Re: [PATCH 05/15] iio: buffer-dmaengine: Support specifying buffer direction

On Mon, Nov 15, 2021 at 4:20 PM Paul Cercueil paul@crapouillou.net wrote:

Update the devm_iio_dmaengine_buffer_setup() function to support specifying the buffer direction.

Update the iio_dmaengine_buffer_submit() function to handle input buffers as well as output buffers.

Reviewed-by: Alexandru Ardelean ardeleanalex@gmail.com

Signed-off-by: Paul Cercueil paul@crapouillou.net

drivers/iio/adc/adi-axi-adc.c | 3 ++- .../buffer/industrialio-buffer-dmaengine.c | 24 +++++++++++++++---- include/linux/iio/buffer-dmaengine.h | 5 +++- 3 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c index a73e3c2d212f..0a6f2c32b1b9 100644 --- a/drivers/iio/adc/adi-axi-adc.c +++ b/drivers/iio/adc/adi-axi-adc.c @@ -113,7 +113,8 @@ static int adi_axi_adc_config_dma_buffer(struct device *dev, dma_name = "rx";

    return devm_iio_dmaengine_buffer_setup(indio_dev->dev.parent,

•                                          indio_dev, dma_name);
  

•                                          indio_dev, dma_name,
  

•                                          IIO_BUFFER_DIRECTION_IN);
  

}

static int adi_axi_adc_read_raw(struct iio_dev *indio_dev, diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c index f8ce26a24c57..ac26b04aa4a9 100644 --- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c +++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c @@ -64,14 +64,25 @@ static int iio_dmaengine_buffer_submit_block(struct iio_dma_buffer_queue *queue, struct dmaengine_buffer *dmaengine_buffer = iio_buffer_to_dmaengine_buffer(&queue->buffer); struct dma_async_tx_descriptor *desc;

•   enum dma_transfer_direction dma_dir;
  

•   size_t max_size;
    dma_cookie_t cookie;
  
  

•   block->bytes_used = min(block->size, dmaengine_buffer->max_size);
  

•   block->bytes_used = round_down(block->bytes_used,
  

•                   dmaengine_buffer->align);
  

•   max_size = min(block->size, dmaengine_buffer->max_size);
  

•   max_size = round_down(max_size, dmaengine_buffer->align);
  

•   if (queue->buffer.direction == IIO_BUFFER_DIRECTION_IN) {
  

•           block->bytes_used = max_size;
  

•           dma_dir = DMA_DEV_TO_MEM;
  

•   } else {
  

•           dma_dir = DMA_MEM_TO_DEV;
  

•   }
  

•   if (!block->bytes_used || block->bytes_used > max_size)
  

•           return -EINVAL;
  
    desc = dmaengine_prep_slave_single(dmaengine_buffer->chan,
  

•           block->phys_addr, block->bytes_used, DMA_DEV_TO_MEM,
  

•           block->phys_addr, block->bytes_used, dma_dir,
            DMA_PREP_INTERRUPT);
    if (!desc)
            return -ENOMEM;
  

@@ -275,7 +286,8 @@ static struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev, */ int devm_iio_dmaengine_buffer_setup(struct device *dev, struct iio_dev *indio_dev,

•                               const char *channel)
  

•                               const char *channel,
  

•                               enum iio_buffer_direction dir)
  

{ struct iio_buffer *buffer;

@@ -286,6 +298,8 @@ int devm_iio_dmaengine_buffer_setup(struct device *dev,

    indio_dev->modes |= INDIO_BUFFER_HARDWARE;

•   buffer->direction = dir;
  

•   return iio_device_attach_buffer(indio_dev, buffer);
  

} EXPORT_SYMBOL_GPL(devm_iio_dmaengine_buffer_setup); diff --git a/include/linux/iio/buffer-dmaengine.h b/include/linux/iio/buffer-dmaengine.h index 5c355be89814..538d0479cdd6 100644 --- a/include/linux/iio/buffer-dmaengine.h +++ b/include/linux/iio/buffer-dmaengine.h @@ -7,11 +7,14 @@ #ifndef __IIO_DMAENGINE_H__ #define __IIO_DMAENGINE_H__

+#include <linux/iio/buffer.h>

struct iio_dev; struct device;

int devm_iio_dmaengine_buffer_setup(struct device *dev, struct iio_dev *indio_dev,

•                               const char *channel);
  

•                               const char *channel,
  

•                               enum iio_buffer_direction dir);
  
  

#endif

2.33.0