public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH v2] platform/chrome: cros_usbpd_notify: defer probe when parent EC driver isn't ready
@ 2025-10-07  0:40 Jameson Thies
  2025-10-07  9:49 ` Tzung-Bi Shih
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Jameson Thies @ 2025-10-07  0:40 UTC (permalink / raw)
  To: akuchynski, bleung, abhishekpandit, tzungbi
  Cc: jthies, chrome-platform, linux-kernel

The cros-usbpd-notify-acpi probe currently does not exit when it fails
to get a pointer to the ChromeOS EC device. It is expected behavior on
older devices, where GOOG0004 is not a parent of GOOG0003.

Update the cros-usbpd-notify-acpi probe to check for a GOOG0004 parent
fwnode. If the device has correct device hierarchy and fails to get an
EC device pointer, defer the probe function.

Signed-off-by: Jameson Thies <jthies@google.com>
---
 drivers/platform/chrome/cros_usbpd_notify.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/chrome/cros_usbpd_notify.c b/drivers/platform/chrome/cros_usbpd_notify.c
index 313d2bcd577b..c90174360004 100644
--- a/drivers/platform/chrome/cros_usbpd_notify.c
+++ b/drivers/platform/chrome/cros_usbpd_notify.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/fwnode.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/platform_data/cros_ec_proto.h>
@@ -15,6 +16,7 @@
 #define DRV_NAME "cros-usbpd-notify"
 #define DRV_NAME_PLAT_ACPI "cros-usbpd-notify-acpi"
 #define ACPI_DRV_NAME "GOOG0003"
+#define CREC_DRV_NAME "GOOG0004"
 
 static BLOCKING_NOTIFIER_HEAD(cros_usbpd_notifier_list);
 
@@ -98,8 +100,9 @@ static int cros_usbpd_notify_probe_acpi(struct platform_device *pdev)
 {
 	struct cros_usbpd_notify_data *pdnotify;
 	struct device *dev = &pdev->dev;
-	struct acpi_device *adev;
+	struct acpi_device *adev, *parent_adev;
 	struct cros_ec_device *ec_dev;
+	struct fwnode_handle *parent_fwnode;
 	acpi_status status;
 
 	adev = ACPI_COMPANION(dev);
@@ -114,8 +117,18 @@ static int cros_usbpd_notify_probe_acpi(struct platform_device *pdev)
 		/*
 		 * We continue even for older devices which don't have the
 		 * correct device heirarchy, namely, GOOG0003 is a child
-		 * of GOOG0004.
+		 * of GOOG0004. If GOOG0003 is a child of GOOG0004 and we
+		 * can't get a pointer to the Chrome EC device, defer the
+		 * probe function.
 		 */
+		parent_fwnode = fwnode_get_parent(dev->fwnode);
+		if (parent_fwnode) {
+			parent_adev = to_acpi_device_node(parent_fwnode);
+			if (parent_adev &&
+			    acpi_dev_hid_match(parent_adev, CREC_DRV_NAME)) {
+				return -EPROBE_DEFER;
+			}
+		}
 		dev_warn(dev, "Couldn't get Chrome EC device pointer.\n");
 	}
 

base-commit: 48633acccf38d706d7b368400647bb9db9caf1ae
-- 
2.51.0.618.g983fd99d29-goog


^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2025-10-13  2:57 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-10-07  0:40 [PATCH v2] platform/chrome: cros_usbpd_notify: defer probe when parent EC driver isn't ready Jameson Thies
2025-10-07  9:49 ` Tzung-Bi Shih
2025-10-07 18:35 ` Benson Leung
2025-10-13  2:57 ` Tzung-Bi Shih

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox