Re: [PATCH 01/01] regulator: support max8649

Re: [PATCH 01/01] regulator: support max8649

[Mark Brown]

On Tue, Jan 12, 2010 at 03:51:09AM -0500, Haojian Zhuang wrote:

> Enable Maxim max8649 regulator driver.

This seems basically fine but there's a few relatively minor issues
below, mostly coding style rather than anything serious.

> +static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
> +{
> +	return MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP;
> +}

Brackets here would help legibility even if not strictly required.

> +	data= (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
> +		/ MAX8649_DCDC_STEP;

Should be "data ="

> +static struct regulator_desc dcdc_desc = {
> +	.name		= "DCDC",

MAX8649 might be a better name but it doesn't really make any odds.

> +	.ops		= &max8649_dcdc_ops,
> +	.type		= REGULATOR_VOLTAGE,
> +	.n_voltages	= 1 << 7,

Use the max index value you have above?

> +	info->vol_reg = (info->mode == 0) ? MAX8649_MODE0
> +			: ((info->mode == 1) ? MAX8649_MODE1
> +			: ((info->mode == 2) ? MAX8649_MODE2
> +			: MAX8649_MODE3));

This should really be a switch statement for legibility.  In general the
ternery operator should be used very sparingly, and if you've got more
than one of them it's not a good sign.

> +	/* enable/disable auto enter power save mode */
> +	info->powersave = pdata->powersave;
> +	data = (info->powersave) ? 0 : MAX8649_POWER_SAVE;
> +	max8649_set_bits(info->i2c, info->vol_reg, MAX8649_POWER_SAVE, data);

I'm not sure what this power save mode is but I suspect it'd map well
onto the regulator_set_mode() API - normal mode for power saving, fast
mode for power saving disabled.

> +	if (pdata->ramp_timing) {
> +		info->ramp_timing = pdata->ramp_timing;
> +		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
> +				 info->ramp_timing << 5);
> +	}

You might want to implement the new enable_time() API for this.

> +	pr_info("Max8649 regulator device is detected.\n");

This should be at most debug level, and should be dev_() to distinguish
between multiple devices.

Re: [PATCH 01/01] regulator: support max8649

[Haojian Zhuang]

[-- Attachment #1: Type: text/plain, Size: 975 bytes --]

On Tue, Jan 12, 2010 at 6:51 AM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> On Tue, Jan 12, 2010 at 03:51:09AM -0500, Haojian Zhuang wrote:
>
>> Enable Maxim max8649 regulator driver.
>
> This seems basically fine but there's a few relatively minor issues
> below, mostly coding style rather than anything serious.
>
>
>> +     if (pdata->ramp_timing) {
>> +             info->ramp_timing = pdata->ramp_timing;
>> +             max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
>> +                              info->ramp_timing << 5);
>> +     }
>
> You might want to implement the new enable_time() API for this.
>

This ramp timing is the time interval of each step on adjusting
voltage. I just want to control the timing in initialization.
enable_time() is only called before enabling regulator. And I don't
understand what would be done in enable_time().

Others are updated in this attached patch.

Thanks
Haojian

[-- Attachment #2: 0001-regulator-enable-max8649-regulator-driver.patch --]
[-- Type: text/x-patch, Size: 13016 bytes --]

From 97daf5dcac5073bdb915eca0c39eceb2e74e787f Mon Sep 17 00:00:00 2001
From: Haojian Zhuang <haojian.zhuang@marvell.com>
Date: Mon, 25 Jan 2010 10:24:09 -0500
Subject: [PATCH] regulator: enable max8649 regulator driver

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
---
 drivers/regulator/Kconfig         |    7 +
 drivers/regulator/Makefile        |    1 +
 drivers/regulator/max8649.c       |  385 +++++++++++++++++++++++++++++++++++++
 include/linux/regulator/max8649.h |   44 +++++
 4 files changed, 437 insertions(+), 0 deletions(-)
 create mode 100644 drivers/regulator/max8649.c
 create mode 100644 include/linux/regulator/max8649.h

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 262f62e..a6e7a0c 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -69,6 +69,13 @@ config REGULATOR_MAX1586
 	  regulator via I2C bus. The provided regulator is suitable
 	  for PXA27x chips to control VCC_CORE and VCC_USIM voltages.
 
