regulator: TPS6238X0: Add tps6238X0 regulator driver
Laxman Dewangan [Fri, 4 May 2012 19:56:56 +0000 (00:56 +0530)]
The regulator module consists of 1 DCDC. The output voltage
is configurable and is meant for supply power to the core
voltage of Soc.

Change-Id: Ic62d100a588f7b6f1b30c11fd44a925c97393069
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/100653
Reviewed-by: Automatic_Commit_Validation_User
Tested-by: Pradeep Goudagunta <pgoudagunta@nvidia.com>
Reviewed-by: Bitan Biswas <bbiswas@nvidia.com>

drivers/regulator/Kconfig
drivers/regulator/Makefile
drivers/regulator/tps6238x0-regulator.c [new file with mode: 0644]
include/linux/regulator/tps6238x0-regulator.h [new file with mode: 0644]

index d3cb8e6..8d7161b 100644 (file)
@@ -345,6 +345,16 @@ config REGULATOR_TPS62360
          high-frequency synchronous step down dc-dc converter optimized
          for battery-powered portable applications.
 
+config REGULATOR_TPS6238X0
+       tristate "TI TPS623850/TPS623860/TPS623870 Power Regulator"
+       depends on I2C
+       select REGMAP_I2C
+       help
+         This driver supports TPS6238X0 voltage regulator chip. This
+         regulator is meant for processor core supply. This chip is
+         high-frequency synchronous step down dc-dc converter optimized
+         for battery-powered portable applications.
+
 config REGULATOR_AAT2870
        tristate "AnalogicTech AAT2870 Regulators"
        depends on MFD_AAT2870_CORE
index 4fc5c3f..7cca6bd 100644 (file)
@@ -52,6 +52,7 @@ obj-$(CONFIG_REGULATOR_AB8500)        += ab8500.o
 obj-$(CONFIG_REGULATOR_DB8500_PRCMU) += db8500-prcmu.o
 obj-$(CONFIG_REGULATOR_TPS65910) += tps65910-regulator.o
 obj-$(CONFIG_REGULATOR_TPS62360) += tps62360-regulator.o
+obj-$(CONFIG_REGULATOR_TPS6238X0) += tps6238x0-regulator.o
 obj-$(CONFIG_REGULATOR_AAT2870) += aat2870-regulator.o
 obj-$(CONFIG_REGULATOR_FAN53555) += fan53555-regulator.o
 ccflags-$(CONFIG_REGULATOR_DEBUG) += -DDEBUG
diff --git a/drivers/regulator/tps6238x0-regulator.c b/drivers/regulator/tps6238x0-regulator.c
new file mode 100644 (file)
index 0000000..8802496
--- /dev/null
@@ -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");
diff --git a/include/linux/regulator/tps6238x0-regulator.h b/include/linux/regulator/tps6238x0-regulator.h
new file mode 100644 (file)
index 0000000..bc2b55b
--- /dev/null
@@ -0,0 +1,49 @@
+/*
+ * tps6238x0-regulator.h -- TI TPS623850/TPS623860/TPS623870
+ *
+ * Interface for regulator driver for TI TPS623850/TPS623860/TPS623870
+ * Processor core supply
+ *
+ * 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; 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef __LINUX_REGULATOR_TPS6238X0_H
+#define __LINUX_REGULATOR_TPS6238X0_H
+
+/*
+ * struct tps6238x0_regulator_platform_data - tps62360 regulator platform data.
+ *
+ * @init_data: The regulator init data.
+ * @en_discharge: Enable discharge the output capacitor via internal
+ *                register.
+ * @en_internal_pulldn: internal pull down enable or not.
+ * @vsel_gpio: Gpio number for vsel. It should be -1 if this is tied with
+ *              fixed logic.
+ * @vsel_def_state: Default state of vsel. 1 if it is high else 0.
+ */
+struct tps6238x0_regulator_platform_data {
+       struct regulator_init_data *init_data;
+       bool en_discharge;
+       bool en_internal_pulldn;
+       int vsel_gpio;
+       int vsel_def_state;
+};
+
+#endif /* __LINUX_REGULATOR_TPS6238X0_H */