From: Prashant Malani pmalani@chromium.org
commit ffebd90532728086007038986900426544e3df4e upstream.
The Type C ACPI device on older Chromebooks is not generated correctly (since their EC firmware doesn't support the new commands required). In such cases, the crafted ACPI device doesn't have an EC parent, and it is therefore not useful (it shouldn't be generated in the first place since the EC firmware doesn't support any of the Type C commands).
To handle devices which use these older firmware revisions, check for the parent EC device handle, and fail the probe if it's not found.
Fixes: fdc6b21e2444 ("platform/chrome: Add Type C connector class driver") Reported-by: Alyssa Ross hi@alyssa.is Reviewed-by: Tzung-Bi Shih tzungbi@google.com Signed-off-by: Prashant Malani pmalani@chromium.org Acked-by: Heikki Krogerus heikki.krogerus@linux.intel.com Reviewed-by: Alyssa Ross hi@alyssa.is Tested-by: Alyssa Ross hi@alyssa.is Link: https://lore.kernel.org/r/20220126190219.3095419-1-pmalani@chromium.org Signed-off-by: Benson Leung bleung@chromium.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/platform/chrome/cros_ec_typec.c | 6 ++++++ 1 file changed, 6 insertions(+)
--- a/drivers/platform/chrome/cros_ec_typec.c +++ b/drivers/platform/chrome/cros_ec_typec.c @@ -1075,7 +1075,13 @@ static int cros_typec_probe(struct platf return -ENOMEM;
typec->dev = dev; + typec->ec = dev_get_drvdata(pdev->dev.parent); + if (!typec->ec) { + dev_err(dev, "couldn't find parent EC device\n"); + return -ENODEV; + } + platform_set_drvdata(pdev, typec);
ret = cros_typec_get_cmd_version(typec);