2020-05-14 09:03:15

by Sergiu Cuciurean

Subject: [PATCH] iio: dac: ad5446: Replace indio_dev->mlock with own device lock

As part of the general cleanup of indio_dev->mlock, this change replaces
it with a local lock on the device's state structure.

Signed-off-by: Sergiu Cuciurean <[email protected]>
---
drivers/iio/dac/ad5446.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/dac/ad5446.c b/drivers/iio/dac/ad5446.c
index 9884e29b19b7..8f8afc8999bc 100644
--- a/drivers/iio/dac/ad5446.c
+++ b/drivers/iio/dac/ad5446.c
@@ -33,6 +33,7 @@
* @chip_info: chip model specific constants, available modes etc
* @reg: supply regulator
* @vref_mv: actual reference voltage used
+ * @lock lock to protect the data buffer during write ops
*/

struct ad5446_state {
@@ -43,6 +44,7 @@ struct ad5446_state {
unsigned cached_val;
unsigned pwr_down_mode;
unsigned pwr_down;
+ struct mutex lock;
};

/**
@@ -112,7 +114,7 @@ static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
if (ret)
return ret;

- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
st->pwr_down = powerdown;

if (st->pwr_down) {
@@ -123,7 +125,7 @@ static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
}

ret = st->chip_info->write(st, val);
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);

return ret ? ret : len;
}
@@ -197,11 +199,11 @@ static int ad5446_write_raw(struct iio_dev *indio_dev,
return -EINVAL;

val <<= chan->scan_type.shift;
- mutex_lock(&indio_dev->mlock);
+ mutex_lock(&st->lock);
st->cached_val = val;
if (!st->pwr_down)
ret = st->chip_info->write(st, val);
- mutex_unlock(&indio_dev->mlock);
+ mutex_unlock(&st->lock);
break;
default:
ret = -EINVAL;
@@ -256,6 +258,8 @@ static int ad5446_probe(struct device *dev, const char *name,
indio_dev->channels = &st->chip_info->channel;
indio_dev->num_channels = 1;

+ mutex_init(&st->lock);
+
st->pwr_down_mode = MODE_PWRDWN_1k;

if (st->chip_info->int_vref_mv)
--
2.17.1

2020-05-16 15:16:44

by Jonathan Cameron

Subject: Re: [PATCH] iio: dac: ad5446: Replace indio_dev->mlock with own device lock

On Thu, 14 May 2020 12:00:42 +0300
Sergiu Cuciurean <[email protected]> wrote:

> As part of the general cleanup of indio_dev->mlock, this change replaces
> it with a local lock on the device's state structure.
>
> Signed-off-by: Sergiu Cuciurean <[email protected]>
Applied to the togreg branch of iio.git and pushed out as testing
for the autobuilders to play with it.

Thanks,

Jonathan

> ---
> drivers/iio/dac/ad5446.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iio/dac/ad5446.c b/drivers/iio/dac/ad5446.c
> index 9884e29b19b7..8f8afc8999bc 100644
> --- a/drivers/iio/dac/ad5446.c
> +++ b/drivers/iio/dac/ad5446.c
> @@ -33,6 +33,7 @@
> * @chip_info: chip model specific constants, available modes etc
> * @reg: supply regulator
> * @vref_mv: actual reference voltage used
> + * @lock lock to protect the data buffer during write ops
> */
>
> struct ad5446_state {
> @@ -43,6 +44,7 @@ struct ad5446_state {
> unsigned cached_val;
> unsigned pwr_down_mode;
> unsigned pwr_down;
> + struct mutex lock;
> };
>
> /**
> @@ -112,7 +114,7 @@ static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
> if (ret)
> return ret;
>
> - mutex_lock(&indio_dev->mlock);
> + mutex_lock(&st->lock);
> st->pwr_down = powerdown;
>
> if (st->pwr_down) {
> @@ -123,7 +125,7 @@ static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
> }
>
> ret = st->chip_info->write(st, val);
> - mutex_unlock(&indio_dev->mlock);
> + mutex_unlock(&st->lock);
>
> return ret ? ret : len;
> }
> @@ -197,11 +199,11 @@ static int ad5446_write_raw(struct iio_dev *indio_dev,
> return -EINVAL;
>
> val <<= chan->scan_type.shift;
> - mutex_lock(&indio_dev->mlock);
> + mutex_lock(&st->lock);
> st->cached_val = val;
> if (!st->pwr_down)
> ret = st->chip_info->write(st, val);
> - mutex_unlock(&indio_dev->mlock);
> + mutex_unlock(&st->lock);
> break;
> default:
> ret = -EINVAL;
> @@ -256,6 +258,8 @@ static int ad5446_probe(struct device *dev, const char *name,
> indio_dev->channels = &st->chip_info->channel;
> indio_dev->num_channels = 1;
>
> + mutex_init(&st->lock);
> +
> st->pwr_down_mode = MODE_PWRDWN_1k;
>
> if (st->chip_info->int_vref_mv)