[PATCH v4 2/2] regulator: add device tree support for max8997

From: Thomas Abraham
Date: Sat Mar 24 2012 - 05:45:43 EST

Add device tree based discovery support for max8997.

Cc: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
Cc: Rajendra Nayak <rnayak@xxxxxx>
Cc: Rob Herring <rob.herring@xxxxxxxxxxx>
Cc: Grant Likely <grant.likely@xxxxxxxxxxxx>
Signed-off-by: Thomas Abraham <thomas.abraham@xxxxxxxxxx>
---
.../devicetree/bindings/regulator/max8997-pmic.txt | 133 ++++++++++++++++++
drivers/mfd/max8997.c | 73 ++++++++++-
drivers/regulator/max8997.c | 143 +++++++++++++++++++-
include/linux/mfd/max8997-private.h | 1 +
include/linux/mfd/max8997.h | 1 +
5 files changed, 347 insertions(+), 4 deletions(-)
create mode 100644 Documentation/devicetree/bindings/regulator/max8997-pmic.txt

diff --git a/Documentation/devicetree/bindings/regulator/max8997-pmic.txt b/Documentation/devicetree/bindings/regulator/max8997-pmic.txt
new file mode 100644
index 0000000..90a730b
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/max8997-pmic.txt
@@ -0,0 +1,133 @@
+* Maxim MAX8997 Voltage and Current Regulator
+
+The Maxim MAX8997 is a multi-function device which includes volatage and
+current regulators, rtc, charger controller and other sub-blocks. It is
+interfaced to the host controller using a i2c interface. Each sub-block is
+addressed by the host system using different i2c slave address. This document
+describes the bindings for 'pmic' sub-block of max8997.
+
+Required properties:
+- compatible: Should be "maxim,max8997-pmic".
+- reg: Specifies the i2c slave address of the pmic block. It should be 0x66.
+
+- max8997,pmic-buck1-dvs-voltage: A set of 8 voltage values in micro-volt (uV)
+ units for buck1 when changing voltage using gpio dvs. Refer to [1] below
+ for additional information.
+
+- max8997,pmic-buck2-dvs-voltage: A set of 8 voltage values in micro-volt (uV)
+ units for buck2 when changing voltage using gpio dvs. Refer to [1] below
+ for additional information.
+
+- max8997,pmic-buck5-dvs-voltage: A set of 8 voltage values in micro-volt (uV)
+ units for buck5 when changing voltage using gpio dvs. Refer to [1] below
+ for additional information.
+
+[1] If none of the 'max8997,pmic-buck[1/2/5]-uses-gpio-dvs' optional
+ property is specified, the 'max8997,pmic-buck[1/2/5]-dvs-voltage'
+ property should specify atleast one voltage level (which would be a
+ safe operating voltage).
+
+ If either of the 'max8997,pmic-buck[1/2/5]-uses-gpio-dvs' optional
+ property is specified, then all the eigth voltage values for the
+ 'max8997,pmic-buck[1/2/5]-dvs-voltage' should be specified.
+
+Optional properties:
+- interrupt-parent: Specifies the phandle of the interrupt controller to which
+ the interrupts from max8997 are delivered to.
+- interrupts: Interrupt specifiers for two interrupt sources.
+ - First interrupt specifier is for 'irq1' interrupt.
+ - Second interrupt specifier is for 'alert' interrupt.
+- max8997,pmic-buck1-uses-gpio-dvs: 'buck1' can be controlled by gpio dvs.
+- max8997,pmic-buck2-uses-gpio-dvs: 'buck2' can be controlled by gpio dvs.
