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Message-id: <1398850015-17761-4-git-send-email-ch.naveen@samsung.com>
Date: Wed, 30 Apr 2014 14:56:53 +0530
From: Naveen Krishna Chatradhi <ch.naveen@...sung.com>
To: linux-iio@...r.kernel.org
Cc: linux-kernel@...r.kernel.org, linux-samsung-soc@...r.kernel.org,
dianders@...omium.org, gregkh@...uxfoundation.org,
naveenkrishna.ch@...il.com, lars@...afoo.de, cpgs@...sung.com,
grundler@...omium.org, t.figa@...sung.com
Subject: [PATCH 3/5 v3] iio: exynos_adc: reduce timeout and use
wait_for_completion_timeout
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()
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@...sung.com>
Reviewed-by: Doug Anderson <dianders@...omium.org>
---
Changes since v2:
None
Changes since v1:
None
v0:
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 ff98c5d..939aaf7 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
--
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