diff mbox

[2/5] regulator: Add driver for Maxim 77802 PMIC regulators

Message ID 1402306670-17041-3-git-send-email-javier.martinez@collabora.co.uk
State Superseded
Headers show

Commit Message

Javier Martinez Canillas June 9, 2014, 9:37 a.m. UTC
The MAX77802 PMIC has 10 high-efficiency Buck and 32 Low-dropout
(LDO) regulators. This patch adds support for all these regulators
found on the MAX77802 PMIC and is based on a driver added by Simon
Glass to the Chrome OS kernel 3.8 tree.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
---
 drivers/regulator/Kconfig    |   9 +
 drivers/regulator/Makefile   |   1 +
 drivers/regulator/max77802.c | 678 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 688 insertions(+)
 create mode 100644 drivers/regulator/max77802.c

Comments

Mark Brown June 9, 2014, 7:38 p.m. UTC | #1
On Mon, Jun 09, 2014 at 11:37:47AM +0200, Javier Martinez Canillas wrote:

> +	case REGULATOR_MODE_STANDBY:			/* switch off */
> +		if (id != MAX77802_LDO1 && id != MAX77802_LDO20 &&
> +			id != MAX77802_LDO21 && id != MAX77802_LDO3) {
> +			val = MAX77802_OPMODE_STANDBY;
> +			break;
> +		}
> +		/* no break */

This sounds very broken...

> +		/* OK if some GPIOs aren't defined */
> +		if (!gpio_is_valid(gpio))
> +			continue;
> +
> +		/* If a GPIO is valid, we'd better be able to claim it */
> +		ret = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
> +					    "max77802 selb");
> +		if (ret) {
> +			dev_err(dev, "can't claim gpio[%d]: %d\n", i, ret);
> +			return ret;
> +		}

Can this use the GPIO descriptor API?

> +static void max77802_copy_reg(struct device *dev, struct regmap *regmap,
> +			      int from_reg, int to_reg)
> +{
> +	int val;
> +	int ret;
> +
> +	if (from_reg == to_reg)
> +		return;
> +
> +	ret = regmap_read(regmap, from_reg, &val);
> +	if (!ret)
> +		ret = regmap_write(regmap, to_reg, val);
> +
> +	if (ret)
> +		dev_warn(dev, "Copy err %d => %d (%d)\n",
> +			 from_reg, to_reg, ret);
> +}

This doesn't look at all device specific, better implement it in generic
code.

> +	if (pdata->num_regulators != MAX77802_MAX_REGULATORS) {
> +		dev_err(&pdev->dev,
> +			"Invalid initial data for regulator's initialiation: " \
> +			"expected %d, pdata/dt provided %d\n",
> +			MAX77802_MAX_REGULATORS,
> +			pdata->num_regulators);
> +		return -EINVAL;
> +	}

Don't split log messages over multiple lines so people can find the log
message in the kernel source with grep, though in any case checking for
this is a bug - the driver should always be at least able to read the
current state from the hardware.

> +static int __init max77802_pmic_init(void)
> +{
> +	return platform_driver_register(&max77802_pmic_driver);
> +}
> +subsys_initcall(max77802_pmic_init);

module_platform_driver().
Javier Martinez Canillas June 9, 2014, 11:29 p.m. UTC | #2
Hello Mark,

Thanks a lot for your feedback.

On 06/09/2014 09:38 PM, Mark Brown wrote:
> On Mon, Jun 09, 2014 at 11:37:47AM +0200, Javier Martinez Canillas wrote:
> 
>> +	case REGULATOR_MODE_STANDBY:			/* switch off */
>> +		if (id != MAX77802_LDO1 && id != MAX77802_LDO20 &&
>> +			id != MAX77802_LDO21 && id != MAX77802_LDO3) {
>> +			val = MAX77802_OPMODE_STANDBY;
>> +			break;
>> +		}
>> +		/* no break */
> 
> This sounds very broken...
>

The problem is that not all regulators supports the same operational modes. For
instance regulators LDO 1, 20, 21 and 3 does not support REGULATOR_MODE_STANDBY
so if the condition is not met a break is not needed since the default case is
to warn that the mode is not supported.

But I'll rework that logic on v2 to make it cleaner and have a break on each
case and don't rely on case cascading.

>> +		/* OK if some GPIOs aren't defined */
>> +		if (!gpio_is_valid(gpio))
>> +			continue;
>> +
>> +		/* If a GPIO is valid, we'd better be able to claim it */
>> +		ret = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
>> +					    "max77802 selb");
>> +		if (ret) {
>> +			dev_err(dev, "can't claim gpio[%d]: %d\n", i, ret);
>> +			return ret;
>> +		}
> 
> Can this use the GPIO descriptor API?
> 

Ok, I'll use gpiod_request() on v2.

>> +static void max77802_copy_reg(struct device *dev, struct regmap *regmap,
>> +			      int from_reg, int to_reg)
>> +{
>> +	int val;
>> +	int ret;
>> +
>> +	if (from_reg == to_reg)
>> +		return;
>> +
>> +	ret = regmap_read(regmap, from_reg, &val);
>> +	if (!ret)
>> +		ret = regmap_write(regmap, to_reg, val);
>> +
>> +	if (ret)
>> +		dev_warn(dev, "Copy err %d => %d (%d)\n",
>> +			 from_reg, to_reg, ret);
>> +}
> 
> This doesn't look at all device specific, better implement it in generic
> code.
> 

Ok, will do.

>> +	if (pdata->num_regulators != MAX77802_MAX_REGULATORS) {
>> +		dev_err(&pdev->dev,
>> +			"Invalid initial data for regulator's initialiation: " \
>> +			"expected %d, pdata/dt provided %d\n",
>> +			MAX77802_MAX_REGULATORS,
>> +			pdata->num_regulators);
>> +		return -EINVAL;
>> +	}
> 
> Don't split log messages over multiple lines so people can find the log
> message in the kernel source with grep, though in any case checking for
> this is a bug - the driver should always be at least able to read the
> current state from the hardware.
> 

Ok.

>> +static int __init max77802_pmic_init(void)
>> +{
>> +	return platform_driver_register(&max77802_pmic_driver);
>> +}
>> +subsys_initcall(max77802_pmic_init);
> 
> module_platform_driver().
> 

Ok.

Best regards,
Javier
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Mark Brown June 10, 2014, 10:53 a.m. UTC | #3
On Tue, Jun 10, 2014 at 01:29:17AM +0200, Javier Martinez Canillas wrote:
> On 06/09/2014 09:38 PM, Mark Brown wrote:
> > On Mon, Jun 09, 2014 at 11:37:47AM +0200, Javier Martinez Canillas wrote:

> >> +	case REGULATOR_MODE_STANDBY:			/* switch off */
> >> +		if (id != MAX77802_LDO1 && id != MAX77802_LDO20 &&
> >> +			id != MAX77802_LDO21 && id != MAX77802_LDO3) {
> >> +			val = MAX77802_OPMODE_STANDBY;
> >> +			break;
> >> +		}
> >> +		/* no break */

> > This sounds very broken...

> The problem is that not all regulators supports the same operational modes. For
> instance regulators LDO 1, 20, 21 and 3 does not support REGULATOR_MODE_STANDBY
> so if the condition is not met a break is not needed since the default case is
> to warn that the mode is not supported.

No, it's the "switch off" comment...

> But I'll rework that logic on v2 to make it cleaner and have a break on each
> case and don't rely on case cascading.

...though you should also consider splitting things up so you have
separate ops for separate regulators if they behave differently.
diff mbox

Patch

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 789eb46..17873d3 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -377,6 +377,15 @@  config REGULATOR_MAX77693
 	  and one current regulator 'CHARGER'. This is suitable for
 	  Exynos-4x12 chips.
 
+config REGULATOR_MAX77802
+	tristate "Maxim 77802 regulator"
+	depends on MFD_MAX77802
+	help
+	  This driver controls a Maxim 77802 regulator
+	  via I2C bus. The provided regulator is suitable for
+	  Exynos-5 chips to control various voltages. It includes
+	  support for control of voltage and ramp speed.
+
 config REGULATOR_MC13XXX_CORE
 	tristate
 
