From ba2423633ba646e1df20e30cb3cf35495c16f173 Mon Sep 17 00:00:00 2001
From: Tudor Ambarus <tudor.ambarus@microchip.com>
Date: Tue, 25 Oct 2022 12:02:45 +0300
Subject: [PATCH] dmaengine: at_hdmac: Fix descriptor handling when issuing it to hardware
Git-commit: ba2423633ba646e1df20e30cb3cf35495c16f173
Patch-mainline: v6.1-rc5
References: git-fixes
As it was before, the descriptor was issued to the hardware without adding
it to the active (issued) list. This could result in a completion of other
descriptor, or/and in the descriptor never being completed.
Fixes: dc78baa2b90b ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com
Link: https://lore.kernel.org/r/20221025090306.297886-12-tudor.ambarus@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/dma/at_hdmac.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index b53a9fc15dd9..9e5a30396c1c 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -510,8 +510,11 @@ static void atc_advance_work(struct at_dma_chan *atchan)
/* advance work */
spin_lock_irqsave(&atchan->lock, flags);
- if (!list_empty(&atchan->active_list))
- atc_dostart(atchan, atc_first_active(atchan));
+ if (!list_empty(&atchan->active_list)) {
+ desc = atc_first_queued(atchan);
+ list_move_tail(&desc->desc_node, &atchan->active_list);
+ atc_dostart(atchan, desc);
+ }
spin_unlock_irqrestore(&atchan->lock, flags);
}
@@ -523,6 +526,7 @@ static void atc_advance_work(struct at_dma_chan *atchan)
static void atc_handle_error(struct at_dma_chan *atchan)
{
struct at_desc *bad_desc;
+ struct at_desc *desc;
struct at_desc *child;
unsigned long flags;
@@ -540,8 +544,11 @@ static void atc_handle_error(struct at_dma_chan *atchan)
list_splice_init(&atchan->queue, atchan->active_list.prev);
/* Try to restart the controller */
- if (!list_empty(&atchan->active_list))
- atc_dostart(atchan, atc_first_active(atchan));
+ if (!list_empty(&atchan->active_list)) {
+ desc = atc_first_queued(atchan);
+ list_move_tail(&desc->desc_node, &atchan->active_list);
+ atc_dostart(atchan, desc);
+ }
/*
* KERN_CRITICAL may seem harsh, but since this only happens
--
2.35.3