[PATCH RESEND 0/6 v10] gpio: Add block GPIO

Wolfgang Grandegger wg at grandegger.com
Tue Dec 18 01:51:02 EST 2012


On 12/17/2012 10:33 PM, Roland Stigge wrote:
> On 17/12/12 20:47, Wolfgang Grandegger wrote:
>> On 12/17/2012 07:02 PM, Roland Stigge wrote:
>>> On 12/17/2012 06:37 PM, Wolfgang Grandegger wrote:
>>>> 	/* Do synchronous data output with a single write access */
>>>> 	__raw_writel(~mask, pio + PIO_OWDR);
>>>> 	__raw_writel(mask, pio + PIO_OWER);
>>>> 	__raw_writel(val, pio + PIO_ODSR);
>>>>
>>>> For caching we would need a storage. Not sure if it's worth compared to
>>>> a context switch into the kernel.
>>>
>>> Block GPIO is not only for you in userspace. ;-) You can also implement
>>> efficient n-bit bus I/O in kernel drivers, n-bit-banging. :-) So not
>>> always context switches involved.
>>
>> OK, what do you think about the following untested patch:
> 
> Looks good!
> 
> Why "untested"? ;-)

Because I didn't have a chance to test it yet. Will do tomorrow.

Wolfgang.




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