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: Amelie Delaunay <amelie.delaunay@xxxxxxxxxxx>
---
drivers/dma/stm32/stm32-dma3.c | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)
diff --git a/drivers/dma/stm32/stm32-dma3.c b/drivers/dma/stm32/stm32-dma3.c
index b0e917d52f59..43a0f02a74e0 100644
--- a/drivers/dma/stm32/stm32-dma3.c
+++ b/drivers/dma/stm32/stm32-dma3.c
@@ -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,
--
2.25.1
