[PATCH v3 30/47] x86: iris: Register with kernel power-off handler

[Guenter Roeck <linux@roeck-us.net>]

Register with kernel power-off handler instead of setting pm_power_off
directly. Register with high priority to reflect that the original code
overwrites existing power-off handlers.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v3:
- Replace poweroff in all newly introduced variables and in text
  with power_off or power-off as appropriate
- Replace POWEROFF_PRIORITY_xxx with POWER_OFF_PRIORITY_xxx
v2:
- Use define to specify poweroff handler priority
- Use devm_register_power_off_handler

 arch/x86/platform/iris/iris.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/arch/x86/platform/iris/iris.c b/arch/x86/platform/iris/iris.c
index 4d171e8..aac23db 100644
--- a/arch/x86/platform/iris/iris.c
+++ b/arch/x86/platform/iris/iris.c
@@ -23,6 +23,7 @@
 
 #include <linux/moduleparam.h>
 #include <linux/module.h>
+#include <linux/notifier.h>
 #include <linux/platform_device.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
@@ -47,15 +48,21 @@ static bool force;
 module_param(force, bool, 0);
 MODULE_PARM_DESC(force, "Set to one to force poweroff handler installation.");
 
-static void (*old_pm_power_off)(void);
-
-static void iris_power_off(void)
+static int iris_power_off(struct notifier_block *this, unsigned long unused1,
+			  void *unused2)
 {
 	outb(IRIS_GIO_PULSE, IRIS_GIO_OUTPUT);
 	msleep(850);
 	outb(IRIS_GIO_REST, IRIS_GIO_OUTPUT);
+
+	return NOTIFY_DONE;
 }
 
+static struct notifier_block iris_power_off_nb = {
+	.notifier_call = iris_power_off,
+	.priority = POWER_OFF_PRIORITY_HIGH,
+};
+
 /*
  * Before installing the power_off handler, try to make sure the OS is
  * running on an Iris.  Since Iris does not support DMI, this is done
@@ -65,20 +72,25 @@ static void iris_power_off(void)
 static int iris_probe(struct platform_device *pdev)
 {
 	unsigned char status = inb(IRIS_GIO_INPUT);
+	int ret;
+
 	if (status == IRIS_GIO_NODEV) {
 		printk(KERN_ERR "This machine does not seem to be an Iris. "
 			"Power off handler not installed.\n");
 		return -ENODEV;
 	}
-	old_pm_power_off = pm_power_off;
-	pm_power_off = &iris_power_off;
+
+	ret = devm_register_power_off_handler(&pdev->dev, &iris_power_off_nb);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to register power-off handler\n");
+		return ret;
+	}
 	printk(KERN_INFO "Iris power_off handler installed.\n");
 	return 0;
 }
 
 static int iris_remove(struct platform_device *pdev)
 {
-	pm_power_off = old_pm_power_off;
 	printk(KERN_INFO "Iris power_off handler uninstalled.\n");
 	return 0;
 }
-- 
1.9.1