From b8f5fe3bc5b9318d95770a09a480c31aced20cd2 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Thu, 16 May 2019 23:13:09 +0200 Subject: [PATCH] i2c: core: add device-managed version of i2c_new_dummy i2c_new_dummy is typically called from the probe function of the driver for the primary i2c client. It requires calls to i2c_unregister_device in the error path of the probe function and in the remove function. This can be simplified by introducing a device-managed version. Note the changed error case return value type: i2c_new_dummy returns NULL whilst devm_i2c_new_dummy_device returns an ERR_PTR. Signed-off-by: Heiner Kallweit [wsa: rename new functions and fix minor kdoc issues] Signed-off-by: Wolfram Sang Reviewed-by: Peter Rosin Reviewed-by: Kieran Bingham Reviewed-by: Bartosz Golaszewski Signed-off-by: Wolfram Sang --- Documentation/driver-model/devres.txt | 3 ++ drivers/i2c/i2c-core-base.c | 44 +++++++++++++++++++++++++++ include/linux/i2c.h | 3 ++ 3 files changed, 50 insertions(+) diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt index 99994a461359..69c7fa7f616c 100644 --- a/Documentation/driver-model/devres.txt +++ b/Documentation/driver-model/devres.txt @@ -271,6 +271,9 @@ GPIO devm_gpio_request_one() devm_gpio_free() +I2C + devm_i2c_new_dummy_device() + IIO devm_iio_device_alloc() devm_iio_device_free() diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 9c38dde73366..d389d4fb0623 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -929,6 +929,50 @@ struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) } EXPORT_SYMBOL_GPL(i2c_new_dummy); +struct i2c_dummy_devres { + struct i2c_client *client; +}; + +static void devm_i2c_release_dummy(struct device *dev, void *res) +{ + struct i2c_dummy_devres *this = res; + + i2c_unregister_device(this->client); +} + +/** + * devm_i2c_new_dummy_device - return a new i2c device bound to a dummy driver + * @dev: device the managed resource is bound to + * @adapter: the adapter managing the device + * @address: seven bit address to be used + * Context: can sleep + * + * This is the device-managed version of @i2c_new_dummy_device. It returns the + * new i2c client or an ERR_PTR in case of an error. + */ +struct i2c_client *devm_i2c_new_dummy_device(struct device *dev, + struct i2c_adapter *adapter, + u16 address) +{ + struct i2c_dummy_devres *dr; + struct i2c_client *client; + + dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); + if (!dr) + return ERR_PTR(-ENOMEM); + + client = i2c_new_dummy_device(adapter, address); + if (IS_ERR(client)) { + devres_free(dr); + } else { + dr->client = client; + devres_add(dev, dr); + } + + return client; +} +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy_device); + /** * i2c_new_secondary_device - Helper to get the instantiated secondary address * and create the associated device diff --git a/include/linux/i2c.h b/include/linux/i2c.h index be27062f8ed1..6c4db54714f6 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -469,6 +469,9 @@ extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); extern struct i2c_client * i2c_new_dummy(struct i2c_adapter *adap, u16 address); +extern struct i2c_client * +devm_i2c_new_dummy_device(struct device *dev, struct i2c_adapter *adap, u16 address); + extern struct i2c_client * i2c_new_secondary_device(struct i2c_client *client, const char *name, -- 2.30.2