]> git.itanic.dy.fi Git - linux-stable/commit
mfd: intel-lpss: Remove D3cold delay
authorKai-Heng Feng <kai.heng.feng@canonical.com>
Fri, 5 Jul 2019 04:55:03 +0000 (12:55 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 7 Oct 2019 19:01:01 +0000 (21:01 +0200)
commit59610f8b04ef23b7c1f95309d32df6154f7c8671
treed8675e7d06aa9131ea31d07c6369844abaaf3689
parent764029c0aaa6c84fb2420cefb15eed7845b411fa
mfd: intel-lpss: Remove D3cold delay

[ Upstream commit 76380a607ba0b28627c9b4b55cd47a079a59624b ]

Goodix touchpad may drop its first couple input events when
i2c-designware-platdrv and intel-lpss it connects to took too long to
runtime resume from runtime suspended state.

This issue happens becuase the touchpad has a rather small buffer to
store up to 13 input events, so if the host doesn't read those events in
time (i.e. runtime resume takes too long), events are dropped from the
touchpad's buffer.

The bottleneck is D3cold delay it waits when transitioning from D3cold
to D0, hence remove the delay to make the resume faster. I've tested
some systems with intel-lpss and haven't seen any regression.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202683
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/mfd/intel-lpss-pci.c