[PATCH v6 11/48] mfd: retu: 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 low priority to reflect that the original code
only sets pm_power_off if it was not already set.

Cc: Lee Jones <lee.jones@linaro.org>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v6:
- This patch: No change.
  Global: Replaced priority defines with enum.
v5:
- Rebase to v3.18-rc3
v4:
- Do not use notifiers but internal functions and data structures to manage
  the list of power-off handlers. Drop unused parameters from callbacks, and
  make the power-off function type void
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
- Use dev_warn instead of dev_err

 drivers/mfd/retu-mfd.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/mfd/retu-mfd.c b/drivers/mfd/retu-mfd.c
index 663f8a3..30e746b 100644
--- a/drivers/mfd/retu-mfd.c
+++ b/drivers/mfd/retu-mfd.c
@@ -22,6 +22,7 @@
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/module.h>
+#include <linux/pm.h>
 #include <linux/regmap.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/retu.h>
@@ -43,6 +44,7 @@ struct retu_dev {
 	struct device			*dev;
 	struct mutex			mutex;
 	struct regmap_irq_chip_data	*irq_data;
+	struct power_off_handler_block	power_off_hb;
 };
 
 static struct resource retu_pwrbutton_res[] = {
@@ -81,9 +83,6 @@ static struct regmap_irq_chip retu_irq_chip = {
 	.ack_base	= RETU_REG_IDR,
 };
 
-/* Retu device registered for the power off. */
-static struct retu_dev *retu_pm_power_off;
-
 static struct resource tahvo_usb_res[] = {
 	{
 		.name	= "tahvo-usb",
@@ -165,12 +164,13 @@ int retu_write(struct retu_dev *rdev, u8 reg, u16 data)
 }
 EXPORT_SYMBOL_GPL(retu_write);
 
-static void retu_power_off(void)
+static void retu_power_off(struct power_off_handler_block *this)
 {
-	struct retu_dev *rdev = retu_pm_power_off;
+	struct retu_dev *rdev = container_of(this, struct retu_dev,
+					     power_off_hb);
 	int reg;
 
-	mutex_lock(&retu_pm_power_off->mutex);
+	mutex_lock(&rdev->mutex);
 
 	/* Ignore power button state */
 	regmap_read(rdev->regmap, RETU_REG_CC1, &reg);
@@ -183,7 +183,7 @@ static void retu_power_off(void)
 	for (;;)
 		cpu_relax();
 
-	mutex_unlock(&retu_pm_power_off->mutex);
+	mutex_unlock(&rdev->mutex);
 }
 
 static int retu_regmap_read(void *context, const void *reg, size_t reg_size,
@@ -279,9 +279,14 @@ static int retu_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 		return ret;
 	}
 
-	if (i2c->addr == 1 && !pm_power_off) {
-		retu_pm_power_off = rdev;
-		pm_power_off	  = retu_power_off;
+	if (i2c->addr == 1) {
+		rdev->power_off_hb.handler = retu_power_off;
+		rdev->power_off_hb.priority = POWER_OFF_PRIORITY_LOW;
+		ret = devm_register_power_off_handler(rdev->dev,
+						      &rdev->power_off_hb);
+		if (ret)
+			dev_warn(rdev->dev,
+				 "Failed to register power-off handler\n");
 	}
 
 	return 0;
@@ -291,10 +296,6 @@ static int retu_remove(struct i2c_client *i2c)
 {
 	struct retu_dev *rdev = i2c_get_clientdata(i2c);
 
-	if (retu_pm_power_off == rdev) {
-		pm_power_off	  = NULL;
-		retu_pm_power_off = NULL;
-	}
 	mfd_remove_devices(rdev->dev);
 	regmap_del_irq_chip(i2c->irq, rdev->irq_data);
 
-- 
1.9.1