kernel.git/drivers/iio/buffer/industrialio-buffer-dmaengine.c, branch linux-6.12.y

iio: buffer-dmaengine: enable .get_dma_dev()

2025-12-06T21:24:57Z

commit 3db847df994d475db7812dde90376f2848bcd30a upstream. Wire up the .get_dma_dev() callback to use the DMA buffer infrastructure's implementation. This ensures that DMABUF operations use the correct DMA device for mapping, which is essential for proper operation on systems where memory is mapped above the 32-bit range. Without this callback, the core would fall back to using the IIO device's parent, which may not have the appropriate DMA mask configuration for high memory access. Fixes: 7a86d469983a ("iio: buffer-dmaengine: Support new DMABUF based userspace API") Reviewed-by: David Lechner Signed-off-by: Nuno Sá Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Greg Kroah-Hartman

Merge 6.11-rc7 into char-misc-next

2024-09-09T06:36:23Z

We need the char-misc fixes in here as well. Signed-off-by: Greg Kroah-Hartman

iio: buffer-dma: Move exports into IIO_DMA_BUFFER namespace

2024-08-03T09:13:43Z

Avoid unnecessary pollution of the global symbol namespace and move global APIs into a specific namespace. Import that into the places that use them Signed-off-by: Nuno Sa Link: https://patch.msgid.link/20240726-dev-iio-dma-buf-mod-namespace-v1-1-8877cfe7f68e@analog.com Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: fix releasing dma channel on error

2024-07-29T19:31:23Z

If dma_get_slave_caps() fails, we need to release the dma channel before returning an error to avoid leaking the channel. Fixes: 2d6ca60f3284 ("iio: Add a DMAengine framework based buffer") Signed-off-by: David Lechner Link: https://patch.msgid.link/20240723-iio-fix-dmaengine-free-on-error-v1-1-2c7cbc9b92ff@baylibre.com Cc: Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: Support new DMABUF based userspace API

2024-06-30T10:29:28Z

Use the functions provided by the buffer-dma core to implement the DMABUF userspace API in the buffer-dmaengine IIO buffer implementation. Since we want to be able to transfer an arbitrary number of bytes and not necesarily the full DMABUF, the associated scatterlist is converted to an array of DMA addresses + lengths, which is then passed to dmaengine_prep_slave_dma_array(). Signed-off-by: Paul Cercueil Co-developed-by: Nuno Sa Signed-off-by: Nuno Sa Link: https://patch.msgid.link/20240620122726.41232-6-paul@crapouillou.net Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: Enable write support

2024-04-20T14:41:32Z

Use the iio_dma_buffer_write() and iio_dma_buffer_space_available() functions provided by the buffer-dma core, to enable write support in the buffer-dmaengine code. 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-v4-5-5ca45b4de294@analog.com Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: Support specifying buffer direction

2024-04-20T14:41:14Z

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

iio: buffer-dma: Rename iio_dma_buffer_data_available()

2024-04-20T14:36:41Z

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: add iio_dmaengine_buffer_setup()

2024-04-20T14:36:41Z

This brings the DMA buffer API more in line with what we have in the triggered buffer. There's no need of having both devm_iio_dmaengine_buffer_setup() and devm_iio_dmaengine_buffer_alloc(). Hence we introduce the new iio_dmaengine_buffer_setup() that together with devm_iio_dmaengine_buffer_setup() should be all we need. Note that as part of this change iio_dmaengine_buffer_alloc() is again static and the axi-adc was updated accordingly. Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240419-iio-backend-axi-dac-v4-1-5ca45b4de294@analog.com Signed-off-by: Jonathan Cameron

iio: buffer-dmaengine: export buffer alloc and free functions

2024-02-19T19:32:21Z

Export iio_dmaengine_buffer_free() and iio_dmaengine_buffer_alloc(). This is in preparation of introducing IIO backends support. This will allow us to allocate a buffer and control it's lifetime from a device different from the one holding the DMA firmware properties. Effectively, in this case the struct device holding the firmware information about the DMA channels is not the same as iio_dev->dev.parent (typical case). While at it, namespace the buffer-dmaengine exports and update the current user of these buffers. Signed-off-by: Nuno Sa Link: https://lore.kernel.org/r/20240210-iio-backend-v11-4-f5242a5fb42a@analog.com Reviewed-by: Andy Shevchenko Signed-off-by: Jonathan Cameron