ADC module on Exynos5 SoCs runs at 600KSPS. At this conversion rate,
waiting for 1000 msecs is wasteful (incase of h/w failure).

Hence, reduce the time out to 100msecs and use
wait_for_completion_timeout() instead of
wait_for_completion_interruptible_timeout()

Also, handle the return values in exynos_raw_read() call.

Change-Id: Icb8cade162094b2777c9f3c77120635deef5947c
Signed-off-by: Naveen Krishna Chatradhi <ch.nav...@samsung.com>
---
This change is a part of the patch reviewd at https://lkml.org/lkml/2013/11/5/92

 drivers/iio/adc/exynos_adc.c |   18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index a2b8b1a..4d2467a 100644
--- a/drivers/iio/adc/exynos_adc.c
+++ b/drivers/iio/adc/exynos_adc.c
@@ -82,7 +82,7 @@ enum adc_version {
 #define ADC_CON_EN_START       (1u << 0)
 #define ADC_DATX_MASK          0xFFF
 
-#define EXYNOS_ADC_TIMEOUT     (msecs_to_jiffies(1000))
+#define EXYNOS_ADC_TIMEOUT     (msecs_to_jiffies(100))
 
 struct exynos_adc {
        void __iomem            *regs;
@@ -121,6 +121,7 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
        struct exynos_adc *info = iio_priv(indio_dev);
        unsigned long timeout;
        u32 con1, con2;
+       int ret;
 
        if (mask != IIO_CHAN_INFO_RAW)
                return -EINVAL;
@@ -145,16 +146,19 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
                                ADC_V1_CON(info->regs));
        }
 
-       timeout = wait_for_completion_interruptible_timeout
+       timeout = wait_for_completion_timeout
                        (&info->completion, EXYNOS_ADC_TIMEOUT);
-       *val = info->value;
+       if (timeout == 0) {
+               ret = -ETIMEDOUT;
+       } else {
+               *val = info->value;
+               *val2 = 0;
+               ret = IIO_VAL_INT;
+       }
 
        mutex_unlock(&indio_dev->mlock);
 
-       if (timeout == 0)
-               return -ETIMEDOUT;
-
-       return IIO_VAL_INT;
+       return ret;
 }
 
 static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
-- 
1.7.9.5

--
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/

Reply via email to