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-rw-r--r--drivers/regulator/max1586.c316
1 files changed, 316 insertions, 0 deletions
diff --git a/drivers/regulator/max1586.c b/drivers/regulator/max1586.c
new file mode 100644
index 000000000..d4958394e
--- /dev/null
+++ b/drivers/regulator/max1586.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * max1586.c -- Voltage and current regulation for the Maxim 1586
+ *
+ * Copyright (C) 2008 Robert Jarzmik
+ */
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/slab.h>
+#include <linux/regulator/max1586.h>
+#include <linux/of_device.h>
+#include <linux/regulator/of_regulator.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;
+
+ unsigned int v3_curr_sel;
+ unsigned int v6_curr_sel;
+};
+
+/*
+ * 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 const unsigned int v6_voltages_uv[] = { 1, 1800000, 2500000, 3000000 };
+
+/*
+ * 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_get_voltage_sel(struct regulator_dev *rdev)
+{
+ struct max1586_data *max1586 = rdev_get_drvdata(rdev);
+
+ return max1586->v3_curr_sel;
+}
+
+static int max1586_v3_set_voltage_sel(struct regulator_dev *rdev,
+ unsigned selector)
+{
+ struct max1586_data *max1586 = rdev_get_drvdata(rdev);
+ struct i2c_client *client = max1586->client;
+ int ret;
+ u8 v3_prog;
+
+ dev_dbg(&client->dev, "changing voltage v3 to %dmv\n",
+ regulator_list_voltage_linear(rdev, selector) / 1000);
+
+ v3_prog = I2C_V3_SELECT | (u8) selector;
+ ret = i2c_smbus_write_byte(client, v3_prog);
+ if (ret)
+ return ret;
+
+ max1586->v3_curr_sel = selector;
+
+ return 0;
+}
+
+static int max1586_v6_get_voltage_sel(struct regulator_dev *rdev)
+{
+ struct max1586_data *max1586 = rdev_get_drvdata(rdev);
+
+ return max1586->v6_curr_sel;
+}
+
+static int max1586_v6_set_voltage_sel(struct regulator_dev *rdev,
+ unsigned int selector)
+{
+ struct max1586_data *max1586 = rdev_get_drvdata(rdev);
+ struct i2c_client *client = max1586->client;
+ u8 v6_prog;
+ int ret;
+
+ dev_dbg(&client->dev, "changing voltage v6 to %dmv\n",
+ rdev->desc->volt_table[selector] / 1000);
+
+ v6_prog = I2C_V6_SELECT | (u8) selector;
+ ret = i2c_smbus_write_byte(client, v6_prog);
+ if (ret)
+ return ret;
+
+ max1586->v6_curr_sel = selector;
+
+ return 0;
+}
+
+/*
+ * The Maxim 1586 controls V3 and V6 voltages, but offers no way of reading back
+ * the set up value.
+ */
+static const struct regulator_ops max1586_v3_ops = {
+ .get_voltage_sel = max1586_v3_get_voltage_sel,
+ .set_voltage_sel = max1586_v3_set_voltage_sel,
+ .list_voltage = regulator_list_voltage_linear,
+ .map_voltage = regulator_map_voltage_linear,
+};
+
+static const struct regulator_ops max1586_v6_ops = {
+ .get_voltage_sel = max1586_v6_get_voltage_sel,
+ .set_voltage_sel = max1586_v6_set_voltage_sel,
+ .list_voltage = regulator_list_voltage_table,
+};
+
+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,
+ .volt_table = v6_voltages_uv,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int of_get_max1586_platform_data(struct device *dev,
+ struct max1586_platform_data *pdata)
+{
+ struct max1586_subdev_data *sub;
+ struct of_regulator_match rmatch[ARRAY_SIZE(max1586_reg)] = { };
+ struct device_node *np = dev->of_node;
+ int i, matched;
+
+ if (of_property_read_u32(np, "v3-gain",
+ &pdata->v3_gain) < 0) {
+ dev_err(dev, "%pOF has no 'v3-gain' property\n", np);
+ return -EINVAL;
+ }
+
+ np = of_get_child_by_name(np, "regulators");
+ if (!np) {
+ dev_err(dev, "missing 'regulators' subnode in DT\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(rmatch); i++)
+ rmatch[i].name = max1586_reg[i].name;
+
+ matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch));
+ of_node_put(np);
+ /*
+ * If matched is 0, ie. neither Output_V3 nor Output_V6 have been found,
+ * return 0, which signals the normal situation where no subregulator is
+ * available. This is normal because the max1586 doesn't provide any
+ * readback support, so the subregulators can't report any status
+ * anyway. If matched < 0, return the error.
