power: regulator: Add support for gpio regulators

Add support for gpio regulators. As of now this driver caters
to gpio regulators with one gpio. Supports setting voltage values to gpio
regulators and retrieving the values.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/power/regulator/Kconfig b/drivers/power/regulator/Kconfig
index c7e88c00817876be4107a6f6474855f930e49bb8..255eccf4d74ff942a0af0dcaed46d78ef1c20aef 100644 (file)
--- a/drivers/power/regulator/Kconfig
+++ b/drivers/power/regulator/Kconfig
@@ -68,6 +68,14 @@ config DM_REGULATOR_FIXED
        features for fixed value regulators. The driver implements get/set api
        for enable and get only for voltage value.
 
+config DM_REGULATOR_GPIO
+       bool "Enable Driver Model for GPIO REGULATOR"
+       depends on DM_REGULATOR
+       ---help---
+       This config enables implementation of driver-model regulator uclass
+       features for gpio regulators. The driver implements get/set for
+       voltage value.
+
 config REGULATOR_RK808
        bool "Enable driver for RK808 regulators"
        depends on DM_REGULATOR && PMIC_RK808

diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile
index ab461ec3efee14c6bd68e7989356100c358f80a3..e9ae22e266cce8b80c476d0154cbcafd49ecdee3 100644 (file)
--- a/drivers/power/regulator/Makefile
+++ b/drivers/power/regulator/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_DM_REGULATOR_MAX77686) += max77686.o
 obj-$(CONFIG_DM_REGULATOR_PFUZE100) += pfuze100.o
 obj-$(CONFIG_REGULATOR_PWM) += pwm_regulator.o
 obj-$(CONFIG_$(SPL_)DM_REGULATOR_FIXED) += fixed.o
+obj-$(CONFIG_$(SPL_)DM_REGULATOR_GPIO) += gpio-regulator.o
 obj-$(CONFIG_REGULATOR_RK808) += rk808.o
 obj-$(CONFIG_REGULATOR_S5M8767) += s5m8767.o
 obj-$(CONFIG_DM_REGULATOR_SANDBOX) += sandbox.o

diff --git a/drivers/power/regulator/gpio-regulator.c b/drivers/power/regulator/gpio-regulator.c
new file mode 100644 (file)
index 0000000..0a60a9c
--- /dev/null
+++ b/drivers/power/regulator/gpio-regulator.c
@@ -0,0 +1,137 @@
+/*
+ * (C) Copyright 2016 Texas Instruments Incorporated, <www.ti.com>
+ * Keerthy <j-keerthy@ti.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <fdtdec.h>
+#include <errno.h>
+#include <dm.h>
+#include <i2c.h>
+#include <asm/gpio.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+
+#define GPIO_REGULATOR_MAX_STATES      2
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct gpio_regulator_platdata {
+       struct gpio_desc gpio; /* GPIO for regulator voltage control */
+       int states[GPIO_REGULATOR_MAX_STATES];
+       int voltages[GPIO_REGULATOR_MAX_STATES];
+};
+
+static int gpio_regulator_ofdata_to_platdata(struct udevice *dev)
+{
+       struct dm_regulator_uclass_platdata *uc_pdata;
+       struct gpio_regulator_platdata *dev_pdata;
+       struct gpio_desc *gpio;
+       const void *blob = gd->fdt_blob;
+       int node = dev->of_offset;
+       int ret, count, i, j;
+       u32 states_array[8];
+
+       dev_pdata = dev_get_platdata(dev);
+       uc_pdata = dev_get_uclass_platdata(dev);
+       if (!uc_pdata)
+               return -ENXIO;
+
+       /* Set type to gpio */
+       uc_pdata->type = REGULATOR_TYPE_GPIO;
+
+       /*
+        * Get gpio regulator gpio desc
+        * Assuming one GPIO per regulator.
+        * Can be extended later to multiple GPIOs
+        * per gpio-regulator. As of now no instance with multiple
+        * gpios is presnt
+        */
+       gpio = &dev_pdata->gpio;
+       ret = gpio_request_by_name(dev, "gpios", 0, gpio, GPIOD_IS_OUT);
+       if (ret)
+               debug("regulator gpio - not found! Error: %d", ret);
+
+       count = fdtdec_get_int_array_count(blob, node, "states",
+                                          states_array, 8);
+
+       if (!count)
+               return -EINVAL;
+
+       for (i = 0, j = 0; i < count; i += 2) {
+               dev_pdata->voltages[j] = states_array[i];
+               dev_pdata->states[j] = states_array[i + 1];
+               j++;
+       }
+
+       return 0;
+}
+
+static int gpio_regulator_get_value(struct udevice *dev)
+{
+       struct dm_regulator_uclass_platdata *uc_pdata;
+       struct gpio_regulator_platdata *dev_pdata = dev_get_platdata(dev);
+       int enable;
+
+       if (!dev_pdata->gpio.dev)
+               return -ENOSYS;
+
+       uc_pdata = dev_get_uclass_platdata(dev);
+       if (uc_pdata->min_uV > uc_pdata->max_uV) {
+               debug("Invalid constraints for: %s\n", uc_pdata->name);
+               return -EINVAL;
+       }
+
+       enable = dm_gpio_get_value(&dev_pdata->gpio);
+       if (enable == dev_pdata->states[0])
+               return dev_pdata->voltages[0];
+       else
+               return dev_pdata->voltages[1];
+}
+
+static int gpio_regulator_set_value(struct udevice *dev, int uV)
+{
+       struct gpio_regulator_platdata *dev_pdata = dev_get_platdata(dev);
+       int ret;
+       bool enable;
+
+       if (!dev_pdata->gpio.dev)
+               return -ENOSYS;
+
+       if (uV == dev_pdata->voltages[0])
+               enable = dev_pdata->states[0];
+       else if (uV == dev_pdata->voltages[1])
+               enable = dev_pdata->states[1];
+       else
+               return -EINVAL;
+
+       ret = dm_gpio_set_value(&dev_pdata->gpio, enable);
+       if (ret) {
+               error("Can't set regulator : %s gpio to: %d\n", dev->name,
+                     enable);
+               return ret;
+       }
+
+       return 0;
+}
+
+static const struct dm_regulator_ops gpio_regulator_ops = {
+       .get_value      = gpio_regulator_get_value,
+       .set_value      = gpio_regulator_set_value,
+};
+
+static const struct udevice_id gpio_regulator_ids[] = {
+       { .compatible = "regulator-gpio" },
+       { },
+};
+
+U_BOOT_DRIVER(gpio_regulator) = {
+       .name = "gpio regulator",
+       .id = UCLASS_REGULATOR,
+       .ops = &gpio_regulator_ops,
+       .of_match = gpio_regulator_ids,
+       .ofdata_to_platdata = gpio_regulator_ofdata_to_platdata,
+       .platdata_auto_alloc_size = sizeof(struct gpio_regulator_platdata),
+};

diff --git a/include/power/regulator.h b/include/power/regulator.h
index 9bcd728120aa9a53b2f4d1a4ebe157539a7d1675..911956c0b958211cd62b2c3f3d3385bb2f435503 100644 (file)
--- a/include/power/regulator.h
+++ b/include/power/regulator.h
@@ -108,6 +108,7 @@ enum regulator_type {
        REGULATOR_TYPE_BUCK,
        REGULATOR_TYPE_DVS,
        REGULATOR_TYPE_FIXED,
+       REGULATOR_TYPE_GPIO,
        REGULATOR_TYPE_OTHER,
 };