regulator: core: Change the unit of ramp_delay from mV/uS to uV/uS

This change makes it possible to set ramp_delay with 0.xxx mV/uS without
truncation issue.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

Documentation/devicetree/bindings/regulator/regulator.txt

@@ -10,7 +10,7 @@ Optional properties:
 - regulator-always-on: boolean, regulator should never be disabled
 - regulator-boot-on: bootloader/firmware enabled regulator
 - <name>-supply: phandle to the parent supply/regulator node
-- regulator-ramp-delay: ramp delay for regulator(in mV/uS)
+- regulator-ramp-delay: ramp delay for regulator(in uV/uS)
 
 Example:
 

drivers/regulator/core.c

@@ -2319,11 +2319,11 @@ int regulator_set_voltage_time_sel(struct regulator_dev *rdev,
 	if (rdev->desc->uV_step) {
 		return DIV_ROUND_UP(rdev->desc->uV_step *
 				    abs(new_selector - old_selector),
-				    ramp_delay * 1000);
+				    ramp_delay);
 	} else if (rdev->desc->volt_table) {
 		return DIV_ROUND_UP(abs(rdev->desc->volt_table[new_selector] -
 					rdev->desc->volt_table[old_selector]),
-				    ramp_delay * 1000);
+				    ramp_delay);
 	} else {
 		rdev_warn(rdev, "Unsupported voltage mapping settings\n");
 	}

include/linux/regulator/driver.h

@@ -173,7 +173,7 @@ enum regulator_type {
  *
  * @min_uV: Voltage given by the lowest selector (if linear mapping)
  * @uV_step: Voltage increase with each selector (if linear mapping)
- * @ramp_delay: Time to settle down after voltage change (unit: mV/us)
+ * @ramp_delay: Time to settle down after voltage change (unit: uV/us)
  * @volt_table: Voltage mapping table (if table based mapping)
  *
  * @vsel_reg: Register for selector when using regulator_regmap_X_voltage_

include/linux/regulator/machine.h

@@ -92,7 +92,7 @@ struct regulator_state {
  *                 mode.
  * @initial_state: Suspend state to set by default.
  * @initial_mode: Mode to set at startup.
- * @ramp_delay: Time to settle down after voltage change (unit: mV/us)
+ * @ramp_delay: Time to settle down after voltage change (unit: uV/us)
  */
 struct regulation_constraints {