The existing APIs for requesting TX and RX DMA channels rely on parsing a device-tree node to obtain the Channel/Thread IDs from their names. However, it is possible to know the thread IDs by alternative means such as being informed by Firmware on a remote core via RPMsg regarding the allocated TX/RX DMA channel thread IDs. In such cases, the driver can be probed by non device-tree methods such as RPMsg-bus, due to which it is not necessary that the device using the DMA has a device-tree node corresponding to it. Thus, add APIs to enable the driver to make use of the existing DMA APIs even when there's no device-tree node. Additionally, since the name of the device for the remote RX channel is being set purely on the basis of the RX channel ID itself, it can result in duplicate names when multiple flows are used on the same channel. Avoid name duplication by including the flow in the name. Series is based on linux-next tagged next-20231215. v2: https://lore.kernel.org/r/20231212111011.1401641-1-s-vadapalli@xxxxxx/ Changes since v2: - Rebased series on linux-next tagged next-20231215. - Renamed the function "k3_udma_glue_request_tx_chn_by_id()" to "k3_udma_glue_request_tx_chn_for_thread_id()" as suggested by: Péter Ujfalusi <peter.ujfalusi@xxxxxxxxx> - Similar to the above change, I have also renamed the function "k3_udma_glue_request_remote_rx_chn_by_id()" to "k3_udma_glue_request_remote_rx_chn_for_thread_id()". - Updated the function prototypes in include/linux/dma/k3-udma-glue.h accordingly. - Updated the commit messages for patches 3/4 and 4/4 to match the changes made to the function names. v1: https://lore.kernel.org/r/20231114083906.3143548-1-s-vadapalli@xxxxxx/ Changes since v1: - Rebased series on linux-next tagged next-20231212. - Updated commit messages with details regarding the use-case for which the newly added APIs will be required. - Removed unnecessary return value check within "of_k3_udma_glue_parse_chn()" function in patch 1, since it will fall through to "out_put_spec" anyway. - Removed unnecessary return value check within "of_k3_udma_glue_parse_chn_by_id()" function in patch 1, since it will fall through to "out_put_spec" anyway. - Moved patch 4 of v1 series to patch 2 of current series. RFC Series: https://lore.kernel.org/r/20231111121555.2656760-1-s-vadapalli@xxxxxx/ Changes since RFC Series: - Rebased patches 1, 2 and 3 on linux-next tagged next-20231114. - Added patch 4 to the series. Regards, Siddharth. Siddharth Vadapalli (4): dmaengine: ti: k3-udma-glue: Add function to parse channel by ID dmaengine: ti: k3-udma-glue: Update name for remote RX channel device dmaengine: ti: k3-udma-glue: Add function to request TX chan for thread ID dmaengine: ti: k3-udma-glue: Add function to request RX chan for thread ID drivers/dma/ti/k3-udma-glue.c | 306 ++++++++++++++++++++++--------- include/linux/dma/k3-udma-glue.h | 10 + 2 files changed, 229 insertions(+), 87 deletions(-) -- 2.34.1
