] & 0xf) << 5) | (raw_id.block[3] >> 3); 2237dde67eb1SPeter Rosin id->die_revision = raw_id.block[3] & 0x7; 2238dde67eb1SPeter Rosin return 0; 2239dde67eb1SPeter Rosin } 2240dde67eb1SPeter Rosin EXPORT_SYMBOL_GPL(i2c_get_device_id); 2241dde67eb1SPeter Rosin 224291ed5349SWolfram Sang /* ---------------------------------------------------- 224391ed5349SWolfram Sang * the i2c address scanning function 224491ed5349SWolfram Sang * Will not work for 10-bit addresses! 224591ed5349SWolfram Sang * ---------------------------------------------------- 224691ed5349SWolfram Sang */ 224791ed5349SWolfram Sang 224891ed5349SWolfram Sang /* 224991ed5349SWolfram Sang * Legacy default probe function, mostly relevant for SMBus. The default 225091ed5349SWolfram Sang * probe method is a quick write, but it is known to corrupt the 24RF08 225191ed5349SWolfram Sang * EEPROMs due to a state machine bug, and could also irreversibly 225291ed5349SWolfram Sang * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, 225391ed5349SWolfram Sang * we use a short byte read instead. Also, some bus drivers don't implement 225491ed5349SWolfram Sang * quick write, so we fallback to a byte read in that case too. 225591ed5349SWolfram Sang * On x86, there is another special case for FSC hardware monitoring chips, 225691ed5349SWolfram Sang * which want regular byte reads (address 0x73.) Fortunately, these are the 225791ed5349SWolfram Sang * only known chips using this I2C address on PC hardware. 225891ed5349SWolfram Sang * Returns 1 if probe succeeded, 0 if not. 225991ed5349SWolfram Sang */ 226091ed5349SWolfram Sang static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) 226191ed5349SWolfram Sang { 226291ed5349SWolfram Sang int err; 226391ed5349SWolfram Sang union i2c_smbus_data dummy; 226491ed5349SWolfram Sang 226591ed5349SWolfram Sang #ifdef CONFIG_X86 226691ed5349SWolfram Sang if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) 226791ed5349SWolfram Sang && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) 226891ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 226991ed5349SWolfram Sang I2C_SMBUS_BYTE_DATA, &dummy); 227091ed5349SWolfram Sang else 227191ed5349SWolfram Sang #endif 227291ed5349SWolfram Sang if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) 227391ed5349SWolfram Sang && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) 227491ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, 227591ed5349SWolfram Sang I2C_SMBUS_QUICK, NULL); 227691ed5349SWolfram Sang else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) 227791ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 227891ed5349SWolfram Sang I2C_SMBUS_BYTE, &dummy); 227991ed5349SWolfram Sang else { 228091ed5349SWolfram Sang dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", 228191ed5349SWolfram Sang addr); 228291ed5349SWolfram Sang err = -EOPNOTSUPP; 228391ed5349SWolfram Sang } 228491ed5349SWolfram Sang 228591ed5349SWolfram Sang return err >= 0; 228691ed5349SWolfram Sang } 228791ed5349SWolfram Sang 228891ed5349SWolfram Sang static int i2c_detect_address(struct i2c_client *temp_client, 228991ed5349SWolfram Sang struct i2c_driver *driver) 229091ed5349SWolfram Sang { 229191ed5349SWolfram Sang struct i2c_board_info info; 229291ed5349SWolfram Sang struct i2c_adapter *adapter = temp_client->adapter; 229391ed5349SWolfram Sang int addr = temp_client->addr; 229491ed5349SWolfram Sang int err; 229591ed5349SWolfram Sang 229691ed5349SWolfram Sang /* Make sure the address is valid */ 229791ed5349SWolfram Sang err = i2c_check_7bit_addr_validity_strict(addr); 229891ed5349SWolfram Sang if (err) { 229991ed5349SWolfram Sang dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", 230091ed5349SWolfram Sang addr); 230191ed5349SWolfram Sang return err; 230291ed5349SWolfram Sang } 230391ed5349SWolfram Sang 230491ed5349SWolfram Sang /* Skip if already in use (7 bit, no need to encode flags) */ 230591ed5349SWolfram Sang if (i2c_check_addr_busy(adapter, addr)) 230691ed5349SWolfram Sang return 0; 230791ed5349SWolfram Sang 230891ed5349SWolfram Sang /* Make sure there is something at this address */ 230991ed5349SWolfram Sang if (!i2c_default_probe(adapter, addr)) 231091ed5349SWolfram Sang return 0; 231191ed5349SWolfram Sang 231291ed5349SWolfram Sang /* Finally call the custom detection function */ 231391ed5349SWolfram Sang memset(&info, 0, sizeof(struct i2c_board_info)); 231491ed5349SWolfram Sang info.addr = addr; 231591ed5349SWolfram Sang err = driver->detect(temp_client, &info); 231691ed5349SWolfram Sang if (err) { 231791ed5349SWolfram Sang /* -ENODEV is returned if the detection fails. We catch it 231891ed5349SWolfram Sang here as this isn't an error. */ 231991ed5349SWolfram Sang return err == -ENODEV ? 0 : err; 232091ed5349SWolfram Sang } 232191ed5349SWolfram Sang 232291ed5349SWolfram Sang /* Consistency check */ 232391ed5349SWolfram Sang if (info.type[0] == '\0') { 232491ed5349SWolfram Sang dev_err(&adapter->dev, 232591ed5349SWolfram Sang "%s detection function provided no name for 0x%x\n", 232691ed5349SWolfram Sang driver->driver.name, addr); 232791ed5349SWolfram Sang } else { 232891ed5349SWolfram Sang struct i2c_client *client; 232991ed5349SWolfram Sang 233091ed5349SWolfram Sang /* Detection succeeded, instantiate the device */ 233191ed5349SWolfram Sang if (adapter->class & I2C_CLASS_DEPRECATED) 233291ed5349SWolfram Sang dev_warn(&adapter->dev, 233391ed5349SWolfram Sang "This adapter will soon drop class based instantiation of devices. " 233491ed5349SWolfram Sang "Please make sure client 0x%02x gets instantiated by other means. " 2335ccf988b6SMauro Carvalho Chehab "Check 'Documentation/i2c/instantiating-devices.rst' for details.\n", 233691ed5349SWolfram Sang info.addr); 233791ed5349SWolfram Sang 233891ed5349SWolfram Sang dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", 233991ed5349SWolfram Sang info.type, info.addr); 234087e07437SWolfram Sang client = i2c_new_client_device(adapter, &info); 234187e07437SWolfram Sang if (!IS_ERR(client)) 234291ed5349SWolfram Sang list_add_tail(&client->detected, &driver->clients); 234391ed5349SWolfram Sang else 234491ed5349SWolfram Sang dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", 234591ed5349SWolfram Sang info.type, info.addr); 234691ed5349SWolfram Sang } 234791ed5349SWolfram Sang return 0; 234891ed5349SWolfram Sang } 234991ed5349SWolfram Sang 235091ed5349SWolfram Sang static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) 235191ed5349SWolfram Sang { 235291ed5349SWolfram Sang const unsigned short *address_list; 235391ed5349SWolfram Sang struct i2c_client *temp_client; 235491ed5349SWolfram Sang int i, err = 0; 235591ed5349SWolfram Sang 235691ed5349SWolfram Sang address_list = driver->address_list; 235791ed5349SWolfram Sang if (!driver->detect || !address_list) 235891ed5349SWolfram Sang return 0; 235991ed5349SWolfram Sang 236091ed5349SWolfram Sang /* Warn that the adapter lost class based instantiation */ 236191ed5349SWolfram Sang if (adapter->class == I2C_CLASS_DEPRECATED) { 236291ed5349SWolfram Sang dev_dbg(&adapter->dev, 236391ed5349SWolfram Sang "This adapter dropped support for I2C classes and won't auto-detect %s devices anymore. " 2364ccf988b6SMauro Carvalho Chehab "If you need it, check 'Documentation/i2c/instantiating-devices.rst' for alternatives.\n", 236591ed5349SWolfram Sang driver->driver.name); 236691ed5349SWolfram Sang return 0; 236791ed5349SWolfram Sang } 236891ed5349SWolfram Sang 236991ed5349SWolfram Sang /* Stop here if the classes do not match */ 237091ed5349SWolfram Sang if (!