[PATCH 1/2] ISL6271A voltage regulator support.

[marek.vasut@gmail.com (Marek Vasut)]

Dne Po 7. ?ervna 2010 07:18:27 Marek Vasut napsal(a):
> This device is very simple, it supports only one LDO. This single LDO is
> programmed over I2C to 16 possible voltages.
> 
> Signed-off-by: Marek Vasut <marek.vasut@gmail.com>

I need to test this ... Cyril, will you do me the favour? I'll return that 
Zaurus to you, I was unable to compile kernel for it (I dunno what options to 
select and I don't feel like trying to figure out).

Also, see the comment below, if it doesn't boot for you, maybe adjust it (try 
setting it to 1, 2, 3).

btw. I made modification to 2/2 patch of this series, use the updated patchset.

Thanks!

> ---
>  drivers/regulator/Kconfig              |    6 +
>  drivers/regulator/Makefile             |    1 +
>  drivers/regulator/isl6271a-regulator.c |  202
> ++++++++++++++++++++++++++++++++ 3 files changed, 209 insertions(+), 0
> deletions(-)
>  create mode 100644 drivers/regulator/isl6271a-regulator.c
> 
> diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
> index 04f2e08..6772ca7 100644
> --- a/drivers/regulator/Kconfig
> +++ b/drivers/regulator/Kconfig
> @@ -201,5 +201,11 @@ config REGULATOR_88PM8607
>  	help
>  	  This driver supports 88PM8607 voltage regulator chips.
> 
> +config REGULATOR_ISL6271A
> +	tristate "Intersil ISL6271A Power regulator"
> +	depends on I2C
> +	help
> +	  This driver supports ISL6271A voltage regulator chip.
> +
>  endif
> 
> diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
> index 4e7feec..e2191bf 100644
> --- a/drivers/regulator/Makefile
> +++ b/drivers/regulator/Makefile
> @@ -31,5 +31,6 @@ obj-$(CONFIG_REGULATOR_AB3100) += ab3100.o
>  obj-$(CONFIG_REGULATOR_TPS65023) += tps65023-regulator.o
>  obj-$(CONFIG_REGULATOR_TPS6507X) += tps6507x-regulator.o
>  obj-$(CONFIG_REGULATOR_88PM8607) += 88pm8607.o
> +obj-$(CONFIG_REGULATOR_ISL6271A) += isl6271a-regulator.o
> 
>  ccflags-$(CONFIG_REGULATOR_DEBUG) += -DDEBUG
> diff --git a/drivers/regulator/isl6271a-regulator.c
> b/drivers/regulator/isl6271a-regulator.c new file mode 100644
> index 0000000..c6fd20f
> --- /dev/null
> +++ b/drivers/regulator/isl6271a-regulator.c
> @@ -0,0 +1,202 @@
> +/*
> + * isl6271a-regulator.c
> + *
> + * Support for Intersil ISL6271A voltage regulator
> + *
> + * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.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 version 2.
> + *
> + * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
> + * whether express or implied; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * General Public License for more details.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/err.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/driver.h>
> +#include <linux/regulator/machine.h>
> +#include <linux/i2c.h>
> +#include <linux/delay.h>
> +#include <linux/slab.h>
> +
> +/* Supported voltage values for regulators */
> +static const u16 core_buck_table[] = {
> +	850, 900, 950, 1000,
> +	1050, 1100, 1150, 1200,
> +	1250, 1300, 1350, 1400,
> +	1450, 1500, 1550, 1600,
> +};
> +
> +/* PMIC details */
> +struct isl_pmic {
> +	struct regulator_desc	desc;
> +	struct i2c_client	*client;
> +	struct regulator_dev	*rdev;
> +	struct mutex		mtx;
> +};
> +
> +static int isl6271a_get_voltage(struct regulator_dev *dev)
> +{
> +	struct isl_pmic *pmic = rdev_get_drvdata(dev);
> +	int idx, data;
> +
> +	mutex_lock(&pmic->mtx);
> +
> +	idx = i2c_smbus_read_byte_data(pmic->client, 0);
> +	if (idx < 0) {
> +		dev_err(&pmic->client->dev, "Error getting voltage\n");
> +		data = idx;
> +		goto out;
> +	}
> +
> +	data = core_buck_table[idx & 0xf];
> +
> +out:
> +	mutex_unlock(&pmic->mtx);
> +	return idx;
> +}
> +
> +static int isl6271a_set_voltage(struct regulator_dev *dev, int minuV, int
> maxuV) +{
> +	struct isl_pmic *pmic = rdev_get_drvdata(dev);
> +	int vsel, err;
> +	int pmic_minuV = core_buck_table[0];
> +	int pmic_maxuV = core_buck_table[ARRAY_SIZE(core_buck_table) - 1];
> +
> +	if (minuV < pmic_minuV || minuV > pmic_maxuV)
> +		return -EINVAL;
> +	if (maxuV < pmic_minuV || maxuV > pmic_maxuV)
> +		return -EINVAL;
> +
> +	for (vsel = 0; vsel < ARRAY_SIZE(core_buck_table); vsel++) {
> +		int uV = core_buck_table[vsel];
> +
> +		if (minuV <= uV && uV <= maxuV)
> +			break;
> +	}
> +
> +	if (vsel == ARRAY_SIZE(core_buck_table))
> +		return -EINVAL;
> +
> +	mutex_lock(&pmic->mtx);

