Re: [PATCH] mtd: spi-nor: cadence-quadspi: make return type fit wait_for_completion_timeout

Nicholas Mc Guire
2018-07-27T05:23:48Z

On Thu, Jul 26, 2018 at 10:09:28PM +0200, Boris Brezillon wrote:
> On Wed, 25 Jul 2018 06:31:37 +0000
> Nicholas Mc Guire <der.herr@hofr.at> wrote:
>
> > On Tue, Jul 24, 2018 at 10:46:26PM +0200, Boris Brezillon wrote:
> > > On Sat, 21 Jul 2018 18:08:13 +0200
> > > Nicholas Mc Guire <hofrat@osadl.org> wrote:
> > >
> > > > wait_for_completion_timeout returns an unsigned long not int. declare a
> > > > suitably type timeout and fix up assignment and check.
> > > >
> > > > Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
> > > > Reported-by: Vignesh R <vigneshr@ti.com>
> > > > Fixes: 140623410536 ("mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller")
> > >
> > > If you don't mind, I'd like to squash all wait_for_completion_timeout()
> > > fixes into a single commit.
> > >
> > makes sense - no objections to that at all.
>
>
> I also dropped the timeout vars and checked the return of
> wait_for_completion_timeout() directly + removed the Fixes tag since
> it's no longer possible to attach the fix to a single commit and also,
> I'm sure the bug really existed (no overflow possible since the timeout
> values are small enough to fit in a signed int).
>
> Here is the resulting patch. Let me know if you're okay with this version.
>

looks good to me - quit a bit simpler than what I did - thanks !

thx!
hofrat

> Thanks,
>
> Boris
>
> --->8---
> From 69edac4ef4d1c8dac519b6d12afd4097ce72a54e Mon Sep 17 00:00:00 2001
> From: Nicholas Mc Guire <hofrat@osadl.org>
> Date: Sat, 21 Jul 2018 16:21:51 +0200
> Subject: [PATCH] mtd: spi-nor: cadence-quadspi: fix timeout handling
>
> wait_for_completion_timeout returns an unsigned long not an int, so
> let's check its return value directly instead of storing it in ret,
> and avoid checking for negative values since this cannot happen.
>
> Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
> Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
> ---
> drivers/mtd/spi-nor/cadence-quadspi.c | 20 ++++++++------------
> 1 file changed, 8 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c
> index c3f7aaa5d18f..7a19dae717fa 100644
> --- a/drivers/mtd/spi-nor/cadence-quadspi.c
> +++ b/drivers/mtd/spi-nor/cadence-quadspi.c
> @@ -525,15 +525,14 @@ static int cqspi_indirect_read_execute(struct spi_nor *nor, u8 *rxbuf,
> reg_base + CQSPI_REG_INDIRECTRD);
>
> while (remaining > 0) {
> - ret = wait_for_completion_timeout(&cqspi->transfer_complete,
> - msecs_to_jiffies
> - (CQSPI_READ_TIMEOUT_MS));
> + if (!wait_for_completion_timeout(&cqspi->transfer_complete,
> + msecs_to_jiffies(CQSPI_READ_TIMEOUT_MS)))
> + ret = -ETIMEDOUT;
>
> bytes_to_read = cqspi_get_rd_sram_level(cqspi);
>
> - if (!ret && bytes_to_read == 0) {
> + if (ret && bytes_to_read == 0) {
> dev_err(nor->dev, "Indirect read timeout, no bytes\n");
> - ret = -ETIMEDOUT;
> goto failrd;
> }
>
> @@ -649,10 +648,8 @@ static int cqspi_indirect_write_execute(struct spi_nor *nor, loff_t to_addr,
> iowrite32_rep(cqspi->ahb_base, txbuf,
> DIV_ROUND_UP(write_bytes, 4));
>
> - ret = wait_for_completion_timeout(&cqspi->transfer_complete,
> - msecs_to_jiffies
> - (CQSPI_TIMEOUT_MS));
> - if (!ret) {
> + if (!wait_for_completion_timeout(&cqspi->transfer_complete,
> + msecs_to_jiffies(CQSPI_TIMEOUT_MS))) {
> dev_err(nor->dev, "Indirect write timeout\n");
> ret = -ETIMEDOUT;
> goto failwr;
> @@ -986,9 +983,8 @@ static int cqspi_direct_read_execute(struct spi_nor *nor, u_char *buf,
> }
>
> dma_async_issue_pending(cqspi->rx_chan);
> - ret = wait_for_completion_timeout(&cqspi->rx_dma_complete,
> - msecs_to_jiffies(len));
> - if (ret <= 0) {
> + if (!wait_for_completion_timeout(&cqspi->rx_dma_complete,
> + msecs_to_jiffies(len))) {
> dmaengine_terminate_sync(cqspi->rx_chan);
> dev_err(nor->dev, "DMA wait_for_completion_timeout\n");
> ret = -ETIMEDOUT;