[PATCH 2/3] iio: qcom-spmi-iadc: cleanup wait_for_completion return handling

From: Nicholas Mc Guire
Date: Mon Feb 02 2015 - 03:41:28 EST


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 <hofrat@xxxxxxxxx>
---

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 */
--
1.7.10.4

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