+config REGULATOR_MAX8649
+	tristate "Maxim 8649 voltage regulator"
+	depends on I2C
+	help
+	  This driver controls a Maxim 8649 voltage output regulator via
+	  I2C bus.
+
 config REGULATOR_MAX8660
 	tristate "Maxim 8660/8661 voltage regulator"
 	depends on I2C
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b3c806c..075835b 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o
 obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o
 obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o
+obj-$(CONFIG_REGULATOR_MAX8649)	+= max8649.o
 obj-$(CONFIG_REGULATOR_MAX8660) += max8660.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o
diff --git a/drivers/regulator/max8649.c b/drivers/regulator/max8649.c
new file mode 100644
index 0000000..a83e882
--- /dev/null
+++ b/drivers/regulator/max8649.c
@@ -0,0 +1,385 @@
+/*
+ * Regulators driver for Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/max8649.h>
+
+#define MAX8649_DCDC_VMIN	750000		/* uV */
+#define MAX8649_DCDC_VMAX	1380000		/* uV */
+#define MAX8649_DCDC_STEP	10000		/* uV */
+#define MAX8649_VOL_MASK	0x3f
+
+/* Registers */
+#define MAX8649_MODE0		0x00
+#define MAX8649_MODE1		0x01
+#define MAX8649_MODE2		0x02
+#define MAX8649_MODE3		0x03
+#define MAX8649_CONTROL		0x04
+#define MAX8649_SYNC		0x05
+#define MAX8649_RAMP		0x06
+#define MAX8649_CHIP_ID1	0x08
+#define MAX8649_CHIP_ID2	0x09
+
+/* Bits */
+#define MAX8649_EN_PD		(1 << 7)
+#define MAX8649_VID0_PD		(1 << 6)
+#define MAX8649_VID1_PD		(1 << 5)
+#define MAX8649_VID_MASK	(3 << 5)
+
+#define MAX8649_FORCE_PWM	(1 << 7)
+#define MAX8649_SYNC_EXTCLK	(1 << 6)
+
+#define MAX8649_EXT_MASK	(3 << 6)
+
+#define MAX8649_RAMP_MASK	(7 << 5)
+#define MAX8649_RAMP_DOWN	(1 << 1)
+
+struct max8649_regulator_info {
+	struct regulator_dev	*regulator;
+	struct i2c_client	*i2c;
+	struct device		*dev;
+	struct mutex		io_lock;
+
+	int		vol_reg;
+	unsigned	mode:2;	/* bit[1:0] = VID1, VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+/* I2C operations */
+
+static inline int max8649_read_device(struct i2c_client *i2c,
+				      int reg, int bytes, void *dest)
+{
+	unsigned char data;
+	int ret;
+
+	data = (unsigned char)reg;
+	ret = i2c_master_send(i2c, &data, 1);
+	if (ret < 0)
+		return ret;
+	ret = i2c_master_recv(i2c, dest, bytes);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static inline int max8649_write_device(struct i2c_client *i2c,
+				       int reg, int bytes, void *src)
+{
+	unsigned char buf[bytes + 1];
+	int ret;
+
+	buf[0] = (unsigned char)reg;
+	memcpy(&buf[1], src, bytes);
+
+	ret = i2c_master_send(i2c, buf, bytes + 1);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static int max8649_reg_read(struct i2c_client *i2c, int reg)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char data;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &data);
+	mutex_unlock(&info->io_lock);
+
+	if (ret < 0)
+		return ret;
+	return (int)data;
+}
+
+static int max8649_set_bits(struct i2c_client *i2c, int reg,
+			    unsigned char mask, unsigned char data)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char value;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &value);
+	if (ret < 0)
+		goto out;
+	value &= ~mask;
+	value |= data;
+	ret = max8649_write_device(i2c, reg, 1, &value);
+out:
+	mutex_unlock(&info->io_lock);
+	return ret;
+}
+
+static inline int check_range(int min_uV, int max_uV)
+{
+	if ((min_uV < MAX8649_DCDC_VMIN) || (max_uV > MAX8649_DCDC_VMAX)
+		|| (min_uV > max_uV))
+		return -EINVAL;
+	return 0;
+}
+
+static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
+{
+	return (MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP);
+}
+
+static int max8649_get_voltage(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data;
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret < 0)
+		return ret;
+	data = (unsigned char)ret & MAX8649_VOL_MASK;
+	return (max8649_list_voltage(rdev, data));
+}
+
+static int max8649_set_voltage(struct regulator_dev *rdev,
+			       int min_uV, int max_uV)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data, mask;
+
+	if (check_range(min_uV, max_uV)) {
+		dev_err(info->dev, "invalid voltage range (%d, %d) uV\n",
+			min_uV, max_uV);
+		return -EINVAL;
+	}
+	data = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
+		/ MAX8649_DCDC_STEP;
+	mask = MAX8649_VOL_MASK;
+
+	return max8649_set_bits(info->i2c, info->vol_reg, mask, data);
+}
+
+/* EN_PD means pulldown on EN input */
+static int max8649_enable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD, 0);
+}
+
+/*
+ * Applied internal pulldown resistor on EN input pin.
+ * If pulldown EN pin outside, it would be better.
+ */
+static int max8649_disable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD,
+				MAX8649_EN_PD);
+}
+
+static int max8649_is_enabled(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CONTROL);
+	if (ret < 0)
+		return ret;
+	return !((unsigned char)ret & MAX8649_EN_PD);
+}
+
+static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+	case REGULATOR_MODE_NORMAL:
+		max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
+				 MAX8649_FORCE_PWM);
+		break;
+	case REGULATOR_MODE_IDLE:
+	case REGULATOR_MODE_STANDBY:
+		max8649_set_bits(info->i2c, info->vol_reg,
+				 MAX8649_FORCE_PWM, 0);
+		break;
+	}
+	return 0;
+}
+
+static unsigned int max8649_get_mode(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret & MAX8649_FORCE_PWM)
+		return REGULATOR_MODE_NORMAL;
+	return REGULATOR_MODE_IDLE;
+}
+
+static struct regulator_ops max8649_dcdc_ops = {
+	.set_voltage	= max8649_set_voltage,
+	.get_voltage	= max8649_get_voltage,
+	.list_voltage	= max8649_list_voltage,
+	.enable		= max8649_enable,
+	.disable	= max8649_disable,
+	.is_enabled	= max8649_is_enabled,
+	.set_mode	= max8649_set_mode,
+	.get_mode	= max8649_get_mode,
+
+};
+
+static struct regulator_desc dcdc_desc = {
+	.name		= "max8649",
+	.ops		= &max8649_dcdc_ops,
+	.type		= REGULATOR_VOLTAGE,
+	.n_voltages	= 1 << 6,
+	.owner		= THIS_MODULE,
+};
+
+static int __devinit max8649_regulator_probe(struct i2c_client *client,
+					     const struct i2c_device_id *id)
+{
+	struct max8649_platform_data *pdata = client->dev.platform_data;
+	struct max8649_regulator_info *info = NULL;
+	unsigned char data;
+	int ret;
+
+	info = kzalloc(sizeof(struct max8649_regulator_info), GFP_KERNEL);
+	if (!info) {
+		dev_err(&client->dev, "No enough memory\n");
+		return -ENOMEM;
+	}
+
+	info->i2c = client;
+	info->dev = &client->dev;
+	mutex_init(&info->io_lock);
+	i2c_set_clientdata(client, info);
+
+	info->mode = pdata->mode;
+	switch (info->mode) {
+	case 0:
+		info->vol_reg = MAX8649_MODE0;
+		break;
+	case 1:
+		info->vol_reg = MAX8649_MODE1;
+		break;
+	case 2:
+		info->vol_reg = MAX8649_MODE2;
+		break;
+	case 3:
+		info->vol_reg = MAX8649_MODE3;
+		break;
+	default:
+		break;
+	}
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CHIP_ID1);
+	if (ret < 0) {
+		dev_err(info->dev, "Failed to detect ID of MAX8649:%d\n",
+			ret);
+		goto out;
+	}
+	dev_info(info->dev, "Detected MAX8649 (ID:%x)\n", ret);
+
+	/* enable VID0 & VID1 */
+	max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
+
+	/* enable/disable external clock synchronization */
+	info->extclk = pdata->extclk;
+	data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
+	max8649_set_bits(info->i2c, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
+	if (info->extclk) {
+		/* set external clock frequency */
+		info->extclk_freq = pdata->extclk_freq;
+		max8649_set_bits(info->i2c, MAX8649_SYNC, MAX8649_EXT_MASK,
+				 info->extclk_freq);
+	}
+
+	if (pdata->ramp_timing) {
+		info->ramp_timing = pdata->ramp_timing;
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
+				 info->ramp_timing << 5);
+	}
+
+	info->ramp_down = pdata->ramp_down;
+	if (info->ramp_down) {
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_DOWN,
+				 MAX8649_RAMP_DOWN);
+	}
+
+	info->regulator = regulator_register(&dcdc_desc, &client->dev,
+					     pdata->regulator, info);
+	if (IS_ERR(info->regulator)) {
+		dev_err(info->dev, "failed to register regulator %s\n",
+			dcdc_desc.name);
+		ret = PTR_ERR(info->regulator);
+		goto out;
+	}
+
+	dev_info(info->dev, "Max8649 regulator device is detected.\n");
+	return 0;
+out:
+	kfree(info);
+	return ret;
+}
+
+static int __devexit max8649_regulator_remove(struct i2c_client *client)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(client);
+
+	if (info) {
+		if (info->regulator)
+			regulator_unregister(info->regulator);
+		kfree(info);
+	}
+	i2c_set_clientdata(client, NULL);
+
+	return 0;
+}
+
+static const struct i2c_device_id max8649_id[] = {
+	{ "max8649", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max8649_id);
+
+static struct i2c_driver max8649_driver = {
+	.probe		= max8649_regulator_probe,
+	.remove		= __devexit_p(max8649_regulator_remove),
+	.driver		= {
+		.name	= "max8649",
+	},
+	.id_table	= max8649_id,
+};
+
+static int __init max8649_init(void)
+{
+	return i2c_add_driver(&max8649_driver);
+}
+subsys_initcall(max8649_init);
+
+static void __exit max8649_exit(void)
+{
+	i2c_del_driver(&max8649_driver);
+}
+module_exit(max8649_exit);
+
+/* Module information */
+MODULE_DESCRIPTION("MAXIM 8649 voltage regulator driver");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");
+
diff --git a/include/linux/regulator/max8649.h b/include/linux/regulator/max8649.h
new file mode 100644
index 0000000..417d14e
--- /dev/null
+++ b/include/linux/regulator/max8649.h
@@ -0,0 +1,44 @@
+/*
+ * Interface of Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+
+#ifndef __LINUX_REGULATOR_MAX8649_H
+#define	__LINUX_REGULATOR_MAX8649_H
+
+#include <linux/regulator/machine.h>
+
+enum {
+	MAX8649_EXTCLK_26MHZ = 0,
+	MAX8649_EXTCLK_13MHZ,
+	MAX8649_EXTCLK_19MHZ,	/* 19.2MHz */
+};
+
+enum {
+	MAX8649_RAMP_32MV = 0,
+	MAX8649_RAMP_16MV,
+	MAX8649_RAMP_8MV,
+	MAX8649_RAMP_4MV,
+	MAX8649_RAMP_2MV,
+	MAX8649_RAMP_1MV,
+	MAX8649_RAMP_0_5MV,
+	MAX8649_RAMP_0_25MV,
+};
+
+struct max8649_platform_data {
+	struct regulator_init_data *regulator;
+
+	unsigned	mode:2;		/* bit[1:0] = VID1,VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+#endif	/* __LINUX_REGULATOR_MAX8649_H */
-- 
1.5.6.5

Re: [PATCH 01/01] regulator: support max8649

[Mark Brown]

On Mon, Jan 25, 2010 at 06:01:41AM -0500, Haojian Zhuang wrote:
> On Tue, Jan 12, 2010 at 6:51 AM, Mark Brown

> >> +     if (pdata->ramp_timing) {
> >> +             info->ramp_timing = pdata->ramp_timing;
> >> +             max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
> >> +                              info->ramp_timing << 5);
> >> +     }

> > You might want to implement the new enable_time() API for this.

> This ramp timing is the time interval of each step on adjusting
> voltage. I just want to control the timing in initialization.

If this applies to any voltage change at all then rather than just power
on I need to finish off the stuff I've been sitting on for handling slew
times for voltage changes.  If the regulator hasn't yet reached the
requested output when the consumer tries using it the consumer might get
broken.

If the ramp also gets applied when initially turning on the regulator
you'd still want to implement enable_time() for the same reason.

> enable_time() is only called before enabling regulator. And I don't
> understand what would be done in enable_time().

You'd return the amount of time taken to turn on the regulator and get
the output voltage stable in the current configuration.  This will then
be used by the core to ensure that the consumer only tries to use the
regulator once it's fully enabled.

> +static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
> +{
> +	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
> +
> +	switch (mode) {
> +	case REGULATOR_MODE_FAST:
> +	case REGULATOR_MODE_NORMAL:
> +		max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
> +				 MAX8649_FORCE_PWM);
> +		break;

Are you sure about this?  I'd expect to see force PWM used only for
_FAST, for _NORMAL pulse skipping is usually desired behaviour.

> +	case REGULATOR_MODE_IDLE:
> +	case REGULATOR_MODE_STANDBY:
> +		max8649_set_bits(info->i2c, info->vol_reg,
> +				 MAX8649_FORCE_PWM, 0);

I'd just leave these unimplemented (there's no need to support all
modes) and make sure that this ties in with...

> +static unsigned int max8649_get_mode(struct regulator_dev *rdev)
> +{
> +	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
> +	int ret;
> +
> +	ret = max8649_reg_read(info->i2c, info->vol_reg);
> +	if (ret & MAX8649_FORCE_PWM)
> +		return REGULATOR_MODE_NORMAL;
> +	return REGULATOR_MODE_IDLE;

...this.

Re: [PATCH 01/01] regulator: support max8649

[Haojian Zhuang]

[-- Attachment #1: Type: text/plain, Size: 2835 bytes --]

On Mon, Jan 25, 2010 at 8:56 AM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> On Mon, Jan 25, 2010 at 06:01:41AM -0500, Haojian Zhuang wrote:
>> On Tue, Jan 12, 2010 at 6:51 AM, Mark Brown
>
>> >> +     if (pdata->ramp_timing) {
>> >> +             info->ramp_timing = pdata->ramp_timing;
>> >> +             max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
>> >> +                              info->ramp_timing << 5);
>> >> +     }
>
>> > You might want to implement the new enable_time() API for this.
>
>> This ramp timing is the time interval of each step on adjusting
>> voltage. I just want to control the timing in initialization.
>
> If this applies to any voltage change at all then rather than just power
> on I need to finish off the stuff I've been sitting on for handling slew
> times for voltage changes.  If the regulator hasn't yet reached the
> requested output when the consumer tries using it the consumer might get
> broken.
>
> If the ramp also gets applied when initially turning on the regulator
> you'd still want to implement enable_time() for the same reason.
>
>> enable_time() is only called before enabling regulator. And I don't
>> understand what would be done in enable_time().
>
> You'd return the amount of time taken to turn on the regulator and get
> the output voltage stable in the current configuration.  This will then
> be used by the core to ensure that the consumer only tries to use the
> regulator once it's fully enabled.
>
>> +static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
>> +{
>> +     struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
>> +
>> +     switch (mode) {
>> +     case REGULATOR_MODE_FAST:
>> +     case REGULATOR_MODE_NORMAL:
>> +             max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
>> +                              MAX8649_FORCE_PWM);
>> +             break;
>
> Are you sure about this?  I'd expect to see force PWM used only for
> _FAST, for _NORMAL pulse skipping is usually desired behaviour.
>
>> +     case REGULATOR_MODE_IDLE:
>> +     case REGULATOR_MODE_STANDBY:
>> +             max8649_set_bits(info->i2c, info->vol_reg,
>> +                              MAX8649_FORCE_PWM, 0);
>
> I'd just leave these unimplemented (there's no need to support all
> modes) and make sure that this ties in with...
>
>> +static unsigned int max8649_get_mode(struct regulator_dev *rdev)
>> +{
>> +     struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
>> +     int ret;
>> +
>> +     ret = max8649_reg_read(info->i2c, info->vol_reg);
>> +     if (ret & MAX8649_FORCE_PWM)
>> +             return REGULATOR_MODE_NORMAL;
>> +     return REGULATOR_MODE_IDLE;
>
> ...this.
>

update patch now.

Thanks
Haojian

[-- Attachment #2: 0001-regulator-enable-max8649-regulator-driver.patch --]
[-- Type: text/x-patch, Size: 13562 bytes --]

From 2b5a73c336d2b5dc48c8cf1f2a804b6968659f78 Mon Sep 17 00:00:00 2001
From: Haojian Zhuang <haojian.zhuang@marvell.com>
Date: Mon, 25 Jan 2010 10:24:09 -0500
Subject: [PATCH] regulator: enable max8649 regulator driver

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
---
 drivers/regulator/Kconfig         |    7 +
 drivers/regulator/Makefile        |    1 +
 drivers/regulator/max8649.c       |  406 +++++++++++++++++++++++++++++++++++++
 include/linux/regulator/max8649.h |   44 ++++
 4 files changed, 458 insertions(+), 0 deletions(-)
 create mode 100644 drivers/regulator/max8649.c
 create mode 100644 include/linux/regulator/max8649.h

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 262f62e..a6e7a0c 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -69,6 +69,13 @@ config REGULATOR_MAX1586
 	  regulator via I2C bus. The provided regulator is suitable
 	  for PXA27x chips to control VCC_CORE and VCC_USIM voltages.
 
+config REGULATOR_MAX8649
+	tristate "Maxim 8649 voltage regulator"
+	depends on I2C
+	help
+	  This driver controls a Maxim 8649 voltage output regulator via
+	  I2C bus.
+
 config REGULATOR_MAX8660
 	tristate "Maxim 8660/8661 voltage regulator"
 	depends on I2C
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b3c806c..075835b 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o
 obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o
 obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o
+obj-$(CONFIG_REGULATOR_MAX8649)	+= max8649.o
 obj-$(CONFIG_REGULATOR_MAX8660) += max8660.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o
diff --git a/drivers/regulator/max8649.c b/drivers/regulator/max8649.c
new file mode 100644
index 0000000..b5ffd89
--- /dev/null
+++ b/drivers/regulator/max8649.c
@@ -0,0 +1,406 @@
+/*
+ * Regulators driver for Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/max8649.h>
+
+#define MAX8649_DCDC_VMIN	750000		/* uV */
+#define MAX8649_DCDC_VMAX	1380000		/* uV */
+#define MAX8649_DCDC_STEP	10000		/* uV */
+#define MAX8649_VOL_MASK	0x3f
+
+/* Registers */
+#define MAX8649_MODE0		0x00
+#define MAX8649_MODE1		0x01
+#define MAX8649_MODE2		0x02
+#define MAX8649_MODE3		0x03
+#define MAX8649_CONTROL		0x04
+#define MAX8649_SYNC		0x05
+#define MAX8649_RAMP		0x06
+#define MAX8649_CHIP_ID1	0x08
+#define MAX8649_CHIP_ID2	0x09
+
+/* Bits */
+#define MAX8649_EN_PD		(1 << 7)
+#define MAX8649_VID0_PD		(1 << 6)
+#define MAX8649_VID1_PD		(1 << 5)
+#define MAX8649_VID_MASK	(3 << 5)
+
+#define MAX8649_FORCE_PWM	(1 << 7)
+#define MAX8649_SYNC_EXTCLK	(1 << 6)
+
+#define MAX8649_EXT_MASK	(3 << 6)
+
+#define MAX8649_RAMP_MASK	(7 << 5)
+#define MAX8649_RAMP_DOWN	(1 << 1)
+
+struct max8649_regulator_info {
+	struct regulator_dev	*regulator;
+	struct i2c_client	*i2c;
+	struct device		*dev;
+	struct mutex		io_lock;
+
+	int		vol_reg;
+	unsigned	mode:2;	/* bit[1:0] = VID1, VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+/* I2C operations */
+
+static inline int max8649_read_device(struct i2c_client *i2c,
+				      int reg, int bytes, void *dest)
+{
+	unsigned char data;
+	int ret;
+
+	data = (unsigned char)reg;
+	ret = i2c_master_send(i2c, &data, 1);
+	if (ret < 0)
+		return ret;
+	ret = i2c_master_recv(i2c, dest, bytes);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static inline int max8649_write_device(struct i2c_client *i2c,
+				       int reg, int bytes, void *src)
+{
+	unsigned char buf[bytes + 1];
+	int ret;
+
+	buf[0] = (unsigned char)reg;
+	memcpy(&buf[1], src, bytes);
+
+	ret = i2c_master_send(i2c, buf, bytes + 1);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static int max8649_reg_read(struct i2c_client *i2c, int reg)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char data;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &data);
+	mutex_unlock(&info->io_lock);
+
+	if (ret < 0)
+		return ret;
+	return (int)data;
+}
+
+static int max8649_set_bits(struct i2c_client *i2c, int reg,
+			    unsigned char mask, unsigned char data)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char value;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &value);
+	if (ret < 0)
+		goto out;
+	value &= ~mask;
+	value |= data;
+	ret = max8649_write_device(i2c, reg, 1, &value);
+out:
+	mutex_unlock(&info->io_lock);
+	return ret;
+}
+
+static inline int check_range(int min_uV, int max_uV)
+{
+	if ((min_uV < MAX8649_DCDC_VMIN) || (max_uV > MAX8649_DCDC_VMAX)
+		|| (min_uV > max_uV))
+		return -EINVAL;
+	return 0;
+}
+
+static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
+{
+	return (MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP);
+}
+
+static int max8649_get_voltage(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data;
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret < 0)
+		return ret;
+	data = (unsigned char)ret & MAX8649_VOL_MASK;
+	return (max8649_list_voltage(rdev, data));
+}
+
+static int max8649_set_voltage(struct regulator_dev *rdev,
+			       int min_uV, int max_uV)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data, mask;
+
+	if (check_range(min_uV, max_uV)) {
+		dev_err(info->dev, "invalid voltage range (%d, %d) uV\n",
+			min_uV, max_uV);
+		return -EINVAL;
+	}
+	data = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
+		/ MAX8649_DCDC_STEP;
+	mask = MAX8649_VOL_MASK;
+
+	return max8649_set_bits(info->i2c, info->vol_reg, mask, data);
+}
+
+/* EN_PD means pulldown on EN input */
+static int max8649_enable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD, 0);
+}
+
+/*
+ * Applied internal pulldown resistor on EN input pin.
+ * If pulldown EN pin outside, it would be better.
+ */
+static int max8649_disable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD,
+				MAX8649_EN_PD);
+}
+
+static int max8649_is_enabled(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CONTROL);
+	if (ret < 0)
+		return ret;
+	return !((unsigned char)ret & MAX8649_EN_PD);
+}
+
+static int max8649_enable_time(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int voltage, step, ret;
+
+	/* get voltage */
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret < 0)
+		return ret;
+	ret &= MAX8649_VOL_MASK;
+	voltage = max8649_list_voltage(rdev, (unsigned char)ret);	/* uV */
+
+	/* get step */
+	ret = max8649_reg_read(info->i2c, MAX8649_RAMP);
+	if (ret < 0)
+		return ret;
+	ret = (ret & MAX8649_RAMP_MASK) >> 5;
+	step = (32 * 1000) >> ret;	/* uV/uS */
+
+	return (voltage / step);
+}
+
+static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
+				 MAX8649_FORCE_PWM);
+		break;
+	case REGULATOR_MODE_NORMAL:
+		max8649_set_bits(info->i2c, info->vol_reg,
+				 MAX8649_FORCE_PWM, 0);
+		break;
+	}
+	return 0;
+}
+
+static unsigned int max8649_get_mode(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret & MAX8649_FORCE_PWM)
+		return REGULATOR_MODE_FAST;
+	return REGULATOR_MODE_NORMAL;
+}
+
+static struct regulator_ops max8649_dcdc_ops = {
+	.set_voltage	= max8649_set_voltage,
+	.get_voltage	= max8649_get_voltage,
+	.list_voltage	= max8649_list_voltage,
+	.enable		= max8649_enable,
+	.disable	= max8649_disable,
+	.is_enabled	= max8649_is_enabled,
+	.enable_time	= max8649_enable_time,
+	.set_mode	= max8649_set_mode,
+	.get_mode	= max8649_get_mode,
+
+};
+
+static struct regulator_desc dcdc_desc = {
+	.name		= "max8649",
+	.ops		= &max8649_dcdc_ops,
+	.type		= REGULATOR_VOLTAGE,
+	.n_voltages	= 1 << 6,
+	.owner		= THIS_MODULE,
+};
+
+static int __devinit max8649_regulator_probe(struct i2c_client *client,
+					     const struct i2c_device_id *id)
+{
+	struct max8649_platform_data *pdata = client->dev.platform_data;
+	struct max8649_regulator_info *info = NULL;
+	unsigned char data;
+	int ret;
+
+	info = kzalloc(sizeof(struct max8649_regulator_info), GFP_KERNEL);
+	if (!info) {
+		dev_err(&client->dev, "No enough memory\n");
+		return -ENOMEM;
+	}
+
+	info->i2c = client;
+	info->dev = &client->dev;
+	mutex_init(&info->io_lock);
+	i2c_set_clientdata(client, info);
+
+	info->mode = pdata->mode;
+	switch (info->mode) {
+	case 0:
+		info->vol_reg = MAX8649_MODE0;
+		break;
+	case 1:
+		info->vol_reg = MAX8649_MODE1;
+		break;
+	case 2:
+		info->vol_reg = MAX8649_MODE2;
+		break;
+	case 3:
+		info->vol_reg = MAX8649_MODE3;
+		break;
+	default:
+		break;
+	}
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CHIP_ID1);
+	if (ret < 0) {
+		dev_err(info->dev, "Failed to detect ID of MAX8649:%d\n",
+			ret);
+		goto out;
+	}
+	dev_info(info->dev, "Detected MAX8649 (ID:%x)\n", ret);
+
+	/* enable VID0 & VID1 */
+	max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
+
+	/* enable/disable external clock synchronization */
+	info->extclk = pdata->extclk;
+	data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
+	max8649_set_bits(info->i2c, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
+	if (info->extclk) {
+		/* set external clock frequency */
+		info->extclk_freq = pdata->extclk_freq;
+		max8649_set_bits(info->i2c, MAX8649_SYNC, MAX8649_EXT_MASK,
+				 info->extclk_freq);
+	}
+
+	if (pdata->ramp_timing) {
+		info->ramp_timing = pdata->ramp_timing;
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
+				 info->ramp_timing << 5);
+	}
+
+	info->ramp_down = pdata->ramp_down;
+	if (info->ramp_down) {
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_DOWN,
+				 MAX8649_RAMP_DOWN);
+	}
+
+	info->regulator = regulator_register(&dcdc_desc, &client->dev,
+					     pdata->regulator, info);
+	if (IS_ERR(info->regulator)) {
+		dev_err(info->dev, "failed to register regulator %s\n",
+			dcdc_desc.name);
+		ret = PTR_ERR(info->regulator);
+		goto out;
+	}
+
+	dev_info(info->dev, "Max8649 regulator device is detected.\n");
+	return 0;
+out:
+	kfree(info);
+	return ret;
+}
+
+static int __devexit max8649_regulator_remove(struct i2c_client *client)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(client);
+
+	if (info) {
+		if (info->regulator)
+			regulator_unregister(info->regulator);
+		kfree(info);
+	}
+	i2c_set_clientdata(client, NULL);
+
+	return 0;
+}
+
+static const struct i2c_device_id max8649_id[] = {
+	{ "max8649", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max8649_id);
+
+static struct i2c_driver max8649_driver = {
+	.probe		= max8649_regulator_probe,
+	.remove		= __devexit_p(max8649_regulator_remove),
+	.driver		= {
+		.name	= "max8649",
+	},
+	.id_table	= max8649_id,
+};
+
+static int __init max8649_init(void)
+{
+	return i2c_add_driver(&max8649_driver);
+}
+subsys_initcall(max8649_init);
+
+static void __exit max8649_exit(void)
+{
+	i2c_del_driver(&max8649_driver);
+}
+module_exit(max8649_exit);
+
+/* Module information */
+MODULE_DESCRIPTION("MAXIM 8649 voltage regulator driver");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");
+
diff --git a/include/linux/regulator/max8649.h b/include/linux/regulator/max8649.h
new file mode 100644
index 0000000..417d14e
--- /dev/null
+++ b/include/linux/regulator/max8649.h
@@ -0,0 +1,44 @@
+/*
+ * Interface of Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+
+#ifndef __LINUX_REGULATOR_MAX8649_H
+#define	__LINUX_REGULATOR_MAX8649_H
+
+#include <linux/regulator/machine.h>
+
+enum {
+	MAX8649_EXTCLK_26MHZ = 0,
+	MAX8649_EXTCLK_13MHZ,
+	MAX8649_EXTCLK_19MHZ,	/* 19.2MHz */
+};
+
+enum {
+	MAX8649_RAMP_32MV = 0,
+	MAX8649_RAMP_16MV,
+	MAX8649_RAMP_8MV,
+	MAX8649_RAMP_4MV,
+	MAX8649_RAMP_2MV,
+	MAX8649_RAMP_1MV,
+	MAX8649_RAMP_0_5MV,
+	MAX8649_RAMP_0_25MV,
+};
+
+struct max8649_platform_data {
+	struct regulator_init_data *regulator;
+
+	unsigned	mode:2;		/* bit[1:0] = VID1,VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+#endif	/* __LINUX_REGULATOR_MAX8649_H */
-- 
1.5.6.5

Re: [PATCH 01/01] regulator: support max8649

[Liam Girdwood]

On Tue, 2010-01-26 at 01:26 -0500, Haojian Zhuang wrote:
> From 2b5a73c336d2b5dc48c8cf1f2a804b6968659f78 Mon Sep 17 00:00:00 2001
> From: Haojian Zhuang <haojian.zhuang@marvell.com>
> Date: Mon, 25 Jan 2010 10:24:09 -0500
> Subject: [PATCH] regulator: enable max8649 regulator driver
> 
> Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>

Can you confirm all the changes compared to the last version. 

> +static int max8649_get_voltage(struct regulator_dev *rdev)
> +{
> +       struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
> +       unsigned char data;
> +       int ret;
> +
> +       ret = max8649_reg_read(info->i2c, info->vol_reg);
> +       if (ret < 0)
> +               return ret;
> +       data = (unsigned char)ret & MAX8649_VOL_MASK;
> +       return (max8649_list_voltage(rdev, data));

Any reason why we have extra () here ?

