From efc2c0133f198bc65593a67015af358919b0c48f Mon Sep 17 00:00:00 2001 From: Laxman Dewangan Date: Wed, 6 Apr 2016 16:01:07 +0530 Subject: [PATCH] iio: core: Add devm_ APIs for iio_channel_{get,release}_all Some of kernel driver uses the IIO framework to get the sensor value via ADC or IIO HW driver. The client driver get iio channel by iio_channel_get_all() and release it by calling iio_channel_release_all(). Add resource managed version (devm_*) of these APIs so that if client calls the devm_iio_channel_get_all() then it need not to release it explicitly, it can be done by managed device framework when driver get un-binded. This reduces the code in error path and also need of .remove callback in some cases. Signed-off-by: Laxman Dewangan Signed-off-by: Jonathan Cameron --- drivers/iio/inkern.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/iio/consumer.h | 26 ++++++++++++++++++++++++++ 2 files changed, 62 insertions(+) diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c index 9fd8934c1887..c4757e6367e7 100644 --- a/drivers/iio/inkern.c +++ b/drivers/iio/inkern.c @@ -489,6 +489,42 @@ void iio_channel_release_all(struct iio_channel *channels) } EXPORT_SYMBOL_GPL(iio_channel_release_all); +static void devm_iio_channel_free_all(struct device *dev, void *res) +{ + struct iio_channel *channels = *(struct iio_channel **)res; + + iio_channel_release_all(channels); +} + +struct iio_channel *devm_iio_channel_get_all(struct device *dev) +{ + struct iio_channel **ptr, *channels; + + ptr = devres_alloc(devm_iio_channel_free_all, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + channels = iio_channel_get_all(dev); + if (IS_ERR(channels)) { + devres_free(ptr); + return channels; + } + + *ptr = channels; + devres_add(dev, ptr); + + return channels; +} +EXPORT_SYMBOL_GPL(devm_iio_channel_get_all); + +void devm_iio_channel_release_all(struct device *dev, + struct iio_channel *channels) +{ + WARN_ON(devres_release(dev, devm_iio_channel_free_all, + devm_iio_channel_match, channels)); +} +EXPORT_SYMBOL_GPL(devm_iio_channel_release_all); + static int iio_channel_read(struct iio_channel *chan, int *val, int *val2, enum iio_chan_info_enum info) { diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h index e1e033d6a81f..3d672f72e7ec 100644 --- a/include/linux/iio/consumer.h +++ b/include/linux/iio/consumer.h @@ -92,6 +92,32 @@ struct iio_channel *iio_channel_get_all(struct device *dev); */ void iio_channel_release_all(struct iio_channel *chan); +/** + * devm_iio_channel_get_all() - Resource managed version of + * iio_channel_get_all(). + * @dev: Pointer to consumer device. + * + * Returns a pointer to negative errno if it is not able to get the iio channel + * otherwise returns an array of iio_channel structures terminated with one with + * null iio_dev pointer. + * + * This function is used by fairly generic consumers to get all the + * channels registered as having this consumer. + * + * The allocated iio channels are automatically released when the device is + * unbounded. + */ +struct iio_channel *devm_iio_channel_get_all(struct device *dev); + +/** + * devm_iio_channel_release_all() - Resource managed version of + * iio_channel_release_all(). + * @dev: Pointer to consumer device for which resource + * is allocared. + * @chan: Array channel to be released. + */ +void devm_iio_channel_release_all(struct device *dev, struct iio_channel *chan); + struct iio_cb_buffer; /** * iio_channel_get_all_cb() - register callback for triggered capture