[PATCH] collie: don't read GPSR

[Lothar Waßmann]

Hi,

Dmitry Eremin-Solenikov writes:
> On StrongARM GPSR is write-only according to docs, so don't read from
> it. Just set the required GPIO.
> 
Anyway GPSR (and GPCR) is a bit oriented register that allows
asserting individual bits without the need for read-modify-write
cycles, making the access inherently multithread safe. Using
read-modify-write on this register is contrary to the HW design.

A quick grep of the kernel source shows another abuse like this in
drivers/video/sa1100fb.c:             GPSR |= SHANNON_GPIO_DISP_EN;
drivers/video/sa1100fb.c:             GPCR |= SHANNON_GPIO_DISP_EN;


Lothar Waßmann
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