regulator: Add support for RICOH PMIC RC5T583 regulator

The RC5T583 PMIC from RICOH consists of 4 DCDC and 10
LDOs. This driver supports the control of different
regulator output through regulator interface.
This driver depends on MFD driver of RC5T583 and uses
mfd rc5t583 apis to communicate to device for accessing
different device's registers.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 367 insertions, 0 deletions

diff --git a/drivers/regulator/rc5t583-regulator.c b/drivers/regulator/rc5t583-regulator.c
new file mode 100644
index 000000000000..37732f7c798d
--- /dev/null
+++ b/drivers/regulator/rc5t583-regulator.c
@@ -0,0 +1,367 @@
+/*
+ * Regulator driver for RICOH RC5T583 power management chip.
+ *
+ * Copyright (c) 2011-2012, NVIDIA CORPORATION.  All rights reserved.
+ * Author: Laxman dewangan <ldewangan@nvidia.com>
+ *
+ * based on code
+ *      Copyright (C) 2011 RICOH COMPANY,LTD
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/gpio.h>
+#include <linux/mfd/rc5t583.h>
+
+struct rc5t583_regulator_info {
+        int                     deepsleep_id;
+
+        /* Regulator register address.*/
+        uint8_t                 reg_en_reg;
+        uint8_t                 en_bit;
+        uint8_t                 reg_disc_reg;
+        uint8_t                 disc_bit;
+        uint8_t                 vout_reg;
+        uint8_t                 vout_mask;
+        uint8_t                 deepsleep_reg;
+
+        /* Chip constraints on regulator behavior */
+        int                     min_uV;
+        int                     max_uV;
+        int                     step_uV;
+        int                     nsteps;
+
+        /* Regulator specific turn-on delay  and voltage settling time*/
+        int                     enable_uv_per_us;
+        int                     change_uv_per_us;
+
+        /* Used by regulator core */
+        struct regulator_desc   desc;
+};
+
+struct rc5t583_regulator {
+        struct rc5t583_regulator_info *reg_info;
+
+        /* Devices */
+        struct device           *dev;
+        struct rc5t583          *mfd;
+        struct regulator_dev    *rdev;
+};
+
+static int rc5t583_reg_is_enabled(struct regulator_dev *rdev)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        struct rc5t583_regulator_info *ri = reg->reg_info;
+        uint8_t control;
+        int ret;
+
+        ret = rc5t583_read(reg->mfd->dev, ri->reg_en_reg, &control);
+        if (ret < 0) {
+                dev_err(&rdev->dev,
+                        "Error in reading the control register 0x%02x\n",
+                        ri->reg_en_reg);
+                return ret;
+        }
+        return !!(control & BIT(ri->en_bit));
+}
+
+static int rc5t583_reg_enable(struct regulator_dev *rdev)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        struct rc5t583_regulator_info *ri = reg->reg_info;
+        int ret;
+
+        ret = rc5t583_set_bits(reg->mfd->dev, ri->reg_en_reg,
+                                (1 << ri->en_bit));
+        if (ret < 0) {
+                dev_err(&rdev->dev,
+                        "Error in setting bit of STATE register 0x%02x\n",
+                        ri->reg_en_reg);
+                return ret;
+        }
+        return ret;
+}
+
+static int rc5t583_reg_disable(struct regulator_dev *rdev)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        struct rc5t583_regulator_info *ri = reg->reg_info;
+        int ret;
+
+        ret = rc5t583_clear_bits(reg->mfd->dev, ri->reg_en_reg,
+                                (1 << ri->en_bit));
+        if (ret < 0)
+                dev_err(&rdev->dev,
+                        "Error in clearing bit of STATE register 0x%02x\n",
+                        ri->reg_en_reg);
+
+        return ret;
+}
+
+static int rc5t583_list_voltage(struct regulator_dev *rdev, unsigned selector)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        struct rc5t583_regulator_info *ri = reg->reg_info;
+        return ri->min_uV + (ri->step_uV * selector);
+}
+
+static int rc5t583_set_voltage_sel(struct regulator_dev *rdev,
+                unsigned int selector)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        struct rc5t583_regulator_info *ri = reg->reg_info;
+        int ret;
+        if (selector > ri->nsteps) {
+                dev_err(&rdev->dev, "Invalid selector 0x%02x\n", selector);
+                return -EINVAL;
+        }
+
+        ret = rc5t583_update(reg->mfd->dev, ri->vout_reg,
+                                selector, ri->vout_mask);
+        if (ret < 0)
+                dev_err(&rdev->dev,
+                    "Error in update voltage register 0x%02x\n", ri->vout_reg);
+        return ret;
+}
+
