[PATCH 4.11 40/78] iio: proximity: as3935: recalibrate RCO after resume

Greg Kroah-Hartman
2017-06-19T15:21:48Z

From: Matt Ranostay <matt.ranostay@konsulko.com>

commit 6272c0de13abf1480f701d38288f28a11b4301c4 upstream.

According to the datasheet the RCO must be recalibrated
on every power-on-reset. Also remove mutex locking in the
calibration function since callers other than the probe
function (which doesn't need it) will have a lock.

Fixes: 24ddb0e4bba4 ("iio: Add AS3935 lightning sensor support")
Cc: George McCollister <george.mccollister@gmail.com>
Signed-off-by: Matt Ranostay <matt.ranostay@konsulko.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/iio/proximity/as3935.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

--- a/drivers/iio/proximity/as3935.c
+++ b/drivers/iio/proximity/as3935.c
@@ -269,8 +269,6 @@ static irqreturn_t as3935_interrupt_hand

static void calibrate_as3935(struct as3935_state *st)
{
- mutex_lock(&st->lock);
-
/* mask disturber interrupt bit */
as3935_write(st, AS3935_INT, BIT(5));

@@ -280,8 +278,6 @@ static void calibrate_as3935(struct as39

mdelay(2);
as3935_write(st, AS3935_TUNE_CAP, (st->tune_cap / TUNE_CAP_DIV));
-
- mutex_unlock(&st->lock);
}

#ifdef CONFIG_PM_SLEEP
@@ -318,6 +314,8 @@ static int as3935_resume(struct device *
val &= ~AS3935_AFE_PWR_BIT;
ret = as3935_write(st, AS3935_AFE_GAIN, val);

+ calibrate_as3935(st);
+
err_resume:
mutex_unlock(&st->lock);