maybe here we should adjust the vsel with slew-rate (page 9 of the datasheet):

vsel |= slew_rate << 4; // slew_rate is in range 0..3

> +
> +	err = i2c_smbus_write_byte_data(pmic->client, 0, vsel);
> +	if (err < 0)
> +		dev_err(&pmic->client->dev, "Error setting voltage\n");
> +
> +	mutex_unlock(&pmic->mtx);
> +	return err;
> +}
> +
> +static int isl6271a_list_voltage(struct regulator_dev *dev, unsigned
> selector) +{
> +	return core_buck_table[selector];
> +}
> +
> +static struct regulator_ops isl_core_ops = {
> +	.get_voltage	= isl6271a_get_voltage,
> +	.set_voltage	= isl6271a_set_voltage,
> +	.list_voltage	= isl6271a_list_voltage,
> +};
> +
> +static int __devinit isl6271a_probe(struct i2c_client *client,
> +				     const struct i2c_device_id *id)
> +{
> +	struct regulator_init_data *init_data	= client->dev.platform_data;
> +	struct isl_pmic *pmic;
> +	int err;
> +
> +	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
> +		return -EIO;
> +
> +	if (!init_data)
> +		return -EIO;
> +
> +	pmic = kzalloc(sizeof(struct isl_pmic), GFP_KERNEL);
> +	if (!pmic)
> +		return -ENOMEM;
> +
> +	pmic->client = client;
> +
> +	mutex_init(&pmic->mtx);
> +
> +	pmic->desc.name	= "Core Buck";
> +	pmic->desc.id	= 0;
> +	pmic->desc.n_voltages = ARRAY_SIZE(core_buck_table);
> +	pmic->desc.ops	= &isl_core_ops;
> +	pmic->desc.type	= REGULATOR_VOLTAGE;
> +	pmic->desc.owner = THIS_MODULE;
> +
> +	pmic->rdev = regulator_register(&pmic->desc, &client->dev,
> +					init_data, pmic);
> +	if (IS_ERR(pmic->rdev)) {
> +		dev_err(&client->dev, "failed to register %s\n",
> +			id->name);
> +		err = PTR_ERR(pmic->rdev);
> +		goto error;
> +	}
> +
> +	i2c_set_clientdata(client, pmic);
> +
> +	return 0;
> +
> +error:
> +	regulator_unregister(pmic->rdev);
> +
> +	kfree(pmic);
> +	return err;
> +}
> +
> +static int __devexit isl6271a_remove(struct i2c_client *client)
> +{
> +	struct isl_pmic *pmic = i2c_get_clientdata(client);
> +
> +	i2c_set_clientdata(client, NULL);
> +
> +	regulator_unregister(pmic->rdev);
> +
> +	kfree(pmic);
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id isl6271a_id[] = {
> +	{.name = "isl6271a", 0 },
> +	{ },
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, isl6271a_id);
> +
> +static struct i2c_driver isl6271a_i2c_driver = {
> +	.driver = {
> +		.name = "isl6271a",
> +		.owner = THIS_MODULE,
> +	},
> +	.probe = isl6271a_probe,
> +	.remove = __devexit_p(isl6271a_remove),
> +	.id_table = isl6271a_id,
> +};
> +
> +static int __init isl6271a_init(void)
> +{
> +	return i2c_add_driver(&isl6271a_i2c_driver);
> +}
> +
> +static void __exit isl6271a_cleanup(void)
> +{
> +	i2c_del_driver(&isl6271a_i2c_driver);
> +}
> +
> +subsys_initcall(isl6271a_init);
> +module_exit(isl6271a_cleanup);
> +
> +MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
> +MODULE_DESCRIPTION("Intersil ISL6271A voltage regulator driver");
> +MODULE_LICENSE("GPL v2");