kernel/linux.git/Documentation/driver-api/dmaengine, branch v6.19.11

Merge tag 'dmaengine-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine

2025-06-05T15:49:30+00:00

Pull dmaengine updates from Vinod Koul: "A fairly small update for the dmaengine subsystem. This has a new ARM dmaengine driver and couple of new device support and few driver changes: New support: - Renesas RZ/V2H(P) dma support for r9a09g057 - Arm DMA-350 driver - Tegra Tegra264 ADMA support Updates: - AMD ptdma driver code removal and optimizations - Freescale edma error interrupt handler support" * tag 'dmaengine-6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (27 commits) dmaengine: idxd: Remove unused pointer and macro arm64: dts: renesas: r9a09g057: Add DMAC nodes dmaengine: sh: rz-dmac: Add RZ/V2H(P) support dmaengine: sh: rz-dmac: Allow for multiple DMACs irqchip/renesas-rzv2h: Add rzv2h_icu_register_dma_req() dt-bindings: dma: rz-dmac: Document RZ/V2H(P) family of SoCs dt-bindings: dma: rz-dmac: Restrict properties for RZ/A1H dmaengine: idxd: Narrow the restriction on BATCH to ver. 1 only dmaengine: ti: Add NULL check in udma_probe() fsldma: Set correct dma_mask based on hw capability dmaengine: idxd: Check availability of workqueue allocated by idxd wq driver before using dmaengine: xilinx_dma: Set dma_device directions dmaengine: tegra210-adma: Add Tegra264 support dt-bindings: Document Tegra264 ADMA support dmaengine: dw-edma: Add HDMA NATIVE map check dmaegnine: fsl-edma: add edma error interrupt handler dt-bindings: dma: fsl-edma: increase maxItems of interrupts and interrupt-names dmaengine: ARM_DMA350 should depend on ARM/ARM64 dt-bindings: dma: qcom,bam: Document dma-coherent property dmaengine: Add Arm DMA-350 driver ...

docs: dmaengine: add explanation for DMA_ASYNC_TX capability

2025-05-07T07:02:57+00:00

This patch replaces the TODO for DMA_ASYNC_TX in the DMA engine provider documentation. The flag is automatically set by the DMA framework when a device supports key asynchronous memory-to-memory operations such as memcpy, memset, xor, pq, xor_val, and pq_val. It must not be set by drivers directly. Signed-off-by: Kendra Moore Signed-off-by: Jonathan Corbet Message-ID: <20250421010205.84719-1-kendra.j.moore3443@gmail.com>

Documentation: dmaengine: Correct reference to glReadPixels()

2025-04-07T05:33:47+00:00

The author very likely meant "glReadPixels()" instead of "glReadpielx()", which does not appear in the OpenGL API. https://registry.khronos.org/OpenGL-Refpages/gl4/html/glReadPixels.xhtml Signed-off-by: Nathan Lynch Link: https://lore.kernel.org/r/20241010-doc-dmaengine-glreadpixels-v1-1-8202e5834b13@amd.com Signed-off-by: Vinod Koul

Documentation: dmaengine: Document new dma_vec API

2024-06-21T10:01:57+00:00

Document the dmaengine_prep_peripheral_dma_vec() API function, the device_prep_peripheral_dma_vec() backend function, and the dma_vec struct. Signed-off-by: Paul Cercueil Reviewed-by: Bagas Sanjaya Link: https://lore.kernel.org/r/20240620122726.41232-8-paul@crapouillou.net Signed-off-by: Vinod Koul

Documentation: driver-api: correct spelling

2023-02-02T18:05:16+00:00

Correct spelling problems for Documentation/driver-api/ as reported by codespell. Signed-off-by: Randy Dunlap Cc: Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org Cc: Vishal Verma Cc: Dave Jiang Cc: nvdimm@lists.linux.dev Cc: Vinod Koul Cc: dmaengine@vger.kernel.org Cc: linux-raid@vger.kernel.org Cc: linux-usb@vger.kernel.org Acked-by: Dan Williams Acked-by: Song Liu Acked-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20230129231053.20863-3-rdunlap@infradead.org Signed-off-by: Jonathan Corbet

dmaengine: remove DMA_MEMCPY_SG once again

2022-06-27T06:31:40+00:00

This was removed before due to the complete lack of users, but 3218910fd585 ("dmaengine: Add core function and capability check for DMA_MEMCPY_SG") and 29cf37fa6dd9 ("dmaengine: Add consumer for the new DMA_MEMCPY_SG API function.") added it back despite still not having any users whatsoever. Fixes: 3218910fd585 ("dmaengine: Add core function and capability check for DMA_MEMCPY_SG") Fixes: 29cf37fa6dd9 ("dmaengine: Add consumer for the new DMA_MEMCPY_SG API function.") Signed-off-by: Christoph Hellwig Acked-by: Michal Simek Link: https://lore.kernel.org/r/20220606074733.622616-1-hch@lst.de Signed-off-by: Vinod Koul

dmaengine: Document dmaengine_prep_dma_memset

2022-04-20T11:58:12+00:00

Document this function to make clear the expected behavior of the 'value' parameter. It was intended to match the behavior of POSIX memset as laid out here: https://lore.kernel.org/dmaengine/YejrA5ZWZ3lTRO%2F1@matsya/ Signed-off-by: Ben Walker Link: https://lore.kernel.org/r/20220301182551.883474-2-benjamin.walker@intel.com Signed-off-by: Vinod Koul

dmaengine: Clarify cyclic transfer residue documentation

2022-04-11T13:45:52+00:00

The current documentation for the residue reported in a cyclic transfer case mentions that the reported residue should be relative to the current period only. However the definition of DMA_RESIDUE_GRANULARITY_SEGMENT specifies that the residue should be updated after each period for a cyclic transfer, which is in direct contradiction. Moreover the pcm_dmaengine common code uses the residue relative to the whole cyclic buffer size, not one period. Correct the residue-related documentation to reflect this. Signed-off-by: Paul Kocialkowski Link: https://lore.kernel.org/r/20220331134114.703782-1-paul.kocialkowski@bootlin.com Signed-off-by: Vinod Koul

Documentation: dmaengine: Correctly describe dmatest with channel unset

2021-11-22T07:01:00+00:00

Currently the documentation states that channels must be configured before running the dmatest. This has not been true since commit 6b41030fdc79 ("dmaengine: dmatest: Restore default for channel"). Fix accordingly. Fixes: 6b41030fdc79 ("dmaengine: dmatest: Restore default for channel") Signed-off-by: Daniel Thompson Link: https://lore.kernel.org/r/20211118100952.27268-3-daniel.thompson@linaro.org Signed-off-by: Vinod Koul

Documentation: dmaengine: Add a description of what dmatest does

2021-11-22T07:01:00+00:00

Currently it can difficult to determine what dmatest does without reading the source code. Let's add a description. The description is taken mostly from the patch header of commit 4a776f0aa922 ("dmatest: Simple DMA memcpy test client"). It has been edited and updated slightly. Nevertheless the new text was largely written by Haarvard Skinnemoen and was copied from another patch, already committed to the kernel, which has Haarvard's SoB: attached to it. Signed-off-by: Daniel Thompson Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20211118100952.27268-2-daniel.thompson@linaro.org Signed-off-by: Vinod Koul