mfd: max8907: Add power off control

Add DT property "maxim,system-power-controller" to indicate whether the
PMIC is in charge of controlling the system power. If this is set, the
driver will provide the pm_power_off() function.

Signed-off-by: Stephen Warren <[e-mail]>
Signed-off-by: Samuel Ortiz <[e-mail]>

Documentation/devicetree/bindings/regulator/max8907.txt

···
   property, with valid values listed below. The content of each sub-node
   is defined by the standard binding for regulators; see regulator.txt.
 
+Optional properties:
+- maxim,system-power-controller: Boolean property indicating that the PMIC
+  controls the overall system power.
+
 Valid regulator-compatible values are:
 
   sd1, sd2, sd3, ldo1, ldo2, ldo3, ldo4, ldo5, ldo6, ldo7, ldo8, ldo9, ldo10,
···
 			compatible = "maxim,max8907";
 			reg = <0x3c>;
 			interrupts = <0 86 0x4>;
+
+			maxim,system-power-controller;
 
 			mbatt-supply = <&some_reg>;
 			in-v1-supply = <&mbatt_reg>;

drivers/mfd/max8907.c

···
 	.num_irqs = ARRAY_SIZE(max8907_rtc_irqs),
 };
 
+struct max8907 *max8907_pm_off;
+static void max8907_power_off(void)
+{
+	regmap_update_bits(max8907_pm_off->regmap_gen, MAX8907_REG_RESET_CNFG,
+			MAX8907_MASK_POWER_OFF, MAX8907_MASK_POWER_OFF);
+}
+
 static __devinit int max8907_i2c_probe(struct i2c_client *i2c,
 				       const struct i2c_device_id *id)
 {
 	struct max8907 *max8907;
 	int ret;
+	struct max8907_platform_data *pdata = dev_get_platdata(&i2c->dev);
+	bool pm_off = false;
+
+	if (pdata)
+		pm_off = pdata->pm_off;
+	else if (i2c->dev.of_node)
+		pm_off = of_property_read_bool(i2c->dev.of_node,
+					"maxim,system-power-controller");
 
 	max8907 = devm_kzalloc(&i2c->dev, sizeof(struct max8907), GFP_KERNEL);
 	if (!max8907) {
···
 	if (ret != 0) {
 		dev_err(&i2c->dev, "failed to add MFD devices %d\n", ret);
 		goto err_add_devices;
+	}
+
+	if (pm_off && !pm_power_off) {
+		max8907_pm_off = max8907;
+		pm_power_off = max8907_power_off;
 	}
 
 	return 0;

include/linux/mfd/max8907.h

···
 #define MAX8907_MASK_OUT5V_VINEN	0x10
 #define MAX8907_MASK_OUT5V_ENSRC	0x0E
 #define MAX8907_MASK_OUT5V_EN		0x01
+#define MAX8907_MASK_POWER_OFF		0x40
 
 /* Regulator IDs */
 #define MAX8907_MBATT	0
···
 
 struct max8907_platform_data {
 	struct regulator_init_data *init_data[MAX8907_NUM_REGULATORS];
+	bool pm_off;
 };
 
 struct regmap_irq_chips_data;