(adapter->class & driver->class)) 237191ed5349SWolfram Sang return 0; 237291ed5349SWolfram Sang 237391ed5349SWolfram Sang /* Set up a temporary client to help detect callback */ 237491ed5349SWolfram Sang temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); 237591ed5349SWolfram Sang if (!temp_client) 237691ed5349SWolfram Sang return -ENOMEM; 237791ed5349SWolfram Sang temp_client->adapter = adapter; 237891ed5349SWolfram Sang 237991ed5349SWolfram Sang for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { 238091ed5349SWolfram Sang dev_dbg(&adapter->dev, 238191ed5349SWolfram Sang "found normal entry for adapter %d, addr 0x%02x\n", 2382dd4f2ca9SWolfram Sang i2c_adapter_id(adapter), address_list[i]); 238391ed5349SWolfram Sang temp_client->addr = address_list[i]; 238491ed5349SWolfram Sang err = i2c_detect_address(temp_client, driver); 238591ed5349SWolfram Sang if (unlikely(err)) 238691ed5349SWolfram Sang break; 238791ed5349SWolfram Sang } 238891ed5349SWolfram Sang 238991ed5349SWolfram Sang kfree(temp_client); 239091ed5349SWolfram Sang return err; 239191ed5349SWolfram Sang } 239291ed5349SWolfram Sang 239391ed5349SWolfram Sang int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) 239491ed5349SWolfram Sang { 239591ed5349SWolfram Sang return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 239691ed5349SWolfram Sang I2C_SMBUS_QUICK, NULL) >= 0; 239791ed5349SWolfram Sang } 239891ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); 239991ed5349SWolfram Sang 240091ed5349SWolfram Sang struct i2c_client * 2401c1d08475SWolfram Sang i2c_new_scanned_device(struct i2c_adapter *adap, 240291ed5349SWolfram Sang struct i2c_board_info *info, 240391ed5349SWolfram Sang unsigned short const *addr_list, 2404edd7a563SWolfram Sang int (*probe)(struct i2c_adapter *adap, unsigned short addr)) 240591ed5349SWolfram Sang { 240691ed5349SWolfram Sang int i; 240791ed5349SWolfram Sang 240891ed5349SWolfram Sang if (!probe) 240991ed5349SWolfram Sang probe = i2c_default_probe; 241091ed5349SWolfram Sang 241191ed5349SWolfram Sang for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { 241291ed5349SWolfram Sang /* Check address validity */ 241391ed5349SWolfram Sang if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { 241491ed5349SWolfram Sang dev_warn(&adap->dev, "Invalid 7-bit address 0x%02x\n", 241591ed5349SWolfram Sang addr_list[i]); 241691ed5349SWolfram Sang continue; 241791ed5349SWolfram Sang } 241891ed5349SWolfram Sang 241991ed5349SWolfram Sang /* Check address availability (7 bit, no need to encode flags) */ 242091ed5349SWolfram Sang if (i2c_check_addr_busy(adap, addr_list[i])) { 242191ed5349SWolfram Sang dev_dbg(&adap->dev, 242291ed5349SWolfram Sang "Address 0x%02x already in use, not probing\n", 242391ed5349SWolfram Sang addr_list[i]); 242491ed5349SWolfram Sang continue; 242591ed5349SWolfram Sang } 242691ed5349SWolfram Sang 242791ed5349SWolfram Sang /* Test address responsiveness */ 242891ed5349SWolfram Sang if (probe(adap, addr_list[i])) 242991ed5349SWolfram Sang break; 243091ed5349SWolfram Sang } 243191ed5349SWolfram Sang 243291ed5349SWolfram Sang if (addr_list[i] == I2C_CLIENT_END) { 243391ed5349SWolfram Sang dev_dbg(&adap->dev, "Probing failed, no device found\n"); 2434c1d08475SWolfram Sang return ERR_PTR(-ENODEV); 243591ed5349SWolfram Sang } 243691ed5349SWolfram Sang 243791ed5349SWolfram Sang info->addr = addr_list[i]; 2438c1d08475SWolfram Sang return i2c_new_client_device(adap, info); 2439c1d08475SWolfram Sang } 2440c1d08475SWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_scanned_device); 2441c1d08475SWolfram Sang 244291ed5349SWolfram Sang struct i2c_adapter *i2c_get_adapter(int nr) 244391ed5349SWolfram Sang { 244491ed5349SWolfram Sang struct i2c_adapter *adapter; 244591ed5349SWolfram Sang 244691ed5349SWolfram Sang mutex_lock(&core_lock); 244791ed5349SWolfram Sang adapter = idr_find(&i2c_adapter_idr, nr); 244891ed5349SWolfram Sang if (!adapter) 244991ed5349SWolfram Sang goto exit; 245091ed5349SWolfram Sang 245191ed5349SWolfram Sang if (try_module_get(adapter->owner)) 245291ed5349SWolfram