[PATCH v3 18/47] mfd: twl4030-power: 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.

Make twl4030_power_off static as it is only called from the twl4030-power
driver. Drop remove function as it is no longer needed.

Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
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 dev_warn instead of dev_err
- Use devm_register_power_off_handler
- Drop remove function as it is no longer needed.

 drivers/mfd/twl4030-power.c | 29 +++++++++++++++++++----------
 include/linux/i2c/twl.h     |  1 -
 2 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/drivers/mfd/twl4030-power.c b/drivers/mfd/twl4030-power.c
index cf92a6d..e36eea9 100644
--- a/drivers/mfd/twl4030-power.c
+++ b/drivers/mfd/twl4030-power.c
@@ -25,9 +25,10 @@
  */
 
 #include <linux/module.h>
-#include <linux/pm.h>
+#include <linux/notifier.h>
 #include <linux/i2c/twl.h>
 #include <linux/platform_device.h>
+#include <linux/pm.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 
@@ -611,7 +612,8 @@ twl4030_power_configure_resources(const struct twl4030_power_data *pdata)
  * After a successful execution, TWL shuts down the power to the SoC
  * and all peripherals connected to it.
  */
-void twl4030_power_off(void)
+static int twl4030_power_off(struct notifier_block *this, unsigned long unused1,
+			     void *unused2)
 {
 	int err;
 
@@ -619,8 +621,15 @@ void twl4030_power_off(void)
 			       TWL4030_PM_MASTER_P1_SW_EVENTS);
 	if (err)
 		pr_err("TWL4030 Unable to power off\n");
+
+	return NOTIFY_DONE;
 }
 
+static struct notifier_block twl4030_power_off_nb = {
+	.notifier_call = twl4030_power_off,
+	.priority = POWER_OFF_PRIORITY_LOW,
+};
+
 static bool twl4030_power_use_poweroff(const struct twl4030_power_data *pdata,
 					struct device_node *node)
 {
@@ -839,7 +848,9 @@ static int twl4030_power_probe(struct platform_device *pdev)
 	}
 
 	/* Board has to be wired properly to use this feature */
-	if (twl4030_power_use_poweroff(pdata, node) && !pm_power_off) {
+	if (twl4030_power_use_poweroff(pdata, node)) {
+		int ret;
+
 		/* Default for SEQ_OFFSYNC is set, lets ensure this */
 		err = twl_i2c_read_u8(TWL_MODULE_PM_MASTER, &val,
 				      TWL4030_PM_MASTER_CFG_P123_TRANSITION);
@@ -856,7 +867,11 @@ static int twl4030_power_probe(struct platform_device *pdev)
 			}
 		}
 
-		pm_power_off = twl4030_power_off;
+		ret = devm_register_power_off_handler(&pdev->dev,
+						      &twl4030_power_off_nb);
+		if (ret)
+			dev_warn(&pdev->dev,
+				 "Failed to register power-off handler\n");
 	}
 
 relock:
@@ -870,11 +885,6 @@ relock:
 	return err;
 }
 
-static int twl4030_power_remove(struct platform_device *pdev)
-{
-	return 0;
-}
-
 static struct platform_driver twl4030_power_driver = {
 	.driver = {
 		.name	= "twl4030_power",
@@ -882,7 +892,6 @@ static struct platform_driver twl4030_power_driver = {
 		.of_match_table = of_match_ptr(twl4030_power_of_match),
 	},
 	.probe		= twl4030_power_probe,
-	.remove		= twl4030_power_remove,
 };
 
 module_platform_driver(twl4030_power_driver);
diff --git a/include/linux/i2c/twl.h b/include/linux/i2c/twl.h
index 8cfb50f..f8544f1 100644
--- a/include/linux/i2c/twl.h
+++ b/include/linux/i2c/twl.h
@@ -680,7 +680,6 @@ struct twl4030_power_data {
 };
 
 extern int twl4030_remove_script(u8 flags);
-extern void twl4030_power_off(void);
 
 struct twl4030_codec_data {
 	unsigned int digimic_delay; /* in ms */
-- 
1.9.1