Re: [PATCH] Make PNP IDs all uppercase

Kay Sievers
2009-01-21T17:30:11Z

On Wed, Jan 21, 2009 at 18:09, Bjorn Helgaas <bjorn.helgaas@hp.com> wrote:
> On Wednesday 21 January 2009 12:56:07 am Philipp Kohlbecher wrote:
>> Bjorn Helgaas wrote:

>> > Did you trip over an actual problem that is fixed by this patch? If
>> > so, can you give any more details?
>>
>> Yes. After a package update, hwclock stopped using the "--directisa"
>> switch and could not access the RTC anymore. My RTC is handled by
>> rtc-cmos, which is compiled as a module. However, udev did not load this
>> module, as the device's modalias "acpi:PNP0B00:" did not match any of
>> the module's aliasas, including "acpi*:PNP0b00:*". Thus, the system
>> clock was not set correctly at startup (my hardware clock is set to
>> local time). Changing the PNP IDs in drivers/rtc/rtc-cmos.c to use
>> uppercase hex digits solved that problem for me.
>
> Nice work debugging that problem! I would include that synopsis in
> the changelog, because it helps people who trip over the same problem
> and are looking for a solution, and it helps people who want to
> understand why the change was made.

We uppercase all acpi alias strings now, so that should be solved:
http://git.kernel.org/?p=linux/kernel/git/gregkh/patches.git;a=blob;f=driver-core.current/pnp-fix-broken-pnp-lowercasing-for-acpi-module-aliases.patch;hb=HEAD

Kay