[PATCH v3 20/47] mfd: rn5t618: Register power-off handler 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 low priority to reflect that the original code
only sets pm_power_off if it was not already set.

Cc: Beniamino Galvani <b.galvani@gmail.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:
- New patch

 drivers/mfd/rn5t618.c       | 32 ++++++++++++++++----------------
 include/linux/mfd/rn5t618.h |  2 ++
 2 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/drivers/mfd/rn5t618.c b/drivers/mfd/rn5t618.c
index 6668571..ed564d1 100644
--- a/drivers/mfd/rn5t618.c
+++ b/drivers/mfd/rn5t618.c
@@ -15,6 +15,8 @@
 #include <linux/mfd/core.h>
 #include <linux/mfd/rn5t618.h>
 #include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/pm.h>
 #include <linux/regmap.h>
 
 static const struct mfd_cell rn5t618_cells[] = {
@@ -47,16 +49,20 @@ static const struct regmap_config rn5t618_regmap_config = {
 	.cache_type	= REGCACHE_RBTREE,
 };
 
-static struct rn5t618 *rn5t618_pm_power_off;
-
-static void rn5t618_power_off(void)
+static int rn5t618_power_off(struct notifier_block *this,
+			     unsigned long unused1, void *unused2)
 {
+	struct rn5t618 *rn5t618 = container_of(this, struct rn5t618,
+					       power_off_nb);
+
 	/* disable automatic repower-on */
-	regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_REPCNT,
+	regmap_update_bits(rn5t618->regmap, RN5T618_REPCNT,
 			   RN5T618_REPCNT_REPWRON, 0);
 	/* start power-off sequence */
-	regmap_update_bits(rn5t618_pm_power_off->regmap, RN5T618_SLPCNT,
+	regmap_update_bits(rn5t618->regmap, RN5T618_SLPCNT,
 			   RN5T618_SLPCNT_SWPWROFF, RN5T618_SLPCNT_SWPWROFF);
+
+	return NOTIFY_DONE;
 }
 
 static int rn5t618_i2c_probe(struct i2c_client *i2c,
@@ -85,23 +91,17 @@ static int rn5t618_i2c_probe(struct i2c_client *i2c,
 		return ret;
 	}
 
-	if (!pm_power_off) {
-		rn5t618_pm_power_off = priv;
-		pm_power_off = rn5t618_power_off;
-	}
+	priv->power_off_nb.notifier_call = rn5t618_power_off;
+	priv->power_off_nb.priority = POWER_OFF_PRIORITY_LOW;
+	ret = devm_register_power_off_handler(&i2c->dev, &priv->power_off_nb);
+	if (ret)
+		dev_warn(&i2c->dev, "Failed to register power-off handler\n");
 
 	return 0;
 }
 
 static int rn5t618_i2c_remove(struct i2c_client *i2c)
 {
-	struct rn5t618 *priv = i2c_get_clientdata(i2c);
-
-	if (priv == rn5t618_pm_power_off) {
-		rn5t618_pm_power_off = NULL;
-		pm_power_off = NULL;
-	}
-
 	mfd_remove_devices(&i2c->dev);
 	return 0;
 }
diff --git a/include/linux/mfd/rn5t618.h b/include/linux/mfd/rn5t618.h
index c72d534..21c9c39 100644
--- a/include/linux/mfd/rn5t618.h
+++ b/include/linux/mfd/rn5t618.h
@@ -14,6 +14,7 @@
 #ifndef __LINUX_MFD_RN5T618_H
 #define __LINUX_MFD_RN5T618_H
 
+#include <linux/notifier.h>
 #include <linux/regmap.h>
 
 #define RN5T618_LSIVER			0x00
@@ -223,6 +224,7 @@ enum {
 
 struct rn5t618 {
 	struct regmap *regmap;
+	struct notifier_block power_off_nb;
 };
 
 #endif /* __LINUX_MFD_RN5T618_H */
-- 
1.9.1