diff options
Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r-- | drivers/i2c/i2c-core.c | 165 |
1 files changed, 107 insertions, 58 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 74e5aeaf84f9..da3a02ef4a31 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -27,6 +27,8 @@ I2C slave support (c) 2014 by Wolfram Sang <wsa@sang-engineering.com> */ +#define pr_fmt(fmt) "i2c-core: " fmt + #include <dt-bindings/i2c/i2c.h> #include <asm/uaccess.h> #include <linux/acpi.h> @@ -493,7 +495,8 @@ acpi_i2c_space_handler(u32 function, acpi_physical_address command, break; default: - pr_info("protocol(0x%02x) is not supported.\n", accessor_type); + dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n", + accessor_type, client->addr); ret = AE_BAD_PARAMETER; goto err; } @@ -759,6 +762,47 @@ int i2c_recover_bus(struct i2c_adapter *adap) } EXPORT_SYMBOL_GPL(i2c_recover_bus); +static void i2c_init_recovery(struct i2c_adapter *adap) +{ + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; + char *err_str; + + if (!bri) + return; + + if (!bri->recover_bus) { + err_str = "no recover_bus() found"; + goto err; + } + + /* Generic GPIO recovery */ + if (bri->recover_bus == i2c_generic_gpio_recovery) { + if (!gpio_is_valid(bri->scl_gpio)) { + err_str = "invalid SCL gpio"; + goto err; + } + + if (gpio_is_valid(bri->sda_gpio)) + bri->get_sda = get_sda_gpio_value; + else + bri->get_sda = NULL; + + bri->get_scl = get_scl_gpio_value; + bri->set_scl = set_scl_gpio_value; + } else if (bri->recover_bus == i2c_generic_scl_recovery) { + /* Generic SCL recovery */ + if (!bri->set_scl || !bri->get_scl) { + err_str = "no {get|set}_scl() found"; + goto err; + } + } + + return; + err: + dev_err(&adap->dev, "Not using recovery: %s\n", err_str); + adap->bus_recovery_info = NULL; +} + static int i2c_device_probe(struct device *dev) { struct i2c_client *client = i2c_verify_client(dev); @@ -1240,6 +1284,47 @@ struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) } EXPORT_SYMBOL_GPL(i2c_new_dummy); +/** + * i2c_new_secondary_device - Helper to get the instantiated secondary address + * and create the associated device + * @client: Handle to the primary client + * @name: Handle to specify which secondary address to get + * @default_addr: Used as a fallback if no secondary address was specified + * Context: can sleep + * + * I2C clients can be composed of multiple I2C slaves bound together in a single + * component. The I2C client driver then binds to the master I2C slave and needs + * to create I2C dummy clients to communicate with all the other slaves. + * + * This function creates and returns an I2C dummy client whose I2C address is + * retrieved from the platform firmware based on the given slave name. If no + * address is specified by the firmware default_addr is used. + * + * On DT-based platforms the address is retrieved from the "reg" property entry + * cell whose "reg-names" value matches the slave name. + * + * This returns the new i2c client, which should be saved for later use with + * i2c_unregister_device(); or NULL to indicate an error. + */ +struct i2c_client *i2c_new_secondary_device(struct i2c_client *client, + const char *name, + u16 default_addr) +{ + struct device_node *np = client->dev.of_node; + u32 addr = default_addr; + int i; + + if (np) { + i = of_property_match_string(np, "reg-names", name); + if (i >= 0) + of_property_read_u32_index(np, "reg", i, &addr); + } + + dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); + return i2c_new_dummy(client->adapter, addr); +} +EXPORT_SYMBOL_GPL(i2c_new_secondary_device); + /* ------------------------------------------------------------------------- */ /* I2C bus adapters -- one roots each I2C or SMBUS segment */ @@ -1608,7 +1693,7 @@ static int __process_new_adapter(struct device_driver *d, void *data) static int i2c_register_adapter(struct i2c_adapter *adap) { - int res = 0; + int res = -EINVAL; /* Can't register until after driver model init */ if (WARN_ON(!is_registered)) { @@ -1617,15 +1702,12 @@ static int i2c_register_adapter(struct i2c_adapter *adap) } /* Sanity checks */ - if (unlikely(adap->name[0] == '\0')) { - pr_err("i2c-core: Attempt to register an adapter with " - "no name!