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path: root/drivers/regulator/tps6238x0-regulator.c
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Diffstat (limited to 'drivers/regulator/tps6238x0-regulator.c')
-rw-r--r--drivers/regulator/tps6238x0-regulator.c488
1 files changed, 488 insertions, 0 deletions
diff --git a/drivers/regulator/tps6238x0-regulator.c b/drivers/regulator/tps6238x0-regulator.c
new file mode 100644
index 000000000000..880249627ab6
--- /dev/null
+++ b/drivers/regulator/tps6238x0-regulator.c
@@ -0,0 +1,488 @@
+/*
+ * tps6238x0-regulator.c -- TI tps623850/tps623860/tps623870
+ *
+ * Driver for processor core supply tps623850, tps623860 and tps623870
+ *
+ * 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/tps6238x0-regulator.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_MODE0 2
+#define REG_MODE1 3
+#define REG_CONTROL 4
+#define REG_EXCEPTION 5
+#define REG_RAMPCTRL 6
+#define REG_IOUT 7
+#define REG_CHIPID 8
+
+#define TPS6238X0_BASE_VOLTAGE 500000
+#define TPS6238X0_N_VOLTAGES 128
+#define TPS6238X0_MAX_VSET 2
+#define TPS6238X0_VOUT_MASK 0x7F
+
+/* tps 6238x0 chip information */
+struct tps6238x0_chip {
+ const char *name;
+ struct device *dev;
+ struct regulator_desc desc;
+ struct regulator_dev *rdev;
+ struct regmap *regmap;
+ int vsel_gpio;
+ int change_uv_per_us;
+ bool en_internal_pulldn;
+ bool en_discharge;
+ bool valid_gpios;
+ int lru_index[TPS6238X0_MAX_VSET];
+ int curr_vset_vsel[TPS6238X0_MAX_VSET];
+ 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 tps6238x0_chip *tps,
+ int req_vsel, int *vset_reg_id)
+{
+ int i;
+ bool found = false;
+ int new_vset_reg = tps->lru_index[1];
+ int found_index = 1;
+ for (i = 0; i < TPS6238X0_MAX_VSET; ++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 tps6238x0_get_voltage_sel(struct regulator_dev *dev)
+{
+ struct tps6238x0_chip *tps = rdev_get_drvdata(dev);
+ 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;
+ }
+ return data & TPS6238X0_VOUT_MASK;
+}
+
+static int tps6238x0_set_voltage(struct regulator_dev *dev,
+ int min_uV, int max_uV, unsigned *selector)
+{
+ struct tps6238x0_chip *tps = rdev_get_drvdata(dev);
+ int vsel;
+ int ret;
+ bool found = false;
+ int new_vset_id = tps->curr_vset_id;
+
+ if (min_uV >
+ ((TPS6238X0_BASE_VOLTAGE + (TPS6238X0_N_VOLTAGES - 1) * 10000)))
+ return -EINVAL;
+
+ if ((max_uV < min_uV) || (max_uV < TPS6238X0_BASE_VOLTAGE))
+ return -EINVAL;
+
+ vsel = DIV_ROUND_UP(min_uV - TPS6238X0_BASE_VOLTAGE, 10000);
+ if (selector)
+ *selector = (vsel & TPS6238X0_VOUT_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,
+ TPS6238X0_VOUT_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->vsel_gpio, new_vset_id & 0x1);
+ return 0;
+}
+
+static int tps6238x0_list_voltage(struct regulator_dev *dev,
+ unsigned selector)
+{
+ struct tps6238x0_chip *tps = rdev_get_drvdata(dev);
+
+ if ((selector < 0) || (selector >= tps->desc.n_voltages))
+ return -EINVAL;
+
+ return TPS6238X0_BASE_VOLTAGE + selector * 10000;
+}
+
+static int tps6238x0_regulator_enable_time(struct regulator_dev *rdev)
+{
+ return 300;
+}
+
+static int tps6238x0_set_voltage_time_sel(struct regulator_dev *rdev,
+ unsigned int old_selector, unsigned int new_selector)
+{
+ struct tps6238x0_chip *tps = rdev_get_drvdata(rdev);
+ int old_uV, new_uV;
+ old_uV = tps6238x0_list_voltage(rdev, old_selector);
+
+ if (old_uV < 0)
+ return old_uV;
+
+ new_uV = tps6238x0_list_voltage(rdev, new_selector);
+ if (new_uV < 0)
+ return new_uV;
+
+ return DIV_ROUND_UP(abs(old_uV - new_uV),
+ tps->change_uv_per_us);
+}
+
+static int tps6238x0_is_enable(struct regulator_dev *rdev)
+{
+ struct tps6238x0_chip *tps = rdev_get_drvdata(rdev);
+ 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;
+ }
+ return !!(data & BIT(7));
+}
+
+static int tps6238x0_enable(struct regulator_dev *rdev)
+{
+ struct tps6238x0_chip *tps = rdev_get_drvdata(rdev);
+ int ret;
+ int i;
+
+ /* Enable required VSET configuration */
+ for (i = 0; i < TPS6238X0_MAX_VSET; ++i) {
+ unsigned int en = 0;
+ if (tps->valid_gpios || (i == tps->curr_vset_id))
+ en = BIT(7);
+
+ ret = regmap_update_bits(tps->regmap, REG_VSET0 + i,
+ BIT(7), en);
+ if (ret < 0) {
+ dev_err(tps->dev, "%s() fails in updating reg %d\n",
+ __func__, REG_VSET0 + i);
+ return ret;
+ }
+ }
+ return ret;
+}
+
+static int tps6238x0_disable(struct regulator_dev *rdev)
+{
+ struct tps6238x0_chip *tps = rdev_get_drvdata(rdev);
+ int ret;
+ int i;
+
+ /* Disable required VSET configuration */
