mfd: mt6397: Modify suspend/resume behavior

Some pmics don't need backup interrupt settings, so we change to use
pm notifier for the pmics which are necessary to store settings.

Signed-off-by: Hsin-Hsiung Wang <[e-mail]>
Signed-off-by: Lee Jones <[e-mail]>

drivers/mfd/mt6397-core.c

···
 	}
 };
 
-#ifdef CONFIG_PM_SLEEP
-static int mt6397_irq_suspend(struct device *dev)
-{
-	struct mt6397_chip *chip = dev_get_drvdata(dev);
-
-	regmap_write(chip->regmap, chip->int_con[0], chip->wake_mask[0]);
-	regmap_write(chip->regmap, chip->int_con[1], chip->wake_mask[1]);
-
-	enable_irq_wake(chip->irq);
-
-	return 0;
-}
-
-static int mt6397_irq_resume(struct device *dev)
-{
-	struct mt6397_chip *chip = dev_get_drvdata(dev);
-
-	regmap_write(chip->regmap, chip->int_con[0], chip->irq_masks_cur[0]);
-	regmap_write(chip->regmap, chip->int_con[1], chip->irq_masks_cur[1]);
-
-	disable_irq_wake(chip->irq);
-
-	return 0;
-}
-#endif
-
-static SIMPLE_DEV_PM_OPS(mt6397_pm_ops, mt6397_irq_suspend,
-			mt6397_irq_resume);
-
 struct chip_data {
 	u32 cid_addr;
 	u32 cid_shift;
···
 	.driver = {
 		.name = "mt6397",
 		.of_match_table = of_match_ptr(mt6397_of_match),
-		.pm = &mt6397_pm_ops,
 	},
 	.id_table = mt6397_id,
 };

drivers/mfd/mt6397-irq.c

···
 #include <linux/of_irq.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
+#include <linux/suspend.h>
 #include <linux/mfd/mt6323/core.h>
 #include <linux/mfd/mt6323/registers.h>
 #include <linux/mfd/mt6397/core.h>
···
 static void mt6397_irq_handle_reg(struct mt6397_chip *mt6397, int reg,
 				  int irqbase)
 {
-	unsigned int status;
+	unsigned int status = 0;
 	int i, irq, ret;
 
 	ret = regmap_read(mt6397->regmap, reg, &status);
···
 	.map = mt6397_irq_domain_map,
 };
 
+static int mt6397_irq_pm_notifier(struct notifier_block *notifier,
+				  unsigned long pm_event, void *unused)
+{
+	struct mt6397_chip *chip =
+		container_of(notifier, struct mt6397_chip, pm_nb);
+
+	switch (pm_event) {
+	case PM_SUSPEND_PREPARE:
+		regmap_write(chip->regmap,
+			     chip->int_con[0], chip->wake_mask[0]);
+		regmap_write(chip->regmap,
+			     chip->int_con[1], chip->wake_mask[1]);
+		enable_irq_wake(chip->irq);
+		break;
+
+	case PM_POST_SUSPEND:
+		regmap_write(chip->regmap,
+			     chip->int_con[0], chip->irq_masks_cur[0]);
+		regmap_write(chip->regmap,
+			     chip->int_con[1], chip->irq_masks_cur[1]);
+		disable_irq_wake(chip->irq);
+		break;
+
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
 int mt6397_irq_init(struct mt6397_chip *chip)
 {
 	int ret;
···
 	regmap_write(chip->regmap, chip->int_con[0], 0x0);
 	regmap_write(chip->regmap, chip->int_con[1], 0x0);
 
+	chip->pm_nb.notifier_call = mt6397_irq_pm_notifier;
 	chip->irq_domain = irq_domain_add_linear(chip->dev->of_node,
 						 MT6397_IRQ_NR,
 						 &mt6397_irq_domain_ops,
···
 		return ret;
 	}
 
+	register_pm_notifier(&chip->pm_nb);
 	return 0;
 }

include/linux/mfd/mt6397/core.h

···
 #define __MFD_MT6397_CORE_H__
 
 #include <linux/mutex.h>
+#include <linux/notifier.h>
 
 enum chip_id {
 	MT6323_CHIP_ID = 0x23,
···
 struct mt6397_chip {
 	struct device *dev;
 	struct regmap *regmap;
+	struct notifier_block pm_nb;
 	int irq;
 	struct irq_domain *irq_domain;
 	struct mutex irqlock;