+- max8997,pmic-buck5-uses-gpio-dvs: 'buck5' can be controlled by gpio dvs.
+
+Additional properties required if either of the optional properties are used:
+- max8997,pmic-ignore-gpiodvs-side-effect: When GPIO-DVS mode is used for
+ multiple bucks, changing the voltage value of one of the bucks may affect
+ that of another buck, which is the side effect of the change (set_voltage).
+ Use this property to ignore such side effects and change the voltage.
+
+- max8997,pmic-buck125-default-dvs-idx: Default voltage setting selected from
+ the possible 8 options selectable by the dvs gpios. The value of this
+ property should be between 0 and 7. If not specified or if out of range, the
+ default value of this property is set to 0.
+
+- max8997,pmic-buck125-dvs-gpios: GPIO specifiers for three host gpio's used
+ for dvs. The format of the gpio specifier depends in the gpio controller.
+
+
+Regulators: The regulators of max8997 that have to be instantiated should be
+included in a sub-node named 'regulators'. Regulator nodes included in this
+sub-node should be of the format as below. Note: The 'n' in LDOn and BUCKn
+represents the LDO or BUCK number as per the datasheet of max8997.
+
+ For LDO's:
+ LDOn {
+ standard regulator bindings here
+ };
+
+ For BUCK's:
+ BUCKn {
+ standard regulator bindings here
+ };
+
+The bindings inside the regulator nodes use the standard regulator bindings
+which are documented elsewhere.
+
+Example:
+
+ max8997_pmic@66 {
+ compatible = "maxim,max8997-pmic";
+ interrupt-parent = <&wakeup_eint>;
+ reg = <0x66>;
+ interrupts = <4 0>, <3 0>;
+
+ max8997,pmic-buck1-uses-gpio-dvs;
+ max8997,pmic-buck2-uses-gpio-dvs;
+ max8997,pmic-buck5-uses-gpio-dvs;
+
+ max8997,pmic-ignore-gpiodvs-side-effect;
+ max8997,pmic-buck125-default-dvs-idx = <0>;
+
+ max8997,pmic-buck125-dvs-gpios = <&gpx0 0 1 0 0>, /* SET1 */
+ <&gpx0 1 1 0 0>, /* SET2 */
+ <&gpx0 2 1 0 0>; /* SET3 */
+
+ max8997,pmic-buck1-dvs-voltage = <1350000>, <1300000>,
+ <1250000>, <1200000>,
+ <1150000>, <1100000>,
+ <1000000>, <950000>;
+
+ max8997,pmic-buck2-dvs-voltage = <1100000>, <1100000>,
+ <1100000>, <1100000>,
+ <1000000>, <1000000>,
+ <1000000>, <1000000>;
+
+ max8997,pmic-buck5-dvs-voltage = <1200000>, <1200000>,
+ <1200000>, <1200000>,
+ <1200000>, <1200000>,
+ <1200000>, <1200000>;
+
+ regulators {
+ ldo1_reg: LDO1 {
+ regulator-name = "VDD_ABB_3.3V";
+ regulator-min-microvolt = <3300000>;
+ regulator-max-microvolt = <3300000>;
+ };
+
+ ldo2_reg: LDO2 {
+ regulator-name = "VDD_ALIVE_1.1V";
+ regulator-min-microvolt = <1100000>;
+ regulator-max-microvolt = <1100000>;
+ regulator-always-on;
+ };
+
+ buck1_reg: BUCK1 {
+ regulator-name = "VDD_ARM_1.2V";
+ regulator-min-microvolt = <950000>;
+ regulator-max-microvolt = <1350000>;
+ regulator-always-on;
+ regulator-boot-on;
+ };
+ };
+ };
diff --git a/drivers/mfd/max8997.c b/drivers/mfd/max8997.c
index 20ecad3..1c38e98 100644
--- a/drivers/mfd/max8997.c
+++ b/drivers/mfd/max8997.c
@@ -21,8 +21,10 @@
* This driver is based on max8998.c
*/