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index d461110..2aea4b6 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -51,6 +51,7 @@  obj-$(CONFIG_REGULATOR_MAX8997) += max8997.o
 obj-$(CONFIG_REGULATOR_MAX8998) += max8998.o
 obj-$(CONFIG_REGULATOR_MAX77686) += max77686.o
 obj-$(CONFIG_REGULATOR_MAX77693) += max77693.o
+obj-$(CONFIG_REGULATOR_MAX77802) += max77802.o
 obj-$(CONFIG_REGULATOR_MC13783) += mc13783-regulator.o
 obj-$(CONFIG_REGULATOR_MC13892) += mc13892-regulator.o
 obj-$(CONFIG_REGULATOR_MC13XXX_CORE) +=  mc13xxx-regulator-core.o
diff --git a/drivers/regulator/max77802.c b/drivers/regulator/max77802.c
new file mode 100644
index 0000000..93e8f69
--- /dev/null
+++ b/drivers/regulator/max77802.c
@@ -0,0 +1,678 @@ 
+/*
+ * max77802.c - Regulator driver for the Maxim 77802
+ *
+ * Copyright (C) 2013-2014 Google, Inc
+ * Simon Glass <sjg@chromium.org>
+ *
+ * Copyright (C) 2012 Samsung Electronics
+ * Chiwoong Byun <woong.byun@smasung.com>
+ * Jonghwa Lee <jonghwa3.lee@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * This driver is based on max8997.c
+ */
+
+#include <linux/kernel.h>
+#include <linux/bug.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/mfd/max77802.h>
+#include <linux/mfd/max77802-private.h>
+
+/* Default ramp delay in case it is not manually set */
+#define MAX77802_RAMP_DELAY		100000		/* uV/us */
+
+#define MAX77802_OPMODE_SHIFT_LDO	6
+#define MAX77802_OPMODE_BUCK234_SHIFT	4
+#define MAX77802_OPMODE_MASK		0x3
+
+#define MAX77802_VSEL_MASK		0x3F
+#define MAX77802_DVS_VSEL_MASK		0xFF
+
+#define MAX77802_RAMP_RATE_MASK_2BIT	0xC0
+#define MAX77802_RAMP_RATE_SHIFT_2BIT	6
+#define MAX77802_RAMP_RATE_MASK_4BIT	0xF0
+#define MAX77802_RAMP_RATE_SHIFT_4BIT	4
+
+/* LDO16, LDO22 and LDO31 are not available on MAX77802 */
+#define MAX77802_MAX_REGULATORS		(MAX77802_REG_MAX - 3)
+
+/* MAX77802 has two register formats: 2-bit and 4-bit */
+static const unsigned int ramp_table_77802_2bit[] = {
+	12500,
+	25000,
+	50000,
+	100000,
+};
+
+static unsigned int ramp_table_77802_4bit[] = {
+	1000,	2000,	3030,	4000,
+	5000,	5880,	7140,	8330,
+	9090,	10000,	11110,	12500,
+	16670,	25000,	50000,	100000,
+};
+
+struct max77802_regulator_prv {
+	int num_regulators;
+	struct regulator_dev *rdev[MAX77802_MAX_REGULATORS];
+	unsigned int opmode[MAX77802_MAX_REGULATORS];
+};
+
+static int max77802_get_opmode_shift(int id)
+{
+	if (id >= MAX77802_LDO1 && id <= MAX77802_LDO35)
+		return MAX77802_OPMODE_SHIFT_LDO;
+	else if (id == MAX77802_BUCK1 || (id >= MAX77802_BUCK5 &&
+					  id <= MAX77802_BUCK10))
+		return 0;
+	else if (id >= MAX77802_BUCK2 && id <= MAX77802_BUCK4)
+		return MAX77802_OPMODE_BUCK234_SHIFT;
+	else
+		return -EINVAL;
+}
+
+/*
+ * Some BUCKS supports Normal[ON/OFF] mode during suspend
+ *
+ * BUCK 1, 6, 2-4, 5, 7-10 (all)
+ *
+ * The other mode (0x02) will make pwrreq switch between normal
+ * and low power.
+ */
+static int max77802_buck_set_suspend_disable(struct regulator_dev *rdev)
+{
+	unsigned int val = MAX77802_OPMODE_STANDBY;
+	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	int shift = max77802_get_opmode_shift(id);
+
+	max77802->opmode[id] = val;
+	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+				  rdev->desc->enable_mask, val << shift);
+}
+
+/*
+ * Some LDOs supports LPM-ON/OFF/Normal-ON mode during suspend state
