[PATCH] spi: spi-ti-qspi: Fix return value handling of wait_for_completion_timeout

[PATCH] spi: spi-ti-qspi: Fix return value handling of wait_for_completion_timeout

[Miaoqian Lin]

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: 5720ec0a6d26 ("spi: spi-ti-qspi: Add DMA support for QSPI mmap read")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
---
 drivers/spi/spi-ti-qspi.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c
index e06aafe169e0..081da1fd3fd7 100644
--- a/drivers/spi/spi-ti-qspi.c
+++ b/drivers/spi/spi-ti-qspi.c
@@ -448,6 +448,7 @@ static int ti_qspi_dma_xfer(struct ti_qspi *qspi, dma_addr_t dma_dst,
 	enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
 	struct dma_async_tx_descriptor *tx;
 	int ret;
+	unsigned long time_left;
 
 	tx = dmaengine_prep_dma_memcpy(chan, dma_dst, dma_src, len, flags);
 	if (!tx) {
@@ -467,9 +468,9 @@ static int ti_qspi_dma_xfer(struct ti_qspi *qspi, dma_addr_t dma_dst,
 	}
 
 	dma_async_issue_pending(chan);
-	ret = wait_for_completion_timeout(&qspi->transfer_complete,
+	time_left = wait_for_completion_timeout(&qspi->transfer_complete,
 					  msecs_to_jiffies(len));
-	if (ret <= 0) {
+	if (time_left == 0) {
 		dmaengine_terminate_sync(chan);
 		dev_err(qspi->dev, "DMA wait_for_completion_timeout\n");
 		return -ETIMEDOUT;
-- 
2.17.1

Re: [PATCH] spi: spi-ti-qspi: Fix return value handling of wait_for_completion_timeout

[Mark Brown]

On Mon, 11 Apr 2022 11:10:33 +0000, Miaoqian Lin wrote:
> 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.
> 
> 

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: spi-ti-qspi: Fix return value handling of wait_for_completion_timeout
      commit: 8b1ea69a63eb62f97cef63e6d816b64ed84e8760

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark