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[v3] regulator: Versatile Express regulator driver

Message ID 1348509414-21261-2-git-send-email-pawel.moll@arm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Pawel Moll Sept. 24, 2012, 5:56 p.m. UTC
Implementation of the regulator framework driver for the
Versatile Express voltage control. Devices without
voltage constraints (ie. "regulator-[min|max]-microvolt"
properties in the DT node) are treated as fixed (or rather
read-only) regulators.

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
---
 .../devicetree/bindings/regulator/vexpress.txt     |   32 +++++
 drivers/regulator/Kconfig                          |    7 +
 drivers/regulator/Makefile                         |    1 +
 drivers/regulator/vexpress.c                       |  146 ++++++++++++++++++++
 4 files changed, 186 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/regulator/vexpress.txt
 create mode 100644 drivers/regulator/vexpress.c

Hi Mark,

This is an updated version of the VE driver, depending on the continuous
voltage range change instead of the linear mapping. I've also added the
DT node documentation.

Pawel

Comments

Mark Brown Oct. 11, 2012, 4:50 a.m. UTC | #1
On Mon, Sep 24, 2012 at 06:56:54PM +0100, Pawel Moll wrote:
> Implementation of the regulator framework driver for the
> Versatile Express voltage control. Devices without
> voltage constraints (ie. "regulator-[min|max]-microvolt"
> properties in the DT node) are treated as fixed (or rather
> read-only) regulators.

Applied, thanks.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/regulator/vexpress.txt b/Documentation/devicetree/bindings/regulator/vexpress.txt
new file mode 100644
index 0000000..d775f72
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/vexpress.txt
@@ -0,0 +1,32 @@ 
+Versatile Express voltage regulators
+------------------------------------
+
+Requires node properties:
+- "compatible" value: "arm,vexpress-volt"
+- "arm,vexpress-sysreg,func" when controlled via vexpress-sysreg
+  (see Documentation/devicetree/bindings/arm/vexpress-sysreg.txt
+  for more details)
+
+Required regulator properties:
+- "regulator-name"
+- "regulator-always-on"
+
+Optional regulator properties:
+- "regulator-min-microvolt"
+- "regulator-max-microvolt"
+
+See Documentation/devicetree/bindings/regulator/regulator.txt
+for more details about the regulator properties.
+
+When no "regulator-[min|max]-microvolt" properties are defined,
+the device is treated as fixed (or rather "read-only") regulator.
+
+Example:
+	volt@0 {
+		compatible = "arm,vexpress-volt";
+		arm,vexpress-sysreg,func = <2 0>;
+		regulator-name = "Cores";
+		regulator-min-microvolt = <800000>;
+		regulator-max-microvolt = <1050000>;
+		regulator-always-on;
+	};
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 4e932cc..a823951 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -404,6 +404,13 @@  config REGULATOR_TWL4030
 	  This driver supports the voltage regulators provided by
 	  this family of companion chips.
 
