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>

diff --git a/Documentation/devicetree/bindings/regulator/regulator.txt b/Documentation/devicetree/bindings/regulator/regulator.txt
index 4b1df61ccbd7f879bcadb97e78aac6cab9651500..e29db73e55f4a31985d41003b80c649e508dff3a 100644 (file)
--- a/Documentation/devicetree/bindings/regulator/regulator.txt
+++ b/Documentation/devicetree/bindings/regulator/regulator.txt
@@ -7,6 +7,7 @@ Optional properties:
 - regulator-microvolt-offset: Offset applied to voltages to compensate for voltage drops
 - regulator-min-microamp: smallest current consumers may set
 - regulator-max-microamp: largest current consumers may set
+- regulator-input-current-limit-microamp: maximum input current regulator allows
 - regulator-always-on: boolean, regulator should never be disabled
 - regulator-boot-on: bootloader/firmware enabled regulator
 - regulator-allow-bypass: allow the regulator to go into bypass mode

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 6dfb2d6c19aefc64ac086371349b908459c22cb5..ba565416d1d0a9f198757e9f62da26adba9c5fd9 100644 (file)
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1008,6 +1008,15 @@ static int set_machine_constraints(struct regulator_dev *rdev,
        if (ret != 0)
                goto out;
 
+       if (rdev->constraints->ilim_uA && ops->set_input_current_limit) {
+               ret = ops->set_input_current_limit(rdev,
+                                                  rdev->constraints->ilim_uA);
+               if (ret < 0) {
+                       rdev_err(rdev, "failed to set input limit\n");
+                       goto out;
+               }
+       }
+
        /* do we need to setup our suspend state */
        if (rdev->constraints->initial_state) {
                ret = suspend_prepare(rdev, rdev->constraints->initial_state);

diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c
index 207da037cd2d99f1fb1647458fe7faa3737ecbcb..f025c1047d0ae1d68ffaa4a8ae2ff46f57640443 100644 (file)
--- a/drivers/regulator/of_regulator.c
+++ b/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;

diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h
index e0635d0894aafadd08be844c3d8aa71a2ae8de43..125264f8be9318e3423cff3f884e24f5dc2a4332 100644 (file)
--- a/include/linux/regulator/driver.h
+++ b/include/linux/regulator/driver.h
@@ -91,6 +91,7 @@ struct regulator_linear_range {
  * @set_current_limit: Configure a limit for a current-limited regulator.
  *                     The driver should select the current closest to max_uA.
  * @get_current_limit: Get the configured limit for a current-limited regulator.
+ * @set_input_current_limit: Configure an input limit.
  *
  * @set_mode: Set the configured operating mode for the regulator.
  * @get_mode: Get the configured operating mode for the regulator.
@@ -145,6 +146,8 @@ struct regulator_ops {
                                 int min_uA, int max_uA);
        int (*get_current_limit) (struct regulator_dev *);
 
+       int (*set_input_current_limit) (struct regulator_dev *, int lim_uA);
+
        /* enable/disable regulator */
        int (*enable) (struct regulator_dev *);
        int (*disable) (struct regulator_dev *);

diff --git a/include/linux/regulator/machine.h b/include/linux/regulator/machine.h
index 7f7d0a3fe1e10ede2583d525f11c6183adcae40f..85a3b457de518f937a2f1b0ba9c7120d090c6369 100644 (file)
--- a/include/linux/regulator/machine.h
+++ b/include/linux/regulator/machine.h
@@ -75,6 +75,7 @@ struct regulator_state {
  *
  * @min_uA: Smallest current consumers may set.
  * @max_uA: Largest current consumers may set.
+ * @ilim_uA: Maximum input current.
  * @system_load: Load that isn't captured by any consumer requests.
  *
  * @valid_modes_mask: Mask of modes which may be configured by consumers.
@@ -113,6 +114,7 @@ struct regulation_constraints {
        /* current output range (inclusive) - for current control */
        int min_uA;
        int max_uA;
+       int ilim_uA;
 
        int system_load;