[PATCH V2 5/5] Input: ads7846: set proper debounce time in driver level

[Hiremath, Vaibhav]

On Thu, Jun 14, 2012 at 10:16:55, Zumeng Chen wrote:
> 于 2012年06月13日 20:18, Hiremath, Vaibhav 写道:
> > On Wed, Jun 13, 2012 at 07:14:10, Zumeng Chen wrote:
> >> From: Zumeng Chen<zumeng.chen at windriver.com>
> >>
> >> If we don't set proper debouce time for ads7846, then there are
> >> flooded interrupt counters of ads7846 responding to one time
> >> touch on screen, so the driver couldn't work well.
> >>
> >> And since most OMAP3 series boards pass NULL pointer of board_pdata
> >> to omap_ads7846_init, so it's more proper to set it in driver level
> >> after having gpio_request done.
> >>
> >> This patch has been validated on 3530evm.
> >>
> >> Signed-off-by: Zumeng Chen<zumeng.chen at windriver.com>
> >> Signed-off-by: Syed Mohammed Khasim<khasim at ti.com>
> >> ---
> >>   drivers/input/touchscreen/ads7846.c |    4 ++++
> >>   1 files changed, 4 insertions(+), 0 deletions(-)
> >>
> >> diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
> >> index f02028e..459ff29 100644
> >> --- a/drivers/input/touchscreen/ads7846.c
> >> +++ b/drivers/input/touchscreen/ads7846.c
> >> @@ -980,6 +980,10 @@ static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads784
> >>   		}
> >>
> >>   		ts->gpio_pendown = pdata->gpio_pendown;
> >> +#ifdef CONFIG_ARCH_OMAP3
> >> +		/* 310 means about 10 microsecond for omap3 */
> >> +		gpio_set_debounce(pdata->gpio_pendown, 310);
> >> +#endif
> >>
> > Zumeng,
> >
> > With my sign-off you are changing the original code, that too
> > without my sign-off and ack.
> > I wouldn't mind you to submit patches from my tree, but the expectation is
> > if you are changing the original code, it should be under your sign-off.
> Thanks, good to learn. I'll remove in next time.
> > Coming to the patch, #ifdef in driver is not recommended, and this 10msec
> > delay is specific to OMAP GPIO and driver should not be aware of this,
> > that's where you will find the original patch handling it in board file.
> According to the git blame of the board-omap3evm.c I think
> 96974a24 did a good thing to all the related codes for omap3
> boards. So I think we can call board and driver as BSP level :-)
> 
> If #ifdef in driver can save many codes, I guess it's deserved.
> 

No, not really.

In the same commit, the debounce time is already handled as an argument to 
the function omap_ads7846_init(), and that’s the way it should be.
So no need for #ifdefs in driver...

Thanks,
Vaibhav