From c1b91566580c245cf1147745d174be5e059ace6b Mon Sep 17 00:00:00 2001 From: Paul Cercueil Date: Fri, 19 Apr 2024 10:25:37 +0200 Subject: [PATCH] iio: buffer-dmaengine: Support specifying buffer direction 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. Signed-off-by: Paul Cercueil Reviewed-by: Alexandru Ardelean Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240419-iio-backend-axi-dac-v4-4-5ca45b4de294@analog.com Signed-off-by: Jonathan Cameron --- .../buffer/industrialio-buffer-dmaengine.c | 44 +++++++++++++------ include/linux/iio/buffer-dmaengine.h | 25 ++++++++--- 2 files changed, 49 insertions(+), 20 deletions(-) diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c index df05d66afff9..951012651018 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; @@ -229,9 +240,10 @@ void iio_dmaengine_buffer_free(struct iio_buffer *buffer) } EXPORT_SYMBOL_NS_GPL(iio_dmaengine_buffer_free, IIO_DMAENGINE_BUFFER); -struct iio_buffer *iio_dmaengine_buffer_setup(struct device *dev, - struct iio_dev *indio_dev, - const char *channel) +struct iio_buffer *iio_dmaengine_buffer_setup_ext(struct device *dev, + struct iio_dev *indio_dev, + const char *channel, + enum iio_buffer_direction dir) { struct iio_buffer *buffer; int ret; @@ -242,6 +254,8 @@ struct iio_buffer *iio_dmaengine_buffer_setup(struct device *dev, indio_dev->modes |= INDIO_BUFFER_HARDWARE; + buffer->direction = dir; + ret = iio_device_attach_buffer(indio_dev, buffer); if (ret) { iio_dmaengine_buffer_free(buffer); @@ -250,7 +264,7 @@ struct iio_buffer *iio_dmaengine_buffer_setup(struct device *dev, return buffer; } -EXPORT_SYMBOL_NS_GPL(iio_dmaengine_buffer_setup, IIO_DMAENGINE_BUFFER); +EXPORT_SYMBOL_NS_GPL(iio_dmaengine_buffer_setup_ext, IIO_DMAENGINE_BUFFER); static void __devm_iio_dmaengine_buffer_free(void *buffer) { @@ -258,30 +272,32 @@ static void __devm_iio_dmaengine_buffer_free(void *buffer) } /** - * devm_iio_dmaengine_buffer_setup() - Setup a DMA buffer for an IIO device + * devm_iio_dmaengine_buffer_setup_ext() - Setup a DMA buffer for an IIO device * @dev: Parent device for the buffer * @indio_dev: IIO device to which to attach this buffer. * @channel: DMA channel name, typically "rx". + * @dir: Direction of buffer (in or out) * * This allocates a new IIO buffer with devm_iio_dmaengine_buffer_alloc() * and attaches it to an IIO device with iio_device_attach_buffer(). * It also appends the INDIO_BUFFER_HARDWARE mode to the supported modes of the * IIO device. */ -int devm_iio_dmaengine_buffer_setup(struct device *dev, - struct iio_dev *indio_dev, - const char *channel) +int devm_iio_dmaengine_buffer_setup_ext(struct device *dev, + struct iio_dev *indio_dev, + const char *channel, + enum iio_buffer_direction dir) { struct iio_buffer *buffer; - buffer = iio_dmaengine_buffer_setup(dev, indio_dev, channel); + buffer = iio_dmaengine_buffer_setup_ext(dev, indio_dev, channel, dir); if (IS_ERR(buffer)) return PTR_ERR(buffer); return devm_add_action_or_reset(dev, __devm_iio_dmaengine_buffer_free, buffer); } -EXPORT_SYMBOL_NS_GPL(devm_iio_dmaengine_buffer_setup, IIO_DMAENGINE_BUFFER); +EXPORT_SYMBOL_NS_GPL(devm_iio_dmaengine_buffer_setup_ext, IIO_DMAENGINE_BUFFER); MODULE_AUTHOR("Lars-Peter Clausen "); MODULE_DESCRIPTION("DMA buffer for the IIO framework"); diff --git a/include/linux/iio/buffer-dmaengine.h b/include/linux/iio/buffer-dmaengine.h index acb60f9a3fff..81d9a19aeb91 100644 --- a/include/linux/iio/buffer-dmaengine.h +++ b/include/linux/iio/buffer-dmaengine.h @@ -7,15 +7,28 @@ #ifndef __IIO_DMAENGINE_H__ #define __IIO_DMAENGINE_H__ +#include + struct iio_dev; struct device; void iio_dmaengine_buffer_free(struct iio_buffer *buffer); -struct iio_buffer *iio_dmaengine_buffer_setup(struct device *dev, - struct iio_dev *indio_dev, - const char *channel); -int devm_iio_dmaengine_buffer_setup(struct device *dev, - struct iio_dev *indio_dev, - const char *channel); +struct iio_buffer *iio_dmaengine_buffer_setup_ext(struct device *dev, + struct iio_dev *indio_dev, + const char *channel, + enum iio_buffer_direction dir); + +#define iio_dmaengine_buffer_setup(dev, indio_dev, channel) \ + iio_dmaengine_buffer_setup_ext(dev, indio_dev, channel, \ + IIO_BUFFER_DIRECTION_IN) + +int devm_iio_dmaengine_buffer_setup_ext(struct device *dev, + struct iio_dev *indio_dev, + const char *channel, + enum iio_buffer_direction dir); + +#define devm_iio_dmaengine_buffer_setup(dev, indio_dev, channel) \ + devm_iio_dmaengine_buffer_setup_ext(dev, indio_dev, channel, \ + IIO_BUFFER_DIRECTION_IN) #endif