[PATCH 5.10 059/129] mtd: rawnand: Fix return value check of wait_for_completion_timeout

Greg Kroah-Hartman
2022-05-04T17:01:45Z

From: Miaoqian Lin <linmq006@gmail.com>

[ Upstream commit 084c16ab423a8890121b902b405823bfec5b4365 ]

wait_for_completion_timeout() returns unsigned long not int.
It returns 0 if timed out, and positive if completed.
The check for <= 0 is ambiguous and should be == 0 here
indicating timeout which is the only error case.

Fixes: 83738d87e3a0 ("mtd: sh_flctl: Add DMA capabilty")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220412083435.29254-1-linmq006@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/mtd/nand/raw/sh_flctl.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/mtd/nand/raw/sh_flctl.c b/drivers/mtd/nand/raw/sh_flctl.c
index 13df4bdf792a..8f89e2d3d817 100644
--- a/drivers/mtd/nand/raw/sh_flctl.c
+++ b/drivers/mtd/nand/raw/sh_flctl.c
@@ -384,7 +384,8 @@ static int flctl_dma_fifo0_transfer(struct sh_flctl *flctl, unsigned long *buf,
dma_addr_t dma_addr;
dma_cookie_t cookie;
uint32_t reg;
- int ret;
+ int ret = 0;
+ unsigned long time_left;

if (dir == DMA_FROM_DEVICE) {
chan = flctl->chan_fifo0_rx;
@@ -425,13 +426,14 @@ static int flctl_dma_fifo0_transfer(struct sh_flctl *flctl, unsigned long *buf,
goto out;
}

- ret =
+ time_left =
wait_for_completion_timeout(&flctl->dma_complete,
msecs_to_jiffies(3000));

- if (ret <= 0) {
+ if (time_left == 0) {
dmaengine_terminate_all(chan);
dev_err(&flctl->pdev->dev, "wait_for_completion_timeout\n");
+ ret = -ETIMEDOUT;
}

out:
@@ -441,7 +443,7 @@ static int flctl_dma_fifo0_transfer(struct sh_flctl *flctl, unsigned long *buf,

dma_unmap_single(chan->device->dev, dma_addr, len, dir);

- /* ret > 0 is success */
+ /* ret == 0 is success */
return ret;
}

@@ -465,7 +467,7 @@ static void read_fiforeg(struct sh_flctl *flctl, int rlen, int offset)

/* initiate DMA transfer */
if (flctl->chan_fifo0_rx && rlen >= 32 &&
- flctl_dma_fifo0_transfer(flctl, buf, rlen, DMA_FROM_DEVICE) > 0)
+ !flctl_dma_fifo0_transfer(flctl, buf, rlen, DMA_FROM_DEVICE))
goto convert; /* DMA success */

/* do polling transfer */
@@ -524,7 +526,7 @@ static void write_ec_fiforeg(struct sh_flctl *flctl, int rlen,

/* initiate DMA transfer */
if (flctl->chan_fifo0_tx && rlen >= 32 &&
- flctl_dma_fifo0_transfer(flctl, buf, rlen, DMA_TO_DEVICE) > 0)
+ !flctl_dma_fifo0_transfer(flctl, buf, rlen, DMA_TO_DEVICE))
return; /* DMA success */

/* do polling transfer */
--
2.35.1