| /* |
| * 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/slab.h> |
| #include <linux/regulator/max8649.h> |
| #include <linux/regmap.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 device *dev; |
| struct regmap *regmap; |
| |
| 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 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 int val; |
| unsigned char data; |
| int ret; |
| |
| ret = regmap_read(info->regmap, info->vol_reg, &val); |
| if (ret != 0) |
| return ret; |
| data = (unsigned char)val & MAX8649_VOL_MASK; |
| return max8649_list_voltage(rdev, data); |
| } |
| |
| static int max8649_set_voltage(struct regulator_dev *rdev, |
| int min_uV, int max_uV, unsigned *selector) |
| { |
| 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 = DIV_ROUND_UP(min_uV - MAX8649_DCDC_VMIN, MAX8649_DCDC_STEP); |
| mask = MAX8649_VOL_MASK; |
| *selector = data & mask; |
| |
| return regmap_update_bits(info->regmap, 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 regmap_update_bits(info->regmap, 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 regmap_update_bits(info->regmap, 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); |
| unsigned int val; |
| int ret; |
| |
| ret = regmap_read(info->regmap, MAX8649_CONTROL, &val); |
| if (ret != 0) |
| return ret; |
| return !((unsigned char)val & 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; |
| unsigned int val; |
| |
| /* get voltage */ |
| ret = regmap_read(info->regmap, info->vol_reg, &val); |
| if (ret != 0) |
| return ret; |
| val &= MAX8649_VOL_MASK; |
| voltage = max8649_list_voltage(rdev, (unsigned char)ret); /* uV */ |
| |
| /* get rate */ |
| ret = regmap_read(info->regmap, MAX8649_RAMP, &val); |
| if (ret != 0) |
| return ret; |
| ret = (val & MAX8649_RAMP_MASK) >> 5; |
| rate = (32 * 1000) >> ret; /* uV/uS */ |
| |
| return DIV_ROUND_UP(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: |
| regmap_update_bits(info->regmap, info->vol_reg, MAX8649_FORCE_PWM, |
| MAX8649_FORCE_PWM); |
| break; |
| case REGULATOR_MODE_NORMAL: |
| regmap_update_bits(info->regmap, 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); |
| unsigned int val; |
| int ret; |
| |
| ret = regmap_read(info->regmap, info->vol_reg, &val); |
| if (ret != 0) |
| return ret; |
| if (val & 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 struct regmap_config max8649_regmap_config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| }; |
| |
| 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 int val; |
| 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->regmap = regmap_init_i2c(client, &max8649_regmap_config); |
| if (IS_ERR(info->regmap)) { |
| ret = PTR_ERR(info->regmap); |
| dev_err(&client->dev, "Failed to allocate register map: %d\n", ret); |
| goto fail; |
| } |
| |
| info->dev = &client->dev; |
| 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 = regmap_read(info->regmap, MAX8649_CHIP_ID1, &val); |
| 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", val); |
| |
| /* enable VID0 & VID1 */ |
| regmap_update_bits(info->regmap, MAX8649_CONTROL, MAX8649_VID_MASK, 0); |
| |
| /* enable/disable external clock synchronization */ |
| info->extclk = pdata->extclk; |
| data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0; |
| regmap_update_bits(info->regmap, info->vol_reg, MAX8649_SYNC_EXTCLK, data); |
| if (info->extclk) { |
| /* set external clock frequency */ |
| info->extclk_freq = pdata->extclk_freq; |
| regmap_update_bits(info->regmap, MAX8649_SYNC, MAX8649_EXT_MASK, |
| info->extclk_freq << 6); |
| } |
| |
| if (pdata->ramp_timing) { |
| info->ramp_timing = pdata->ramp_timing; |
| regmap_update_bits(info->regmap, MAX8649_RAMP, MAX8649_RAMP_MASK, |
| info->ramp_timing << 5); |
| } |
| |
| info->ramp_down = pdata->ramp_down; |
| if (info->ramp_down) { |
| regmap_update_bits(info->regmap, MAX8649_RAMP, MAX8649_RAMP_DOWN, |
| MAX8649_RAMP_DOWN); |
| } |
| |
| info->regulator = regulator_register(&dcdc_desc, &client->dev, |
| pdata->regulator, info, NULL); |
| 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: |
| regmap_exit(info->regmap); |
| fail: |
| 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); |
| regmap_exit(info->regmap); |
| kfree(info); |
| } |
| |
| 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"); |
| |