[PATCH] platform/chrome: cros_ec_lightbar: Check if ec supports suspend commands

Brady Norander
2025-10-23T23:44:56Z

The Chromebook Pixel 2013 (Link)'s ec does not support the lightbar manual suspend commands.
As a result, attempting to suspend the device fails and prints the following error:

cros-ec-lightbar cros-ec-lightbar.3.auto: PM: dpm_run_callback(): platform_pm_suspend returns -22
cros-ec-lightbar cros-ec-lightbar.3.auto: PM: failed to suspend: error -22
PM: Some devices failed to suspend, or early wake event detected

Check the return value of lb_manual_suspend_ctrl in cros_ec_lightbar_probe and disable manual
suspend control if an error is returned.

Signed-off-by: Brady Norander <bradynorander@gmail.com>

diff --git a/drivers/platform/chrome/cros_ec_lightbar.c b/drivers/platform/chrome/cros_ec_lightbar.c
index 87634f6921b7..1b7e4c4e18bc 100644
--- a/drivers/platform/chrome/cros_ec_lightbar.c
+++ b/drivers/platform/chrome/cros_ec_lightbar.c
@@ -30,6 +30,13 @@ static unsigned long lb_interval_jiffies = 50 * HZ / 1000;
*/
static bool userspace_control;

+/*
+ * Whether or not the lightbar supports the manual suspend commands.
+ * The Pixel 2013 (Link) does not while all other devices with a
+ * lightbar do.
+*/
+static bool has_manual_suspend;
+
static ssize_t interval_msec_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -550,7 +557,7 @@ static int cros_ec_lightbar_probe(struct platform_device *pd)
return -ENODEV;

/* Take control of the lightbar from the EC. */
- lb_manual_suspend_ctrl(ec_dev, 1);
+ has_manual_suspend = (lb_manual_suspend_ctrl(ec_dev, 1) >= 0);

ret = sysfs_create_group(&ec_dev->class_dev.kobj,
&cros_ec_lightbar_attr_group);
@@ -569,14 +576,15 @@ static void cros_ec_lightbar_remove(struct platform_device *pd)
&cros_ec_lightbar_attr_group);

/* Let the EC take over the lightbar again. */
- lb_manual_suspend_ctrl(ec_dev, 0);
+ if (has_manual_suspend)
+ lb_manual_suspend_ctrl(ec_dev, 0);
}

static int __maybe_unused cros_ec_lightbar_resume(struct device *dev)
{
struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);

- if (userspace_control)
+ if (userspace_control || !has_manual_suspend)
return 0;

return lb_send_empty_cmd(ec_dev, LIGHTBAR_CMD_RESUME);
@@ -586,7 +594,7 @@ static int __maybe_unused cros_ec_lightbar_suspend(struct device *dev)
{
struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);

- if (userspace_control)
+ if (userspace_control || !has_manual_suspend)
return 0;

return lb_send_empty_cmd(ec_dev, LIGHTBAR_CMD_SUSPEND);
--
2.51.0