Re: [PATCH v2] iio: stm32-dac: Replace indio_dev->mlock with own device lock

From: Fabrice Gasnier
Date: Thu Aug 27 2020 - 05:03:56 EST


On 8/27/20 10:55 AM, Alexandru Ardelean wrote:
> On Wed, Aug 26, 2020 at 3:03 PM Alexandru Ardelean
> <alexandru.ardelean@xxxxxxxxxx> wrote:
>> From: Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx>
>>
>> As part of the general cleanup of indio_dev->mlock, this change replaces
>> it with a local lock. The lock protects against potential races when
>> reading the CR reg and then updating, so that the state of pm_runtime
>> is consistent between the two operations.
>>
>> Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@xxxxxxxxxx>
>> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
>> ---
> Forgot the changelog here.
> Apologies.
>
> Changelog v1 -> v2:
> * removed whitespace change for 'common' field
> * updated comment about the lock usage

Hi Alexandru,

Sorry if I missed it... is there an update on the comment :-) ?

Best Regards,
Fabrice
>
>> drivers/iio/dac/stm32-dac.c | 12 ++++++++----
>> 1 file changed, 8 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/iio/dac/stm32-dac.c b/drivers/iio/dac/stm32-dac.c
>> index 092c796fa3d9..7a8aed476850 100644
>> --- a/drivers/iio/dac/stm32-dac.c
>> +++ b/drivers/iio/dac/stm32-dac.c
>> @@ -26,9 +26,11 @@
>> /**
>> * struct stm32_dac - private data of DAC driver
>> * @common: reference to DAC common data
>> + * @lock: lock to protect the data buffer during regmap ops
>> */
>> struct stm32_dac {
>> struct stm32_dac_common *common;
>> + struct mutex lock;
>> };