+config REGULATOR_VEXPRESS
+	tristate "Versatile Express regulators"
+	depends on VEXPRESS_CONFIG
+	help
+	  This driver provides support for voltage regulators available
+	  on the ARM Ltd's Versatile Express platform.
+
 config REGULATOR_WM831X
 	tristate "Wolfson Microelectronics WM831x PMIC regulators"
 	depends on MFD_WM831X
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 3342615..0d4e10f 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -55,6 +55,7 @@  obj-$(CONFIG_REGULATOR_TPS6586X) += tps6586x-regulator.o
 obj-$(CONFIG_REGULATOR_TPS65910) += tps65910-regulator.o
 obj-$(CONFIG_REGULATOR_TPS65912) += tps65912-regulator.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o
+obj-$(CONFIG_REGULATOR_VEXPRESS) += vexpress.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-ldo.o
diff --git a/drivers/regulator/vexpress.c b/drivers/regulator/vexpress.c
new file mode 100644
index 0000000..1702945
--- /dev/null
+++ b/drivers/regulator/vexpress.c
@@ -0,0 +1,146 @@ 
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#define DRVNAME "vexpress-regulator"
+#define pr_fmt(fmt) DRVNAME ": " fmt
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/vexpress.h>
+
+struct vexpress_regulator {
+	struct regulator_desc desc;
+	struct regulator_dev *regdev;
+	struct vexpress_config_func *func;
+};
+
+static int vexpress_regulator_get_voltage(struct regulator_dev *regdev)
+{
+	struct vexpress_regulator *reg = rdev_get_drvdata(regdev);
+	u32 uV;
+	int err = vexpress_config_read(reg->func, 0, &uV);
+
+	return err ? err : uV;
+}
+
+static int vexpress_regulator_set_voltage(struct regulator_dev *regdev,
+		int min_uV, int max_uV, unsigned *selector)
+{
+	struct vexpress_regulator *reg = rdev_get_drvdata(regdev);
+
+	return vexpress_config_write(reg->func, 0, min_uV);
+}
+
+static struct regulator_ops vexpress_regulator_ops_ro = {
+	.get_voltage = vexpress_regulator_get_voltage,
+};
+
+static struct regulator_ops vexpress_regulator_ops = {
+	.get_voltage = vexpress_regulator_get_voltage,
+	.set_voltage = vexpress_regulator_set_voltage,
+};
+
+static int vexpress_regulator_probe(struct platform_device *pdev)
+{
+	int err;
+	struct vexpress_regulator *reg;
+	struct regulator_init_data *init_data;
+	struct regulator_config config = { };
+
+	reg = devm_kzalloc(&pdev->dev, sizeof(*reg), GFP_KERNEL);
+	if (!reg) {
+		err = -ENOMEM;
+		goto error_kzalloc;
+	}
+
+	reg->func = vexpress_config_func_get_by_dev(&pdev->dev);
+	if (!reg->func) {
+		err = -ENXIO;
+		goto error_get_func;
+	}
+
+	reg->desc.name = dev_name(&pdev->dev);
+	reg->desc.type = REGULATOR_VOLTAGE;
+	reg->desc.owner = THIS_MODULE;
+	reg->desc.continuous_voltage_range = true;
+
+	init_data = of_get_regulator_init_data(&pdev->dev, pdev->dev.of_node);
+	if (!init_data) {
+		err = -EINVAL;
+		goto error_get_regulator_init_data;
+	}
+
+	init_data->constraints.apply_uV = 0;
+	if (init_data->constraints.min_uV && init_data->constraints.max_uV)
+		reg->desc.ops = &vexpress_regulator_ops;
+	else
+		reg->desc.ops = &vexpress_regulator_ops_ro;
+
+	config.dev = &pdev->dev;
+	config.init_data = init_data;
+	config.driver_data = reg;
+	config.of_node = pdev->dev.of_node;
+
+	reg->regdev = regulator_register(&reg->desc, &config);
+	if (IS_ERR(reg->regdev)) {
+		err = PTR_ERR(reg->regdev);
+		goto error_regulator_register;
+	}
+
+	platform_set_drvdata(pdev, reg);
+
+	return 0;
+
+error_regulator_register:
+error_get_regulator_init_data:
+	vexpress_config_func_put(reg->func);
+error_get_func:
+error_kzalloc:
+	return err;
+}
+
+static int __devexit vexpress_regulator_remove(struct platform_device *pdev)
+{
+	struct vexpress_regulator *reg = platform_get_drvdata(pdev);
+
+	vexpress_config_func_put(reg->func);
+	regulator_unregister(reg->regdev);
+
+	return 0;
+}
+
+static struct of_device_id vexpress_regulator_of_match[] = {
+	{ .compatible = "arm,vexpress-volt", },
+};
+
+static struct platform_driver vexpress_regulator_driver = {
+	.probe = vexpress_regulator_probe,
+	.remove = __devexit_p(vexpress_regulator_remove),
+	.driver	= {
+		.name = DRVNAME,
+		.owner = THIS_MODULE,
+		.of_match_table = vexpress_regulator_of_match,
+	},
+};
+
+module_platform_driver(vexpress_regulator_driver);
+
+MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");
+MODULE_DESCRIPTION("Versatile Express regulator");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:vexpress-regulator");