diff options
Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r-- | drivers/i2c/i2c-core.c | 229 |
1 files changed, 137 insertions, 92 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 3202a86f420e..7c469a62c3c1 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -40,12 +40,11 @@ #include "i2c-core.h" -/* core_lock protects i2c_adapter_idr, userspace_devices, and guarantees +/* core_lock protects i2c_adapter_idr, and guarantees that device detection, deletion of detected devices, and attach_adapter and detach_adapter calls are serialized */ static DEFINE_MUTEX(core_lock); static DEFINE_IDR(i2c_adapter_idr); -static LIST_HEAD(userspace_devices); static struct device_type i2c_client_type; static int i2c_check_addr(struct i2c_adapter *adapter, int addr); @@ -117,8 +116,10 @@ static int i2c_device_probe(struct device *dev) dev_dbg(dev, "probe\n"); status = driver->probe(client, i2c_match_id(driver->id_table, client)); - if (status) + if (status) { client->driver = NULL; + i2c_set_clientdata(client, NULL); + } return status; } @@ -139,8 +140,10 @@ static int i2c_device_remove(struct device *dev) dev->driver = NULL; status = 0; } - if (status == 0) + if (status == 0) { client->driver = NULL; + i2c_set_clientdata(client, NULL); + } return status; } @@ -156,106 +159,130 @@ static void i2c_device_shutdown(struct device *dev) driver->shutdown(client); } -#ifdef CONFIG_SUSPEND -static int i2c_device_pm_suspend(struct device *dev) +#ifdef CONFIG_PM_SLEEP +static int i2c_legacy_suspend(struct device *dev, pm_message_t mesg) { - const struct dev_pm_ops *pm; + struct i2c_client *client = i2c_verify_client(dev); + struct i2c_driver *driver; - if (!dev->driver) + if (!client || !dev->driver) return 0; - pm = dev->driver->pm; - if (!pm || !pm->suspend) + driver = to_i2c_driver(dev->driver); + if (!driver->suspend) return 0; - return pm->suspend(dev); + return driver->suspend(client, mesg); } -static int i2c_device_pm_resume(struct device *dev) +static int i2c_legacy_resume(struct device *dev) { - const struct dev_pm_ops *pm; + struct i2c_client *client = i2c_verify_client(dev); + struct i2c_driver *driver; - if (!dev->driver) + if (!client || !dev->driver) return 0; - pm = dev->driver->pm; - if (!pm || !pm->resume) + driver = to_i2c_driver(dev->driver); + if (!driver->resume) return 0; - return pm->resume(dev); + return driver->resume(client); } -#else -#define i2c_device_pm_suspend NULL -#define i2c_device_pm_resume NULL -#endif -#ifdef CONFIG_PM_RUNTIME -static int i2c_device_runtime_suspend(struct device *dev) +static int i2c_device_pm_suspend(struct device *dev) { - const struct dev_pm_ops *pm; + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (!dev->driver) + if (pm_runtime_suspended(dev)) return 0; - pm = dev->driver->pm; - if (!pm || !pm->runtime_suspend) - return 0; - return pm->runtime_suspend(dev); -} -static int i2c_device_runtime_resume(struct device *dev) -{ - const struct dev_pm_ops *pm; + if (pm) + return pm->suspend ? pm->suspend(dev) : 0; - if (!dev->driver) - return 0; - pm = dev->driver->pm; - if (!pm || !pm->runtime_resume) - return 0; - return pm->runtime_resume(dev); + return i2c_legacy_suspend(dev, PMSG_SUSPEND); } -static int i2c_device_runtime_idle(struct device *dev) +static int i2c_device_pm_resume(struct device *dev) { - const struct dev_pm_ops *pm = NULL; + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; int ret; - if (dev->driver) - pm = dev->driver->pm; - if (pm && pm->runtime_idle) { - ret = pm->runtime_idle(dev); - if (ret) - return ret; + if (pm) + ret = pm->resume ? pm->resume(dev) : 0; + else + ret = i2c_legacy_resume(dev); + + if (!ret) { + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); } - return pm_runtime_suspend(dev); + return ret; } -#else -#define i2c_device_runtime_suspend NULL -#define i2c_device_runtime_resume NULL -#define i2c_device_runtime_idle NULL -#endif -static int i2c_device_suspend(struct device *dev, pm_message_t mesg) +static int i2c_device_pm_freeze(struct device *dev) { - struct i2c_client *client = i2c_verify_client(dev); - struct i2c_driver *driver; + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (!client || !dev->driver) + if (pm_runtime_suspended(dev)) return 0; - driver = to_i2c_driver(dev->driver); - if (!driver->suspend) - return 0; - return driver->suspend(client, mesg); + + if (pm) + return pm->freeze ? pm->freeze(dev) : 0; + + return i2c_legacy_suspend(dev, PMSG_FREEZE); } -static int i2c_device_resume(struct device *dev) +static int i2c_device_pm_thaw(struct device *dev) { - struct i2c_client *client = i2c_verify_client(dev); - struct i2c_driver *driver; + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - if (!client || !dev->driver) + if (pm_runtime_suspended(dev)) return 0; - driver = to_i2c_driver(dev->driver); - if (!driver->resume) + + if (pm) + return pm->thaw ? pm->thaw(dev) : 0; + + return i2c_legacy_resume(dev); +} + +static