+#include <linux/err.h>
#include <linux/slab.h>
#include <linux/i2c.h>
+#include <linux/of_irq.h>
#include <linux/interrupt.h>
#include <linux/pm_runtime.h>
#include <linux/module.h>
@@ -47,6 +49,13 @@ static struct mfd_cell max8997_devs[] = {
{ .name = "max8997-led", .id = 2 },
};

+#ifdef CONFIG_OF
+static struct of_device_id __devinitdata max8997_pmic_dt_match[] = {
+ { .compatible = "maxim,max8997-pmic", .data = TYPE_MAX8997 },
+ {},
+};
+#endif
+
int max8997_read_reg(struct i2c_client *i2c, u8 reg, u8 *dest)
{
struct max8997_dev *max8997 = i2c_get_clientdata(i2c);
@@ -123,6 +132,58 @@ int max8997_update_reg(struct i2c_client *i2c, u8 reg, u8 val, u8 mask)
}
EXPORT_SYMBOL_GPL(max8997_update_reg);

+#ifdef CONFIG_OF
+/*
+ * Only the common platform data elements for max8997 are parsed here from the
+ * device tree. Other sub-modules of max8997 such as pmic, rtc and others have
+ * to parse their own platform data elements from device tree.
+ *
+ * The max8997 platform data structure is instantiated here and the drivers for
+ * the sub-modules need not instantiate another instance while parsing their
+ * platform data.
+ */
+static struct max8997_platform_data *max8997_i2c_parse_dt_pdata(
+ struct device *dev)
+{
+ struct max8997_platform_data *pd;
+
+ pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+ if (!pd) {
+ dev_err(dev, "could not allocate memory for pdata\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ pd->ono = irq_of_parse_and_map(dev->of_node, 1);
+
+ /*
+ * ToDo: the 'wakeup' member in the platform data is more of a linux
+ * specfic information. Hence, there is no binding for that yet and
+ * not parsed here.
+ */
+
+ return pd;
+}
+#else
+static int max8997_i2c_parse_dt_pdata(struct device *dev,
+ struct max8997_platform_data **pdata)
+{
+ return 0;
+}
+#endif
+
+static inline int max8997_i2c_get_driver_data(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+#ifdef CONFIG_OF
+ if (i2c->dev.of_node) {
+ const struct of_device_id *match;
+ match = of_match_node(max8997_pmic_dt_match, i2c->dev.of_node);
+ return (int)match->data;
+ }
+#endif
+ return (int)id->driver_data;
+}
+
static int max8997_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
@@ -137,12 +198,21 @@ static int max8997_i2c_probe(struct i2c_client *i2c,
i2c_set_clientdata(i2c, max8997);
max8997->dev = &i2c->dev;
max8997->i2c = i2c;
- max8997->type = id->driver_data;
+ max8997->type = max8997_i2c_get_driver_data(i2c, id);
max8997->irq = i2c->irq;

+ if (max8997->dev->of_node) {
+ pdata = max8997_i2c_parse_dt_pdata(max8997->dev);
+ if (IS_ERR(pdata)) {
+ ret = PTR_ERR(pdata);
+ goto err;
+ }
+ }
+
if (!pdata)
goto err;

+ max8997->pdata = pdata;
max8997->ono = pdata->ono;

mutex_init(&max8997->iolock);
@@ -434,6 +504,7 @@ static struct i2c_driver max8997_i2c_driver = {
.name = "max8997",
.owner = THIS_MODULE,
.pm = &max8997_pm,
+ .of_match_table = of_match_ptr(max8997_pmic_dt_match),
},
.probe = max8997_i2c_probe,
.remove = max8997_i2c_remove,
diff --git a/drivers/regulator/max8997.c b/drivers/regulator/max8997.c
index 9657929..dce8aaf 100644
--- a/drivers/regulator/max8997.c
+++ b/drivers/regulator/max8997.c
@@ -25,6 +25,7 @@
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio.h>
+#include <linux/of_gpio.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/platform_device.h>
@@ -32,6 +33,7 @@
#include <linux/regulator/machine.h>
#include <linux/mfd/max8997.h>
#include <linux/mfd/max8997-private.h>
+#include <linux/regulator/of_regulator.h>

struct max8997_data {
struct device *dev;
@@ -953,21 +955,155 @@ static struct regulator_desc regulators[] = {
},
};

