hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

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>
This commit is contained in:
Lars-Peter Clausen 2015-10-13 18:10:27 +02:00 committed by Jonathan Cameron
parent b440655b89
commit e18a2ad45c
2 changed files with 43 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
drivers/iio/industrialio-buffer.c
View File

@ -568,6 +568,22 @@ static void iio_buffer_deactivate_all(struct iio_dev *indio_dev)
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_verify_update(struct iio_dev *indio_dev,
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 @@ static int iio_enable_buffers(struct iio_dev *indio_dev,
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 @@ static int iio_enable_buffers(struct iio_dev *indio_dev,
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 @@ err_undo_config:
static int iio_disable_buffers(struct iio_dev *indio_dev)
{
struct iio_buffer *buffer;
int ret = 0;
int ret2;
@ -798,6 +826,12 @@ static int iio_disable_buffers(struct iio_dev *indio_dev)
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) {

8
include/linux/iio/buffer.h
View File

@ -33,6 +33,11 @@ struct iio_buffer;
* storage.
* @set_bytes_per_datum:set number of bytes per datum
* @set_length: set number of datums in buffer
* @enable: called if the buffer is attached to a device and the
* device starts sampling. Calls are balanced with
* @disable.
* @disable: called if the buffer is attached to a device and the
* device stops sampling. Calles are balanced with @enable.
* @release: called when the last reference to the buffer is dropped,
* should free all resources allocated by the buffer.
* @modes: Supported operating modes by this buffer type
@ -58,6 +63,9 @@ struct iio_buffer_access_funcs {
int (*set_bytes_per_datum)(struct iio_buffer *buffer, size_t bpd);
int (*set_length)(struct iio_buffer *buffer, int length);
int (*enable)(struct iio_buffer *buffer, struct iio_dev *indio_dev);
int (*disable)(struct iio_buffer *buffer, struct iio_dev *indio_dev);
void (*release)(struct iio_buffer *buffer);
unsigned int modes;