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 7991ed5349SWolfram Sang const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, 8091ed5349SWolfram Sang const struct i2c_client *client) 8191ed5349SWolfram Sang { 8291ed5349SWolfram Sang if (!(id && client)) 8391ed5349SWolfram Sang return NULL; 8491ed5349SWolfram Sang 8591ed5349SWolfram Sang while (id->name[0]) { 8691ed5349SWolfram Sang if (strcmp(client->name, id->name) == 0) 8791ed5349SWolfram Sang return id; 8891ed5349SWolfram Sang id++; 8991ed5349SWolfram Sang } 9091ed5349SWolfram Sang return NULL; 9191ed5349SWolfram Sang } 9291ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_match_id); 9391ed5349SWolfram Sang 9491ed5349SWolfram Sang static int i2c_device_match(struct device *dev, struct device_driver *drv) 9591ed5349SWolfram Sang { 9691ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 9791ed5349SWolfram Sang struct i2c_driver *driver; 9891ed5349SWolfram Sang 9991ed5349SWolfram Sang 10091ed5349SWolfram Sang /* Attempt an OF style match */ 10191ed5349SWolfram Sang if (i2c_of_match_device(drv->of_match_table, client)) 10291ed5349SWolfram Sang return 1; 10391ed5349SWolfram Sang 10491ed5349SWolfram Sang /* Then ACPI style match */ 10591ed5349SWolfram Sang if (acpi_driver_match_device(dev, drv)) 10691ed5349SWolfram Sang return 1; 10791ed5349SWolfram Sang 10891ed5349SWolfram Sang driver = to_i2c_driver(drv); 10991ed5349SWolfram Sang 11091ed5349SWolfram Sang /* Finally an I2C match */ 11191ed5349SWolfram Sang if (i2c_match_id(driver->id_table, client)) 11291ed5349SWolfram Sang return 1; 11391ed5349SWolfram Sang 11491ed5349SWolfram Sang return 0; 11591ed5349SWolfram Sang } 11691ed5349SWolfram Sang 11791ed5349SWolfram Sang static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) 11891ed5349SWolfram Sang { 11991ed5349SWolfram Sang struct i2c_client *client = to_i2c_client(dev); 12091ed5349SWolfram Sang int rc; 12191ed5349SWolfram Sang 122af503716SJavier Martinez Canillas rc = of_device_uevent_modalias(dev, env); 123af503716SJavier Martinez Canillas if (rc != -ENODEV) 124af503716SJavier Martinez Canillas return rc; 125af503716SJavier Martinez Canillas 12691ed5349SWolfram Sang rc = acpi_device_uevent_modalias(dev, env); 12791ed5349SWolfram Sang if (rc != -ENODEV) 12891ed5349SWolfram Sang return rc; 12991ed5349SWolfram Sang 13091ed5349SWolfram Sang return add_uevent_var(env, "MODALIAS=%s%s", I2C_MODULE_PREFIX, client->name); 13191ed5349SWolfram Sang } 13291ed5349SWolfram Sang 13391ed5349SWolfram Sang /* i2c bus recovery routines */ 13491ed5349SWolfram Sang static int get_scl_gpio_value(struct i2c_adapter *adap) 13591ed5349SWolfram Sang { 1363991c5c8SPhil Reid return gpiod_get_value_cansleep(adap->bus_recovery_info->scl_gpiod); 13791ed5349SWolfram Sang } 13891ed5349SWolfram Sang 13991ed5349SWolfram Sang static void set_scl_gpio_value(struct i2c_adapter *adap, int val) 14091ed5349SWolfram Sang { 1413991c5c8SPhil Reid gpiod_set_value_cansleep(adap->bus_recovery_info->scl_gpiod, val); 14291ed5349SWolfram Sang } 14391ed5349SWolfram Sang 14491ed5349SWolfram Sang static int get_sda_gpio_value(struct i2c_adapter *adap) 14591ed5349SWolfram Sang { 1463991c5c8SPhil Reid return gpiod_get_value_cansleep(adap->bus_recovery_info->sda_gpiod); 14791ed5349SWolfram Sang } 14891ed5349SWolfram Sang 1498092178fSWolfram Sang static void set_sda_gpio_value(struct i2c_adapter *adap, int val) 15091ed5349SWolfram Sang { 1518092178fSWolfram Sang gpiod_set_value_cansleep(adap->bus_recovery_info->sda_gpiod, val); 15291ed5349SWolfram Sang } 15391ed5349SWolfram Sang 1547ca5f6beSWolfram Sang static int i2c_generic_bus_free(struct i2c_adapter *adap) 1557ca5f6beSWolfram Sang { 1567ca5f6beSWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 1577ca5f6beSWolfram Sang int ret = -EOPNOTSUPP; 1587ca5f6beSWolfram Sang 1597ca5f6beSWolfram Sang if (bri->get_bus_free) 1607ca5f6beSWolfram Sang ret = bri->get_bus_free(adap); 1617ca5f6beSWolfram Sang else if (bri->get_sda) 1627ca5f6beSWolfram Sang ret = bri->get_sda(adap); 1637ca5f6beSWolfram Sang 1647ca5f6beSWolfram Sang if (ret < 0) 1657ca5f6beSWolfram Sang return ret; 1667ca5f6beSWolfram Sang 1677ca5f6beSWolfram Sang return ret ? 0 : -EBUSY; 1687ca5f6beSWolfram Sang } 1697ca5f6beSWolfram Sang 17091ed5349SWolfram Sang /* 17191ed5349SWolfram Sang * We are generating clock pulses. ndelay() determines durating of clk pulses. 17291ed5349SWolfram Sang * We will generate clock with rate 100 KHz and so duration of both clock levels 17391ed5349SWolfram Sang * is: delay in ns = (10^6 / 100) / 2 17491ed5349SWolfram Sang */ 17591ed5349SWolfram Sang #define RECOVERY_NDELAY 5000 17691ed5349SWolfram Sang #define RECOVERY_CLK_CNT 9 17791ed5349SWolfram Sang 178e1eb7d28SPhil Reid int i2c_generic_scl_recovery(struct i2c_adapter *adap) 17991ed5349SWolfram Sang { 18091ed5349SWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 181cf676908SLinus Torvalds int i = 0, scl = 1, ret = 0; 18291ed5349SWolfram Sang 18391ed5349SWolfram Sang if (bri->prepare_recovery) 18491ed5349SWolfram Sang bri->prepare_recovery(adap); 18575820314SCodrin Ciubotariu if (bri->pinctrl) 18675820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_gpio); 18791ed5349SWolfram Sang 188c4ae05b9SWolfram Sang /* 189c4ae05b9SWolfram Sang * If we can set SDA, we will always create a STOP to ensure additional 190c4ae05b9SWolfram Sang * pulses will do no harm. This is achieved by letting SDA follow SCL 191c4ae05b9SWolfram Sang * half a cycle later. Check the 'incomplete_write_byte' fault injector 192cf8ce8b8SRussell King * for details. Note that we must honour tsu:sto, 4us, but lets use 5us 193cf8ce8b8SRussell King * here for simplicity. 194c4ae05b9SWolfram Sang */ 195f7ff75e2SWolfram Sang bri->set_scl(adap, scl); 196cf8ce8b8SRussell King ndelay(RECOVERY_NDELAY); 19772b08fccSWolfram Sang if (bri->set_sda) 198c4ae05b9SWolfram Sang bri->set_sda(adap, scl); 199c4ae05b9SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 20091ed5349SWolfram Sang 20191ed5349SWolfram Sang /* 20291ed5349SWolfram Sang * By this time SCL is high, as we need to give 9 falling-rising edges 20391ed5349SWolfram Sang */ 20491ed5349SWolfram Sang while (i++ < RECOVERY_CLK_CNT * 2) { 205f7ff75e2SWolfram Sang if (scl) { 20691ed5349SWolfram Sang /* SCL shouldn't be low here */ 20791ed5349SWolfram Sang if (!bri->get_scl(adap)) { 20891ed5349SWolfram Sang dev_err(&adap->dev, 20991ed5349SWolfram Sang "SCL is stuck low, exit recovery\n"); 21091ed5349SWolfram Sang ret = -EBUSY; 21191ed5349SWolfram Sang break; 21291ed5349SWolfram Sang } 21391ed5349SWolfram Sang } 21491ed5349SWolfram Sang 215f7ff75e2SWolfram Sang scl = !scl; 216f7ff75e2SWolfram Sang bri->set_scl(adap, scl); 217c4ae05b9SWolfram Sang /* Creating STOP again, see above */ 218cf8ce8b8SRussell King if (scl) { 219cf8ce8b8SRussell King /* Honour minimum tsu:sto */ 220cf8ce8b8SRussell King ndelay(RECOVERY_NDELAY); 221cf8ce8b8SRussell King } else { 222cf8ce8b8SRussell King /* Honour minimum tf and thd:dat */ 223abe41184SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 224cf8ce8b8SRussell King } 225abe41184SWolfram Sang if (bri->set_sda) 226f7ff75e2SWolfram Sang bri->set_sda(adap, scl); 227abe41184SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 2280b71026cSWolfram Sang 229f7ff75e2SWolfram Sang if (scl) { 2307ca5f6beSWolfram Sang ret = i2c_generic_bus_free(adap); 2310b71026cSWolfram Sang if (ret == 0) 2320b71026cSWolfram Sang break; 23391ed5349SWolfram Sang } 23491ed5349SWolfram Sang } 23591ed5349SWolfram Sang 2367ca5f6beSWolfram Sang /* If we can't check bus status, assume recovery worked */ 2377ca5f6beSWolfram Sang if (ret == -EOPNOTSUPP) 2387ca5f6beSWolfram Sang ret = 0; 2392806e6adSWolfram Sang 24091ed5349SWolfram Sang if (bri->unprepare_recovery) 24191ed5349SWolfram Sang bri->unprepare_recovery(adap); 24275820314SCodrin Ciubotariu if (bri->pinctrl) 24375820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_default); 24491ed5349SWolfram Sang 24591ed5349SWolfram Sang return ret; 24691ed5349SWolfram Sang } 24791ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); 24891ed5349SWolfram Sang 24991ed5349SWolfram Sang int i2c_recover_bus(struct i2c_adapter *adap) 25091ed5349SWolfram Sang { 25191ed5349SWolfram Sang if (!adap->bus_recovery_info) 25291ed5349SWolfram Sang return -EOPNOTSUPP; 25391ed5349SWolfram Sang 25491ed5349SWolfram Sang dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); 25591ed5349SWolfram Sang return adap->bus_recovery_info->recover_bus(adap); 25691ed5349SWolfram Sang } 25791ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_recover_bus); 25891ed5349SWolfram Sang 25975820314SCodrin Ciubotariu static void i2c_gpio_init_pinctrl_recovery(struct i2c_adapter *adap) 26075820314SCodrin Ciubotariu { 26175820314SCodrin Ciubotariu struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 26275820314SCodrin Ciubotariu struct device *dev = &adap->dev; 26375820314SCodrin Ciubotariu struct pinctrl *p = bri->pinctrl; 26475820314SCodrin Ciubotariu 26575820314SCodrin Ciubotariu /* 26675820314SCodrin Ciubotariu * we can't change states without pinctrl, so remove the states if 26775820314SCodrin Ciubotariu * populated 26875820314SCodrin Ciubotariu */ 26975820314SCodrin Ciubotariu if (!p) { 27075820314SCodrin Ciubotariu bri->pins_default = NULL; 27175820314SCodrin Ciubotariu bri->pins_gpio = NULL; 27275820314SCodrin Ciubotariu return; 27375820314SCodrin Ciubotariu } 27475820314SCodrin Ciubotariu 27575820314SCodrin Ciubotariu if (!bri->pins_default) { 27675820314SCodrin Ciubotariu bri->pins_default = pinctrl_lookup_state(p, 27775820314SCodrin Ciubotariu PINCTRL_STATE_DEFAULT); 27875820314SCodrin Ciubotariu if (IS_ERR(bri->pins_default)) { 27975820314SCodrin Ciubotariu dev_dbg(dev, PINCTRL_STATE_DEFAULT " state not found for GPIO recovery\n"); 28075820314SCodrin Ciubotariu bri->pins_default = NULL; 28175820314SCodrin Ciubotariu } 28275820314SCodrin Ciubotariu } 28375820314SCodrin Ciubotariu if (!bri->pins_gpio) { 28475820314SCodrin Ciubotariu bri->pins_gpio = pinctrl_lookup_state(p, "gpio"); 28575820314SCodrin Ciubotariu if (IS_ERR(bri->pins_gpio)) 28675820314SCodrin Ciubotariu bri->pins_gpio = pinctrl_lookup_state(p, "recovery"); 28775820314SCodrin Ciubotariu 28875820314SCodrin Ciubotariu if (IS_ERR(bri->pins_gpio)) { 28975820314SCodrin Ciubotariu dev_dbg(dev, "no gpio or recovery state found for GPIO recovery\n"); 29075820314SCodrin Ciubotariu bri->pins_gpio = NULL; 29175820314SCodrin Ciubotariu } 29275820314SCodrin Ciubotariu } 29375820314SCodrin Ciubotariu 29475820314SCodrin Ciubotariu /* for pinctrl state changes, we need all the information */ 29575820314SCodrin Ciubotariu if (bri->pins_default && bri->pins_gpio) { 29675820314SCodrin Ciubotariu dev_info(dev, "using pinctrl states for GPIO recovery"); 29775820314SCodrin Ciubotariu } else { 29875820314SCodrin Ciubotariu bri->pinctrl = NULL; 29975820314SCodrin Ciubotariu bri->pins_default = NULL; 30075820314SCodrin Ciubotariu bri->pins_gpio = NULL; 30175820314SCodrin Ciubotariu } 30275820314SCodrin Ciubotariu } 30375820314SCodrin Ciubotariu 30475820314SCodrin Ciubotariu static int i2c_gpio_init_generic_recovery(struct i2c_adapter *adap) 30575820314SCodrin Ciubotariu { 30675820314SCodrin Ciubotariu struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 30775820314SCodrin Ciubotariu struct device *dev = &adap->dev; 30875820314SCodrin Ciubotariu struct gpio_desc *gpiod; 30975820314SCodrin Ciubotariu int ret = 0; 31075820314SCodrin Ciubotariu 31175820314SCodrin Ciubotariu /* 31275820314SCodrin Ciubotariu * don't touch the recovery information if the driver is not using 31375820314SCodrin Ciubotariu * generic SCL recovery 31475820314SCodrin Ciubotariu */ 31575820314SCodrin Ciubotariu if (bri->recover_bus && bri->recover_bus != i2c_generic_scl_recovery) 31675820314SCodrin Ciubotariu return 0; 31775820314SCodrin Ciubotariu 31875820314SCodrin Ciubotariu /* 31975820314SCodrin Ciubotariu * pins might be taken as GPIO, so we should inform pinctrl about 32075820314SCodrin Ciubotariu * this and move the state to GPIO 32175820314SCodrin Ciubotariu */ 32275820314SCodrin Ciubotariu if (bri->pinctrl) 32375820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_gpio); 32475820314SCodrin Ciubotariu 32575820314SCodrin Ciubotariu /* 32675820314SCodrin Ciubotariu * if there is incomplete or no recovery information, see if generic 32775820314SCodrin Ciubotariu * GPIO recovery is available 32875820314SCodrin Ciubotariu */ 32975820314SCodrin Ciubotariu if (!bri->scl_gpiod) { 33075820314SCodrin Ciubotariu gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); 33175820314SCodrin Ciubotariu if (PTR_ERR(gpiod) == -EPROBE_DEFER) { 33275820314SCodrin Ciubotariu ret = -EPROBE_DEFER; 33375820314SCodrin Ciubotariu goto cleanup_pinctrl_state; 33475820314SCodrin Ciubotariu } 33575820314SCodrin Ciubotariu if (!IS_ERR(gpiod)) { 33675820314SCodrin Ciubotariu bri->scl_gpiod = gpiod; 33775820314SCodrin Ciubotariu bri->recover_bus = i2c_generic_scl_recovery; 33875820314SCodrin Ciubotariu dev_info(dev, "using generic GPIOs for recovery\n"); 33975820314SCodrin Ciubotariu } 34075820314SCodrin Ciubotariu } 34175820314SCodrin Ciubotariu 34275820314SCodrin Ciubotariu /* SDA GPIOD line is optional, so we care about DEFER only */ 34375820314SCodrin Ciubotariu if (!bri->sda_gpiod) { 34475820314SCodrin Ciubotariu /* 34575820314SCodrin Ciubotariu * We have SCL. Pull SCL low and wait a bit so that SDA glitches 34675820314SCodrin Ciubotariu * have no effect. 