+ *
+ * LDOs 3-7, 9-14, 18-26, 28, 29, 32-34, 1, 2, 8, 15, 17, 27, 30, 35 (all)
+ *
+ * LDOs 1, 20, 21, and 3, mode 1 is not supported
+ */
+static int max77802_ldo_set_suspend_mode(struct regulator_dev *rdev,
+					 unsigned int mode)
+{
+	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	unsigned int val;
+	int shift = max77802_get_opmode_shift(id);
+
+	switch (mode) {
+	case REGULATOR_MODE_IDLE:			/* ON in LP Mode */
+		val = MAX77802_OPMODE_LP;
+		break;
+	case REGULATOR_MODE_NORMAL:			/* ON in Normal Mode */
+		val = MAX77802_OPMODE_NORMAL;
+		break;
+	case REGULATOR_MODE_STANDBY:			/* switch off */
+		if (id != MAX77802_LDO1 && id != MAX77802_LDO20 &&
+			id != MAX77802_LDO21 && id != MAX77802_LDO3) {
+			val = MAX77802_OPMODE_STANDBY;
+			break;
+		}
+		/* no break */
+	default:
+		pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
+			rdev->desc->name, mode);
+		return -EINVAL;
+	}
+
+	max77802->opmode[rdev_get_id(rdev)] = val;
+	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+				  rdev->desc->enable_mask, val << shift);
+}
+
+static int max77802_enable(struct regulator_dev *rdev)
+{
+	struct max77802_regulator_prv *max77802 = rdev_get_drvdata(rdev);
+	int id = rdev_get_id(rdev);
+	int shift = max77802_get_opmode_shift(id);
+
+	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+				  rdev->desc->enable_mask,
+				  max77802->opmode[id] << shift);
+}
+
+static int max77802_find_ramp_value(struct regulator_dev *rdev,
+				    const unsigned int limits[], int size,
+				    unsigned int ramp_delay)
+{
+	int i;
+
+	for (i = 0; i < size; i++) {
+		if (ramp_delay <= limits[i])
+			return i;
+	}
+
+	/* Use maximum value for no ramp control */
+	pr_warn("%s: ramp_delay: %d not supported, setting 100000\n",
+		rdev->desc->name, ramp_delay);
+	return size - 1;
+}
+
+/* Used for BUCKs 2-4 */
+static int max77802_set_ramp_delay_2bit(struct regulator_dev *rdev,
+					int ramp_delay)
+{
+	int id = rdev_get_id(rdev);
+	unsigned int ramp_value;
+
+	if (id > MAX77802_BUCK4) {
+		pr_warn("%s: regulator_suspend_mode: ramp delay not supported\n",
+			rdev->desc->name);
+		return -EINVAL;
+	}
+	ramp_value = max77802_find_ramp_value(rdev, ramp_table_77802_2bit,
+				ARRAY_SIZE(ramp_table_77802_2bit), ramp_delay);
+
+	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+				  MAX77802_RAMP_RATE_MASK_2BIT,
+				  ramp_value << MAX77802_RAMP_RATE_SHIFT_2BIT);
+}
+
+/* For BUCK1, 6 */
+static int max77802_set_ramp_delay_4bit(struct regulator_dev *rdev,
+					    int ramp_delay)
+{
+	unsigned int ramp_value;
+
+	ramp_value = max77802_find_ramp_value(rdev, ramp_table_77802_4bit,
+				ARRAY_SIZE(ramp_table_77802_4bit), ramp_delay);
+
+	return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+				  MAX77802_RAMP_RATE_MASK_4BIT,
+				  ramp_value << MAX77802_RAMP_RATE_SHIFT_4BIT);
+}
+
+/*
+ * LDOs 3-7, 9-14, 18-26, 28, 29, 32-34, 1, 2, 8, 15, 17, 27, 30, 35 (all)
+ */
+static struct regulator_ops max77802_ldo_ops = {
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.is_enabled		= regulator_is_enabled_regmap,
+	.enable			= max77802_enable,
+	.disable		= regulator_disable_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.set_voltage_time_sel	= regulator_set_voltage_time_sel,
+	.set_suspend_mode	= max77802_ldo_set_suspend_mode,
+};
+
+/* BUCKS 1, 6 */
