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

Zumeng Chen zumeng.chen at windriver.com
Wed Jun 13 05:03:55 EDT 2012


于 2012年06月13日 15:51, Igor Grinberg 写道:
> 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,
Yes, this is the case.
> I'd suggest you to implement
> the get_pendown_state() method in the board file.
it seems they are different way between gpio and
get_pendown_state, and gpio way is used for omap3
to drive ads7846, so I guess we may have to do like this.

Regards,
Zumeng
> 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");




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