soc/tegra: pmc: Restrict power-off handler to Nexus 7

The Tegra PMC power-off handler exists solely to reboot the Nexus 7 into
a special bootloader mode when a USB cable is connected, so that the
bootloader can display battery status instead of powering off. There is
no reason to register it on any other Tegra board.

Guard the registration behind of_machine_is_compatible("asus,grouper")
and rename the handler to tegra_pmc_grouper_power_off_handler to make
its scope explicit. The of_machine_is_compatible() check inside the
handler itself is now redundant and is removed.

This also avoids occupying SYS_OFF_PRIO_FIRMWARE on boards that have
other handlers at that priority level.

Assisted-by: Claude:claude-sonnet-4-6
Signed-off-by: Diogo Ivo <diogo.ivo@tecnico.ulisboa.pt>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index d4edf701a40f1bd941c38f3fce508eb1b3bda6cb..873edc3e7a2280b4a47e5c0b42c317f705ea5584 100644 (file)
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -1207,7 +1207,7 @@ static int tegra_pmc_restart_handler(struct sys_off_data *data)
        return NOTIFY_DONE;
 }
 
-static int tegra_pmc_power_off_handler(struct sys_off_data *data)
+static int tegra_pmc_grouper_power_off_handler(struct sys_off_data *data)
 {
        struct tegra_pmc *pmc = data->cb_data;
 
@@ -1215,8 +1215,7 @@ static int tegra_pmc_power_off_handler(struct sys_off_data *data)
         * Reboot Nexus 7 into special bootloader mode if USB cable is
         * connected in order to display battery status and power off.
         */
-       if (of_machine_is_compatible("asus,grouper") &&
-           power_supply_is_system_supplied()) {
+       if (power_supply_is_system_supplied()) {
                const u32 go_to_charger_mode = 0xa5a55a5a;
 
                tegra_pmc_writel(pmc, go_to_charger_mode, PMC_SCRATCH37);
@@ -3087,18 +3086,20 @@ static int tegra_pmc_probe(struct platform_device *pdev)
        }
 
        /*
-        * PMC should be primary power-off method if it soft-resets CPU,
-        * asking bootloader to shutdown hardware.
+        * PMC should be primary power-off method on Grouper if it soft-resets
+        * CPU, asking bootloader to shutdown hardware.
         */
-       err = devm_register_sys_off_handler(&pdev->dev,
-                                           SYS_OFF_MODE_POWER_OFF,
-                                           SYS_OFF_PRIO_FIRMWARE,
-                                           tegra_pmc_power_off_handler,
-                                           pmc);
-       if (err) {
-               dev_err(&pdev->dev, "failed to register sys-off handler: %d\n",
-                       err);
-               return err;
+       if (of_machine_is_compatible("asus,grouper")) {
+               err = devm_register_sys_off_handler(&pdev->dev,
+                                                   SYS_OFF_MODE_POWER_OFF,
+                                                   SYS_OFF_PRIO_FIRMWARE,
+                                                   tegra_pmc_grouper_power_off_handler,
+                                                   pmc);
+               if (err) {
+                       dev_err(&pdev->dev, "failed to register sys-off handler: %d\n",
+                               err);
+                       return err;
+               }
        }
 
        /*