regulator: max77686: Add GPIO control

Add enable control over GPIO for regulators supporting this: LDO20,
LDO21, LDO22, buck8 and buck9.

This is needed for proper (and full) configuration of the Maxim 77686
PMIC without creating redundant 'regulator-fixed' entries.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 65 insertions, 5 deletions

diff --git a/drivers/regulator/max77686.c b/drivers/regulator/max77686.c
index 10d206266ac2..15fb1416bfbd 100644
--- a/drivers/regulator/max77686.c
+++ b/drivers/regulator/max77686.c
@@ -26,6 +26,7 @@
 #include <linux/bug.h>
 #include <linux/err.h>
 #include <linux/gpio.h>
+#include <linux/of_gpio.h>
 #include <linux/slab.h>
 #include <linux/platform_device.h>
 #include <linux/regulator/driver.h>
@@ -46,6 +47,11 @@
 #define MAX77686_DVS_UVSTEP     12500
 
 /*
+ * Value for configuring buck[89] and LDO{20,21,22} as GPIO control.
+ * It is the same as 'off' for other regulators.
+ */
+#define MAX77686_GPIO_CONTROL           0x0
+/*
  * Values used for configuring LDOs and bucks.
  * Forcing low power mode: LDO1, 3-5, 9, 13, 17-26
  */
@@ -82,6 +88,8 @@ enum max77686_ramp_rate {
 };
 
 struct max77686_data {
+        u64 gpio_enabled:MAX77686_REGULATORS;
+
         /* Array indexed by regulator id */
         unsigned int opmode[MAX77686_REGULATORS];
 };
@@ -100,6 +108,26 @@ static unsigned int max77686_get_opmode_shift(int id)
         }
 }
 
+/*
+ * When regulator is configured for GPIO control then it
+ * replaces "normal" mode. Any change from low power mode to normal
+ * should actually change to GPIO control.
+ * Map normal mode to proper value for such regulators.
+ */
+static unsigned int max77686_map_normal_mode(struct max77686_data *max77686,
+                                             int id)
+{
+        switch (id) {
+        case MAX77686_BUCK8:
+        case MAX77686_BUCK9:
+        case MAX77686_LDO20 ... MAX77686_LDO22:
+                if (max77686->gpio_enabled & (1 << id))
+                        return MAX77686_GPIO_CONTROL;
+        }
+
+        return MAX77686_NORMAL;
+}
+
 /* Some BUCKs and LDOs supports Normal[ON/OFF] mode during suspend */
 static int max77686_set_suspend_disable(struct regulator_dev *rdev)
 {
@@ -136,7 +164,7 @@ static int max77686_set_suspend_mode(struct regulator_dev *rdev,
                 val = MAX77686_LDO_LOWPOWER_PWRREQ;
                 break;
         case REGULATOR_MODE_NORMAL:                     /* ON in Normal Mode */
-                val = MAX77686_NORMAL;
+                val = max77686_map_normal_mode(max77686, id);
                 break;
         default:
                 pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
@@ -160,7 +188,7 @@ static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
 {
         unsigned int val;
         struct max77686_data *max77686 = rdev_get_drvdata(rdev);
-        int ret;
+        int ret, id = rdev_get_id(rdev);
 
         switch (mode) {
         case REGULATOR_MODE_STANDBY:                    /* switch off */
@@ -170,7 +198,7 @@ static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
                 val = MAX77686_LDO_LOWPOWER_PWRREQ;
                 break;
         case REGULATOR_MODE_NORMAL:                     /* ON in Normal Mode */
-                val = MAX77686_NORMAL;
+                val = max77686_map_normal_mode(max77686, id);
                 break;
         default:
                 pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
@@ -184,7 +212,7 @@ static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
         if (ret)
                 return ret;
 
-        max77686->opmode[rdev_get_id(rdev)] = val;
+        max77686->opmode[id] = val;
         return 0;
 }
 
@@ -197,7 +225,7 @@ static int max77686_enable(struct regulator_dev *rdev)
         shift = max77686_get_opmode_shift(id);
 
         if (max77686->opmode[id] == MAX77686_OFF_PWRREQ)
-                max77686->opmode[id] = MAX77686_NORMAL;
+                max77686->opmode[id] = max77686_map_normal_mode(max77686, id);
 
         return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
                                   rdev->desc->enable_mask,
@@ -229,6 +257,36 @@ static int max77686_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
                                   MAX77686_RAMP_RATE_MASK, ramp_value << 6);
 }
 
+static int max77686_of_parse_cb(struct device_node *np,
+                const struct regulator_desc *desc,
+                struct regulator_config *config)
+{
+        struct max77686_data *max77686 = config->driver_data;
+
+        switch (desc->id) {
+        case MAX77686_BUCK8:
+        case MAX77686_BUCK9:
+        case MAX77686_LDO20 ... MAX77686_LDO22:
+                config->ena_gpio = of_get_named_gpio(np,
+                                        "maxim,ena-gpios", 0);
+                config->ena_gpio_flags = GPIOF_OUT_INIT_HIGH;
+                config->ena_gpio_initialized = true;
+                break;
+        default:
+                return 0;
+        }
+
+        if (gpio_is_valid(config->ena_gpio)) {
+                max77686->gpio_enabled |= (1 << desc->id);
+
+                return regmap_update_bits(config->regmap, desc->enable_reg,
+                                          desc->enable_mask,
+                                          MAX77686_GPIO_CONTROL);
+        }
+
+        return 0;
+}
+
 static struct regulator_ops max77686_ops = {
         .list_voltage           = regulator_list_voltage_linear,
         .map_voltage            = regulator_map_voltage_linear,
@@ -283,6 +341,7 @@ static struct regulator_ops max77686_buck_dvs_ops = {
         .name           = "LDO"#num,                                    \
         .of_match       = of_match_ptr("LDO"#num),                      \
         .regulators_node        = of_match_ptr("voltage-regulators"),   \
+        .of_parse_cb    = max77686_of_parse_cb,                         \
         .id             = MAX77686_LDO##num,                            \
         .ops            = &max77686_ops,                                \
         .type           = REGULATOR_VOLTAGE,                            \
@@ -355,6 +414,7 @@ static struct regulator_ops max77686_buck_dvs_ops = {
         .name           = "BUCK"#num,                                   \
         .of_match       = of_match_ptr("BUCK"#num),                     \
         .regulators_node        = of_match_ptr("voltage-regulators"),   \
+        .of_parse_cb    = max77686_of_parse_cb,                         \
         .id             = MAX77686_BUCK##num,                           \
         .ops            = &max77686_ops,                                \
         .type           = REGULATOR_VOLTAGE,                            \