[PATCH 11/16] iio: adc: at91-sama5d2_adc: add locking parameter to at91_adc_read_info_raw()

From: Claudiu Beznea
Date: Thu Jun 09 2022 - 04:32:02 EST


Add a parameter to at91_adc_read_info_raw() to specify if st->lock mutex
need to be acquired. This prepares for the addition of temperature sensor
code which will re-use at91_adc_read_info_raw() function to read 2 voltages
for determining the real temperature.

Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
---
drivers/iio/adc/at91-sama5d2_adc.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 1283bcf4e682..8f8fef42de84 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -1583,7 +1583,8 @@ static irqreturn_t at91_adc_interrupt(int irq, void *private)
}

static int at91_adc_read_info_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan, int *val)
+ struct iio_chan_spec const *chan, int *val,
+ bool lock)
{
struct at91_adc_state *st = iio_priv(indio_dev);
int (*fn)(struct at91_adc_state *, int, u16 *) = NULL;
@@ -1602,13 +1603,15 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev,
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
- mutex_lock(&st->lock);
+ if (lock)
+ mutex_lock(&st->lock);

if (fn) {
ret = fn(st, chan->channel, &tmp_val);
*val = tmp_val;
ret = at91_adc_adjust_val_osr(st, val);
- mutex_unlock(&st->lock);
+ if (lock)
+ mutex_unlock(&st->lock);
iio_device_release_direct_mode(indio_dev);

return ret;
@@ -1644,7 +1647,8 @@ static int at91_adc_read_info_raw(struct iio_dev *indio_dev,
/* Needed to ACK the DRDY interruption */
at91_adc_readl(st, LCDR);

- mutex_unlock(&st->lock);
+ if (lock)
+ mutex_unlock(&st->lock);

iio_device_release_direct_mode(indio_dev);
return ret;
@@ -1658,7 +1662,8 @@ static int at91_adc_read_raw(struct iio_dev *indio_dev,

switch (mask) {
case IIO_CHAN_INFO_RAW:
- return at91_adc_read_info_raw(indio_dev, chan, val);
+ return at91_adc_read_info_raw(indio_dev, chan, val, true);
+
case IIO_CHAN_INFO_SCALE:
*val = st->vref_uv / 1000;
if (chan->differential)
--
2.34.1