34775820314SCodrin Ciubotariu */ 34875820314SCodrin Ciubotariu gpiod_direction_output(bri->scl_gpiod, 0); 34975820314SCodrin Ciubotariu udelay(10); 35075820314SCodrin Ciubotariu gpiod = devm_gpiod_get(dev, "sda", GPIOD_IN); 35175820314SCodrin Ciubotariu 35275820314SCodrin Ciubotariu /* Wait a bit in case of a SDA glitch, and then release SCL. */ 35375820314SCodrin Ciubotariu udelay(10); 35475820314SCodrin Ciubotariu gpiod_direction_output(bri->scl_gpiod, 1); 35575820314SCodrin Ciubotariu 35675820314SCodrin Ciubotariu if (PTR_ERR(gpiod) == -EPROBE_DEFER) { 35775820314SCodrin Ciubotariu ret = -EPROBE_DEFER; 35875820314SCodrin Ciubotariu goto cleanup_pinctrl_state; 35975820314SCodrin Ciubotariu } 36075820314SCodrin Ciubotariu if (!IS_ERR(gpiod)) 36175820314SCodrin Ciubotariu bri->sda_gpiod = gpiod; 36275820314SCodrin Ciubotariu } 36375820314SCodrin Ciubotariu 36475820314SCodrin Ciubotariu cleanup_pinctrl_state: 36575820314SCodrin Ciubotariu /* change the state of the pins back to their default state */ 36675820314SCodrin Ciubotariu if (bri->pinctrl) 36775820314SCodrin Ciubotariu pinctrl_select_state(bri->pinctrl, bri->pins_default); 36875820314SCodrin Ciubotariu 36975820314SCodrin Ciubotariu return ret; 37075820314SCodrin Ciubotariu } 37175820314SCodrin Ciubotariu 37275820314SCodrin Ciubotariu static int i2c_gpio_init_recovery(struct i2c_adapter *adap) 37375820314SCodrin Ciubotariu { 37475820314SCodrin Ciubotariu i2c_gpio_init_pinctrl_recovery(adap); 37575820314SCodrin Ciubotariu return i2c_gpio_init_generic_recovery(adap); 37675820314SCodrin Ciubotariu } 37775820314SCodrin Ciubotariu 37823a698feSCodrin Ciubotariu static int i2c_init_recovery(struct i2c_adapter *adap) 37991ed5349SWolfram Sang { 38091ed5349SWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 38191ed5349SWolfram Sang char *err_str; 38291ed5349SWolfram Sang 38391ed5349SWolfram Sang if (!bri) 38423a698feSCodrin Ciubotariu return 0; 38591ed5349SWolfram Sang 38623a698feSCodrin Ciubotariu if (i2c_gpio_init_recovery(adap) == -EPROBE_DEFER) 38723a698feSCodrin Ciubotariu return -EPROBE_DEFER; 38875820314SCodrin Ciubotariu 38991ed5349SWolfram Sang if (!bri->recover_bus) { 39091ed5349SWolfram Sang err_str = "no recover_bus() found"; 39191ed5349SWolfram Sang goto err; 39291ed5349SWolfram Sang } 39391ed5349SWolfram Sang 3943991c5c8SPhil Reid if (bri->scl_gpiod && bri->recover_bus == i2c_generic_scl_recovery) { 39591ed5349SWolfram Sang bri->get_scl = get_scl_gpio_value; 39691ed5349SWolfram Sang bri->set_scl = set_scl_gpio_value; 3978092178fSWolfram Sang if (bri->sda_gpiod) { 3983991c5c8SPhil Reid bri->get_sda = get_sda_gpio_value; 3998092178fSWolfram Sang /* FIXME: add proper flag instead of '0' once available */ 4008092178fSWolfram Sang if (gpiod_get_direction(bri->sda_gpiod) == 0) 4018092178fSWolfram Sang bri->set_sda = set_sda_gpio_value; 4028092178fSWolfram Sang } 40323a698feSCodrin Ciubotariu } else if (bri->recover_bus == i2c_generic_scl_recovery) { 40491ed5349SWolfram Sang /* Generic SCL recovery */ 40591ed5349SWolfram Sang if (!bri->set_scl || !bri->get_scl) { 40691ed5349SWolfram Sang err_str = "no {get|set}_scl() found"; 40791ed5349SWolfram Sang goto err; 40891ed5349SWolfram Sang } 409ffc59c49SWolfram Sang if (!bri->set_sda && !bri->get_sda) { 410ffc59c49SWolfram Sang err_str = "either get_sda() or set_sda() needed"; 411ffc59c49SWolfram Sang goto err; 412ffc59c49SWolfram Sang } 41391ed5349SWolfram Sang } 41491ed5349SWolfram Sang 41523a698feSCodrin Ciubotariu return 0; 41691ed5349SWolfram Sang err: 41791ed5349SWolfram Sang dev_err(&adap->dev, "Not using recovery: %s\n", err_str); 41891ed5349SWolfram Sang adap->bus_recovery_info = NULL; 41923a698feSCodrin Ciubotariu 42023a698feSCodrin Ciubotariu return -EINVAL; 42191ed5349SWolfram Sang } 42291ed5349SWolfram Sang 42391ed5349SWolfram Sang static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) 42491ed5349SWolfram Sang { 42591ed5349SWolfram Sang struct i2c_adapter *adap = client->adapter; 42691ed5349SWolfram Sang unsigned int irq; 42791ed5349SWolfram Sang 42891ed5349SWolfram Sang if (!adap->host_notify_domain) 42991ed5349SWolfram Sang return -ENXIO; 43091ed5349SWolfram Sang 43191ed5349SWolfram Sang if (client->flags & I2C_CLIENT_TEN) 43291ed5349SWolfram Sang return -EINVAL; 43391ed5349SWolfram Sang 434b9bb3fdfSCharles Keepax irq = irq_create_mapping(adap->host_notify_domain, client->addr); 43591ed5349SWolfram Sang 43691ed5349SWolfram Sang return irq > 0 ? irq : -ENXIO; 43791ed5349SWolfram Sang } 43891ed5349SWolfram Sang 43991ed5349SWolfram Sang static int i2c_device_probe(struct device *dev) 44091ed5349SWolfram Sang { 44191ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 44291ed5349SWolfram Sang struct i2c_driver *driver; 44391ed5349SWolfram Sang int status; 44491ed5349SWolfram Sang 44591ed5349SWolfram Sang if (!client) 44691ed5349SWolfram Sang return 0; 44791ed5349SWolfram Sang 4486e76cb7dSCharles Keepax client->irq = client->init_irq; 4496e76cb7dSCharles Keepax 4500c2a3493SWolfram Sang if (!client->irq) { 45191ed5349SWolfram Sang int irq = -ENOENT; 45291ed5349SWolfram Sang 45391ed5349SWolfram Sang if (client->flags & I2C_CLIENT_HOST_NOTIFY) { 45491ed5349SWolfram Sang dev_dbg(dev, "Using Host Notify IRQ\n"); 45572bfcee1SJarkko Nikula /* Keep adapter active when Host Notify is required */ 45672bfcee1SJarkko Nikula pm_runtime_get_sync(&client->adapter->dev); 45791ed5349SWolfram Sang irq = i2c_smbus_host_notify_to_irq(client); 45891ed5349SWolfram Sang } else if (dev->of_node) { 45991ed5349SWolfram Sang irq = of_irq_get_byname(dev->of_node, "irq"); 46091ed5349SWolfram Sang if (irq == -EINVAL || irq == -ENODATA) 46191ed5349SWolfram Sang irq = of_irq_get(dev->of_node, 0); 46291ed5349SWolfram Sang } else if (ACPI_COMPANION(dev)) { 46316c9db1dSCharles Keepax irq = i2c_acpi_get_irq(client); 46491ed5349SWolfram Sang } 4653c3dd56fSAlain Volmat if (irq == -EPROBE_DEFER) { 4663c3dd56fSAlain Volmat status = irq; 4673c3dd56fSAlain Volmat goto put_sync_adapter; 4683c3dd56fSAlain Volmat } 46991ed5349SWolfram Sang 47091ed5349SWolfram Sang if (irq < 0) 47191ed5349SWolfram Sang irq = 0; 47291ed5349SWolfram Sang 47391ed5349SWolfram Sang client->irq = irq; 47491ed5349SWolfram Sang } 47591ed5349SWolfram Sang 4760c2a3493SWolfram Sang driver = to_i2c_driver(dev->driver); 4770c2a3493SWolfram Sang 47891ed5349SWolfram Sang /* 479f4b17a14SJavier Martinez Canillas * An I2C ID table is not mandatory, if and only if, a suitable OF 480f4b17a14SJavier Martinez Canillas * or ACPI ID table is supplied for the probing device. 48191ed5349SWolfram Sang */ 48291ed5349SWolfram Sang if (!driver->id_table && 483e3cb82c6SAndy Shevchenko !acpi_driver_match_device(dev, dev->driver) && 4843c3dd56fSAlain Volmat !i2c_of_match_device(dev->driver->of_match_table, client)) { 4853c3dd56fSAlain Volmat status = -ENODEV; 4863c3dd56fSAlain Volmat goto put_sync_adapter; 4873c3dd56fSAlain Volmat } 48891ed5349SWolfram Sang 48991ed5349SWolfram Sang if (client->flags & I2C_CLIENT_WAKE) { 4903e99834cSAndy Shevchenko int wakeirq; 49191ed5349SWolfram Sang 49291ed5349SWolfram Sang wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); 4933c3dd56fSAlain Volmat if (wakeirq == -EPROBE_DEFER) { 4943c3dd56fSAlain Volmat status = wakeirq; 4953c3dd56fSAlain Volmat goto put_sync_adapter; 4963c3dd56fSAlain Volmat } 49791ed5349SWolfram Sang 49891ed5349SWolfram Sang device_init_wakeup(&client->dev, true); 49991ed5349SWolfram Sang 50091ed5349SWolfram Sang if (wakeirq > 0 && wakeirq != client->irq) 50191ed5349SWolfram Sang status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); 50291ed5349SWolfram Sang else if (client->irq > 0) 50391ed5349SWolfram Sang status = dev_pm_set_wake_irq(dev, client->irq); 50491ed5349SWolfram Sang else 50591ed5349SWolfram Sang status = 0; 50691ed5349SWolfram Sang 50791ed5349SWolfram Sang if (status) 50891ed5349SWolfram Sang dev_warn(&client->dev, "failed to set up wakeup irq\n"); 50991ed5349SWolfram Sang } 51091ed5349SWolfram Sang 51191ed5349SWolfram Sang dev_dbg(dev, "probe\n"); 51291ed5349SWolfram Sang 51391ed5349SWolfram Sang status = of_clk_set_defaults(dev->of_node, false); 51491ed5349SWolfram Sang if (status < 0) 51591ed5349SWolfram Sang goto err_clear_wakeup_irq; 51691ed5349SWolfram Sang 51791ed5349SWolfram Sang status = dev_pm_domain_attach(&client->dev, true); 518e6a20b6cSUlf Hansson if (status) 51991ed5349SWolfram Sang goto err_clear_wakeup_irq; 52091ed5349SWolfram Sang 52191ed5349SWolfram Sang /* 52291ed5349SWolfram Sang * When there are no more users of probe(), 52391ed5349SWolfram Sang * rename probe_new to probe. 52491ed5349SWolfram Sang */ 52591ed5349SWolfram Sang if (driver->probe_new) 52691ed5349SWolfram Sang status = driver->probe_new(client); 52791ed5349SWolfram Sang else if (driver->probe) 52891ed5349SWolfram Sang status = driver->probe(client, 52991ed5349SWolfram Sang i2c_match_id(driver->id_table, client)); 53091ed5349SWolfram Sang else 53191ed5349SWolfram Sang status = -EINVAL; 53291ed5349SWolfram Sang 53391ed5349SWolfram Sang if (status) 53491ed5349SWolfram Sang goto err_detach_pm_domain; 53591ed5349SWolfram Sang 53691ed5349SWolfram Sang return 0; 53791ed5349SWolfram Sang 53891ed5349SWolfram Sang err_detach_pm_domain: 53991ed5349SWolfram Sang dev_pm_domain_detach(&client->dev, true); 54091ed5349SWolfram Sang err_clear_wakeup_irq: 54191ed5349SWolfram Sang dev_pm_clear_wake_irq(&client->dev); 54291ed5349SWolfram Sang device_init_wakeup(&client->dev, false); 5433c3dd56fSAlain Volmat put_sync_adapter: 5443c3dd56fSAlain Volmat if (client->flags & I2C_CLIENT_HOST_NOTIFY) 5453c3dd56fSAlain Volmat pm_runtime_put_sync(&client->adapter->dev); 5463c3dd56fSAlain Volmat 54791ed5349SWolfram Sang return status; 54891ed5349SWolfram Sang } 54991ed5349SWolfram Sang 55091ed5349SWolfram Sang static int i2c_device_remove(struct device *dev) 55191ed5349SWolfram Sang { 55291ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 55391ed5349SWolfram Sang struct i2c_driver *driver; 55491ed5349SWolfram Sang int status = 0; 55591ed5349SWolfram Sang 55691ed5349SWolfram Sang if (!client || !dev->driver) 55791ed5349SWolfram Sang return 0; 55891ed5349SWolfram Sang 55991ed5349SWolfram Sang driver = to_i2c_driver(dev->driver); 56091ed5349SWolfram Sang if (driver->remove) { 56191ed5349SWolfram Sang dev_dbg(dev, "remove\n"); 56291ed5349SWolfram Sang status = driver->remove(client); 56391ed5349SWolfram Sang } 56491ed5349SWolfram Sang 56591ed5349SWolfram Sang dev_pm_domain_detach(&client->dev, true); 56691ed5349SWolfram Sang 56791ed5349SWolfram Sang dev_pm_clear_wake_irq(&client->dev); 56891ed5349SWolfram Sang device_init_wakeup(&client->dev, false); 56991ed5349SWolfram Sang 5706e76cb7dSCharles Keepax client->irq = 0; 57172bfcee1SJarkko Nikula if (client->flags & I2C_CLIENT_HOST_NOTIFY) 57272bfcee1SJarkko Nikula pm_runtime_put(&client->adapter->dev); 5736f108dd7SCharles Keepax 57491ed5349SWolfram Sang return status; 57591ed5349SWolfram Sang } 57691ed5349SWolfram Sang 57791ed5349SWolfram Sang static void i2c_device_shutdown(struct device *dev) 57891ed5349SWolfram Sang { 57991ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 58091ed5349SWolfram Sang struct i2c_driver *driver; 58191ed5349SWolfram Sang 58291ed5349SWolfram Sang if (!client || !dev->driver) 58391ed5349SWolfram Sang return; 58491ed5349SWolfram Sang driver = to_i2c_driver(dev->driver); 58591ed5349SWolfram Sang if (driver->shutdown) 58691ed5349SWolfram Sang driver->shutdown(client); 58791ed5349SWolfram Sang } 58891ed5349SWolfram Sang 58991ed5349SWolfram Sang static void i2c_client_dev_release(struct device *dev) 59091ed5349SWolfram Sang { 59191ed5349SWolfram Sang kfree(to_i2c_client(dev)); 59291ed5349SWolfram Sang } 59391ed5349SWolfram Sang 59491ed5349SWolfram Sang static ssize_t 59554a19fd4SGeert Uytterhoeven name_show(struct device *dev, struct device_attribute *attr, char *buf) 59691ed5349SWolfram Sang { 59791ed5349SWolfram Sang return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? 59891ed5349SWolfram Sang to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); 59991ed5349SWolfram Sang } 60054a19fd4SGeert Uytterhoeven static DEVICE_ATTR_RO(name); 60191ed5349SWolfram Sang 60291ed5349SWolfram Sang static ssize_t 60354a19fd4SGeert Uytterhoeven modalias_show(struct device *dev, struct device_attribute *attr, char *buf) 60491ed5349SWolfram Sang { 60591ed5349SWolfram Sang struct i2c_client *client = to_i2c_client(dev); 60691ed5349SWolfram Sang int len; 60791ed5349SWolfram Sang 608af503716SJavier Martinez Canillas len = of_device_modalias(dev, buf, PAGE_SIZE); 609af503716SJavier Martinez Canillas if (len != -ENODEV) 610af503716SJavier Martinez Canillas return len; 611af503716SJavier Martinez Canillas 61291ed5349SWolfram Sang len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); 61391ed5349SWolfram Sang if (len != -ENODEV) 61491ed5349SWolfram Sang return len; 61591ed5349SWolfram Sang 61691ed5349SWolfram Sang return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); 61791ed5349SWolfram Sang } 61854a19fd4SGeert Uytterhoeven static DEVICE_ATTR_RO(modalias); 61991ed5349SWolfram Sang 62091ed5349SWolfram Sang static struct attribute *i2c_dev_attrs[] = { 62191ed5349SWolfram Sang &dev_attr_name.attr, 62291ed5349SWolfram Sang /* modalias helps coldplug: modprobe $(cat .../modalias) */ 62391ed5349SWolfram Sang &dev_attr_modalias.attr, 62491ed5349SWolfram Sang NULL 62591ed5349SWolfram Sang }; 62691ed5349SWolfram Sang ATTRIBUTE_GROUPS(i2c_dev); 62791ed5349SWolfram Sang 62891ed5349SWolfram Sang struct bus_type i2c_bus_type = { 62991ed5349SWolfram Sang .name = "i2c", 63091ed5349SWolfram Sang .match = i2c_device_match, 63191ed5349SWolfram Sang .probe = i2c_device_probe, 63291ed5349SWolfram Sang .remove = i2c_device_remove, 63391ed5349SWolfram Sang .shutdown = i2c_device_shutdown, 63491ed5349SWolfram Sang }; 63591ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_bus_type); 63691ed5349SWolfram Sang 63791ed5349SWolfram Sang struct device_type i2c_client_type = { 63891ed5349SWolfram Sang .groups = i2c_dev_groups, 63991ed5349SWolfram Sang .uevent = i2c_device_uevent, 64091ed5349SWolfram Sang .release = i2c_client_dev_release, 64191ed5349SWolfram Sang }; 64291ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_client_type); 64391ed5349SWolfram Sang 64491ed5349SWolfram Sang 64591ed5349SWolfram Sang /** 64691ed5349SWolfram Sang * i2c_verify_client - return parameter as i2c_client, or NULL 64791ed5349SWolfram Sang * @dev: device, probably from some driver model iterator 64891ed5349SWolfram Sang * 64991ed5349SWolfram Sang * When traversing the driver model tree, perhaps using driver model 65091ed5349SWolfram Sang * iterators like @device_for_each_child(), you can't assume very much 65191ed5349SWolfram Sang * about the nodes you find. Use this function to avoid oopses caused 65291ed5349SWolfram Sang * by wrongly treating some non-I2C device as an i2c_client. 65391ed5349SWolfram Sang */ 65491ed5349SWolfram Sang struct i2c_client *i2c_verify_client(struct device *dev) 65591ed5349SWolfram Sang { 65691ed5349SWolfram Sang return (dev->type == &i2c_client_type) 65791ed5349SWolfram Sang ? to_i2c_client(dev) 65891ed5349SWolfram Sang : NULL; 65991ed5349SWolfram Sang } 66091ed5349SWolfram Sang EXPORT_SYMBOL(i2c_verify_client); 66191ed5349SWolfram Sang 66291ed5349SWolfram Sang 66391ed5349SWolfram Sang /* Return a unique address which takes the flags of the client into account */ 66491ed5349SWolfram Sang static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) 66591ed5349SWolfram Sang { 66691ed5349SWolfram Sang unsigned short addr = client->addr; 66791ed5349SWolfram Sang 66891ed5349SWolfram Sang /* For some client flags, add an arbitrary offset to avoid collisions */ 66991ed5349SWolfram Sang if (client->flags & I2C_CLIENT_TEN) 67091ed5349SWolfram Sang addr |= I2C_ADDR_OFFSET_TEN_BIT; 67191ed5349SWolfram Sang 67291ed5349SWolfram Sang if (client->flags & I2C_CLIENT_SLAVE) 67391ed5349SWolfram Sang addr |= I2C_ADDR_OFFSET_SLAVE; 67491ed5349SWolfram Sang 67591ed5349SWolfram Sang return addr; 67691ed5349SWolfram Sang } 67791ed5349SWolfram Sang 67891ed5349SWolfram Sang /* This is a permissive address validity check, I2C address map constraints 67991ed5349SWolfram Sang * are purposely not enforced, except for the general call address. */ 680398432edSWolfram Sang static int i2c_check_addr_validity(unsigned int addr, unsigned short flags) 68191ed5349SWolfram Sang { 68291ed5349SWolfram Sang if (flags & I2C_CLIENT_TEN) { 68391ed5349SWolfram Sang /* 10-bit address, all values are valid */ 68491ed5349SWolfram Sang if (addr > 0x3ff) 68591ed5349SWolfram Sang return -EINVAL; 68691ed5349SWolfram Sang } else { 68791ed5349SWolfram Sang /* 7-bit address, reject the general call address */ 68891ed5349SWolfram Sang if (addr == 0x00 || addr > 0x7f) 68991ed5349SWolfram Sang return -EINVAL; 69091ed5349SWolfram Sang } 69191ed5349SWolfram Sang return 0; 69291ed5349SWolfram Sang } 69391ed5349SWolfram Sang 69491ed5349SWolfram Sang /* And this is a strict address validity check, used when probing. If a 69591ed5349SWolfram Sang * device uses a reserved address, then it shouldn't be probed. 