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 * 1061e3d0f7SWolfram Sang * Copyright (C) 2013-2017 Wolfram Sang <wsa@the-dreams.de> 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> 3591ed5349SWolfram Sang #include <linux/pm_domain.h> 3691ed5349SWolfram Sang #include <linux/pm_runtime.h> 3791ed5349SWolfram Sang #include <linux/pm_wakeirq.h> 3891ed5349SWolfram Sang #include <linux/property.h> 3991ed5349SWolfram Sang #include <linux/rwsem.h> 4091ed5349SWolfram Sang #include <linux/slab.h> 4191ed5349SWolfram Sang 4291ed5349SWolfram Sang #include "i2c-core.h" 4391ed5349SWolfram Sang 4491ed5349SWolfram Sang #define CREATE_TRACE_POINTS 4591ed5349SWolfram Sang #include <trace/events/i2c.h> 4691ed5349SWolfram Sang 4791ed5349SWolfram Sang #define I2C_ADDR_OFFSET_TEN_BIT 0xa000 4891ed5349SWolfram Sang #define I2C_ADDR_OFFSET_SLAVE 0x1000 4991ed5349SWolfram Sang 5091ed5349SWolfram Sang #define I2C_ADDR_7BITS_MAX 0x77 5191ed5349SWolfram Sang #define I2C_ADDR_7BITS_COUNT (I2C_ADDR_7BITS_MAX + 1) 5291ed5349SWolfram Sang 53dde67eb1SPeter Rosin #define I2C_ADDR_DEVICE_ID 0x7c 54dde67eb1SPeter Rosin 5561e3d0f7SWolfram Sang /* 5661e3d0f7SWolfram Sang * core_lock protects i2c_adapter_idr, and guarantees that device detection, 570c36dd37SWolfram Sang * deletion of detected devices are serialized 5861e3d0f7SWolfram Sang */ 5991ed5349SWolfram Sang static DEFINE_MUTEX(core_lock); 6091ed5349SWolfram Sang static DEFINE_IDR(i2c_adapter_idr); 6191ed5349SWolfram Sang 6291ed5349SWolfram Sang static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); 6391ed5349SWolfram Sang 6450888b01SDavidlohr Bueso static DEFINE_STATIC_KEY_FALSE(i2c_trace_msg_key); 6591ed5349SWolfram Sang static bool is_registered; 6691ed5349SWolfram Sang 6791ed5349SWolfram Sang int i2c_transfer_trace_reg(void) 6891ed5349SWolfram Sang { 6950888b01SDavidlohr Bueso static_branch_inc(&i2c_trace_msg_key); 7091ed5349SWolfram Sang return 0; 7191ed5349SWolfram Sang } 7291ed5349SWolfram Sang 7391ed5349SWolfram Sang void i2c_transfer_trace_unreg(void) 7491ed5349SWolfram Sang { 7550888b01SDavidlohr Bueso static_branch_dec(&i2c_trace_msg_key); 7691ed5349SWolfram Sang } 7791ed5349SWolfram Sang 7891ed5349SWolfram Sang const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, 7991ed5349SWolfram Sang const struct i2c_client *client) 8091ed5349SWolfram Sang { 8191ed5349SWolfram Sang if (!(id && client)) 8291ed5349SWolfram Sang return NULL; 8391ed5349SWolfram Sang 8491ed5349SWolfram Sang while (id->name[0]) { 8591ed5349SWolfram Sang if (strcmp(client->name, id->name) == 0) 8691ed5349SWolfram Sang return id; 8791ed5349SWolfram Sang id++; 8891ed5349SWolfram Sang } 8991ed5349SWolfram Sang return NULL; 9091ed5349SWolfram Sang } 9191ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_match_id); 9291ed5349SWolfram Sang 9391ed5349SWolfram Sang static int i2c_device_match(struct device *dev, struct device_driver *drv) 9491ed5349SWolfram Sang { 9591ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 9691ed5349SWolfram Sang struct i2c_driver *driver; 9791ed5349SWolfram Sang 9891ed5349SWolfram Sang 9991ed5349SWolfram Sang /* Attempt an OF style match */ 10091ed5349SWolfram Sang if (i2c_of_match_device(drv->of_match_table, client)) 10191ed5349SWolfram Sang return 1; 10291ed5349SWolfram Sang 10391ed5349SWolfram Sang /* Then ACPI style match */ 10491ed5349SWolfram Sang if (acpi_driver_match_device(dev, drv)) 10591ed5349SWolfram Sang return 1; 10691ed5349SWolfram Sang 10791ed5349SWolfram Sang driver = to_i2c_driver(drv); 10891ed5349SWolfram Sang 10991ed5349SWolfram Sang /* Finally an I2C match */ 11091ed5349SWolfram Sang if (i2c_match_id(driver->id_table, client)) 11191ed5349SWolfram Sang return 1; 11291ed5349SWolfram Sang 11391ed5349SWolfram Sang return 0; 11491ed5349SWolfram Sang } 11591ed5349SWolfram Sang 11691ed5349SWolfram Sang static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) 11791ed5349SWolfram Sang { 11891ed5349SWolfram Sang struct i2c_client *client = to_i2c_client(dev); 11991ed5349SWolfram Sang int rc; 12091ed5349SWolfram Sang 121af503716SJavier Martinez Canillas rc = of_device_uevent_modalias(dev, env); 122af503716SJavier Martinez Canillas if (rc != -ENODEV) 123af503716SJavier Martinez Canillas return rc; 124af503716SJavier Martinez Canillas 12591ed5349SWolfram Sang rc = acpi_device_uevent_modalias(dev, env); 12691ed5349SWolfram Sang if (rc != -ENODEV) 12791ed5349SWolfram Sang return rc; 12891ed5349SWolfram Sang 12991ed5349SWolfram Sang return add_uevent_var(env, "MODALIAS=%s%s", I2C_MODULE_PREFIX, client->name); 13091ed5349SWolfram Sang } 13191ed5349SWolfram Sang 13291ed5349SWolfram Sang /* i2c bus recovery routines */ 13391ed5349SWolfram Sang static int get_scl_gpio_value(struct i2c_adapter *adap) 13491ed5349SWolfram Sang { 1353991c5c8SPhil Reid return gpiod_get_value_cansleep(adap->bus_recovery_info->scl_gpiod); 13691ed5349SWolfram Sang } 13791ed5349SWolfram Sang 13891ed5349SWolfram Sang static void set_scl_gpio_value(struct i2c_adapter *adap, int val) 13991ed5349SWolfram Sang { 1403991c5c8SPhil Reid gpiod_set_value_cansleep(adap->bus_recovery_info->scl_gpiod, val); 14191ed5349SWolfram Sang } 14291ed5349SWolfram Sang 14391ed5349SWolfram Sang static int get_sda_gpio_value(struct i2c_adapter *adap) 14491ed5349SWolfram Sang { 1453991c5c8SPhil Reid return gpiod_get_value_cansleep(adap->bus_recovery_info->sda_gpiod); 14691ed5349SWolfram Sang } 14791ed5349SWolfram Sang 1488092178fSWolfram Sang static void set_sda_gpio_value(struct i2c_adapter *adap, int val) 14991ed5349SWolfram Sang { 1508092178fSWolfram Sang gpiod_set_value_cansleep(adap->bus_recovery_info->sda_gpiod, val); 15191ed5349SWolfram Sang } 15291ed5349SWolfram Sang 1537ca5f6beSWolfram Sang static int i2c_generic_bus_free(struct i2c_adapter *adap) 1547ca5f6beSWolfram Sang { 1557ca5f6beSWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 1567ca5f6beSWolfram Sang int ret = -EOPNOTSUPP; 1577ca5f6beSWolfram Sang 1587ca5f6beSWolfram Sang if (bri->get_bus_free) 1597ca5f6beSWolfram Sang ret = bri->get_bus_free(adap); 1607ca5f6beSWolfram Sang else if (bri->get_sda) 1617ca5f6beSWolfram Sang ret = bri->get_sda(adap); 1627ca5f6beSWolfram Sang 1637ca5f6beSWolfram Sang if (ret < 0) 1647ca5f6beSWolfram Sang return ret; 1657ca5f6beSWolfram Sang 1667ca5f6beSWolfram Sang return ret ? 0 : -EBUSY; 1677ca5f6beSWolfram Sang } 1687ca5f6beSWolfram Sang 16991ed5349SWolfram Sang /* 17091ed5349SWolfram Sang * We are generating clock pulses. ndelay() determines durating of clk pulses. 17191ed5349SWolfram Sang * We will generate clock with rate 100 KHz and so duration of both clock levels 17291ed5349SWolfram Sang * is: delay in ns = (10^6 / 100) / 2 17391ed5349SWolfram Sang */ 17491ed5349SWolfram Sang #define RECOVERY_NDELAY 5000 17591ed5349SWolfram Sang #define RECOVERY_CLK_CNT 9 17691ed5349SWolfram Sang 177e1eb7d28SPhil Reid int i2c_generic_scl_recovery(struct i2c_adapter *adap) 17891ed5349SWolfram Sang { 17991ed5349SWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 180cf676908SLinus Torvalds int i = 0, scl = 1, ret = 0; 18191ed5349SWolfram Sang 18291ed5349SWolfram Sang if (bri->prepare_recovery) 18391ed5349SWolfram Sang bri->prepare_recovery(adap); 18491ed5349SWolfram Sang 185c4ae05b9SWolfram Sang /* 186c4ae05b9SWolfram Sang * If we can set SDA, we will always create a STOP to ensure additional 187c4ae05b9SWolfram Sang * pulses will do no harm. This is achieved by letting SDA follow SCL 188c4ae05b9SWolfram Sang * half a cycle later. Check the 'incomplete_write_byte' fault injector 189c4ae05b9SWolfram Sang * for details. 190c4ae05b9SWolfram Sang */ 191f7ff75e2SWolfram Sang bri->set_scl(adap, scl); 192c4ae05b9SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 19372b08fccSWolfram Sang if (bri->set_sda) 194c4ae05b9SWolfram Sang bri->set_sda(adap, scl); 195c4ae05b9SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 19691ed5349SWolfram Sang 19791ed5349SWolfram Sang /* 19891ed5349SWolfram Sang * By this time SCL is high, as we need to give 9 falling-rising edges 19991ed5349SWolfram Sang */ 20091ed5349SWolfram Sang while (i++ < RECOVERY_CLK_CNT * 2) { 201f7ff75e2SWolfram Sang if (scl) { 20291ed5349SWolfram Sang /* SCL shouldn't be low here */ 20391ed5349SWolfram Sang if (!bri->get_scl(adap)) { 20491ed5349SWolfram Sang dev_err(&adap->dev, 20591ed5349SWolfram Sang "SCL is stuck low, exit recovery\n"); 20691ed5349SWolfram Sang ret = -EBUSY; 20791ed5349SWolfram Sang break; 20891ed5349SWolfram Sang } 20991ed5349SWolfram Sang } 21091ed5349SWolfram Sang 211f7ff75e2SWolfram Sang scl = !scl; 212f7ff75e2SWolfram Sang bri->set_scl(adap, scl); 213c4ae05b9SWolfram Sang /* Creating STOP again, see above */ 214abe41184SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 215abe41184SWolfram Sang if (bri->set_sda) 216f7ff75e2SWolfram Sang bri->set_sda(adap, scl); 217abe41184SWolfram Sang ndelay(RECOVERY_NDELAY / 2); 2180b71026cSWolfram Sang 219f7ff75e2SWolfram Sang if (scl) { 2207ca5f6beSWolfram Sang ret = i2c_generic_bus_free(adap); 2210b71026cSWolfram Sang if (ret == 0) 2220b71026cSWolfram Sang break; 22391ed5349SWolfram Sang } 22491ed5349SWolfram Sang } 22591ed5349SWolfram Sang 2267ca5f6beSWolfram Sang /* If we can't check bus status, assume recovery worked */ 2277ca5f6beSWolfram Sang if (ret == -EOPNOTSUPP) 2287ca5f6beSWolfram Sang ret = 0; 2292806e6adSWolfram Sang 23091ed5349SWolfram Sang if (bri->unprepare_recovery) 23191ed5349SWolfram Sang bri->unprepare_recovery(adap); 23291ed5349SWolfram Sang 23391ed5349SWolfram Sang return ret; 23491ed5349SWolfram Sang } 23591ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); 23691ed5349SWolfram Sang 23791ed5349SWolfram Sang int i2c_recover_bus(struct i2c_adapter *adap) 23891ed5349SWolfram Sang { 23991ed5349SWolfram Sang if (!adap->bus_recovery_info) 24091ed5349SWolfram Sang return -EOPNOTSUPP; 24191ed5349SWolfram Sang 24291ed5349SWolfram Sang dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); 24391ed5349SWolfram Sang return adap->bus_recovery_info->recover_bus(adap); 24491ed5349SWolfram Sang } 24591ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_recover_bus); 24691ed5349SWolfram Sang 24791ed5349SWolfram Sang static void i2c_init_recovery(struct i2c_adapter *adap) 24891ed5349SWolfram Sang { 24991ed5349SWolfram Sang struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; 25091ed5349SWolfram Sang char *err_str; 25191ed5349SWolfram Sang 25291ed5349SWolfram Sang if (!bri) 25391ed5349SWolfram Sang return; 25491ed5349SWolfram Sang 25591ed5349SWolfram Sang if (!bri->recover_bus) { 25691ed5349SWolfram Sang err_str = "no recover_bus() found"; 25791ed5349SWolfram Sang goto err; 25891ed5349SWolfram Sang } 25991ed5349SWolfram Sang 2603991c5c8SPhil Reid if (bri->scl_gpiod && bri->recover_bus == i2c_generic_scl_recovery) { 26191ed5349SWolfram Sang bri->get_scl = get_scl_gpio_value; 26291ed5349SWolfram Sang bri->set_scl = set_scl_gpio_value; 2638092178fSWolfram Sang if (bri->sda_gpiod) { 2643991c5c8SPhil Reid bri->get_sda = get_sda_gpio_value; 2658092178fSWolfram Sang /* FIXME: add proper flag instead of '0' once available */ 2668092178fSWolfram Sang if (gpiod_get_direction(bri->sda_gpiod) == 0) 2678092178fSWolfram Sang bri->set_sda = set_sda_gpio_value; 2688092178fSWolfram Sang } 2693991c5c8SPhil Reid return; 2703991c5c8SPhil Reid } 2713991c5c8SPhil Reid 272e1eb7d28SPhil Reid if (bri->recover_bus == i2c_generic_scl_recovery) { 27391ed5349SWolfram Sang /* Generic SCL recovery */ 27491ed5349SWolfram Sang if (!bri->set_scl || !bri->get_scl) { 27591ed5349SWolfram Sang err_str = "no {get|set}_scl() found"; 27691ed5349SWolfram Sang goto err; 27791ed5349SWolfram Sang } 278ffc59c49SWolfram Sang if (!bri->set_sda && !bri->get_sda) { 279ffc59c49SWolfram Sang err_str = "either get_sda() or set_sda() needed"; 280ffc59c49SWolfram Sang goto err; 281ffc59c49SWolfram Sang } 28291ed5349SWolfram Sang } 28391ed5349SWolfram Sang 28491ed5349SWolfram Sang return; 28591ed5349SWolfram Sang err: 28691ed5349SWolfram Sang dev_err(&adap->dev, "Not using recovery: %s\n", err_str); 28791ed5349SWolfram Sang adap->bus_recovery_info = NULL; 28891ed5349SWolfram Sang } 28991ed5349SWolfram Sang 29091ed5349SWolfram Sang static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) 29191ed5349SWolfram Sang { 29291ed5349SWolfram Sang struct i2c_adapter *adap = client->adapter; 29391ed5349SWolfram Sang unsigned int irq; 29491ed5349SWolfram Sang 29591ed5349SWolfram Sang if (!adap->host_notify_domain) 29691ed5349SWolfram Sang return -ENXIO; 29791ed5349SWolfram Sang 29891ed5349SWolfram Sang if (client->flags & I2C_CLIENT_TEN) 29991ed5349SWolfram Sang return -EINVAL; 30091ed5349SWolfram Sang 301b9bb3fdfSCharles Keepax irq = irq_create_mapping(adap->host_notify_domain, client->addr); 30291ed5349SWolfram Sang 30391ed5349SWolfram Sang return irq > 0 ? irq : -ENXIO; 30491ed5349SWolfram Sang } 30591ed5349SWolfram Sang 30691ed5349SWolfram Sang static int i2c_device_probe(struct device *dev) 30791ed5349SWolfram Sang { 30891ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 30991ed5349SWolfram Sang struct i2c_driver *driver; 31091ed5349SWolfram Sang int status; 31191ed5349SWolfram Sang 31291ed5349SWolfram Sang if (!client) 31391ed5349SWolfram Sang return 0; 31491ed5349SWolfram Sang 31591ed5349SWolfram Sang driver = to_i2c_driver(dev->driver); 31691ed5349SWolfram Sang 3176e76cb7dSCharles Keepax client->irq = client->init_irq; 3186e76cb7dSCharles Keepax 31991ed5349SWolfram Sang if (!client->irq && !driver->disable_i2c_core_irq_mapping) { 32091ed5349SWolfram Sang int irq = -ENOENT; 32191ed5349SWolfram Sang 32291ed5349SWolfram Sang if (client->flags & I2C_CLIENT_HOST_NOTIFY) { 32391ed5349SWolfram Sang dev_dbg(dev, "Using Host Notify IRQ\n"); 32472bfcee1SJarkko Nikula /* Keep adapter active when Host Notify is required */ 32572bfcee1SJarkko Nikula pm_runtime_get_sync(&client->adapter->dev); 32691ed5349SWolfram Sang irq = i2c_smbus_host_notify_to_irq(client); 32791ed5349SWolfram Sang } else if (dev->of_node) { 32891ed5349SWolfram Sang irq = of_irq_get_byname(dev->of_node, "irq"); 32991ed5349SWolfram Sang if (irq == -EINVAL || irq == -ENODATA) 33091ed5349SWolfram Sang irq = of_irq_get(dev->of_node, 0); 33191ed5349SWolfram Sang } else if (ACPI_COMPANION(dev)) { 33216c9db1dSCharles Keepax irq = i2c_acpi_get_irq(client); 33391ed5349SWolfram Sang } 33491ed5349SWolfram Sang if (irq == -EPROBE_DEFER) 33591ed5349SWolfram Sang return irq; 33691ed5349SWolfram Sang 33791ed5349SWolfram Sang if (irq < 0) 33891ed5349SWolfram Sang irq = 0; 33991ed5349SWolfram Sang 34091ed5349SWolfram Sang client->irq = irq; 34191ed5349SWolfram Sang } 34291ed5349SWolfram Sang 34391ed5349SWolfram Sang /* 344f4b17a14SJavier Martinez Canillas * An I2C ID table is not mandatory, if and only if, a suitable OF 345f4b17a14SJavier Martinez Canillas * or ACPI ID table is supplied for the probing device. 