+static struct regulator_ops max77802_buck_16_dvs_ops = {
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.is_enabled		= regulator_is_enabled_regmap,
+	.enable			= max77802_enable,
+	.disable		= regulator_disable_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.set_voltage_time_sel	= regulator_set_voltage_time_sel,
+	.set_ramp_delay		= max77802_set_ramp_delay_4bit,
+	.set_suspend_disable	= max77802_buck_set_suspend_disable,
+};
+
+/* BUCKs 2-4, 5, 7-10 */
+static struct regulator_ops max77802_buck_dvs_ops = {
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.is_enabled		= regulator_is_enabled_regmap,
+	.enable			= max77802_enable,
+	.disable		= regulator_disable_regmap,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.set_voltage_time_sel	= regulator_set_voltage_time_sel,
+	.set_ramp_delay		= max77802_set_ramp_delay_2bit,
+	.set_suspend_disable	= max77802_buck_set_suspend_disable,
+};
+
+/* LDOs 3-7, 9-14, 18-26, 28, 29, 32-34 */
+#define regulator_77802_desc_p_ldo(num)	{				\
+	.name		= "LDO"#num,					\
+	.id		= MAX77802_LDO##num,				\
+	.ops		= &max77802_ldo_ops,				\
+	.type		= REGULATOR_VOLTAGE,				\
+	.owner		= THIS_MODULE,					\
+	.min_uV		= 800000,					\
+	.uV_step	= 50000,					\
+	.ramp_delay	= MAX77802_RAMP_DELAY,				\
+	.n_voltages	= 1 << 6,					\
+	.vsel_reg	= MAX77802_REG_LDO1CTRL1 + num - 1,		\
+	.vsel_mask	= MAX77802_VSEL_MASK,				\
+	.enable_reg	= MAX77802_REG_LDO1CTRL1 + num - 1,		\
+	.enable_mask	= MAX77802_OPMODE_MASK << MAX77802_OPMODE_SHIFT_LDO, \
+}
+
+/* LDOs 1, 2, 8, 15, 17, 27, 30, 35 */
+#define regulator_77802_desc_n_ldo(num)	{				\
+	.name		= "LDO"#num,					\
+	.id		= MAX77802_LDO##num,				\
+	.ops		= &max77802_ldo_ops,				\
+	.type		= REGULATOR_VOLTAGE,				\
+	.owner		= THIS_MODULE,					\
+	.min_uV		= 800000,					\
+	.uV_step	= 25000,					\
+	.ramp_delay	= MAX77802_RAMP_DELAY,				\
+	.n_voltages	= 1 << 6,					\
+	.vsel_reg	= MAX77802_REG_LDO1CTRL1 + num - 1,		\
+	.vsel_mask	= MAX77802_VSEL_MASK,				\
+	.enable_reg	= MAX77802_REG_LDO1CTRL1 + num - 1,		\
+	.enable_mask	= MAX77802_OPMODE_MASK << MAX77802_OPMODE_SHIFT_LDO, \
+}
+
+/* BUCKs 1, 6 */
+#define regulator_77802_desc_16_buck(num)	{			\
+	.name		= "BUCK"#num,					\
+	.id		= MAX77802_BUCK##num,				\
+	.ops		= &max77802_buck_16_dvs_ops,			\
+	.type		= REGULATOR_VOLTAGE,				\
+	.owner		= THIS_MODULE,					\
+	.min_uV		= 612500,					\
+	.uV_step	= 6250,						\
+	.ramp_delay	= MAX77802_RAMP_DELAY,				\
+	.n_voltages	= 1 << 8,					\
+	.vsel_reg	= MAX77802_REG_BUCK ## num ## DVS1,		\
+	.vsel_mask	= MAX77802_DVS_VSEL_MASK,			\
+	.enable_reg	= MAX77802_REG_BUCK ## num ## CTRL,		\
+	.enable_mask	= MAX77802_OPMODE_MASK,				\
+}
+
+/* BUCKS 2-4 */
+#define regulator_77802_desc_234_buck(num)	{			\
+	.name		= "BUCK"#num,					\
+	.id		= MAX77802_BUCK##num,				\
+	.ops		= &max77802_buck_dvs_ops,			\
+	.type		= REGULATOR_VOLTAGE,				\
+	.owner		= THIS_MODULE,					\
+	.min_uV		= 600000,					\
+	.uV_step	= 6250,						\
+	.ramp_delay	= MAX77802_RAMP_DELAY,				\
+	.n_voltages	= 0x91,						\
+	.vsel_reg	= MAX77802_REG_BUCK ## num ## DVS1,		\
+	.vsel_mask	= MAX77802_DVS_VSEL_MASK,			\
+	.enable_reg	= MAX77802_REG_BUCK ## num ## CTRL1,		\
+	.enable_mask	= MAX77802_OPMODE_MASK <<			\
+				MAX77802_OPMODE_BUCK234_SHIFT,		\
+}
+
+/* BUCK 5 */
+#define regulator_77802_desc_buck5(num)		{			\
