From 62e79e38b257a59f1e3d8aff801ae8590e2e45b4 Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Wed, 29 Nov 2023 09:43:30 -0300 Subject: [PATCH] thermal/thermal_of: Allow rebooting after critical temp Currently, the default mechanism is to trigger a shutdown after the critical temperature is reached. In some embedded cases, such behavior does not suit well, as the board may be unattended in the field and rebooting may be a better approach. The bootloader may also check the temperature and only allow the boot to proceed when the temperature is below a certain threshold. Introduce support for allowing a reboot to be triggered after the critical temperature is reached. If the "critical-action" devicetree property is not found, fall back to the shutdown action to preserve the existing default behavior. If a custom ops->critical exists, then it takes preference over critical-actions. Tested on a i.MX8MM board with the following devicetree changes: thermal-zones { cpu-thermal { critical-action = "reboot"; }; }; Signed-off-by: Fabio Estevam Signed-off-by: Daniel Lezcano Link: https://lore.kernel.org/r/20231129124330.519423-4-festevam@gmail.com --- drivers/thermal/thermal_of.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c index 1e0655b63259..4d6c22e0ed85 100644 --- a/drivers/thermal/thermal_of.c +++ b/drivers/thermal/thermal_of.c @@ -475,6 +475,7 @@ static struct thermal_zone_device *thermal_of_zone_register(struct device_node * struct thermal_zone_params tzp = {}; struct thermal_zone_device_ops *of_ops; struct device_node *np; + const char *action; int delay, pdelay; int ntrips, mask; int ret; @@ -511,6 +512,11 @@ static struct thermal_zone_device *thermal_of_zone_register(struct device_node * mask = GENMASK_ULL((ntrips) - 1, 0); + ret = of_property_read_string(np, "critical-action", &action); + if (!ret) + if (!of_ops->critical && !strcasecmp(action, "reboot")) + of_ops->critical = thermal_zone_device_critical_reboot; + tz = thermal_zone_device_register_with_trips(np->name, trips, ntrips, mask, data, of_ops, &tzp, pdelay, delay);