[RFC PATCH 3/4] usb: typec: ucsi: glink: Wake up the system on connector changes

[Vladyslav Tymoshchuk]

The UCSI notifications from PMIC GLINK report connector changes, a USB
cable being plugged in or out for one, and the completion of UCSI
commands. Enable wakeup on the device, so that pmic_glink reports them
as wakeup events: a cable change brings the system out of
suspend-to-idle and aborts a suspend in progress.

The completion of a command arrives only while the command is in
flight, so it can wake up the system only when a suspend has started
in the middle of one.

The same was proposed in [1], with the wakeup event reported from the
callback. pmic_glink reports it now, also for the notifications that
it holds back over system sleep.

Link: https://lore.kernel.org/all/20260722-ucsi_glink_wakeup-v2-1-b43dee56df24@xxxxxxxxxxxxxxxx/ [1]
Signed-off-by: Vladyslav Tymoshchuk <tvlad744@xxxxxxxxx>
---
I used an AI assistant (Claude) for the analysis and to draft this
patch and its description; I reviewed the result. The testing is
described in the cover letter.

 drivers/usb/typec/ucsi/ucsi_glink.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/usb/typec/ucsi/ucsi_glink.c b/drivers/usb/typec/ucsi/ucsi_glink.c
index 1db0c88d817e..b03320f5a6bb 100644
--- a/drivers/usb/typec/ucsi/ucsi_glink.c
+++ b/drivers/usb/typec/ucsi/ucsi_glink.c
@@ -7,6 +7,7 @@
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of_device.h>
+#include <linux/pm_wakeup.h>
 #include <linux/property.h>
 #include <linux/soc/qcom/pdr.h>
 #include <linux/usb/typec_mux.h>
@@ -455,6 +456,11 @@ static int pmic_glink_ucsi_probe(struct auxiliary_device *adev,
 		ucsi->port_orientation[port] = desc;
 	}
 
+	/* pmic_glink reports the notifications as wakeup events */
+	ret = devm_device_init_wakeup(dev);
+	if (ret)
+		return ret;
+
 	ucsi->client = devm_pmic_glink_client_alloc(dev, PMIC_GLINK_OWNER_USBC,
 						    pmic_glink_ucsi_callback,
 						    pmic_glink_ucsi_pdr_notify,
-- 
2.43.0