regulator: Add input current limit support

Some regulators can limit their input current (typically annotated
as ilim). Add an op (set_input_current_limit) and a DT property +
constraint to support this.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/of_regulator.c

@@ -58,6 +58,10 @@ static void of_get_regulation_constraints(struct device_node *np,
 	if (!of_property_read_u32(np, "regulator-max-microamp", &pval))
 		constraints->max_uA = pval;
 
+	if (!of_property_read_u32(np, "regulator-input-current-limit-microamp",
+				  &pval))
+		constraints->ilim_uA = pval;
+
 	/* Current change possible? */
 	if (constraints->min_uA != constraints->max_uA)
 		constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;