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 <ldewangan@xxxxxxxxxx>
---
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 18e623f..8c1abfe 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 e1e033d..3d672f7 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
--
2.1.4
--
To unsubscribe from this list: send the line "unsubscribe linux-doc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