34691ed5349SWolfram Sang */ 34791ed5349SWolfram Sang if (!driver->id_table && 348c64ffff7SAndy Shevchenko !i2c_acpi_match_device(dev->driver->acpi_match_table, client) && 34991ed5349SWolfram Sang !i2c_of_match_device(dev->driver->of_match_table, client)) 35091ed5349SWolfram Sang return -ENODEV; 35191ed5349SWolfram Sang 35291ed5349SWolfram Sang if (client->flags & I2C_CLIENT_WAKE) { 35391ed5349SWolfram Sang int wakeirq = -ENOENT; 35491ed5349SWolfram Sang 35591ed5349SWolfram Sang if (dev->of_node) { 35691ed5349SWolfram Sang wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); 35791ed5349SWolfram Sang if (wakeirq == -EPROBE_DEFER) 35891ed5349SWolfram Sang return wakeirq; 35991ed5349SWolfram Sang } 36091ed5349SWolfram Sang 36191ed5349SWolfram Sang device_init_wakeup(&client->dev, true); 36291ed5349SWolfram Sang 36391ed5349SWolfram Sang if (wakeirq > 0 && wakeirq != client->irq) 36491ed5349SWolfram Sang status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); 36591ed5349SWolfram Sang else if (client->irq > 0) 36691ed5349SWolfram Sang status = dev_pm_set_wake_irq(dev, client->irq); 36791ed5349SWolfram Sang else 36891ed5349SWolfram Sang status = 0; 36991ed5349SWolfram Sang 37091ed5349SWolfram Sang if (status) 37191ed5349SWolfram Sang dev_warn(&client->dev, "failed to set up wakeup irq\n"); 37291ed5349SWolfram Sang } 37391ed5349SWolfram Sang 37491ed5349SWolfram Sang dev_dbg(dev, "probe\n"); 37591ed5349SWolfram Sang 37691ed5349SWolfram Sang status = of_clk_set_defaults(dev->of_node, false); 37791ed5349SWolfram Sang if (status < 0) 37891ed5349SWolfram Sang goto err_clear_wakeup_irq; 37991ed5349SWolfram Sang 38091ed5349SWolfram Sang status = dev_pm_domain_attach(&client->dev, true); 381e6a20b6cSUlf Hansson if (status) 38291ed5349SWolfram Sang goto err_clear_wakeup_irq; 38391ed5349SWolfram Sang 38491ed5349SWolfram Sang /* 38591ed5349SWolfram Sang * When there are no more users of probe(), 38691ed5349SWolfram Sang * rename probe_new to probe. 38791ed5349SWolfram Sang */ 38891ed5349SWolfram Sang if (driver->probe_new) 38991ed5349SWolfram Sang status = driver->probe_new(client); 39091ed5349SWolfram Sang else if (driver->probe) 39191ed5349SWolfram Sang status = driver->probe(client, 39291ed5349SWolfram Sang i2c_match_id(driver->id_table, client)); 39391ed5349SWolfram Sang else 39491ed5349SWolfram Sang status = -EINVAL; 39591ed5349SWolfram Sang 39691ed5349SWolfram Sang if (status) 39791ed5349SWolfram Sang goto err_detach_pm_domain; 39891ed5349SWolfram Sang 39991ed5349SWolfram Sang return 0; 40091ed5349SWolfram Sang 40191ed5349SWolfram Sang err_detach_pm_domain: 40291ed5349SWolfram Sang dev_pm_domain_detach(&client->dev, true); 40391ed5349SWolfram Sang err_clear_wakeup_irq: 40491ed5349SWolfram Sang dev_pm_clear_wake_irq(&client->dev); 40591ed5349SWolfram Sang device_init_wakeup(&client->dev, false); 40691ed5349SWolfram Sang return status; 40791ed5349SWolfram Sang } 40891ed5349SWolfram Sang 40991ed5349SWolfram Sang static int i2c_device_remove(struct device *dev) 41091ed5349SWolfram Sang { 41191ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 41291ed5349SWolfram Sang struct i2c_driver *driver; 41391ed5349SWolfram Sang int status = 0; 41491ed5349SWolfram Sang 41591ed5349SWolfram Sang if (!client || !dev->driver) 41691ed5349SWolfram Sang return 0; 41791ed5349SWolfram Sang 41891ed5349SWolfram Sang driver = to_i2c_driver(dev->driver); 41991ed5349SWolfram Sang if (driver->remove) { 42091ed5349SWolfram Sang dev_dbg(dev, "remove\n"); 42191ed5349SWolfram Sang status = driver->remove(client); 42291ed5349SWolfram Sang } 42391ed5349SWolfram Sang 42491ed5349SWolfram Sang dev_pm_domain_detach(&client->dev, true); 42591ed5349SWolfram Sang 42691ed5349SWolfram Sang dev_pm_clear_wake_irq(&client->dev); 42791ed5349SWolfram Sang device_init_wakeup(&client->dev, false); 42891ed5349SWolfram Sang 4296e76cb7dSCharles Keepax client->irq = 0; 43072bfcee1SJarkko Nikula if (client->flags & I2C_CLIENT_HOST_NOTIFY) 43172bfcee1SJarkko Nikula pm_runtime_put(&client->adapter->dev); 4326f108dd7SCharles Keepax 43391ed5349SWolfram Sang return status; 43491ed5349SWolfram Sang } 43591ed5349SWolfram Sang 43691ed5349SWolfram Sang static void i2c_device_shutdown(struct device *dev) 43791ed5349SWolfram Sang { 43891ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 43991ed5349SWolfram Sang struct i2c_driver *driver; 44091ed5349SWolfram Sang 44191ed5349SWolfram Sang if (!client || !dev->driver) 44291ed5349SWolfram Sang return; 44391ed5349SWolfram Sang driver = to_i2c_driver(dev->driver); 44491ed5349SWolfram Sang if (driver->shutdown) 44591ed5349SWolfram Sang driver->shutdown(client); 44691ed5349SWolfram Sang } 44791ed5349SWolfram Sang 44891ed5349SWolfram Sang static void i2c_client_dev_release(struct device *dev) 44991ed5349SWolfram Sang { 45091ed5349SWolfram Sang kfree(to_i2c_client(dev)); 45191ed5349SWolfram Sang } 45291ed5349SWolfram Sang 45391ed5349SWolfram Sang static ssize_t 45491ed5349SWolfram Sang show_name(struct device *dev, struct device_attribute *attr, char *buf) 45591ed5349SWolfram Sang { 45691ed5349SWolfram Sang return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? 45791ed5349SWolfram Sang to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); 45891ed5349SWolfram Sang } 45991ed5349SWolfram Sang static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); 46091ed5349SWolfram Sang 46191ed5349SWolfram Sang static ssize_t 46291ed5349SWolfram Sang show_modalias(struct device *dev, struct device_attribute *attr, char *buf) 46391ed5349SWolfram Sang { 46491ed5349SWolfram Sang struct i2c_client *client = to_i2c_client(dev); 46591ed5349SWolfram Sang int len; 46691ed5349SWolfram Sang 467af503716SJavier Martinez Canillas len = of_device_modalias(dev, buf, PAGE_SIZE); 468af503716SJavier Martinez Canillas if (len != -ENODEV) 469af503716SJavier Martinez Canillas return len; 470af503716SJavier Martinez Canillas 47191ed5349SWolfram Sang len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); 47291ed5349SWolfram Sang if (len != -ENODEV) 47391ed5349SWolfram Sang return len; 47491ed5349SWolfram Sang 47591ed5349SWolfram Sang return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); 47691ed5349SWolfram Sang } 47791ed5349SWolfram Sang static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); 47891ed5349SWolfram Sang 47991ed5349SWolfram Sang static struct attribute *i2c_dev_attrs[] = { 48091ed5349SWolfram Sang &dev_attr_name.attr, 48191ed5349SWolfram Sang /* modalias helps coldplug: modprobe $(cat .../modalias) */ 48291ed5349SWolfram Sang &dev_attr_modalias.attr, 48391ed5349SWolfram Sang NULL 48491ed5349SWolfram Sang }; 48591ed5349SWolfram Sang ATTRIBUTE_GROUPS(i2c_dev); 48691ed5349SWolfram Sang 48791ed5349SWolfram Sang struct bus_type i2c_bus_type = { 48891ed5349SWolfram Sang .name = "i2c", 48991ed5349SWolfram Sang .match = i2c_device_match, 49091ed5349SWolfram Sang .probe = i2c_device_probe, 49191ed5349SWolfram Sang .remove = i2c_device_remove, 49291ed5349SWolfram Sang .shutdown = i2c_device_shutdown, 49391ed5349SWolfram Sang }; 49491ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_bus_type); 49591ed5349SWolfram Sang 49691ed5349SWolfram Sang struct device_type i2c_client_type = { 49791ed5349SWolfram Sang .groups = i2c_dev_groups, 49891ed5349SWolfram Sang .uevent = i2c_device_uevent, 49991ed5349SWolfram Sang .release = i2c_client_dev_release, 50091ed5349SWolfram Sang }; 50191ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_client_type); 50291ed5349SWolfram Sang 50391ed5349SWolfram Sang 50491ed5349SWolfram Sang /** 50591ed5349SWolfram Sang * i2c_verify_client - return parameter as i2c_client, or NULL 50691ed5349SWolfram Sang * @dev: device, probably from some driver model iterator 50791ed5349SWolfram Sang * 50891ed5349SWolfram Sang * When traversing the driver model tree, perhaps using driver model 50991ed5349SWolfram Sang * iterators like @device_for_each_child(), you can't assume very much 51091ed5349SWolfram Sang * about the nodes you find. Use this function to avoid oopses caused 51191ed5349SWolfram Sang * by wrongly treating some non-I2C device as an i2c_client. 51291ed5349SWolfram Sang */ 51391ed5349SWolfram Sang struct i2c_client *i2c_verify_client(struct device *dev) 51491ed5349SWolfram Sang { 51591ed5349SWolfram Sang return (dev->type == &i2c_client_type) 51691ed5349SWolfram Sang ? to_i2c_client(dev) 51791ed5349SWolfram Sang : NULL; 51891ed5349SWolfram Sang } 51991ed5349SWolfram Sang EXPORT_SYMBOL(i2c_verify_client); 52091ed5349SWolfram Sang 52191ed5349SWolfram Sang 52291ed5349SWolfram Sang /* Return a unique address which takes the flags of the client into account */ 52391ed5349SWolfram Sang static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) 52491ed5349SWolfram Sang { 52591ed5349SWolfram Sang unsigned short addr = client->addr; 52691ed5349SWolfram Sang 52791ed5349SWolfram Sang /* For some client flags, add an arbitrary offset to avoid collisions */ 52891ed5349SWolfram Sang if (client->flags & I2C_CLIENT_TEN) 52991ed5349SWolfram Sang addr |= I2C_ADDR_OFFSET_TEN_BIT; 53091ed5349SWolfram Sang 53191ed5349SWolfram Sang if (client->flags & I2C_CLIENT_SLAVE) 53291ed5349SWolfram Sang addr |= I2C_ADDR_OFFSET_SLAVE; 53391ed5349SWolfram Sang 53491ed5349SWolfram Sang return addr; 53591ed5349SWolfram Sang } 53691ed5349SWolfram Sang 53791ed5349SWolfram Sang /* This is a permissive address validity check, I2C address map constraints 53891ed5349SWolfram Sang * are purposely not enforced, except for the general call address. */ 539398432edSWolfram Sang static int i2c_check_addr_validity(unsigned int addr, unsigned short flags) 54091ed5349SWolfram Sang { 54191ed5349SWolfram Sang if (flags & I2C_CLIENT_TEN) { 54291ed5349SWolfram Sang /* 10-bit address, all values are valid */ 54391ed5349SWolfram Sang if (addr > 0x3ff) 54491ed5349SWolfram Sang return -EINVAL; 54591ed5349SWolfram Sang } else { 54691ed5349SWolfram Sang /* 7-bit address, reject the general call address */ 54791ed5349SWolfram Sang if (addr == 0x00 || addr > 0x7f) 54891ed5349SWolfram Sang return -EINVAL; 54991ed5349SWolfram Sang } 55091ed5349SWolfram Sang return 0; 55191ed5349SWolfram Sang } 55291ed5349SWolfram Sang 55391ed5349SWolfram Sang /* And this is a strict address validity check, used when probing. If a 55491ed5349SWolfram Sang * device uses a reserved address, then it shouldn't be probed. 7-bit 55591ed5349SWolfram Sang * addressing is assumed, 10-bit address devices are rare and should be 55691ed5349SWolfram Sang * explicitly enumerated. */ 557e4991ecdSWolfram Sang int i2c_check_7bit_addr_validity_strict(unsigned short addr) 55891ed5349SWolfram Sang { 55991ed5349SWolfram Sang /* 56091ed5349SWolfram Sang * Reserved addresses per I2C specification: 56191ed5349SWolfram Sang * 0x00 General call address / START byte 56291ed5349SWolfram Sang * 0x01 CBUS address 56391ed5349SWolfram Sang * 0x02 Reserved for different bus format 56491ed5349SWolfram Sang * 0x03 Reserved for future purposes 56591ed5349SWolfram Sang * 0x04-0x07 Hs-mode master code 56691ed5349SWolfram Sang * 0x78-0x7b 10-bit slave addressing 56791ed5349SWolfram Sang * 0x7c-0x7f Reserved for future purposes 56891ed5349SWolfram Sang */ 56991ed5349SWolfram Sang if (addr < 0x08 || addr > 0x77) 57091ed5349SWolfram Sang return -EINVAL; 57191ed5349SWolfram Sang return 0; 57291ed5349SWolfram Sang } 57391ed5349SWolfram Sang 57491ed5349SWolfram Sang static int __i2c_check_addr_busy(struct device *dev, void *addrp) 57591ed5349SWolfram Sang { 57691ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 57791ed5349SWolfram Sang int addr = *(int *)addrp; 57891ed5349SWolfram Sang 57991ed5349SWolfram Sang if (client && i2c_encode_flags_to_addr(client) == addr) 58091ed5349SWolfram Sang return -EBUSY; 58191ed5349SWolfram Sang return 0; 58291ed5349SWolfram Sang } 58391ed5349SWolfram Sang 58491ed5349SWolfram Sang /* walk up mux tree */ 58591ed5349SWolfram Sang static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) 58691ed5349SWolfram Sang { 58791ed5349SWolfram Sang struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); 58891ed5349SWolfram Sang int result; 58991ed5349SWolfram Sang 59091ed5349SWolfram Sang result = device_for_each_child(&adapter->dev, &addr, 59191ed5349SWolfram Sang __i2c_check_addr_busy); 59291ed5349SWolfram Sang 59391ed5349SWolfram Sang if (!result && parent) 59491ed5349SWolfram Sang result = i2c_check_mux_parents(parent, addr); 59591ed5349SWolfram Sang 59691ed5349SWolfram Sang return result; 59791ed5349SWolfram Sang } 59891ed5349SWolfram Sang 59991ed5349SWolfram Sang /* recurse down mux tree */ 60091ed5349SWolfram Sang static int i2c_check_mux_children(struct device *dev, void *addrp) 60191ed5349SWolfram Sang { 60291ed5349SWolfram Sang int result; 60391ed5349SWolfram Sang 60491ed5349SWolfram Sang if (dev->type == &i2c_adapter_type) 60591ed5349SWolfram Sang result = device_for_each_child(dev, addrp, 60691ed5349SWolfram Sang i2c_check_mux_children); 60791ed5349SWolfram Sang else 60891ed5349SWolfram Sang result = __i2c_check_addr_busy(dev, addrp); 60991ed5349SWolfram Sang 61091ed5349SWolfram Sang return result; 61191ed5349SWolfram Sang } 61291ed5349SWolfram Sang 61391ed5349SWolfram Sang static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) 61491ed5349SWolfram Sang { 61591ed5349SWolfram Sang struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); 61691ed5349SWolfram Sang int result = 0; 61791ed5349SWolfram Sang 61891ed5349SWolfram Sang if (parent) 61991ed5349SWolfram Sang result = i2c_check_mux_parents(parent, addr); 62091ed5349SWolfram Sang 62191ed5349SWolfram Sang if (!result) 62291ed5349SWolfram Sang result = device_for_each_child(&adapter->dev, &addr, 62391ed5349SWolfram Sang i2c_check_mux_children); 62491ed5349SWolfram Sang 62591ed5349SWolfram Sang return result; 62691ed5349SWolfram Sang } 62791ed5349SWolfram Sang 62891ed5349SWolfram Sang /** 62991ed5349SWolfram Sang * i2c_adapter_lock_bus - Get exclusive access to an I2C bus segment 63091ed5349SWolfram Sang * @adapter: Target I2C bus segment 63191ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT 63291ed5349SWolfram Sang * locks only this branch in the adapter tree 63391ed5349SWolfram Sang */ 63491ed5349SWolfram Sang static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, 63591ed5349SWolfram Sang unsigned int flags) 63691ed5349SWolfram Sang { 6377b94ea50SPeter Rosin rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter)); 63891ed5349SWolfram Sang } 63991ed5349SWolfram Sang 64091ed5349SWolfram Sang /** 64191ed5349SWolfram Sang * i2c_adapter_trylock_bus - Try to get exclusive access to an I2C bus segment 64291ed5349SWolfram Sang * @adapter: Target I2C bus segment 64391ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER trylocks the root i2c adapter, I2C_LOCK_SEGMENT 64491ed5349SWolfram Sang * trylocks only this branch in the adapter tree 64591ed5349SWolfram Sang */ 64691ed5349SWolfram Sang static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, 64791ed5349SWolfram Sang unsigned int flags) 64891ed5349SWolfram Sang { 64991ed5349SWolfram Sang return rt_mutex_trylock(&adapter->bus_lock); 65091ed5349SWolfram Sang } 65191ed5349SWolfram Sang 65291ed5349SWolfram Sang /** 65391ed5349SWolfram Sang * i2c_adapter_unlock_bus - Release exclusive access to an I2C bus segment 65491ed5349SWolfram Sang * @adapter: Target I2C bus segment 65591ed5349SWolfram Sang * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT 65691ed5349SWolfram Sang * unlocks only this branch in the adapter tree 65791ed5349SWolfram Sang */ 65891ed5349SWolfram Sang static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, 65991ed5349SWolfram Sang unsigned int flags) 66091ed5349SWolfram Sang { 66191ed5349SWolfram Sang rt_mutex_unlock(&adapter->bus_lock); 66291ed5349SWolfram Sang } 66391ed5349SWolfram Sang 66491ed5349SWolfram Sang static void i2c_dev_set_name(struct i2c_adapter *adap, 665728fe6ceSHans de Goede struct i2c_client *client, 666728fe6ceSHans de Goede struct i2c_board_info const *info) 66791ed5349SWolfram Sang { 66891ed5349SWolfram Sang struct acpi_device *adev = ACPI_COMPANION(&client->dev); 66991ed5349SWolfram Sang 670728fe6ceSHans de Goede if (info && info->dev_name) { 671728fe6ceSHans de Goede dev_set_name(&client->dev, "i2c-%s", info->dev_name); 672728fe6ceSHans de Goede return; 673728fe6ceSHans de Goede } 674728fe6ceSHans de Goede 67591ed5349SWolfram Sang if (adev) { 67691ed5349SWolfram Sang dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); 67791ed5349SWolfram Sang return; 67891ed5349SWolfram Sang } 67991ed5349SWolfram Sang 68091ed5349SWolfram Sang dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), 68191ed5349SWolfram Sang i2c_encode_flags_to_addr(client)); 68291ed5349SWolfram Sang } 68391ed5349SWolfram Sang 6841d7534b6SCharles Keepax int i2c_dev_irq_from_resources(const struct resource *resources, 68591ed5349SWolfram Sang unsigned int num_resources) 68691ed5349SWolfram Sang { 68791ed5349SWolfram Sang struct irq_data *irqd; 68891ed5349SWolfram Sang int i; 68991ed5349SWolfram Sang 69091ed5349SWolfram Sang for (i = 0; i < num_resources; i++) { 69191ed5349SWolfram Sang const struct resource *r = &resources[i]; 69291ed5349SWolfram Sang 69391ed5349SWolfram Sang if (resource_type(r) != IORESOURCE_IRQ) 69491ed5349SWolfram Sang continue; 69591ed5349SWolfram Sang 69691ed5349SWolfram Sang if (r->flags & IORESOURCE_BITS) { 69791ed5349SWolfram Sang irqd = irq_get_irq_data(r->start); 69891ed5349SWolfram Sang if (!irqd) 69991ed5349SWolfram Sang break; 70091ed5349SWolfram Sang 70191ed5349SWolfram Sang irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS); 70291ed5349SWolfram Sang } 70391ed5349SWolfram Sang 70491ed5349SWolfram Sang return r->start; 70591ed5349SWolfram Sang } 70691ed5349SWolfram Sang 70791ed5349SWolfram Sang return 0; 70891ed5349SWolfram Sang } 70991ed5349SWolfram Sang 71091ed5349SWolfram Sang /** 7117159dbdaSHeiner Kallweit * i2c_new_client_device - instantiate an i2c device 71291ed5349SWolfram Sang * @adap: the adapter managing the device 71391ed5349SWolfram Sang * @info: describes one I2C device; bus_num is ignored 71491ed5349SWolfram Sang * Context: can sleep 71591ed5349SWolfram Sang * 71691ed5349SWolfram Sang * Create an i2c device. Binding is handled through driver model 71791ed5349SWolfram Sang * probe()/remove() methods. A driver may be bound to this device when we 71891ed5349SWolfram Sang * return from this function, or any later moment (e.g. maybe hotplugging will 71991ed5349SWolfram Sang * load the driver module). This call is not appropriate for use by mainboard 72091ed5349SWolfram Sang * initialization logic, which usually runs during an arch_initcall() long 72191ed5349SWolfram Sang * before any i2c_adapter could exist. 72291ed5349SWolfram Sang * 72391ed5349SWolfram Sang * This returns the new i2c client, which may be saved for later use with 7247159dbdaSHeiner Kallweit * i2c_unregister_device(); or an ERR_PTR to describe the error. 72591ed5349SWolfram Sang */ 726550113d4SWolfram Sang struct i2c_client * 7277159dbdaSHeiner Kallweit i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) 72891ed5349SWolfram Sang { 72991ed5349SWolfram Sang struct i2c_client *client; 73091ed5349SWolfram Sang int status; 73191ed5349SWolfram Sang 73291ed5349SWolfram Sang client = kzalloc(sizeof *client, GFP_KERNEL); 73391ed5349SWolfram Sang if (!client) 7347159dbdaSHeiner Kallweit return ERR_PTR(-ENOMEM); 73591ed5349SWolfram Sang 73691ed5349SWolfram Sang client->adapter = adap; 73791ed5349SWolfram Sang 73891ed5349SWolfram Sang client->dev.platform_data = info->platform_data; 73991ed5349SWolfram Sang client->flags = info->flags; 74091ed5349SWolfram Sang client->addr = info->addr; 74191ed5349SWolfram Sang 74293b6604cSJim Broadus client->init_irq = info->irq; 74393b6604cSJim Broadus if (!client->init_irq) 74493b6604cSJim Broadus client->init_irq = i2c_dev_irq_from_resources(info->resources, 74591ed5349SWolfram Sang info->num_resources); 74691ed5349SWolfram Sang 74791ed5349SWolfram Sang strlcpy(client->name, info->type, sizeof(client->name)); 74891ed5349SWolfram Sang 74991ed5349SWolfram Sang status = i2c_check_addr_validity(client->addr, client->flags); 75091ed5349SWolfram Sang if (status) { 75191ed5349SWolfram Sang dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", 75291ed5349SWolfram Sang client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); 75391ed5349SWolfram Sang goto out_err_silent; 75491ed5349SWolfram Sang } 75591ed5349SWolfram Sang 75691ed5349SWolfram Sang /* Check for address business */ 75791ed5349SWolfram Sang status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); 75891ed5349SWolfram Sang if (status) 75991ed5349SWolfram Sang goto out_err; 76091ed5349SWolfram Sang 76191ed5349SWolfram Sang client->dev.parent = &client->adapter->dev; 76291ed5349SWolfram Sang client->dev.bus = &i2c_bus_type; 76391ed5349SWolfram Sang client->dev.type = &i2c_client_type; 76404782265SBoris Brezillon client->dev.of_node = of_node_get(info->of_node); 76591ed5349SWolfram Sang client->dev.fwnode = info->fwnode; 76691ed5349SWolfram Sang 767728fe6ceSHans de Goede i2c_dev_set_name(adap, client, info); 76891ed5349SWolfram Sang 76991ed5349SWolfram Sang if (info->properties) { 77091ed5349SWolfram Sang status = device_add_properties(&client->dev, info->properties); 77191ed5349SWolfram Sang if (status) { 77291ed5349SWolfram Sang dev_err(&adap->dev, 77391ed5349SWolfram Sang "Failed to add properties to client %s: %d\n", 77491ed5349SWolfram Sang client->name, status); 77504782265SBoris Brezillon goto out_err_put_of_node; 77691ed5349SWolfram Sang } 77791ed5349SWolfram Sang } 77891ed5349SWolfram Sang 77991ed5349SWolfram Sang status = device_register(&client->dev); 78091ed5349SWolfram Sang if (status) 78191ed5349SWolfram Sang goto out_free_props; 78291ed5349SWolfram Sang 78391ed5349SWolfram Sang dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", 78491ed5349SWolfram Sang client->name, dev_name(&client->dev)); 78591ed5349SWolfram Sang 78691ed5349SWolfram Sang return client; 78791ed5349SWolfram Sang 78891ed5349SWolfram Sang out_free_props: 78991ed5349SWolfram Sang if (info->properties) 79091ed5349SWolfram Sang device_remove_properties(&client->dev); 79104782265SBoris Brezillon out_err_put_of_node: 79204782265SBoris Brezillon of_node_put(info->of_node); 79391ed5349SWolfram Sang out_err: 79491ed5349SWolfram Sang dev_err(&adap->dev, 79591ed5349SWolfram Sang "Failed to register i2c client %s at 0x%02x (%d)\n", 79691ed5349SWolfram Sang client->name, client->addr, status); 79791ed5349SWolfram Sang out_err_silent: 79891ed5349SWolfram Sang kfree(client); 7997159dbdaSHeiner Kallweit return ERR_PTR(status); 8007159dbdaSHeiner Kallweit } 8017159dbdaSHeiner Kallweit EXPORT_SYMBOL_GPL(i2c_new_client_device); 8027159dbdaSHeiner Kallweit 8037159dbdaSHeiner Kallweit /** 8047159dbdaSHeiner Kallweit * i2c_new_device - instantiate an i2c device 8057159dbdaSHeiner Kallweit * @adap: the adapter managing the device 8067159dbdaSHeiner Kallweit * @info: describes one I2C device; bus_num is ignored 8077159dbdaSHeiner Kallweit * Context: can sleep 8087159dbdaSHeiner Kallweit * 8097159dbdaSHeiner Kallweit * This deprecated function has the same functionality as 8107159dbdaSHeiner Kallweit * @i2c_new_client_device, it just returns NULL instead of an ERR_PTR in case of 8117159dbdaSHeiner Kallweit * an error for compatibility with current I2C API. It will be removed once all 8127159dbdaSHeiner Kallweit * users are converted. 8137159dbdaSHeiner Kallweit * 8147159dbdaSHeiner Kallweit * This returns the new i2c client, which may be saved for later use with 8157159dbdaSHeiner Kallweit * i2c_unregister_device(); or NULL to indicate an error. 8167159dbdaSHeiner Kallweit */ 8177159dbdaSHeiner Kallweit struct i2c_client * 8187159dbdaSHeiner Kallweit i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) 8197159dbdaSHeiner Kallweit { 8207159dbdaSHeiner Kallweit struct i2c_client *ret; 8217159dbdaSHeiner Kallweit 8227159dbdaSHeiner Kallweit ret = i2c_new_client_device(adap, info); 8237159dbdaSHeiner Kallweit return IS_ERR(ret) ? NULL : ret; 82491ed5349SWolfram Sang } 82591ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_device); 82691ed5349SWolfram Sang 82791ed5349SWolfram Sang 82891ed5349SWolfram Sang /** 82991ed5349SWolfram Sang * i2c_unregister_device - reverse effect of i2c_new_device() 83091ed5349SWolfram Sang * @client: value returned from i2c_new_device() 83191ed5349SWolfram Sang * Context: can sleep 83291ed5349SWolfram Sang */ 83391ed5349SWolfram Sang void i2c_unregister_device(struct i2c_client *client) 83491ed5349SWolfram Sang { 8357b43dd19SAndy Shevchenko if (!client) 8367b43dd19SAndy Shevchenko return; 837e0638fa4SLixin Wang 838e0638fa4SLixin Wang if (client->dev.of_node) { 83991ed5349SWolfram Sang of_node_clear_flag(client->dev.of_node, OF_POPULATED); 840e0638fa4SLixin Wang of_node_put(client->dev.of_node); 841e0638fa4SLixin Wang } 842e0638fa4SLixin Wang 84391ed5349SWolfram Sang if (ACPI_COMPANION(&client->dev)) 84491ed5349SWolfram Sang acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev)); 84591ed5349SWolfram Sang device_unregister(&client->dev); 84691ed5349SWolfram Sang } 84791ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_unregister_device); 84891ed5349SWolfram Sang 84991ed5349SWolfram Sang 85091ed5349SWolfram Sang static const struct i2c_device_id dummy_id[] = { 85191ed5349SWolfram Sang { "dummy", 0 }, 85291ed5349SWolfram Sang { }, 85391ed5349SWolfram Sang }; 85491ed5349SWolfram Sang 85591ed5349SWolfram Sang static int dummy_probe(struct i2c_client *client, 85691ed5349SWolfram Sang const struct i2c_device_id *id) 85791ed5349SWolfram Sang { 85891ed5349SWolfram Sang return 0; 85991ed5349SWolfram Sang } 86091ed5349SWolfram Sang 86191ed5349SWolfram Sang static int dummy_remove(struct i2c_client *client) 86291ed5349SWolfram Sang { 86391ed5349SWolfram Sang return 0; 86491ed5349SWolfram Sang } 86591ed5349SWolfram Sang 86691ed5349SWolfram Sang static struct i2c_driver dummy_driver = { 86791ed5349SWolfram Sang .driver.name = "dummy", 86891ed5349SWolfram Sang .probe = dummy_probe, 86991ed5349SWolfram Sang .remove = dummy_remove, 87091ed5349SWolfram Sang .id_table = dummy_id, 87191ed5349SWolfram Sang }; 87291ed5349SWolfram Sang 87391ed5349SWolfram Sang /** 8747159dbdaSHeiner Kallweit * i2c_new_dummy_device - return a new i2c device bound to a dummy driver 87591ed5349SWolfram Sang * @adapter: the adapter managing the device 87691ed5349SWolfram Sang * @address: seven bit address to be used 87791ed5349SWolfram Sang * Context: can sleep 87891ed5349SWolfram Sang * 87991ed5349SWolfram Sang * This returns an I2C client bound to the "dummy" driver, intended for use 88091ed5349SWolfram Sang * with devices that consume multiple addresses. Examples of such chips 88191ed5349SWolfram Sang * include various EEPROMS (like 24c04 and 24c08 models). 88291ed5349SWolfram Sang * 88391ed5349SWolfram Sang * These dummy devices have two main uses. First, most I2C and SMBus calls 88491ed5349SWolfram Sang * except i2c_transfer() need a client handle; the dummy will be that handle. 88591ed5349SWolfram Sang * And second, this prevents the specified address from being bound to a 88691ed5349SWolfram Sang * different driver. 88791ed5349SWolfram Sang * 88891ed5349SWolfram Sang * This returns the new i2c client, which should be saved for later use with 8897159dbdaSHeiner Kallweit * i2c_unregister_device(); or an ERR_PTR to describe the error. 89091ed5349SWolfram Sang */ 891550113d4SWolfram Sang struct i2c_client *i2c_new_dummy_device(struct i2c_adapter *adapter, u16 address) 89291ed5349SWolfram Sang { 89391ed5349SWolfram Sang struct i2c_board_info info = { 89491ed5349SWolfram Sang I2C_BOARD_INFO("dummy", address), 89591ed5349SWolfram Sang }; 89691ed5349SWolfram Sang 8977159dbdaSHeiner Kallweit return i2c_new_client_device(adapter, &info); 8987159dbdaSHeiner Kallweit } 8997159dbdaSHeiner Kallweit EXPORT_SYMBOL_GPL(i2c_new_dummy_device); 9007159dbdaSHeiner Kallweit 9017159dbdaSHeiner Kallweit /** 9027159dbdaSHeiner Kallweit * i2c_new_dummy - return a new i2c device bound to a dummy driver 9037159dbdaSHeiner Kallweit * @adapter: the adapter managing the device 9047159dbdaSHeiner Kallweit * @address: seven bit address to be used 9057159dbdaSHeiner Kallweit * Context: can sleep 9067159dbdaSHeiner Kallweit * 9077159dbdaSHeiner Kallweit * This deprecated function has the same functionality as @i2c_new_dummy_device, 9087159dbdaSHeiner Kallweit * it just returns NULL instead of an ERR_PTR in case of an error for 9097159dbdaSHeiner Kallweit * compatibility with current I2C API. It will be removed once all users are 9107159dbdaSHeiner Kallweit * converted. 9117159dbdaSHeiner Kallweit * 9127159dbdaSHeiner Kallweit * This returns the new i2c client, which should be saved for later use with 9137159dbdaSHeiner Kallweit * i2c_unregister_device(); or NULL to indicate an error. 9147159dbdaSHeiner Kallweit */ 9157159dbdaSHeiner Kallweit struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) 9167159dbdaSHeiner Kallweit { 9177159dbdaSHeiner Kallweit struct i2c_client *ret; 9187159dbdaSHeiner Kallweit 9197159dbdaSHeiner Kallweit ret = i2c_new_dummy_device(adapter, address); 9207159dbdaSHeiner Kallweit return IS_ERR(ret) ? NULL : ret; 92191ed5349SWolfram Sang } 92291ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_dummy); 92391ed5349SWolfram Sang 924b8f5fe3bSHeiner Kallweit struct i2c_dummy_devres { 925b8f5fe3bSHeiner Kallweit struct i2c_client *client; 926b8f5fe3bSHeiner Kallweit }; 927b8f5fe3bSHeiner Kallweit 928b8f5fe3bSHeiner Kallweit static void devm_i2c_release_dummy(struct device *dev, void *res) 929b8f5fe3bSHeiner Kallweit { 930b8f5fe3bSHeiner Kallweit struct i2c_dummy_devres *this = res; 931b8f5fe3bSHeiner Kallweit 932b8f5fe3bSHeiner Kallweit i2c_unregister_device(this->client); 933b8f5fe3bSHeiner Kallweit } 934b8f5fe3bSHeiner Kallweit 935b8f5fe3bSHeiner Kallweit /** 936b8f5fe3bSHeiner Kallweit * devm_i2c_new_dummy_device - return a new i2c device bound to a dummy driver 937b8f5fe3bSHeiner Kallweit * @dev: device the managed resource is bound to 938b8f5fe3bSHeiner Kallweit * @adapter: the adapter managing the device 939b8f5fe3bSHeiner Kallweit * @address: seven bit address to be used 940b8f5fe3bSHeiner Kallweit * Context: can sleep 941b8f5fe3bSHeiner Kallweit * 942b8f5fe3bSHeiner Kallweit * This is the device-managed version of @i2c_new_dummy_device. It returns the 943b8f5fe3bSHeiner Kallweit * new i2c client or an ERR_PTR in case of an error. 