[PATCH] usb: typec: ucsi: Fix busy loop on ASUS VivoBooks

["Christian A. Ehrhardt" <lk@c--e.de>]

If the busy indicator is set, all other fields in CCI should be
clear according to the spec. However, some UCSI implementations do
not follow this rule and report bogus data in CCI along with the
busy indicator. Ignore the contents of CCI if the busy indicator is
set.

If a command timeout is hit it is possible that the EVENT_PENDING
bit is cleared while connector work is still scheduled which can
cause the EVENT_PENDING bit to go out of sync with scheduled connector
work. Check and set the EVENT_PENDING bit on entry to
ucsi_handle_connector_change() to fix this.

Finally, the quirk for some ASUS zenbook models is required for
ASUS VivoBooks as well. Apply the quirk to these as well.

Reported-by: Anurag Bijea <icaliberdev@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219108
Bisected-by: Christian Heusel <christian@heusel.eu>
Tested-by: Anurag Bijea <icaliberdev@gmail.com>
Fixes: de52aca4d9d5 ("usb: typec: ucsi: Never send a lone connector change ack")
Cc: stable@vger.kernel.org
Signed-off-by: Christian A. Ehrhardt <lk@c--e.de>
---
 drivers/usb/typec/ucsi/ucsi.c      | 8 ++++++++
 drivers/usb/typec/ucsi/ucsi_acpi.c | 7 +++++++
 2 files changed, 15 insertions(+)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index 4039851551c1..540cb1d2822c 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -38,6 +38,10 @@
 
 void ucsi_notify_common(struct ucsi *ucsi, u32 cci)
 {
+	/* Ignore bogus data in CCI if busy indicator is set. */
+	if (cci & UCSI_CCI_BUSY)
+		return;
+
 	if (UCSI_CCI_CONNECTOR(cci))
 		ucsi_connector_change(ucsi, UCSI_CCI_CONNECTOR(cci));
 
@@ -1249,6 +1253,10 @@ static void ucsi_handle_connector_change(struct work_struct *work)
 
 	mutex_lock(&con->lock);
 
+	if (!test_and_set_bit(EVENT_PENDING, &ucsi->flags))
+		dev_err_once(ucsi->dev, "%s entered without EVENT_PENDING\n",
+			     __func__);
+
 	command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num);
 
 	ret = ucsi_send_command_common(ucsi, command, &con->status,
diff --git a/drivers/usb/typec/ucsi/ucsi_acpi.c b/drivers/usb/typec/ucsi/ucsi_acpi.c
index 7a5dff8d9cc6..aa586525ab4c 100644
--- a/drivers/usb/typec/ucsi/ucsi_acpi.c
+++ b/drivers/usb/typec/ucsi/ucsi_acpi.c
@@ -197,6 +197,13 @@ static const struct dmi_system_id ucsi_acpi_quirks[] = {
 		},
 		.driver_data = (void *)&ucsi_zenbook_ops,
 	},
+	{
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
+			DMI_MATCH(DMI_PRODUCT_NAME, "VivoBook_ASUSLaptop"),
+		},
+		.driver_data = (void *)&ucsi_zenbook_ops,
+	},
 	{
 		.matches = {
 			DMI_MATCH(DMI_SYS_VENDOR, "LG Electronics"),
-- 
2.43.0