diff options
| -rw-r--r-- | drivers/i2c/i2c-core.c | 49 | ||||
| -rw-r--r-- | include/linux/i2c.h | 7 |
2 files changed, 56 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index f7faa991a44c..00c4cef716f7 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -421,6 +421,55 @@ static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value, static struct notifier_block i2c_acpi_notifier = { .notifier_call = i2c_acpi_notify, }; + +/** + * i2c_acpi_new_device - Create i2c-client for the Nth I2cSerialBus resource + * @dev: Device owning the ACPI resources to get the client from + * @index: Index of ACPI resource to get + * @info: describes the I2C device; note this is modified (addr gets set) + * Context: can sleep + * + * By default the i2c subsys creates an i2c-client for the first I2cSerialBus + * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus + * resources, in that case this function can be used to create an i2c-client + * for other I2cSerialBus resources in the Current Resource Settings table. + * + * Also see i2c_new_device, which this function calls to create the i2c-client. + * + * Returns a pointer to the new i2c-client, or NULL if the adapter is not found. + */ +struct i2c_client *i2c_acpi_new_device(struct device *dev, int index, + struct i2c_board_info *info) +{ + struct i2c_acpi_lookup lookup; + struct i2c_adapter *adapter; + struct acpi_device *adev; + LIST_HEAD(resource_list); + int ret; + + adev = ACPI_COMPANION(dev); + if (!adev) + return NULL; + + memset(&lookup, 0, sizeof(lookup)); + lookup.info = info; + lookup.device_handle = acpi_device_handle(adev); + lookup.index = index; + + ret = acpi_dev_get_resources(adev, &resource_list, + i2c_acpi_fill_info, &lookup); + acpi_dev_free_resource_list(&resource_list); + + if (ret < 0 || !info->addr) + return NULL; + + adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle); + if (!adapter) + return NULL; + + return i2c_new_device(adapter, info); +} +EXPORT_SYMBOL_GPL(i2c_acpi_new_device); #else /* CONFIG_ACPI */ static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { } extern struct notifier_block i2c_acpi_notifier; diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 6b183521c616..53fa50fc63fb 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -824,11 +824,18 @@ static inline const struct of_device_id #if IS_ENABLED(CONFIG_ACPI) u32 i2c_acpi_find_bus_speed(struct device *dev); +struct i2c_client *i2c_acpi_new_device(struct device *dev, int index, + struct i2c_board_info *info); #else static inline u32 i2c_acpi_find_bus_speed(struct device *dev) { return 0; } +static inline struct i2c_client *i2c_acpi_new_device(struct device *dev, + int index, struct i2c_board_info *info) +{ + return NULL; +} #endif /* CONFIG_ACPI */ #endif /* _LINUX_I2C_H */ |