From: Tudor Ambarus tudor.ambarus@microchip.com
stable inclusion from stable-v5.10.94 commit cd22e22e8eac2db210d7040757963fab6e1d8aa0 bugzilla: https://gitee.com/openeuler/kernel/issues/I531X9
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit bccfb96b59179d4f96cbbd1ddff8fac6d335eae4 upstream.
tx_submit is supposed to push the current transaction descriptor to a pending queue, waiting for issue_pending() to be called. issue_pending() must start the transfer, not tx_submit(), thus remove at_xdmac_start_xfer() from at_xdmac_tx_submit(). Clients of at_xdmac that assume that tx_submit() starts the transfer must be updated and call dma_async_issue_pending() if they miss to call it (one example is atmel_serial).
As the at_xdmac_start_xfer() is now called only from at_xdmac_advance_work() when !at_xdmac_chan_is_enabled(), the at_xdmac_chan_is_enabled() check is no longer needed in at_xdmac_start_xfer(), thus remove it.
Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver") Signed-off-by: Tudor Ambarus tudor.ambarus@microchip.com Link: https://lore.kernel.org/r/20211215110115.191749-2-tudor.ambarus@microchip.co... Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com --- drivers/dma/at_xdmac.c | 6 ------ 1 file changed, 6 deletions(-)
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 627ad74c879f..9cc8e701c47d 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -338,9 +338,6 @@ static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
- if (at_xdmac_chan_is_enabled(atchan)) - return; - /* Set transfer as active to not try to start it again. */ first->active_xfer = true;
@@ -430,9 +427,6 @@ static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx) dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n", __func__, atchan, desc); list_add_tail(&desc->xfer_node, &atchan->xfers_list); - if (list_is_singular(&atchan->xfers_list)) - at_xdmac_start_xfer(atchan, desc); - spin_unlock_irqrestore(&atchan->lock, irqflags); return cookie; }