diff options
Diffstat (limited to 'drivers/regulator/max8952_grande.c')
| -rw-r--r-- | drivers/regulator/max8952_grande.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/drivers/regulator/max8952_grande.c b/drivers/regulator/max8952_grande.c new file mode 100644 index 0000000..dad8a8e --- /dev/null +++ b/drivers/regulator/max8952_grande.c @@ -0,0 +1,258 @@ +/* + * max8952.c - Voltage and current regulation for the Maxim 8952 + * + * Copyright (C) 2010 Samsung Electronics + * MyungJoo Ham <myungjoo.ham@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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/max8952.h> +#include <linux/mutex.h> +#include <linux/gpio.h> +#include <linux/io.h> +#include <linux/slab.h> + +/* Registers */ +enum { + MAX8952_REG_MODE0, + MAX8952_REG_MODE1, + MAX8952_REG_MODE2, + MAX8952_REG_MODE3, + MAX8952_REG_CONTROL, + MAX8952_REG_SYNC, + MAX8952_REG_RAMP, + MAX8952_REG_CHIP_ID1, + MAX8952_REG_CHIP_ID2, +}; + +struct max8952_data { + struct i2c_client *client; + struct device *dev; + struct mutex mutex; + struct max8952_platform_data *pdata; + struct regulator_dev *rdev; + + bool vid0; + bool vid1; + bool en; +}; + +static int max8952_read_reg(struct max8952_data *max8952, u8 reg) +{ + int ret = i2c_smbus_read_byte_data(max8952->client, reg); + if (ret > 0) + ret &= 0xff; + + return ret; +} + +static int max8952_write_reg(struct max8952_data *max8952, + u8 reg, u8 value) +{ + return i2c_smbus_write_byte_data(max8952->client, reg, value); +} + +static int max8952_voltage(struct max8952_data *max8952, u8 mode) +{ + return (max8952->pdata->dvs_mode[mode] * 10 + 770) * 1000; +} + +static int max8952_list_voltage(struct regulator_dev *rdev, + unsigned int selector) +{ + struct max8952_data *max8952 = rdev_get_drvdata(rdev); + + if (rdev_get_id(rdev) != 0) + return -EINVAL; + + return max8952_voltage(max8952, selector); +} + +static int max8952_is_enabled(struct regulator_dev *rdev) +{ + struct max8952_data *max8952 = rdev_get_drvdata(rdev); + return max8952->en; +} + +static int max8952_enable(struct regulator_dev *rdev) +{ + struct max8952_data *max8952 = rdev_get_drvdata(rdev); + + /* If not valid, assume "ALWAYS_HIGH" */ + if (gpio_is_valid(max8952->pdata->gpio_en)) + gpio_set_value(max8952->pdata->gpio_en, 1); + + max8952->en = true; + return 0; +} + +static int max8952_disable(struct regulator_dev *rdev) +{ + struct max8952_data *max8952 = rdev_get_drvdata(rdev); + + /* If not valid, assume "ALWAYS_HIGH" -> not permitted */ + if (gpio_is_valid(max8952->pdata->gpio_en)) + gpio_set_value(max8952->pdata->gpio_en, 0); + else + return -EPERM; + + max8952->en = false; + return 0; +} + +static int max8952_get_voltage(struct regulator_dev *rdev) +{ + struct max8952_data *max8952 = rdev_get_drvdata(rdev); + u8 vid = 0; + + if (max8952->vid0) + vid += 1; + if (max8952->vid1) + vid += 2; + + return max8952_voltage(max8952, vid); +} + +static int max8952_set_voltage(struct regulator_dev *rdev, + int min_uV, int max_uV, unsigned *selector) +{ + struct max8952_data *max8952 = rdev_get_drvdata(rdev); + s8 vid = -1, i; + + if (!gpio_is_valid(max8952->pdata->gpio_vid0) || + !gpio_is_valid(max8952->pdata->gpio_vid1)) { + /* DVS not supported */ + return -EPERM; + } + + for (i = 0; i < MAX8952_NUM_DVS_MODE; i++) { + int volt = max8952_voltage(max8952, i); + + /* Set the voltage as low as possible within the range */ + if (volt <= max_uV && volt >= min_uV) + if (vid == -1 || max8952_voltage(max8952, vid) > volt) + vid = i; + } + + if (vid >= 0 && vid < MAX8952_NUM_DVS_MODE) { + max8952->vid0 = (vid % 2 == 1); + max8952->vid1 = (((vid >> 1) % 2) == 1); + *selector = vid; + gpio_set_value(max8952->pdata->gpio_vid0, max8952->vid0); + gpio_set_value(max8952->pdata->gpio_vid1, max8952->vid1); + } else + return -EINVAL; + + return 0; +} + +static struct regulator_ops max8952_ops = { + .list_voltage = max8952_list_voltage, + .is_enabled = max8952_is_enabled, + .enable = max8952_enable, + .disable = max8952_disable, + .get_voltage = max8952_get_voltage, + .set_voltage = max8952_set_voltage, + .set_suspend_disable = max8952_disable, +}; + +static struct regulator_desc regulator = { + .name = "MAX8952_VOUT", + .id = 0, + .n_voltages = MAX8952_NUM_DVS_MODE, + .ops = &max8952_ops, + .type = REGULATOR_VOLTAGE, + .owner = THIS_MODULE, +}; + +static int __devinit max8952_pmic_probe(struct i2c_client *client, + const struct i2c_device_id *i2c_id) +{ + struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); + struct max8952_platform_data *pdata = client->dev.platform_data; + struct max8952_data *max8952; + + int ret = 0, err = 0; + int readbyte; + + max8952 = kzalloc(sizeof(struct max8952_data), GFP_KERNEL); + if (!max8952) + return -ENOMEM; + + max8952->client = client; + max8952->dev = &client->dev; + max8952->pdata = pdata; + mutex_init(&max8952->mutex); + + max8952_write_reg(max8952, MAX8952_REG_MODE3, 0x2B); + readbyte = max8952_read_reg(max8952, MAX8952_REG_MODE3); + printk(KERN_DEBUG "%s, readbyte : 0x%2x\n", __func__, readbyte); + + i2c_set_clientdata(client, max8952); + + return 0; + +err_reg: + kfree(max8952); + return ret; +} + +static int __devexit max8952_pmic_remove(struct i2c_client *client) +{ + struct max8952_data *max8952 = i2c_get_clientdata(client); + struct max8952_platform_data *pdata = max8952->pdata; + struct regulator_dev *rdev = max8952->rdev; + + kfree(max8952); + return 0; +} + +static const struct i2c_device_id max8952_ids[] = { + { "max8952_grande", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(i2c, max8952_ids); + +static struct i2c_driver max8952_pmic_driver = { + .probe = max8952_pmic_probe, + .remove = __devexit_p(max8952_pmic_remove), + .driver = { + .name = "max8952_grande", + }, + .id_table = max8952_ids, +}; + +static int __init max8952_pmic_init(void) +{ + return i2c_add_driver(&max8952_pmic_driver); +} +subsys_initcall(max8952_pmic_init); + +static void __exit max8952_pmic_exit(void) +{ + i2c_del_driver(&max8952_pmic_driver); +} +module_exit(max8952_pmic_exit); + +MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver"); +MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); +MODULE_LICENSE("GPL"); |