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. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