+static int rc5t583_get_voltage_sel(struct regulator_dev *rdev)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        struct rc5t583_regulator_info *ri = reg->reg_info;
+        uint8_t vsel;
+        int ret;
+        ret = rc5t583_read(reg->mfd->dev, ri->vout_reg, &vsel);
+        if (ret < 0) {
+                dev_err(&rdev->dev,
+                    "Error in reading voltage register 0x%02x\n", ri->vout_reg);
+                return ret;
+        }
+        return vsel & ri->vout_mask;
+}
+
+static int rc5t583_regulator_enable_time(struct regulator_dev *rdev)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        int vsel = rc5t583_get_voltage_sel(rdev);
+        int curr_uV = rc5t583_list_voltage(rdev, vsel);
+        return DIV_ROUND_UP(curr_uV, reg->reg_info->enable_uv_per_us);
+}
+
+static int rc5t583_set_voltage_time_sel(struct regulator_dev *rdev,
+                unsigned int old_selector, unsigned int new_selector)
+{
+        struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
+        int old_uV, new_uV;
+        old_uV = rc5t583_list_voltage(rdev, old_selector);
+
+        if (old_uV < 0)
+                return old_uV;
+
+        new_uV = rc5t583_list_voltage(rdev, new_selector);
+        if (new_uV < 0)
+                return new_uV;
+
+        return DIV_ROUND_UP(abs(old_uV - new_uV),
+                                reg->reg_info->change_uv_per_us);
+}
+
+
+static struct regulator_ops rc5t583_ops = {
+        .is_enabled             = rc5t583_reg_is_enabled,
+        .enable                 = rc5t583_reg_enable,
+        .disable                = rc5t583_reg_disable,
+        .enable_time            = rc5t583_regulator_enable_time,
+        .get_voltage_sel        = rc5t583_get_voltage_sel,
+        .set_voltage_sel        = rc5t583_set_voltage_sel,
+        .list_voltage           = rc5t583_list_voltage,
+        .set_voltage_time_sel   = rc5t583_set_voltage_time_sel,
+};
+
+#define RC5T583_REG(_id, _en_reg, _en_bit, _disc_reg, _disc_bit, _vout_reg,  \
+                _vout_mask, _ds_reg, _min_mv, _max_mv, _step_uV, _nsteps,    \
+                _enable_mv)                                     \
+{                                                               \
+        .reg_en_reg     = RC5T583_REG_##_en_reg,                \
+        .en_bit         = _en_bit,                              \
+        .reg_disc_reg   = RC5T583_REG_##_disc_reg,              \
+        .disc_bit       = _disc_bit,                            \
+        .vout_reg       = RC5T583_REG_##_vout_reg,              \
+        .vout_mask      = _vout_mask,                           \
+        .deepsleep_reg  = RC5T583_REG_##_ds_reg,                \
+        .min_uV         = _min_mv * 1000,                       \
+        .max_uV         = _max_mv * 1000,                       \
+        .step_uV        = _step_uV,                             \
+        .nsteps         = _nsteps,                              \
+        .enable_uv_per_us = _enable_mv * 1000,                  \
+        .change_uv_per_us = 40 * 1000,                          \
+        .deepsleep_id   = RC5T583_DS_##_id,                     \
+        .desc = {                                               \
+                .name = "rc5t583-regulator-"#_id,               \
+                .id = RC5T583_REGULATOR_##_id,                  \
+                .n_voltages = _nsteps,                          \
+                .ops = &rc5t583_ops,                            \
+                .type = REGULATOR_VOLTAGE,                      \
+                .owner = THIS_MODULE,                           \
+        },                                                      \
+}
+
+static struct rc5t583_regulator_info rc5t583_reg_info[RC5T583_REGULATOR_MAX] = {
+        RC5T583_REG(DC0, DC0CTL, 0, DC0CTL, 1, DC0DAC, 0x7F, DC0DAC_DS,
+                        700, 1500, 12500, 0x41, 4),
+        RC5T583_REG(DC1, DC1CTL, 0, DC1CTL, 1, DC1DAC, 0x7F, DC1DAC_DS,
+                        700, 1500, 12500, 0x41,  14),
+        RC5T583_REG(DC2, DC2CTL, 0, DC2CTL, 1, DC2DAC, 0x7F, DC2DAC_DS,
+                        900, 2400, 12500, 0x79,  14),
+        RC5T583_REG(DC3, DC3CTL, 0, DC3CTL, 1, DC3DAC, 0x7F, DC3DAC_DS,
+                        900, 2400, 12500, 0x79,  14),
+        RC5T583_REG(LDO0, LDOEN2, 0, LDODIS2, 0, LDO0DAC, 0x7F, LDO0DAC_DS,
+                        900, 3400, 25000, 0x65,  160),
+        RC5T583_REG(LDO1, LDOEN2, 1, LDODIS2, 1, LDO1DAC, 0x7F, LDO1DAC_DS,
+                        900, 3400, 25000, 0x65,  160),
+        RC5T583_REG(LDO2, LDOEN2, 2, LDODIS2, 2, LDO2DAC, 0x7F, LDO2DAC_DS,
+                        900, 3400, 25000, 0x65,  160),
