Hi Javier,
On Wed, Sep 04, 2024 at 03:53:40PM +0200, Javier Carrasco wrote:
> On 04/09/2024 06:47, Dmitry Torokhov wrote:
> > Using guard notation makes the code more compact and error handling
> > more robust by ensuring that mutexes are released in all code paths
> > when control leaves critical section.
> >
> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> > ---
> > drivers/input/misc/iqs269a.c | 46 +++++++++++++-----------------------
> > 1 file changed, 16 insertions(+), 30 deletions(-)
> >
> > diff --git a/drivers/input/misc/iqs269a.c b/drivers/input/misc/iqs269a.c
> > index 843f8a3f3410..c34d847fa4af 100644
> > --- a/drivers/input/misc/iqs269a.c
> > +++ b/drivers/input/misc/iqs269a.c
>
> ...
>
> > @@ -453,9 +449,9 @@ static int iqs269_ati_base_get(struct iqs269_private *iqs269,
> > if (ch_num >= IQS269_NUM_CH)
> > return -EINVAL;
> >
> > - mutex_lock(&iqs269->lock);
> > + guard(mutex)(&iqs269->lock);
> > +
> > engine_b = be16_to_cpu(ch_reg[ch_num].engine_b);
>
> maybe scoped_guard() to keep the scope of the mutex as it used to be?
Thank you for looking over patches.
It is just a few computations extra, so I decided not to use
scoped_guard(). Note that original code was forced to release mutex
early to avoid having to unlock it in all switch branches.
>
> > - mutex_unlock(&iqs269->lock);
> >
> > switch (engine_b & IQS269_CHx_ENG_B_ATI_BASE_MASK) {
> > case IQS269_CHx_ENG_B_ATI_BASE_75:
> > @@ -491,7 +487,7 @@ static int iqs269_ati_target_set(struct iqs269_private *iqs269,
> > if (target > IQS269_CHx_ENG_B_ATI_TARGET_MAX)
> > return -EINVAL;
> >
> > - mutex_lock(&iqs269->lock);
> > + guard(mutex)(&iqs269->lock);
> >
> > engine_b = be16_to_cpu(ch_reg[ch_num].engine_b);
> >
> > @@ -501,8 +497,6 @@ static int iqs269_ati_target_set(struct iqs269_private *iqs269,
> > ch_reg[ch_num].engine_b = cpu_to_be16(engine_b);
> > iqs269->ati_current = false;
> >
> > - mutex_unlock(&iqs269->lock);
> > -
> > return 0;
> > }
> >
> > @@ -515,10 +509,9 @@ static int iqs269_ati_target_get(struct iqs269_private *iqs269,
> > if (ch_num >= IQS269_NUM_CH)
> > return -EINVAL;
> >
> > - mutex_lock(&iqs269->lock);
> > - engine_b = be16_to_cpu(ch_reg[ch_num].engine_b);
> > - mutex_unlock(&iqs269->lock);
> > + guard(mutex)(&iqs269->lock);
>
> same here?
>
> >
> > + engine_b = be16_to_cpu(ch_reg[ch_num].engine_b);
> > *target = (engine_b & IQS269_CHx_ENG_B_ATI_TARGET_MASK) * 32;
Same here, calculating the line above will take no time at all...
Thanks.
--
Dmitry
