On 02/02/15 08:37, Nicholas Mc Guire wrote:
> This patch fixes two issues:
> * return type of wait_for_completion_timeout is unsigned long not int,
> rather than adding a dedicated variable the wait_for_completion_timeout
> is moved into the condition directly
> * the timeout of wait_for_completion_timeout is in jiffies but the value
> being passed was a unsigned long not converted to jiffies and thus was
> dependent on the HZ settings which is probably not what you want.
>
> Signed-off-by: Nicholas Mc Guire <hof...@osadl.org>
Ivan, need your Ack / Reviewed-by on this one.
Looks superficially fine to me, but as Nicholas has observed, hardware
knowledge / testing required!
J
> ---
>
> Note that the timeout value changed very significantly as wait was
> initially in the range of 2 milliseconds, so this converts to 1 jiffies
> for HZ < 1000 and 2 jiffies for HZ=1000 - thus the timeout value changed
> by 3 orders of magnitude. This needs a review by someone that knows the
> details of the hardware to judge if this change is ok - in any case the
> timeout passed should go through usecs_to_jiffies or msecs_to_jiffis and
> to ensure it is no longer HZ dependent.
>
> Patch was compile tested only for imx_v6_v7_defconfig + CONFIG_IIO=m
> CONFIG_COMPILE_TEST=y, CONFIG_SPMI=m, CONFIG_QCOM_SPMI_IADC=m
>
> Patch is against 3.19.0-rc6 -next-20150130
>
> drivers/iio/adc/qcom-spmi-iadc.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/qcom-spmi-iadc.c
> b/drivers/iio/adc/qcom-spmi-iadc.c
> index b9666f2..61fb88d 100644
> --- a/drivers/iio/adc/qcom-spmi-iadc.c
> +++ b/drivers/iio/adc/qcom-spmi-iadc.c
> @@ -296,8 +296,8 @@ static int iadc_do_conversion(struct iadc_chip *iadc, int
> chan, u16 *data)
> if (iadc->poll_eoc) {
> ret = iadc_poll_wait_eoc(iadc, wait);
> } else {
> - ret = wait_for_completion_timeout(&iadc->complete, wait);
> - if (!ret)
> + if (!wait_for_completion_timeout(&iadc->complete,
> + usecs_to_jiffies(wait)))
> ret = -ETIMEDOUT;
> else
> /* double check conversion status */
>
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