diff options
Diffstat (limited to 'drivers/regulator/tps62360-regulator.c')
| -rw-r--r-- | drivers/regulator/tps62360-regulator.c | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/drivers/regulator/tps62360-regulator.c b/drivers/regulator/tps62360-regulator.c new file mode 100644 index 000000000000..e2ec73068ee2 --- /dev/null +++ b/drivers/regulator/tps62360-regulator.c @@ -0,0 +1,472 @@ +/* + * tps62360.c -- TI tps62360 + * + * Driver for processor core supply tps62360 and tps62361B + * + * Copyright (c) 2012, NVIDIA Corporation. + * + * Author: Laxman Dewangan <ldewangan@nvidia.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. + * + * 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/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/regulator/tps62360.h> +#include <linux/gpio.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/regmap.h> + +/* Register definitions */ +#define REG_VSET0 0 +#define REG_VSET1 1 +#define REG_VSET2 2 +#define REG_VSET3 3 +#define REG_CONTROL 4 +#define REG_TEMP 5 +#define REG_RAMPCTRL 6 +#define REG_CHIPID 8 + +enum chips {TPS62360, TPS62361}; + +#define TPS62360_BASE_VOLTAGE 770 +#define TPS62360_N_VOLTAGES 64 + +#define TPS62361_BASE_VOLTAGE 500 +#define TPS62361_N_VOLTAGES 128 + +/* tps 62360 chip information */ +struct tps62360_chip { + const char *name; + struct device *dev; + struct regulator_desc desc; + struct i2c_client *client; + struct regulator_dev *rdev; + struct regmap *regmap; + int chip_id; + int vsel0_gpio; + int vsel1_gpio; + int voltage_base; + u8 voltage_reg_mask; + bool en_internal_pulldn; + bool en_force_pwm; + bool en_discharge; + bool valid_gpios; + int lru_index[4]; + int curr_vset_vsel[4]; + int curr_vset_id; +}; + +/* + * find_voltage_set_register: Find new voltage configuration register + * (VSET) id. + * The finding of the new VSET register will be based on the LRU mechanism. + * Each VSET register will have different voltage configured . This + * Function will look if any of the VSET register have requested voltage set + * or not. + * - If it is already there then it will make that register as most + * recently used and return as found so that caller need not to set + * the VSET register but need to set the proper gpios to select this + * VSET register. + * - If requested voltage is not found then it will use the least + * recently mechanism to get new VSET register for new configuration + * and will return not_found so that caller need to set new VSET + * register and then gpios (both). + */ +static bool find_voltage_set_register(struct tps62360_chip *tps, + int req_vsel, int *vset_reg_id) +{ + int i; + bool found = false; + int new_vset_reg = tps->lru_index[3]; + int found_index = 3; + for (i = 0; i < 4; ++i) { + if (tps->curr_vset_vsel[tps->lru_index[i]] == req_vsel) { + new_vset_reg = tps->lru_index[i]; + found_index = i; + found = true; + goto update_lru_index; + } + } + +update_lru_index: + for (i = found_index; i > 0; i--) + tps->lru_index[i] = tps->lru_index[i - 1]; + + tps->lru_index[0] = new_vset_reg; + *vset_reg_id = new_vset_reg; + return found; +} + +static int tps62360_dcdc_get_voltage(struct regulator_dev *dev) +{ + struct tps62360_chip *tps = rdev_get_drvdata(dev); + int vsel; + unsigned int data; + int ret; + + ret = regmap_read(tps->regmap, REG_VSET0 + tps->curr_vset_id, &data); + if (ret < 0) { + dev_err(tps->dev, "%s: Error in reading register %d\n", + __func__, REG_VSET0 + tps->curr_vset_id); + return ret; + } + vsel = (int)data & tps->voltage_reg_mask; + return (tps->voltage_base + vsel * 10) * 1000; +} + +static int tps62360_dcdc_set_voltage(struct regulator_dev *dev, + int min_uV, int max_uV, unsigned *selector) +{ + struct tps62360_chip *tps = rdev_get_drvdata(dev); + int vsel; + int ret; + bool found = false; + int new_vset_id = tps->curr_vset_id; + + if (max_uV < min_uV) + return -EINVAL; + + if (min_uV > + ((tps->voltage_base + (tps->desc.n_voltages - 1) * 10) * 1000)) + return -EINVAL; + + if (max_uV < tps->voltage_base * 1000) + return -EINVAL; + + vsel = DIV_ROUND_UP(min_uV - (tps->voltage_base * 1000), 10000); + if (selector) + *selector = (vsel & tps->voltage_reg_mask); + + /* + * If