Thanks

Liam

Re: [PATCH 01/01] regulator: support max8649

[Mark Brown]

On Tue, Jan 26, 2010 at 01:26:08AM -0500, Haojian Zhuang wrote:

This all looks good except...

> +static int max8649_enable_time(struct regulator_dev *rdev)
> +{

...

> +	return (voltage / step);

I'd expect the time taken to enable to be the voltage multipled by the
step size rather than divided by the step size?

> +static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
> +{
> +	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
> +
> +	switch (mode) {
> +	case REGULATOR_MODE_FAST:
> +		max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
> +				 MAX8649_FORCE_PWM);
> +		break;
> +	case REGULATOR_MODE_NORMAL:
> +		max8649_set_bits(info->i2c, info->vol_reg,
> +				 MAX8649_FORCE_PWM, 0);
> +		break;

This should really have a default case which rejects other modes.

Re: [PATCH 01/01] regulator: support max8649

[Haojian Zhuang]

On Tue, Jan 26, 2010 at 6:01 AM, Liam Girdwood <lrg@slimlogic.co.uk> wrote:
> On Tue, 2010-01-26 at 01:26 -0500, Haojian Zhuang wrote:
>> From 2b5a73c336d2b5dc48c8cf1f2a804b6968659f78 Mon Sep 17 00:00:00 2001
>> From: Haojian Zhuang <haojian.zhuang@marvell.com>
>> Date: Mon, 25 Jan 2010 10:24:09 -0500
>> Subject: [PATCH] regulator: enable max8649 regulator driver
>>
>> Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
>
> Can you confirm all the changes compared to the last version.
>
Yes, exactly.

>> +static int max8649_get_voltage(struct regulator_dev *rdev)
>> +{
>> +       struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
>> +       unsigned char data;
>> +       int ret;
>> +
>> +       ret = max8649_reg_read(info->i2c, info->vol_reg);
>> +       if (ret < 0)
>> +               return ret;
>> +       data = (unsigned char)ret & MAX8649_VOL_MASK;
>> +       return (max8649_list_voltage(rdev, data));
>
> Any reason why we have extra () here ?
>
Fixed.

Re: [PATCH 01/01] regulator: support max8649

[Haojian Zhuang]

[-- Attachment #1: Type: text/plain, Size: 635 bytes --]

On Tue, Jan 26, 2010 at 6:04 AM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> On Tue, Jan 26, 2010 at 01:26:08AM -0500, Haojian Zhuang wrote:
>
> This all looks good except...
>
>> +static int max8649_enable_time(struct regulator_dev *rdev)
>> +{
>
> ...
>
>> +     return (voltage / step);
>
> I'd expect the time taken to enable to be the voltage multipled by the
> step size rather than divided by the step size?
>

I don't agree at this point. The unit of step is uV/uSec. The function
should return uSec. So voltage divided by the step is more reasonable.

Others are updated.

Thanks
Haojian

[-- Attachment #2: 0001-regulator-enable-max8649-regulator-driver.patch --]
[-- Type: text/x-patch, Size: 13590 bytes --]

From 639097ebd0b2c66f89369addd86038ca48f35591 Mon Sep 17 00:00:00 2001
From: Haojian Zhuang <haojian.zhuang@marvell.com>
Date: Mon, 25 Jan 2010 10:24:09 -0500
Subject: [PATCH] regulator: enable max8649 regulator driver

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
---
 drivers/regulator/Kconfig         |    7 +
 drivers/regulator/Makefile        |    1 +
 drivers/regulator/max8649.c       |  408 +++++++++++++++++++++++++++++++++++++
 include/linux/regulator/max8649.h |   44 ++++
 4 files changed, 460 insertions(+), 0 deletions(-)
 create mode 100644 drivers/regulator/max8649.c
 create mode 100644 include/linux/regulator/max8649.h

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 262f62e..a6e7a0c 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -69,6 +69,13 @@ config REGULATOR_MAX1586
 	  regulator via I2C bus. The provided regulator is suitable
 	  for PXA27x chips to control VCC_CORE and VCC_USIM voltages.
 
