soc/tegra: pmc: move to using a restart handler

The pmc driver was previously exporting tegra_pmc_restart, which was
assigned to machine_desc.init_machine, taking precedence over the
restart handlers registered through register_restart_handler().

Signed-off-by: David Riley <davidriley@chromium.org>
[tomeu.vizoso@collabora.com: Rebased]
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
[treding@nvidia.com: minor cleanups]
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index c956395..cc119d1 100644
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -377,13 +377,10 @@
 }
 #endif /* CONFIG_SMP */
 
-/**
- * tegra_pmc_restart() - reboot the system
- * @mode: which mode to reboot in
- * @cmd: reboot command
- */
-void tegra_pmc_restart(enum reboot_mode mode, const char *cmd)
+static int tegra_pmc_restart_notify(struct notifier_block *this,
+				    unsigned long action, void *data)
 {
+	const char *cmd = data;
 	u32 value;
 
 	value = tegra_pmc_readl(PMC_SCRATCH0);
@@ -405,8 +402,15 @@
 	value = tegra_pmc_readl(0);
 	value |= 0x10;
 	tegra_pmc_writel(value, 0);
+
+	return NOTIFY_DONE;
 }
 
+static struct notifier_block tegra_pmc_restart_handler = {
+	.notifier_call = tegra_pmc_restart_notify,
+	.priority = 128,
+};
+
 static int powergate_show(struct seq_file *s, void *data)
 {
 	unsigned int i;
@@ -837,6 +841,13 @@
 			return err;
 	}
 
+	err = register_restart_handler(&tegra_pmc_restart_handler);
+	if (err) {
+		dev_err(&pdev->dev, "unable to register restart handler, %d\n",
+			err);
+		return err;
+	}
+
 	return 0;
 }