From 217d03411df5197d7bf9f7ff0c60b2cedba53d33 Mon Sep 17 00:00:00 2001
From: Tao Huang <huangtao@rock-chips.com>
Date: Thu, 22 Sep 2022 20:59:20 +0800
Subject: [PATCH] power: reset: reboot-mode: Don't miss panic reboot mode

pre_restart will rewrite reboot mode with normal mode when panic.

Fixes: c0b196cd5b85 ("power: reset: reboot-mode: Register callback for kernel pre restart")
Signed-off-by: Tao Huang <huangtao@rock-chips.com>
Change-Id: I8ad03b8f699b9c1a544a46bbdb60d118381d8356
---
 drivers/power/reset/reboot-mode.c | 21 +++++++++++++++++++--
 include/linux/reboot-mode.h       |  1 +
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c
index feaaa80caa9f..b0bb534f241e 100644
--- a/drivers/power/reset/reboot-mode.c
+++ b/drivers/power/reset/reboot-mode.c
@@ -51,6 +51,8 @@ static int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
 	return magic;
 }
 
+static int last_magic;
+
 static void reboot_mode_write(struct reboot_mode_driver *reboot,
 			      const void *cmd)
 {
@@ -59,8 +61,10 @@ static void reboot_mode_write(struct reboot_mode_driver *reboot,
 	magic = get_reboot_mode_magic(reboot, cmd);
 	if (!magic)
 		magic = get_reboot_mode_magic(reboot, NULL);
-	if (magic)
+	if (magic) {
 		reboot->write(reboot, magic);
+		last_magic = magic;
+	}
 }
 
 static int reboot_mode_notify(struct notifier_block *this,
@@ -74,6 +78,18 @@ static int reboot_mode_notify(struct notifier_block *this,
 	return NOTIFY_DONE;
 }
 
+static int reboot_mode_pre_restart_notify(struct notifier_block *this,
+			      unsigned long mode, void *cmd)
+{
+	struct reboot_mode_driver *reboot;
+
+	reboot = container_of(this, struct reboot_mode_driver, pre_restart_notifier);
+	if (cmd || !last_magic)
+		reboot_mode_write(reboot, cmd);
+
+	return NOTIFY_DONE;
+}
+
 static int reboot_mode_panic_notify(struct notifier_block *this,
 				      unsigned long ev, void *ptr)
 {
@@ -151,9 +167,10 @@ int reboot_mode_register(struct reboot_mode_driver *reboot)
 
 	boot_mode_parse(reboot);
 	reboot->reboot_notifier.notifier_call = reboot_mode_notify;
+	reboot->pre_restart_notifier.notifier_call = reboot_mode_pre_restart_notify;
 	reboot->panic_notifier.notifier_call = reboot_mode_panic_notify;
 	register_reboot_notifier(&reboot->reboot_notifier);
-	register_pre_restart_handler(&reboot->reboot_notifier);
+	register_pre_restart_handler(&reboot->pre_restart_notifier);
 	atomic_notifier_chain_register(&panic_notifier_list,
 				       &reboot->panic_notifier);
 	ret = sysfs_create_file(kernel_kobj, &kobj_boot_mode.attr);
diff --git a/include/linux/reboot-mode.h b/include/linux/reboot-mode.h
index a7aa69d004c4..250147abb6f3 100644
--- a/include/linux/reboot-mode.h
+++ b/include/linux/reboot-mode.h
@@ -8,6 +8,7 @@ struct reboot_mode_driver {
 	int (*write)(struct reboot_mode_driver *reboot, unsigned int magic);
 	int (*read)(struct reboot_mode_driver *reboot);
 	struct notifier_block reboot_notifier;
+	struct notifier_block pre_restart_notifier;
 	struct notifier_block panic_notifier;
 };