+config REGULATOR_MAX8649
+	tristate "Maxim 8649 voltage regulator"
+	depends on I2C
+	help
+	  This driver controls a Maxim 8649 voltage output regulator via
+	  I2C bus.
+
 config REGULATOR_MAX8660
 	tristate "Maxim 8660/8661 voltage regulator"
 	depends on I2C
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b3c806c..075835b 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o
 obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o
 obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o
+obj-$(CONFIG_REGULATOR_MAX8649)	+= max8649.o
 obj-$(CONFIG_REGULATOR_MAX8660) += max8660.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o
diff --git a/drivers/regulator/max8649.c b/drivers/regulator/max8649.c
new file mode 100644
index 0000000..9347271
--- /dev/null
+++ b/drivers/regulator/max8649.c
@@ -0,0 +1,408 @@
+/*
+ * Regulators driver for Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/max8649.h>
+
+#define MAX8649_DCDC_VMIN	750000		/* uV */
+#define MAX8649_DCDC_VMAX	1380000		/* uV */
+#define MAX8649_DCDC_STEP	10000		/* uV */
+#define MAX8649_VOL_MASK	0x3f
+
+/* Registers */
+#define MAX8649_MODE0		0x00
+#define MAX8649_MODE1		0x01
+#define MAX8649_MODE2		0x02
+#define MAX8649_MODE3		0x03
+#define MAX8649_CONTROL		0x04
+#define MAX8649_SYNC		0x05
+#define MAX8649_RAMP		0x06
+#define MAX8649_CHIP_ID1	0x08
+#define MAX8649_CHIP_ID2	0x09
+
+/* Bits */
+#define MAX8649_EN_PD		(1 << 7)
+#define MAX8649_VID0_PD		(1 << 6)
+#define MAX8649_VID1_PD		(1 << 5)
+#define MAX8649_VID_MASK	(3 << 5)
+
+#define MAX8649_FORCE_PWM	(1 << 7)
+#define MAX8649_SYNC_EXTCLK	(1 << 6)
+
+#define MAX8649_EXT_MASK	(3 << 6)
+
+#define MAX8649_RAMP_MASK	(7 << 5)
+#define MAX8649_RAMP_DOWN	(1 << 1)
+
+struct max8649_regulator_info {
+	struct regulator_dev	*regulator;
+	struct i2c_client	*i2c;
+	struct device		*dev;
+	struct mutex		io_lock;
+
+	int		vol_reg;
+	unsigned	mode:2;	/* bit[1:0] = VID1, VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+/* I2C operations */
+
+static inline int max8649_read_device(struct i2c_client *i2c,
+				      int reg, int bytes, void *dest)
+{
+	unsigned char data;
+	int ret;
+
+	data = (unsigned char)reg;
+	ret = i2c_master_send(i2c, &data, 1);
+	if (ret < 0)
+		return ret;
+	ret = i2c_master_recv(i2c, dest, bytes);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static inline int max8649_write_device(struct i2c_client *i2c,
+				       int reg, int bytes, void *src)
+{
+	unsigned char buf[bytes + 1];
+	int ret;
+
+	buf[0] = (unsigned char)reg;
+	memcpy(&buf[1], src, bytes);
+
+	ret = i2c_master_send(i2c, buf, bytes + 1);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static int max8649_reg_read(struct i2c_client *i2c, int reg)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char data;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &data);
+	mutex_unlock(&info->io_lock);
+
+	if (ret < 0)
+		return ret;
+	return (int)data;
+}
+
+static int max8649_set_bits(struct i2c_client *i2c, int reg,
+			    unsigned char mask, unsigned char data)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char value;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &value);
+	if (ret < 0)
+		goto out;
+	value &= ~mask;
+	value |= data;
+	ret = max8649_write_device(i2c, reg, 1, &value);
+out:
+	mutex_unlock(&info->io_lock);
+	return ret;
+}
+
+static inline int check_range(int min_uV, int max_uV)
+{
+	if ((min_uV < MAX8649_DCDC_VMIN) || (max_uV > MAX8649_DCDC_VMAX)
+		|| (min_uV > max_uV))
+		return -EINVAL;
+	return 0;
+}
+
+static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
+{
+	return (MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP);
+}
+
+static int max8649_get_voltage(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data;
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret < 0)
+		return ret;
+	data = (unsigned char)ret & MAX8649_VOL_MASK;
+	return max8649_list_voltage(rdev, data);
+}
+
+static int max8649_set_voltage(struct regulator_dev *rdev,
+			       int min_uV, int max_uV)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data, mask;
+
+	if (check_range(min_uV, max_uV)) {
+		dev_err(info->dev, "invalid voltage range (%d, %d) uV\n",
+			min_uV, max_uV);
+		return -EINVAL;
+	}
+	data = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
+		/ MAX8649_DCDC_STEP;
+	mask = MAX8649_VOL_MASK;
+
+	return max8649_set_bits(info->i2c, info->vol_reg, mask, data);
+}
+
+/* EN_PD means pulldown on EN input */
+static int max8649_enable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD, 0);
+}
+
+/*
+ * Applied internal pulldown resistor on EN input pin.
+ * If pulldown EN pin outside, it would be better.
+ */
+static int max8649_disable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD,
+				MAX8649_EN_PD);
+}
+
+static int max8649_is_enabled(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CONTROL);
+	if (ret < 0)
+		return ret;
+	return !((unsigned char)ret & MAX8649_EN_PD);
+}
+
+static int max8649_enable_time(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int voltage, step, ret;
+
+	/* get voltage */
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret < 0)
+		return ret;
+	ret &= MAX8649_VOL_MASK;
+	voltage = max8649_list_voltage(rdev, (unsigned char)ret);	/* uV */
+
+	/* get step */
+	ret = max8649_reg_read(info->i2c, MAX8649_RAMP);
+	if (ret < 0)
+		return ret;
+	ret = (ret & MAX8649_RAMP_MASK) >> 5;
+	step = (32 * 1000) >> ret;	/* uV/uS */
+
+	return (voltage / step);
+}
+
+static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
+				 MAX8649_FORCE_PWM);
+		break;
+	case REGULATOR_MODE_NORMAL:
+		max8649_set_bits(info->i2c, info->vol_reg,
+				 MAX8649_FORCE_PWM, 0);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static unsigned int max8649_get_mode(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret & MAX8649_FORCE_PWM)
+		return REGULATOR_MODE_FAST;
+	return REGULATOR_MODE_NORMAL;
+}
+
+static struct regulator_ops max8649_dcdc_ops = {
+	.set_voltage	= max8649_set_voltage,
+	.get_voltage	= max8649_get_voltage,
+	.list_voltage	= max8649_list_voltage,
+	.enable		= max8649_enable,
+	.disable	= max8649_disable,
+	.is_enabled	= max8649_is_enabled,
+	.enable_time	= max8649_enable_time,
+	.set_mode	= max8649_set_mode,
+	.get_mode	= max8649_get_mode,
+
+};
+
+static struct regulator_desc dcdc_desc = {
+	.name		= "max8649",
+	.ops		= &max8649_dcdc_ops,
+	.type		= REGULATOR_VOLTAGE,
+	.n_voltages	= 1 << 6,
+	.owner		= THIS_MODULE,
+};
+
+static int __devinit max8649_regulator_probe(struct i2c_client *client,
+					     const struct i2c_device_id *id)
+{
+	struct max8649_platform_data *pdata = client->dev.platform_data;
+	struct max8649_regulator_info *info = NULL;
+	unsigned char data;
+	int ret;
+
+	info = kzalloc(sizeof(struct max8649_regulator_info), GFP_KERNEL);
+	if (!info) {
+		dev_err(&client->dev, "No enough memory\n");
+		return -ENOMEM;
+	}
+
+	info->i2c = client;
+	info->dev = &client->dev;
+	mutex_init(&info->io_lock);
+	i2c_set_clientdata(client, info);
+
+	info->mode = pdata->mode;
+	switch (info->mode) {
+	case 0:
+		info->vol_reg = MAX8649_MODE0;
+		break;
+	case 1:
+		info->vol_reg = MAX8649_MODE1;
+		break;
+	case 2:
+		info->vol_reg = MAX8649_MODE2;
+		break;
+	case 3:
+		info->vol_reg = MAX8649_MODE3;
+		break;
+	default:
+		break;
+	}
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CHIP_ID1);
+	if (ret < 0) {
+		dev_err(info->dev, "Failed to detect ID of MAX8649:%d\n",
+			ret);
+		goto out;
+	}
+	dev_info(info->dev, "Detected MAX8649 (ID:%x)\n", ret);
+
+	/* enable VID0 & VID1 */
+	max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
+
+	/* enable/disable external clock synchronization */
+	info->extclk = pdata->extclk;
+	data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
+	max8649_set_bits(info->i2c, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
+	if (info->extclk) {
+		/* set external clock frequency */
+		info->extclk_freq = pdata->extclk_freq;
+		max8649_set_bits(info->i2c, MAX8649_SYNC, MAX8649_EXT_MASK,
+				 info->extclk_freq);
+	}
+
+	if (pdata->ramp_timing) {
+		info->ramp_timing = pdata->ramp_timing;
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
+				 info->ramp_timing << 5);
+	}
+
+	info->ramp_down = pdata->ramp_down;
+	if (info->ramp_down) {
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_DOWN,
+				 MAX8649_RAMP_DOWN);
+	}
+
+	info->regulator = regulator_register(&dcdc_desc, &client->dev,
+					     pdata->regulator, info);
+	if (IS_ERR(info->regulator)) {
+		dev_err(info->dev, "failed to register regulator %s\n",
+			dcdc_desc.name);
+		ret = PTR_ERR(info->regulator);
+		goto out;
+	}
+
+	dev_info(info->dev, "Max8649 regulator device is detected.\n");
+	return 0;
+out:
+	kfree(info);
+	return ret;
+}
+
+static int __devexit max8649_regulator_remove(struct i2c_client *client)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(client);
+
+	if (info) {
+		if (info->regulator)
+			regulator_unregister(info->regulator);
+		kfree(info);
+	}
+	i2c_set_clientdata(client, NULL);
+
+	return 0;
+}
+
+static const struct i2c_device_id max8649_id[] = {
+	{ "max8649", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max8649_id);
+
+static struct i2c_driver max8649_driver = {
+	.probe		= max8649_regulator_probe,
+	.remove		= __devexit_p(max8649_regulator_remove),
+	.driver		= {
+		.name	= "max8649",
+	},
+	.id_table	= max8649_id,
+};
+
+static int __init max8649_init(void)
+{
+	return i2c_add_driver(&max8649_driver);
+}
+subsys_initcall(max8649_init);
+
+static void __exit max8649_exit(void)
+{
+	i2c_del_driver(&max8649_driver);
+}
+module_exit(max8649_exit);
+
+/* Module information */
+MODULE_DESCRIPTION("MAXIM 8649 voltage regulator driver");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");
+
diff --git a/include/linux/regulator/max8649.h b/include/linux/regulator/max8649.h
new file mode 100644
index 0000000..417d14e
--- /dev/null
+++ b/include/linux/regulator/max8649.h
@@ -0,0 +1,44 @@
+/*
+ * Interface of Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+
+#ifndef __LINUX_REGULATOR_MAX8649_H
+#define	__LINUX_REGULATOR_MAX8649_H
+
+#include <linux/regulator/machine.h>
+
+enum {
+	MAX8649_EXTCLK_26MHZ = 0,
+	MAX8649_EXTCLK_13MHZ,
+	MAX8649_EXTCLK_19MHZ,	/* 19.2MHz */
+};
+
+enum {
+	MAX8649_RAMP_32MV = 0,
+	MAX8649_RAMP_16MV,
+	MAX8649_RAMP_8MV,
+	MAX8649_RAMP_4MV,
+	MAX8649_RAMP_2MV,
+	MAX8649_RAMP_1MV,
+	MAX8649_RAMP_0_5MV,
+	MAX8649_RAMP_0_25MV,
+};
+
+struct max8649_platform_data {
+	struct regulator_init_data *regulator;
+
+	unsigned	mode:2;		/* bit[1:0] = VID1,VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+#endif	/* __LINUX_REGULATOR_MAX8649_H */
-- 
1.5.6.5

Re: [PATCH 01/01] regulator: support max8649

[Mark Brown]

On Tue, Jan 26, 2010 at 06:54:48AM -0500, Haojian Zhuang wrote:
> On Tue, Jan 26, 2010 at 6:04 AM, Mark Brown

> > I'd expect the time taken to enable to be the voltage multipled by the
> > step size rather than divided by the step size?

> I don't agree at this point. The unit of step is uV/uSec. The function
> should return uSec. So voltage divided by the step is more reasonable.

Ah, then the variable step is confusingly named since it's actually a
rate of change rather than a step size - I'd suggest rate or something
like that instead.

Re: [PATCH 01/01] regulator: support max8649

[Haojian Zhuang]

[-- Attachment #1: Type: text/plain, Size: 689 bytes --]

On Tue, Jan 26, 2010 at 7:00 AM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> On Tue, Jan 26, 2010 at 06:54:48AM -0500, Haojian Zhuang wrote:
>> On Tue, Jan 26, 2010 at 6:04 AM, Mark Brown
>
>> > I'd expect the time taken to enable to be the voltage multipled by the
>> > step size rather than divided by the step size?
>
>> I don't agree at this point. The unit of step is uV/uSec. The function
>> should return uSec. So voltage divided by the step is more reasonable.
>
> Ah, then the variable step is confusingly named since it's actually a
> rate of change rather than a step size - I'd suggest rate or something
> like that instead.
>

update this patch.

