Re: [PATCH v2 02/16] iio: adc: axp288_adc: do not use internal iio_dev lock

Jonathan Cameron
2022-10-09T11:56:10Z

On Tue, 4 Oct 2022 15:48:55 +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.
>
> While at it, properly include "mutex.h" for mutex related APIs.
>
> Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Applied with tiny tweak to drop the unrelated white space change.

Applied to the togreg branch of iio.git which is only pushed out
as testing until after a rebase on rc1.

Thanks,

Jonathan

> ---
> drivers/iio/adc/axp288_adc.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c
> index 580361bd9849..53781010f789 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);
> +
> info->irq = platform_get_irq(pdev, 0);
> if (info->irq < 0)
> return info->irq;
> @@ -289,6 +293,8 @@ static int axp288_adc_probe(struct platform_device *pdev)
> if (ret < 0)
> return ret;
>
> + mutex_init(&info->lock);
> +
> return devm_iio_device_register(&pdev->dev, indio_dev);
> }