[PATCH AUTOSEL 4.19 01/27] dmaengine: ste_dma40: fix unneeded variable warning

[PATCH AUTOSEL 4.19 01/27] dmaengine: ste_dma40: fix unneeded variable warning

[Sasha Levin]

From: Arnd Bergmann <arnd@arndb.de>

[ Upstream commit 5d6fb560729a5d5554e23db8d00eb57cd0021083 ]

clang-9 points out that there are two variables that depending on the
configuration may only be used in an ARRAY_SIZE() expression but not
referenced:

drivers/dma/ste_dma40.c:145:12: error: variable 'd40_backup_regs' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration]
static u32 d40_backup_regs[] = {
           ^
drivers/dma/ste_dma40.c:214:12: error: variable 'd40_backup_regs_chan' is not needed and will not be emitted [-Werror,-Wunneeded-internal-declaration]
static u32 d40_backup_regs_chan[] = {

Mark these __maybe_unused to shut up the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190712091357.744515-1-arnd@arndb.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/dma/ste_dma40.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index f4edfc56f34ef..3d55405c49cac 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -142,7 +142,7 @@ enum d40_events {
  * when the DMA hw is powered off.
  * TODO: Add save/restore of D40_DREG_GCC on dma40 v3 or later, if that works.
  */
-static u32 d40_backup_regs[] = {
+static __maybe_unused u32 d40_backup_regs[] = {
 	D40_DREG_LCPA,
 	D40_DREG_LCLA,
 	D40_DREG_PRMSE,
@@ -211,7 +211,7 @@ static u32 d40_backup_regs_v4b[] = {
 
 #define BACKUP_REGS_SZ_V4B ARRAY_SIZE(d40_backup_regs_v4b)
 
-static u32 d40_backup_regs_chan[] = {
+static __maybe_unused u32 d40_backup_regs_chan[] = {
 	D40_CHAN_REG_SSCFG,
 	D40_CHAN_REG_SSELT,
 	D40_CHAN_REG_SSPTR,
-- 
2.20.1

[PATCH AUTOSEL 4.19 15/27] dmaengine: stm32-mdma: Fix a possible null-pointer dereference in stm32_mdma_irq_handler()

[Sasha Levin]

From: Jia-Ju Bai <baijiaju1990@gmail.com>

[ Upstream commit 39c71a5b8212f4b502d9a630c6706ac723abd422 ]

In stm32_mdma_irq_handler(), chan is checked on line 1368.
When chan is NULL, it is still used on line 1369:
    dev_err(chan2dev(chan), "MDMA channel not initialized\n");

Thus, a possible null-pointer dereference may occur.

To fix this bug, "dev_dbg(mdma2dev(dmadev), ...)" is used instead.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Fixes: a4ffb13c8946 ("dmaengine: Add STM32 MDMA driver")
Link: https://lore.kernel.org/r/20190729020849.17971-1-baijiaju1990@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/dma/stm32-mdma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
index 06dd1725375e5..8c3c3e5b812a8 100644
--- a/drivers/dma/stm32-mdma.c
+++ b/drivers/dma/stm32-mdma.c
@@ -1376,7 +1376,7 @@ static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid)
 
 	chan = &dmadev->chan[id];
 	if (!chan) {
-		dev_err(chan2dev(chan), "MDMA channel not initialized\n");
+		dev_dbg(mdma2dev(dmadev), "MDMA channel not initialized\n");
 		goto exit;
 	}
 
-- 
2.20.1

[PATCH AUTOSEL 4.19 16/27] omap-dma/omap_vout_vrfb: fix off-by-one fi value

[Sasha Levin]

From: Hans Verkuil <hverkuil@xs4all.nl>

[ Upstream commit d555c34338cae844b207564c482e5a3fb089d25e ]

The OMAP 4 TRM specifies that when using double-index addressing
the address increases by the ES plus the EI value minus 1 within
a frame. When a full frame is transferred, the address increases
by the ES plus the frame index (FI) value minus 1.

The omap-dma code didn't account for the 'minus 1' in the FI register.
To get correct addressing, add 1 to the src_icg value.

This was found when testing a hacked version of the media m2m-deinterlace.c
driver on a Pandaboard.

The only other source that uses this feature is omap_vout_vrfb.c,
and that adds a + 1 when setting the dst_icg. This is a workaround
for the broken omap-dma.c behavior. So remove the workaround at the
same time that we fix omap-dma.c.

I tested the omap_vout driver with a Beagle XM board to check that
the '+ 1' in omap_vout_vrfb.c was indeed a workaround for the omap-dma
bug.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Link: https://lore.kernel.org/r/952e7f51-f208-9333-6f58-b7ed20d2ea0b@xs4all.nl
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/dma/ti/omap-dma.c                    | 4 ++--
 drivers/media/platform/omap/omap_vout_vrfb.c | 3 +--
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/ti/omap-dma.c b/drivers/dma/ti/omap-dma.c
index a4a931ddf6f69..aeb9c29e52554 100644
--- a/drivers/dma/ti/omap-dma.c
+++ b/drivers/dma/ti/omap-dma.c
@@ -1237,7 +1237,7 @@ static struct dma_async_tx_descriptor *omap_dma_prep_dma_interleaved(
 	if (src_icg) {
 		d->ccr |= CCR_SRC_AMODE_DBLIDX;
 		d->ei = 1;
-		d->fi = src_icg;
+		d->fi = src_icg + 1;
 	} else if (xt->src_inc) {
 		d->ccr |= CCR_SRC_AMODE_POSTINC;
 		d->fi = 0;
@@ -1252,7 +1252,7 @@ static struct dma_async_tx_descriptor *omap_dma_prep_dma_interleaved(
 	if (dst_icg) {
 		d->ccr |= CCR_DST_AMODE_DBLIDX;
 		sg->ei = 1;
-		sg->fi = dst_icg;
+		sg->fi = dst_icg + 1;
 	} else if (xt->dst_inc) {
 		d->ccr |= CCR_DST_AMODE_POSTINC;
 		sg->fi = 0;
diff --git a/drivers/media/platform/omap/omap_vout_vrfb.c b/drivers/media/platform/omap/omap_vout_vrfb.c
index 29e3f5da59c1f..11ec048929e80 100644
--- a/drivers/media/platform/omap/omap_vout_vrfb.c
+++ b/drivers/media/platform/omap/omap_vout_vrfb.c
@@ -253,8 +253,7 @@ int omap_vout_prepare_vrfb(struct omap_vout_device *vout,
 	 */
 
 	pixsize = vout->bpp * vout->vrfb_bpp;
-	dst_icg = ((MAX_PIXELS_PER_LINE * pixsize) -
-		  (vout->pix.width * vout->bpp)) + 1;
+	dst_icg = MAX_PIXELS_PER_LINE * pixsize - vout->pix.width * vout->bpp;
 
 	xt->src_start = vout->buf_phy_addr[vb->i];
 	xt->dst_start = vout->vrfb_context[vb->i].paddr[0];
-- 
2.20.1