7-bit 69691ed5349SWolfram Sang * addressing is assumed, 10-bit address devices are rare and should be 69791ed5349SWolfram Sang * explicitly enumerated. */ 698e4991ecdSWolfram Sang int i2c_check_7bit_addr_validity_strict(unsigned short addr) 69991ed5349SWolfram Sang { 70091ed5349SWolfram Sang /* 70191ed5349SWolfram Sang * Reserved addresses per I2C specification: 70291ed5349SWolfram Sang * 0x00 General call address / START byte 70391ed5349SWolfram Sang * 0x01 CBUS address 70491ed5349SWolfram Sang * 0x02 Reserved for different bus format 70591ed5349SWolfram Sang * 0x03 Reserved for future purposes 70691ed5349SWolfram Sang * 0x04-0x07 Hs-mode master code 70791ed5349SWolfram Sang * 0x78-0x7b 10-bit slave addressing 70891ed5349SWolfram Sang * 0x7c-0x7f Reserved for future purposes 70991ed5349SWolfram Sang */ 71091ed5349SWolfram Sang if (addr < 0x08 || addr > 0x77) 71191ed5349SWolfram Sang return -EINVAL; 71291ed5349SWolfram Sang return 0; 71391ed5349SWolfram Sang } 71491ed5349SWolfram Sang 71591ed5349SWolfram Sang static int __i2c_check_addr_busy(struct device *dev, void *addrp) 71691ed5349SWolfram Sang { 71791ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 71891ed5349SWolfram Sang int addr = *(int *)addrp; 71991ed5349SWolfram Sang 72091ed5349SWolfram Sang if (client && i2c_encode_flags_to_addr(client) == addr) 72191ed5349SWolfram Sang return -EBUSY; 72291ed5349SWolfram Sang return 0; 72391ed5349SWolfram Sang } 72491ed5349SWolfram Sang 72591ed5349SWolfram Sang /* walk up mux tree */ 72691ed5349SWolfram Sang static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) 72791ed5349SWolfram Sang { 72891ed5349SWolfram Sang struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); 72991ed5349SWolfram Sang int result; 73091ed5349SWolfram Sang 73191ed5349SWolfram Sang result = device_for_each_child(&adapter->dev, &addr, 73291ed5349SWolfram Sang __i2c_check_addr_busy); 73391ed5349SWolfram Sang 73491ed5349SWolfram Sang if (!result && parent) 73591ed5349SWolfram Sang result = i2c_check_mux_parents(parent, addr); 73691ed5349SWolfram Sang 73791ed5349SWolfram Sang return result; 73891ed5349SWolfram Sang } 73991ed5349SWolfram Sang 74091ed5349SWolfram Sang /* recurse down mux tree */ 74191ed5349SWolfram Sang static int i2c_check_mux_children(struct device *dev, void *addrp) 74291ed5349SWolfram Sang { 74391ed5349SWolfram Sang int result; 74491ed5349SWolfram Sang 74591ed5349SWolfram Sang if (dev->type == &i2c_adapter_type) 74691ed5349SWolfram Sang result = device_for_each_child(dev, addrp, 74791ed5349SWolfram Sang i2c_check_mux_children); 74891ed5349SWolfram Sang else 74991ed5349SWolfram Sang result = __i2c_check_addr_busy(dev, addrp); 75091ed5349SWolfram Sang 75191ed5349SWolfram Sang return result; 75291ed5349SWolfram Sang } 75391ed5349SWolfram Sang 75491ed5349SWolfram Sang static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) 75591ed5349SWolfram Sang { 75691ed5349SWolfram Sang struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); 75791ed5349SWolfram Sang int result = 0; 75891ed5349SWolfram Sang 75991ed5349SWolfram Sang if (parent) 76091ed5349SWolfram Sang result = i2c_check_mux_parents(parent, addr); 76191ed5349SWolfram Sang 76291ed5349SWolfram Sang if (!result) 76391ed5349SWolfram Sang result = device_for_each_child(&adapter->dev, &addr, 76491ed5349SWolfram Sang i2c_check_mux_children); 76591ed5349SWolfram Sang 76691ed5349SWolfram Sang return result; 76791ed5349SWolfram Sang } 76891ed5349SWolfram Sang 76991ed5349SWolfram Sang /** 77091ed5349SWolfram Sang * i2c_adapter_lock_bus - Get exclusive access to an I2C bus segment 77191ed5349SWolfram Sang * @adapter: Target I2C bus segment 77291ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT 77391ed5349SWolfram Sang * locks only this branch in the adapter tree 77491ed5349SWolfram Sang */ 77591ed5349SWolfram Sang static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, 77691ed5349SWolfram Sang unsigned int flags) 77791ed5349SWolfram Sang { 7787b94ea50SPeter Rosin rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter)); 77991ed5349SWolfram Sang } 78091ed5349SWolfram Sang 78191ed5349SWolfram Sang /** 78291ed5349SWolfram Sang * i2c_adapter_trylock_bus - Try to get exclusive access to an I2C bus segment 78391ed5349SWolfram Sang * @adapter: Target I2C bus segment 78491ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER trylocks the root i2c adapter, I2C_LOCK_SEGMENT 78591ed5349SWolfram Sang * trylocks only this branch in the adapter tree 78691ed5349SWolfram Sang */ 78791ed5349SWolfram Sang static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, 78891ed5349SWolfram Sang unsigned int flags) 78991ed5349SWolfram Sang { 79091ed5349SWolfram Sang return rt_mutex_trylock(&adapter->bus_lock); 79191ed5349SWolfram Sang } 79291ed5349SWolfram Sang 79391ed5349SWolfram Sang /** 79491ed5349SWolfram Sang * i2c_adapter_unlock_bus - Release exclusive access to an I2C bus segment 79591ed5349SWolfram Sang * @adapter: Target I2C bus segment 79691ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT 79791ed5349SWolfram Sang * unlocks only this branch in the adapter tree 79891ed5349SWolfram Sang */ 79991ed5349SWolfram Sang static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, 80091ed5349SWolfram Sang unsigned int flags) 80191ed5349SWolfram Sang { 80291ed5349SWolfram Sang rt_mutex_unlock(&adapter->bus_lock); 80391ed5349SWolfram Sang } 80491ed5349SWolfram Sang 80591ed5349SWolfram Sang static void i2c_dev_set_name(struct i2c_adapter *adap, 806728fe6ceSHans de Goede struct i2c_client *client, 807728fe6ceSHans de Goede struct i2c_board_info const *info) 80891ed5349SWolfram Sang { 80991ed5349SWolfram Sang struct acpi_device *adev = ACPI_COMPANION(&client->dev); 81091ed5349SWolfram Sang 811728fe6ceSHans de Goede if (info && info->dev_name) { 812728fe6ceSHans de Goede dev_set_name(&client->dev, "i2c-%s", info->dev_name); 813728fe6ceSHans de Goede return; 814728fe6ceSHans de Goede } 815728fe6ceSHans de Goede 81691ed5349SWolfram Sang if (adev) { 81791ed5349SWolfram Sang dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); 81891ed5349SWolfram Sang return; 81991ed5349SWolfram Sang } 82091ed5349SWolfram Sang 82191ed5349SWolfram Sang dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), 82291ed5349SWolfram Sang i2c_encode_flags_to_addr(client)); 82391ed5349SWolfram Sang } 82491ed5349SWolfram Sang 8251d7534b6SCharles Keepax int i2c_dev_irq_from_resources(const struct resource *resources, 82691ed5349SWolfram Sang unsigned int num_resources) 82791ed5349SWolfram Sang { 82891ed5349SWolfram Sang struct irq_data *irqd; 82991ed5349SWolfram Sang int i; 83091ed5349SWolfram Sang 83191ed5349SWolfram Sang for (i = 0; i < num_resources; i++) { 83291ed5349SWolfram Sang const struct resource *r = &resources[i]; 83391ed5349SWolfram Sang 83491ed5349SWolfram Sang if (resource_type(r) != IORESOURCE_IRQ) 83591ed5349SWolfram Sang continue; 83691ed5349SWolfram Sang 83791ed5349SWolfram Sang if (r->flags & IORESOURCE_BITS) { 83891ed5349SWolfram Sang irqd = irq_get_irq_data(r->start); 83991ed5349SWolfram Sang if (!irqd) 84091ed5349SWolfram Sang break; 84191ed5349SWolfram Sang 84291ed5349SWolfram Sang irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS); 84391ed5349SWolfram Sang } 84491ed5349SWolfram Sang 84591ed5349SWolfram Sang return r->start; 84691ed5349SWolfram Sang } 84791ed5349SWolfram Sang 84891ed5349SWolfram Sang return 0; 84991ed5349SWolfram Sang } 85091ed5349SWolfram Sang 85191ed5349SWolfram Sang /** 8527159dbdaSHeiner Kallweit * i2c_new_client_device - instantiate an i2c device 85391ed5349SWolfram Sang * @adap: the adapter managing the device 85491ed5349SWolfram Sang * @info: describes one I2C device; bus_num is ignored 85591ed5349SWolfram Sang * Context: can sleep 85691ed5349SWolfram Sang * 85791ed5349SWolfram Sang * Create an i2c device. Binding is handled through driver model 85891ed5349SWolfram Sang * probe()/remove() methods. A driver may be bound to this device when we 85991ed5349SWolfram Sang * return from this function, or any later moment (e.g. maybe hotplugging will 86091ed5349SWolfram Sang * load the driver module). This call is not appropriate for use by mainboard 86191ed5349SWolfram Sang * initialization logic, which usually runs during an arch_initcall() long 86291ed5349SWolfram Sang * before any i2c_adapter could exist. 86391ed5349SWolfram Sang * 86491ed5349SWolfram Sang * This returns the new i2c client, which may be saved for later use with 8657159dbdaSHeiner Kallweit * i2c_unregister_device(); or an ERR_PTR to describe the error. 86691ed5349SWolfram Sang */ 867550113d4SWolfram Sang struct i2c_client * 8687159dbdaSHeiner Kallweit i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) 86991ed5349SWolfram Sang { 87091ed5349SWolfram Sang struct i2c_client *client; 87191ed5349SWolfram Sang int status; 87291ed5349SWolfram Sang 87391ed5349SWolfram Sang client = kzalloc(sizeof *client, GFP_KERNEL); 87491ed5349SWolfram Sang if (!client) 8757159dbdaSHeiner Kallweit return ERR_PTR(-ENOMEM); 87691ed5349SWolfram Sang 87791ed5349SWolfram Sang client->adapter = adap; 87891ed5349SWolfram Sang 87991ed5349SWolfram Sang client->dev.platform_data = info->platform_data; 88091ed5349SWolfram Sang client->flags = info->flags; 88191ed5349SWolfram Sang client->addr = info->addr; 88291ed5349SWolfram Sang 88393b6604cSJim Broadus client->init_irq = info->irq; 88493b6604cSJim Broadus if (!client->init_irq) 88593b6604cSJim Broadus client->init_irq = i2c_dev_irq_from_resources(info->resources, 88691ed5349SWolfram Sang info->num_resources); 88791ed5349SWolfram Sang 88891ed5349SWolfram Sang strlcpy(client->name, info->type, sizeof(client->name)); 88991ed5349SWolfram Sang 89091ed5349SWolfram Sang status = i2c_check_addr_validity(client->addr, client->flags); 89191ed5349SWolfram Sang if (status) { 89291ed5349SWolfram Sang dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", 89391ed5349SWolfram Sang client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); 89491ed5349SWolfram Sang goto out_err_silent; 89591ed5349SWolfram Sang } 89691ed5349SWolfram Sang 89791ed5349SWolfram Sang /* Check for address business */ 89891ed5349SWolfram Sang status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); 89991ed5349SWolfram Sang if (status) 90091ed5349SWolfram Sang goto out_err; 90191ed5349SWolfram Sang 90291ed5349SWolfram Sang client->dev.parent = &client->adapter->dev; 90391ed5349SWolfram Sang client->dev.bus = &i2c_bus_type; 90491ed5349SWolfram Sang client->dev.type = &i2c_client_type; 90504782265SBoris Brezillon client->dev.of_node = of_node_get(info->of_node); 90691ed5349SWolfram Sang client->dev.fwnode = info->fwnode; 90791ed5349SWolfram Sang 908728fe6ceSHans de Goede i2c_dev_set_name(adap, client, info); 90991ed5349SWolfram Sang 91091ed5349SWolfram Sang if (info->properties) { 91191ed5349SWolfram Sang status = device_add_properties(&client->dev, info->properties); 91291ed5349SWolfram Sang if (status) { 91391ed5349SWolfram Sang dev_err(&adap->dev, 91491ed5349SWolfram Sang "Failed to add properties to client %s: %d\n", 91591ed5349SWolfram Sang client->name, status); 91604782265SBoris Brezillon goto out_err_put_of_node; 91791ed5349SWolfram Sang } 91891ed5349SWolfram Sang } 91991ed5349SWolfram Sang 92091ed5349SWolfram Sang status = device_register(&client->dev); 92191ed5349SWolfram Sang if (status) 92291ed5349SWolfram Sang goto out_free_props; 92391ed5349SWolfram Sang 92491ed5349SWolfram Sang dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", 92591ed5349SWolfram Sang client->name, dev_name(&client->dev)); 92691ed5349SWolfram Sang 92791ed5349SWolfram Sang return client; 92891ed5349SWolfram Sang 92991ed5349SWolfram Sang out_free_props: 93091ed5349SWolfram Sang if (info->properties) 93191ed5349SWolfram Sang device_remove_properties(&client->dev); 93204782265SBoris Brezillon out_err_put_of_node: 93304782265SBoris Brezillon of_node_put(info->of_node); 93491ed5349SWolfram Sang out_err: 93591ed5349SWolfram Sang dev_err(&adap->dev, 93691ed5349SWolfram Sang "Failed to register i2c client %s at 0x%02x (%d)\n", 93791ed5349SWolfram Sang client->name, client->addr, status); 93891ed5349SWolfram Sang out_err_silent: 93991ed5349SWolfram Sang kfree(client); 9407159dbdaSHeiner Kallweit return ERR_PTR(status); 9417159dbdaSHeiner Kallweit } 9427159dbdaSHeiner Kallweit EXPORT_SYMBOL_GPL(i2c_new_client_device); 9437159dbdaSHeiner Kallweit 9447159dbdaSHeiner Kallweit /** 94587e07437SWolfram Sang * i2c_unregister_device - reverse effect of i2c_new_*_device() 94687e07437SWolfram Sang * @client: value returned from i2c_new_*_device() 94791ed5349SWolfram Sang * Context: can sleep 94891ed5349SWolfram Sang */ 94991ed5349SWolfram Sang void i2c_unregister_device(struct i2c_client *client) 95091ed5349SWolfram Sang { 951689f5358SWolfram Sang if (IS_ERR_OR_NULL(client)) 9527b43dd19SAndy Shevchenko return; 953e0638fa4SLixin Wang 954e0638fa4SLixin Wang if (client->dev.of_node) { 95591ed5349SWolfram Sang of_node_clear_flag(client->dev.of_node, OF_POPULATED); 956e0638fa4SLixin Wang of_node_put(client->dev.of_node); 957e0638fa4SLixin Wang } 958e0638fa4SLixin Wang 95991ed5349SWolfram Sang if (ACPI_COMPANION(&client->dev)) 96091ed5349SWolfram Sang acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev)); 96191ed5349SWolfram Sang device_unregister(&client->dev); 96291ed5349SWolfram Sang } 96391ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_unregister_device); 96491ed5349SWolfram Sang 96591ed5349SWolfram Sang 96691ed5349SWolfram Sang static const struct i2c_device_id dummy_id[] = { 96791ed5349SWolfram Sang { "dummy", 0 }, 96891ed5349SWolfram Sang { }, 96991ed5349SWolfram Sang }; 97091ed5349SWolfram Sang 97191ed5349SWolfram Sang static int dummy_probe(struct i2c_client *client, 97291ed5349SWolfram Sang const struct i2c_device_id *id) 97391ed5349SWolfram Sang { 97491ed5349SWolfram Sang return 0; 97591ed5349SWolfram Sang } 97691ed5349SWolfram Sang 97791ed5349SWolfram Sang static int dummy_remove(struct i2c_client *client) 97891ed5349SWolfram Sang { 97991ed5349SWolfram Sang return 0; 98091ed5349SWolfram Sang } 98191ed5349SWolfram Sang 98291ed5349SWolfram Sang static struct i2c_driver dummy_driver = { 98391ed5349SWolfram Sang .driver.name = "dummy", 98491ed5349SWolfram Sang .probe = dummy_probe, 98591ed5349SWolfram Sang .remove = dummy_remove, 98691ed5349SWolfram Sang .id_table = dummy_id, 98791ed5349SWolfram Sang }; 98891ed5349SWolfram Sang 98991ed5349SWolfram Sang /** 9907159dbdaSHeiner Kallweit * i2c_new_dummy_device - return a new i2c device bound to a dummy driver 99191ed5349SWolfram Sang * @adapter: the adapter managing the device 99291ed5349SWolfram Sang * @address: seven bit address to be used 99391ed5349SWolfram Sang * Context: can sleep 99491ed5349SWolfram Sang * 99591ed5349SWolfram Sang * This returns an I2C client bound to the "dummy" driver, intended for use 99691ed5349SWolfram Sang * with devices that consume multiple addresses. Examples of such chips 99791ed5349SWolfram Sang * include various EEPROMS (like 24c04 and 24c08 models). 99891ed5349SWolfram Sang * 99991ed5349SWolfram Sang * These dummy devices have two main uses. First, most I2C and SMBus calls 100091ed5349SWolfram Sang * except i2c_transfer() need a client handle; the dummy will be that handle. 100191ed5349SWolfram Sang * And second, this prevents the specified address from being bound to a 100291ed5349SWolfram Sang * different driver. 100391ed5349SWolfram Sang * 100491ed5349SWolfram Sang * This returns the new i2c client, which should be saved for later use with 10057159dbdaSHeiner Kallweit * i2c_unregister_device(); or an ERR_PTR to describe the error. 