Sang get_device(&adapter->dev); 245391ed5349SWolfram Sang else 245491ed5349SWolfram Sang adapter = NULL; 245591ed5349SWolfram Sang 245691ed5349SWolfram Sang exit: 245791ed5349SWolfram Sang mutex_unlock(&core_lock); 245891ed5349SWolfram Sang return adapter; 245991ed5349SWolfram Sang } 246091ed5349SWolfram Sang EXPORT_SYMBOL(i2c_get_adapter); 246191ed5349SWolfram Sang 246291ed5349SWolfram Sang void i2c_put_adapter(struct i2c_adapter *adap) 246391ed5349SWolfram Sang { 246491ed5349SWolfram Sang if (!adap) 246591ed5349SWolfram Sang return; 246691ed5349SWolfram Sang 246791ed5349SWolfram Sang put_device(&adap->dev); 246891ed5349SWolfram Sang module_put(adap->owner); 246991ed5349SWolfram Sang } 247091ed5349SWolfram Sang EXPORT_SYMBOL(i2c_put_adapter); 247191ed5349SWolfram Sang 2472e94bc5d1SWolfram Sang /** 2473e94bc5d1SWolfram Sang * i2c_get_dma_safe_msg_buf() - get a DMA safe buffer for the given i2c_msg 2474e94bc5d1SWolfram Sang * @msg: the message to be checked 2475bf263c35SWolfram Sang * @threshold: the minimum number of bytes for which using DMA makes sense. 2476bf263c35SWolfram Sang * Should at least be 1. 2477e94bc5d1SWolfram Sang * 2478e94bc5d1SWolfram Sang * Return: NULL if a DMA safe buffer was not obtained. Use msg->buf with PIO. 2479e94bc5d1SWolfram Sang * Or a valid pointer to be used with DMA. After use, release it by 248034d1b82cSStephen Boyd * calling i2c_put_dma_safe_msg_buf(). 2481e94bc5d1SWolfram Sang * 2482e94bc5d1SWolfram Sang * This function must only be called from process context! 2483e94bc5d1SWolfram Sang */ 2484e94bc5d1SWolfram Sang u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold) 2485e94bc5d1SWolfram Sang { 2486bf263c35SWolfram Sang /* also skip 0-length msgs for bogus thresholds of 0 */ 2487bf263c35SWolfram Sang if (!threshold) 2488bf263c35SWolfram Sang pr_debug("DMA buffer for addr=0x%02x with length 0 is bogus\n", 2489bf263c35SWolfram Sang msg->addr); 2490bf263c35SWolfram Sang if (msg->len < threshold || msg->len == 0) 2491e94bc5d1SWolfram Sang return NULL; 2492e94bc5d1SWolfram Sang 2493e94bc5d1SWolfram Sang if (msg->flags & I2C_M_DMA_SAFE) 2494e94bc5d1SWolfram Sang return msg->buf; 2495e94bc5d1SWolfram Sang 2496e94bc5d1SWolfram Sang pr_debug("using bounce buffer for addr=0x%02x, len=%d\n", 2497e94bc5d1SWolfram Sang msg->addr, msg->len); 2498e94bc5d1SWolfram Sang 2499e94bc5d1SWolfram Sang if (msg->flags & I2C_M_RD) 2500e94bc5d1SWolfram Sang return kzalloc(msg->len, GFP_KERNEL); 2501e94bc5d1SWolfram Sang else 2502e94bc5d1SWolfram Sang return kmemdup(msg->buf, msg->len, GFP_KERNEL); 2503e94bc5d1SWolfram Sang } 2504e94bc5d1SWolfram Sang EXPORT_SYMBOL_GPL(i2c_get_dma_safe_msg_buf); 2505e94bc5d1SWolfram Sang 2506e94bc5d1SWolfram Sang /** 250782fe39a6SWolfram Sang * i2c_put_dma_safe_msg_buf - release DMA safe buffer and sync with i2c_msg 2508e94bc5d1SWolfram Sang * @buf: the buffer obtained from i2c_get_dma_safe_msg_buf(). May be NULL. 250982fe39a6SWolfram Sang * @msg: the message which the buffer corresponds to 251082fe39a6SWolfram Sang * @xferred: bool saying if the message was transferred 2511e94bc5d1SWolfram Sang */ 251282fe39a6SWolfram Sang void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred) 2513e94bc5d1SWolfram Sang { 2514e94bc5d1SWolfram Sang if (!buf || buf == msg->buf) 2515e94bc5d1SWolfram Sang return; 2516e94bc5d1SWolfram Sang 251782fe39a6SWolfram Sang if (xferred && msg->flags & I2C_M_RD) 2518e94bc5d1SWolfram Sang memcpy(msg->buf, buf, msg->len); 2519e94bc5d1SWolfram Sang 2520e94bc5d1SWolfram Sang kfree(buf); 2521e94bc5d1SWolfram Sang } 252282fe39a6SWolfram Sang EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf); 2523e94bc5d1SWolfram Sang 252491ed5349SWolfram Sang MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); 252591ed5349SWolfram Sang MODULE_DESCRIPTION("I2C-Bus main module"); 252691ed5349SWolfram Sang MODULE_LICENSE("GPL"); 2527