mfd: Add support for tps65910 device sleep

Adding support for device sleep through the external input control
signal "SLEEP".
Changing the SLEEP signal state can switch the device into SLEEP and
ACTIVE state.
Also adding sleep configuration for different resources so that they
should be keep on during sleep state of device.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/tps65910.c b/drivers/mfd/tps65910.c
index bf2b25e..ae7f47b 100644
--- a/drivers/mfd/tps65910.c
+++ b/drivers/mfd/tps65910.c
@@ -90,6 +90,66 @@
 	.cache_type = REGCACHE_RBTREE,
 };
 
+static int __init tps65910_sleepinit(struct tps65910 *tps65910,
+		struct tps65910_board *pmic_pdata)
+{
+	struct device *dev = NULL;
+	int ret = 0;
+
+	dev = tps65910->dev;
+
+	if (!pmic_pdata->en_dev_slp)
+		return 0;
+
+	/* enabling SLEEP device state */
+	ret = tps65910_set_bits(tps65910, TPS65910_DEVCTRL,
+				DEVCTRL_DEV_SLP_MASK);
+	if (ret < 0) {
+		dev_err(dev, "set dev_slp failed: %d\n", ret);
+		goto err_sleep_init;
+	}
+
+	/* Return if there is no sleep keepon data. */
+	if (!pmic_pdata->slp_keepon)
+		return 0;
+
+	if (pmic_pdata->slp_keepon->therm_keepon) {
+		ret = tps65910_set_bits(tps65910, TPS65910_SLEEP_KEEP_RES_ON,
+				SLEEP_KEEP_RES_ON_THERM_KEEPON_MASK);
+		if (ret < 0) {
+			dev_err(dev, "set therm_keepon failed: %d\n", ret);
+			goto disable_dev_slp;
+		}
+	}
+
+	if (pmic_pdata->slp_keepon->clkout32k_keepon) {
+		ret = tps65910_set_bits(tps65910, TPS65910_SLEEP_KEEP_RES_ON,
+				SLEEP_KEEP_RES_ON_CLKOUT32K_KEEPON_MASK);
+		if (ret < 0) {
+			dev_err(dev, "set clkout32k_keepon failed: %d\n", ret);
+			goto disable_dev_slp;
+		}
+	}
+
+	if (pmic_pdata->slp_keepon->i2chs_keepon) {
+		ret = tps65910_set_bits(tps65910, TPS65910_SLEEP_KEEP_RES_ON,
+				SLEEP_KEEP_RES_ON_I2CHS_KEEPON_MASK);
+		if (ret < 0) {
+			dev_err(dev, "set i2chs_keepon failed: %d\n", ret);
+			goto disable_dev_slp;
+		}
+	}
+
+	return 0;
+
+disable_dev_slp:
+	tps65910_clear_bits(tps65910, TPS65910_DEVCTRL, DEVCTRL_DEV_SLP_MASK);
+
+err_sleep_init:
+	return ret;
+}
+
+
 static int tps65910_i2c_probe(struct i2c_client *i2c,
 			    const struct i2c_device_id *id)
 {
@@ -140,6 +200,8 @@
 
 	tps65910_irq_init(tps65910, init_data->irq, init_data);
 
+	tps65910_sleepinit(tps65910, pmic_plat_data);
+
 	kfree(init_data);
 	return ret;