+	.name		= "BUCK"#num,					\
+	.id		= MAX77802_BUCK##num,				\
+	.ops		= &max77802_buck_dvs_ops,			\
+	.type		= REGULATOR_VOLTAGE,				\
+	.owner		= THIS_MODULE,					\
+	.min_uV		= 750000,					\
+	.uV_step	= 50000,					\
+	.ramp_delay	= MAX77802_RAMP_DELAY,				\
+	.n_voltages	= 1 << 6,					\
+	.vsel_reg	= MAX77802_REG_BUCK5OUT,			\
+	.vsel_mask	= MAX77802_VSEL_MASK,				\
+	.enable_reg	= MAX77802_REG_BUCK5CTRL,			\
+	.enable_mask	= MAX77802_OPMODE_MASK,				\
+}
+
+/* BUCKs 7-10 */
+#define regulator_77802_desc_buck7_10(num)	{			\
+	.name		= "BUCK"#num,					\
+	.id		= MAX77802_BUCK##num,				\
+	.ops		= &max77802_buck_dvs_ops,			\
+	.type		= REGULATOR_VOLTAGE,				\
+	.owner		= THIS_MODULE,					\
+	.min_uV		= 750000,					\
+	.uV_step	= 50000,					\
+	.ramp_delay	= MAX77802_RAMP_DELAY,				\
+	.n_voltages	= 1 << 6,					\
+	.vsel_reg	= MAX77802_REG_BUCK7OUT + (num - 7) * 3,	\
+	.vsel_mask	= MAX77802_VSEL_MASK,				\
+	.enable_reg	= MAX77802_REG_BUCK7CTRL + (num - 7) * 3,	\
+	.enable_mask	= MAX77802_OPMODE_MASK,				\
+}
+
+static struct regulator_desc regulators[] = {
+	regulator_77802_desc_n_ldo(1),
+	regulator_77802_desc_n_ldo(2),
+	regulator_77802_desc_p_ldo(3),
+	regulator_77802_desc_p_ldo(4),
+	regulator_77802_desc_p_ldo(5),
+	regulator_77802_desc_p_ldo(6),
+	regulator_77802_desc_p_ldo(7),
+	regulator_77802_desc_n_ldo(8),
+	regulator_77802_desc_p_ldo(9),
+	regulator_77802_desc_p_ldo(10),
+	regulator_77802_desc_p_ldo(11),
+	regulator_77802_desc_p_ldo(12),
+	regulator_77802_desc_p_ldo(13),
+	regulator_77802_desc_p_ldo(14),
+	regulator_77802_desc_n_ldo(15),
+	regulator_77802_desc_n_ldo(17),
+	regulator_77802_desc_p_ldo(18),
+	regulator_77802_desc_p_ldo(19),
+	regulator_77802_desc_p_ldo(20),
+	regulator_77802_desc_p_ldo(21),
+	regulator_77802_desc_p_ldo(23),
+	regulator_77802_desc_p_ldo(24),
+	regulator_77802_desc_p_ldo(25),
+	regulator_77802_desc_p_ldo(26),
+	regulator_77802_desc_n_ldo(27),
+	regulator_77802_desc_p_ldo(28),
+	regulator_77802_desc_p_ldo(29),
+	regulator_77802_desc_n_ldo(30),
+	regulator_77802_desc_p_ldo(32),
+	regulator_77802_desc_p_ldo(33),
+	regulator_77802_desc_p_ldo(34),
+	regulator_77802_desc_n_ldo(35),
+	regulator_77802_desc_16_buck(1),
+	regulator_77802_desc_234_buck(2),
+	regulator_77802_desc_234_buck(3),
+	regulator_77802_desc_234_buck(4),
+	regulator_77802_desc_buck5(5),
+	regulator_77802_desc_16_buck(6),
+	regulator_77802_desc_buck7_10(7),
+	regulator_77802_desc_buck7_10(8),
+	regulator_77802_desc_buck7_10(9),
+	regulator_77802_desc_buck7_10(10),
+};
+
+#ifdef CONFIG_OF
+static int max77802_pmic_dt_parse_pdata(struct platform_device *pdev,
+					struct max77802_platform_data *pdata)
+{
+	struct max77802_dev *iodev = dev_get_drvdata(pdev->dev.parent);
+	struct device_node *pmic_np, *regulators_np;
+	struct max77802_regulator_data *rdata;
+	struct of_regulator_match rmatch;
+	unsigned int i;
+
+	pmic_np = iodev->dev->of_node;
+	regulators_np = of_get_child_by_name(pmic_np, "voltage-regulators");
+	if (!regulators_np) {
+		dev_err(&pdev->dev, "could not find regulators sub-node\n");
+		return -EINVAL;
+	}
+
+	pdata->num_regulators = ARRAY_SIZE(regulators);
+	rdata = devm_kzalloc(&pdev->dev, sizeof(*rdata) *
+			     pdata->num_regulators, GFP_KERNEL);
+	if (!rdata) {
+		of_node_put(regulators_np);
