Re: [PATCH] drm/bochs: add edid present check

From: Oleksandr Andrushchenko
Date: Wed Dec 19 2018 - 10:37:17 EST


On 12/19/18 5:21 PM, Gerd Hoffmann wrote:
Hi,

You could probably have a comment here explaining the magic below
(just like in the commit message to ease the task of understanding
while reading the code why 2 of 8 bytes of the EDID header is checked
and why it is all needed). Of course one can use git blame... Up to you
Makes sense.

+ if (readb(bochs->mmio + 0) != 0x00 ||
+ readb(bochs->mmio + 1) != 0xff)
bochs->mmio is defined as "void __iomemÂÂ *mmio;". Can we please avoid
void pointer arithmetic here?
Why is that a problem? gcc uses bytes when doing pointer arithmetic
with void pointers (even though it is undefined in the C standard),
and as far I know the linux kernel depends on that behavior anyway.

Also the driver already does it everywhere.
Ok then, just to be consistent with the rest of the driver.
cheers,
Gerd