mfd: palmas: Add power off control

Hook up "pm_power_off" to palmas power off routine if there is DT
property "ti,system-power-controller" defined, so platform which is
powered by this regulator can be powered off properly.

Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Mallikarjun Kasoju <mkasoju@nvidia.com>
Signed-off-by: Bill Huang <bilhuang@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Documentation/devicetree/bindings/regulator/palmas-pmic.txt

@@ -37,6 +37,9 @@ Optional nodes:
 	       ti,smps-range - OTP has the wrong range set for the hardware so override
 	       0 - low range, 1 - high range.
 
+- ti,system-power-controller: Telling whether or not this pmic is controlling
+			      the system power.
+
 Example:
 
 #include <dt-bindings/interrupt-controller/irq.h>
@@ -49,6 +52,8 @@ pmic {
 
 	ti,ldo6-vibrator;
 
+	ti,system-power-controller;
+
 	regulators {
 		smps12_reg : smps12 {
 			regulator-name = "smps12";

drivers/mfd/palmas.c

@@ -229,6 +229,32 @@ static void palmas_dt_to_pdata(struct i2c_client *i2c,
 					PALMAS_POWER_CTRL_ENABLE2_MASK;
 	if (i2c->irq)
 		palmas_set_pdata_irq_flag(i2c, pdata);
+
+	pdata->pm_off = of_property_read_bool(node,
+			"ti,system-power-controller");
+}
+
+static struct palmas *palmas_dev;
+static void palmas_power_off(void)
+{
+	unsigned int addr;
+	int ret, slave;
+
+	if (!palmas_dev)
+		return;
+
+	slave = PALMAS_BASE_TO_SLAVE(PALMAS_PMU_CONTROL_BASE);
+	addr = PALMAS_BASE_TO_REG(PALMAS_PMU_CONTROL_BASE, PALMAS_DEV_CTRL);
+
+	ret = regmap_update_bits(
+			palmas_dev->regmap[slave],
+			addr,
+			PALMAS_DEV_CTRL_DEV_ON,
+			0);
+
+	if (ret)
+		pr_err("%s: Unable to write to DEV_CTRL_DEV_ON: %d\n",
+				__func__, ret);
 }
 
 static unsigned int palmas_features = PALMAS_PMIC_FEATURE_SMPS10_BOOST;
@@ -423,10 +449,13 @@ no_irq:
 	 */
 	if (node) {
 		ret = of_platform_populate(node, NULL, NULL, &i2c->dev);
-		if (ret < 0)
+		if (ret < 0) {
 			goto err_irq;
-		else
+		} else if (pdata->pm_off && !pm_power_off) {
+			palmas_dev = palmas;
+			pm_power_off = palmas_power_off;
 			return ret;
+		}
 	}
 
 	return ret;

include/linux/mfd/palmas.h

@@ -258,6 +258,7 @@ struct palmas_platform_data {
 	 */
 	int mux_from_pdata;
 	u8 pad1, pad2;
+	bool pm_off;
 
 	struct palmas_pmic_platform_data *pmic_pdata;
 	struct palmas_gpadc_platform_data *gpadc_pdata;