iio: core: Add devm_ APIs for iio_channel_{get,release}
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() and release it by calling iio_channel_release().
Add resource managed version (devm_*) of these APIs so that if client
calls the devm_iio_channel_get() 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 <ldewangan@nvidia.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index 2fc7928..9fd8934 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -356,6 +356,54 @@
}
EXPORT_SYMBOL_GPL(iio_channel_release);
+static void devm_iio_channel_free(struct device *dev, void *res)
+{
+ struct iio_channel *channel = *(struct iio_channel **)res;
+
+ iio_channel_release(channel);
+}
+
+static int devm_iio_channel_match(struct device *dev, void *res, void *data)
+{
+ struct iio_channel **r = res;
+
+ if (!r || !*r) {
+ WARN_ON(!r || !*r);
+ return 0;
+ }
+
+ return *r == data;
+}
+
+struct iio_channel *devm_iio_channel_get(struct device *dev,
+ const char *channel_name)
+{
+ struct iio_channel **ptr, *channel;
+
+ ptr = devres_alloc(devm_iio_channel_free, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ channel = iio_channel_get(dev, channel_name);
+ if (IS_ERR(channel)) {
+ devres_free(ptr);
+ return channel;
+ }
+
+ *ptr = channel;
+ devres_add(dev, ptr);
+
+ return channel;
+}
+EXPORT_SYMBOL_GPL(devm_iio_channel_get);
+
+void devm_iio_channel_release(struct device *dev, struct iio_channel *channel)
+{
+ WARN_ON(devres_release(dev, devm_iio_channel_free,
+ devm_iio_channel_match, channel));
+}
+EXPORT_SYMBOL_GPL(devm_iio_channel_release);
+
struct iio_channel *iio_channel_get_all(struct device *dev)
{
const char *name;