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

From: Roland Stigge
Date: Mon Dec 17 2012 - 13:02:35 EST

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.

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