944b8f5fe3bSHeiner Kallweit */ 945b8f5fe3bSHeiner Kallweit struct i2c_client *devm_i2c_new_dummy_device(struct device *dev, 946b8f5fe3bSHeiner Kallweit struct i2c_adapter *adapter, 947b8f5fe3bSHeiner Kallweit u16 address) 948b8f5fe3bSHeiner Kallweit { 949b8f5fe3bSHeiner Kallweit struct i2c_dummy_devres *dr; 950b8f5fe3bSHeiner Kallweit struct i2c_client *client; 951b8f5fe3bSHeiner Kallweit 952b8f5fe3bSHeiner Kallweit dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); 953b8f5fe3bSHeiner Kallweit if (!dr) 954b8f5fe3bSHeiner Kallweit return ERR_PTR(-ENOMEM); 955b8f5fe3bSHeiner Kallweit 956b8f5fe3bSHeiner Kallweit client = i2c_new_dummy_device(adapter, address); 957b8f5fe3bSHeiner Kallweit if (IS_ERR(client)) { 958b8f5fe3bSHeiner Kallweit devres_free(dr); 959b8f5fe3bSHeiner Kallweit } else { 960b8f5fe3bSHeiner Kallweit dr->client = client; 961b8f5fe3bSHeiner Kallweit devres_add(dev, dr); 962b8f5fe3bSHeiner Kallweit } 963b8f5fe3bSHeiner Kallweit 964b8f5fe3bSHeiner Kallweit return client; 965b8f5fe3bSHeiner Kallweit } 966b8f5fe3bSHeiner Kallweit EXPORT_SYMBOL_GPL(devm_i2c_new_dummy_device); 967b8f5fe3bSHeiner Kallweit 96891ed5349SWolfram Sang /** 96991ed5349SWolfram Sang * i2c_new_secondary_device - Helper to get the instantiated secondary address 97091ed5349SWolfram Sang * and create the associated device 97191ed5349SWolfram Sang * @client: Handle to the primary client 97291ed5349SWolfram Sang * @name: Handle to specify which secondary address to get 97391ed5349SWolfram Sang * @default_addr: Used as a fallback if no secondary address was specified 97491ed5349SWolfram Sang * Context: can sleep 97591ed5349SWolfram Sang * 97691ed5349SWolfram Sang * I2C clients can be composed of multiple I2C slaves bound together in a single 97791ed5349SWolfram Sang * component. The I2C client driver then binds to the master I2C slave and needs 97891ed5349SWolfram Sang * to create I2C dummy clients to communicate with all the other slaves. 97991ed5349SWolfram Sang * 98091ed5349SWolfram Sang * This function creates and returns an I2C dummy client whose I2C address is 98191ed5349SWolfram Sang * retrieved from the platform firmware based on the given slave name. If no 98291ed5349SWolfram Sang * address is specified by the firmware default_addr is used. 98391ed5349SWolfram Sang * 98491ed5349SWolfram Sang * On DT-based platforms the address is retrieved from the "reg" property entry 98591ed5349SWolfram Sang * cell whose "reg-names" value matches the slave name. 98691ed5349SWolfram Sang * 98791ed5349SWolfram Sang * This returns the new i2c client, which should be saved for later use with 98891ed5349SWolfram Sang * i2c_unregister_device(); or NULL to indicate an error. 98991ed5349SWolfram Sang */ 99091ed5349SWolfram Sang struct i2c_client *i2c_new_secondary_device(struct i2c_client *client, 99191ed5349SWolfram Sang const char *name, 99291ed5349SWolfram Sang u16 default_addr) 99391ed5349SWolfram Sang { 99491ed5349SWolfram Sang struct device_node *np = client->dev.of_node; 99591ed5349SWolfram Sang u32 addr = default_addr; 99691ed5349SWolfram Sang int i; 99791ed5349SWolfram Sang 99891ed5349SWolfram Sang if (np) { 99991ed5349SWolfram Sang i = of_property_match_string(np, "reg-names", name); 100091ed5349SWolfram Sang if (i >= 0) 100191ed5349SWolfram Sang of_property_read_u32_index(np, "reg", i, &addr); 100291ed5349SWolfram Sang } 100391ed5349SWolfram Sang 100491ed5349SWolfram Sang dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); 100591ed5349SWolfram Sang return i2c_new_dummy(client->adapter, addr); 100691ed5349SWolfram Sang } 100791ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_secondary_device); 100891ed5349SWolfram Sang 100991ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 101091ed5349SWolfram Sang 101191ed5349SWolfram Sang /* I2C bus adapters -- one roots each I2C or SMBUS segment */ 101291ed5349SWolfram Sang 101391ed5349SWolfram Sang static void i2c_adapter_dev_release(struct device *dev) 101491ed5349SWolfram Sang { 101591ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 101691ed5349SWolfram Sang complete(&adap->dev_released); 101791ed5349SWolfram Sang } 101891ed5349SWolfram Sang 101991ed5349SWolfram Sang unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) 102091ed5349SWolfram Sang { 102191ed5349SWolfram Sang unsigned int depth = 0; 102291ed5349SWolfram Sang 102391ed5349SWolfram Sang while ((adapter = i2c_parent_is_i2c_adapter(adapter))) 102491ed5349SWolfram Sang depth++; 102591ed5349SWolfram Sang 102691ed5349SWolfram Sang WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES, 102791ed5349SWolfram Sang "adapter depth exceeds lockdep subclass limit\n"); 102891ed5349SWolfram Sang 102991ed5349SWolfram Sang return depth; 103091ed5349SWolfram Sang } 103191ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_adapter_depth); 103291ed5349SWolfram Sang 103391ed5349SWolfram Sang /* 103491ed5349SWolfram Sang * Let users instantiate I2C devices through sysfs. This can be used when 103591ed5349SWolfram Sang * platform initialization code doesn't contain the proper data for 103691ed5349SWolfram Sang * whatever reason. Also useful for drivers that do device detection and 103791ed5349SWolfram Sang * detection fails, either because the device uses an unexpected address, 103891ed5349SWolfram Sang * or this is a compatible device with different ID register values. 103991ed5349SWolfram Sang * 104091ed5349SWolfram Sang * Parameter checking may look overzealous, but we really don't want 104191ed5349SWolfram Sang * the user to provide incorrect parameters. 104291ed5349SWolfram Sang */ 104391ed5349SWolfram Sang static ssize_t 104491ed5349SWolfram Sang i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, 104591ed5349SWolfram Sang const char *buf, size_t count) 104691ed5349SWolfram Sang { 104791ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 104891ed5349SWolfram Sang struct i2c_board_info info; 104991ed5349SWolfram Sang struct i2c_client *client; 105091ed5349SWolfram Sang char *blank, end; 105191ed5349SWolfram Sang int res; 105291ed5349SWolfram Sang 105391ed5349SWolfram Sang memset(&info, 0, sizeof(struct i2c_board_info)); 105491ed5349SWolfram Sang 105591ed5349SWolfram Sang blank = strchr(buf, ' '); 105691ed5349SWolfram Sang if (!blank) { 105791ed5349SWolfram Sang dev_err(dev, "%s: Missing parameters\n", "new_device"); 105891ed5349SWolfram Sang return -EINVAL; 105991ed5349SWolfram Sang } 106091ed5349SWolfram Sang if (blank - buf > I2C_NAME_SIZE - 1) { 106191ed5349SWolfram Sang dev_err(dev, "%s: Invalid device name\n", "new_device"); 106291ed5349SWolfram Sang return -EINVAL; 106391ed5349SWolfram Sang } 106491ed5349SWolfram Sang memcpy(info.type, buf, blank - buf); 106591ed5349SWolfram Sang 106691ed5349SWolfram Sang /* Parse remaining parameters, reject extra parameters */ 106791ed5349SWolfram Sang res = sscanf(++blank, "%hi%c", &info.addr, &end); 106891ed5349SWolfram Sang if (res < 1) { 106991ed5349SWolfram Sang dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); 107091ed5349SWolfram Sang return -EINVAL; 107191ed5349SWolfram Sang } 107291ed5349SWolfram Sang if (res > 1 && end != '\n') { 107391ed5349SWolfram Sang dev_err(dev, "%s: Extra parameters\n", "new_device"); 107491ed5349SWolfram Sang return -EINVAL; 107591ed5349SWolfram Sang } 107691ed5349SWolfram Sang 107791ed5349SWolfram Sang if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { 107891ed5349SWolfram Sang info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; 107991ed5349SWolfram Sang info.flags |= I2C_CLIENT_TEN; 108091ed5349SWolfram Sang } 108191ed5349SWolfram Sang 108291ed5349SWolfram Sang if (info.addr & I2C_ADDR_OFFSET_SLAVE) { 108391ed5349SWolfram Sang info.addr &= ~I2C_ADDR_OFFSET_SLAVE; 108491ed5349SWolfram Sang info.flags |= I2C_CLIENT_SLAVE; 108591ed5349SWolfram Sang } 108691ed5349SWolfram Sang 10877159dbdaSHeiner Kallweit client = i2c_new_client_device(adap, &info); 10887159dbdaSHeiner Kallweit if (IS_ERR(client)) 10897159dbdaSHeiner Kallweit return PTR_ERR(client); 109091ed5349SWolfram Sang 109191ed5349SWolfram Sang /* Keep track of the added device */ 109291ed5349SWolfram Sang mutex_lock(&adap->userspace_clients_lock); 109391ed5349SWolfram Sang list_add_tail(&client->detected, &adap->userspace_clients); 109491ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 109591ed5349SWolfram Sang dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", 109691ed5349SWolfram Sang info.type, info.addr); 109791ed5349SWolfram Sang 109891ed5349SWolfram Sang return count; 109991ed5349SWolfram Sang } 110091ed5349SWolfram Sang static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); 110191ed5349SWolfram Sang 110291ed5349SWolfram Sang /* 110391ed5349SWolfram Sang * And of course let the users delete the devices they instantiated, if 110491ed5349SWolfram Sang * they got it wrong. This interface can only be used to delete devices 110591ed5349SWolfram Sang * instantiated by i2c_sysfs_new_device above. This guarantees that we 110691ed5349SWolfram Sang * don't delete devices to which some kernel code still has references. 110791ed5349SWolfram Sang * 110891ed5349SWolfram Sang * Parameter checking may look overzealous, but we really don't want 110991ed5349SWolfram Sang * the user to delete the wrong device. 111091ed5349SWolfram Sang */ 111191ed5349SWolfram Sang static ssize_t 111291ed5349SWolfram Sang i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, 111391ed5349SWolfram Sang const char *buf, size_t count) 111491ed5349SWolfram Sang { 111591ed5349SWolfram Sang struct i2c_adapter *adap = to_i2c_adapter(dev); 111691ed5349SWolfram Sang struct i2c_client *client, *next; 111791ed5349SWolfram Sang unsigned short addr; 111891ed5349SWolfram Sang char end; 111991ed5349SWolfram Sang int res; 112091ed5349SWolfram Sang 112191ed5349SWolfram Sang /* Parse parameters, reject extra parameters */ 112291ed5349SWolfram Sang res = sscanf(buf, "%hi%c", &addr, &end); 112391ed5349SWolfram Sang if (res < 1) { 112491ed5349SWolfram Sang dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); 112591ed5349SWolfram Sang return -EINVAL; 112691ed5349SWolfram Sang } 112791ed5349SWolfram Sang if (res > 1 && end != '\n') { 112891ed5349SWolfram Sang dev_err(dev, "%s: Extra parameters\n", "delete_device"); 112991ed5349SWolfram Sang return -EINVAL; 113091ed5349SWolfram Sang } 113191ed5349SWolfram Sang 113291ed5349SWolfram Sang /* Make sure the device was added through sysfs */ 113391ed5349SWolfram Sang res = -ENOENT; 113491ed5349SWolfram Sang mutex_lock_nested(&adap->userspace_clients_lock, 113591ed5349SWolfram Sang i2c_adapter_depth(adap)); 113691ed5349SWolfram Sang list_for_each_entry_safe(client, next, &adap->userspace_clients, 113791ed5349SWolfram Sang detected) { 113891ed5349SWolfram Sang if (i2c_encode_flags_to_addr(client) == addr) { 113991ed5349SWolfram Sang dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", 114091ed5349SWolfram Sang "delete_device", client->name, client->addr); 114191ed5349SWolfram Sang 114291ed5349SWolfram Sang list_del(&client->detected); 114391ed5349SWolfram Sang i2c_unregister_device(client); 114491ed5349SWolfram Sang res = count; 114591ed5349SWolfram Sang break; 114691ed5349SWolfram Sang } 114791ed5349SWolfram Sang } 114891ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 114991ed5349SWolfram Sang 115091ed5349SWolfram Sang if (res < 0) 115191ed5349SWolfram Sang dev_err(dev, "%s: Can't find device in list\n", 115291ed5349SWolfram Sang "delete_device"); 115391ed5349SWolfram Sang return res; 115491ed5349SWolfram Sang } 115591ed5349SWolfram Sang static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, 115691ed5349SWolfram Sang i2c_sysfs_delete_device); 115791ed5349SWolfram Sang 115891ed5349SWolfram Sang static struct attribute *i2c_adapter_attrs[] = { 115991ed5349SWolfram Sang &dev_attr_name.attr, 116091ed5349SWolfram Sang &dev_attr_new_device.attr, 116191ed5349SWolfram Sang &dev_attr_delete_device.attr, 116291ed5349SWolfram Sang NULL 116391ed5349SWolfram Sang }; 116491ed5349SWolfram Sang ATTRIBUTE_GROUPS(i2c_adapter); 116591ed5349SWolfram Sang 116691ed5349SWolfram Sang struct device_type i2c_adapter_type = { 116791ed5349SWolfram Sang .groups = i2c_adapter_groups, 116891ed5349SWolfram Sang .release = i2c_adapter_dev_release, 116991ed5349SWolfram Sang }; 117091ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_adapter_type); 117191ed5349SWolfram Sang 117291ed5349SWolfram Sang /** 117391ed5349SWolfram Sang * i2c_verify_adapter - return parameter as i2c_adapter or NULL 117491ed5349SWolfram Sang * @dev: device, probably from some driver model iterator 117591ed5349SWolfram Sang * 117691ed5349SWolfram Sang * When traversing the driver model tree, perhaps using driver model 117791ed5349SWolfram Sang * iterators like @device_for_each_child(), you can't assume very much 117891ed5349SWolfram Sang * about the nodes you find. Use this function to avoid oopses caused 117991ed5349SWolfram Sang * by wrongly treating some non-I2C device as an i2c_adapter. 118091ed5349SWolfram Sang */ 118191ed5349SWolfram Sang struct i2c_adapter *i2c_verify_adapter(struct device *dev) 118291ed5349SWolfram Sang { 118391ed5349SWolfram Sang return (dev->type == &i2c_adapter_type) 118491ed5349SWolfram Sang ? to_i2c_adapter(dev) 118591ed5349SWolfram Sang : NULL; 118691ed5349SWolfram Sang } 118791ed5349SWolfram Sang EXPORT_SYMBOL(i2c_verify_adapter); 118891ed5349SWolfram Sang 118991ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 119091ed5349SWolfram Sang static struct class_compat *i2c_adapter_compat_class; 119191ed5349SWolfram Sang #endif 119291ed5349SWolfram Sang 119391ed5349SWolfram Sang static void i2c_scan_static_board_info(struct i2c_adapter *adapter) 119491ed5349SWolfram Sang { 119591ed5349SWolfram Sang struct i2c_devinfo *devinfo; 119691ed5349SWolfram Sang 119791ed5349SWolfram Sang down_read(&__i2c_board_lock); 119891ed5349SWolfram Sang list_for_each_entry(devinfo, &__i2c_board_list, list) { 119991ed5349SWolfram Sang if (devinfo->busnum == adapter->nr 120091ed5349SWolfram Sang && !i2c_new_device(adapter, 120191ed5349SWolfram Sang &devinfo->board_info)) 120291ed5349SWolfram Sang dev_err(&adapter->dev, 120391ed5349SWolfram Sang "Can't create device at 0x%02x\n", 120491ed5349SWolfram Sang devinfo->board_info.addr); 120591ed5349SWolfram Sang } 120691ed5349SWolfram Sang up_read(&__i2c_board_lock); 120791ed5349SWolfram Sang } 120891ed5349SWolfram Sang 120991ed5349SWolfram Sang static int i2c_do_add_adapter(struct i2c_driver *driver, 121091ed5349SWolfram Sang struct i2c_adapter *adap) 121191ed5349SWolfram Sang { 121291ed5349SWolfram Sang /* Detect supported devices on that bus, and instantiate them */ 121391ed5349SWolfram Sang i2c_detect(adap, driver); 121491ed5349SWolfram Sang 121591ed5349SWolfram Sang return 0; 121691ed5349SWolfram Sang } 121791ed5349SWolfram Sang 121891ed5349SWolfram Sang static int __process_new_adapter(struct device_driver *d, void *data) 121991ed5349SWolfram Sang { 122091ed5349SWolfram Sang return i2c_do_add_adapter(to_i2c_driver(d), data); 122191ed5349SWolfram Sang } 122291ed5349SWolfram Sang 122391ed5349SWolfram Sang static const struct i2c_lock_operations i2c_adapter_lock_ops = { 122491ed5349SWolfram Sang .lock_bus = i2c_adapter_lock_bus, 122591ed5349SWolfram Sang .trylock_bus = i2c_adapter_trylock_bus, 122691ed5349SWolfram Sang .unlock_bus = i2c_adapter_unlock_bus, 122791ed5349SWolfram Sang }; 122891ed5349SWolfram Sang 122991ed5349SWolfram Sang static void i2c_host_notify_irq_teardown(struct i2c_adapter *adap) 123091ed5349SWolfram Sang { 123191ed5349SWolfram Sang struct irq_domain *domain = adap->host_notify_domain; 123291ed5349SWolfram Sang irq_hw_number_t hwirq; 123391ed5349SWolfram Sang 123491ed5349SWolfram Sang if (!domain) 123591ed5349SWolfram Sang return; 123691ed5349SWolfram Sang 123791ed5349SWolfram Sang for (hwirq = 0 ; hwirq < I2C_ADDR_7BITS_COUNT ; hwirq++) 123891ed5349SWolfram Sang irq_dispose_mapping(irq_find_mapping(domain, hwirq)); 123991ed5349SWolfram Sang 124091ed5349SWolfram Sang irq_domain_remove(domain); 124191ed5349SWolfram Sang adap->host_notify_domain = NULL; 124291ed5349SWolfram Sang } 124391ed5349SWolfram Sang 124491ed5349SWolfram Sang static int i2c_host_notify_irq_map(struct irq_domain *h, 124591ed5349SWolfram Sang unsigned int virq, 124691ed5349SWolfram Sang irq_hw_number_t hw_irq_num) 124791ed5349SWolfram Sang { 124891ed5349SWolfram Sang irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); 124991ed5349SWolfram Sang 125091ed5349SWolfram Sang return 0; 125191ed5349SWolfram Sang } 125291ed5349SWolfram Sang 125391ed5349SWolfram Sang static const struct irq_domain_ops i2c_host_notify_irq_ops = { 125491ed5349SWolfram Sang .map = i2c_host_notify_irq_map, 125591ed5349SWolfram Sang }; 125691ed5349SWolfram Sang 125791ed5349SWolfram Sang static int i2c_setup_host_notify_irq_domain(struct i2c_adapter *adap) 125891ed5349SWolfram Sang { 125991ed5349SWolfram Sang struct irq_domain *domain; 126091ed5349SWolfram Sang 126191ed5349SWolfram Sang if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_HOST_NOTIFY)) 126291ed5349SWolfram Sang return 0; 126391ed5349SWolfram Sang 126491ed5349SWolfram Sang domain = irq_domain_create_linear(adap->dev.fwnode, 126591ed5349SWolfram Sang I2C_ADDR_7BITS_COUNT, 126691ed5349SWolfram Sang &i2c_host_notify_irq_ops, adap); 126791ed5349SWolfram Sang if (!domain) 126891ed5349SWolfram Sang return -ENOMEM; 126991ed5349SWolfram Sang 127091ed5349SWolfram Sang adap->host_notify_domain = domain; 127191ed5349SWolfram Sang 127291ed5349SWolfram Sang return 0; 127391ed5349SWolfram Sang } 127491ed5349SWolfram Sang 127591ed5349SWolfram Sang /** 127691ed5349SWolfram Sang * i2c_handle_smbus_host_notify - Forward a Host Notify event to the correct 127791ed5349SWolfram Sang * I2C client. 