\n"); - return -EINVAL; - } - if (unlikely(!adap->algo)) { - pr_err("i2c-core: Attempt to register adapter '%s' with " - "no algo!\n", adap->name); - return -EINVAL; + if (WARN(!adap->name[0], "i2c adapter has no name")) + goto out_list; + + if (!adap->algo) { + pr_err("adapter '%s': no algo supplied!\n", adap->name); + goto out_list; } if (!adap->lock_bus) { @@ -1647,8 +1729,10 @@ static int i2c_register_adapter(struct i2c_adapter *adap) adap->dev.bus = &i2c_bus_type; adap->dev.type = &i2c_adapter_type; res = device_register(&adap->dev); - if (res) + if (res) { + pr_err("adapter '%s': can't register device (%d)\n", adap->name, res); goto out_list; + } dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); @@ -1664,41 +1748,8 @@ static int i2c_register_adapter(struct i2c_adapter *adap) "Failed to create compatibility class link\n"); #endif - /* bus recovery specific initialization */ - if (adap->bus_recovery_info) { - struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; - - if (!bri->recover_bus) { - dev_err(&adap->dev, "No recover_bus() found, not using recovery\n"); - adap->bus_recovery_info = NULL; - goto exit_recovery; - } - - /* Generic GPIO recovery */ - if (bri->recover_bus == i2c_generic_gpio_recovery) { - if (!gpio_is_valid(bri->scl_gpio)) { - dev_err(&adap->dev, "Invalid SCL gpio, not using recovery\n"); - adap->bus_recovery_info = NULL; - goto exit_recovery; - } + i2c_init_recovery(adap); - if (gpio_is_valid(bri->sda_gpio)) - bri->get_sda = get_sda_gpio_value; - else - bri->get_sda = NULL; - - bri->get_scl = get_scl_gpio_value; - bri->set_scl = set_scl_gpio_value; - } else if (bri->recover_bus == i2c_generic_scl_recovery) { - /* Generic SCL recovery */ - if (!bri->set_scl || !bri->get_scl) { - dev_err(&adap->dev, "No {get|set}_scl() found, not using recovery\n"); - adap->bus_recovery_info = NULL; - } - } - } - -exit_recovery: /* create pre-declared device nodes */ of_i2c_register_devices(adap); acpi_i2c_register_devices(adap); @@ -1730,13 +1781,12 @@ out_list: */ static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) { - int id; + int id; mutex_lock(&core_lock); - id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, - GFP_KERNEL); + id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); mutex_unlock(&core_lock); - if (id < 0) + if (WARN(id < 0, "couldn't get idr")) return id == -ENOSPC ? -EBUSY : id; return i2c_register_adapter(adap); @@ -1773,7 +1823,7 @@ int i2c_add_adapter(struct i2c_adapter *adapter) id = idr_alloc(&i2c_adapter_idr, adapter, __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); mutex_unlock(&core_lock); - if (id < 0) + if (WARN(id < 0, "couldn't get idr")) return id; adapter->nr = id; @@ -1871,8 +1921,7 @@ void i2c_del_adapter(struct i2c_adapter *adap) found = idr_find(&i2c_adapter_idr, adap->nr); mutex_unlock(&core_lock); if (found != adap) { - pr_debug("i2c-core: attempting to delete unregistered " - "adapter [%s]\n", adap->name); + pr_debug("attempting to delete unregistered adapter [%s]\n", adap->name); return; } @@ -2032,7 +2081,7 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver) if (res) return res; - pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); + pr_debug("driver [%s] registered\n", driver->driver.name); INIT_LIST_HEAD(&driver->clients); /* Walk the adapters that are already present */ @@ -2059,7 +2108,7 @@ void i2c_del_driver(struct i2c_driver *driver) i2c_for_each_dev(driver, __process_removed_driver); driver_unregister(&driver->driver); - pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); + pr_debug("driver [%s] unregistered\n", driver->driver.name); } EXPORT_SYMBOL(i2c_del_driver); @@ -2150,8 +2199,8 @@ static int of_i2c_notify(struct notifier_block *nb, unsigned long action, put_device(&adap->dev); if (IS_ERR(client)) { - pr_err("%s: failed to create for '%s'\n", - __func__, rd->dn->full_name); + dev_err(&adap->dev, "failed to create client for '%s'\n", + rd->dn->full_name); return notifier_from_errno(PTR_ERR(client)); } break; @@ -2772,7 +2821,7 @@ static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) cpec = i2c_smbus_msg_pec(cpec, msg); if (rpec != cpec) { - pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", + pr_debug("Bad PEC 0x%02x vs. 0x%02x\n", rpec, cpec); return -EBADMSG; } |