On Fri, 23 Feb 2018 08:16:01 +0100, Hans de Goede wrote:
Hi,
On 22-02-18 14:20, Hans de Goede wrote:
On some boards setting power_save to a non 0 value leads to clicking / popping sounds when ever we enter/leave powersaving mode. Ideally we would figure out how to avoid these sounds, but that is not always feasible.
This commit adds a blacklist for devices where powersaving is known to cause problems and disables it on these devices.
Note I tried to put this blacklist in userspace first: https://github.com/systemd/systemd/pull/8128
But the systemd maintainers rightfully pointed out that it would be impossible to then later remove entries once we actually find a way to make power-saving work on listed boards without issues. Having this list in the kernel will allow removal of the blacklist entry in the same commit which fixes the clicks / plops.
The blacklist only applies to the default power_save module-option value, if a user explicitly sets the module-option then the blacklist is not used.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1525104 BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=198611 Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede hdegoede@redhat.com
This has been tested now, so this may be applied now, assuming people are happy with this version.
Let me know if you want me to re-submit as a non-RFC.
I applied it now, thanks.
Takashi