gpios are available to select the VSET register then least + * recently used register for new configuration. + */ + if (tps->valid_gpios) + found = find_voltage_set_register(tps, vsel, &new_vset_id); + + if (!found) { + ret = regmap_update_bits(tps->regmap, REG_VSET0 + new_vset_id, + tps->voltage_reg_mask, vsel); + if (ret < 0) { + dev_err(tps->dev, "%s: Error in updating register %d\n", + __func__, REG_VSET0 + new_vset_id); + return ret; + } + tps->curr_vset_id = new_vset_id; + tps->curr_vset_vsel[new_vset_id] = vsel; + } + + /* Select proper VSET register vio gpios */ + if (tps->valid_gpios) { + gpio_set_value_cansleep(tps->vsel0_gpio, + new_vset_id & 0x1); + gpio_set_value_cansleep(tps->vsel1_gpio, + (new_vset_id >> 1) & 0x1); + } + return 0; +} + +static int tps62360_dcdc_list_voltage(struct regulator_dev *dev, + unsigned selector) +{ + struct tps62360_chip *tps = rdev_get_drvdata(dev); + + if (selector >= tps->desc.n_voltages) + return -EINVAL; + return (tps->voltage_base + selector * 10) * 1000; +} + +static struct regulator_ops tps62360_dcdc_ops = { + .get_voltage = tps62360_dcdc_get_voltage, + .set_voltage = tps62360_dcdc_set_voltage, + .list_voltage = tps62360_dcdc_list_voltage, +}; + +static int tps62360_init_force_pwm(struct tps62360_chip *tps, + struct tps62360_regulator_platform_data *pdata, + int vset_id) +{ + unsigned int data; + int ret; + ret = regmap_read(tps->regmap, REG_VSET0 + vset_id, &data); + if (ret < 0) { + dev_err(tps->dev, "%s() fails in writing reg %d\n", + __func__, REG_VSET0 + vset_id); + return ret; + } + tps->curr_vset_vsel[vset_id] = data & tps->voltage_reg_mask; + if (pdata->en_force_pwm) + data |= BIT(7); + else + data &= ~BIT(7); + ret = regmap_write(tps->regmap, REG_VSET0 + vset_id, data); + if (ret < 0) + dev_err(tps->dev, "%s() fails in writing reg %d\n", + __func__, REG_VSET0 + vset_id); + return ret; +} + +static int tps62360_init_dcdc(struct tps62360_chip *tps, + struct tps62360_regulator_platform_data *pdata) +{ + int ret; + int i; + + /* Initailize internal pull up/down control */ + if (tps->en_internal_pulldn) + ret = regmap_write(tps->regmap, REG_CONTROL, 0xE0); + else + ret = regmap_write(tps->regmap, REG_CONTROL, 0x0); + if (ret < 0) { + dev_err(tps->dev, "%s() fails in writing reg %d\n", + __func__, REG_CONTROL); + return ret; + } + + /* Initailize force PWM mode */ + if (tps->valid_gpios) { + for (i = 0; i < 4; ++i) { + ret = tps62360_init_force_pwm(tps, pdata, i); + if (ret < 0) + return ret; + } + } else { + ret = tps62360_init_force_pwm(tps, pdata, tps->curr_vset_id); + if (ret < 0) + return ret; + } + + /* Reset output discharge path to reduce power consumption */ + ret = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), 0); + if (ret < 0) + dev_err(tps->dev, "%s() fails in updating reg %d\n", + __func__, REG_RAMPCTRL); + return ret; +} + +static const struct regmap_config tps62360_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + +static int __devinit tps62360_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct tps62360_regulator_platform_data *pdata; + struct regulator_dev *rdev; + struct tps62360_chip *tps; + int ret; + int i; + + pdata = client->dev.platform_data; + if (!pdata) { + dev_err(&client->dev, "%s() Err: Platform data not found\n", + __func__); + return -EIO; + } + + tps = devm_kzalloc(&client->dev, sizeof(*tps), GFP_KERNEL); + if (!tps) { + dev_err(&client->dev, "%s() Err: Memory allocation fails\n", + __func__); + return -ENOMEM; + } + + tps->en_force_pwm = pdata->en_force_pwm; + tps->en_discharge = pdata->en_discharge; + tps->en_internal_pulldn = pdata->en_internal_pulldn; + tps->vsel0_gpio = pdata->vsel0_gpio; + tps->vsel1_gpio = pdata->vsel1_gpio; + tps->client = client; + tps->dev = &client->dev; + tps->name = id->name; + tps->voltage_base = (id->driver_data == TPS62360) ? + TPS62360_BASE_VOLTAGE : TPS62361_BASE_VOLTAGE; + tps->voltage_reg_mask = (id->driver_data == TPS62360) ? 