+#ifdef CONFIG_OF
+static int max8997_pmic_dt_parse_dvs_gpio(struct max8997_dev *iodev,
+ struct max8997_platform_data *pdata,
+ struct device_node *pmic_np)
+{
+ int i, gpio;
+
+ for (i = 0; i < 3; i++) {
+ gpio = of_get_named_gpio(pmic_np,
+ "max8997,pmic-buck125-dvs-gpios", i);
+ if (!gpio_is_valid(gpio)) {
+ dev_err(iodev->dev, "invalid gpio[%d]: %d\n", i, gpio);
+ return -EINVAL;
+ }
+ pdata->buck125_gpios[i] = gpio;
+ }
+ return 0;
+}
+
+static int max8997_pmic_dt_parse_pdata(struct max8997_dev *iodev,
+ struct max8997_platform_data *pdata)
+{
+ struct device_node *pmic_np, *regulators_np, *reg_np;
+ struct max8997_regulator_data *rdata;
+ unsigned int i, dvs_voltage_nr = 1, ret;
+
+ pmic_np = iodev->dev->of_node;
+ if (!pmic_np) {
+ dev_err(iodev->dev, "could not find pmic sub-node\n");
+ return -ENODEV;
+ }
+
+ regulators_np = of_find_node_by_name(pmic_np, "regulators");
+ if (!regulators_np) {
+ dev_err(iodev->dev, "could not find regulators sub-node\n");
+ return -EINVAL;
+ }
+
+ /* count the number of regulators to be supported in pmic */
+ pdata->num_regulators = 0;
+ for_each_child_of_node(regulators_np, reg_np)
+ pdata->num_regulators++;
+
+ rdata = devm_kzalloc(iodev->dev, sizeof(*rdata) *
+ pdata->num_regulators, GFP_KERNEL);
+ if (!rdata) {
+ dev_err(iodev->dev, "could not allocate memory for "
+ "regulator data\n");
+ return -ENOMEM;
+ }
+
+ pdata->regulators = rdata;
+ for_each_child_of_node(regulators_np, reg_np) {
+ for (i = 0; i < ARRAY_SIZE(regulators); i++)
+ if (!of_node_cmp(reg_np->name, regulators[i].name))
+ break;
+ rdata->id = i;
+ rdata->initdata = of_get_regulator_init_data(
+ iodev->dev, reg_np);
+ rdata->reg_node = reg_np;
+ rdata++;
+ }
+
+ if (of_get_property(pmic_np, "max8997,pmic-buck1-uses-gpio-dvs", NULL))
+ pdata->buck1_gpiodvs = true;
+
+ if (of_get_property(pmic_np, "max8997,pmic-buck2-uses-gpio-dvs", NULL))
+ pdata->buck2_gpiodvs = true;
+
+ if (of_get_property(pmic_np, "max8997,pmic-buck5-uses-gpio-dvs", NULL))
+ pdata->buck5_gpiodvs = true;
+
+ if (pdata->buck1_gpiodvs || pdata->buck2_gpiodvs ||
+ pdata->buck5_gpiodvs) {
+ ret = max8997_pmic_dt_parse_dvs_gpio(iodev, pdata, pmic_np);
+ if (ret)
+ return -EINVAL;
+
+ if (of_property_read_u32(pmic_np,
+ "max8997,pmic-buck125-default-dvs-idx",
+ &pdata->buck125_default_idx)) {
+ pdata->buck125_default_idx = 0;
+ } else {
+ if (pdata->buck125_default_idx >= 8) {
+ pdata->buck125_default_idx = 0;
+ dev_info(iodev->dev, "invalid value for "
+ "default dvs index, using 0 instead\n");
+ }
+ }
+
+ if (of_get_property(pmic_np,
+ "max8997,pmic-ignore-gpiodvs-side-effect", NULL))
+ pdata->ignore_gpiodvs_side_effect = true;
+
+ dvs_voltage_nr = 8;
+ }
+
+ if (of_property_read_u32_array(pmic_np,
+ "max8997,pmic-buck1-dvs-voltage",
+ pdata->buck1_voltage, dvs_voltage_nr)) {
+ dev_err(iodev->dev, "buck1 voltages not specified\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32_array(pmic_np,
+ "max8997,pmic-buck2-dvs-voltage",
+ pdata->buck2_voltage, dvs_voltage_nr)) {
+ dev_err(iodev->dev, "buck2 voltages not specified\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32_array(pmic_np,
+ "max8997,pmic-buck5-dvs-voltage",
+ pdata->buck5_voltage, dvs_voltage_nr)) {
+ dev_err(iodev->dev, "buck5 voltages not specified\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+#else
+static int max8997_pmic_dt_parse_pdata(struct max8997_dev *iodev,
+ struct max8997_platform_data *pdata)
+{
+ return 0;
+}
+#endif /* CONFIG_OF */
+
static __devinit int max8997_pmic_probe(struct platform_device *pdev)
{
struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
- struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
+ struct max8997_platform_data *pdata = iodev->pdata;
struct regulator_dev **rdev;
struct max8997_data *max8997;
struct i2c_client *i2c;
int i, ret, size;
u8 max_buck1 = 0, max_buck2 = 0, max_buck5 = 0;

