1 files changed, 282 insertions, 0 deletions

diff --git a/drivers/regulator/max1586.c b/drivers/regulator/max1586.c
new file mode 100644
index 000000000000..2c082d3ef484
--- /dev/null
+++ b/drivers/regulator/max1586.c
@@ -0,0 +1,282 @@
+/*
+ * max1586.c  --  Voltage and current regulation for the Maxim 1586
+ *
+ * Copyright (C) 2008 Robert Jarzmik
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#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/max1586.h>
+
+#define MAX1586_V3_MAX_VSEL 31
+#define MAX1586_V6_MAX_VSEL 3
+
+#define MAX1586_V3_MIN_UV   700000
+#define MAX1586_V3_MAX_UV  1475000
+
+#define MAX1586_V6_MIN_UV        0
+#define MAX1586_V6_MAX_UV  3000000
+
+#define I2C_V3_SELECT (0 << 5)
+#define I2C_V6_SELECT (1 << 5)
+
+struct max1586_data {
+        struct i2c_client *client;
+
+        /* min/max V3 voltage */
+        unsigned int min_uV;
+        unsigned int max_uV;
+
+        struct regulator_dev *rdev[0];
+};
+
+/*
+ * V3 voltage
+ * On I2C bus, sending a "x" byte to the max1586 means :
+ *   set V3 to 0.700V + (x & 0x1f) * 0.025V
+ * This voltage can be increased by external resistors
+ * R24 and R25=100kOhm as described in the data sheet.
+ * The gain is approximately: 1 + R24/R25 + R24/185.5kOhm
+ */
+static int max1586_v3_calc_voltage(struct max1586_data *max1586,
+        unsigned selector)
+{
+        unsigned range_uV = max1586->max_uV - max1586->min_uV;
+
+        return max1586->min_uV + (selector * range_uV / MAX1586_V3_MAX_VSEL);
+}
+
+static int max1586_v3_set(struct regulator_dev *rdev, int min_uV, int max_uV)
+{
+        struct max1586_data *max1586 = rdev_get_drvdata(rdev);
+        struct i2c_client *client = max1586->client;
+        unsigned range_uV = max1586->max_uV - max1586->min_uV;
+        unsigned selector;
+        u8 v3_prog;
+
+        if (min_uV > max1586->max_uV || max_uV < max1586->min_uV)
+                return -EINVAL;
+        if (min_uV < max1586->min_uV)
+                min_uV = max1586->min_uV;
+
+        selector = ((min_uV - max1586->min_uV) * MAX1586_V3_MAX_VSEL +
+                        range_uV - 1) / range_uV;
+        if (max1586_v3_calc_voltage(max1586, selector) > max_uV)
+                return -EINVAL;
+
+        dev_dbg(&client->dev, "changing voltage v3 to %dmv\n",
+                max1586_v3_calc_voltage(max1586, selector) / 1000);
+
+        v3_prog = I2C_V3_SELECT | (u8) selector;
+        return i2c_smbus_write_byte(client, v3_prog);
+}
+
+static int max1586_v3_list(struct regulator_dev *rdev, unsigned selector)
+{
+        struct max1586_data *max1586 = rdev_get_drvdata(rdev);
+
+        if (selector > MAX1586_V3_MAX_VSEL)
+                return -EINVAL;
+        return max1586_v3_calc_voltage(max1586, selector);
+}
+
+/*
+ * V6 voltage
+ * On I2C bus, sending a "x" byte to the max1586 means :
+ *   set V6 to either 0V, 1.8V, 2.5V, 3V depending on (x & 0x3)
+ * As regulator framework doesn't accept voltages to be 0V, we use 1uV.
+ */
+static int max1586_v6_calc_voltage(unsigned selector)
+{
+        static int voltages_uv[] = { 1, 1800000, 2500000, 3000000 };
+
+        return voltages_uv[selector];
+}
+
+static int max1586_v6_set(struct regulator_dev *rdev, int min_uV, int max_uV)
+{
+        struct i2c_client *client = rdev_get_drvdata(rdev);
+        unsigned selector;
+        u8 v6_prog;
+
+        if (min_uV < MAX1586_V6_MIN_UV || min_uV > MAX1586_V6_MAX_UV)
+                return -EINVAL;
+        if (max_uV < MAX1586_V6_MIN_UV || max_uV > MAX1586_V6_MAX_UV)
+                return -EINVAL;
+
+        if (min_uV >= 3000000)
+                selector = 3;
+        if (min_uV < 3000000)
+                selector = 2;
+        if (min_uV < 2500000)
+                selector = 1;
+        if (min_uV < 1800000)
+                selector = 0;
+
+        if (max1586_v6_calc_voltage(selector) > max_uV)
+                return -EINVAL;
+
+        dev_dbg(&client->dev, "changing voltage v6 to %dmv\n",
+                max1586_v6_calc_voltage(selector) / 1000);
+
+        v6_prog = I2C_V6_SELECT | (u8) selector;
+        return i2c_smbus_write_byte(client, v6_prog);
+}
+
+static int max1586_v6_list(struct regulator_dev *rdev, unsigned selector)
+{
+        if (selector > MAX1586_V6_MAX_VSEL)
+                return -EINVAL;
+        return max1586_v6_calc_voltage(selector);
+}
+
+/*
+ * The Maxim 1586 controls V3 and V6 voltages, but offers no way of reading back
+ * the set up value.