+ for (i = 0; i < TPS6238X0_MAX_VSET; ++i) {
+ ret = regmap_update_bits(tps->regmap, REG_VSET0 + i,
+ BIT(7), 0);
+ if (ret < 0) {
+ dev_err(tps->dev, "%s() fails in updating reg %d\n",
+ __func__, REG_VSET0 + i);
+ return ret;
+ }
+ }
+ return ret;
+}
+
+static struct regulator_ops tps6238x0_ops = {
+ .is_enabled = tps6238x0_is_enable,
+ .enable = tps6238x0_enable,
+ .disable = tps6238x0_disable,
+ .enable_time = tps6238x0_regulator_enable_time,
+ .set_voltage_time_sel = tps6238x0_set_voltage_time_sel,
+ .get_voltage_sel = tps6238x0_get_voltage_sel,
+ .set_voltage = tps6238x0_set_voltage,
+ .list_voltage = tps6238x0_list_voltage,
+};
+
+static int __devinit tps6238x0_configure(struct tps6238x0_chip *tps,
+ struct tps6238x0_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, 0xC0);
+ 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;
+ }
+
+ /* Enable required VSET configuration */
+ for (i = 0; i < TPS6238X0_MAX_VSET; ++i) {
+ unsigned int en = 0;
+ if (tps->valid_gpios || (i == tps->curr_vset_id))
+ en = BIT(7);
+
+ ret = regmap_update_bits(tps->regmap, REG_VSET0 + i,
+ BIT(7), en);
+ if (ret < 0) {
+ dev_err(tps->dev, "%s() fails in updating reg %d\n",
+ __func__, REG_VSET0 + i);
+ 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);
+ tps->change_uv_per_us = 312;
+ return ret;
+}
+
+static const struct regmap_config tps6238x0_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = REG_CHIPID,
+ .num_reg_defaults_raw = REG_CHIPID + 1,
+ .cache_type = REGCACHE_RBTREE,
+};
+
+static int __devinit tps6238x0_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct tps6238x0_regulator_platform_data *pdata;
+ struct regulator_dev *rdev;
+ struct tps6238x0_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_discharge = pdata->en_discharge;
+ tps->en_internal_pulldn = pdata->en_internal_pulldn;
+ tps->vsel_gpio = pdata->vsel_gpio;
+ tps->dev = &client->dev;
+
+ tps->desc.name = id->name;
+ tps->desc.id = 0;
+ tps->desc.n_voltages = TPS6238X0_N_VOLTAGES;
+ tps->desc.ops = &tps6238x0_ops;
+ tps->desc.type = REGULATOR_VOLTAGE;
+ tps->desc.owner = THIS_MODULE;
+ tps->regmap = devm_regmap_init_i2c(client, &tps6238x0_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->vsel_def_state & 1);
+ tps->lru_index[0] = tps->curr_vset_id;
+ tps->valid_gpios = false;
+
+ if (gpio_is_valid(tps->vsel_gpio)) {
+ int gpio_flag;
+ gpio_flag = (tps->curr_vset_id) ?
+ GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
+ ret = gpio_request_one(tps->vsel_gpio,
+ gpio_flag, "tps6238x0-vsel0");
+ if (ret) {
+ dev_err(&client->dev,
+ "Err: Could not obtain vsel GPIO %d: %d\n",
+ tps->vsel_gpio, ret);
+ return ret;
+ }
+ 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 < TPS6238X0_MAX_VSET; ++i)
+ tps->lru_index[i] = i;
+ tps->lru_index[0] = tps->curr_vset_id;
+ tps->lru_index[tps->curr_vset_id] = 0;
+ }
+
+ ret = tps6238x0_configure(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->init_data, tps);
+ 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->vsel_gpio))
+ gpio_free(tps->vsel_gpio);
+
+ return ret;
+}
+
+/**
+ * tps6238x0_remove - tps62360 driver i2c remove handler
+ * @client: i2c driver client device structure
+ *
+ * Unregister TPS driver as an i2c client device driver
+ */
+static int __devexit tps6238x0_remove(struct i2c_client *client)
+{
+ struct tps6238x0_chip *tps = i2c_get_clientdata(client);
+
+ if (gpio_is_valid(tps->vsel_gpio))
+ gpio_free(tps->vsel_gpio);
+
+ regulator_unregister(tps->rdev);
+ return 0;
+}
+
+static void tps6238x0_shutdown(struct i2c_client *client)
+{
+ struct tps6238x0_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 tps6238x0_id[] = {
+ {.name = "tps623850", },
+ {.name = "tps623860", },
+ {.name = "tps623870", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(i2c, tps6238x0_id);
+
+static struct i2c_driver tps6238x0_i2c_driver = {
+ .driver = {
+ .name = "tps6238x0",
+ .owner = THIS_MODULE,
+ },
+ .probe = tps6238x0_probe,
+ .remove = __devexit_p(tps6238x0_remove),
+ .shutdown = tps6238x0_shutdown,
+ .id_table = tps6238x0_id,
+};
+
+static int __init tps6238x0_init(void)
+{
+ return i2c_add_driver(&tps6238x0_i2c_driver);
+}
+subsys_initcall(tps6238x0_init);
+
+static void __exit tps6238x0_cleanup(void)
+{
+ i2c_del_driver(&tps6238x0_i2c_driver);
+}
+module_exit(tps6238x0_cleanup);
+
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_DESCRIPTION("TPS623850/TPS623860/TPS623870 voltage regulator driver");
+MODULE_LICENSE("GPL v2");