[PATCH 6/8] regulator: max77686: Add external GPIO control
Krzysztof Kozlowski
k.kozlowski at samsung.com
Mon Oct 27 08:03:44 PDT 2014
Add 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 at samsung.com>
---
drivers/regulator/max77686.c | 101 ++++++++++++++++++++++++++++++++++++++++---
1 file changed, 96 insertions(+), 5 deletions(-)
diff --git a/drivers/regulator/max77686.c b/drivers/regulator/max77686.c
index e5738c363f07..c54a8603f5b2 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 external control.
+ * It is the same as 'off' for other regulators.
+ */
+#define MAX77686_EXT_CONTROL 0x0
+/*
* Values used for configuring LDOs and bucks.
* Forcing low power mode: LDO1, 3-5, 9, 13, 17-26
*/
@@ -85,6 +91,9 @@ struct max77686_data {
struct max77686_regulator_data *regulators;
int num_regulators;
+ /* Array of size num_regulators with GPIOs for external control. */
+ int *ext_control_gpio;
+
unsigned int opmode[MAX77686_REGULATORS];
};
@@ -102,6 +111,28 @@ static unsigned int max77686_get_opmode_shift(int id)
}
}
+/*
+ * When regulator is configured for external control then it
+ * replaces "normal" mode. Any change from low power mode to normal
+ * should actually change to external control.
+ * Map normal mode to proper value for such regulators.
+ */
+static int max77686_map_normal_mode(struct max77686_data *max77686, int id)
+{
+ switch (id) {
+ case MAX77686_BUCK8:
+ case MAX77686_BUCK9:
+ if (gpio_is_valid(max77686->ext_control_gpio[id]))
+ return MAX77686_EXT_CONTROL;
+
+ case MAX77686_LDO20 ... MAX77686_LDO22:
+ if (gpio_is_valid(max77686->ext_control_gpio[id]))
+ return MAX77686_EXT_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)
{
@@ -138,7 +169,7 @@ 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",
@@ -162,7 +193,7 @@ 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 */
@@ -172,7 +203,7 @@ 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",
@@ -186,7 +217,7 @@ 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;
}
@@ -199,7 +230,7 @@ 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,
@@ -433,6 +464,42 @@ static const struct regulator_desc regulators[] = {
regulator_desc_buck(9),
};
+static int max77686_enable_ext_control(struct regulator_dev *rdev)
+{
+ return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ rdev->desc->enable_mask,
+ MAX77686_EXT_CONTROL);
+}
+
+static void max77686_pmic_dt_parse_ext_control_gpio(struct platform_device *pdev,
+ struct max77686_regulator_data *rdata,
+ struct max77686_data *max77686)
+{
+ int *gpio = max77686->ext_control_gpio;
+ unsigned int i;
+ unsigned int valid_regulators[5] = { MAX77686_LDO20, MAX77686_LDO21,
+ MAX77686_LDO22, MAX77686_BUCK8, MAX77686_BUCK9 };
+
+ /*
+ * 0 is a valid GPIO so initialize all GPIOs to negative value
+ * to indicate that external control won't be used for this regulator.
+ */
+ for (i = 0; i < max77686->num_regulators; i++)
+ max77686->ext_control_gpio[i] = -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(valid_regulators); i++) {
+ unsigned int reg = valid_regulators[i];
+
+ if (!rdata[reg].initdata || !rdata[reg].of_node)
+ continue;
+
+ gpio[reg] = of_get_named_gpio(rdata[reg].of_node, "gpio", 0);
+ if (gpio_is_valid(gpio[reg]))
+ dev_dbg(&pdev->dev, "Using GPIO %d for ext-control over %d/%s\n",
+ gpio[reg], reg, rdata[reg].of_node->name);
+ }
+}
+
static int max77686_pmic_dt_parse(struct platform_device *pdev,
struct max77686_data *max77686)
{
@@ -457,6 +524,14 @@ static int max77686_pmic_dt_parse(struct platform_device *pdev,
return -ENOMEM;
}
+ max77686->ext_control_gpio = devm_kmalloc_array(&pdev->dev,
+ max77686->num_regulators,
+ sizeof(*max77686->ext_control_gpio), GFP_KERNEL);
+ if (!max77686->ext_control_gpio) {
+ of_node_put(regulators_np);
+ return -ENOMEM;
+ }
+
for (i = 0; i < max77686->num_regulators; i++) {
rmatch.name = regulators[i].name;
rmatch.init_data = NULL;
@@ -466,7 +541,9 @@ static int max77686_pmic_dt_parse(struct platform_device *pdev,
rdata[i].of_node = rmatch.of_node;
}
+ max77686_pmic_dt_parse_ext_control_gpio(pdev, rdata, max77686);
max77686->regulators = rdata;
+
of_node_put(regulators_np);
return 0;
@@ -499,6 +576,7 @@ static int max77686_pmic_probe(struct platform_device *pdev)
config.dev = &pdev->dev;
config.regmap = iodev->regmap;
config.driver_data = max77686;
+ config.ena_gpio_flags = GPIOF_OUT_INIT_HIGH;
platform_set_drvdata(pdev, max77686);
for (i = 0; i < MAX77686_REGULATORS; i++) {
@@ -506,6 +584,8 @@ static int max77686_pmic_probe(struct platform_device *pdev)
config.init_data = max77686->regulators[i].initdata;
config.of_node = max77686->regulators[i].of_node;
+ config.ena_gpio = max77686->ext_control_gpio[i];
+ config.ena_gpio_initialized = true;
max77686->opmode[i] = MAX77686_NORMAL;
@@ -516,6 +596,17 @@ static int max77686_pmic_probe(struct platform_device *pdev)
"regulator init failed for %d\n", i);
return PTR_ERR(rdev);
}
+
+ if (gpio_is_valid(config.ena_gpio)) {
+ ret = max77686_enable_ext_control(rdev);
+
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "regulator enable ext control failed for %d\n",
+ i);
+ return ret;
+ }
+ }
}
return 0;
--
1.9.1
More information about the linux-arm-kernel
mailing list