127891ed5349SWolfram Sang * @adap: the adapter 127991ed5349SWolfram Sang * @addr: the I2C address of the notifying device 128091ed5349SWolfram Sang * Context: can't sleep 128191ed5349SWolfram Sang * 128291ed5349SWolfram Sang * Helper function to be called from an I2C bus driver's interrupt 128391ed5349SWolfram Sang * handler. It will schedule the Host Notify IRQ. 128491ed5349SWolfram Sang */ 128591ed5349SWolfram Sang int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr) 128691ed5349SWolfram Sang { 128791ed5349SWolfram Sang int irq; 128891ed5349SWolfram Sang 128991ed5349SWolfram Sang if (!adap) 129091ed5349SWolfram Sang return -EINVAL; 129191ed5349SWolfram Sang 129291ed5349SWolfram Sang irq = irq_find_mapping(adap->host_notify_domain, addr); 129391ed5349SWolfram Sang if (irq <= 0) 129491ed5349SWolfram Sang return -ENXIO; 129591ed5349SWolfram Sang 129691ed5349SWolfram Sang generic_handle_irq(irq); 129791ed5349SWolfram Sang 129891ed5349SWolfram Sang return 0; 129991ed5349SWolfram Sang } 130091ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify); 130191ed5349SWolfram Sang 130291ed5349SWolfram Sang static int i2c_register_adapter(struct i2c_adapter *adap) 130391ed5349SWolfram Sang { 130491ed5349SWolfram Sang int res = -EINVAL; 130591ed5349SWolfram Sang 130691ed5349SWolfram Sang /* Can't register until after driver model init */ 130791ed5349SWolfram Sang if (WARN_ON(!is_registered)) { 130891ed5349SWolfram Sang res = -EAGAIN; 130991ed5349SWolfram Sang goto out_list; 131091ed5349SWolfram Sang } 131191ed5349SWolfram Sang 131291ed5349SWolfram Sang /* Sanity checks */ 131391ed5349SWolfram Sang if (WARN(!adap->name[0], "i2c adapter has no name")) 131491ed5349SWolfram Sang goto out_list; 131591ed5349SWolfram Sang 131691ed5349SWolfram Sang if (!adap->algo) { 131791ed5349SWolfram Sang pr_err("adapter '%s': no algo supplied!\n", adap->name); 131891ed5349SWolfram Sang goto out_list; 131991ed5349SWolfram Sang } 132091ed5349SWolfram Sang 132191ed5349SWolfram Sang if (!adap->lock_ops) 132291ed5349SWolfram Sang adap->lock_ops = &i2c_adapter_lock_ops; 132391ed5349SWolfram Sang 13249ac6cb5fSWolfram Sang adap->locked_flags = 0; 132591ed5349SWolfram Sang rt_mutex_init(&adap->bus_lock); 132691ed5349SWolfram Sang rt_mutex_init(&adap->mux_lock); 132791ed5349SWolfram Sang mutex_init(&adap->userspace_clients_lock); 132891ed5349SWolfram Sang INIT_LIST_HEAD(&adap->userspace_clients); 132991ed5349SWolfram Sang 133091ed5349SWolfram Sang /* Set default timeout to 1 second if not already set */ 133191ed5349SWolfram Sang if (adap->timeout == 0) 133291ed5349SWolfram Sang adap->timeout = HZ; 133391ed5349SWolfram Sang 133491ed5349SWolfram Sang /* register soft irqs for Host Notify */ 133591ed5349SWolfram Sang res = i2c_setup_host_notify_irq_domain(adap); 133691ed5349SWolfram Sang if (res) { 133791ed5349SWolfram Sang pr_err("adapter '%s': can't create Host Notify IRQs (%d)\n", 133891ed5349SWolfram Sang adap->name, res); 133991ed5349SWolfram Sang goto out_list; 134091ed5349SWolfram Sang } 134191ed5349SWolfram Sang 134291ed5349SWolfram Sang dev_set_name(&adap->dev, "i2c-%d", adap->nr); 134391ed5349SWolfram Sang adap->dev.bus = &i2c_bus_type; 134491ed5349SWolfram Sang adap->dev.type = &i2c_adapter_type; 134591ed5349SWolfram Sang res = device_register(&adap->dev); 134691ed5349SWolfram Sang if (res) { 134791ed5349SWolfram Sang pr_err("adapter '%s': can't register device (%d)\n", adap->name, res); 134891ed5349SWolfram Sang goto out_list; 134991ed5349SWolfram Sang } 135091ed5349SWolfram Sang 1351f8756c67SPhil Reid res = of_i2c_setup_smbus_alert(adap); 1352f8756c67SPhil Reid if (res) 1353f8756c67SPhil Reid goto out_reg; 1354f8756c67SPhil Reid 135591ed5349SWolfram Sang dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); 135691ed5349SWolfram Sang 135791ed5349SWolfram Sang pm_runtime_no_callbacks(&adap->dev); 135891ed5349SWolfram Sang pm_suspend_ignore_children(&adap->dev, true); 135991ed5349SWolfram Sang pm_runtime_enable(&adap->dev); 136091ed5349SWolfram Sang 136191ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 136291ed5349SWolfram Sang res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, 136391ed5349SWolfram Sang adap->dev.parent); 136491ed5349SWolfram Sang if (res) 136591ed5349SWolfram Sang dev_warn(&adap->dev, 136691ed5349SWolfram Sang "Failed to create compatibility class link\n"); 136791ed5349SWolfram Sang #endif 136891ed5349SWolfram Sang 136991ed5349SWolfram Sang i2c_init_recovery(adap); 137091ed5349SWolfram Sang 137191ed5349SWolfram Sang /* create pre-declared device nodes */ 137291ed5349SWolfram Sang of_i2c_register_devices(adap); 137391ed5349SWolfram Sang i2c_acpi_register_devices(adap); 137491ed5349SWolfram Sang i2c_acpi_install_space_handler(adap); 137591ed5349SWolfram Sang 137691ed5349SWolfram Sang if (adap->nr < __i2c_first_dynamic_bus_num) 137791ed5349SWolfram Sang i2c_scan_static_board_info(adap); 137891ed5349SWolfram Sang 137991ed5349SWolfram Sang /* Notify drivers */ 138091ed5349SWolfram Sang mutex_lock(&core_lock); 138191ed5349SWolfram Sang bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); 138291ed5349SWolfram Sang mutex_unlock(&core_lock); 138391ed5349SWolfram Sang 138491ed5349SWolfram Sang return 0; 138591ed5349SWolfram Sang 1386f8756c67SPhil Reid out_reg: 1387f8756c67SPhil Reid init_completion(&adap->dev_released); 1388f8756c67SPhil Reid device_unregister(&adap->dev); 1389f8756c67SPhil Reid wait_for_completion(&adap->dev_released); 139091ed5349SWolfram Sang out_list: 139191ed5349SWolfram Sang mutex_lock(&core_lock); 139291ed5349SWolfram Sang idr_remove(&i2c_adapter_idr, adap->nr); 139391ed5349SWolfram Sang mutex_unlock(&core_lock); 139491ed5349SWolfram Sang return res; 139591ed5349SWolfram Sang } 139691ed5349SWolfram Sang 139791ed5349SWolfram Sang /** 139891ed5349SWolfram Sang * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 139991ed5349SWolfram Sang * @adap: the adapter to register (with adap->nr initialized) 140091ed5349SWolfram Sang * Context: can sleep 140191ed5349SWolfram Sang * 140291ed5349SWolfram Sang * See i2c_add_numbered_adapter() for details. 140391ed5349SWolfram Sang */ 140491ed5349SWolfram Sang static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) 140591ed5349SWolfram Sang { 140691ed5349SWolfram Sang int id; 140791ed5349SWolfram Sang 140891ed5349SWolfram Sang mutex_lock(&core_lock); 140991ed5349SWolfram Sang id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); 141091ed5349SWolfram Sang mutex_unlock(&core_lock); 141191ed5349SWolfram Sang if (WARN(id < 0, "couldn't get idr")) 141291ed5349SWolfram Sang return id == -ENOSPC ? -EBUSY : id; 141391ed5349SWolfram Sang 141491ed5349SWolfram Sang return i2c_register_adapter(adap); 141591ed5349SWolfram Sang } 141691ed5349SWolfram Sang 141791ed5349SWolfram Sang /** 141891ed5349SWolfram Sang * i2c_add_adapter - declare i2c adapter, use dynamic bus number 141991ed5349SWolfram Sang * @adapter: the adapter to add 142091ed5349SWolfram Sang * Context: can sleep 142191ed5349SWolfram Sang * 142291ed5349SWolfram Sang * This routine is used to declare an I2C adapter when its bus number 142391ed5349SWolfram Sang * doesn't matter or when its bus number is specified by an dt alias. 142491ed5349SWolfram Sang * Examples of bases when the bus number doesn't matter: I2C adapters 142591ed5349SWolfram Sang * dynamically added by USB links or PCI plugin cards. 142691ed5349SWolfram Sang * 142791ed5349SWolfram Sang * When this returns zero, a new bus number was allocated and stored 142891ed5349SWolfram Sang * in adap->nr, and the specified adapter became available for clients. 142991ed5349SWolfram Sang * Otherwise, a negative errno value is returned. 143091ed5349SWolfram Sang */ 143191ed5349SWolfram Sang int i2c_add_adapter(struct i2c_adapter *adapter) 143291ed5349SWolfram Sang { 143391ed5349SWolfram Sang struct device *dev = &adapter->dev; 143491ed5349SWolfram Sang int id; 143591ed5349SWolfram Sang 143691ed5349SWolfram Sang if (dev->of_node) { 143791ed5349SWolfram Sang id = of_alias_get_id(dev->of_node, "i2c"); 143891ed5349SWolfram Sang if (id >= 0) { 143991ed5349SWolfram Sang adapter->nr = id; 144091ed5349SWolfram Sang return __i2c_add_numbered_adapter(adapter); 144191ed5349SWolfram Sang } 144291ed5349SWolfram Sang } 144391ed5349SWolfram Sang 144491ed5349SWolfram Sang mutex_lock(&core_lock); 144591ed5349SWolfram Sang id = idr_alloc(&i2c_adapter_idr, adapter, 144691ed5349SWolfram Sang __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); 144791ed5349SWolfram Sang mutex_unlock(&core_lock); 144891ed5349SWolfram Sang if (WARN(id < 0, "couldn't get idr")) 144991ed5349SWolfram Sang return id; 145091ed5349SWolfram Sang 145191ed5349SWolfram Sang adapter->nr = id; 145291ed5349SWolfram Sang 145391ed5349SWolfram Sang return i2c_register_adapter(adapter); 145491ed5349SWolfram Sang } 145591ed5349SWolfram Sang EXPORT_SYMBOL(i2c_add_adapter); 145691ed5349SWolfram Sang 145791ed5349SWolfram Sang /** 145891ed5349SWolfram Sang * i2c_add_numbered_adapter - declare i2c adapter, use static bus number 145991ed5349SWolfram Sang * @adap: the adapter to register (with adap->nr initialized) 146091ed5349SWolfram Sang * Context: can sleep 146191ed5349SWolfram Sang * 146291ed5349SWolfram Sang * This routine is used to declare an I2C adapter when its bus number 146391ed5349SWolfram Sang * matters. For example, use it for I2C adapters from system-on-chip CPUs, 146491ed5349SWolfram Sang * or otherwise built in to the system's mainboard, and where i2c_board_info 146591ed5349SWolfram Sang * is used to properly configure I2C devices. 146691ed5349SWolfram Sang * 146791ed5349SWolfram Sang * If the requested bus number is set to -1, then this function will behave 146891ed5349SWolfram Sang * identically to i2c_add_adapter, and will dynamically assign a bus number. 146991ed5349SWolfram Sang * 147091ed5349SWolfram Sang * If no devices have pre-been declared for this bus, then be sure to 147191ed5349SWolfram Sang * register the adapter before any dynamically allocated ones. Otherwise 147291ed5349SWolfram Sang * the required bus ID may not be available. 147391ed5349SWolfram Sang * 147491ed5349SWolfram Sang * When this returns zero, the specified adapter became available for 147591ed5349SWolfram Sang * clients using the bus number provided in adap->nr. Also, the table 147691ed5349SWolfram Sang * of I2C devices pre-declared using i2c_register_board_info() is scanned, 147791ed5349SWolfram Sang * and the appropriate driver model device nodes are created. Otherwise, a 147891ed5349SWolfram Sang * negative errno value is returned. 147991ed5349SWolfram Sang */ 148091ed5349SWolfram Sang int i2c_add_numbered_adapter(struct i2c_adapter *adap) 148191ed5349SWolfram Sang { 148291ed5349SWolfram Sang if (adap->nr == -1) /* -1 means dynamically assign bus id */ 148391ed5349SWolfram Sang return i2c_add_adapter(adap); 148491ed5349SWolfram Sang 148591ed5349SWolfram Sang return __i2c_add_numbered_adapter(adap); 148691ed5349SWolfram Sang } 148791ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); 148891ed5349SWolfram Sang 148991ed5349SWolfram Sang static void i2c_do_del_adapter(struct i2c_driver *driver, 149091ed5349SWolfram Sang struct i2c_adapter *adapter) 149191ed5349SWolfram Sang { 149291ed5349SWolfram Sang struct i2c_client *client, *_n; 149391ed5349SWolfram Sang 149491ed5349SWolfram Sang /* Remove the devices we created ourselves as the result of hardware 149591ed5349SWolfram Sang * probing (using a driver's detect method) */ 149691ed5349SWolfram Sang list_for_each_entry_safe(client, _n, &driver->clients, detected) { 149791ed5349SWolfram Sang if (client->adapter == adapter) { 149891ed5349SWolfram Sang dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", 149991ed5349SWolfram Sang client->name, client->addr); 150091ed5349SWolfram Sang list_del(&client->detected); 150191ed5349SWolfram Sang i2c_unregister_device(client); 150291ed5349SWolfram Sang } 150391ed5349SWolfram Sang } 150491ed5349SWolfram Sang } 150591ed5349SWolfram Sang 150691ed5349SWolfram Sang static int __unregister_client(struct device *dev, void *dummy) 150791ed5349SWolfram Sang { 150891ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 150991ed5349SWolfram Sang if (client && strcmp(client->name, "dummy")) 151091ed5349SWolfram Sang i2c_unregister_device(client); 151191ed5349SWolfram Sang return 0; 151291ed5349SWolfram Sang } 151391ed5349SWolfram Sang 151491ed5349SWolfram Sang static int __unregister_dummy(struct device *dev, void *dummy) 151591ed5349SWolfram Sang { 151691ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 151791ed5349SWolfram Sang i2c_unregister_device(client); 151891ed5349SWolfram Sang return 0; 151991ed5349SWolfram Sang } 152091ed5349SWolfram Sang 152191ed5349SWolfram Sang static int __process_removed_adapter(struct device_driver *d, void *data) 152291ed5349SWolfram Sang { 152391ed5349SWolfram Sang i2c_do_del_adapter(to_i2c_driver(d), data); 152491ed5349SWolfram Sang return 0; 152591ed5349SWolfram Sang } 152691ed5349SWolfram Sang 152791ed5349SWolfram Sang /** 152891ed5349SWolfram Sang * i2c_del_adapter - unregister I2C adapter 152991ed5349SWolfram Sang * @adap: the adapter being unregistered 153091ed5349SWolfram Sang * Context: can sleep 153191ed5349SWolfram Sang * 153291ed5349SWolfram Sang * This unregisters an I2C adapter which was previously registered 153391ed5349SWolfram Sang * by @i2c_add_adapter or @i2c_add_numbered_adapter. 