--- /dev/null
+/*
+ * 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/regulator/max8649.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 i2c_client *i2c;
+ struct device *dev;
+ struct mutex io_lock;
+
+ 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 max8649_read_device(struct i2c_client *i2c,
+ int reg, int bytes, void *dest)
+{
+ unsigned char data;
+ int ret;
+
+ data = (unsigned char)reg;
+ ret = i2c_master_send(i2c, &data, 1);
+ if (ret < 0)
+ return ret;
+ ret = i2c_master_recv(i2c, dest, bytes);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static inline int max8649_write_device(struct i2c_client *i2c,
+ int reg, int bytes, void *src)
+{
+ unsigned char buf[bytes + 1];
+ int ret;
+
+ buf[0] = (unsigned char)reg;
+ memcpy(&buf[1], src, bytes);
+
+ ret = i2c_master_send(i2c, buf, bytes + 1);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static int max8649_reg_read(struct i2c_client *i2c, int reg)
+{
+ struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+ unsigned char data;
+ int ret;
+
+ mutex_lock(&info->io_lock);
+ ret = max8649_read_device(i2c, reg, 1, &data);
+ mutex_unlock(&info->io_lock);
+
+ if (ret < 0)
+ return ret;
+ return (int)data;
+}
+
+static int max8649_set_bits(struct i2c_client *i2c, int reg,
+ unsigned char mask, unsigned char data)
+{
+ struct max8649_regulator_info *info = i2c_get_clientdata(i2c);
+ unsigned char value;
+ int ret;
+
+ mutex_lock(&info->io_lock);
+ ret = max8649_read_device(i2c, reg, 1, &value);
+ if (ret < 0)
+ goto out;
+ value &= ~mask;
+ value |= data;
+ ret = max8649_write_device(i2c, reg, 1, &value);
+out:
+ mutex_unlock(&info->io_lock);
+ return ret;
+}
+
+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 char data;
+ int ret;
+
+ ret = max8649_reg_read(info->i2c, info->vol_reg);
+ if (ret < 0)
+ return ret;
+ data = (unsigned char)ret & MAX8649_VOL_MASK;
+ return max8649_list_voltage(rdev, data);
+}
+
+static int max8649_set_voltage(struct regulator_dev *rdev,
+ int min_uV, int max_uV)
+{
+ 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 = (min_uV - MAX8649_DCDC_VMIN + MAX8649_DCDC_STEP - 1)
+ / MAX8649_DCDC_STEP;
+ mask = MAX8649_VOL_MASK;
+
+ return max8649_set_bits(info->i2c, 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 max8649_set_bits(info->i2c, 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 max8649_set_bits(info->i2c, 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);
+ int ret;
+
+ ret = max8649_reg_read(info->i2c, MAX8649_CONTROL);
+ if (ret < 0)
+ return ret;
+ return !((unsigned char)ret & 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;
+
+ /* get voltage */
+ ret = max8649_reg_read(info->i2c, info->vol_reg);
+ if (ret < 0)
+ return ret;
+ ret &= MAX8649_VOL_MASK;
+ voltage = max8649_list_voltage(rdev, (unsigned char)ret); /* uV */
+
+ /* get rate */
+ ret = max8649_reg_read(info->i2c, MAX8649_RAMP);
+ if (ret < 0)
+ return ret;
+ ret = (ret & MAX8649_RAMP_MASK) >> 5;
+ rate = (32 * 1000) >> ret; /* uV/uS */
+
+ return (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:
+ max8649_set_bits(info->i2c, info->vol_reg, MAX8649_FORCE_PWM,
+ MAX8649_FORCE_PWM);
+ break;
+ case REGULATOR_MODE_NORMAL:
+ max8649_set_bits(info->i2c, 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);
+ int ret;
+
+ ret = max8649_reg_read(info->i2c, info->vol_reg);
+ if (ret & 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 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 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->i2c = client;
+ info->dev = &client->dev;
+ mutex_init(&info->io_lock);
+ 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 = max8649_reg_read(info->i2c, MAX8649_CHIP_ID1);
+ 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", ret);
+
+ /* enable VID0 & VID1 */
+ max8649_set_bits(info->i2c, MAX8649_CONTROL, MAX8649_VID_MASK, 0);
+
+ /* enable/disable external clock synchronization */
+ info->extclk = pdata->extclk;
+ data = (info->extclk) ? MAX8649_SYNC_EXTCLK : 0;
+ max8649_set_bits(info->i2c, info->vol_reg, MAX8649_SYNC_EXTCLK, data);
+ if (info->extclk) {
+ /* set external clock frequency */
+ info->extclk_freq = pdata->extclk_freq;
+ max8649_set_bits(info->i2c, MAX8649_SYNC, MAX8649_EXT_MASK,
+ info->extclk_freq);
+ }
+
+ if (pdata->ramp_timing) {
+ info->ramp_timing = pdata->ramp_timing;
+ max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_MASK,
+ info->ramp_timing << 5);
+ }
+
+ info->ramp_down = pdata->ramp_down;
+ if (info->ramp_down) {
+ max8649_set_bits(info->i2c, MAX8649_RAMP, MAX8649_RAMP_DOWN,
+ MAX8649_RAMP_DOWN);
+ }
+
+ info->regulator = regulator_register(&dcdc_desc, &client->dev,
+ pdata->regulator, info);
+ 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:
+ 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);
+ kfree(info);
+ }
+ i2c_set_clientdata(client, NULL);
+
+ 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");
+
projects / platform / kernel / kernel-mfld-blackbay.git / commitdiff