On Sat, 02 May 2015, Laurent Pinchart wrote:
> Hi Nicholas,
>
> Thank you for the patch.
>
> On Friday 01 May 2015 16:16:01 Nicholas Mc Guire wrote:
> > wait_for_completion_timeout() returns unsigned long not int so the check
> > for <= should be == and the type unsigned long. This fixes up the return
> > value handling and returns -ETIMEDOUT on timeout rather than 0 and 1 on
> > on success rather than a more or less random remaining number of jiffies.
> >
> > Signed-off-by: Nicholas Mc Guire <hof...@osadl.org>
> > ---
> >
> > call sites:
> > read_fiforeg,write_ec_fiforeg assume > 0 == success
> > and the comment in flctl_dma_fifo0_transfe states
> > /* ret > 0 is success */
> > return ret;
> > since it is only checking for > 0 in the call-sites
> > returning -ETIMEDOUT should be fine.
> >
> > Patch was compile tested with ap325rxa_defconfig (implies
> > CONFIG_MTD_NAND_SH_FLCTL=y)
> >
> > Patch is against 4.1-rc1 (localversion-next is -next-20150501)
> >
> > drivers/mtd/nand/sh_flctl.c | 9 ++++++---
> > 1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/mtd/nand/sh_flctl.c b/drivers/mtd/nand/sh_flctl.c
> > index c3ce81c..4450864 100644
> > --- a/drivers/mtd/nand/sh_flctl.c
> > +++ b/drivers/mtd/nand/sh_flctl.c
> > @@ -354,6 +354,7 @@ static int flctl_dma_fifo0_transfer(struct sh_flctl
> > *flctl, unsigned long *buf, dma_cookie_t cookie = -EINVAL;
> > uint32_t reg;
> > int ret;
> > + unsigned long time_left;
> >
> > if (dir == DMA_FROM_DEVICE) {
> > chan = flctl->chan_fifo0_rx;
> > @@ -388,14 +389,16 @@ 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;
> > + } else
> > + ret = 1; /* completion succeeded */
>
> I'd go one step further and make this function return < 0 on error and 0 on
> success, like usually done through the kernel API. You could then simplify
> the
> code using something like
>
> if (!wait_for_completion_timeout(&flctl->dma_complete,
> msecs_to_jiffies(3000))) {
> dmaengine_terminate_all(chan);
> dev_err(&flctl->pdev->dev, "wait_for_completion_timeout\n");
> ret = -ETIMEDOUT;
> }
>
> (pre-initializing ret to 0)
>
> >
> > out:
> > reg = readl(FLINTDMACR(flctl));
>
ok - given that this needs some fixup anyway due to
not properly reading dmaengine_submit() - I'll fix
things up and re-submit.
thx!
hofrat
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