100691ed5349SWolfram Sang */ 1007550113d4SWolfram Sang struct i2c_client *i2c_new_dummy_device(struct i2c_adapter *adapter, u16 address) 100891ed5349SWolfram Sang { 100991ed5349SWolfram Sang struct i2c_board_info info = { 101091ed5349SWolfram Sang I2C_BOARD_INFO("dummy", address), 101191ed5349SWolfram Sang }; 101291ed5349SWolfram Sang 10137159dbdaSHeiner Kallweit return i2c_new_client_device(adapter, &info); 10147159dbdaSHeiner Kallweit } 10157159dbdaSHeiner Kallweit EXPORT_SYMBOL_GPL(i2c_new_dummy_device); 10167159dbdaSHeiner Kallweit 1017b8f5fe3bSHeiner Kallweit struct i2c_dummy_devres { 1018b8f5fe3bSHeiner Kallweit struct i2c_client *client; 1019b8f5fe3bSHeiner Kallweit }; 1020b8f5fe3bSHeiner Kallweit 1021b8f5fe3bSHeiner Kallweit static void devm_i2c_release_dummy(struct device *dev, void *res) 1022b8f5fe3bSHeiner Kallweit { 1023b8f5fe3bSHeiner Kallweit struct i2c_dummy_devres *this = res; 1024b8f5fe3bSHeiner Kallweit 1025b8f5fe3bSHeiner Kallweit i2c_unregister_device(this->client); 1026b8f5fe3bSHeiner Kallweit } 1027b8f5fe3bSHeiner Kallweit 1028b8f5fe3bSHeiner Kallweit /** 1029b8f5fe3bSHeiner Kallweit * devm_i2c_new_dummy_device - return a new i2c device bound to a dummy driver 1030b8f5fe3bSHeiner Kallweit * @dev: device the managed resource is bound to 1031b8f5fe3bSHeiner Kallweit * @adapter: the adapter managing the device 1032b8f5fe3bSHeiner Kallweit * @address: seven bit address to be used 1033b8f5fe3bSHeiner Kallweit * Context: can sleep 1034b8f5fe3bSHeiner Kallweit * 1035b8f5fe3bSHeiner Kallweit * This is the device-managed version of @i2c_new_dummy_device. It returns the 1036b8f5fe3bSHeiner Kallweit * new i2c client or an ERR_PTR in case of an error. 1037b8f5fe3bSHeiner Kallweit */ 1038b8f5fe3bSHeiner Kallweit struct i2c_client *devm_i2c_new_dummy_device(struct device *dev, 1039b8f5fe3bSHeiner Kallweit struct i2c_adapter *adapter, 1040b8f5fe3bSHeiner Kallweit u16 address) 1041b8f5fe3bSHeiner Kallweit { 1042b8f5fe3bSHeiner Kallweit struct i2c_dummy_devres *dr; 1043b8f5fe3bSHeiner Kallweit struct i2c_client *client; 1044b8f5fe3bSHeiner Kallweit 1045b8f5fe3bSHeiner Kallweit dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); 1046b8f5fe3bSHeiner Kallweit if (!dr) 1047b8f5fe3bSHeiner Kallweit return ERR_PTR(-ENOMEM); 1048b8f5fe3bSHeiner Kallweit 1049b8f5fe3bSHeiner Kallweit client = i2c_new_dummy_device(adapter, address); 1050b8f5fe3bSHeiner Kallweit if (IS_ERR(client)) { 1051b8f5fe3bSHeiner Kallweit devres_free(dr); 1052b8f5fe3bSHeiner Kallweit } else { 1053b8f5fe3bSHeiner Kallweit dr->client = client; 1054b8f5fe3bSHeiner Kallweit devres_add(dev, dr); 1055b8f5fe3bSHeiner Kallweit } 1056b8f5fe3bSHeiner Kallweit 1057b8f5fe3bSHeiner Kallweit return client; 1058b8f5fe3bSHeiner Kallweit } 1059b8f5fe3bSHeiner Kallweit EXPORT_SYMBOL_GPL(devm_i2c_new_dummy_device); 1060b8f5fe3bSHeiner Kallweit 106191ed5349SWolfram Sang /** 1062af80559bSWolfram Sang * i2c_new_ancillary_device - Helper to get the instantiated secondary address 106391ed5349SWolfram Sang * and create the associated device 106491ed5349SWolfram Sang * @client: Handle to the primary client 106591ed5349SWolfram Sang * @name: Handle to specify which secondary address to get 106691ed5349SWolfram Sang * @default_addr: Used as a fallback if no secondary address was specified 106791ed5349SWolfram Sang * Context: can sleep 106891ed5349SWolfram Sang * 106991ed5349SWolfram Sang * I2C clients can be composed of multiple I2C slaves bound together in a single 107091ed5349SWolfram Sang * component. The I2C client driver then binds to the master I2C slave and needs 107191ed5349SWolfram Sang * to create I2C dummy clients to communicate with all the other slaves. 107291ed5349SWolfram Sang * 107391ed5349SWolfram Sang * This function creates and returns an I2C dummy client whose I2C address is 107491ed5349SWolfram Sang * retrieved from the platform firmware based on the given slave name. If no 107591ed5349SWolfram Sang * address is specified by the firmware default_addr is used. 107691ed5349SWolfram Sang * 107791ed5349SWolfram Sang * On DT-based platforms the address is retrieved from the "reg" property entry 107891ed5349SWolfram Sang * cell whose "reg-names" value matches the slave name. 107991ed5349SWolfram Sang * 108091ed5349SWolfram Sang * This returns the new i2c client, which should be saved for later use with 1081af80559bSWolfram Sang * i2c_unregister_device(); or an ERR_PTR to describe the error. 108291ed5349SWolfram Sang */ 1083af80559bSWolfram Sang struct i2c_client *i2c_new_ancillary_device(struct i2c_client *client, 108491ed5349SWolfram Sang const char *name, 108591ed5349SWolfram Sang u16 default_addr) 108691ed5349SWolfram Sang { 108791ed5349SWolfram Sang struct device_node *np = client->dev.of_node; 108891ed5349SWolfram Sang u32 addr = default_addr; 108991ed5349SWolfram Sang int i; 109091ed5349SWolfram Sang 109191ed5349SWolfram Sang if (np) { 109291ed5349SWolfram Sang i = of_property_match_string(np, "reg-names", name); 109391ed5349SWolfram Sang if (i >= 0) 109491ed5349SWolfram Sang of_property_read_u32_index(np, "reg", i, &addr); 109591ed5349SWolfram Sang } 109691ed5349SWolfram Sang 109791ed5349SWolfram Sang dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); 1098af80559bSWolfram Sang return i2c_new_dummy_device(client->adapter, addr); 109991ed5349SWolfram Sang } 1100af80559bSWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_ancillary_device); 110191ed5349SWolfram Sang 110291ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 110391ed5349SWolfram Sang 110491ed5349SWolfram Sang /* I2C bus adapters -- one roots each I2C or SMBUS segment */ 110591ed5349SWolfram Sang 110691ed5349SWolfram Sang static void i2c_adapter_dev_release(struct device *dev) 110791ed5349SWolfram Sang { 110891ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 110991ed5349SWolfram Sang complete(&adap->dev_released); 111091ed5349SWolfram Sang } 111191ed5349SWolfram Sang 111291ed5349SWolfram Sang unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) 111391ed5349SWolfram Sang { 111491ed5349SWolfram Sang unsigned int depth = 0; 111591ed5349SWolfram Sang 111691ed5349SWolfram Sang while ((adapter = i2c_parent_is_i2c_adapter(adapter))) 111791ed5349SWolfram Sang depth++; 111891ed5349SWolfram Sang 111991ed5349SWolfram Sang WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES, 112091ed5349SWolfram Sang "adapter depth exceeds lockdep subclass limit\n"); 112191ed5349SWolfram Sang 112291ed5349SWolfram Sang return depth; 112391ed5349SWolfram Sang } 112491ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_adapter_depth); 112591ed5349SWolfram Sang 112691ed5349SWolfram Sang /* 112791ed5349SWolfram Sang * Let users instantiate I2C devices through sysfs. This can be used when 112891ed5349SWolfram Sang * platform initialization code doesn't contain the proper data for 112991ed5349SWolfram Sang * whatever reason. Also useful for drivers that do device detection and 113091ed5349SWolfram Sang * detection fails, either because the device uses an unexpected address, 113191ed5349SWolfram Sang * or this is a compatible device with different ID register values. 113291ed5349SWolfram Sang * 113391ed5349SWolfram Sang * Parameter checking may look overzealous, but we really don't want 113491ed5349SWolfram Sang * the user to provide incorrect parameters. 113591ed5349SWolfram Sang */ 113691ed5349SWolfram Sang static ssize_t 113754a19fd4SGeert Uytterhoeven new_device_store(struct device *dev, struct device_attribute *attr, 113891ed5349SWolfram Sang const char *buf, size_t count) 113991ed5349SWolfram Sang { 114091ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 114191ed5349SWolfram Sang struct i2c_board_info info; 114291ed5349SWolfram Sang struct i2c_client *client; 114391ed5349SWolfram Sang char *blank, end; 114491ed5349SWolfram Sang int res; 114591ed5349SWolfram Sang 114691ed5349SWolfram Sang memset(&info, 0, sizeof(struct i2c_board_info)); 114791ed5349SWolfram Sang 114891ed5349SWolfram Sang blank = strchr(buf, ' '); 114991ed5349SWolfram Sang if (!blank) { 115091ed5349SWolfram Sang dev_err(dev, "%s: Missing parameters\n", "new_device"); 115191ed5349SWolfram Sang return -EINVAL; 115291ed5349SWolfram Sang } 115391ed5349SWolfram Sang if (blank - buf > I2C_NAME_SIZE - 1) { 115491ed5349SWolfram Sang dev_err(dev, "%s: Invalid device name\n", "new_device"); 115591ed5349SWolfram Sang return -EINVAL; 115691ed5349SWolfram Sang } 115791ed5349SWolfram Sang memcpy(info.type, buf, blank - buf); 115891ed5349SWolfram Sang 115991ed5349SWolfram Sang /* Parse remaining parameters, reject extra parameters */ 116091ed5349SWolfram Sang res = sscanf(++blank, "%hi%c", &info.addr, &end); 116191ed5349SWolfram Sang if (res < 1) { 116291ed5349SWolfram Sang dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); 116391ed5349SWolfram Sang return -EINVAL; 116491ed5349SWolfram Sang } 116591ed5349SWolfram Sang if (res > 1 && end != '\n') { 116691ed5349SWolfram Sang dev_err(dev, "%s: Extra parameters\n", "new_device"); 116791ed5349SWolfram Sang return -EINVAL; 116891ed5349SWolfram Sang } 116991ed5349SWolfram Sang 117091ed5349SWolfram Sang if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { 117191ed5349SWolfram Sang info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; 117291ed5349SWolfram Sang info.flags |= I2C_CLIENT_TEN; 117391ed5349SWolfram Sang } 117491ed5349SWolfram Sang 117591ed5349SWolfram Sang if (info.addr & I2C_ADDR_OFFSET_SLAVE) { 117691ed5349SWolfram Sang info.addr &= ~I2C_ADDR_OFFSET_SLAVE; 117791ed5349SWolfram Sang info.flags |= I2C_CLIENT_SLAVE; 117891ed5349SWolfram Sang } 117991ed5349SWolfram Sang 11807159dbdaSHeiner Kallweit client = i2c_new_client_device(adap, &info); 11817159dbdaSHeiner Kallweit if (IS_ERR(client)) 11827159dbdaSHeiner Kallweit return PTR_ERR(client); 118391ed5349SWolfram Sang 118491ed5349SWolfram Sang /* Keep track of the added device */ 118591ed5349SWolfram Sang mutex_lock(&adap->userspace_clients_lock); 118691ed5349SWolfram Sang list_add_tail(&client->detected, &adap->userspace_clients); 118791ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 118891ed5349SWolfram Sang dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", 118991ed5349SWolfram Sang info.type, info.addr); 119091ed5349SWolfram Sang 119191ed5349SWolfram Sang return count; 119291ed5349SWolfram Sang } 119354a19fd4SGeert Uytterhoeven static DEVICE_ATTR_WO(new_device); 119491ed5349SWolfram Sang 119591ed5349SWolfram Sang /* 119691ed5349SWolfram Sang * And of course let the users delete the devices they instantiated, if 119791ed5349SWolfram Sang * they got it wrong. This interface can only be used to delete devices 119891ed5349SWolfram Sang * instantiated by i2c_sysfs_new_device above. This guarantees that we 119991ed5349SWolfram Sang * don't delete devices to which some kernel code still has references. 120091ed5349SWolfram Sang * 120191ed5349SWolfram Sang * Parameter checking may look overzealous, but we really don't want 120291ed5349SWolfram Sang * the user to delete the wrong device. 120391ed5349SWolfram Sang */ 120491ed5349SWolfram Sang static ssize_t 120554a19fd4SGeert Uytterhoeven delete_device_store(struct device *dev, struct device_attribute *attr, 120691ed5349SWolfram Sang const char *buf, size_t count) 120791ed5349SWolfram Sang { 120891ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 120991ed5349SWolfram Sang struct i2c_client *client, *next; 121091ed5349SWolfram Sang unsigned short addr; 121191ed5349SWolfram Sang char end; 121291ed5349SWolfram Sang int res; 121391ed5349SWolfram Sang 121491ed5349SWolfram Sang /* Parse parameters, reject extra parameters */ 121591ed5349SWolfram Sang res = sscanf(buf, "%hi%c", &addr, &end); 121691ed5349SWolfram Sang if (res < 1) { 121791ed5349SWolfram Sang dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); 121891ed5349SWolfram Sang return -EINVAL; 121991ed5349SWolfram Sang } 122091ed5349SWolfram Sang if (res > 1 && end != '\n') { 122191ed5349SWolfram Sang dev_err(dev, "%s: Extra parameters\n", "delete_device"); 122291ed5349SWolfram Sang return -EINVAL; 122391ed5349SWolfram Sang } 122491ed5349SWolfram Sang 122591ed5349SWolfram Sang /* Make sure the device was added through sysfs */ 122691ed5349SWolfram Sang res = -ENOENT; 122791ed5349SWolfram Sang mutex_lock_nested(&adap->userspace_clients_lock, 122891ed5349SWolfram Sang i2c_adapter_depth(adap)); 122991ed5349SWolfram Sang list_for_each_entry_safe(client, next, &adap->userspace_clients, 123091ed5349SWolfram Sang detected) { 123191ed5349SWolfram Sang if (i2c_encode_flags_to_addr(client) == addr) { 123291ed5349SWolfram Sang dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", 123391ed5349SWolfram Sang "delete_device", client->name, client->addr); 123491ed5349SWolfram Sang 123591ed5349SWolfram Sang list_del(&client->detected); 123691ed5349SWolfram Sang i2c_unregister_device(client); 123791ed5349SWolfram Sang res = count; 123891ed5349SWolfram Sang break; 123991ed5349SWolfram Sang } 124091ed5349SWolfram Sang } 124191ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 124291ed5349SWolfram Sang 124391ed5349SWolfram Sang if (res < 0) 124491ed5349SWolfram Sang dev_err(dev, "%s: Can't find device in list\n", 124591ed5349SWolfram Sang "delete_device"); 124691ed5349SWolfram Sang return res; 124791ed5349SWolfram Sang } 124891ed5349SWolfram Sang static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, 124954a19fd4SGeert Uytterhoeven delete_device_store); 125091ed5349SWolfram Sang 125191ed5349SWolfram Sang static struct attribute *i2c_adapter_attrs[] = { 125291ed5349SWolfram Sang &dev_attr_name.attr, 125391ed5349SWolfram Sang &dev_attr_new_device.attr, 125491ed5349SWolfram Sang &dev_attr_delete_device.attr, 125591ed5349SWolfram Sang NULL 125691ed5349SWolfram Sang }; 125791ed5349SWolfram Sang ATTRIBUTE_GROUPS(i2c_adapter); 125891ed5349SWolfram Sang 125991ed5349SWolfram Sang struct device_type i2c_adapter_type = { 126091ed5349SWolfram Sang .groups = i2c_adapter_groups, 126191ed5349SWolfram Sang .release = i2c_adapter_dev_release, 126291ed5349SWolfram Sang }; 126391ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_adapter_type); 126491ed5349SWolfram Sang 126591ed5349SWolfram Sang /** 126691ed5349SWolfram Sang * i2c_verify_adapter - return parameter as i2c_adapter or NULL 126791ed5349SWolfram Sang * @dev: device, probably from some driver model iterator 126891ed5349SWolfram Sang * 126991ed5349SWolfram Sang * When traversing the driver model tree, perhaps using driver model 127091ed5349SWolfram Sang * iterators like @device_for_each_child(), you can't assume very much 127191ed5349SWolfram Sang * about the nodes you find. Use this function to avoid oopses caused 127291ed5349SWolfram Sang * by wrongly treating some non-I2C device as an i2c_adapter. 