Messages in this thread | | | Date | Sun, 5 Aug 2012 12:02:25 +0200 | Subject | Re: [PATCH] gpio-ich: Share ownership of GPIO groups | From | Linus Walleij <> |
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On Mon, Jul 23, 2012 at 5:34 PM, Jean Delvare <khali@linux-fr.org> wrote:
> The ICH chips have their GPIO pins organized in 2 or 3 independent > groups of 32 GPIO pins. It can happen that the ACPI BIOS wants to make > use of pins in one group, preventing the OS to access these. This does > not prevent the OS from accessing the other group(s). > > This is the case for example on my Asus Z8NA-D6 board. The ACPI BIOS > wants to control GPIO 18 (group 1), while I (the OS) need to control > GPIO 52 and 53 (group 2) for SMBus multiplexing. > > So instead of checking for ACPI resource conflict on the whole I/O > range, check on a per-group basis, and consider it a success if at > least one of the groups is available for the OS to use. > > Signed-off-by: Jean Delvare <khali@linux-fr.org> > Cc: Peter Tyser <ptyser@xes-inc.com> > Cc: Aaron Sierra <asierra@xes-inc.com> > Cc: Grant Likely <grant.likely@secretlab.ca> > Cc: Samuel Ortiz <sameo@linux.intel.com> > --- > That's probably not the nicest code you've seen, but everything else I > could think of either couldn't work or was looking worse. If anyone can > think of a better approach, I'm all ears.
I'm not very good at Intel and SMBus so cannot really help either.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
I guess you're bringing this through Sam's tree.
Yours, Linus Walleij
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