From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiner Kallweit Subject: [PATCH resubmit 1/2] i2c: core: add device-managed version of i2c_new_dummy Date: Tue, 5 Dec 2017 20:44:54 +0100 Message-ID: <19d37e48-0b64-b33c-993a-a1cae39efb54@gmail.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wm0-f68.google.com ([74.125.82.68]:35683 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750812AbdLETpN (ORCPT ); Tue, 5 Dec 2017 14:45:13 -0500 In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Bartosz Golaszewski , Wolfram Sang , Peter Rosin Cc: "linux-i2c@vger.kernel.org" , Linux Kernel Mailing List 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_new_i2c_dummy returns an ERR_PTR. Signed-off-by: Heiner Kallweit Reviewed-by: Peter Rosin --- Documentation/driver-model/devres.txt | 3 +++ drivers/i2c/i2c-core-base.c | 39 +++++++++++++++++++++++++++++++++++ include/linux/i2c.h | 3 +++ 3 files changed, 45 insertions(+) diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt index c180045eb..6e2bccf85 100644 --- a/Documentation/driver-model/devres.txt +++ b/Documentation/driver-model/devres.txt @@ -259,6 +259,9 @@ GPIO devm_gpio_request_one() devm_gpio_free() +I2C + devm_i2c_new_dummy + 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 bf52cca87..c1db67f9a 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -820,6 +820,45 @@ struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) } EXPORT_SYMBOL_GPL(i2c_new_dummy); +static void devm_i2c_release_dummy(struct device *dev, void *res) +{ + i2c_unregister_device(*(struct i2c_client **)res); +} + +/** + * devm_i2c_new_dummy - 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. + * Note the changed return value type: It returns the new i2c client + * or an ERR_PTR in case of an error. + */ +struct i2c_client *devm_i2c_new_dummy(struct device *dev, + struct i2c_adapter *adapter, + u16 address) +{ + struct i2c_client *ret, **dr; + + dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); + if (!dr) + return ERR_PTR(-ENOMEM); + + ret = i2c_new_dummy(adapter, address); + if (!ret) { + devres_free(dr); + return ERR_PTR(-EBUSY); + } + + *dr = ret; + devres_add(dev, dr); + + return ret; +} +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy); + /** * 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 a556db976..c27eac1e1 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -383,6 +383,9 @@ 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(struct device *dev, struct i2c_adapter *adap, u16 address); + extern struct i2c_client * i2c_new_secondary_device(struct i2c_client *client, const char *name, -- 2.15.1