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

Igor Grinberg grinberg at compulab.co.il
Wed Jun 13 03:51:26 EDT 2012


On 06/13/12 04:44, 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

Unless this concerns many boards/archs/platforms, I'd suggest you to implement
the get_pendown_state() method in the board file.
If more users will need this, it can be facilitated in the driver.
(and of course not with the ugly ifdefs...)

>  
>  	} else {
>  		dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");

-- 
Regards,
Igor.



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