xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mfd / platform: cros_ec_debugfs: Expose resume result via debugfs

Browse Source 
For ECs that support it, the EC returns the number of slp_s0
transitions and whether or not there was a timeout in the resume
response. Expose the last resume result to usermode via debugfs so
that usermode can detect and report S0ix timeouts.

Signed-off-by: Evan Green <evgreen@chromium.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
This commit is contained in:
Evan Green
2019-06-27 13:44:45 -07:00
committed by Enric Balletbo i Serra
parent c18e6ea101
commit 8c3166e17c
4 changed files with 31 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

22
Documentation/ABI/testing/debugfs-cros-ec
View File

@@ -32,3 +32,25 @@ Description:
is used for synchronizing the AP host time with the EC
log. An error is returned if the command is not supported
by the EC or there is a communication problem.
What: /sys/kernel/debug/<cros-ec-device>/last_resume_result
Date: June 2019
KernelVersion: 5.3
Description:
Some ECs have a feature where they will track transitions to
the (Intel) processor's SLP_S0 line, in order to detect cases
where a system failed to go into S0ix. When the system resumes,
an EC with this feature will return a summary of SLP_S0
transitions that occurred. The last_resume_result file returns
the most recent response from the AP's resume message to the EC.
The bottom 31 bits contain a count of the number of SLP_S0
transitions that occurred since the suspend message was
received. Bit 31 is set if the EC attempted to wake the
system due to a timeout when watching for SLP_S0 transitions.
Callers can use this to detect a wake from the EC due to
S0ix timeouts. The result will be zero if no suspend
transitions have been attempted, or the EC does not support
this feature.
Output will be in the format: "0x%08x\n".