HID: intel-thc-hid: intel-quickspi: reset touch IC on system resume

On the Surface Pro 10 (Meteor Lake) the touchscreen stops working after a
suspend/resume cycle and only recovers after a reboot. The driver logs
"GET_DEVICE_INFO: recv failed: -11" on resume.

This platform suspends through s2idle: /sys/power/mem_sleep exposes
"[s2idle]" as the only state, there is no "deep"/S3 entry at all. The
touch IC nonetheless loses power across that s2idle suspend, the same
way it does across hibernation. quickspi_resume() only re-selects the
THC port, restores interrupts and DMA and sends a HIDSPI_ON command,
assuming the touch IC kept its power and state. When it has actually
lost power the HIDSPI_ON command is never acknowledged and the
descriptor read fails, leaving the touchscreen dead until the module is
reloaded.

quickspi_restore() already handles this for hibernation by
reconfiguring the THC SPI/LTR settings and running reset_tic() to
re-enumerate the device. Make quickspi_resume() do the same when the
device is not a wake source. A wake-enabled device keeps its power and
state across suspend, so it stays on the light restore path: resetting
it would discard a pending wake touch event and break wake-on-touch.

The non-wake path mirrors the existing quickspi_restore() sequence,
including enabling interrupts before reset_tic(), so it introduces no
new ordering relative to code already in the driver.

This change has been validated on a Surface Pro 10 running the
linux-surface kernel across multiple s2idle suspend/resume cycles; it
has not been tested on a mainline build.

Closes: https://github.com/linux-surface/linux-surface/issues/1799
Signed-off-by: Danny D. <d3z.the.dev@gmail.com>
Reviewed-by: Even Xu <even.xu@intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

0 files changed, 0 insertions, 0 deletions