Re: [PATCH 03/15] iio: adc: axp288_adc: do not use internal iio_dev lock

Jonathan Cameron
2022-09-24T15:24:44Z

On Tue, 20 Sep 2022 13:28:09 +0200
Nuno Sá <nuno.sa@analog.com> wrote:

> The iio_device lock is only meant for internal use. Hence define a
> device local lock to protect against concurrent accesses.
>
> Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Looks good. Not sure how we missed cleaning this one up earlier
given how simple it is! Anyhow, given Andy's feedback I'll wait for v2
to pick this up.

> ---
> drivers/iio/adc/axp288_adc.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c
> index 580361bd9849..3bbb96156739 100644
> --- a/drivers/iio/adc/axp288_adc.c
> +++ b/drivers/iio/adc/axp288_adc.c
> @@ -9,6 +9,7 @@
>
> #include <linux/dmi.h>
> #include <linux/module.h>
> +#include <linux/mutex.h>
> #include <linux/kernel.h>
> #include <linux/device.h>
> #include <linux/regmap.h>
> @@ -50,6 +51,8 @@ enum axp288_adc_id {
> struct axp288_adc_info {
> int irq;
> struct regmap *regmap;
> + /* lock to protect against multiple access to the device */
> + struct mutex lock;
> bool ts_enabled;
> };
>
> @@ -161,7 +164,7 @@ static int axp288_adc_read_raw(struct iio_dev *indio_dev,
> int ret;
> struct axp288_adc_info *info = iio_priv(indio_dev);
>
> - mutex_lock(&indio_dev->mlock);
> + mutex_lock(&info->lock);
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> if (axp288_adc_set_ts(info, AXP288_ADC_TS_CURRENT_ON_ONDEMAND,
> @@ -178,7 +181,7 @@ static int axp288_adc_read_raw(struct iio_dev *indio_dev,
> default:
> ret = -EINVAL;
> }
> - mutex_unlock(&indio_dev->mlock);
> + mutex_unlock(&info->lock);
>
> return ret;
> }
> @@ -264,6 +267,7 @@ static int axp288_adc_probe(struct platform_device *pdev)
> return -ENOMEM;
>
> info = iio_priv(indio_dev);
> + mutex_init(&info->lock);
> info->irq = platform_get_irq(pdev, 0);
> if (info->irq < 0)
> return info->irq;