dmaengine: at_hdmac: Drop locking in at_hdmac_alloc_chan_resources() (bbc58394) · Commits · 戴 / test

There is no need for locking in device_alloc_chan_resources(), the DMA core takes care of it by using a dma_list_mutex around the DMA devices. Signed-off-by:

Tudor Ambarus <tudor.ambarus@microchip.com> Acked-by:

Ludovic Desroches <ludovic.desroches@microchip.com> Link: https://lore.kernel.org/r/20200123140237.125799-2-tudor.ambarus@microchip.com Signed-off-by:

Vinod Koul <vkoul@kernel.org>

drivers/dma/at_hdmac.c

+1 −6

Original line number	Diff line number	Diff line
		@@ -1542,10 +1542,8 @@ static int atc_alloc_chan_resources(struct dma_chan *chan)
		struct at_dma *atdma = to_at_dma(chan->device);
		struct at_desc *desc;
		struct at_dma_slave *atslave;
		unsigned long flags;
		int i;
		u32 cfg;
		LIST_HEAD(tmp_list);

		dev_vdbg(chan2dev(chan), "alloc_chan_resources\n");

		@@ -1583,14 +1581,11 @@ static int atc_alloc_chan_resources(struct dma_chan *chan)
		"Only %d initial descriptors\n", i);
		break;
		}
		list_add_tail(&desc->desc_node, &tmp_list);
		list_add_tail(&desc->desc_node, &atchan->free_list);
		}

		spin_lock_irqsave(&atchan->lock, flags);
		atchan->descs_allocated = i;
		list_splice(&tmp_list, &atchan->free_list);
		dma_cookie_init(chan);
		spin_unlock_irqrestore(&atchan->lock, flags);

		/* channel parameters */
		channel_writel(atchan, CFG, cfg);

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