int i2c_device_pm_poweroff(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + if (pm_runtime_suspended(dev)) return 0; - return driver->resume(client); + + if (pm) + return pm->poweroff ? pm->poweroff(dev) : 0; + + return i2c_legacy_suspend(dev, PMSG_HIBERNATE); +} + +static int i2c_device_pm_restore(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + int ret; + + if (pm) + ret = pm->restore ? pm->restore(dev) : 0; + else + ret = i2c_legacy_resume(dev); + + if (!ret) { + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + } + + return ret; } +#else /* !CONFIG_PM_SLEEP */ +#define i2c_device_pm_suspend NULL +#define i2c_device_pm_resume NULL +#define i2c_device_pm_freeze NULL +#define i2c_device_pm_thaw NULL +#define i2c_device_pm_poweroff NULL +#define i2c_device_pm_restore NULL +#endif /* !CONFIG_PM_SLEEP */ static void i2c_client_dev_release(struct device *dev) { @@ -298,9 +325,15 @@ static const struct attribute_group *i2c_dev_attr_groups[] = { static const struct dev_pm_ops i2c_device_pm_ops = { .suspend = i2c_device_pm_suspend, .resume = i2c_device_pm_resume, - .runtime_suspend = i2c_device_runtime_suspend, - .runtime_resume = i2c_device_runtime_resume, - .runtime_idle = i2c_device_runtime_idle, + .freeze = i2c_device_pm_freeze, + .thaw = i2c_device_pm_thaw, + .poweroff = i2c_device_pm_poweroff, + .restore = i2c_device_pm_restore, + SET_RUNTIME_PM_OPS( + pm_generic_runtime_suspend, + pm_generic_runtime_resume, + pm_generic_runtime_idle + ) }; struct bus_type i2c_bus_type = { @@ -309,8 +342,6 @@ struct bus_type i2c_bus_type = { .probe = i2c_device_probe, .remove = i2c_device_remove, .shutdown = i2c_device_shutdown, - .suspend = i2c_device_suspend, - .resume = i2c_device_resume, .pm = &i2c_device_pm_ops, }; EXPORT_SYMBOL_GPL(i2c_bus_type); @@ -538,9 +569,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, return -EEXIST; /* Keep track of the added device */ - mutex_lock(&core_lock); - list_add_tail(&client->detected, &userspace_devices); - mutex_unlock(&core_lock); + i2c_lock_adapter(adap); + list_add_tail(&client->detected, &adap->userspace_clients); + i2c_unlock_adapter(adap); dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", info.type, info.addr); @@ -579,9 +610,10 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, /* Make sure the device was added through sysfs */ res = -ENOENT; - mutex_lock(&core_lock); - list_for_each_entry_safe(client, next, &userspace_devices, detected) { - if (client->addr == addr && client->adapter == adap) { + i2c_lock_adapter(adap); + list_for_each_entry_safe(client, next, &adap->userspace_clients, + detected) { + if (client->addr == addr) { dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", "delete_device", client->name, client->addr); @@ -591,7 +623,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, break; } } - mutex_unlock(&core_lock); + i2c_unlock_adapter(adap); if (res < 0) dev_err(dev, "%s: Can't find device in list\n", @@ -673,6 +705,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap) } rt_mutex_init(&adap->bus_lock); + INIT_LIST_HEAD(&adap->userspace_clients); /* Set default timeout to 1 second if not already set */ if (adap->timeout == 0) @@ -875,14 +908,15 @@ int i2c_del_adapter(struct i2c_adapter *adap) return res; /* Remove devices instantiated from sysfs */ - list_for_each_entry_safe(client, next, &userspace_devices, detected) { - if (client->adapter == adap) { - dev_dbg(&adap->dev, "Removing %s at 0x%x\n", - client->name, client->addr); - list_del(&client->detected); - i2c_unregister_device(client); - } + i2c_lock_adapter(adap); + list_for_each_entry_safe(client, next, &adap->userspace_clients, + detected) { + dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, + client->addr); + list_del(&client->detected); + i2c_unregister_device(client); } + i2c_unlock_adapter(adap); /* Detach any active clients. This can't fail, thus we do not checking the returned value. */ @@ -1260,12 +1294,23 @@ static int i2c_detect_address(struct i2c_client *temp_client, return 0; /* Make sure there is something at this address */ - if (i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL) < 0) - return 0; + if (addr == 0x73 && (adapter->class & I2C_CLASS_HWMON)) { + /* Special probe for FSC hwmon chips */ + union i2c_smbus_data dummy; - /* Prevent 24RF08 corruption */ - if ((addr & ~0x0f) == 0x50) - i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL); + if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_READ, 0, + I2C_SMBUS_BYTE_DATA, &dummy) < 0) + return 0; + } else { + if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0, + I2C_SMBUS_QUICK, NULL) < 0) + return 0; + + /* Prevent 24RF08 corruption */ + if ((addr & ~0x0f) == 0x50) + i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0, + I2C_SMBUS_QUICK, NULL); + } /* Finally call the custom detection function */ memset(&info, 0, sizeof(struct i2c_board_info)); |