iio: Add buffer enable/disable callbacks
This patch adds a enable and disable callback that is called when the
buffer is enabled/disabled. This can be used by buffer implementations that
need to do some setup or teardown work. E.g. a DMA based buffer can use
this to start/stop the DMA transfer.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index 98a6447..a4b164a 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -568,6 +568,22 @@
iio_buffer_deactivate(buffer);
}
+static int iio_buffer_enable(struct iio_buffer *buffer,
+ struct iio_dev *indio_dev)
+{
+ if (!buffer->access->enable)
+ return 0;
+ return buffer->access->enable(buffer, indio_dev);
+}
+
+static int iio_buffer_disable(struct iio_buffer *buffer,
+ struct iio_dev *indio_dev)
+{
+ if (!buffer->access->disable)
+ return 0;
+ return buffer->access->disable(buffer, indio_dev);
+}
+
static void iio_buffer_update_bytes_per_datum(struct iio_dev *indio_dev,
struct iio_buffer *buffer)
{
@@ -719,6 +735,7 @@
static int iio_enable_buffers(struct iio_dev *indio_dev,
struct iio_device_config *config)
{
+ struct iio_buffer *buffer;
int ret;
indio_dev->active_scan_mask = config->scan_mask;
@@ -753,6 +770,12 @@
indio_dev->info->hwfifo_set_watermark(indio_dev,
config->watermark);
+ list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
+ ret = iio_buffer_enable(buffer, indio_dev);
+ if (ret)
+ goto err_disable_buffers;
+ }
+
indio_dev->currentmode = config->mode;
if (indio_dev->setup_ops->postenable) {
@@ -760,12 +783,16 @@
if (ret) {
dev_dbg(&indio_dev->dev,
"Buffer not started: postenable failed (%d)\n", ret);
- goto err_run_postdisable;
+ goto err_disable_buffers;
}
}
return 0;
+err_disable_buffers:
+ list_for_each_entry_continue_reverse(buffer, &indio_dev->buffer_list,
+ buffer_list)
+ iio_buffer_disable(buffer, indio_dev);
err_run_postdisable:
indio_dev->currentmode = INDIO_DIRECT_MODE;
if (indio_dev->setup_ops->postdisable)
@@ -778,6 +805,7 @@
static int iio_disable_buffers(struct iio_dev *indio_dev)
{
+ struct iio_buffer *buffer;
int ret = 0;
int ret2;
@@ -798,6 +826,12 @@
ret = ret2;
}
+ list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
+ ret2 = iio_buffer_disable(buffer, indio_dev);
+ if (ret2 && !ret)
+ ret = ret2;
+ }
+
indio_dev->currentmode = INDIO_DIRECT_MODE;
if (indio_dev->setup_ops->postdisable) {