Commit 49b1c21f authored by Amelie Delaunay's avatar Amelie Delaunay Committed by Vinod Koul
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dmaengine: stm32-dma3: defer channel registration to specify channel name 



On STM32 DMA3, channels can be reserved, so they are non available for
Linux. This non-availability creates a mismatch between dma_chan id and
DMA3 channel id.

Use dma_async_device_channel_register() to register the channels
after controller registration and change the default channel name, so that
it can match the name in the Reference Manual and ease requesting a channel
thanks to its name.

Signed-off-by: default avatarAmelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20240531150712.2503554-12-amelie.delaunay@foss.st.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 10b8e0fd

drivers/dma/stm32/stm32-dma3.c

+14 −5
Original line number Diff line number Diff line
@@ -1732,9 +1732,6 @@ static int stm32_dma3_probe(struct platform_device *pdev) 
		chan->fifo_size = get_chan_hwcfg(i, G_FIFO_SIZE(i), hwcfgr);

		/* If chan->fifo_size > 0 then half of the fifo size, else no burst when no FIFO */

		chan->max_burst = (chan->fifo_size) ? (1 << (chan->fifo_size + 1)) / 2 : 0;

		chan->vchan.desc_free = stm32_dma3_chan_vdesc_free;



		vchan_init(&chan->vchan, dma_dev);

	}



	ret = dmaenginem_async_device_register(dma_dev);
@@ -1742,14 +1739,26 @@ static int stm32_dma3_probe(struct platform_device *pdev) 
		goto err_clk_disable;



	for (i = 0; i < ddata->dma_channels; i++) {

		char name[12];



		if (chan_reserved & BIT(i))

			continue;



		chan = &ddata->chans[i];

		snprintf(name, sizeof(name), "dma%dchan%d", ddata->dma_dev.dev_id, chan->id);



		chan->vchan.desc_free = stm32_dma3_chan_vdesc_free;

		vchan_init(&chan->vchan, dma_dev);



		ret = dma_async_device_channel_register(&ddata->dma_dev, &chan->vchan.chan, name);

		if (ret) {

			dev_err_probe(&pdev->dev, ret, "Failed to register channel %s\n", name);

			goto err_clk_disable;

		}



		ret = platform_get_irq(pdev, i);

		if (ret < 0)

			goto err_clk_disable;



		chan = &ddata->chans[i];

		chan->irq = ret;



		ret = devm_request_irq(&pdev->dev, chan->irq, stm32_dma3_chan_irq, 0,