+ */
+static struct regulator_ops max1586_v3_ops = {
+        .set_voltage = max1586_v3_set,
+        .list_voltage = max1586_v3_list,
+};
+
+static struct regulator_ops max1586_v6_ops = {
+        .set_voltage = max1586_v6_set,
+        .list_voltage = max1586_v6_list,
+};
+
+static struct regulator_desc max1586_reg[] = {
+        {
+                .name = "Output_V3",
+                .id = MAX1586_V3,
+                .ops = &max1586_v3_ops,
+                .type = REGULATOR_VOLTAGE,
+                .n_voltages = MAX1586_V3_MAX_VSEL + 1,
+                .owner = THIS_MODULE,
+        },
+        {
+                .name = "Output_V6",
+                .id = MAX1586_V6,
+                .ops = &max1586_v6_ops,
+                .type = REGULATOR_VOLTAGE,
+                .n_voltages = MAX1586_V6_MAX_VSEL + 1,
+                .owner = THIS_MODULE,
+        },
+};
+
+static int max1586_pmic_probe(struct i2c_client *client,
+                              const struct i2c_device_id *i2c_id)
+{
+        struct regulator_dev **rdev;
+        struct max1586_platform_data *pdata = client->dev.platform_data;
+        struct max1586_data *max1586;
+        int i, id, ret = -ENOMEM;
+
+        max1586 = kzalloc(sizeof(struct max1586_data) +
+                        sizeof(struct regulator_dev *) * (MAX1586_V6 + 1),
+                        GFP_KERNEL);
+        if (!max1586)
+                goto out;
+
+        max1586->client = client;
+
+        if (!pdata->v3_gain) {
+                ret = -EINVAL;
+                goto out_unmap;
+        }
+        max1586->min_uV = MAX1586_V3_MIN_UV / 1000 * pdata->v3_gain / 1000;
+        max1586->max_uV = MAX1586_V3_MAX_UV / 1000 * pdata->v3_gain / 1000;
+
+        rdev = max1586->rdev;
+        for (i = 0; i < pdata->num_subdevs && i <= MAX1586_V6; i++) {
+                id = pdata->subdevs[i].id;
+                if (!pdata->subdevs[i].platform_data)
+                        continue;
+                if (id < MAX1586_V3 || id > MAX1586_V6) {
+                        dev_err(&client->dev, "invalid regulator id %d\n", id);
+                        goto err;
+                }
+                rdev[i] = regulator_register(&max1586_reg[id], &client->dev,
+                                             pdata->subdevs[i].platform_data,
+                                             max1586);
+                if (IS_ERR(rdev[i])) {
+                        ret = PTR_ERR(rdev[i]);
+                        dev_err(&client->dev, "failed to register %s\n",
+                                max1586_reg[id].name);
+                        goto err;
+                }
+        }
+
+        i2c_set_clientdata(client, rdev);
+        dev_info(&client->dev, "Maxim 1586 regulator driver loaded\n");
+        return 0;
+
+err:
+        while (--i >= 0)
+                regulator_unregister(rdev[i]);
+out_unmap:
+        kfree(max1586);
+out:
+        return ret;
+}
+
+static int max1586_pmic_remove(struct i2c_client *client)
+{
+        struct regulator_dev **rdev = i2c_get_clientdata(client);
+        int i;
+
+        for (i = 0; i <= MAX1586_V6; i++)
+                if (rdev[i])
+                        regulator_unregister(rdev[i]);
+        kfree(rdev);
+        i2c_set_clientdata(client, NULL);
+
+        return 0;
+}
+
+static const struct i2c_device_id max1586_id[] = {
+        { "max1586", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, max1586_id);
+
+static struct i2c_driver max1586_pmic_driver = {
+        .probe = max1586_pmic_probe,
+        .remove = max1586_pmic_remove,
+        .driver         = {
+                .name   = "max1586",
+        },
+        .id_table       = max1586_id,
+};
+
+static int __init max1586_pmic_init(void)
+{
+        return i2c_add_driver(&max1586_pmic_driver);
+}
+subsys_initcall(max1586_pmic_init);
+
+static void __exit max1586_pmic_exit(void)
+{
+        i2c_del_driver(&max1586_pmic_driver);
+}
+module_exit(max1586_pmic_exit);
+
+/* Module information */
+MODULE_DESCRIPTION("MAXIM 1586 voltage regulator driver");
+MODULE_AUTHOR("Robert Jarzmik");
+MODULE_LICENSE("GPL");