Messages in this thread | | | Date | Tue, 18 Dec 2012 07:51:02 +0100 | From | Wolfgang Grandegger <> | Subject | Re: [PATCH RESEND 0/6 v10] gpio: Add block GPIO |
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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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