153491ed5349SWolfram Sang */ 153591ed5349SWolfram Sang void i2c_del_adapter(struct i2c_adapter *adap) 153691ed5349SWolfram Sang { 153791ed5349SWolfram Sang struct i2c_adapter *found; 153891ed5349SWolfram Sang struct i2c_client *client, *next; 153991ed5349SWolfram Sang 154091ed5349SWolfram Sang /* First make sure that this adapter was ever added */ 154191ed5349SWolfram Sang mutex_lock(&core_lock); 154291ed5349SWolfram Sang found = idr_find(&i2c_adapter_idr, adap->nr); 154391ed5349SWolfram Sang mutex_unlock(&core_lock); 154491ed5349SWolfram Sang if (found != adap) { 154591ed5349SWolfram Sang pr_debug("attempting to delete unregistered adapter [%s]\n", adap->name); 154691ed5349SWolfram Sang return; 154791ed5349SWolfram Sang } 154891ed5349SWolfram Sang 154991ed5349SWolfram Sang i2c_acpi_remove_space_handler(adap); 155091ed5349SWolfram Sang /* Tell drivers about this removal */ 155191ed5349SWolfram Sang mutex_lock(&core_lock); 155291ed5349SWolfram Sang bus_for_each_drv(&i2c_bus_type, NULL, adap, 155391ed5349SWolfram Sang __process_removed_adapter); 155491ed5349SWolfram Sang mutex_unlock(&core_lock); 155591ed5349SWolfram Sang 155691ed5349SWolfram Sang /* Remove devices instantiated from sysfs */ 155791ed5349SWolfram Sang mutex_lock_nested(&adap->userspace_clients_lock, 155891ed5349SWolfram Sang i2c_adapter_depth(adap)); 155991ed5349SWolfram Sang list_for_each_entry_safe(client, next, &adap->userspace_clients, 156091ed5349SWolfram Sang detected) { 156191ed5349SWolfram Sang dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, 156291ed5349SWolfram Sang client->addr); 156391ed5349SWolfram Sang list_del(&client->detected); 156491ed5349SWolfram Sang i2c_unregister_device(client); 156591ed5349SWolfram Sang } 156691ed5349SWolfram Sang mutex_unlock(&adap->userspace_clients_lock); 156791ed5349SWolfram Sang 156891ed5349SWolfram Sang /* Detach any active clients. This can't fail, thus we do not 156991ed5349SWolfram Sang * check the returned value. This is a two-pass process, because 157091ed5349SWolfram Sang * we can't remove the dummy devices during the first pass: they 157191ed5349SWolfram Sang * could have been instantiated by real devices wishing to clean 157291ed5349SWolfram Sang * them up properly, so we give them a chance to do that first. */ 157391ed5349SWolfram Sang device_for_each_child(&adap->dev, NULL, __unregister_client); 157491ed5349SWolfram Sang device_for_each_child(&adap->dev, NULL, __unregister_dummy); 157591ed5349SWolfram Sang 157691ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 157791ed5349SWolfram Sang class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, 157891ed5349SWolfram Sang adap->dev.parent); 157991ed5349SWolfram Sang #endif 158091ed5349SWolfram Sang 158191ed5349SWolfram Sang /* device name is gone after device_unregister */ 158291ed5349SWolfram Sang dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); 158391ed5349SWolfram Sang 158491ed5349SWolfram Sang pm_runtime_disable(&adap->dev); 158591ed5349SWolfram Sang 158691ed5349SWolfram Sang i2c_host_notify_irq_teardown(adap); 158791ed5349SWolfram Sang 158891ed5349SWolfram Sang /* wait until all references to the device are gone 158991ed5349SWolfram Sang * 159091ed5349SWolfram Sang * FIXME: This is old code and should ideally be replaced by an 159191ed5349SWolfram Sang * alternative which results in decoupling the lifetime of the struct 159291ed5349SWolfram Sang * device from the i2c_adapter, like spi or netdev do. Any solution 159391ed5349SWolfram Sang * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! 159491ed5349SWolfram Sang */ 159591ed5349SWolfram Sang init_completion(&adap->dev_released); 159691ed5349SWolfram Sang device_unregister(&adap->dev); 159791ed5349SWolfram Sang wait_for_completion(&adap->dev_released); 159891ed5349SWolfram Sang 159991ed5349SWolfram Sang /* free bus id */ 160091ed5349SWolfram Sang mutex_lock(&core_lock); 160191ed5349SWolfram Sang idr_remove(&i2c_adapter_idr, adap->nr); 160291ed5349SWolfram Sang mutex_unlock(&core_lock); 160391ed5349SWolfram Sang 160491ed5349SWolfram Sang /* Clear the device structure in case this adapter is ever going to be 160591ed5349SWolfram Sang added again */ 160691ed5349SWolfram Sang memset(&adap->dev, 0, sizeof(adap->dev)); 160791ed5349SWolfram Sang } 160891ed5349SWolfram Sang EXPORT_SYMBOL(i2c_del_adapter); 160991ed5349SWolfram Sang 161091ed5349SWolfram Sang /** 161191ed5349SWolfram Sang * i2c_parse_fw_timings - get I2C related timing parameters from firmware 161291ed5349SWolfram Sang * @dev: The device to scan for I2C timing properties 161391ed5349SWolfram Sang * @t: the i2c_timings struct to be filled with values 161491ed5349SWolfram Sang * @use_defaults: bool to use sane defaults derived from the I2C specification 161591ed5349SWolfram Sang * when properties are not found, otherwise use 0 161691ed5349SWolfram Sang * 161791ed5349SWolfram Sang * Scan the device for the generic I2C properties describing timing parameters 161891ed5349SWolfram Sang * for the signal and fill the given struct with the results. If a property was 161991ed5349SWolfram Sang * not found and use_defaults was true, then maximum timings are assumed which 162091ed5349SWolfram Sang * are derived from the I2C specification. If use_defaults is not used, the 162191ed5349SWolfram Sang * results will be 0, so drivers can apply their own defaults later. The latter 162291ed5349SWolfram Sang * is mainly intended for avoiding regressions of existing drivers which want 162391ed5349SWolfram Sang * to switch to this function. New drivers almost always should use the defaults. 162491ed5349SWolfram Sang */ 162591ed5349SWolfram Sang 162691ed5349SWolfram Sang void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) 162791ed5349SWolfram Sang { 162891ed5349SWolfram Sang int ret; 162991ed5349SWolfram Sang 163091ed5349SWolfram Sang memset(t, 0, sizeof(*t)); 163191ed5349SWolfram Sang 163291ed5349SWolfram Sang ret = device_property_read_u32(dev, "clock-frequency", &t->bus_freq_hz); 163391ed5349SWolfram Sang if (ret && use_defaults) 163491ed5349SWolfram Sang t->bus_freq_hz = 100000; 163591ed5349SWolfram Sang 163691ed5349SWolfram Sang ret = device_property_read_u32(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns); 163791ed5349SWolfram Sang if (ret && use_defaults) { 163891ed5349SWolfram Sang if (t->bus_freq_hz <= 100000) 163991ed5349SWolfram Sang t->scl_rise_ns = 1000; 164091ed5349SWolfram Sang else if (t->bus_freq_hz <= 400000) 164191ed5349SWolfram Sang t->scl_rise_ns = 300; 164291ed5349SWolfram Sang else 164391ed5349SWolfram Sang t->scl_rise_ns = 120; 164491ed5349SWolfram Sang } 164591ed5349SWolfram Sang 164691ed5349SWolfram Sang ret = device_property_read_u32(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns); 164791ed5349SWolfram Sang if (ret && use_defaults) { 164891ed5349SWolfram Sang if (t->bus_freq_hz <= 400000) 164991ed5349SWolfram Sang t->scl_fall_ns = 300; 165091ed5349SWolfram Sang else 165191ed5349SWolfram Sang t->scl_fall_ns = 120; 165291ed5349SWolfram Sang } 165391ed5349SWolfram Sang 165491ed5349SWolfram Sang device_property_read_u32(dev, "i2c-scl-internal-delay-ns", &t->scl_int_delay_ns); 165591ed5349SWolfram Sang 165691ed5349SWolfram Sang ret = device_property_read_u32(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns); 165791ed5349SWolfram Sang if (ret && use_defaults) 165891ed5349SWolfram Sang t->sda_fall_ns = t->scl_fall_ns; 16594717be73SAndy Shevchenko 16604717be73SAndy Shevchenko device_property_read_u32(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns); 166191ed5349SWolfram Sang } 166291ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); 166391ed5349SWolfram Sang 166491ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 166591ed5349SWolfram Sang 1666edd7a563SWolfram Sang int i2c_for_each_dev(void *data, int (*fn)(struct device *dev, void *data)) 166791ed5349SWolfram Sang { 166891ed5349SWolfram Sang int res; 166991ed5349SWolfram Sang 167091ed5349SWolfram Sang mutex_lock(&core_lock); 167191ed5349SWolfram Sang res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); 167291ed5349SWolfram Sang mutex_unlock(&core_lock); 167391ed5349SWolfram Sang 167491ed5349SWolfram Sang return res; 167591ed5349SWolfram Sang } 167691ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_for_each_dev); 167791ed5349SWolfram Sang 167891ed5349SWolfram Sang static int __process_new_driver(struct device *dev, void *data) 167991ed5349SWolfram Sang { 168091ed5349SWolfram Sang if (dev->type != &i2c_adapter_type) 168191ed5349SWolfram Sang return 0; 168291ed5349SWolfram Sang return i2c_do_add_adapter(data, to_i2c_adapter(dev)); 168391ed5349SWolfram Sang } 168491ed5349SWolfram Sang 168591ed5349SWolfram Sang /* 168691ed5349SWolfram Sang * An i2c_driver is used with one or more i2c_client (device) nodes to access 168791ed5349SWolfram Sang * i2c slave chips, on a bus instance associated with some i2c_adapter. 168891ed5349SWolfram Sang */ 168991ed5349SWolfram Sang 169091ed5349SWolfram Sang int i2c_register_driver(struct module *owner, struct i2c_driver *driver) 169191ed5349SWolfram Sang { 169291ed5349SWolfram Sang int res; 169391ed5349SWolfram Sang 169491ed5349SWolfram Sang /* Can't register until after driver model init */ 169591ed5349SWolfram Sang if (WARN_ON(!is_registered)) 169691ed5349SWolfram Sang return -EAGAIN; 169791ed5349SWolfram Sang 169891ed5349SWolfram Sang /* add the driver to the list of i2c drivers in the driver core */ 169991ed5349SWolfram Sang driver->driver.owner = owner; 170091ed5349SWolfram Sang driver->driver.bus = &i2c_bus_type; 170191ed5349SWolfram Sang INIT_LIST_HEAD(&driver->clients); 170291ed5349SWolfram Sang 170391ed5349SWolfram Sang /* When registration returns, the driver core 170491ed5349SWolfram Sang * will have called probe() for all matching-but-unbound devices. 170591ed5349SWolfram Sang */ 170691ed5349SWolfram Sang res = driver_register(&driver->driver); 170791ed5349SWolfram Sang if (res) 170891ed5349SWolfram Sang return res; 170991ed5349SWolfram Sang 171091ed5349SWolfram Sang pr_debug("driver [%s] registered\n", driver->driver.name); 171191ed5349SWolfram Sang 171291ed5349SWolfram Sang /* Walk the adapters that are already present */ 171391ed5349SWolfram Sang i2c_for_each_dev(driver, __process_new_driver); 171491ed5349SWolfram Sang 171591ed5349SWolfram Sang return 0; 171691ed5349SWolfram Sang } 171791ed5349SWolfram Sang EXPORT_SYMBOL(i2c_register_driver); 171891ed5349SWolfram Sang 171991ed5349SWolfram Sang static int __process_removed_driver(struct device *dev, void *data) 172091ed5349SWolfram Sang { 172191ed5349SWolfram Sang if (dev->type == &i2c_adapter_type) 172291ed5349SWolfram Sang i2c_do_del_adapter(data, to_i2c_adapter(dev)); 172391ed5349SWolfram Sang return 0; 172491ed5349SWolfram Sang } 172591ed5349SWolfram Sang 172691ed5349SWolfram Sang /** 172791ed5349SWolfram Sang * i2c_del_driver - unregister I2C driver 172891ed5349SWolfram Sang * @driver: the driver being unregistered 172991ed5349SWolfram Sang * Context: can sleep 173091ed5349SWolfram Sang */ 173191ed5349SWolfram Sang void i2c_del_driver(struct i2c_driver *driver) 173291ed5349SWolfram Sang { 173391ed5349SWolfram Sang i2c_for_each_dev(driver, __process_removed_driver); 173491ed5349SWolfram Sang 173591ed5349SWolfram Sang driver_unregister(&driver->driver); 173691ed5349SWolfram Sang pr_debug("driver [%s] unregistered\n", driver->driver.name); 173791ed5349SWolfram Sang } 173891ed5349SWolfram Sang EXPORT_SYMBOL(i2c_del_driver); 173991ed5349SWolfram Sang 174091ed5349SWolfram Sang /* ------------------------------------------------------------------------- */ 174191ed5349SWolfram Sang 174291ed5349SWolfram Sang /** 174391ed5349SWolfram Sang * i2c_use_client - increments the reference count of the i2c client structure 174491ed5349SWolfram Sang * @client: the client being referenced 174591ed5349SWolfram Sang * 174691ed5349SWolfram Sang * Each live reference to a client should be refcounted. The driver model does 174791ed5349SWolfram Sang * that automatically as part of driver binding, so that most drivers don't 174891ed5349SWolfram Sang * need to do this explicitly: they hold a reference until they're unbound 174991ed5349SWolfram Sang * from the device. 175091ed5349SWolfram Sang * 175191ed5349SWolfram Sang * A pointer to the client with the incremented reference counter is returned. 175291ed5349SWolfram Sang */ 175391ed5349SWolfram Sang struct i2c_client *i2c_use_client(struct i2c_client *client) 175491ed5349SWolfram Sang { 175591ed5349SWolfram Sang if (client && get_device(&client->dev)) 175691ed5349SWolfram Sang return client; 175791ed5349SWolfram Sang return NULL; 175891ed5349SWolfram Sang } 175991ed5349SWolfram Sang EXPORT_SYMBOL(i2c_use_client); 176091ed5349SWolfram Sang 176191ed5349SWolfram Sang /** 176291ed5349SWolfram Sang * i2c_release_client - release a use of the i2c client structure 176391ed5349SWolfram Sang * @client: the client being no longer referenced 176491ed5349SWolfram Sang * 176591ed5349SWolfram Sang * Must be called when a user of a client is finished with it. 176691ed5349SWolfram Sang */ 176791ed5349SWolfram Sang void i2c_release_client(struct i2c_client *client) 176891ed5349SWolfram Sang { 176991ed5349SWolfram Sang if (client) 177091ed5349SWolfram Sang put_device(&client->dev); 177191ed5349SWolfram Sang } 177291ed5349SWolfram Sang EXPORT_SYMBOL(i2c_release_client); 177391ed5349SWolfram Sang 177491ed5349SWolfram Sang struct i2c_cmd_arg { 177591ed5349SWolfram Sang unsigned cmd; 177691ed5349SWolfram Sang void *arg; 177791ed5349SWolfram Sang }; 177891ed5349SWolfram Sang 177991ed5349SWolfram Sang static int i2c_cmd(struct device *dev, void *_arg) 178091ed5349SWolfram Sang { 178191ed5349SWolfram Sang struct i2c_client *client = i2c_verify_client(dev); 178291ed5349SWolfram Sang struct i2c_cmd_arg *arg = _arg; 178391ed5349SWolfram Sang struct i2c_driver *driver; 178491ed5349SWolfram Sang 178591ed5349SWolfram Sang if (!client || !client->dev.driver) 178691ed5349SWolfram Sang return 0; 178791ed5349SWolfram Sang 178891ed5349SWolfram Sang driver = to_i2c_driver(client->dev.driver); 178991ed5349SWolfram Sang if (driver->command) 179091ed5349SWolfram Sang driver->command(client, arg->cmd, arg->arg); 179191ed5349SWolfram Sang return 0; 179291ed5349SWolfram Sang } 179391ed5349SWolfram Sang 179491ed5349SWolfram Sang void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) 179591ed5349SWolfram Sang { 179691ed5349SWolfram Sang struct i2c_cmd_arg cmd_arg; 179791ed5349SWolfram Sang 179891ed5349SWolfram Sang cmd_arg.cmd = cmd; 179991ed5349SWolfram Sang cmd_arg.arg = arg; 180091ed5349SWolfram Sang device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); 180191ed5349SWolfram Sang } 180291ed5349SWolfram Sang EXPORT_SYMBOL(i2c_clients_command); 180391ed5349SWolfram Sang 180491ed5349SWolfram Sang static int __init i2c_init(void) 180591ed5349SWolfram Sang { 180691ed5349SWolfram Sang int retval; 180791ed5349SWolfram Sang 180891ed5349SWolfram Sang retval = of_alias_get_highest_id("i2c"); 180991ed5349SWolfram Sang 181091ed5349SWolfram Sang down_write(&__i2c_board_lock); 181191ed5349SWolfram Sang if (retval >= __i2c_first_dynamic_bus_num) 181291ed5349SWolfram Sang __i2c_first_dynamic_bus_num = retval + 1; 181391ed5349SWolfram Sang up_write(&__i2c_board_lock); 181491ed5349SWolfram Sang 181591ed5349SWolfram Sang retval = bus_register(&i2c_bus_type); 181691ed5349SWolfram Sang if (retval) 181791ed5349SWolfram Sang return retval; 181891ed5349SWolfram Sang 181991ed5349SWolfram Sang is_registered = true; 182091ed5349SWolfram Sang 182191ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 182291ed5349SWolfram Sang i2c_adapter_compat_class = class_compat_register("i2c-adapter"); 182391ed5349SWolfram Sang if (!i2c_adapter_compat_class) { 