- if (!pdata) {
+ if (IS_ERR_OR_NULL(pdata)) {
dev_err(pdev->dev.parent, "No platform init data supplied.\n");
return -ENODEV;
}

+ if (iodev->dev->of_node) {
+ ret = max8997_pmic_dt_parse_pdata(iodev, pdata);
+ if (ret)
+ return ret;
+ }
+
max8997 = kzalloc(sizeof(struct max8997_data), GFP_KERNEL);
if (!max8997)
return -ENOMEM;
@@ -1141,7 +1277,8 @@ static __devinit int max8997_pmic_probe(struct platform_device *pdev)
regulators[id].n_voltages = 16;

rdev[i] = regulator_register(&regulators[id], max8997->dev,
- pdata->regulators[i].initdata, max8997, NULL);
+ pdata->regulators[i].initdata, max8997,
+ pdata->regulators[i].reg_node);
if (IS_ERR(rdev[i])) {
ret = PTR_ERR(rdev[i]);
dev_err(max8997->dev, "regulator init failed for %d\n",
diff --git a/include/linux/mfd/max8997-private.h b/include/linux/mfd/max8997-private.h
index 830152c..6ae21bf 100644
--- a/include/linux/mfd/max8997-private.h
+++ b/include/linux/mfd/max8997-private.h
@@ -316,6 +316,7 @@ enum max8997_irq {
#define MAX8997_NUM_GPIO 12
struct max8997_dev {
struct device *dev;
+ struct max8997_platform_data *pdata;
struct i2c_client *i2c; /* 0xcc / PMIC, Battery Control, and FLASH */
struct i2c_client *rtc; /* slave addr 0x0c */
struct i2c_client *haptic; /* slave addr 0x90 */
diff --git a/include/linux/mfd/max8997.h b/include/linux/mfd/max8997.h
index 818486c..ba92375 100644
--- a/include/linux/mfd/max8997.h
+++ b/include/linux/mfd/max8997.h
@@ -75,6 +75,7 @@ enum max8998_regulators {
struct max8997_regulator_data {
int id;
struct regulator_init_data *initdata;
+ struct device_node *reg_node;
};

enum max8997_muic_usb_type {
--
1.6.6.rc2

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