127391ed5349SWolfram Sang */ 127491ed5349SWolfram Sang struct i2c_adapter *i2c_verify_adapter(struct device *dev) 127591ed5349SWolfram Sang { 127691ed5349SWolfram Sang return (dev->type == &i2c_adapter_type) 127791ed5349SWolfram Sang ? to_i2c_adapter(dev) 127891ed5349SWolfram Sang : NULL; 127991ed5349SWolfram Sang } 128091ed5349SWolfram Sang EXPORT_SYMBOL(i2c_verify_adapter); 128191ed5349SWolfram Sang 128291ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 128391ed5349SWolfram Sang static struct class_compat *i2c_adapter_compat_class; 128491ed5349SWolfram Sang #endif 128591ed5349SWolfram Sang 128691ed5349SWolfram Sang static void i2c_scan_static_board_info(struct i2c_adapter *adapter) 128791ed5349SWolfram Sang { 128891ed5349SWolfram Sang struct i2c_devinfo *devinfo; 128991ed5349SWolfram Sang 129091ed5349SWolfram Sang down_read(&__i2c_board_lock); 129191ed5349SWolfram Sang list_for_each_entry(devinfo, &__i2c_board_list, list) { 129287e07437SWolfram Sang if (devinfo->busnum == adapter->nr && 129387e07437SWolfram Sang IS_ERR(i2c_new_client_device(adapter, &devinfo->board_info))) 129491ed5349SWolfram Sang dev_err(&adapter->dev, 129591ed5349SWolfram Sang "Can't create device at 0x%02x\n", 129691ed5349SWolfram Sang devinfo->board_info.addr); 129791ed5349SWolfram Sang } 129891ed5349SWolfram Sang up_read(&__i2c_board_lock); 129991ed5349SWolfram Sang } 130091ed5349SWolfram Sang 130191ed5349SWolfram Sang static int i2c_do_add_adapter(struct i2c_driver *driver, 130291ed5349SWolfram Sang struct i2c_adapter *adap) 130391ed5349SWolfram Sang { 130491ed5349SWolfram Sang /* Detect supported devices on that bus, and instantiate them */ 130591ed5349SWolfram Sang i2c_detect(adap, driver); 130691ed5349SWolfram Sang 130791ed5349SWolfram Sang return 0; 130891ed5349SWolfram Sang } 130991ed5349SWolfram Sang 131091ed5349SWolfram Sang static int __process_new_adapter(struct device_driver *d, void *data) 131191ed5349SWolfram Sang { 131291ed5349SWolfram Sang return i2c_do_add_adapter(to_i2c_driver(d), data); 131391ed5349SWolfram Sang } 131491ed5349SWolfram Sang 131591ed5349SWolfram Sang static const struct i2c_lock_operations i2c_adapter_lock_ops = { 131691ed5349SWolfram Sang .lock_bus = i2c_adapter_lock_bus, 131791ed5349SWolfram Sang .trylock_bus = i2c_adapter_trylock_bus, 131891ed5349SWolfram Sang .unlock_bus = i2c_adapter_unlock_bus, 131991ed5349SWolfram Sang }; 132091ed5349SWolfram Sang 132191ed5349SWolfram Sang static void i2c_host_notify_irq_teardown(struct i2c_adapter *adap) 132291ed5349SWolfram Sang { 132391ed5349SWolfram Sang struct irq_domain *domain = adap->host_notify_domain; 132491ed5349SWolfram Sang irq_hw_number_t hwirq; 132591ed5349SWolfram Sang 132691ed5349SWolfram Sang if (!domain) 132791ed5349SWolfram Sang return; 132891ed5349SWolfram Sang 132991ed5349SWolfram Sang for (hwirq = 0 ; hwirq < I2C_ADDR_7BITS_COUNT ; hwirq++) 133091ed5349SWolfram Sang irq_dispose_mapping(irq_find_mapping(domain, hwirq)); 133191ed5349SWolfram Sang 133291ed5349SWolfram Sang irq_domain_remove(domain); 133391ed5349SWolfram Sang adap->host_notify_domain = NULL; 133491ed5349SWolfram Sang } 133591ed5349SWolfram Sang 133691ed5349SWolfram Sang static int i2c_host_notify_irq_map(struct irq_domain *h, 133791ed5349SWolfram Sang unsigned int virq, 133891ed5349SWolfram Sang irq_hw_number_t hw_irq_num) 133991ed5349SWolfram Sang { 134091ed5349SWolfram Sang irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); 134191ed5349SWolfram Sang 134291ed5349SWolfram Sang return 0; 134391ed5349SWolfram Sang } 134491ed5349SWolfram Sang 134591ed5349SWolfram Sang static const struct irq_domain_ops i2c_host_notify_irq_ops = { 134691ed5349SWolfram Sang .map = i2c_host_notify_irq_map, 134791ed5349SWolfram Sang }; 134891ed5349SWolfram Sang 134991ed5349SWolfram Sang static int i2c_setup_host_notify_irq_domain(struct i2c_adapter *adap) 135091ed5349SWolfram Sang { 135191ed5349SWolfram Sang struct irq_domain *domain; 135291ed5349SWolfram Sang 135391ed5349SWolfram Sang if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_HOST_NOTIFY)) 135491ed5349SWolfram Sang return 0; 135591ed5349SWolfram Sang 13568682dc12SWolfram Sang domain = irq_domain_create_linear(adap->dev.parent->fwnode, 135791ed5349SWolfram Sang I2C_ADDR_7BITS_COUNT, 135891ed5349SWolfram Sang &i2c_host_notify_irq_ops, adap); 135991ed5349SWolfram Sang if (!domain) 136091ed5349SWolfram Sang return -ENOMEM; 136191ed5349SWolfram Sang 136291ed5349SWolfram Sang adap->host_notify_domain = domain; 136391ed5349SWolfram Sang 136491ed5349SWolfram Sang return 0; 136591ed5349SWolfram Sang } 136691ed5349SWolfram Sang 136791ed5349SWolfram Sang /** 136891ed5349SWolfram Sang * i2c_handle_smbus_host_notify - Forward a Host Notify event to the correct 136991ed5349SWolfram Sang * I2C client. 137091ed5349SWolfram Sang * @adap: the adapter 137191ed5349SWolfram Sang * @addr: the I2C address of the notifying device 137291ed5349SWolfram Sang * Context: can't sleep 137391ed5349SWolfram Sang * 137491ed5349SWolfram Sang * Helper function to be called from an I2C bus driver's interrupt 137591ed5349SWolfram Sang * handler. It will schedule the Host Notify IRQ. 137691ed5349SWolfram Sang */ 137791ed5349SWolfram Sang int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr) 137891ed5349SWolfram Sang { 137991ed5349SWolfram Sang int irq; 138091ed5349SWolfram Sang 138191ed5349SWolfram Sang if (!adap) 138291ed5349SWolfram Sang return -EINVAL; 138391ed5349SWolfram Sang 138491ed5349SWolfram Sang irq = irq_find_mapping(adap->host_notify_domain, addr); 138591ed5349SWolfram Sang if (irq <= 0) 138691ed5349SWolfram Sang return -ENXIO; 138791ed5349SWolfram Sang 138891ed5349SWolfram Sang generic_handle_irq(irq); 138991ed5349SWolfram Sang 139091ed5349SWolfram Sang return 0; 139191ed5349SWolfram Sang } 139291ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify); 139391ed5349SWolfram Sang 139491ed5349SWolfram Sang static int i2c_register_adapter(struct i2c_adapter *adap) 139591ed5349SWolfram Sang { 139691ed5349SWolfram Sang int res = -EINVAL; 139791ed5349SWolfram Sang 139891ed5349SWolfram Sang /* Can't register until after driver model init */ 139991ed5349SWolfram Sang if (WARN_ON(!is_registered)) { 140091ed5349SWolfram Sang res = -EAGAIN; 140191ed5349SWolfram Sang goto out_list; 140291ed5349SWolfram Sang } 140391ed5349SWolfram Sang 140491ed5349SWolfram Sang /* Sanity checks */ 140591ed5349SWolfram Sang if (WARN(!adap->name[0], "i2c adapter has no name")) 140691ed5349SWolfram Sang goto out_list; 140791ed5349SWolfram Sang 140891ed5349SWolfram Sang if (!adap->algo) { 140991ed5349SWolfram Sang pr_err("adapter '%s': no algo supplied!\n", adap->name); 141091ed5349SWolfram Sang goto out_list; 141191ed5349SWolfram Sang } 141291ed5349SWolfram Sang 141391ed5349SWolfram Sang if (!adap->lock_ops) 141491ed5349SWolfram Sang adap->lock_ops = &i2c_adapter_lock_ops; 141591ed5349SWolfram Sang 14169ac6cb5fSWolfram Sang adap->locked_flags = 0; 141791ed5349SWolfram Sang rt_mutex_init(&adap->bus_lock); 141891ed5349SWolfram Sang rt_mutex_init(&adap->mux_lock); 141991ed5349SWolfram Sang mutex_init(&adap->userspace_clients_lock); 142091ed5349SWolfram Sang INIT_LIST_HEAD(&adap->userspace_clients); 142191ed5349SWolfram Sang 142291ed5349SWolfram Sang /* Set default timeout to 1 second if not already set */ 142391ed5349SWolfram Sang if (adap->timeout == 0) 142491ed5349SWolfram Sang adap->timeout = HZ; 142591ed5349SWolfram Sang 142691ed5349SWolfram Sang /* register soft irqs for Host Notify */ 142791ed5349SWolfram Sang res = i2c_setup_host_notify_irq_domain(adap); 142891ed5349SWolfram Sang if (res) { 142991ed5349SWolfram Sang pr_err("adapter '%s': can't create Host Notify IRQs (%d)\n", 143091ed5349SWolfram Sang adap->name, res); 143191ed5349SWolfram Sang goto out_list; 143291ed5349SWolfram Sang } 143391ed5349SWolfram Sang 143491ed5349SWolfram Sang dev_set_name(&adap->dev, "i2c-%d", adap->nr); 143591ed5349SWolfram Sang adap->dev.bus = &i2c_bus_type; 143691ed5349SWolfram Sang adap->dev.type = &i2c_adapter_type; 143791ed5349SWolfram Sang res = device_register(&adap->dev); 143891ed5349SWolfram Sang if (res) { 143991ed5349SWolfram Sang pr_err("adapter '%s': can't register device (%d)\n", adap->name, res); 144091ed5349SWolfram Sang goto out_list; 144191ed5349SWolfram Sang } 144291ed5349SWolfram Sang 1443f8756c67SPhil Reid res = of_i2c_setup_smbus_alert(adap); 1444f8756c67SPhil Reid if (res) 1445f8756c67SPhil Reid goto out_reg; 1446f8756c67SPhil Reid 144791ed5349SWolfram Sang pm_runtime_no_callbacks(&adap->dev); 144891ed5349SWolfram Sang pm_suspend_ignore_children(&adap->dev, true); 144991ed5349SWolfram Sang pm_runtime_enable(&adap->dev); 145091ed5349SWolfram Sang 145123a698feSCodrin Ciubotariu res = i2c_init_recovery(adap); 145223a698feSCodrin Ciubotariu if (res == -EPROBE_DEFER) 145323a698feSCodrin Ciubotariu goto out_reg; 145423a698feSCodrin Ciubotariu 145523a698feSCodrin Ciubotariu dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); 145623a698feSCodrin Ciubotariu 145791ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 145891ed5349SWolfram Sang res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, 145991ed5349SWolfram Sang adap->dev.parent); 146091ed5349SWolfram Sang if (res) 146191ed5349SWolfram Sang dev_warn(&adap->dev, 146291ed5349SWolfram Sang "Failed to create compatibility class link\n"); 146391ed5349SWolfram Sang #endif 146491ed5349SWolfram Sang 146591ed5349SWolfram Sang /* create pre-declared device nodes */ 146691ed5349SWolfram Sang of_i2c_register_devices(adap); 146791ed5349SWolfram Sang i2c_acpi_install_space_handler(adap); 1468*21653a41SHans de Goede i2c_acpi_register_devices(adap); 146991ed5349SWolfram Sang 147091ed5349SWolfram Sang if (adap->nr < __i2c_first_dynamic_bus_num) 147191ed5349SWolfram Sang i2c_scan_static_board_info(adap); 147291ed5349SWolfram Sang 147391ed5349SWolfram Sang /* Notify drivers */ 147491ed5349SWolfram Sang mutex_lock(&core_lock); 147591ed5349SWolfram Sang bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); 147691ed5349SWolfram Sang mutex_unlock(&core_lock); 147791ed5349SWolfram Sang 147891ed5349SWolfram Sang return 0; 147991ed5349SWolfram Sang 1480f8756c67SPhil Reid out_reg: 1481f8756c67SPhil Reid init_completion(&adap->dev_released); 1482f8756c67SPhil Reid device_unregister(&adap->dev); 1483f8756c67SPhil Reid wait_for_completion(&adap->dev_released); 148491ed5349SWolfram Sang out_list: 148591ed5349SWolfram Sang mutex_lock(&core_lock); 148691ed5349SWolfram Sang idr_remove(&i2c_adapter_idr, adap->nr); 148791ed5349SWolfram Sang mutex_unlock(&core_lock); 148891ed5349SWolfram Sang return res; 148991ed5349SWolfram Sang } 149091ed5349SWolfram Sang 149191ed5349SWolfram Sang /** 149291ed5349SWolfram Sang * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 149391ed5349SWolfram Sang * @adap: the adapter to register (with adap->nr initialized) 149491ed5349SWolfram Sang * Context: can sleep 149591ed5349SWolfram Sang * 149691ed5349SWolfram Sang * See i2c_add_numbered_adapter() for details. 149791ed5349SWolfram Sang */ 149891ed5349SWolfram Sang static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) 149991ed5349SWolfram Sang { 150091ed5349SWolfram Sang int id; 150191ed5349SWolfram Sang 150291ed5349SWolfram Sang mutex_lock(&core_lock); 150391ed5349SWolfram Sang id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); 150491ed5349SWolfram Sang mutex_unlock(&core_lock); 150591ed5349SWolfram Sang if (WARN(id < 0, "couldn't get idr")) 150691ed5349SWolfram Sang return id == -ENOSPC ? -EBUSY : id; 150791ed5349SWolfram Sang 150891ed5349SWolfram Sang return i2c_register_adapter(adap); 150991ed5349SWolfram Sang } 151091ed5349SWolfram Sang 151191ed5349SWolfram Sang /** 151291ed5349SWolfram Sang * i2c_add_adapter - declare i2c adapter, use dynamic bus number 151391ed5349SWolfram Sang * @adapter: the adapter to add 151491ed5349SWolfram Sang * Context: can sleep 151591ed5349SWolfram Sang * 151691ed5349SWolfram Sang * This routine is used to declare an I2C adapter when its bus number 151791ed5349SWolfram Sang * doesn't matter or when its bus number is specified by an dt alias. 151891ed5349SWolfram Sang * Examples of bases when the bus number doesn't matter: I2C adapters 151991ed5349SWolfram Sang * dynamically added by USB links or PCI plugin cards. 152091ed5349SWolfram Sang * 152191ed5349SWolfram Sang * When this returns zero, a new bus number was allocated and stored 152291ed5349SWolfram Sang * in adap->nr, and the specified adapter became available for clients. 152391ed5349SWolfram Sang * Otherwise, a negative errno value is returned. 152491ed5349SWolfram Sang */ 152591ed5349SWolfram Sang int i2c_add_adapter(struct i2c_adapter *adapter) 152691ed5349SWolfram Sang { 152791ed5349SWolfram Sang struct device *dev = &adapter->dev; 152891ed5349SWolfram Sang int id; 152991ed5349SWolfram Sang 153091ed5349SWolfram Sang if (dev->of_node) { 153191ed5349SWolfram Sang id = of_alias_get_id(dev->of_node, "i2c"); 153291ed5349SWolfram Sang if (id >= 0) { 153391ed5349SWolfram Sang adapter->nr = id; 153491ed5349SWolfram Sang return __i2c_add_numbered_adapter(adapter); 153591ed5349SWolfram Sang } 153691ed5349SWolfram Sang } 153791ed5349SWolfram Sang 153891ed5349SWolfram Sang mutex_lock(&core_lock); 153991ed5349SWolfram Sang id = idr_alloc(&i2c_adapter_idr, adapter, 154091ed5349SWolfram Sang __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); 154191ed5349SWolfram Sang mutex_unlock(&core_lock); 154291ed5349SWolfram Sang if (WARN(id < 0, "couldn't get idr")) 154391ed5349SWolfram Sang return id; 154491ed5349SWolfram Sang 154591ed5349SWolfram Sang adapter->nr = id; 154691ed5349SWolfram Sang 154791ed5349SWolfram Sang return i2c_register_adapter(adapter); 154891ed5349SWolfram Sang } 154991ed5349SWolfram Sang EXPORT_SYMBOL(i2c_add_adapter); 155091ed5349SWolfram Sang 155191ed5349SWolfram Sang /** 155291ed5349SWolfram Sang * i2c_add_numbered_adapter - declare i2c adapter, use static bus number 155391ed5349SWolfram Sang * @adap: the adapter to register (with adap->nr initialized) 155491ed5349SWolfram Sang * Context: can sleep 155591ed5349SWolfram Sang * 155691ed5349SWolfram Sang * This routine is used to declare an I2C adapter when its bus number 155791ed5349SWolfram Sang * matters. For example, use it for I2C adapters from system-on-chip CPUs, 155891ed5349SWolfram Sang * or otherwise built in to the system's mainboard, and where i2c_board_info 155991ed5349SWolfram Sang * is used to properly configure I2C devices. 156091ed5349SWolfram Sang * 156191ed5349SWolfram Sang * If the requested bus number is set to -1, then this function will behave 156291ed5349SWolfram Sang * identically to i2c_add_adapter, and will dynamically assign a bus number. 156391ed5349SWolfram Sang * 156491ed5349SWolfram Sang * If no devices have pre-been declared for this bus, then be sure to 156591ed5349SWolfram Sang * register the adapter before any dynamically allocated ones. Otherwise 156691ed5349SWolfram Sang * the required bus ID may not be available. 156791ed5349SWolfram Sang * 156891ed5349SWolfram Sang * When this returns zero, the specified adapter became available for 156991ed5349SWolfram Sang * clients using the bus number provided in adap->nr. Also, the table 157091ed5349SWolfram Sang * of I2C devices pre-declared using i2c_register_board_info() is scanned, 157191ed5349SWolfram Sang * and the appropriate driver model device nodes are created. Otherwise, a 157291ed5349SWolfram Sang * negative errno value is returned. 