0x3F : 0x7F; + + tps->desc.name = id->name; + tps->desc.id = 0; + tps->desc.n_voltages = (id->driver_data == TPS62360) ? + TPS62360_N_VOLTAGES : TPS62361_N_VOLTAGES; + tps->desc.ops = &tps62360_dcdc_ops; + tps->desc.type = REGULATOR_VOLTAGE; + tps->desc.owner = THIS_MODULE; + tps->regmap = regmap_init_i2c(client, &tps62360_regmap_config); + if (IS_ERR(tps->regmap)) { + ret = PTR_ERR(tps->regmap); + dev_err(&client->dev, "%s() Err: Failed to allocate register" + "map: %d\n", __func__, ret); + return ret; + } + i2c_set_clientdata(client, tps); + + tps->curr_vset_id = (pdata->vsel1_def_state & 1) * 2 + + (pdata->vsel0_def_state & 1); + tps->lru_index[0] = tps->curr_vset_id; + tps->valid_gpios = false; + + if (gpio_is_valid(tps->vsel0_gpio) && gpio_is_valid(tps->vsel1_gpio)) { + ret = gpio_request(tps->vsel0_gpio, "tps62360-vsel0"); + if (ret) { + dev_err(&client->dev, + "Err: Could not obtain vsel0 GPIO %d: %d\n", + tps->vsel0_gpio, ret); + goto err_gpio0; + } + ret = gpio_direction_output(tps->vsel0_gpio, + pdata->vsel0_def_state); + if (ret) { + dev_err(&client->dev, "Err: Could not set direction of" + "vsel0 GPIO %d: %d\n", tps->vsel0_gpio, ret); + gpio_free(tps->vsel0_gpio); + goto err_gpio0; + } + + ret = gpio_request(tps->vsel1_gpio, "tps62360-vsel1"); + if (ret) { + dev_err(&client->dev, + "Err: Could not obtain vsel1 GPIO %d: %d\n", + tps->vsel1_gpio, ret); + goto err_gpio1; + } + ret = gpio_direction_output(tps->vsel1_gpio, + pdata->vsel1_def_state); + if (ret) { + dev_err(&client->dev, "Err: Could not set direction of" + "vsel1 GPIO %d: %d\n", tps->vsel1_gpio, ret); + gpio_free(tps->vsel1_gpio); + goto err_gpio1; + } + tps->valid_gpios = true; + + /* + * Initialize the lru index with vset_reg id + * The index 0 will be most recently used and + * set with the tps->curr_vset_id */ + for (i = 0; i < 4; ++i) + tps->lru_index[i] = i; + tps->lru_index[0] = tps->curr_vset_id; + tps->lru_index[tps->curr_vset_id] = 0; + } + + ret = tps62360_init_dcdc(tps, pdata); + if (ret < 0) { + dev_err(tps->dev, "%s() Err: Init fails with = %d\n", + __func__, ret); + goto err_init; + } + + /* Register the regulators */ + rdev = regulator_register(&tps->desc, &client->dev, + &pdata->reg_init_data, tps, NULL); + if (IS_ERR(rdev)) { + dev_err(tps->dev, "%s() Err: Failed to register %s\n", + __func__, id->name); + ret = PTR_ERR(rdev); + goto err_init; + } + + tps->rdev = rdev; + return 0; + +err_init: + if (gpio_is_valid(tps->vsel1_gpio)) + gpio_free(tps->vsel1_gpio); +err_gpio1: + if (gpio_is_valid(tps->vsel0_gpio)) + gpio_free(tps->vsel0_gpio); +err_gpio0: + regmap_exit(tps->regmap); + return ret; +} + +/** + * tps62360_remove - tps62360 driver i2c remove handler + * @client: i2c driver client device structure + * + * Unregister TPS driver as an i2c client device driver + */ +static int __devexit tps62360_remove(struct i2c_client *client) +{ + struct tps62360_chip *tps = i2c_get_clientdata(client); + + if (gpio_is_valid(tps->vsel1_gpio)) + gpio_free(tps->vsel1_gpio); + + if (gpio_is_valid(tps->vsel0_gpio)) + gpio_free(tps->vsel0_gpio); + + regulator_unregister(tps->rdev); + regmap_exit(tps->regmap); + return 0; +} + +static void tps62360_shutdown(struct i2c_client *client) +{ + struct tps62360_chip *tps = i2c_get_clientdata(client); + int st; + + if (!tps->en_discharge) + return; + + /* Configure the output discharge path */ + st = regmap_update_bits(tps->regmap, REG_RAMPCTRL, BIT(2), BIT(2)); + if (st < 0) + dev_err(tps->dev, "%s() fails in updating reg %d\n", + __func__, REG_RAMPCTRL); +} + +static const struct i2c_device_id tps62360_id[] = { + {.name = "tps62360", .driver_data = TPS62360}, + {.name = "tps62361", .driver_data = TPS62361}, + {}, +}; + +MODULE_DEVICE_TABLE(i2c, tps62360_id); + +static struct i2c_driver tps62360_i2c_driver = { + .driver = { + .name = "tps62360", + .owner = THIS_MODULE, + }, + .probe = tps62360_probe, + .remove = __devexit_p(tps62360_remove), + .shutdown = tps62360_shutdown, + .id_table = tps62360_id, +}; + +static int __init tps62360_init(void) +{ + return i2c_add_driver(&tps62360_i2c_driver); +} +subsys_initcall(tps62360_init); + +static void __exit tps62360_cleanup(void) +{ + i2c_del_driver(&tps62360_i2c_driver); +} +module_exit(tps62360_cleanup); + +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_DESCRIPTION("TPS62360 voltage regulator driver"); +MODULE_LICENSE("GPL v2"); |