Re: [PATCH v5 1/7] Input: matrix_keypad - use fsleep for variable delay duration

[Dmitry Torokhov]

On Wed, Feb 19, 2025 at 05:34:49PM +0100, Manuel Traut wrote:
> On Fri, Jan 10, 2025 at 06:49:00AM +0100, Markus Burri wrote:
> > The delay is retrieved from a device-tree property, so the duration is
> > variable. fsleep guesses the best delay function based on duration.
> > 
> > see Documentation/timers/delay_sleep_functions.rst
> > 
> > Signed-off-by: Markus Burri <markus.burri@xxxxxx>
> 
> Reviewed-by: Manuel Traut <manuel.traut@xxxxxx> 

As I mentioned in other review activate_col() may be called in atomic
context where we can not sleep:

"activate_col() may be called in atomic context, and if fsleep() turns
into usleep_range() or msleep() we are going to have a bad time.

We should either stop using request_any_context_irq() or figure out if
interrupt handler can sleep or not and adjust behavior properly."

Unfortunately this was completely ignored.

> 
> > ---
> >  drivers/input/keyboard/matrix_keypad.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
> > index 2a3b3bf..5571d2e 100644
> > --- a/drivers/input/keyboard/matrix_keypad.c
> > +++ b/drivers/input/keyboard/matrix_keypad.c
> > @@ -68,7 +68,7 @@ static void activate_col(struct matrix_keypad *keypad, int col, bool on)
> >  	__activate_col(keypad, col, on);
> >  
> >  	if (on && keypad->col_scan_delay_us)
> > -		udelay(keypad->col_scan_delay_us);
> > +		fsleep(keypad->col_scan_delay_us);
> >  }
> >  
> >  static void activate_all_cols(struct matrix_keypad *keypad, bool on)
> > -- 
> > 2.39.5
> > 

Thanks.

-- 
Dmitry