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < pdata->num_regulators; i++) {
+		rmatch.name = regulators[i].name;
+		rmatch.init_data = NULL;
+		rmatch.of_node = NULL;
+		if (of_regulator_match(&pdev->dev, regulators_np, &rmatch,
+				       1) != 1) {
+			dev_warn(&pdev->dev,
+				 "No matching regulator for '%s'\n", rmatch.name);
+			continue;
+		}
+		rdata[i].initdata = rmatch.init_data;
+		rdata[i].of_node = rmatch.of_node;
+		rdata[i].id = regulators[i].id;
+	}
+
+	pdata->regulators = rdata;
+	of_node_put(regulators_np);
+
+	return 0;
+}
+#else
+static int max77802_pmic_dt_parse_pdata(struct platform_device *pdev,
+					struct max77802_platform_data *pdata)
+{
+	return 0;
+}
+#endif /* CONFIG_OF */
+
+/**
+ * max77802_setup_gpios - init DVS-related GPIOs
+ *
+ * This function claims / initalizations GPIOs related to DVS if they are
+ * defined. This may have the effect of switching voltages if the
+ * pdata->buck_default_idx does not match the boot time state of pins.
+ */
+static int max77802_setup_gpios(struct device *dev,
+				struct max77802_platform_data *pdata)
+{
+	int buck_default_idx = pdata->buck_default_idx;
+	int ret;
+	int i;
+
+	/* Set all SELB high to avoid glitching while DVS is changing */
+	for (i = 0; i < ARRAY_SIZE(pdata->buck_gpio_selb); i++) {
+		int gpio = pdata->buck_gpio_selb[i];
+
+		/* OK if some GPIOs aren't defined */
+		if (!gpio_is_valid(gpio))
+			continue;
+
+		/* If a GPIO is valid, we'd better be able to claim it */
+		ret = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
+					    "max77802 selb");
+		if (ret) {
+			dev_err(dev, "can't claim gpio[%d]: %d\n", i, ret);
+			return ret;
+		}
+	}
+
+	/* Set our initial setting */
+	for (i = 0; i < ARRAY_SIZE(pdata->buck_gpio_dvs); i++) {
+		int gpio = pdata->buck_gpio_dvs[i];
+
+		/* OK if some GPIOs aren't defined */
+		if (!gpio_is_valid(gpio))
+			continue;
+
+		/* If a GPIO is valid, we'd better be able to claim it */
+		ret = devm_gpio_request(dev, gpio, "max77802 dvs");
+		if (ret) {
+			dev_err(dev, "can't claim gpio[%d]: %d\n", i, ret);
+			return ret;
+		}
+		gpio_direction_output(gpio, (buck_default_idx >> i) & 1);
+	}
+
+	/* Now set SELB low to take effect */
+	for (i = 0; i < ARRAY_SIZE(pdata->buck_gpio_selb); i++) {
+		int gpio = pdata->buck_gpio_selb[i];
+
+		if (gpio_is_valid(gpio))
+			gpio_set_value(gpio, 0);
+	}
+
+	return 0;
+}
+
+/**
+ * max77802_read_gpios - read the current state of the dvs GPIOs
+ *
+ * We call this function at bootup to detect what slot the firmware was
+ * using for the DVS GPIOs.  That way we can properly preserve the firmware's
+ * voltage settings
+ */
+static int max77802_read_gpios(struct max77802_platform_data *pdata)
+{
+	int buck_default_idx = pdata->buck_default_idx;
+	int result = 0;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(pdata->buck_gpio_dvs); i++) {
+		int gpio = pdata->buck_gpio_dvs[i];
+
+		/* OK if some GPIOs aren't defined; we'll use default */
+		if (!gpio_is_valid(gpio)) {
+			result |= buck_default_idx & (1 << i);
+			continue;
+		}
+
+		if (gpio_get_value_cansleep(gpio))
+			result |= 1 << i;
+	}
+
+	return result;
+}
+
+static inline bool max77802_is_dvs_buck(int id)
+{
+	/* on 77802 bucks 1-4, 6 are */
+	return ((id >= MAX77802_BUCK1 && id <= MAX77802_BUCK4) ||
+		(id == MAX77802_BUCK6));
+}
+
