regulator: tps65090: Allow setting the overcurrent wait time

The tps65090 regulator allows you to specify how long you want it to
wait before detecting an overcurrent condition.  Allow specifying that
through the device tree (or through platform data).

Signed-off-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Michael Spang <spang@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/regulator/tps65090-regulator.c b/drivers/regulator/tps65090-regulator.c
index 2e92ef6..ca04e9f 100644
--- a/drivers/regulator/tps65090-regulator.c
+++ b/drivers/regulator/tps65090-regulator.c
@@ -28,15 +28,58 @@
 #include <linux/regulator/of_regulator.h>
 #include <linux/mfd/tps65090.h>
 
+#define CTRL_WT_BIT		2 /* Regulator wait time 0 bit */
+
+#define MAX_OVERCURRENT_WAIT	3 /* Overcurrent wait must be <= this */
+
+/**
+ * struct tps65090_regulator - Per-regulator data for a tps65090 regulator
+ *
+ * @dev: Pointer to our device.
+ * @desc: The struct regulator_desc for the regulator.
+ * @rdev: The struct regulator_dev for the regulator.
+ * @overcurrent_wait_valid: True if overcurrent_wait is valid.
+ * @overcurrent_wait: For FETs, the value to put in the WTFET bitfield.
+ */
+
 struct tps65090_regulator {
 	struct device		*dev;
 	struct regulator_desc	*desc;
 	struct regulator_dev	*rdev;
+	bool			overcurrent_wait_valid;
+	int			overcurrent_wait;
 };
 
 static struct regulator_ops tps65090_ext_control_ops = {
 };
 
+/**
+ * tps65090_reg_set_overcurrent_wait - Setup overcurrent wait
+ *
+ * This will set the overcurrent wait time based on what's in the regulator
+ * info.
+ *
+ * @ri:		Overall regulator data
+ * @rdev:	Regulator device
+ *
+ * Return: 0 if no error, non-zero if there was an error writing the register.
+ */
+static int tps65090_reg_set_overcurrent_wait(struct tps65090_regulator *ri,
+					     struct regulator_dev *rdev)
+{
+	int ret;
+
+	ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+				 MAX_OVERCURRENT_WAIT << CTRL_WT_BIT,
+				 ri->overcurrent_wait << CTRL_WT_BIT);
+	if (ret) {
+		dev_err(&rdev->dev, "Error updating overcurrent wait %#x\n",
+			rdev->desc->enable_reg);
+	}
+
+	return ret;
+}
+
 static struct regulator_ops tps65090_reg_contol_ops = {
 	.enable		= regulator_enable_regmap,
 	.disable	= regulator_disable_regmap,
@@ -209,6 +252,11 @@
 			rpdata->gpio = of_get_named_gpio(np,
 					"dcdc-ext-control-gpios", 0);
 
+		if (of_property_read_u32(tps65090_matches[idx].of_node,
+					 "ti,overcurrent-wait",
+					 &rpdata->overcurrent_wait) == 0)
+			rpdata->overcurrent_wait_valid = true;
+
 		tps65090_pdata->reg_pdata[idx] = rpdata;
 	}
 	return tps65090_pdata;
@@ -258,6 +306,8 @@
 		ri = &pmic[num];
 		ri->dev = &pdev->dev;
 		ri->desc = &tps65090_regulator_desc[num];
+		ri->overcurrent_wait_valid = tps_pdata->overcurrent_wait_valid;
+		ri->overcurrent_wait = tps_pdata->overcurrent_wait;
 
 		/*
 		 * TPS5090 DCDC support the control from external digital input.
@@ -299,6 +349,12 @@
 		}
 		ri->rdev = rdev;
 
+		if (ri->overcurrent_wait_valid) {
+			ret = tps65090_reg_set_overcurrent_wait(ri, rdev);
+			if (ret < 0)
+				return ret;
+		}
+
 		/* Enable external control if it is require */
 		if (tps_pdata && is_dcdc(num) && tps_pdata->reg_init_data &&
 				tps_pdata->enable_ext_control) {