[PATCH 02/10] dmaengine: at_hdmac: Drop locking in at_hdmac_alloc_chan_resources()

From: Tudor.Ambarus
Date: Thu Jan 23 2020 - 09:03:15 EST


From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>

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@xxxxxxxxxxxxx>
---
drivers/dma/at_hdmac.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index cad6dcd9cfb5..301bae45cf8d 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -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);
--
2.23.0