Thanks
Haojian

[-- Attachment #2: 0001-regulator-enable-max8649-regulator-driver.patch --]
[-- Type: text/x-patch, Size: 13590 bytes --]

From 943cd245d50a85b369ad07af4c9c977e14836c63 Mon Sep 17 00:00:00 2001
From: Haojian Zhuang <haojian.zhuang@marvell.com>
Date: Mon, 25 Jan 2010 10:24:09 -0500
Subject: [PATCH] regulator: enable max8649 regulator driver

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
---
 drivers/regulator/Kconfig         |    7 +
 drivers/regulator/Makefile        |    1 +
 drivers/regulator/max8649.c       |  408 +++++++++++++++++++++++++++++++++++++
 include/linux/regulator/max8649.h |   44 ++++
 4 files changed, 460 insertions(+), 0 deletions(-)
 create mode 100644 drivers/regulator/max8649.c
 create mode 100644 include/linux/regulator/max8649.h

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 262f62e..a6e7a0c 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -69,6 +69,13 @@ config REGULATOR_MAX1586
 	  regulator via I2C bus. The provided regulator is suitable
 	  for PXA27x chips to control VCC_CORE and VCC_USIM voltages.
 
+config REGULATOR_MAX8649
+	tristate "Maxim 8649 voltage regulator"
+	depends on I2C
+	help
+	  This driver controls a Maxim 8649 voltage output regulator via
+	  I2C bus.
+
 config REGULATOR_MAX8660
 	tristate "Maxim 8660/8661 voltage regulator"
 	depends on I2C
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b3c806c..075835b 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o
 obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o
 obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o
+obj-$(CONFIG_REGULATOR_MAX8649)	+= max8649.o
 obj-$(CONFIG_REGULATOR_MAX8660) += max8660.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-isink.o
diff --git a/drivers/regulator/max8649.c b/drivers/regulator/max8649.c
new file mode 100644
index 0000000..3ebdf69
--- /dev/null
+++ b/drivers/regulator/max8649.c
@@ -0,0 +1,408 @@
+/*
+ * Regulators driver for Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/max8649.h>
+
+#define MAX8649_DCDC_VMIN	750000		/* uV */
+#define MAX8649_DCDC_VMAX	1380000		/* uV */
+#define MAX8649_DCDC_STEP	10000		/* uV */
+#define MAX8649_VOL_MASK	0x3f
+
+/* Registers */
+#define MAX8649_MODE0		0x00
+#define MAX8649_MODE1		0x01
+#define MAX8649_MODE2		0x02
+#define MAX8649_MODE3		0x03
+#define MAX8649_CONTROL		0x04
+#define MAX8649_SYNC		0x05
+#define MAX8649_RAMP		0x06
+#define MAX8649_CHIP_ID1	0x08
+#define MAX8649_CHIP_ID2	0x09
+
+/* Bits */
+#define MAX8649_EN_PD		(1 << 7)
+#define MAX8649_VID0_PD		(1 << 6)
+#define MAX8649_VID1_PD		(1 << 5)
+#define MAX8649_VID_MASK	(3 << 5)
+
+#define MAX8649_FORCE_PWM	(1 << 7)
+#define MAX8649_SYNC_EXTCLK	(1 << 6)
+
+#define MAX8649_EXT_MASK	(3 << 6)
+
+#define MAX8649_RAMP_MASK	(7 << 5)
+#define MAX8649_RAMP_DOWN	(1 << 1)
+
+struct max8649_regulator_info {
+	struct regulator_dev	*regulator;
+	struct i2c_client	*i2c;
+	struct device		*dev;
+	struct mutex		io_lock;
+
+	int		vol_reg;
+	unsigned	mode:2;	/* bit[1:0] = VID1, VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+/* I2C operations */
+
+static inline int max8649_read_device(struct i2c_client *i2c,
+				      int reg, int bytes, void *dest)
+{
+	unsigned char data;
+	int ret;
+
+	data = (unsigned char)reg;
+	ret = i2c_master_send(i2c, &data, 1);
+	if (ret < 0)
+		return ret;
+	ret = i2c_master_recv(i2c, dest, bytes);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static inline int max8649_write_device(struct i2c_client *i2c,
+				       int reg, int bytes, void *src)
+{
+	unsigned char buf[bytes + 1];
+	int ret;
+
+	buf[0] = (unsigned char)reg;
+	memcpy(&buf[1], src, bytes);
+
+	ret = i2c_master_send(i2c, buf, bytes + 1);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static int max8649_reg_read(struct i2c_client *i2c, int reg)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char data;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &data);
+	mutex_unlock(&info->io_lock);
+
+	if (ret < 0)
+		return ret;
+	return (int)data;
+}
+
+static int max8649_set_bits(struct i2c_client *i2c, int reg,
+			    unsigned char mask, unsigned char data)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+	unsigned char value;
+	int ret;
+
+	mutex_lock(&info->io_lock);
+	ret = max8649_read_device(i2c, reg, 1, &value);
+	if (ret < 0)
+		goto out;
+	value &= ~mask;
+	value |= data;
+	ret = max8649_write_device(i2c, reg, 1, &value);
+out:
+	mutex_unlock(&info->io_lock);
+	return ret;
+}
+
+static inline int check_range(int min_uV, int max_uV)
+{
+	if ((min_uV < MAX8649_DCDC_VMIN) || (max_uV > MAX8649_DCDC_VMAX)
+		|| (min_uV > max_uV))
+		return -EINVAL;
+	return 0;
+}
+
+static int max8649_list_voltage(struct regulator_dev *rdev, unsigned index)
+{
+	return (MAX8649_DCDC_VMIN + index * MAX8649_DCDC_STEP);
+}
+
+static int max8649_get_voltage(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data;
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret < 0)
+		return ret;
+	data = (unsigned char)ret & MAX8649_VOL_MASK;
+	return max8649_list_voltage(rdev, data);
+}
+
+static int max8649_set_voltage(struct regulator_dev *rdev,
+			       int min_uV, int max_uV)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	unsigned char data, mask;
+
+	if (check_range(min_uV, max_uV)) {
+		dev_err(info->dev, "invalid voltage range (%d, %d) uV\n",
+			min_uV, max_uV);
+		return -EINVAL;
+	}
+	data = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
+		/ MAX8649_DCDC_STEP;
+	mask = MAX8649_VOL_MASK;
+
+	return max8649_set_bits(info->i2c, info->vol_reg, mask, data);
+}
+
+/* EN_PD means pulldown on EN input */
+static int max8649_enable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD, 0);
+}
+
+/*
+ * Applied internal pulldown resistor on EN input pin.
+ * If pulldown EN pin outside, it would be better.
+ */
+static int max8649_disable(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	return max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_EN_PD,
+				MAX8649_EN_PD);
+}
+
+static int max8649_is_enabled(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CONTROL);
+	if (ret < 0)
+		return ret;
+	return !((unsigned char)ret & MAX8649_EN_PD);
+}
+
+static int max8649_enable_time(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int voltage, rate, ret;
+
+	/* get voltage */
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret < 0)
+		return ret;
+	ret &= MAX8649_VOL_MASK;
+	voltage = max8649_list_voltage(rdev, (unsigned char)ret); /* uV */
+
+	/* get rate */
+	ret = max8649_reg_read(info->i2c, MAX8649_RAMP);
+	if (ret < 0)
+		return ret;
+	ret = (ret & MAX8649_RAMP_MASK) >> 5;
+	rate = (32 * 1000) >> ret;	/* uV/uS */
+
+	return (voltage / rate);
+}
+
+static int max8649_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
+				 MAX8649_FORCE_PWM);
+		break;
+	case REGULATOR_MODE_NORMAL:
+		max8649_set_bits(info->i2c, info->vol_reg,
+				 MAX8649_FORCE_PWM, 0);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static unsigned int max8649_get_mode(struct regulator_dev *rdev)
+{
+	struct max8649_regulator_info *info = rdev_get_drvdata(rdev);
+	int ret;
+
+	ret = max8649_reg_read(info->i2c, info->vol_reg);
+	if (ret & MAX8649_FORCE_PWM)
+		return REGULATOR_MODE_FAST;
+	return REGULATOR_MODE_NORMAL;
+}
+
+static struct regulator_ops max8649_dcdc_ops = {
+	.set_voltage	= max8649_set_voltage,
+	.get_voltage	= max8649_get_voltage,
+	.list_voltage	= max8649_list_voltage,
+	.enable		= max8649_enable,
+	.disable	= max8649_disable,
+	.is_enabled	= max8649_is_enabled,
+	.enable_time	= max8649_enable_time,
+	.set_mode	= max8649_set_mode,
+	.get_mode	= max8649_get_mode,
+
+};
+
+static struct regulator_desc dcdc_desc = {
+	.name		= "max8649",
+	.ops		= &max8649_dcdc_ops,
+	.type		= REGULATOR_VOLTAGE,
+	.n_voltages	= 1 << 6,
+	.owner		= THIS_MODULE,
+};
+
+static int __devinit max8649_regulator_probe(struct i2c_client *client,
+					     const struct i2c_device_id *id)
+{
+	struct max8649_platform_data *pdata = client->dev.platform_data;
+	struct max8649_regulator_info *info = NULL;
+	unsigned char data;
+	int ret;
+
+	info = kzalloc(sizeof(struct max8649_regulator_info), GFP_KERNEL);
+	if (!info) {
+		dev_err(&client->dev, "No enough memory\n");
+		return -ENOMEM;
+	}
+
+	info->i2c = client;
+	info->dev = &client->dev;
+	mutex_init(&info->io_lock);
+	i2c_set_clientdata(client, info);
+
+	info->mode = pdata->mode;
+	switch (info->mode) {
+	case 0:
+		info->vol_reg = MAX8649_MODE0;
+		break;
+	case 1:
+		info->vol_reg = MAX8649_MODE1;
+		break;
+	case 2:
+		info->vol_reg = MAX8649_MODE2;
+		break;
+	case 3:
+		info->vol_reg = MAX8649_MODE3;
+		break;
+	default:
+		break;
+	}
+
+	ret = max8649_reg_read(info->i2c, MAX8649_CHIP_ID1);
+	if (ret < 0) {
+		dev_err(info->dev, "Failed to detect ID of MAX8649:%d\n",
+			ret);
+		goto out;
+	}
+	dev_info(info->dev, "Detected MAX8649 (ID:%x)\n", ret);
+
+	/* enable VID0 & VID1 */
+	max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
+
+	/* enable/disable external clock synchronization */
+	info->extclk = pdata->extclk;
+	data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
+	max8649_set_bits(info->i2c, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
+	if (info->extclk) {
+		/* set external clock frequency */
+		info->extclk_freq = pdata->extclk_freq;
+		max8649_set_bits(info->i2c, MAX8649_SYNC, MAX8649_EXT_MASK,
+				 info->extclk_freq);
+	}
+
+	if (pdata->ramp_timing) {
+		info->ramp_timing = pdata->ramp_timing;
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
+				 info->ramp_timing << 5);
+	}
+
+	info->ramp_down = pdata->ramp_down;
+	if (info->ramp_down) {
+		max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_DOWN,
+				 MAX8649_RAMP_DOWN);
+	}
+
+	info->regulator = regulator_register(&dcdc_desc, &client->dev,
+					     pdata->regulator, info);
+	if (IS_ERR(info->regulator)) {
+		dev_err(info->dev, "failed to register regulator %s\n",
+			dcdc_desc.name);
+		ret = PTR_ERR(info->regulator);
+		goto out;
+	}
+
+	dev_info(info->dev, "Max8649 regulator device is detected.\n");
+	return 0;
+out:
+	kfree(info);
+	return ret;
+}
+
+static int __devexit max8649_regulator_remove(struct i2c_client *client)
+{
+	struct max8649_regulator_info *info = i2c_get_clientdata(client);
+
+	if (info) {
+		if (info->regulator)
+			regulator_unregister(info->regulator);
+		kfree(info);
+	}
+	i2c_set_clientdata(client, NULL);
+
+	return 0;
+}
+
+static const struct i2c_device_id max8649_id[] = {
+	{ "max8649", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max8649_id);
+
+static struct i2c_driver max8649_driver = {
+	.probe		= max8649_regulator_probe,
+	.remove		= __devexit_p(max8649_regulator_remove),
+	.driver		= {
+		.name	= "max8649",
+	},
+	.id_table	= max8649_id,
+};
+
+static int __init max8649_init(void)
+{
+	return i2c_add_driver(&max8649_driver);
+}
+subsys_initcall(max8649_init);
+
+static void __exit max8649_exit(void)
+{
+	i2c_del_driver(&max8649_driver);
+}
+module_exit(max8649_exit);
+
+/* Module information */
+MODULE_DESCRIPTION("MAXIM 8649 voltage regulator driver");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");
+
diff --git a/include/linux/regulator/max8649.h b/include/linux/regulator/max8649.h
new file mode 100644
index 0000000..417d14e
--- /dev/null
+++ b/include/linux/regulator/max8649.h
@@ -0,0 +1,44 @@
+/*
+ * Interface of Maxim max8649
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ *      Haojian Zhuang <haojian.zhuang@marvell.com>
+ *
+ * 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.
+ */
+
+#ifndef __LINUX_REGULATOR_MAX8649_H
+#define	__LINUX_REGULATOR_MAX8649_H
+
+#include <linux/regulator/machine.h>
+
+enum {
+	MAX8649_EXTCLK_26MHZ = 0,
+	MAX8649_EXTCLK_13MHZ,
+	MAX8649_EXTCLK_19MHZ,	/* 19.2MHz */
+};
+
+enum {
+	MAX8649_RAMP_32MV = 0,
+	MAX8649_RAMP_16MV,
+	MAX8649_RAMP_8MV,
+	MAX8649_RAMP_4MV,
+	MAX8649_RAMP_2MV,
+	MAX8649_RAMP_1MV,
+	MAX8649_RAMP_0_5MV,
+	MAX8649_RAMP_0_25MV,
+};
+
+struct max8649_platform_data {
+	struct regulator_init_data *regulator;
+
+	unsigned	mode:2;		/* bit[1:0] = VID1,VID0 */
+	unsigned	extclk_freq:2;
+	unsigned	extclk:1;
+	unsigned	ramp_timing:3;
+	unsigned	ramp_down:1;
+};
+
+#endif	/* __LINUX_REGULATOR_MAX8649_H */
-- 
1.5.6.5

