The current locking is only preventing a triggered buffer Transfer and a
debugfs register access from happening at the same time. If a register
access happens during a buffered read, the action is doomed to fail anyway,
since we need to write a magic value to exit continuous read mode.
Remove locking from the trigger handler and use
iio_device_claim_direct_mode() instead in the register access function.
Signed-off-by: Jonathan Santos <Jonathan.Santos@xxxxxxxxxx>
---
v3 Changes:
* Also removed the mutex_init and lock variable.
v2 Changes:
* New patch in v2. It replaces the guard(mutex) patch.
---
drivers/iio/adc/ad7768-1.c | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)
diff --git a/drivers/iio/adc/ad7768-1.c b/drivers/iio/adc/ad7768-1.c
index 2e2d50ccb744..f5509a0a36ab 100644
--- a/drivers/iio/adc/ad7768-1.c
+++ b/drivers/iio/adc/ad7768-1.c
@@ -154,7 +154,6 @@ static const struct iio_chan_spec ad7768_channels[] = {
struct ad7768_state {
struct spi_device *spi;
struct regulator *vref;
- struct mutex lock;
struct clk *mclk;
unsigned int mclk_freq;
unsigned int samp_freq;
@@ -256,18 +255,21 @@ static int ad7768_reg_access(struct iio_dev *indio_dev,
struct ad7768_state *st = iio_priv(indio_dev);
int ret;
- mutex_lock(&st->lock);
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
if (readval) {
ret = ad7768_spi_reg_read(st, reg, 1);
if (ret < 0)
- goto err_unlock;
+ goto err_release;
*readval = ret;
ret = 0;
} else {
ret = ad7768_spi_reg_write(st, reg, writeval);
}
-err_unlock:
- mutex_unlock(&st->lock);
+err_release:
+ iio_device_release_direct_mode(indio_dev);
return ret;
}
@@ -471,18 +473,15 @@ static irqreturn_t ad7768_trigger_handler(int irq, void *p)
struct ad7768_state *st = iio_priv(indio_dev);
int ret;
- mutex_lock(&st->lock);
-
ret = spi_read(st->spi, &st->data.scan.chan, 3);
if (ret < 0)
- goto err_unlock;
+ goto out;
iio_push_to_buffers_with_timestamp(indio_dev, &st->data.scan,
iio_get_time_ns(indio_dev));
-err_unlock:
+out:
iio_trigger_notify_done(indio_dev->trig);
- mutex_unlock(&st->lock);
return IRQ_HANDLED;
}
@@ -611,8 +610,6 @@ static int ad7768_probe(struct spi_device *spi)
st->mclk_freq = clk_get_rate(st->mclk);
- mutex_init(&st->lock);
-
indio_dev->channels = ad7768_channels;
indio_dev->num_channels = ARRAY_SIZE(ad7768_channels);
indio_dev->name = spi_get_device_id(spi)->name;
--
2.34.1