182491ed5349SWolfram Sang retval = -ENOMEM; 182591ed5349SWolfram Sang goto bus_err; 182691ed5349SWolfram Sang } 182791ed5349SWolfram Sang #endif 182891ed5349SWolfram Sang retval = i2c_add_driver(&dummy_driver); 182991ed5349SWolfram Sang if (retval) 183091ed5349SWolfram Sang goto class_err; 183191ed5349SWolfram Sang 183291ed5349SWolfram Sang if (IS_ENABLED(CONFIG_OF_DYNAMIC)) 183391ed5349SWolfram Sang WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); 183491ed5349SWolfram Sang if (IS_ENABLED(CONFIG_ACPI)) 183591ed5349SWolfram Sang WARN_ON(acpi_reconfig_notifier_register(&i2c_acpi_notifier)); 183691ed5349SWolfram Sang 183791ed5349SWolfram Sang return 0; 183891ed5349SWolfram Sang 183991ed5349SWolfram Sang class_err: 184091ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 184191ed5349SWolfram Sang class_compat_unregister(i2c_adapter_compat_class); 184291ed5349SWolfram Sang bus_err: 184391ed5349SWolfram Sang #endif 184491ed5349SWolfram Sang is_registered = false; 184591ed5349SWolfram Sang bus_unregister(&i2c_bus_type); 184691ed5349SWolfram Sang return retval; 184791ed5349SWolfram Sang } 184891ed5349SWolfram Sang 184991ed5349SWolfram Sang static void __exit i2c_exit(void) 185091ed5349SWolfram Sang { 185191ed5349SWolfram Sang if (IS_ENABLED(CONFIG_ACPI)) 185291ed5349SWolfram Sang WARN_ON(acpi_reconfig_notifier_unregister(&i2c_acpi_notifier)); 185391ed5349SWolfram Sang if (IS_ENABLED(CONFIG_OF_DYNAMIC)) 185491ed5349SWolfram Sang WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); 185591ed5349SWolfram Sang i2c_del_driver(&dummy_driver); 185691ed5349SWolfram Sang #ifdef CONFIG_I2C_COMPAT 185791ed5349SWolfram Sang class_compat_unregister(i2c_adapter_compat_class); 185891ed5349SWolfram Sang #endif 185991ed5349SWolfram Sang bus_unregister(&i2c_bus_type); 186091ed5349SWolfram Sang tracepoint_synchronize_unregister(); 186191ed5349SWolfram Sang } 186291ed5349SWolfram Sang 186391ed5349SWolfram Sang /* We must initialize early, because some subsystems register i2c drivers 186491ed5349SWolfram Sang * in subsys_initcall() code, but are linked (and initialized) before i2c. 186591ed5349SWolfram Sang */ 186691ed5349SWolfram Sang postcore_initcall(i2c_init); 186791ed5349SWolfram Sang module_exit(i2c_exit); 186891ed5349SWolfram Sang 186991ed5349SWolfram Sang /* ---------------------------------------------------- 187091ed5349SWolfram Sang * the functional interface to the i2c busses. 187191ed5349SWolfram Sang * ---------------------------------------------------- 187291ed5349SWolfram Sang */ 187391ed5349SWolfram Sang 187491ed5349SWolfram Sang /* Check if val is exceeding the quirk IFF quirk is non 0 */ 187591ed5349SWolfram Sang #define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) 187691ed5349SWolfram Sang 187791ed5349SWolfram Sang static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) 187891ed5349SWolfram Sang { 187991ed5349SWolfram Sang dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", 188091ed5349SWolfram Sang err_msg, msg->addr, msg->len, 188191ed5349SWolfram Sang msg->flags & I2C_M_RD ? "read" : "write"); 188291ed5349SWolfram Sang return -EOPNOTSUPP; 188391ed5349SWolfram Sang } 188491ed5349SWolfram Sang 188591ed5349SWolfram Sang static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 188691ed5349SWolfram Sang { 188791ed5349SWolfram Sang const struct i2c_adapter_quirks *q = adap->quirks; 188891ed5349SWolfram Sang int max_num = q->max_num_msgs, i; 188991ed5349SWolfram Sang bool do_len_check = true; 189091ed5349SWolfram Sang 189191ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB) { 189291ed5349SWolfram Sang max_num = 2; 189391ed5349SWolfram Sang 189491ed5349SWolfram Sang /* special checks for combined messages */ 189591ed5349SWolfram Sang if (num == 2) { 189691ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) 189791ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); 189891ed5349SWolfram Sang 189991ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) 190091ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); 190191ed5349SWolfram Sang 190291ed5349SWolfram Sang if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) 190391ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); 190491ed5349SWolfram Sang 190591ed5349SWolfram Sang if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) 190691ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "msg too long"); 190791ed5349SWolfram Sang 190891ed5349SWolfram Sang if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) 190991ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[1], "msg too long"); 191091ed5349SWolfram Sang 191191ed5349SWolfram Sang do_len_check = false; 191291ed5349SWolfram Sang } 191391ed5349SWolfram Sang } 191491ed5349SWolfram Sang 191591ed5349SWolfram Sang if (i2c_quirk_exceeded(num, max_num)) 191691ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[0], "too many messages"); 191791ed5349SWolfram Sang 191891ed5349SWolfram Sang for (i = 0; i < num; i++) { 191991ed5349SWolfram Sang u16 len = msgs[i].len; 192091ed5349SWolfram Sang 192191ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) { 192291ed5349SWolfram Sang if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) 192391ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[i], "msg too long"); 1924d9cfe2ceSWolfram Sang 1925d9cfe2ceSWolfram Sang if (q->flags & I2C_AQ_NO_ZERO_LEN_READ && len == 0) 1926d9cfe2ceSWolfram Sang return i2c_quirk_error(adap, &msgs[i], "no zero length"); 192791ed5349SWolfram Sang } else { 192891ed5349SWolfram Sang if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) 192991ed5349SWolfram Sang return i2c_quirk_error(adap, &msgs[i], "msg too long"); 1930d9cfe2ceSWolfram Sang 1931d9cfe2ceSWolfram Sang if (q->flags & I2C_AQ_NO_ZERO_LEN_WRITE && len == 0) 1932d9cfe2ceSWolfram Sang return i2c_quirk_error(adap, &msgs[i], "no zero length"); 193391ed5349SWolfram Sang } 193491ed5349SWolfram Sang } 193591ed5349SWolfram Sang 193691ed5349SWolfram Sang return 0; 193791ed5349SWolfram Sang } 193891ed5349SWolfram Sang 193991ed5349SWolfram Sang /** 194091ed5349SWolfram Sang * __i2c_transfer - unlocked flavor of i2c_transfer 194191ed5349SWolfram Sang * @adap: Handle to I2C bus 194291ed5349SWolfram Sang * @msgs: One or more messages to execute before STOP is issued to 194391ed5349SWolfram Sang * terminate the operation; each message begins with a START. 194491ed5349SWolfram Sang * @num: Number of messages to be executed. 194591ed5349SWolfram Sang * 194691ed5349SWolfram Sang * Returns negative errno, else the number of messages executed. 194791ed5349SWolfram Sang * 194891ed5349SWolfram Sang * Adapter lock must be held when calling this function. No debug logging 194991ed5349SWolfram Sang * takes place. adap->algo->master_xfer existence isn't checked. 195091ed5349SWolfram Sang */ 195191ed5349SWolfram Sang int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 195291ed5349SWolfram Sang { 195391ed5349SWolfram Sang unsigned long orig_jiffies; 195491ed5349SWolfram Sang int ret, try; 195591ed5349SWolfram Sang 19561eace834SArd Biesheuvel if (WARN_ON(!msgs || num < 1)) 19571eace834SArd Biesheuvel return -EINVAL; 19585d756112SWolfram Sang 19595d756112SWolfram Sang ret = __i2c_check_suspended(adap); 19605d756112SWolfram Sang if (ret) 19615d756112SWolfram Sang return ret; 19621eace834SArd Biesheuvel 196391ed5349SWolfram Sang if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) 196491ed5349SWolfram Sang return -EOPNOTSUPP; 196591ed5349SWolfram Sang 196650888b01SDavidlohr Bueso /* 196750888b01SDavidlohr Bueso * i2c_trace_msg_key gets enabled when tracepoint i2c_transfer gets 196891ed5349SWolfram Sang * enabled. This is an efficient way of keeping the for-loop from 196991ed5349SWolfram Sang * being executed when not needed. 197091ed5349SWolfram Sang */ 197150888b01SDavidlohr Bueso if (static_branch_unlikely(&i2c_trace_msg_key)) { 197291ed5349SWolfram Sang int i; 197391ed5349SWolfram Sang for (i = 0; i < num; i++) 197491ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) 197591ed5349SWolfram Sang trace_i2c_read(adap, &msgs[i], i); 197691ed5349SWolfram Sang else 197791ed5349SWolfram Sang trace_i2c_write(adap, &msgs[i], i); 197891ed5349SWolfram Sang } 197991ed5349SWolfram Sang 198091ed5349SWolfram Sang /* Retry automatically on arbitration loss */ 198191ed5349SWolfram Sang orig_jiffies = jiffies; 198291ed5349SWolfram Sang for (ret = 0, try = 0; try <= adap->retries; try++) { 198363b96983SWolfram Sang if (i2c_in_atomic_xfer_mode() && adap->algo->master_xfer_atomic) 198463b96983SWolfram Sang ret = adap->algo->master_xfer_atomic(adap, msgs, num); 198563b96983SWolfram Sang else 198691ed5349SWolfram Sang ret = adap->algo->master_xfer(adap, msgs, num); 198763b96983SWolfram Sang 198891ed5349SWolfram Sang if (ret != -EAGAIN) 198991ed5349SWolfram Sang break; 199091ed5349SWolfram Sang if (time_after(jiffies, orig_jiffies + adap->timeout)) 199191ed5349SWolfram Sang break; 199291ed5349SWolfram Sang } 199391ed5349SWolfram Sang 199450888b01SDavidlohr Bueso if (static_branch_unlikely(&i2c_trace_msg_key)) { 199591ed5349SWolfram Sang int i; 199691ed5349SWolfram Sang for (i = 0; i < ret; i++) 199791ed5349SWolfram Sang if (msgs[i].flags & I2C_M_RD) 199891ed5349SWolfram Sang trace_i2c_reply(adap, &msgs[i], i); 19994a3f7691SAhbong Chang trace_i2c_result(adap, num, ret); 200091ed5349SWolfram Sang } 200191ed5349SWolfram Sang 200291ed5349SWolfram Sang return ret; 200391ed5349SWolfram Sang } 200491ed5349SWolfram Sang EXPORT_SYMBOL(__i2c_transfer); 200591ed5349SWolfram Sang 200691ed5349SWolfram Sang /** 200791ed5349SWolfram Sang * i2c_transfer - execute a single or combined I2C message 200891ed5349SWolfram Sang * @adap: Handle to I2C bus 200991ed5349SWolfram Sang * @msgs: One or more messages to execute before STOP is issued to 201091ed5349SWolfram Sang * terminate the operation; each message begins with a START. 201191ed5349SWolfram Sang * @num: Number of messages to be executed. 201291ed5349SWolfram Sang * 201391ed5349SWolfram Sang * Returns negative errno, else the number of messages executed. 201491ed5349SWolfram Sang * 201591ed5349SWolfram Sang * Note that there is no requirement that each message be sent to 201691ed5349SWolfram Sang * the same slave address, although that is the most common model. 201791ed5349SWolfram Sang */ 201891ed5349SWolfram Sang int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 201991ed5349SWolfram Sang { 202091ed5349SWolfram Sang int ret; 202191ed5349SWolfram Sang 2022cc52612eSWolfram Sang if (!adap->algo->master_xfer) { 2023cc52612eSWolfram Sang dev_dbg(&adap->dev, "I2C level transfers not supported\n"); 2024cc52612eSWolfram Sang return -EOPNOTSUPP; 2025cc52612eSWolfram Sang } 2026cc52612eSWolfram Sang 202791ed5349SWolfram Sang /* REVISIT the fault reporting model here is weak: 202891ed5349SWolfram Sang * 202991ed5349SWolfram Sang * - When we get an error after receiving N bytes from a slave, 203091ed5349SWolfram Sang * there is no way to report "N". 203191ed5349SWolfram Sang * 203291ed5349SWolfram Sang * - When we get a NAK after transmitting N bytes to a slave, 203391ed5349SWolfram Sang * there is no way to report "N" ... or to let the master 203491ed5349SWolfram Sang * continue executing the rest of this combined message, if 203591ed5349SWolfram Sang * that's the appropriate response. 203691ed5349SWolfram Sang * 203791ed5349SWolfram Sang * - When for example "num" is two and we successfully complete 203891ed5349SWolfram Sang * the first message but get an error part way through the 203991ed5349SWolfram Sang * second, it's unclear whether that should be reported as 204091ed5349SWolfram Sang * one (discarding status on the second message) or errno 204191ed5349SWolfram Sang * (discarding status on the first one). 204291ed5349SWolfram Sang */ 204383c42212SWolfram Sang ret = __i2c_lock_bus_helper(adap); 204483c42212SWolfram Sang if (ret) 204583c42212SWolfram Sang return ret; 204691ed5349SWolfram Sang 204791ed5349SWolfram Sang ret = __i2c_transfer(adap, msgs, num); 204891ed5349SWolfram Sang i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); 204991ed5349SWolfram Sang 205091ed5349SWolfram Sang return ret; 205191ed5349SWolfram Sang } 205291ed5349SWolfram Sang EXPORT_SYMBOL(i2c_transfer); 205391ed5349SWolfram Sang 205491ed5349SWolfram Sang /** 20558a91732bSWolfram Sang * i2c_transfer_buffer_flags - issue a single I2C message transferring data 20568a91732bSWolfram Sang * to/from a buffer 205791ed5349SWolfram Sang * @client: Handle to slave device 20588a91732bSWolfram Sang * @buf: Where the data is stored 20598a91732bSWolfram Sang * @count: How many bytes to transfer, must be less than 64k since msg.len is u16 20608a91732bSWolfram Sang * @flags: The flags to be used for the message, e.g. I2C_M_RD for reads 206191ed5349SWolfram Sang * 20628a91732bSWolfram Sang * Returns negative errno, or else the number of bytes transferred. 206391ed5349SWolfram Sang */ 20648a91732bSWolfram Sang int i2c_transfer_buffer_flags(const struct i2c_client *client, char *buf, 20658a91732bSWolfram Sang int count, u16 flags) 206691ed5349SWolfram Sang { 206791ed5349SWolfram Sang int ret; 20688a91732bSWolfram Sang struct i2c_msg msg = { 20698a91732bSWolfram Sang .addr = client->addr, 20708a91732bSWolfram Sang .flags = flags | (client->flags & I2C_M_TEN), 20718a91732bSWolfram Sang .len = count, 20728a91732bSWolfram Sang .buf = buf, 20738a91732bSWolfram Sang }; 207491ed5349SWolfram Sang 20758a91732bSWolfram Sang ret = i2c_transfer(client->adapter, &msg, 1); 207691ed5349SWolfram Sang 207791ed5349SWolfram Sang /* 20788a91732bSWolfram Sang * If everything went ok (i.e. 1 msg transferred), return #bytes 20798a91732bSWolfram Sang * transferred, else error code. 208091ed5349SWolfram Sang */ 208191ed5349SWolfram Sang return (ret == 1) ? count : ret; 208291ed5349SWolfram Sang } 20838a91732bSWolfram Sang EXPORT_SYMBOL(i2c_transfer_buffer_flags); 208491ed5349SWolfram Sang 2085dde67eb1SPeter Rosin /** 2086dde67eb1SPeter Rosin * i2c_get_device_id - get manufacturer, part id and die revision of a device 2087dde67eb1SPeter Rosin * @client: The device to query 2088dde67eb1SPeter Rosin * @id: The queried information 2089dde67eb1SPeter Rosin * 2090dde67eb1SPeter Rosin * Returns negative errno on error, zero on success. 2091dde67eb1SPeter Rosin */ 2092dde67eb1SPeter Rosin int i2c_get_device_id(const struct i2c_client *client, 2093dde67eb1SPeter Rosin struct i2c_device_identity *id) 2094dde67eb1SPeter Rosin { 2095dde67eb1SPeter Rosin struct i2c_adapter *adap = client->adapter; 2096dde67eb1SPeter Rosin union i2c_smbus_data raw_id; 2097dde67eb1SPeter Rosin int ret; 2098dde67eb1SPeter Rosin 2099dde67eb1SPeter Rosin if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) 2100dde67eb1SPeter Rosin return -EOPNOTSUPP; 2101dde67eb1SPeter Rosin 2102dde67eb1SPeter Rosin raw_id.block[0] = 3; 2103dde67eb1SPeter Rosin ret = i2c_smbus_xfer(adap, I2C_ADDR_DEVICE_ID, 0, 2104dde67eb1SPeter Rosin I2C_SMBUS_READ, client->addr << 1, 2105dde67eb1SPeter Rosin I2C_SMBUS_I2C_BLOCK_DATA, &raw_id); 2106dde67eb1SPeter Rosin if (ret) 2107dde67eb1SPeter Rosin return ret; 2108dde67eb1SPeter Rosin 2109dde67eb1SPeter Rosin id->manufacturer_id = (raw_id.block[1] << 4) | (raw_id.block[2] >> 4); 2110dde67eb1SPeter Rosin id->part_id = ((raw_id.block[2] & 0xf) << 5) | (raw_id.block[3] >> 3); 2111dde67eb1SPeter Rosin id->die_revision = raw_id.block[3] & 0x7; 2112dde67eb1SPeter Rosin return 0; 2113dde67eb1SPeter Rosin } 2114dde67eb1SPeter Rosin EXPORT_SYMBOL_GPL(i2c_get_device_id); 2115dde67eb1SPeter Rosin 211691ed5349SWolfram Sang /* ---------------------------------------------------- 211791ed5349SWolfram Sang * the i2c address scanning function 211891ed5349SWolfram Sang * Will not work for 10-bit addresses! 