kernel/linux.git/include/linux/iio/buffer-dma.h, branch v7.0-rc7

iio: buffer-dma: Fix coding style complains

2025-12-21T12:00:27+00:00

Just making sure checkpatch is happy. No functional change intended. Signed-off-by: Nuno Sá Signed-off-by: Jonathan Cameron

iio: buffer-dma: Turn iio_dma_buffer_init() void

2025-12-21T11:58:01+00:00

iio_dma_buffer_init() always return 0. Therefore there's no point in returning int. While at it, fix a mismatch between the function declaration and definition regarding the struct device (dma_dev != dev). Signed-off-by: Nuno Sá Signed-off-by: Jonathan Cameron

iio: buffer-dma: support getting the DMA channel

2025-10-13T07:38:08+00:00

Implement the .get_dma_dev() callback for DMA buffers by returning the device that owns the DMA channel. This allows the core DMABUF infrastructure to properly map DMA buffers using the correct device, avoiding the need for bounce buffers on systems where memory is mapped above the 32-bit range. The function returns the DMA queue's device, which is the actual device responsible for DMA operations in buffer-dma implementations. Cc: stable@vger.kernel.org Reviewed-by: David Lechner Signed-off-by: Nuno Sá Signed-off-by: Jonathan Cameron

iio: buffer-dma: Enable support for DMABUFs

2024-06-30T10:29:24+00:00

Implement iio_dma_buffer_attach_dmabuf(), iio_dma_buffer_detach_dmabuf() and iio_dma_buffer_transfer_dmabuf(), which can then be used by the IIO DMA buffer implementations. Signed-off-by: Paul Cercueil Co-developed-by: Nuno Sa Signed-off-by: Nuno Sa Link: https://patch.msgid.link/20240620122726.41232-5-paul@crapouillou.net Signed-off-by: Jonathan Cameron

iio: buffer-dma: Enable buffer write support

2024-04-20T14:36:41+00:00

Adding write support to the buffer-dma code is easy - the write() function basically needs to do the exact same thing as the read() function: dequeue a block, read or write the data, enqueue the block when entirely processed. Therefore, the iio_buffer_dma_read() and the new iio_buffer_dma_write() now both call a function iio_buffer_dma_io(), which will perform this task. Note that we preemptively reset block->bytes_used to the buffer's size in iio_dma_buffer_request_update(), as in the future the iio_dma_buffer_enqueue() function won't reset it. 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-v4-3-5ca45b4de294@analog.com Signed-off-by: Jonathan Cameron

iio: buffer-dma: Rename iio_dma_buffer_data_available()

2024-04-20T14:36:41+00:00

Change its name to iio_dma_buffer_usage(), as this function can be used both for the .data_available and the .space_available callbacks. Signed-off-by: Paul Cercueil Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240419-iio-backend-axi-dac-v4-2-5ca45b4de294@analog.com Signed-off-by: Jonathan Cameron

iio: buffer-dma: Get rid of outgoing queue

2023-12-21T11:28:47+00:00

The buffer-dma code was using two queues, incoming and outgoing, to manage the state of the blocks in use. While this totally works, it adds some complexity to the code, especially since the code only manages 2 blocks. It is much easier to just check each block's state manually, and keep a counter for the next block to dequeue. Since the new DMABUF based API wouldn't use the outgoing queue anyway, getting rid of it now makes the upcoming changes simpler. With this change, the IIO_BLOCK_STATE_DEQUEUED is now useless, and can be removed. Signed-off-by: Paul Cercueil Link: https://lore.kernel.org/r/20231219175009.65482-2-paul@crapouillou.net Signed-off-by: Jonathan Cameron

iio: buffer-dma: Remove unused iio_buffer_block struct

2021-11-27T15:12:01+00:00

This structure was never used anywhere, so it can safely be dropped. It will later be re-introduced as a different structure in a different header. Signed-off-by: Paul Cercueil Reviewed-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20211115141925.60164-3-paul@crapouillou.net Signed-off-by: Jonathan Cameron

iio: dma-buffer: Cleanup buffer.h/buffer_impl.h includes

2020-04-19T15:56:31+00:00

The IIO DMA buffer is a DMA buffer implementation. As such it should include buffer_impl.h rather than buffer.h. The include to buffer.h in buffer-dma.h should be buffer_impl.h so it has access to the struct iio_buffer definition. The code currently only works because all places that use buffer-dma.h include buffer_impl.h before it. The include to buffer.h in industrialio-buffer-dma.c can be removed since those file does not reference any of buffer consumer functions. Signed-off-by: Lars-Peter Clausen Tested-by: Alexandru Ardelean Signed-off-by: Jonathan Cameron

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 177

2019-05-30T18:29:19+00:00

Based on 1 normalized pattern(s): licensed under the gpl 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 135 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Reviewed-by: Alexios Zavras Reviewed-by: Steve Winslow Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528170026.071193225@linutronix.de Signed-off-by: Greg Kroah-Hartman