+ */
+ if (matched <= 0)
+ return matched;
+
+ pdata->subdevs = devm_kcalloc(dev,
+ matched,
+ sizeof(struct max1586_subdev_data),
+ GFP_KERNEL);
+ if (!pdata->subdevs)
+ return -ENOMEM;
+
+ pdata->num_subdevs = matched;
+ sub = pdata->subdevs;
+
+ for (i = 0; i < matched; i++) {
+ sub->id = i;
+ sub->name = rmatch[i].of_node->name;
+ sub->platform_data = rmatch[i].init_data;
+ sub++;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id __maybe_unused max1586_of_match[] = {
+ { .compatible = "maxim,max1586", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, max1586_of_match);
+
+static int max1586_pmic_probe(struct i2c_client *client,
+ const struct i2c_device_id *i2c_id)
+{
+ struct max1586_platform_data *pdata, pdata_of;
+ struct regulator_config config = { };
+ struct max1586_data *max1586;
+ int i, id, ret;
+ const struct of_device_id *match;
+
+ pdata = dev_get_platdata(&client->dev);
+ if (client->dev.of_node && !pdata) {
+ match = of_match_device(of_match_ptr(max1586_of_match),
+ &client->dev);
+ if (!match) {
+ dev_err(&client->dev, "Error: No device match found\n");
+ return -ENODEV;
+ }
+ ret = of_get_max1586_platform_data(&client->dev, &pdata_of);
+ if (ret < 0)
+ return ret;
+ pdata = &pdata_of;
+ }
+
+ max1586 = devm_kzalloc(&client->dev, sizeof(struct max1586_data),
+ GFP_KERNEL);
+ if (!max1586)
+ return -ENOMEM;
+
+ max1586->client = client;
+
+ if (!pdata->v3_gain)
+ return -EINVAL;
+
+ max1586->min_uV = MAX1586_V3_MIN_UV / 1000 * pdata->v3_gain / 1000;
+ max1586->max_uV = MAX1586_V3_MAX_UV / 1000 * pdata->v3_gain / 1000;
+
+ /* Set curr_sel to default voltage on power-up */
+ max1586->v3_curr_sel = 24; /* 1.3V */
+ max1586->v6_curr_sel = 0;
+
+ for (i = 0; i < pdata->num_subdevs && i <= MAX1586_V6; i++) {
+ struct regulator_dev *rdev;
+
+ 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);
+ return -EINVAL;
+ }
+
+ if (id == MAX1586_V3) {
+ max1586_reg[id].min_uV = max1586->min_uV;
+ max1586_reg[id].uV_step =
+ (max1586->max_uV - max1586->min_uV) /
+ MAX1586_V3_MAX_VSEL;
+ }
+
+ config.dev = &client->dev;
+ config.init_data = pdata->subdevs[i].platform_data;
+ config.driver_data = max1586;
+
+ rdev = devm_regulator_register(&client->dev,
+ &max1586_reg[id], &config);
+ if (IS_ERR(rdev)) {
+ dev_err(&client->dev, "failed to register %s\n",
+ max1586_reg[id].name);
+ return PTR_ERR(rdev);
+ }
+ }
+
+ i2c_set_clientdata(client, max1586);
+ dev_info(&client->dev, "Maxim 1586 regulator driver loaded\n");
+ 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,
+ .driver = {
+ .name = "max1586",
+ .of_match_table = of_match_ptr(max1586_of_match),
+ },
+ .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");