Re: [PATCH 01/01] regulator: support max8649

[Mark Brown]

On Tue, Jan 26, 2010 at 07:14:14AM -0500, Haojian Zhuang wrote:

> update this patch.

Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

As Liam said previously it'd be handy if you could explicitly list the
changes when you provide new patches - this makes it much easier to
focus in on the bits that need incremental review.

Re: [PATCH 01/01] regulator: support max8649

[Liam Girdwood]

On Tue, 2010-01-26 at 07:14 -0500, Haojian Zhuang wrote:
> On Tue, Jan 26, 2010 at 7:00 AM, Mark Brown
> <broonie@opensource.wolfsonmicro.com> wrote:
> > On Tue, Jan 26, 2010 at 06:54:48AM -0500, Haojian Zhuang wrote:
> >> On Tue, Jan 26, 2010 at 6:04 AM, Mark Brown
> >
> >> > I'd expect the time taken to enable to be the voltage multipled by the
> >> > step size rather than divided by the step size?
> >
> >> I don't agree at this point. The unit of step is uV/uSec. The function
> >> should return uSec. So voltage divided by the step is more reasonable.
> >
> > Ah, then the variable step is confusingly named since it's actually a
> > rate of change rather than a step size - I'd suggest rate or something
> > like that instead.
> >
> 
> update this patch.
> 

Applied.

Thanks

Liam

Re: [PATCH 01/01] regulator: support max8649

[Haojian Zhuang]

On Tue, Jan 26, 2010 at 11:10 AM, Liam Girdwood <lrg@slimlogic.co.uk> wrote:
> On Tue, 2010-01-26 at 07:14 -0500, Haojian Zhuang wrote:
>> On Tue, Jan 26, 2010 at 7:00 AM, Mark Brown
>> <broonie@opensource.wolfsonmicro.com> wrote:
>> >
>>
>> update this patch.
>>
>
> Applied.
>
> Thanks
>
> Liam
>
>

Hi Liam & Mark,

I just want to confirm whether max8649 is merged into regulator
codebase. It seems that I can't find max8649 in regulator git tree.

Thanks
Haojian

Re: [PATCH 01/01] regulator: support max8649

[Liam Girdwood]

On Mon, 2010-03-08 at 01:28 -0500, Haojian Zhuang wrote:
> On Tue, Jan 26, 2010 at 11:10 AM, Liam Girdwood <lrg@slimlogic.co.uk> wrote:
> > On Tue, 2010-01-26 at 07:14 -0500, Haojian Zhuang wrote:
> >> On Tue, Jan 26, 2010 at 7:00 AM, Mark Brown
> >> <broonie@opensource.wolfsonmicro.com> wrote:
> >> >
> >>
> >> update this patch.
> >>
> >
> > Applied.
> >
> > Thanks
> >
> > Liam
> >
> >
> 
> Hi Liam & Mark,
> 
> I just want to confirm whether max8649 is merged into regulator
> codebase. It seems that I can't find max8649 in regulator git tree.

max8649 was merged into regulator and has now been pulled by Linus.

Where were you looking ?

Thanks

Liam

-- 
Freelance Developer, SlimLogic Ltd
ASoC and Voltage Regulator Maintainer.
http://www.slimlogic.co.uk