dm: regulator: add fixed voltage regulator driver

This driver implements regulator operations for fixed Voltage/Current
value regulators. beside the standard regulator constraints, which are
put into the uclass platform data, a typical fixed regulator node provides
few additional properties like:
- gpio
- gpio-open-drain
- enable-active-high
- startup-delay-us
The only 'gpio' is used by this driver and is kept in structure of type
'fixed_regulator_platdata', as a device platform data (dev->platdata).

The driver implements:
- get_value
- get_current
- get_enable
- set_enable

The regulator calls and commands can be used for fixed-regulator devices,
and the proper error will be returned for prohibited.

Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>

diff --git a/doc/device-tree-bindings/regulator/fixed.txt b/doc/device-tree-bindings/regulator/fixed.txt
new file mode 100644 (file)
index 0000000..4ff39b8
--- /dev/null
+++ b/doc/device-tree-bindings/regulator/fixed.txt
@@ -0,0 +1,38 @@
+Fixed Voltage regulator
+
+Binding:
+The binding is done by the property "compatible" - this is different, than for
+binding by the node prefix (doc/device-tree-bindings/regulator/regulator.txt).
+
+Required properties:
+- compatible: "regulator-fixed"
+- regulator-name: this is required by the regulator uclass
+
+Optional properties:
+- gpio: GPIO to use for enable control
+- regulator constraints (binding info: regulator.txt)
+
+Other kernel-style properties, are currently not used.
+
+Note:
+For the regulator constraints, driver expects that:
+- regulator-min-microvolt is equal to regulator-max-microvolt
+- regulator-min-microamp is equal to regulator-max-microamp
+
+Example:
+fixed_regulator@0 {
+       /* Mandatory */
+       compatible = "regulator-fixed";
+       regulator-name = "LED_3.3V";
+
+       /* Optional: */
+       gpio = <&gpc1 0 GPIO_ACTIVE_LOW>;
+
+       /* Optional for regulator uclass */
+       regulator-min-microvolt = <3300000>;
+       regulator-max-microvolt = <3300000>;
+       regulator-min-microamp = <15000>;
+       regulator-max-microamp = <15000>;
+       regulator-always-on;
+       regulator-boot-on;
+};

diff --git a/drivers/power/regulator/Kconfig b/drivers/power/regulator/Kconfig
index 0cdfabc5bf345c55bc286f6f35265a28a357f4d1..54ce188743c80765bbc1c8f217199b5dc95387a2 100644 (file)
--- a/drivers/power/regulator/Kconfig
+++ b/drivers/power/regulator/Kconfig
@@ -23,3 +23,11 @@ config DM_REGULATOR_MAX77686
        This config enables implementation of driver-model regulator uclass
        features for REGULATOR MAX77686. The driver implements get/set api for:
        value, enable and mode.
+
+config DM_REGULATOR_FIXED
+       bool "Enable Driver Model for REGULATOR Fixed value"
+       depends on DM_REGULATOR
+       ---help---
+       This config enables implementation of driver-model regulator uclass
+       features for fixed value regulators. The driver implements get/set api
+       for enable and get only for voltage value.

diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile
index f9c4e6d9ec412769b22eb28de9f1cd0b3fa439dd..cc8326d78db01fa2803f6e9a6d9b0cea24e36961 100644 (file)
--- a/drivers/power/regulator/Makefile
+++ b/drivers/power/regulator/Makefile
@@ -7,3 +7,4 @@
 
 obj-$(CONFIG_DM_REGULATOR) += regulator-uclass.o
 obj-$(CONFIG_DM_REGULATOR_MAX77686) += max77686.o
+obj-$(CONFIG_DM_REGULATOR_FIXED) += fixed.o

diff --git a/drivers/power/regulator/fixed.c b/drivers/power/regulator/fixed.c
new file mode 100644 (file)
index 0000000..d053817
--- /dev/null
+++ b/drivers/power/regulator/fixed.c
@@ -0,0 +1,126 @@
+/*
+ *  Copyright (C) 2015 Samsung Electronics
+ *
+ *  Przemyslaw Marczak <p.marczak@samsung.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>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct fixed_regulator_platdata {
+       struct gpio_desc gpio; /* GPIO for regulator enable control */
+};
+
+static int fixed_regulator_ofdata_to_platdata(struct udevice *dev)
+{
+       struct dm_regulator_uclass_platdata *uc_pdata;
+       struct fixed_regulator_platdata *dev_pdata;
+       struct gpio_desc *gpio;
+       int ret;
+
+       dev_pdata = dev_get_platdata(dev);
+       uc_pdata = dev_get_uclass_platdata(dev);
+       if (!uc_pdata)
+               return -ENXIO;
+
+       /* Set type to fixed */
+       uc_pdata->type = REGULATOR_TYPE_FIXED;
+
+       /* Get fixed regulator gpio desc */
+       gpio = &dev_pdata->gpio;
+       ret = gpio_request_by_name(dev, "gpio", 0, gpio, GPIOD_IS_OUT);
+       if (ret)
+               debug("Fixed regulator gpio - not found! Error: %d", ret);
+
+       return 0;
+}
+
+static int fixed_regulator_get_value(struct udevice *dev)
+{
+       struct dm_regulator_uclass_platdata *uc_pdata;
+
+       uc_pdata = dev_get_uclass_platdata(dev);
+       if (!uc_pdata)
+               return -ENXIO;
+
+       if (uc_pdata->min_uV != uc_pdata->max_uV) {
+               debug("Invalid constraints for: %s\n", uc_pdata->name);
+               return -EINVAL;
+       }
+
+       return uc_pdata->min_uV;
+}
+
+static int fixed_regulator_get_current(struct udevice *dev)
+{
+       struct dm_regulator_uclass_platdata *uc_pdata;
+
+       uc_pdata = dev_get_uclass_platdata(dev);
+       if (!uc_pdata)
+               return -ENXIO;
+
+       if (uc_pdata->min_uA != uc_pdata->max_uA) {
+               debug("Invalid constraints for: %s\n", uc_pdata->name);
+               return -EINVAL;
+       }
+
+       return uc_pdata->min_uA;
+}
+
+static bool fixed_regulator_get_enable(struct udevice *dev)
+{
+       struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
+
+       if (!dev_pdata->gpio.dev)
+               return false;
+
+       return dm_gpio_get_value(&dev_pdata->gpio);
+}
+
+static int fixed_regulator_set_enable(struct udevice *dev, bool enable)
+{
+       struct fixed_regulator_platdata *dev_pdata = dev_get_platdata(dev);
+       int ret;
+
+       if (!dev_pdata->gpio.dev)
+               return -ENOSYS;
+
+       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 fixed_regulator_ops = {
+       .get_value      = fixed_regulator_get_value,
+       .get_current    = fixed_regulator_get_current,
+       .get_enable     = fixed_regulator_get_enable,
+       .set_enable     = fixed_regulator_set_enable,
+};
+
+static const struct udevice_id fixed_regulator_ids[] = {
+       { .compatible = "regulator-fixed" },
+       { },
+};
+
+U_BOOT_DRIVER(fixed_regulator) = {
+       .name = "fixed regulator",
+       .id = UCLASS_REGULATOR,
+       .ops = &fixed_regulator_ops,
+       .of_match = fixed_regulator_ids,
+       .ofdata_to_platdata = fixed_regulator_ofdata_to_platdata,
+       .platdata_auto_alloc_size = sizeof(struct fixed_regulator_platdata),
+};