+static void max77802_copy_reg(struct device *dev, struct regmap *regmap,
+			      int from_reg, int to_reg)
+{
+	int val;
+	int ret;
+
+	if (from_reg == to_reg)
+		return;
+
+	ret = regmap_read(regmap, from_reg, &val);
+	if (!ret)
+		ret = regmap_write(regmap, to_reg, val);
+
+	if (ret)
+		dev_warn(dev, "Copy err %d => %d (%d)\n",
+			 from_reg, to_reg, ret);
+}
+
+static int max77802_pmic_probe(struct platform_device *pdev)
+{
+	struct max77802_dev *iodev = dev_get_drvdata(pdev->dev.parent);
+	struct max77802_platform_data *pdata = dev_get_platdata(iodev->dev);
+	struct max77802_regulator_prv *max77802;
+	int i, ret = 0;
+	struct regulator_config config = { };
+	unsigned int reg;
+	int buck_default_idx;
+	int buck_old_idx;
+
+	dev_dbg(&pdev->dev, "%s\n", __func__);
+
+	/* This is allocated by the MFD driver */
+	if (!pdata) {
+		dev_err(&pdev->dev, "no platform data found for regulator\n");
+		return -ENODEV;
+	}
+
+	max77802 = devm_kzalloc(&pdev->dev,
+				sizeof(struct max77802_regulator_prv),
+				GFP_KERNEL);
+	if (!max77802)
+		return -ENOMEM;
+
+	if (iodev->dev->of_node) {
+		ret = max77802_pmic_dt_parse_pdata(pdev, pdata);
+		if (ret)
+			return ret;
+	}
+
+	if (pdata->num_regulators != MAX77802_MAX_REGULATORS) {
+		dev_err(&pdev->dev,
+			"Invalid initial data for regulator's initialiation: " \
+			"expected %d, pdata/dt provided %d\n",
+			MAX77802_MAX_REGULATORS,
+			pdata->num_regulators);
+		return -EINVAL;
+	}
+
+	config.dev = &pdev->dev;
+	config.regmap = iodev->regmap;
+	config.driver_data = max77802;
+	platform_set_drvdata(pdev, max77802);
+
+	buck_default_idx = pdata->buck_default_idx;
+	buck_old_idx = max77802_read_gpios(pdata);
+
+	for (i = 0; i < MAX77802_MAX_REGULATORS; i++) {
+		struct regulator_dev *rdev;
+		int id = pdata->regulators[i].id;
+
+		config.init_data = pdata->regulators[i].initdata;
+		config.of_node = pdata->regulators[i].of_node;
+
+		max77802->opmode[id] = MAX77802_OPMODE_NORMAL;
+
+		if (max77802_is_dvs_buck(id)) {
+			/* Try to copy over data so we keep firmware settings */
+			reg = regulators[i].vsel_reg;
+			max77802_copy_reg(&pdev->dev, iodev->regmap,
+					  reg + buck_old_idx,
+					  reg + buck_default_idx);
+			regulators[i].vsel_reg += buck_default_idx;
+		}
+
+		rdev = devm_regulator_register(&pdev->dev,
+						&regulators[i], &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&pdev->dev,
+				"regulator init failed for %d\n", i);
+			return PTR_ERR(rdev);
+		}
+	}
+
+	ret = max77802_setup_gpios(&pdev->dev, pdata);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static const struct platform_device_id max77802_pmic_id[] = {
+	{"max77802-pmic", 0},
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, max77802_pmic_id);
+
+static struct platform_driver max77802_pmic_driver = {
+	.driver = {
+		.name = "max77802-pmic",
+		.owner = THIS_MODULE,
+	},
+	.probe = max77802_pmic_probe,
+	.id_table = max77802_pmic_id,
+};
+
+static int __init max77802_pmic_init(void)
+{
+	return platform_driver_register(&max77802_pmic_driver);
+}
+subsys_initcall(max77802_pmic_init);
+
+static void __exit max77802_pmic_cleanup(void)
+{
+	platform_driver_unregister(&max77802_pmic_driver);
+}
+module_exit(max77802_pmic_cleanup);
+
+MODULE_DESCRIPTION("MAXIM 77802 Regulator Driver");
+MODULE_AUTHOR("Simon Glass <sjg@chromium.org>");
+MODULE_LICENSE("GPL");