4.15-stable review patch. If anyone has any objections, please let me know.
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From: Hans de Goede hdegoede@redhat.com
[ Upstream commit 7d09995dcb0577b4a56aad7f2bb56f28604e8f1a ]
ACPI enumerated serdev-controllers do not have an ACPI companion, the ACPI companion belongs to the serdev-device child of the serdev-controller, not to the controller itself. This was causing serdev_uevent to always return -ENODEV when called on a serdev-controller leading to errors like these:
kernel: serial serial0: uevent: failed to send synthetic uevent
being logged. This commit modifies serdev_uevent to directly return 0 when called on an ACPI enumerated serdev-controller fixing this.
Note: I do not think that setting a modalias on a devicetree enumerated serdev-controller makes sense either. So perhaps the !dev->of_node part of the check can be dropped too, but I'm not entirely sure that doing this on devicetree too is correct.
Signed-off-by: Hans de Goede hdegoede@redhat.com Acked-by: Johan Hovold johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serdev/core.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/tty/serdev/core.c +++ b/drivers/tty/serdev/core.c @@ -54,6 +54,11 @@ static int serdev_uevent(struct device * int rc;
/* TODO: platform modalias */ + + /* ACPI enumerated controllers do not have a modalias */ + if (!dev->of_node && dev->type == &serdev_ctrl_type) + return 0; + rc = acpi_device_uevent_modalias(dev, env); if (rc != -ENODEV) return rc;