157391ed5349SWolfram Sang */ 157491ed5349SWolfram Sang int i2c_add_numbered_adapter(struct i2c_adapter *adap) 157591ed5349SWolfram Sang { 157691ed5349SWolfram Sang if (adap->nr == -1) /* -1 means dynamically assign bus id */ 157791ed5349SWolfram Sang return i2c_add_adapter(adap); 157891ed5349SWolfram Sang 157991ed5349SWolfram Sang return __i2c_add_numbered_adapter(adap); 158091ed5349SWolfram Sang } 158191ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); 158291ed5349SWolfram Sang 158391ed5349SWolfram Sang static void i2c_do_del_adapter(struct i2c_driver *driver, 158491ed5349SWolfram Sang struct i2c_adapter *adapter) 158591ed5349SWolfram Sang { 158691ed5349SWolfram Sang struct i2c_client *client, *_n; 158791ed5349SWolfram Sang 158891ed5349SWolfram Sang /* Remove the devices we created ourselves as the result of hardware 158991ed5349SWolfram Sang * probing (using a driver's detect method) */ 159091ed5349SWolfram Sang list_for_each_entry_safe(client, _n, &driver->clients, detected) { 159191ed5349SWolfram Sang if (client->adapter == adapter) { 159291ed5349SWolfram Sang dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", 159391ed5349SWolfram Sang client->name, client->addr); 159491ed5349SWolfram Sang list_del(&client->detected); 159591ed5349SWolfram Sang i2c_unregister_device(client); 159691ed5349SWolfram Sang } 159791ed5349SWolfram Sang } 159891ed5349SWolfram Sang } 159991ed5349SWolfram Sang 160091ed5349SWolfram Sang static int __unregister_client(struct device *dev, void *dummy) 160191ed5349SWolfram Sang { 160291ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 160391ed5349SWolfram Sang if (client && strcmp(client->name, "dummy")) 160491ed5349SWolfram Sang i2c_unregister_device(client); 160591ed5349SWolfram Sang return 0; 160691ed5349SWolfram Sang } 160791ed5349SWolfram Sang 160891ed5349SWolfram Sang static int __unregister_dummy(struct device *dev, void *dummy) 160991ed5349SWolfram Sang { 161091ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 161191ed5349SWolfram Sang i2c_unregister_device(client); 161291ed5349SWolfram Sang return 0; 161391ed5349SWolfram Sang } 161491ed5349SWolfram Sang 161591ed5349SWolfram Sang static int __process_removed_adapter(struct device_driver *d, void *data) 161691ed5349SWolfram Sang { 161791ed5349SWolfram Sang i2c_do_del_adapter(to_i2c_driver(d), data); 161891ed5349SWolfram Sang return 0; 161991ed5349SWolfram Sang } 162091ed5349SWolfram Sang 162191ed5349SWolfram Sang /** 162291ed5349SWolfram Sang * i2c_del_adapter - unregister I2C adapter 162391ed5349SWolfram Sang * @adap: the adapter being unregistered 162491ed5349SWolfram Sang * Context: can sleep 162591ed5349SWolfram Sang * 162691ed5349SWolfram Sang * This unregisters an I2C adapter which was previously registered 162791ed5349SWolfram Sang * by @i2c_add_adapter or @i2c_add_numbered_adapter. 162891ed5349SWolfram Sang */ 162991ed5349SWolfram Sang void i2c_del_adapter(struct i2c_adapter *adap) 163091ed5349SWolfram Sang { 163191ed5349SWolfram Sang struct i2c_adapter *found; 163291ed5349SWolfram Sang struct i2c_client *client, *next; 163391ed5349SWolfram Sang 163491ed5349SWolfram Sang /* First make sure that this adapter was ever added */ 163591ed5349SWolfram Sang mutex_lock(&core_lock); 163691ed5349SWolfram Sang found = idr_find(&i2c_adapter_idr, adap->nr); 163791ed5349SWolfram Sang mutex_unlock(&core_lock); 163891ed5349SWolfram Sang if (found != adap) { 163991ed5349SWolfram Sang pr_debug("attempting to delete unregistered adapter [%s]\n", adap->name); 164091ed5349SWolfram Sang return; 164191ed5349SWolfram Sang } 164291ed5349SWolfram Sang 164391ed5349SWolfram Sang i2c_acpi_remove_space_handler(adap); 164491ed5349SWolfram Sang /* Tell drivers about this removal */ 164591ed5349SWolfram Sang mutex_lock(&core_lock); 164691ed5349SWolfram Sang bus_for_each_drv(&i2c_bus_type, NULL, adap, 164791ed5349SWolfram Sang __process_removed_adapter); 164891ed5349SWolfram Sang mutex_unlock(&core_lock); 164991ed5349SWolfram Sang 165091ed5349SWolfram Sang /* Remove devices instantiated from sysfs */ 165191ed5349SWolfram Sang mutex_lock_nested(&adap->userspace_clients_lock, 165291ed5349SWolfram Sang i2c_adapter_depth(adap)); 165391ed5349SWolfram Sang list_for_each_entry_safe(client, next, &adap->userspace_clients, 165491ed5349SWolfram Sang detected) { 165591ed5349SWolfram Sang dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, 165691ed5349SWolfram Sang client->addr); 165791ed5349SWolfram Sang list_del(&client->detected); 165891ed5349SWolfram Sang i2c_unregister_device(client); 165991ed5349SWolfram Sang } 166091ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 166191ed5349SWolfram Sang 166291ed5349SWolfram Sang /* Detach any active clients. This can't fail, thus we do not 166391ed5349SWolfram Sang * check the returned value. This is a two-pass process, because 166491ed5349SWolfram Sang * we can't remove the dummy devices during the first pass: they 166591ed5349SWolfram Sang * could have been instantiated by real devices wishing to clean 166691ed5349SWolfram Sang * them up properly, so we give them a chance to do that first. */ 166791ed5349SWolfram Sang device_for_each_child(&adap->dev, NULL, __unregister_client); 166891ed5349SWolfram Sang device_for_each_child(&adap->dev, NULL, __unregister_dummy); 166991ed5349SWolfram Sang 167091ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 167191ed5349SWolfram Sang class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, 167291ed5349SWolfram Sang adap->dev.parent); 167391ed5349SWolfram Sang #endif 167491ed5349SWolfram Sang 167591ed5349SWolfram Sang /* device name is gone after device_unregister */ 167691ed5349SWolfram Sang dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); 167791ed5349SWolfram Sang 167891ed5349SWolfram Sang pm_runtime_disable(&adap->dev); 167991ed5349SWolfram Sang 168091ed5349SWolfram Sang i2c_host_notify_irq_teardown(adap); 168191ed5349SWolfram Sang 168291ed5349SWolfram Sang /* wait until all references to the device are gone 168391ed5349SWolfram Sang * 168491ed5349SWolfram Sang * FIXME: This is old code and should ideally be replaced by an 168591ed5349SWolfram Sang * alternative which results in decoupling the lifetime of the struct 168691ed5349SWolfram Sang * device from the i2c_adapter, like spi or netdev do. Any solution 168791ed5349SWolfram Sang * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! 168891ed5349SWolfram Sang */ 168991ed5349SWolfram Sang init_completion(&adap->dev_released); 169091ed5349SWolfram Sang device_unregister(&adap->dev); 169191ed5349SWolfram Sang wait_for_completion(&adap->dev_released); 169291ed5349SWolfram Sang 169391ed5349SWolfram Sang /* free bus id */ 169491ed5349SWolfram Sang mutex_lock(&core_lock); 169591ed5349SWolfram Sang idr_remove(&i2c_adapter_idr, adap->nr); 169691ed5349SWolfram Sang mutex_unlock(&core_lock); 169791ed5349SWolfram Sang 169891ed5349SWolfram Sang /* Clear the device structure in case this adapter is ever going to be 169991ed5349SWolfram Sang added again */ 170091ed5349SWolfram Sang memset(&adap->dev, 0, sizeof(adap->dev)); 170191ed5349SWolfram Sang } 170291ed5349SWolfram Sang EXPORT_SYMBOL(i2c_del_adapter); 170391ed5349SWolfram Sang 1704def00b32SWolfram Sang static void i2c_parse_timing(struct device *dev, char *prop_name, u32 *cur_val_p, 1705def00b32SWolfram Sang u32 def_val, bool use_def) 1706def00b32SWolfram Sang { 1707def00b32SWolfram Sang int ret; 1708def00b32SWolfram Sang 1709def00b32SWolfram Sang ret = device_property_read_u32(dev, prop_name, cur_val_p); 1710def00b32SWolfram Sang if (ret && use_def) 1711def00b32SWolfram Sang *cur_val_p = def_val; 1712def00b32SWolfram Sang 1713def00b32SWolfram Sang dev_dbg(dev, "%s: %u\n", prop_name, *cur_val_p); 1714def00b32SWolfram Sang } 1715def00b32SWolfram Sang 171691ed5349SWolfram Sang /** 171791ed5349SWolfram Sang * i2c_parse_fw_timings - get I2C related timing parameters from firmware 171891ed5349SWolfram Sang * @dev: The device to scan for I2C timing properties 171991ed5349SWolfram Sang * @t: the i2c_timings struct to be filled with values 172091ed5349SWolfram Sang * @use_defaults: bool to use sane defaults derived from the I2C specification 1721263a5646SAndy Shevchenko * when properties are not found, otherwise don't update 172291ed5349SWolfram Sang * 172391ed5349SWolfram Sang * Scan the device for the generic I2C properties describing timing parameters 172491ed5349SWolfram Sang * for the signal and fill the given struct with the results. If a property was 172591ed5349SWolfram Sang * not found and use_defaults was true, then maximum timings are assumed which 172691ed5349SWolfram Sang * are derived from the I2C specification. If use_defaults is not used, the 1727263a5646SAndy Shevchenko * results will be as before, so drivers can apply their own defaults before 1728263a5646SAndy Shevchenko * calling this helper. The latter is mainly intended for avoiding regressions 1729263a5646SAndy Shevchenko * of existing drivers which want to switch to this function. New drivers 1730263a5646SAndy Shevchenko * almost always should use the defaults. 173191ed5349SWolfram Sang */ 173291ed5349SWolfram Sang void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) 173391ed5349SWolfram Sang { 1734def00b32SWolfram Sang bool u = use_defaults; 1735def00b32SWolfram Sang u32 d; 173691ed5349SWolfram Sang 1737def00b32SWolfram Sang i2c_parse_timing(dev, "clock-frequency", &t->bus_freq_hz, 1738def00b32SWolfram Sang I2C_MAX_STANDARD_MODE_FREQ, u); 173991ed5349SWolfram Sang 1740def00b32SWolfram Sang d = t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ ? 1000 : 1741def00b32SWolfram Sang t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; 1742def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns, d, u); 174391ed5349SWolfram Sang 1744def00b32SWolfram Sang d = t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; 1745def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns, d, u); 174691ed5349SWolfram Sang 1747def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-scl-internal-delay-ns", 1748def00b32SWolfram Sang &t->scl_int_delay_ns, 0, u); 1749def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns, 1750def00b32SWolfram Sang t->scl_fall_ns, u); 1751def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns, 0, u); 1752def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-digital-filter-width-ns", 1753def00b32SWolfram Sang &t->digital_filter_width_ns, 0, u); 1754def00b32SWolfram Sang i2c_parse_timing(dev, "i2c-analog-filter-cutoff-frequency", 1755def00b32SWolfram Sang &t->analog_filter_cutoff_freq_hz, 0, u); 175691ed5349SWolfram Sang } 175791ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); 175891ed5349SWolfram Sang 175991ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 176091ed5349SWolfram Sang 1761edd7a563SWolfram Sang int i2c_for_each_dev(void *data, int (*fn)(struct device *dev, void *data)) 176291ed5349SWolfram Sang { 176391ed5349SWolfram Sang int res; 176491ed5349SWolfram Sang 176591ed5349SWolfram Sang mutex_lock(&core_lock); 176691ed5349SWolfram Sang res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); 176791ed5349SWolfram Sang mutex_unlock(&core_lock); 176891ed5349SWolfram Sang 176991ed5349SWolfram Sang return res; 177091ed5349SWolfram Sang } 177191ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_for_each_dev); 177291ed5349SWolfram Sang 177391ed5349SWolfram Sang static int __process_new_driver(struct device *dev, void *data) 177491ed5349SWolfram Sang { 177591ed5349SWolfram Sang if (dev->type != &i2c_adapter_type) 177691ed5349SWolfram Sang return 0; 177791ed5349SWolfram Sang return i2c_do_add_adapter(data, to_i2c_adapter(dev)); 177891ed5349SWolfram Sang } 177991ed5349SWolfram Sang 178091ed5349SWolfram Sang /* 178191ed5349SWolfram Sang * An i2c_driver is used with one or more i2c_client (device) nodes to access 178291ed5349SWolfram Sang * i2c slave chips, on a bus instance associated with some i2c_adapter. 178391ed5349SWolfram Sang */ 178491ed5349SWolfram Sang 178591ed5349SWolfram Sang int i2c_register_driver(struct module *owner, struct i2c_driver *driver) 178691ed5349SWolfram Sang { 178791ed5349SWolfram Sang int res; 178891ed5349SWolfram Sang 178991ed5349SWolfram Sang /* Can't register until after driver model init */ 179091ed5349SWolfram Sang if (WARN_ON(!is_registered)) 179191ed5349SWolfram Sang return -EAGAIN; 179291ed5349SWolfram Sang 179391ed5349SWolfram Sang /* add the driver to the list of i2c drivers in the driver core */ 179491ed5349SWolfram Sang driver->driver.owner = owner; 179591ed5349SWolfram Sang driver->driver.bus = &i2c_bus_type; 179691ed5349SWolfram Sang INIT_LIST_HEAD(&driver->clients); 179791ed5349SWolfram Sang 179891ed5349SWolfram Sang /* When registration returns, the driver core 179991ed5349SWolfram Sang * will have called probe() for all matching-but-unbound devices. 180091ed5349SWolfram Sang */ 180191ed5349SWolfram Sang res = driver_register(&driver->driver); 180291ed5349SWolfram Sang if (res) 180391ed5349SWolfram Sang return res; 180491ed5349SWolfram Sang 180591ed5349SWolfram Sang pr_debug("driver [%s] registered\n", driver->driver.name); 180691ed5349SWolfram Sang 180791ed5349SWolfram Sang /* Walk the adapters that are already present */ 180891ed5349SWolfram Sang i2c_for_each_dev(driver, __process_new_driver); 180991ed5349SWolfram Sang 181091ed5349SWolfram Sang return 0; 181191ed5349SWolfram Sang } 181291ed5349SWolfram Sang EXPORT_SYMBOL(i2c_register_driver); 181391ed5349SWolfram Sang 181491ed5349SWolfram Sang static int __process_removed_driver(struct device *dev, void *data) 181591ed5349SWolfram Sang { 181691ed5349SWolfram Sang if (dev->type == &i2c_adapter_type) 181791ed5349SWolfram Sang i2c_do_del_adapter(data, to_i2c_adapter(dev)); 181891ed5349SWolfram Sang return 0; 181991ed5349SWolfram Sang } 182091ed5349SWolfram Sang 182191ed5349SWolfram Sang /** 182291ed5349SWolfram Sang * i2c_del_driver - unregister I2C driver 182391ed5349SWolfram Sang * @driver: the driver being unregistered 182491ed5349SWolfram Sang * Context: can sleep 182591ed5349SWolfram Sang */ 182691ed5349SWolfram Sang void i2c_del_driver(struct i2c_driver *driver) 182791ed5349SWolfram Sang { 182891ed5349SWolfram Sang i2c_for_each_dev(driver, __process_removed_driver); 182991ed5349SWolfram Sang 183091ed5349SWolfram Sang driver_unregister(&driver->driver); 183191ed5349SWolfram Sang pr_debug("driver [%s] unregistered\n", driver->driver.name); 183291ed5349SWolfram Sang } 183391ed5349SWolfram Sang EXPORT_SYMBOL(i2c_del_driver); 183491ed5349SWolfram Sang 183591ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 183691ed5349SWolfram Sang 183791ed5349SWolfram Sang struct i2c_cmd_arg { 183891ed5349SWolfram Sang unsigned cmd; 183991ed5349SWolfram Sang void *arg; 184091ed5349SWolfram Sang }; 184191ed5349SWolfram Sang 184291ed5349SWolfram Sang static int i2c_cmd(struct device *dev, void *_arg) 184391ed5349SWolfram Sang { 184491ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 184591ed5349SWolfram Sang struct i2c_cmd_arg *arg = _arg; 184691ed5349SWolfram Sang struct i2c_driver *driver; 184791ed5349SWolfram Sang 184891ed5349SWolfram Sang if (!client || !client->dev.driver) 184991ed5349SWolfram Sang return 0; 185091ed5349SWolfram Sang 185191ed5349SWolfram Sang driver = to_i2c_driver(client->dev.driver); 185291ed5349SWolfram Sang if (driver->command) 185391ed5349SWolfram Sang driver->command(client, arg->cmd, arg->arg); 185491ed5349SWolfram Sang return 0; 185591ed5349SWolfram Sang } 185691ed5349SWolfram Sang 185791ed5349SWolfram Sang void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) 185891ed5349SWolfram Sang { 185991ed5349SWolfram Sang struct i2c_cmd_arg cmd_arg; 186091ed5349SWolfram Sang 186191ed5349SWolfram Sang cmd_arg.cmd = cmd; 186291ed5349SWolfram Sang cmd_arg.arg = arg; 186391ed5349SWolfram Sang device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); 186491ed5349SWolfram Sang } 186591ed5349SWolfram Sang EXPORT_SYMBOL(i2c_clients_command); 186691ed5349SWolfram Sang 186791ed5349SWolfram Sang static int __init i2c_init(void) 186891ed5349SWolfram Sang { 186991ed5349SWolfram Sang int retval; 187091ed5349SWolfram Sang 187191ed5349SWolfram Sang retval = of_alias_get_highest_id("i2c"); 187291ed5349SWolfram Sang 187391ed5349SWolfram Sang down_write(&__i2c_board_lock); 187491ed5349SWolfram Sang if (retval >= __i2c_first_dynamic_bus_num) 187591ed5349SWolfram Sang __i2c_first_dynamic_bus_num = retval + 1; 187691ed5349SWolfram Sang up_write(&__i2c_board_lock); 187791ed5349SWolfram Sang 187891ed5349SWolfram Sang retval = bus_register(&i2c_bus_type); 187991ed5349SWolfram Sang if (retval) 188091ed5349SWolfram Sang return retval; 188191ed5349SWolfram Sang 188291ed5349SWolfram Sang is_registered = true; 188391ed5349SWolfram Sang 188491ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 188591ed5349SWolfram Sang i2c_adapter_compat_class = class_compat_register("i2c-adapter"); 188691ed5349SWolfram Sang if (!i2c_adapter_compat_class) { 188791ed5349SWolfram Sang retval = -ENOMEM; 188891ed5349SWolfram Sang goto bus_err; 188991ed5349SWolfram Sang } 189091ed5349SWolfram Sang #endif 189191ed5349SWolfram Sang retval = i2c_add_driver(&dummy_driver); 189291ed5349SWolfram Sang if (retval) 189391ed5349SWolfram Sang goto class_err; 189491ed5349SWolfram Sang 189591ed5349SWolfram Sang if (IS_ENABLED(CONFIG_OF_DYNAMIC)) 189691ed5349SWolfram Sang WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); 189791ed5349SWolfram Sang if (IS_ENABLED(CONFIG_ACPI)) 189891ed5349SWolfram Sang WARN_ON(acpi_reconfig_notifier_register(&i2c_acpi_notifier)); 189991ed5349SWolfram Sang 190091ed5349SWolfram Sang return 0; 190191ed5349SWolfram Sang 190291ed5349SWolfram Sang class_err: 190391ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 190491ed5349SWolfram Sang class_compat_unregister(i2c_adapter_compat_class); 190591ed5349SWolfram Sang bus_err: 190691ed5349SWolfram Sang #endif 190791ed5349SWolfram Sang is_registered = false; 190891ed5349SWolfram Sang bus_unregister(&i2c_bus_type); 190991ed5349SWolfram Sang return retval; 191091ed5349SWolfram Sang } 191191ed5349SWolfram Sang 191291ed5349SWolfram Sang static void __exit i2c_exit(void) 191391ed5349SWolfram Sang { 191491ed5349SWolfram Sang if (IS_ENABLED(CONFIG_ACPI)) 191591ed5349SWolfram Sang WARN_ON(acpi_reconfig_notifier_unregister(&i2c_acpi_notifier)); 191691ed5349SWolfram Sang if (IS_ENABLED(CONFIG_OF_DYNAMIC)) 191791ed5349SWolfram Sang WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); 191891ed5349SWolfram Sang i2c_del_driver(&dummy_driver); 191991ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 192091ed5349SWolfram Sang class_compat_unregister(i2c_adapter_compat_class); 192191ed5349SWolfram Sang #endif 192291ed5349SWolfram Sang bus_unregister(&i2c_bus_type); 192391ed5349SWolfram Sang tracepoint_synchronize_unregister(); 192491ed5349SWolfram Sang } 192591ed5349SWolfram Sang 192691ed5349SWolfram Sang /* We must initialize early, because some subsystems register i2c drivers 192791ed5349SWolfram Sang * in subsys_initcall() code, but are linked (and initialized) before i2c. 192891ed5349SWolfram Sang */ 192991ed5349SWolfram Sang postcore_initcall(i2c_init); 193091ed5349SWolfram Sang module_exit(i2c_exit); 193191ed5349SWolfram Sang 193291ed5349SWolfram Sang /* ---------------------------------------------------- 193391ed5349SWolfram Sang * the functional interface to the i2c busses. 193491ed5349SWolfram Sang * ---------------------------------------------------- 193591ed5349SWolfram Sang */ 193691ed5349SWolfram Sang 193791ed5349SWolfram Sang /* Check if val is exceeding the quirk IFF quirk is non 0 */ 193891ed5349SWolfram Sang #define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) 193991ed5349SWolfram Sang 194091ed5349SWolfram Sang static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) 194191ed5349SWolfram Sang { 194291ed5349SWolfram Sang dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", 194391ed5349SWolfram Sang err_msg, msg->addr, msg->len, 194491ed5349SWolfram Sang msg->flags & I2C_M_RD ? "read" : "write"); 194591ed5349SWolfram Sang return -EOPNOTSUPP; 194691ed5349SWolfram Sang } 194791ed5349SWolfram Sang 194891ed5349SWolfram Sang static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 194991ed5349SWolfram Sang { 195091ed5349SWolfram Sang const struct i2c_adapter_quirks *q = adap->quirks; 195191ed5349SWolfram Sang int max_num = q->max_num_msgs, i; 195291ed5349SWolfram Sang bool do_len_check = true; 195391ed5349SWolfram Sang 195491ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB) { 195591ed5349SWolfram Sang max_num = 2; 195691ed5349SWolfram Sang 195791ed5349SWolfram Sang /* special checks for combined messages */ 195891ed5349SWolfram Sang if (num == 2) { 195991ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) 196091ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); 196191ed5349SWolfram Sang 196291ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) 196391ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); 196491ed5349SWolfram Sang 196591ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) 196691ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); 196791ed5349SWolfram Sang 196891ed5349SWolfram Sang if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) 196991ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "msg too long"); 197091ed5349SWolfram Sang 197191ed5349SWolfram Sang if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) 197291ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[1], "msg too long"); 197391ed5349SWolfram Sang 197491ed5349SWolfram Sang do_len_check = false; 197591ed5349SWolfram Sang } 197691ed5349SWolfram Sang } 197791ed5349SWolfram Sang 197891ed5349SWolfram Sang if (i2c_quirk_exceeded(num, max_num)) 197991ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "too many messages"); 198091ed5349SWolfram Sang 198191ed5349SWolfram Sang for (i = 0; i < num; i++) { 198291ed5349SWolfram Sang u16 len = msgs[i].len; 198391ed5349SWolfram Sang 198491ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) { 198591ed5349SWolfram Sang if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) 198691ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[i], "msg too long"); 1987d9cfe2ceSWolfram Sang 1988d9cfe2ceSWolfram Sang if (q->flags & I2C_AQ_NO_ZERO_LEN_READ && len == 0) 1989d9cfe2ceSWolfram Sang return i2c_quirk_error(adap, &msgs[i], "no zero length"); 199091ed5349SWolfram Sang } else { 199191ed5349SWolfram Sang if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) 199291ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[i], "msg too long"); 1993d9cfe2ceSWolfram Sang 1994d9cfe2ceSWolfram Sang if (q->flags & I2C_AQ_NO_ZERO_LEN_WRITE && len == 0) 1995d9cfe2ceSWolfram Sang return i2c_quirk_error(adap, &msgs[i], "no zero length"); 199691ed5349SWolfram Sang } 199791ed5349SWolfram Sang } 199891ed5349SWolfram Sang 199991ed5349SWolfram Sang return 0; 200091ed5349SWolfram Sang } 200191ed5349SWolfram Sang 200291ed5349SWolfram Sang /** 200391ed5349SWolfram Sang * __i2c_transfer - unlocked flavor of i2c_transfer 200491ed5349SWolfram Sang * @adap: Handle to I2C bus 200591ed5349SWolfram Sang * @msgs: One or more messages to execute before STOP is issued to 200691ed5349SWolfram Sang * terminate the operation; each message begins with a START. 200791ed5349SWolfram Sang * @num: Number of messages to be executed. 200891ed5349SWolfram Sang * 200991ed5349SWolfram Sang * Returns negative errno, else the number of messages executed. 201091ed5349SWolfram Sang * 201191ed5349SWolfram Sang * Adapter lock must be held when calling this function. No debug logging 201291ed5349SWolfram Sang * takes place. adap->algo->master_xfer existence isn't checked. 201391ed5349SWolfram Sang */ 201491ed5349SWolfram Sang int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 201591ed5349SWolfram Sang { 201691ed5349SWolfram Sang unsigned long orig_jiffies; 201791ed5349SWolfram Sang int ret, try; 201891ed5349SWolfram Sang 20191eace834SArd Biesheuvel if (WARN_ON(!msgs || num < 1)) 20201eace834SArd Biesheuvel return -EINVAL; 20215d756112SWolfram Sang 20225d756112SWolfram Sang ret = __i2c_check_suspended(adap); 20235d756112SWolfram Sang if (ret) 20245d756112SWolfram Sang return ret; 20251eace834SArd Biesheuvel 202691ed5349SWolfram Sang if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) 202791ed5349SWolfram Sang return -EOPNOTSUPP; 202891ed5349SWolfram Sang 202950888b01SDavidlohr Bueso /* 203050888b01SDavidlohr Bueso * i2c_trace_msg_key gets enabled when tracepoint i2c_transfer gets 203191ed5349SWolfram Sang * enabled. This is an efficient way of keeping the for-loop from 203291ed5349SWolfram Sang * being executed when not needed. 203391ed5349SWolfram Sang */ 203450888b01SDavidlohr Bueso if (static_branch_unlikely(&i2c_trace_msg_key)) { 203591ed5349SWolfram Sang int i; 203691ed5349SWolfram Sang for (i = 0; i < num; i++) 203791ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) 203891ed5349SWolfram Sang trace_i2c_read(adap, &msgs[i], i); 203991ed5349SWolfram Sang else 204091ed5349SWolfram Sang trace_i2c_write(adap, &msgs[i], i); 204191ed5349SWolfram Sang } 204291ed5349SWolfram Sang 204391ed5349SWolfram Sang /* Retry automatically on arbitration loss */ 204491ed5349SWolfram Sang orig_jiffies = jiffies; 204591ed5349SWolfram Sang for (ret = 0, try = 0; try <= adap->retries; try++) { 204663b96983SWolfram Sang if (i2c_in_atomic_xfer_mode() && adap->algo->master_xfer_atomic) 204763b96983SWolfram Sang ret = adap->algo->master_xfer_atomic(adap, msgs, num); 204863b96983SWolfram Sang else 204991ed5349SWolfram Sang ret = adap->algo->master_xfer(adap, msgs, num); 205063b96983SWolfram Sang 205191ed5349SWolfram Sang if (ret != -EAGAIN) 205291ed5349SWolfram Sang break; 205391ed5349SWolfram Sang if (time_after(jiffies, orig_jiffies + adap->timeout)) 205491ed5349SWolfram Sang break; 205591ed5349SWolfram Sang } 205691ed5349SWolfram Sang 205750888b01SDavidlohr Bueso if (static_branch_unlikely(&i2c_trace_msg_key)) { 205891ed5349SWolfram Sang int i; 205991ed5349SWolfram Sang for (i = 0; i < ret; i++) 206091ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) 206191ed5349SWolfram Sang trace_i2c_reply(adap, &msgs[i], i); 20624a3f7691SAhbong Chang trace_i2c_result(adap, num, ret); 206391ed5349SWolfram Sang } 206491ed5349SWolfram Sang 206591ed5349SWolfram Sang return ret; 206691ed5349SWolfram Sang } 206791ed5349SWolfram Sang EXPORT_SYMBOL(__i2c_transfer); 206891ed5349SWolfram Sang 206991ed5349SWolfram Sang /** 207091ed5349SWolfram Sang * i2c_transfer - execute a single or combined I2C message 207191ed5349SWolfram Sang * @adap: Handle to I2C bus 207291ed5349SWolfram Sang * @msgs: One or more messages to execute before STOP is issued to 207391ed5349SWolfram Sang * terminate the operation; each message begins with a START. 207491ed5349SWolfram Sang * @num: Number of messages to be executed. 207591ed5349SWolfram Sang * 207691ed5349SWolfram Sang * Returns negative errno, else the number of messages executed. 207791ed5349SWolfram Sang * 207891ed5349SWolfram Sang * Note that there is no requirement that each message be sent to 207991ed5349SWolfram Sang * the same slave address, although that is the most common model. 208091ed5349SWolfram Sang */ 208191ed5349SWolfram Sang int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 208291ed5349SWolfram Sang { 208391ed5349SWolfram Sang int ret; 208491ed5349SWolfram Sang 2085cc52612eSWolfram Sang if (!adap->algo->master_xfer) { 2086cc52612eSWolfram Sang dev_dbg(&adap->dev, "I2C level transfers not supported\n"); 2087cc52612eSWolfram Sang return -EOPNOTSUPP; 2088cc52612eSWolfram Sang } 2089cc52612eSWolfram Sang 209091ed5349SWolfram Sang /* REVISIT the fault reporting model here is weak: 209191ed5349SWolfram Sang * 209291ed5349SWolfram Sang * - When we get an error after receiving N bytes from a slave, 209391ed5349SWolfram Sang * there is no way to report "N". 209491ed5349SWolfram Sang * 209591ed5349SWolfram Sang * - When we get a NAK after transmitting N bytes to a slave, 209691ed5349SWolfram Sang * there is no way to report "N" ... or to let the master 209791ed5349SWolfram Sang * continue executing the rest of this combined message, if 209891ed5349SWolfram Sang * that's the appropriate response. 209991ed5349SWolfram Sang * 210091ed5349SWolfram Sang * - When for example "num" is two and we successfully complete 210191ed5349SWolfram Sang * the first message but get an error part way through the 210291ed5349SWolfram Sang * second, it's unclear whether that should be reported as 210391ed5349SWolfram Sang * one (discarding status on the second message) or errno 210491ed5349SWolfram Sang * (discarding status on the first one). 210591ed5349SWolfram Sang */ 210683c42212SWolfram Sang ret = __i2c_lock_bus_helper(adap); 210783c42212SWolfram Sang if (ret) 210883c42212SWolfram Sang return ret; 210991ed5349SWolfram Sang 211091ed5349SWolfram Sang ret = __i2c_transfer(adap, msgs, num); 211191ed5349SWolfram Sang i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); 211291ed5349SWolfram Sang 211391ed5349SWolfram Sang return ret; 211491ed5349SWolfram Sang } 211591ed5349SWolfram Sang EXPORT_SYMBOL(i2c_transfer); 211691ed5349SWolfram Sang 211791ed5349SWolfram Sang /** 21188a91732bSWolfram Sang * i2c_transfer_buffer_flags - issue a single I2C message transferring data 21198a91732bSWolfram Sang * to/from a buffer 212091ed5349SWolfram Sang * @client: Handle to slave device 21218a91732bSWolfram Sang * @buf: Where the data is stored 21228a91732bSWolfram Sang * @count: How many bytes to transfer, must be less than 64k since msg.len is u16 21238a91732bSWolfram Sang * @flags: The flags to be used for the message, e.g. I2C_M_RD for reads 212491ed5349SWolfram Sang * 21258a91732bSWolfram Sang * Returns negative errno, or else the number of bytes transferred. 212691ed5349SWolfram Sang */ 21278a91732bSWolfram Sang int i2c_transfer_buffer_flags(const struct i2c_client *client, char *buf, 21288a91732bSWolfram Sang int count, u16 flags) 212991ed5349SWolfram Sang { 213091ed5349SWolfram Sang int ret; 21318a91732bSWolfram Sang struct i2c_msg msg = { 21328a91732bSWolfram Sang .addr = client->addr, 21338a91732bSWolfram Sang .flags = flags | (client->flags & I2C_M_TEN), 21348a91732bSWolfram Sang .len = count, 21358a91732bSWolfram Sang .buf = buf, 21368a91732bSWolfram Sang }; 213791ed5349SWolfram Sang 21388a91732bSWolfram Sang ret = i2c_transfer(client->adapter, &msg, 1); 213991ed5349SWolfram Sang 214091ed5349SWolfram Sang /* 21418a91732bSWolfram Sang * If everything went ok (i.e. 1 msg transferred), return #bytes 21428a91732bSWolfram Sang * transferred, else error code. 214391ed5349SWolfram Sang */ 214491ed5349SWolfram Sang return (ret == 1) ? count : ret; 214591ed5349SWolfram Sang } 21468a91732bSWolfram Sang EXPORT_SYMBOL(i2c_transfer_buffer_flags); 214791ed5349SWolfram Sang 2148dde67eb1SPeter Rosin /** 2149dde67eb1SPeter Rosin * i2c_get_device_id - get manufacturer, part id and die revision of a device 2150dde67eb1SPeter Rosin * @client: The device to query 2151dde67eb1SPeter Rosin * @id: The queried information 2152dde67eb1SPeter Rosin * 2153dde67eb1SPeter Rosin * Returns negative errno on error, zero on success. 2154dde67eb1SPeter Rosin */ 2155dde67eb1SPeter Rosin int i2c_get_device_id(const struct i2c_client *client, 2156dde67eb1SPeter Rosin struct i2c_device_identity *id) 2157dde67eb1SPeter Rosin { 2158dde67eb1SPeter Rosin struct i2c_adapter *adap = client->adapter; 2159dde67eb1SPeter Rosin union i2c_smbus_data raw_id; 2160dde67eb1SPeter Rosin int ret; 2161dde67eb1SPeter Rosin 2162dde67eb1SPeter Rosin if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) 2163dde67eb1SPeter Rosin return -EOPNOTSUPP; 2164dde67eb1SPeter Rosin 2165dde67eb1SPeter Rosin raw_id.block[0] = 3; 2166dde67eb1SPeter Rosin ret = i2c_smbus_xfer(adap, I2C_ADDR_DEVICE_ID, 0, 2167dde67eb1SPeter Rosin I2C_SMBUS_READ, client->addr << 1, 2168dde67eb1SPeter Rosin I2C_SMBUS_I2C_BLOCK_DATA, &raw_id); 2169dde67eb1SPeter Rosin if (ret) 2170dde67eb1SPeter Rosin return ret; 2171dde67eb1SPeter Rosin 2172dde67eb1SPeter Rosin id->manufacturer_id = (raw_id.block[1] << 4) | (raw_id.block[2] >> 4); 2173dde67eb1SPeter Rosin id->part_id = ((raw_id.block[2] & 0xf) << 5) | (raw_id.block[3] >> 3); 2174dde67eb1SPeter Rosin id->die_revision = raw_id.block[3] & 0x7; 2175dde67eb1SPeter Rosin return 0; 2176dde67eb1SPeter Rosin } 2177dde67eb1SPeter Rosin EXPORT_SYMBOL_GPL(i2c_get_device_id); 2178dde67eb1SPeter Rosin 217991ed5349SWolfram Sang /* ---------------------------------------------------- 218091ed5349SWolfram Sang * the i2c address scanning function 218191ed5349SWolfram Sang * Will not work for 10-bit addresses! 218291ed5349SWolfram Sang * ---------------------------------------------------- 218391ed5349SWolfram Sang */ 218491ed5349SWolfram Sang 218591ed5349SWolfram Sang /* 218691ed5349SWolfram Sang * Legacy default probe function, mostly relevant for SMBus. The default 218791ed5349SWolfram Sang * probe method is a quick write, but it is known to corrupt the 24RF08 218891ed5349SWolfram Sang * EEPROMs due to a state machine bug, and could also irreversibly 218991ed5349SWolfram Sang * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, 219091ed5349SWolfram Sang * we use a short byte read instead. Also, some bus drivers don't implement 219191ed5349SWolfram Sang * quick write, so we fallback to a byte read in that case too. 219291ed5349SWolfram Sang * On x86, there is another special case for FSC hardware monitoring chips, 219391ed5349SWolfram Sang * which want regular byte reads (address 0x73.) Fortunately, these are the 219491ed5349SWolfram Sang * only known chips using this I2C address on PC hardware. 219591ed5349SWolfram Sang * Returns 1 if probe succeeded, 0 if not. 219691ed5349SWolfram Sang */ 219791ed5349SWolfram Sang static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) 219891ed5349SWolfram Sang { 219991ed5349SWolfram Sang int err; 220091ed5349SWolfram Sang union i2c_smbus_data dummy; 220191ed5349SWolfram Sang 220291ed5349SWolfram Sang #ifdef CONFIG_X86 220391ed5349SWolfram Sang if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) 220491ed5349SWolfram Sang && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) 220591ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 220691ed5349SWolfram Sang I2C_SMBUS_BYTE_DATA, &dummy); 220791ed5349SWolfram Sang else 220891ed5349SWolfram Sang #endif 220991ed5349SWolfram Sang if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) 221091ed5349SWolfram Sang && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) 221191ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, 221291ed5349SWolfram Sang I2C_SMBUS_QUICK, NULL); 221391ed5349SWolfram Sang else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) 221491ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 221591ed5349SWolfram Sang I2C_SMBUS_BYTE, &dummy); 221691ed5349SWolfram Sang else { 221791ed5349SWolfram Sang dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", 221891ed5349SWolfram Sang addr); 221991ed5349SWolfram Sang err = -EOPNOTSUPP; 222091ed5349SWolfram Sang } 222191ed5349SWolfram Sang 222291ed5349SWolfram Sang return err >= 0; 222391ed5349SWolfram Sang } 222491ed5349SWolfram Sang 222591ed5349SWolfram Sang static int i2c_detect_address(struct i2c_client *temp_client, 222691ed5349SWolfram Sang struct i2c_driver *driver) 222791ed5349SWolfram Sang { 222891ed5349SWolfram Sang struct i2c_board_info info; 222991ed5349SWolfram Sang struct i2c_adapter *adapter = temp_client->adapter; 223091ed5349SWolfram Sang int addr = temp_client->addr; 223191ed5349SWolfram Sang int err; 223291ed5349SWolfram Sang 223391ed5349SWolfram Sang /* Make sure the address is valid */ 223491ed5349SWolfram Sang err = i2c_check_7bit_addr_validity_strict(addr); 223591ed5349SWolfram Sang if (err) { 223691ed5349SWolfram Sang dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", 223791ed5349SWolfram Sang addr); 223891ed5349SWolfram Sang return err; 223991ed5349SWolfram Sang } 224091ed5349SWolfram Sang 224191ed5349SWolfram Sang /* Skip if already in use (7 bit, no need to encode flags) */ 224291ed5349SWolfram Sang if (i2c_check_addr_busy(adapter, addr)) 224391ed5349SWolfram Sang return 0; 224491ed5349SWolfram Sang 224591ed5349SWolfram Sang /* Make sure there is something at this address */ 224691ed5349SWolfram Sang if (!i2c_default_probe(adapter, addr)) 224791ed5349SWolfram Sang return 0; 224891ed5349SWolfram Sang 224991ed5349SWolfram Sang /* Finally call the custom detection function */ 225091ed5349SWolfram Sang memset(&info, 0, sizeof(struct i2c_board_info)); 225191ed5349SWolfram Sang info.addr = addr; 225291ed5349SWolfram Sang err = driver->detect(temp_client, &info); 225391ed5349SWolfram Sang if (err) { 225491ed5349SWolfram Sang /* -ENODEV is returned if the detection fails. We catch it 225591ed5349SWolfram Sang here as this isn't an error. */ 225691ed5349SWolfram Sang return err == -ENODEV ? 0 : err; 225791ed5349SWolfram Sang } 225891ed5349SWolfram Sang 225991ed5349SWolfram Sang /* Consistency check */ 226091ed5349SWolfram Sang if (info.type[0] == '\0') { 226191ed5349SWolfram Sang dev_err(&adapter->dev, 226291ed5349SWolfram Sang "%s detection function provided no name for 0x%x\n", 226391ed5349SWolfram Sang driver->driver.name, addr); 226491ed5349SWolfram Sang } else { 226591ed5349SWolfram Sang struct i2c_client *client; 226691ed5349SWolfram Sang 226791ed5349SWolfram Sang /* Detection succeeded, instantiate the device */ 226891ed5349SWolfram Sang if (adapter->class & I2C_CLASS_DEPRECATED) 226991ed5349SWolfram Sang dev_warn(&adapter->dev, 227091ed5349SWolfram Sang "This adapter will soon drop class based instantiation of devices. " 227191ed5349SWolfram Sang "Please make sure client 0x%02x gets instantiated by other means. " 2272ccf988b6SMauro Carvalho Chehab "Check 'Documentation/i2c/instantiating-devices.rst' for details.\n", 227391ed5349SWolfram Sang info.addr); 227491ed5349SWolfram Sang 227591ed5349SWolfram Sang dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", 227691ed5349SWolfram Sang info.type, info.addr); 227787e07437SWolfram Sang client = i2c_new_client_device(adapter, &info); 227887e07437SWolfram Sang if (!IS_ERR(client)) 227991ed5349SWolfram Sang list_add_tail(&client->detected, &driver->clients); 228091ed5349SWolfram Sang else 228191ed5349SWolfram Sang dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", 228291ed5349SWolfram Sang info.type, info.addr); 228391ed5349SWolfram Sang } 228491ed5349SWolfram Sang return 0; 228591ed5349SWolfram Sang } 228691ed5349SWolfram Sang 228791ed5349SWolfram Sang static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) 228891ed5349SWolfram Sang { 228991ed5349SWolfram Sang const unsigned short *address_list; 229091ed5349SWolfram Sang struct i2c_client *temp_client; 229191ed5349SWolfram Sang int i, err = 0; 229291ed5349SWolfram Sang 229391ed5349SWolfram Sang address_list = driver->address_list; 229491ed5349SWolfram Sang if (!driver->detect || !address_list) 229591ed5349SWolfram Sang return 0; 229691ed5349SWolfram Sang 229791ed5349SWolfram Sang /* Warn that the adapter lost class based instantiation */ 229891ed5349SWolfram Sang if (adapter->class == I2C_CLASS_DEPRECATED) { 229991ed5349SWolfram Sang dev_dbg(&adapter->dev, 230091ed5349SWolfram Sang "This adapter dropped support for I2C classes and won't auto-detect %s devices anymore. " 2301ccf988b6SMauro Carvalho Chehab "If you need it, check 'Documentation/i2c/instantiating-devices.rst' for alternatives.\n", 230291ed5349SWolfram Sang driver->driver.name); 230391ed5349SWolfram Sang return 0; 230491ed5349SWolfram Sang } 230591ed5349SWolfram Sang 230691ed5349SWolfram Sang /* Stop here if the classes do not match */ 230791ed5349SWolfram Sang if (!(adapter->class & driver->class)) 230891ed5349SWolfram Sang return 0; 230991ed5349SWolfram Sang 231091ed5349SWolfram Sang /* Set up a temporary client to help detect callback */ 231191ed5349SWolfram Sang temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); 231291ed5349SWolfram Sang if (!temp_client) 231391ed5349SWolfram Sang return -ENOMEM; 231491ed5349SWolfram Sang temp_client->adapter = adapter; 231591ed5349SWolfram Sang 231691ed5349SWolfram Sang for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { 231791ed5349SWolfram Sang dev_dbg(&adapter->dev, 231891ed5349SWolfram Sang "found normal entry for adapter %d, addr 0x%02x\n", 2319dd4f2ca9SWolfram Sang i2c_adapter_id(adapter), address_list[i]); 232091ed5349SWolfram Sang temp_client->addr = address_list[i]; 232191ed5349SWolfram Sang err = i2c_detect_address(temp_client, driver); 232291ed5349SWolfram Sang if (unlikely(err)) 232391ed5349SWolfram Sang break; 232491ed5349SWolfram Sang } 232591ed5349SWolfram Sang 232691ed5349SWolfram Sang kfree(temp_client); 232791ed5349SWolfram Sang return err; 232891ed5349SWolfram Sang } 232991ed5349SWolfram Sang 233091ed5349SWolfram Sang int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) 233191ed5349SWolfram Sang { 233291ed5349SWolfram Sang return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 233391ed5349SWolfram Sang I2C_SMBUS_QUICK, NULL) >= 0; 233491ed5349SWolfram Sang } 233591ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); 233691ed5349SWolfram Sang 233791ed5349SWolfram Sang struct i2c_client * 2338c1d08475SWolfram Sang i2c_new_scanned_device(struct i2c_adapter *adap, 233991ed5349SWolfram Sang struct i2c_board_info *info, 234091ed5349SWolfram Sang unsigned short const *addr_list, 2341edd7a563SWolfram Sang int (*probe)(struct i2c_adapter *adap, unsigned short addr)) 234291ed5349SWolfram Sang { 234391ed5349SWolfram Sang int i; 234491ed5349SWolfram Sang 234591ed5349SWolfram Sang if (!probe) 234691ed5349SWolfram Sang probe = i2c_default_probe; 234791ed5349SWolfram Sang 234891ed5349SWolfram Sang for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { 234991ed5349SWolfram Sang /* Check address validity */ 235091ed5349SWolfram Sang if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { 235191ed5349SWolfram Sang dev_warn(&adap->dev, "Invalid 7-bit address 0x%02x\n", 235291ed5349SWolfram Sang addr_list[i]); 235391ed5349SWolfram Sang continue; 235491ed5349SWolfram Sang } 235591ed5349SWolfram Sang 235691ed5349SWolfram Sang /* Check address availability (7 bit, no need to encode flags) */ 235791ed5349SWolfram Sang if (i2c_check_addr_busy(adap, addr_list[i])) { 235891ed5349SWolfram Sang dev_dbg(&adap->dev, 235991ed5349SWolfram Sang "Address 0x%02x already in use, not probing\n", 236091ed5349SWolfram Sang addr_list[i]); 236191ed5349SWolfram Sang continue; 236291ed5349SWolfram Sang } 236391ed5349SWolfram Sang 236491ed5349SWolfram Sang /* Test address responsiveness */ 236591ed5349SWolfram Sang if (probe(adap, addr_list[i])) 236691ed5349SWolfram Sang break; 236791ed5349SWolfram Sang } 236891ed5349SWolfram Sang 236991ed5349SWolfram Sang if (addr_list[i] == I2C_CLIENT_END) { 237091ed5349SWolfram Sang dev_dbg(&adap->dev, "Probing failed, no device found\n"); 2371c1d08475SWolfram Sang return ERR_PTR(-ENODEV); 237291ed5349SWolfram Sang } 237391ed5349SWolfram Sang 237491ed5349SWolfram Sang info->addr = addr_list[i]; 2375c1d08475SWolfram Sang return i2c_new_client_device(adap, info); 2376c1d08475SWolfram Sang } 2377c1d08475SWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_scanned_device); 2378c1d08475SWolfram Sang 237991ed5349SWolfram Sang struct i2c_adapter *i2c_get_adapter(int nr) 238091ed5349SWolfram Sang { 238191ed5349SWolfram Sang struct i2c_adapter *adapter; 238291ed5349SWolfram Sang 238391ed5349SWolfram Sang mutex_lock(&core_lock); 238491ed5349SWolfram Sang adapter = idr_find(&i2c_adapter_idr, nr); 238591ed5349SWolfram Sang if (!adapter) 238691ed5349SWolfram Sang goto exit; 238791ed5349SWolfram Sang 238891ed5349SWolfram Sang if (try_module_get(adapter->owner)) 238991ed5349SWolfram Sang get_device(&adapter->dev); 239091ed5349SWolfram Sang else 239191ed5349SWolfram Sang adapter = NULL; 239291ed5349SWolfram Sang 239391ed5349SWolfram Sang exit: 239491ed5349SWolfram Sang mutex_unlock(&core_lock); 239591ed5349SWolfram Sang return adapter; 239691ed5349SWolfram Sang } 239791ed5349SWolfram Sang EXPORT_SYMBOL(i2c_get_adapter); 239891ed5349SWolfram Sang 239991ed5349SWolfram Sang void i2c_put_adapter(struct i2c_adapter *adap) 240091ed5349SWolfram Sang { 240191ed5349SWolfram Sang if (!adap) 240291ed5349SWolfram Sang return; 240391ed5349SWolfram Sang 240491ed5349SWolfram Sang put_device(&adap->dev); 240591ed5349SWolfram Sang module_put(adap->owner); 240691ed5349SWolfram Sang } 240791ed5349SWolfram Sang EXPORT_SYMBOL(i2c_put_adapter); 240891ed5349SWolfram Sang 2409e94bc5d1SWolfram Sang /** 2410e94bc5d1SWolfram Sang * i2c_get_dma_safe_msg_buf() - get a DMA safe buffer for the given i2c_msg 2411e94bc5d1SWolfram Sang * @msg: the message to be checked 2412bf263c35SWolfram Sang * @threshold: the minimum number of bytes for which using DMA makes sense. 2413bf263c35SWolfram Sang * Should at least be 1. 2414e94bc5d1SWolfram Sang * 2415e94bc5d1SWolfram Sang * Return: NULL if a DMA safe buffer was not obtained. Use msg->buf with PIO. 2416e94bc5d1SWolfram Sang * Or a valid pointer to be used with DMA. After use, release it by 241734d1b82cSStephen Boyd * calling i2c_put_dma_safe_msg_buf(). 2418e94bc5d1SWolfram Sang * 2419e94bc5d1SWolfram Sang * This function must only be called from process context! 2420e94bc5d1SWolfram Sang */ 2421e94bc5d1SWolfram Sang u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold) 2422e94bc5d1SWolfram Sang { 2423bf263c35SWolfram Sang /* also skip 0-length msgs for bogus thresholds of 0 */ 2424bf263c35SWolfram Sang if (!threshold) 2425bf263c35SWolfram Sang pr_debug("DMA buffer for addr=0x%02x with length 0 is bogus\n", 2426bf263c35SWolfram Sang msg->addr); 2427bf263c35SWolfram Sang if (msg->len < threshold || msg->len == 0) 2428e94bc5d1SWolfram Sang return NULL; 2429e94bc5d1SWolfram Sang 2430e94bc5d1SWolfram Sang if (msg->flags & I2C_M_DMA_SAFE) 2431e94bc5d1SWolfram Sang return msg->buf; 2432e94bc5d1SWolfram Sang 2433e94bc5d1SWolfram Sang pr_debug("using bounce buffer for addr=0x%02x, len=%d\n", 2434e94bc5d1SWolfram Sang msg->addr, msg->len); 2435e94bc5d1SWolfram Sang 2436e94bc5d1SWolfram Sang if (msg->flags & I2C_M_RD) 2437e94bc5d1SWolfram Sang return kzalloc(msg->len, GFP_KERNEL); 2438e94bc5d1SWolfram Sang else 2439e94bc5d1SWolfram Sang return kmemdup(msg->buf, msg->len, GFP_KERNEL); 2440e94bc5d1SWolfram Sang } 2441e94bc5d1SWolfram Sang EXPORT_SYMBOL_GPL(i2c_get_dma_safe_msg_buf); 2442e94bc5d1SWolfram Sang 2443e94bc5d1SWolfram Sang /** 244482fe39a6SWolfram Sang * i2c_put_dma_safe_msg_buf - release DMA safe buffer and sync with i2c_msg 2445e94bc5d1SWolfram Sang * @buf: the buffer obtained from i2c_get_dma_safe_msg_buf(). May be NULL. 244682fe39a6SWolfram Sang * @msg: the message which the buffer corresponds to 244782fe39a6SWolfram Sang * @xferred: bool saying if the message was transferred 2448e94bc5d1SWolfram Sang */ 244982fe39a6SWolfram Sang void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred) 2450e94bc5d1SWolfram Sang { 2451e94bc5d1SWolfram Sang if (!buf || buf == msg->buf) 2452e94bc5d1SWolfram Sang return; 2453e94bc5d1SWolfram Sang 245482fe39a6SWolfram Sang if (xferred && msg->flags & I2C_M_RD) 2455e94bc5d1SWolfram Sang memcpy(msg->buf, buf, msg->len); 2456e94bc5d1SWolfram Sang 2457e94bc5d1SWolfram Sang kfree(buf); 2458e94bc5d1SWolfram Sang } 245982fe39a6SWolfram Sang EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf); 2460e94bc5d1SWolfram Sang 246191ed5349SWolfram Sang MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); 246291ed5349SWolfram Sang MODULE_DESCRIPTION("I2C-Bus main module"); 246391ed5349SWolfram Sang MODULE_LICENSE("GPL"); 2464