211991ed5349SWolfram Sang * ---------------------------------------------------- 212091ed5349SWolfram Sang */ 212191ed5349SWolfram Sang 212291ed5349SWolfram Sang /* 212391ed5349SWolfram Sang * Legacy default probe function, mostly relevant for SMBus. The default 212491ed5349SWolfram Sang * probe method is a quick write, but it is known to corrupt the 24RF08 212591ed5349SWolfram Sang * EEPROMs due to a state machine bug, and could also irreversibly 212691ed5349SWolfram Sang * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, 212791ed5349SWolfram Sang * we use a short byte read instead. Also, some bus drivers don't implement 212891ed5349SWolfram Sang * quick write, so we fallback to a byte read in that case too. 212991ed5349SWolfram Sang * On x86, there is another special case for FSC hardware monitoring chips, 213091ed5349SWolfram Sang * which want regular byte reads (address 0x73.) Fortunately, these are the 213191ed5349SWolfram Sang * only known chips using this I2C address on PC hardware. 213291ed5349SWolfram Sang * Returns 1 if probe succeeded, 0 if not. 213391ed5349SWolfram Sang */ 213491ed5349SWolfram Sang static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) 213591ed5349SWolfram Sang { 213691ed5349SWolfram Sang int err; 213791ed5349SWolfram Sang union i2c_smbus_data dummy; 213891ed5349SWolfram Sang 213991ed5349SWolfram Sang #ifdef CONFIG_X86 214091ed5349SWolfram Sang if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) 214191ed5349SWolfram Sang && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) 214291ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 214391ed5349SWolfram Sang I2C_SMBUS_BYTE_DATA, &dummy); 214491ed5349SWolfram Sang else 214591ed5349SWolfram Sang #endif 214691ed5349SWolfram Sang if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) 214791ed5349SWolfram Sang && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) 214891ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, 214991ed5349SWolfram Sang I2C_SMBUS_QUICK, NULL); 215091ed5349SWolfram Sang else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) 215191ed5349SWolfram Sang err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 215291ed5349SWolfram Sang I2C_SMBUS_BYTE, &dummy); 215391ed5349SWolfram Sang else { 215491ed5349SWolfram Sang dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", 215591ed5349SWolfram Sang addr); 215691ed5349SWolfram Sang err = -EOPNOTSUPP; 215791ed5349SWolfram Sang } 215891ed5349SWolfram Sang 215991ed5349SWolfram Sang return err >= 0; 216091ed5349SWolfram Sang } 216191ed5349SWolfram Sang 216291ed5349SWolfram Sang static int i2c_detect_address(struct i2c_client *temp_client, 216391ed5349SWolfram Sang struct i2c_driver *driver) 216491ed5349SWolfram Sang { 216591ed5349SWolfram Sang struct i2c_board_info info; 216691ed5349SWolfram Sang struct i2c_adapter *adapter = temp_client->adapter; 216791ed5349SWolfram Sang int addr = temp_client->addr; 216891ed5349SWolfram Sang int err; 216991ed5349SWolfram Sang 217091ed5349SWolfram Sang /* Make sure the address is valid */ 217191ed5349SWolfram Sang err = i2c_check_7bit_addr_validity_strict(addr); 217291ed5349SWolfram Sang if (err) { 217391ed5349SWolfram Sang dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", 217491ed5349SWolfram Sang addr); 217591ed5349SWolfram Sang return err; 217691ed5349SWolfram Sang } 217791ed5349SWolfram Sang 217891ed5349SWolfram Sang /* Skip if already in use (7 bit, no need to encode flags) */ 217991ed5349SWolfram Sang if (i2c_check_addr_busy(adapter, addr)) 218091ed5349SWolfram Sang return 0; 218191ed5349SWolfram Sang 218291ed5349SWolfram Sang /* Make sure there is something at this address */ 218391ed5349SWolfram Sang if (!i2c_default_probe(adapter, addr)) 218491ed5349SWolfram Sang return 0; 218591ed5349SWolfram Sang 218691ed5349SWolfram Sang /* Finally call the custom detection function */ 218791ed5349SWolfram Sang memset(&info, 0, sizeof(struct i2c_board_info)); 218891ed5349SWolfram Sang info.addr = addr; 218991ed5349SWolfram Sang err = driver->detect(temp_client, &info); 219091ed5349SWolfram Sang if (err) { 219191ed5349SWolfram Sang /* -ENODEV is returned if the detection fails. We catch it 219291ed5349SWolfram Sang here as this isn't an error. */ 219391ed5349SWolfram Sang return err == -ENODEV ? 0 : err; 219491ed5349SWolfram Sang } 219591ed5349SWolfram Sang 219691ed5349SWolfram Sang /* Consistency check */ 219791ed5349SWolfram Sang if (info.type[0] == '\0') { 219891ed5349SWolfram Sang dev_err(&adapter->dev, 219991ed5349SWolfram Sang "%s detection function provided no name for 0x%x\n", 220091ed5349SWolfram Sang driver->driver.name, addr); 220191ed5349SWolfram Sang } else { 220291ed5349SWolfram Sang struct i2c_client *client; 220391ed5349SWolfram Sang 220491ed5349SWolfram Sang /* Detection succeeded, instantiate the device */ 220591ed5349SWolfram Sang if (adapter->class & I2C_CLASS_DEPRECATED) 220691ed5349SWolfram Sang dev_warn(&adapter->dev, 220791ed5349SWolfram Sang "This adapter will soon drop class based instantiation of devices. " 220891ed5349SWolfram Sang "Please make sure client 0x%02x gets instantiated by other means. " 2209ccf988b6SMauro Carvalho Chehab "Check 'Documentation/i2c/instantiating-devices.rst' for details.\n", 221091ed5349SWolfram Sang info.addr); 221191ed5349SWolfram Sang 221291ed5349SWolfram Sang dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", 221391ed5349SWolfram Sang info.type, info.addr); 221491ed5349SWolfram Sang client = i2c_new_device(adapter, &info); 221591ed5349SWolfram Sang if (client) 221691ed5349SWolfram Sang list_add_tail(&client->detected, &driver->clients); 221791ed5349SWolfram Sang else 221891ed5349SWolfram Sang dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", 221991ed5349SWolfram Sang info.type, info.addr); 222091ed5349SWolfram Sang } 222191ed5349SWolfram Sang return 0; 222291ed5349SWolfram Sang } 222391ed5349SWolfram Sang 222491ed5349SWolfram Sang static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) 222591ed5349SWolfram Sang { 222691ed5349SWolfram Sang const unsigned short *address_list; 222791ed5349SWolfram Sang struct i2c_client *temp_client; 222891ed5349SWolfram Sang int i, err = 0; 222991ed5349SWolfram Sang int adap_id = i2c_adapter_id(adapter); 223091ed5349SWolfram Sang 223191ed5349SWolfram Sang address_list = driver->address_list; 223291ed5349SWolfram Sang if (!driver->detect || !address_list) 223391ed5349SWolfram Sang return 0; 223491ed5349SWolfram Sang 223591ed5349SWolfram Sang /* Warn that the adapter lost class based instantiation */ 223691ed5349SWolfram Sang if (adapter->class == I2C_CLASS_DEPRECATED) { 223791ed5349SWolfram Sang dev_dbg(&adapter->dev, 223891ed5349SWolfram Sang "This adapter dropped support for I2C classes and won't auto-detect %s devices anymore. " 2239ccf988b6SMauro Carvalho Chehab "If you need it, check 'Documentation/i2c/instantiating-devices.rst' for alternatives.\n", 224091ed5349SWolfram Sang driver->driver.name); 224191ed5349SWolfram Sang return 0; 224291ed5349SWolfram Sang } 224391ed5349SWolfram Sang 224491ed5349SWolfram Sang /* Stop here if the classes do not match */ 224591ed5349SWolfram Sang if (!(adapter->class & driver->class)) 224691ed5349SWolfram Sang return 0; 224791ed5349SWolfram Sang 224891ed5349SWolfram Sang /* Set up a temporary client to help detect callback */ 224991ed5349SWolfram Sang temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); 225091ed5349SWolfram Sang if (!temp_client) 225191ed5349SWolfram Sang return -ENOMEM; 225291ed5349SWolfram Sang temp_client->adapter = adapter; 225391ed5349SWolfram Sang 225491ed5349SWolfram Sang for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { 225591ed5349SWolfram Sang dev_dbg(&adapter->dev, 225691ed5349SWolfram Sang "found normal entry for adapter %d, addr 0x%02x\n", 225791ed5349SWolfram Sang adap_id, address_list[i]); 225891ed5349SWolfram Sang temp_client->addr = address_list[i]; 225991ed5349SWolfram Sang err = i2c_detect_address(temp_client, driver); 226091ed5349SWolfram Sang if (unlikely(err)) 226191ed5349SWolfram Sang break; 226291ed5349SWolfram Sang } 226391ed5349SWolfram Sang 226491ed5349SWolfram Sang kfree(temp_client); 226591ed5349SWolfram Sang return err; 226691ed5349SWolfram Sang } 226791ed5349SWolfram Sang 226891ed5349SWolfram Sang int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) 226991ed5349SWolfram Sang { 227091ed5349SWolfram Sang return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, 227191ed5349SWolfram Sang I2C_SMBUS_QUICK, NULL) >= 0; 227291ed5349SWolfram Sang } 227391ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); 227491ed5349SWolfram Sang 227591ed5349SWolfram Sang struct i2c_client * 227691ed5349SWolfram Sang i2c_new_probed_device(struct i2c_adapter *adap, 227791ed5349SWolfram Sang struct i2c_board_info *info, 227891ed5349SWolfram Sang unsigned short const *addr_list, 2279edd7a563SWolfram Sang int (*probe)(struct i2c_adapter *adap, unsigned short addr)) 228091ed5349SWolfram Sang { 228191ed5349SWolfram Sang int i; 228291ed5349SWolfram Sang 228391ed5349SWolfram Sang if (!probe) 228491ed5349SWolfram Sang probe = i2c_default_probe; 228591ed5349SWolfram Sang 228691ed5349SWolfram Sang for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { 228791ed5349SWolfram Sang /* Check address validity */ 228891ed5349SWolfram Sang if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { 228991ed5349SWolfram Sang dev_warn(&adap->dev, "Invalid 7-bit address 0x%02x\n", 229091ed5349SWolfram Sang addr_list[i]); 229191ed5349SWolfram Sang continue; 229291ed5349SWolfram Sang } 229391ed5349SWolfram Sang 229491ed5349SWolfram Sang /* Check address availability (7 bit, no need to encode flags) */ 229591ed5349SWolfram Sang if (i2c_check_addr_busy(adap, addr_list[i])) { 229691ed5349SWolfram Sang dev_dbg(&adap->dev, 229791ed5349SWolfram Sang "Address 0x%02x already in use, not probing\n", 229891ed5349SWolfram Sang addr_list[i]); 229991ed5349SWolfram Sang continue; 230091ed5349SWolfram Sang } 230191ed5349SWolfram Sang 230291ed5349SWolfram Sang /* Test address responsiveness */ 230391ed5349SWolfram Sang if (probe(adap, addr_list[i])) 230491ed5349SWolfram Sang break; 230591ed5349SWolfram Sang } 230691ed5349SWolfram Sang 230791ed5349SWolfram Sang if (addr_list[i] == I2C_CLIENT_END) { 230891ed5349SWolfram Sang dev_dbg(&adap->dev, "Probing failed, no device found\n"); 230991ed5349SWolfram Sang return NULL; 231091ed5349SWolfram Sang } 231191ed5349SWolfram Sang 231291ed5349SWolfram Sang info->addr = addr_list[i]; 231391ed5349SWolfram Sang return i2c_new_device(adap, info); 231491ed5349SWolfram Sang } 231591ed5349SWolfram Sang EXPORT_SYMBOL_GPL(i2c_new_probed_device); 231691ed5349SWolfram Sang 231791ed5349SWolfram Sang struct i2c_adapter *i2c_get_adapter(int nr) 231891ed5349SWolfram Sang { 231991ed5349SWolfram Sang struct i2c_adapter *adapter; 232091ed5349SWolfram Sang 232191ed5349SWolfram Sang mutex_lock(&core_lock); 232291ed5349SWolfram Sang adapter = idr_find(&i2c_adapter_idr, nr); 232391ed5349SWolfram Sang if (!adapter) 232491ed5349SWolfram Sang goto exit; 232591ed5349SWolfram Sang 232691ed5349SWolfram Sang if (try_module_get(adapter->owner)) 232791ed5349SWolfram Sang get_device(&adapter->dev); 232891ed5349SWolfram Sang else 232991ed5349SWolfram Sang adapter = NULL; 233091ed5349SWolfram Sang 233191ed5349SWolfram Sang exit: 233291ed5349SWolfram Sang mutex_unlock(&core_lock); 233391ed5349SWolfram Sang return adapter; 233491ed5349SWolfram Sang } 233591ed5349SWolfram Sang EXPORT_SYMBOL(i2c_get_adapter); 233691ed5349SWolfram Sang 233791ed5349SWolfram Sang void i2c_put_adapter(struct i2c_adapter *adap) 233891ed5349SWolfram Sang { 233991ed5349SWolfram Sang if (!adap) 234091ed5349SWolfram Sang return; 234191ed5349SWolfram Sang 234291ed5349SWolfram Sang put_device(&adap->dev); 234391ed5349SWolfram Sang module_put(adap->owner); 234491ed5349SWolfram Sang } 234591ed5349SWolfram Sang EXPORT_SYMBOL(i2c_put_adapter); 234691ed5349SWolfram Sang 2347e94bc5d1SWolfram Sang /** 2348e94bc5d1SWolfram Sang * i2c_get_dma_safe_msg_buf() - get a DMA safe buffer for the given i2c_msg 2349e94bc5d1SWolfram Sang * @msg: the message to be checked 2350bf263c35SWolfram Sang * @threshold: the minimum number of bytes for which using DMA makes sense. 2351bf263c35SWolfram Sang * Should at least be 1. 2352e94bc5d1SWolfram Sang * 2353e94bc5d1SWolfram Sang * Return: NULL if a DMA safe buffer was not obtained. Use msg->buf with PIO. 2354e94bc5d1SWolfram Sang * Or a valid pointer to be used with DMA. After use, release it by 235534d1b82cSStephen Boyd * calling i2c_put_dma_safe_msg_buf(). 2356e94bc5d1SWolfram Sang * 2357e94bc5d1SWolfram Sang * This function must only be called from process context! 2358e94bc5d1SWolfram Sang */ 2359e94bc5d1SWolfram Sang u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold) 2360e94bc5d1SWolfram Sang { 2361bf263c35SWolfram Sang /* also skip 0-length msgs for bogus thresholds of 0 */ 2362bf263c35SWolfram Sang if (!threshold) 2363bf263c35SWolfram Sang pr_debug("DMA buffer for addr=0x%02x with length 0 is bogus\n", 2364bf263c35SWolfram Sang msg->addr); 2365bf263c35SWolfram Sang if (msg->len < threshold || msg->len == 0) 2366e94bc5d1SWolfram Sang return NULL; 2367e94bc5d1SWolfram Sang 2368e94bc5d1SWolfram Sang if (msg->flags & I2C_M_DMA_SAFE) 2369e94bc5d1SWolfram Sang return msg->buf; 2370e94bc5d1SWolfram Sang 2371e94bc5d1SWolfram Sang pr_debug("using bounce buffer for addr=0x%02x, len=%d\n", 2372e94bc5d1SWolfram Sang msg->addr, msg->len); 2373e94bc5d1SWolfram Sang 2374e94bc5d1SWolfram Sang if (msg->flags & I2C_M_RD) 2375e94bc5d1SWolfram Sang return kzalloc(msg->len, GFP_KERNEL); 2376e94bc5d1SWolfram Sang else 2377e94bc5d1SWolfram Sang return kmemdup(msg->buf, msg->len, GFP_KERNEL); 2378e94bc5d1SWolfram Sang } 2379e94bc5d1SWolfram Sang EXPORT_SYMBOL_GPL(i2c_get_dma_safe_msg_buf); 2380e94bc5d1SWolfram Sang 2381e94bc5d1SWolfram Sang /** 238282fe39a6SWolfram Sang * i2c_put_dma_safe_msg_buf - release DMA safe buffer and sync with i2c_msg 2383e94bc5d1SWolfram Sang * @buf: the buffer obtained from i2c_get_dma_safe_msg_buf(). May be NULL. 238482fe39a6SWolfram Sang * @msg: the message which the buffer corresponds to 238582fe39a6SWolfram Sang * @xferred: bool saying if the message was transferred 2386e94bc5d1SWolfram Sang */ 238782fe39a6SWolfram Sang void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred) 2388e94bc5d1SWolfram Sang { 2389e94bc5d1SWolfram Sang if (!buf || buf == msg->buf) 2390e94bc5d1SWolfram Sang return; 2391e94bc5d1SWolfram Sang 239282fe39a6SWolfram Sang if (xferred && msg->flags & I2C_M_RD) 2393e94bc5d1SWolfram Sang memcpy(msg->buf, buf, msg->len); 2394e94bc5d1SWolfram Sang 2395e94bc5d1SWolfram Sang kfree(buf); 2396e94bc5d1SWolfram Sang } 239782fe39a6SWolfram Sang EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf); 2398e94bc5d1SWolfram Sang 239991ed5349SWolfram Sang MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); 240091ed5349SWolfram Sang MODULE_DESCRIPTION("I2C-Bus main module"); 240191ed5349SWolfram Sang MODULE_LICENSE("GPL"); 2402