mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2026-10-28 20:03:05 +00:00
94227b9c88
Add a new driver for the power-, wake- and reset-source functionality of the Bay Trail (BYT) version of the Crystal Cove PMIC. The main functionality here is detecting which power-sources (USB / DC in / battery) are active. This is normally exposed to userspace as a power_supply class charger device with an online sysfs attribute. But if a charger is online or not is already exposed on BYT-CRC devices through either an ACPI AC power_supply device, or through a native driver for the battery charger chip (e.g. a BQ24292i). So instead of adding duplicate info under the power_supply class this driver exports the info through debugfs and likewise adds debugfs files for the reset- and wake-source info / registers. Despite this driver only exporting debugfs bits it is still useful to have this driver because it clears the wake- and reset-source registers after reading them. Not clearing these can have undesirable side-effects. Specifically if the WAKESRC register contains 0x01 (wake by powerbutton) on reboot then the firmware on some tablets turns the reboot into a poweroff. I guess this may be necessary to make long power-presses turn into a poweroff somehow? Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230303221928.285477-1-hdegoede@redhat.com
62 lines
2.2 KiB
62 lines
2.2 KiB