+        RC5T583_REG(LDO3, LDOEN2, 3, LDODIS2, 3, LDO3DAC, 0x7F, LDO3DAC_DS,
+                        900, 3400, 25000, 0x65,  160),
+        RC5T583_REG(LDO4, LDOEN2, 4, LDODIS2, 4, LDO4DAC, 0x3F, LDO4DAC_DS,
+                        750, 1500, 12500, 0x3D,  133),
+        RC5T583_REG(LDO5, LDOEN2, 5, LDODIS2, 5, LDO5DAC, 0x7F, LDO5DAC_DS,
+                        900, 3400, 25000, 0x65,  267),
+        RC5T583_REG(LDO6, LDOEN2, 6, LDODIS2, 6, LDO6DAC, 0x7F, LDO6DAC_DS,
+                        900, 3400, 25000, 0x65,  133),
+        RC5T583_REG(LDO7, LDOEN2, 7, LDODIS2, 7, LDO7DAC, 0x7F, LDO7DAC_DS,
+                        900, 3400, 25000, 0x65,  233),
+        RC5T583_REG(LDO8, LDOEN1, 0, LDODIS1, 0, LDO8DAC, 0x7F, LDO8DAC_DS,
+                        900, 3400, 25000, 0x65,  233),
+        RC5T583_REG(LDO9, LDOEN1, 1, LDODIS1, 1, LDO9DAC, 0x7F, LDO9DAC_DS,
+                        900, 3400, 25000, 0x65,  133),
+};
+
+static int __devinit rc5t583_regulator_probe(struct platform_device *pdev)
+{
+        struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
+        struct rc5t583_platform_data *pdata = dev_get_platdata(rc5t583->dev);
+        struct regulator_init_data *reg_data;
+        struct rc5t583_regulator *reg = NULL;
+        struct rc5t583_regulator *regs;
+        struct regulator_dev *rdev;
+        struct rc5t583_regulator_info *ri;
+        int ret;
+        int id;
+
+        if (!pdata) {
+                dev_err(&pdev->dev, "No platform data, exiting...\n");
+                return -ENODEV;
+        }
+
+        regs = devm_kzalloc(&pdev->dev, RC5T583_REGULATOR_MAX *
+                        sizeof(struct rc5t583_regulator), GFP_KERNEL);
+        if (!regs) {
+                dev_err(&pdev->dev, "Memory allocation failed exiting..\n");
+                return -ENOMEM;
+        }
+
+
+        for (id = 0; id < RC5T583_REGULATOR_MAX; ++id) {
+                reg_data = pdata->reg_init_data[id];
+
+                /* No need to register if there is no regulator data */
+                if (!reg_data)
+                        continue;
+
+                reg = &regs[id];
+                ri = &rc5t583_reg_info[id];
+                reg->reg_info = ri;
+                reg->mfd = rc5t583;
+                reg->dev = &pdev->dev;
+
+                if (ri->deepsleep_id == RC5T583_DS_NONE)
+                        goto skip_ext_pwr_config;
+
+                ret = rc5t583_ext_power_req_config(rc5t583->dev,
+                                ri->deepsleep_id,
+                                pdata->regulator_ext_pwr_control[id],
+                                pdata->regulator_deepsleep_slot[id]);
+                /*
+                 * Configuring external control is not a major issue,
+                 * just give warning.
+                 */
+                if (ret < 0)
+                        dev_warn(&pdev->dev,
+                                "Failed to configure ext control %d\n", id);
+
+skip_ext_pwr_config:
+                rdev = regulator_register(&ri->desc, &pdev->dev,
+                                        reg_data, reg, NULL);
+                if (IS_ERR_OR_NULL(rdev)) {
+                        dev_err(&pdev->dev, "Failed to register regulator %s\n",
+                                                ri->desc.name);
+                        ret = PTR_ERR(rdev);
+                        goto clean_exit;
+                }
+                reg->rdev = rdev;
+        }
+        platform_set_drvdata(pdev, regs);
+        return 0;
+
+clean_exit:
+        while (--id > 0)
+                regulator_unregister(regs[id].rdev);
+
+        return ret;
+}
+
+static int __devexit rc5t583_regulator_remove(struct platform_device *pdev)
+{
+        struct rc5t583_regulator *regs = platform_get_drvdata(pdev);
+        int id;
+
+        for (id = 0; id < RC5T583_REGULATOR_MAX; ++id)
+                regulator_unregister(regs[id].rdev);
+        return 0;
+}
+
+static struct platform_driver rc5t583_regulator_driver = {
+        .driver = {
+                .name   = "rc5t583-regulator",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = rc5t583_regulator_probe,
+        .remove         = __devexit_p(rc5t583_regulator_remove),
+};
+
+static int __init rc5t583_regulator_init(void)
+{
+        return platform_driver_register(&rc5t583_regulator_driver);
+}
+subsys_initcall(rc5t583_regulator_init);
+
+static void __exit rc5t583_regulator_exit(void)
+{
+        platform_driver_unregister(&rc5t583_regulator_driver);
+}
+module_exit(rc5t583_regulator_exit);
+
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_DESCRIPTION("RC5T583 regulator driver");
+MODULE_ALIAS("platform:rc5t583-regulator");
+MODULE_LICENSE("GPL V2");