regulator: Add over current protection (OCP) support

Some regulators can automatically shut down when they detect an
over current event. Add an op (set_over_current_protection) and a
DT property + constraint to support this capability.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c
index b1c485b..250700c 100644
--- a/drivers/regulator/of_regulator.c
+++ b/drivers/regulator/of_regulator.c
@@ -107,6 +107,9 @@
 	if (!of_property_read_u32(np, "regulator-system-load", &pval))
 		constraints->system_load = pval;
 
+	constraints->over_current_protection = of_property_read_bool(np,
+					"regulator-over-current-protection");
+
 	for (i = 0; i < ARRAY_SIZE(regulator_states); i++) {
 		switch (i) {
 		case PM_SUSPEND_MEM: