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path: root/drivers/regulator/max77686-regulator.c
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Diffstat (limited to 'drivers/regulator/max77686-regulator.c')
-rw-r--r--drivers/regulator/max77686-regulator.c570
1 files changed, 570 insertions, 0 deletions
diff --git a/drivers/regulator/max77686-regulator.c b/drivers/regulator/max77686-regulator.c
new file mode 100644
index 000000000..17ccf365a
--- /dev/null
+++ b/drivers/regulator/max77686-regulator.c
@@ -0,0 +1,570 @@
+/*
+ * max77686.c - Regulator driver for the Maxim 77686
+ *
+ * Copyright (C) 2012 Samsung Electronics
+ * Chiwoong Byun <woong.byun@samsung.com>
+ * Jonghwa Lee <jonghwa3.lee@samsung.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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * This driver is based on max8997.c
+ */
+
+#include <linux/kernel.h>
+#include <linux/bug.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/mfd/max77686.h>
+#include <linux/mfd/max77686-private.h>
+
+#define MAX77686_LDO_MINUV 800000
+#define MAX77686_LDO_UVSTEP 50000
+#define MAX77686_LDO_LOW_MINUV 800000
+#define MAX77686_LDO_LOW_UVSTEP 25000
+#define MAX77686_BUCK_MINUV 750000
+#define MAX77686_BUCK_UVSTEP 50000
+#define MAX77686_RAMP_DELAY 100000 /* uV/us */
+#define MAX77686_DVS_RAMP_DELAY 27500 /* uV/us */
+#define MAX77686_DVS_MINUV 600000
+#define MAX77686_DVS_UVSTEP 12500
+
+/*
+ * Value for configuring buck[89] and LDO{20,21,22} as GPIO control.
+ * It is the same as 'off' for other regulators.
+ */
+#define MAX77686_GPIO_CONTROL 0x0
+/*
+ * Values used for configuring LDOs and bucks.
+ * Forcing low power mode: LDO1, 3-5, 9, 13, 17-26
+ */
+#define MAX77686_LDO_LOWPOWER 0x1
+/*
+ * On/off controlled by PWRREQ:
+ * - LDO2, 6-8, 10-12, 14-16
+ * - buck[1234]
+ */
+#define MAX77686_OFF_PWRREQ 0x1
+/* Low power mode controlled by PWRREQ: All LDOs */
+#define MAX77686_LDO_LOWPOWER_PWRREQ 0x2
+/* Forcing low power mode: buck[234] */
+#define MAX77686_BUCK_LOWPOWER 0x2
+#define MAX77686_NORMAL 0x3
+
+#define MAX77686_OPMODE_SHIFT 6
+#define MAX77686_OPMODE_BUCK234_SHIFT 4
+#define MAX77686_OPMODE_MASK 0x3
+
+#define MAX77686_VSEL_MASK 0x3F
+#define MAX77686_DVS_VSEL_MASK 0xFF
+
+#define MAX77686_RAMP_RATE_MASK 0xC0
+
+#define MAX77686_REGULATORS MAX77686_REG_MAX
+#define MAX77686_LDOS 26
+
+enum max77686_ramp_rate {
+ RAMP_RATE_13P75MV,
+ RAMP_RATE_27P5MV,
+ RAMP_RATE_55MV,
+ RAMP_RATE_NO_CTRL, /* 100mV/us */
+};
+
+struct max77686_data {
+ DECLARE_BITMAP(gpio_enabled, MAX77686_REGULATORS);
+
+ /* Array indexed by regulator id */
+ unsigned int opmode[MAX77686_REGULATORS];
+};
+
+static unsigned int max77686_get_opmode_shift(int id)
+{
+ switch (id) {
+ case MAX77686_BUCK1:
+ case MAX77686_BUCK5 ... MAX77686_BUCK9:
+ return 0;
+ case MAX77686_BUCK2 ... MAX77686_BUCK4:
+ return MAX77686_OPMODE_BUCK234_SHIFT;
+ default:
+ /* all LDOs */
+ return MAX77686_OPMODE_SHIFT;
+ }
+}
+
+/*
+ * When regulator is configured for GPIO control then it
+ * replaces "normal" mode. Any change from low power mode to normal
+ * should actually change to GPIO control.
+ * Map normal mode to proper value for such regulators.
+ */
+static unsigned int max77686_map_normal_mode(struct max77686_data *max77686,
+ int id)
+{
+ switch (id) {
+ case MAX77686_BUCK8:
+ case MAX77686_BUCK9:
+ case MAX77686_LDO20 ... MAX77686_LDO22:
+ if (test_bit(id, max77686->gpio_enabled))
+ return MAX77686_GPIO_CONTROL;
+ }
+
+ return MAX77686_NORMAL;
+}
+
+/* Some BUCKs and LDOs supports Normal[ON/OFF] mode during suspend */
+static int max77686_set_suspend_disable(struct regulator_dev *rdev)
+{
+ unsigned int val, shift;
+ struct max77686_data *max77686 = rdev_get_drvdata(rdev);
+ int ret, id = rdev_get_id(rdev);
+
+ shift = max77686_get_opmode_shift(id);
+ val = MAX77686_OFF_PWRREQ;
+
+ ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ rdev->desc->enable_mask, val << shift);
+ if (ret)
+ return ret;
+
+ max77686->opmode[id] = val;
+ return 0;
+}
+
+/* Some LDOs supports [LPM/Normal]ON mode during suspend state */
+static int max77686_set_suspend_mode(struct regulator_dev *rdev,
+ unsigned int mode)
+{
+ struct max77686_data *max77686 = rdev_get_drvdata(rdev);
+ unsigned int val;
+ int ret, id = rdev_get_id(rdev);
+
+ /* BUCK[5-9] doesn't support this feature */
+ if (id >= MAX77686_BUCK5)
+ return 0;
+
+ switch (mode) {
+ case REGULATOR_MODE_IDLE: /* ON in LP Mode */
+ val = MAX77686_LDO_LOWPOWER_PWRREQ;
+ break;
+ case REGULATOR_MODE_NORMAL: /* ON in Normal Mode */
+ val = max77686_map_normal_mode(max77686, id);
+ break;
+ default:
+ pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
+ rdev->desc->name, mode);
+ return -EINVAL;
+ }
+
+ ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ rdev->desc->enable_mask,
+ val << MAX77686_OPMODE_SHIFT);
+ if (ret)
+ return ret;
+
+ max77686->opmode[id] = val;
+ return 0;
+}
+
+/* Some LDOs supports LPM-ON/OFF/Normal-ON mode during suspend state */
+static int max77686_ldo_set_suspend_mode(struct regulator_dev *rdev,
+ unsigned int mode)
+{
+ unsigned int val;
+ struct max77686_data *max77686 = rdev_get_drvdata(rdev);
+ int ret, id = rdev_get_id(rdev);
+
+ switch (mode) {
+ case REGULATOR_MODE_STANDBY: /* switch off */
+ val = MAX77686_OFF_PWRREQ;
+ break;
+ case REGULATOR_MODE_IDLE: /* ON in LP Mode */
+ val = MAX77686_LDO_LOWPOWER_PWRREQ;
+ break;
+ case REGULATOR_MODE_NORMAL: /* ON in Normal Mode */
+ val = max77686_map_normal_mode(max77686, id);
+ break;
+ default:
+ pr_warn("%s: regulator_suspend_mode : 0x%x not supported\n",
+ rdev->desc->name, mode);
+ return -EINVAL;
+ }
+
+ ret = regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ rdev->desc->enable_mask,
+ val << MAX77686_OPMODE_SHIFT);
+ if (ret)
+ return ret;
+
+ max77686->opmode[id] = val;
+ return 0;
+}
+
+static int max77686_enable(struct regulator_dev *rdev)
+{
+ struct max77686_data *max77686 = rdev_get_drvdata(rdev);
+ unsigned int shift;
+ int id = rdev_get_id(rdev);
+
+ shift = max77686_get_opmode_shift(id);
+
+ if (max77686->opmode[id] == MAX77686_OFF_PWRREQ)
+ max77686->opmode[id] = max77686_map_normal_mode(max77686, id);
+
+ return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ rdev->desc->enable_mask,
+ max77686->opmode[id] << shift);
+}
+
+static int max77686_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
+{
+ unsigned int ramp_value = RAMP_RATE_NO_CTRL;
+
+ switch (ramp_delay) {
+ case 1 ... 13750:
+ ramp_value = RAMP_RATE_13P75MV;
+ break;
+ case 13751 ... 27500:
+ ramp_value = RAMP_RATE_27P5MV;
+ break;
+ case 27501 ... 55000:
+ ramp_value = RAMP_RATE_55MV;
+ break;
+ case 55001 ... 100000:
+ break;
+ default:
+ pr_warn("%s: ramp_delay: %d not supported, setting 100000\n",
+ rdev->desc->name, ramp_delay);
+ }
+
+ return regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
+ MAX77686_RAMP_RATE_MASK, ramp_value << 6);
+}
+
+static int max77686_of_parse_cb(struct device_node *np,
+ const struct regulator_desc *desc,
+ struct regulator_config *config)
+{
+ struct max77686_data *max77686 = config->driver_data;
+
+ switch (desc->id) {
+ case MAX77686_BUCK8:
+ case MAX77686_BUCK9:
+ case MAX77686_LDO20 ... MAX77686_LDO22:
+ config->ena_gpio = of_get_named_gpio(np,
+ "maxim,ena-gpios", 0);
+ config->ena_gpio_flags = GPIOF_OUT_INIT_HIGH;
+ config->ena_gpio_initialized = true;
+ break;
+ default:
+ return 0;
+ }
+
+ if (gpio_is_valid(config->ena_gpio)) {
+ set_bit(desc->id, max77686->gpio_enabled);
+
+ return regmap_update_bits(config->regmap, desc->enable_reg,
+ desc->enable_mask,
+ MAX77686_GPIO_CONTROL);
+ }
+
+ return 0;
+}
+
+static struct regulator_ops max77686_ops = {
+ .list_voltage = regulator_list_voltage_linear,
+ .map_voltage = regulator_map_voltage_linear,
+ .is_enabled = regulator_is_enabled_regmap,
+ .enable = max77686_enable,
+ .disable = regulator_disable_regmap,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .set_voltage_time_sel = regulator_set_voltage_time_sel,
+ .set_suspend_mode = max77686_set_suspend_mode,
+};
+
+static struct regulator_ops max77686_ldo_ops = {
+ .list_voltage = regulator_list_voltage_linear,
+ .map_voltage = regulator_map_voltage_linear,
+ .is_enabled = regulator_is_enabled_regmap,
+ .enable = max77686_enable,
+ .disable = regulator_disable_regmap,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .set_voltage_time_sel = regulator_set_voltage_time_sel,
+ .set_suspend_mode = max77686_ldo_set_suspend_mode,
+ .set_suspend_disable = max77686_set_suspend_disable,
+};
+
+static struct regulator_ops max77686_buck1_ops = {
+ .list_voltage = regulator_list_voltage_linear,
+ .map_voltage = regulator_map_voltage_linear,
+ .is_enabled = regulator_is_enabled_regmap,
+ .enable = max77686_enable,
+ .disable = regulator_disable_regmap,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .set_voltage_time_sel = regulator_set_voltage_time_sel,
+ .set_suspend_disable = max77686_set_suspend_disable,
+};
+
+static struct regulator_ops max77686_buck_dvs_ops = {
+ .list_voltage = regulator_list_voltage_linear,
+ .map_voltage = regulator_map_voltage_linear,
+ .is_enabled = regulator_is_enabled_regmap,
+ .enable = max77686_enable,
+ .disable = regulator_disable_regmap,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .set_voltage_time_sel = regulator_set_voltage_time_sel,
+ .set_ramp_delay = max77686_set_ramp_delay,
+ .set_suspend_disable = max77686_set_suspend_disable,
+};
+
+#define regulator_desc_ldo(num) { \
+ .name = "LDO"#num, \
+ .of_match = of_match_ptr("LDO"#num), \
+ .regulators_node = of_match_ptr("voltage-regulators"), \
+ .of_parse_cb = max77686_of_parse_cb, \
+ .id = MAX77686_LDO##num, \
+ .ops = &max77686_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .min_uV = MAX77686_LDO_MINUV, \
+ .uV_step = MAX77686_LDO_UVSTEP, \
+ .ramp_delay = MAX77686_RAMP_DELAY, \
+ .n_voltages = MAX77686_VSEL_MASK + 1, \
+ .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .vsel_mask = MAX77686_VSEL_MASK, \
+ .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .enable_mask = MAX77686_OPMODE_MASK \
+ << MAX77686_OPMODE_SHIFT, \
+}
+#define regulator_desc_lpm_ldo(num) { \
+ .name = "LDO"#num, \
+ .of_match = of_match_ptr("LDO"#num), \
+ .regulators_node = of_match_ptr("voltage-regulators"), \
+ .id = MAX77686_LDO##num, \
+ .ops = &max77686_ldo_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .min_uV = MAX77686_LDO_MINUV, \
+ .uV_step = MAX77686_LDO_UVSTEP, \
+ .ramp_delay = MAX77686_RAMP_DELAY, \
+ .n_voltages = MAX77686_VSEL_MASK + 1, \
+ .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .vsel_mask = MAX77686_VSEL_MASK, \
+ .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .enable_mask = MAX77686_OPMODE_MASK \
+ << MAX77686_OPMODE_SHIFT, \
+}
+#define regulator_desc_ldo_low(num) { \
+ .name = "LDO"#num, \
+ .of_match = of_match_ptr("LDO"#num), \
+ .regulators_node = of_match_ptr("voltage-regulators"), \
+ .id = MAX77686_LDO##num, \
+ .ops = &max77686_ldo_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .min_uV = MAX77686_LDO_LOW_MINUV, \
+ .uV_step = MAX77686_LDO_LOW_UVSTEP, \
+ .ramp_delay = MAX77686_RAMP_DELAY, \
+ .n_voltages = MAX77686_VSEL_MASK + 1, \
+ .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .vsel_mask = MAX77686_VSEL_MASK, \
+ .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .enable_mask = MAX77686_OPMODE_MASK \
+ << MAX77686_OPMODE_SHIFT, \
+}
+#define regulator_desc_ldo1_low(num) { \
+ .name = "LDO"#num, \
+ .of_match = of_match_ptr("LDO"#num), \
+ .regulators_node = of_match_ptr("voltage-regulators"), \
+ .id = MAX77686_LDO##num, \
+ .ops = &max77686_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .min_uV = MAX77686_LDO_LOW_MINUV, \
+ .uV_step = MAX77686_LDO_LOW_UVSTEP, \
+ .ramp_delay = MAX77686_RAMP_DELAY, \
+ .n_voltages = MAX77686_VSEL_MASK + 1, \
+ .vsel_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .vsel_mask = MAX77686_VSEL_MASK, \
+ .enable_reg = MAX77686_REG_LDO1CTRL1 + num - 1, \
+ .enable_mask = MAX77686_OPMODE_MASK \
+ << MAX77686_OPMODE_SHIFT, \
+}
+#define regulator_desc_buck(num) { \
+ .name = "BUCK"#num, \
+ .of_match = of_match_ptr("BUCK"#num), \
+ .regulators_node = of_match_ptr("voltage-regulators"), \
+ .of_parse_cb = max77686_of_parse_cb, \
+ .id = MAX77686_BUCK##num, \
+ .ops = &max77686_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .min_uV = MAX77686_BUCK_MINUV, \
+ .uV_step = MAX77686_BUCK_UVSTEP, \
+ .ramp_delay = MAX77686_RAMP_DELAY, \
+ .n_voltages = MAX77686_VSEL_MASK + 1, \
+ .vsel_reg = MAX77686_REG_BUCK5OUT + (num - 5) * 2, \
+ .vsel_mask = MAX77686_VSEL_MASK, \
+ .enable_reg = MAX77686_REG_BUCK5CTRL + (num - 5) * 2, \
+ .enable_mask = MAX77686_OPMODE_MASK, \
+}
+#define regulator_desc_buck1(num) { \
+ .name = "BUCK"#num, \
+ .of_match = of_match_ptr("BUCK"#num), \
+ .regulators_node = of_match_ptr("voltage-regulators"), \
+ .id = MAX77686_BUCK##num, \
+ .ops = &max77686_buck1_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .min_uV = MAX77686_BUCK_MINUV, \
+ .uV_step = MAX77686_BUCK_UVSTEP, \
+ .ramp_delay = MAX77686_RAMP_DELAY, \
+ .n_voltages = MAX77686_VSEL_MASK + 1, \
+ .vsel_reg = MAX77686_REG_BUCK1OUT, \
+ .vsel_mask = MAX77686_VSEL_MASK, \
+ .enable_reg = MAX77686_REG_BUCK1CTRL, \
+ .enable_mask = MAX77686_OPMODE_MASK, \
+}
+#define regulator_desc_buck_dvs(num) { \
+ .name = "BUCK"#num, \
+ .of_match = of_match_ptr("BUCK"#num), \
+ .regulators_node = of_match_ptr("voltage-regulators"), \
+ .id = MAX77686_BUCK##num, \
+ .ops = &max77686_buck_dvs_ops, \
+ .type = REGULATOR_VOLTAGE, \
+ .owner = THIS_MODULE, \
+ .min_uV = MAX77686_DVS_MINUV, \
+ .uV_step = MAX77686_DVS_UVSTEP, \
+ .ramp_delay = MAX77686_DVS_RAMP_DELAY, \
+ .n_voltages = MAX77686_DVS_VSEL_MASK + 1, \
+ .vsel_reg = MAX77686_REG_BUCK2DVS1 + (num - 2) * 10, \
+ .vsel_mask = MAX77686_DVS_VSEL_MASK, \
+ .enable_reg = MAX77686_REG_BUCK2CTRL1 + (num - 2) * 10, \
+ .enable_mask = MAX77686_OPMODE_MASK \
+ << MAX77686_OPMODE_BUCK234_SHIFT, \
+}
+
+static const struct regulator_desc regulators[] = {
+ regulator_desc_ldo1_low(1),
+ regulator_desc_ldo_low(2),
+ regulator_desc_ldo(3),
+ regulator_desc_ldo(4),
+ regulator_desc_ldo(5),
+ regulator_desc_ldo_low(6),
+ regulator_desc_ldo_low(7),
+ regulator_desc_ldo_low(8),
+ regulator_desc_ldo(9),
+ regulator_desc_lpm_ldo(10),
+ regulator_desc_lpm_ldo(11),
+ regulator_desc_lpm_ldo(12),
+ regulator_desc_ldo(13),
+ regulator_desc_lpm_ldo(14),
+ regulator_desc_ldo_low(15),
+ regulator_desc_lpm_ldo(16),
+ regulator_desc_ldo(17),
+ regulator_desc_ldo(18),
+ regulator_desc_ldo(19),
+ regulator_desc_ldo(20),
+ regulator_desc_ldo(21),
+ regulator_desc_ldo(22),
+ regulator_desc_ldo(23),
+ regulator_desc_ldo(24),
+ regulator_desc_ldo(25),
+ regulator_desc_ldo(26),
+ regulator_desc_buck1(1),
+ regulator_desc_buck_dvs(2),
+ regulator_desc_buck_dvs(3),
+ regulator_desc_buck_dvs(4),
+ regulator_desc_buck(5),
+ regulator_desc_buck(6),
+ regulator_desc_buck(7),
+ regulator_desc_buck(8),
+ regulator_desc_buck(9),
+};
+
+static int max77686_pmic_probe(struct platform_device *pdev)
+{
+ struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
+ struct max77686_data *max77686;
+ int i;
+ struct regulator_config config = { };
+
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+
+ max77686 = devm_kzalloc(&pdev->dev, sizeof(struct max77686_data),
+ GFP_KERNEL);
+ if (!max77686)
+ return -ENOMEM;
+
+ config.dev = iodev->dev;
+ config.regmap = iodev->regmap;
+ config.driver_data = max77686;
+ platform_set_drvdata(pdev, max77686);
+
+ for (i = 0; i < MAX77686_REGULATORS; i++) {
+ struct regulator_dev *rdev;
+ int id = regulators[i].id;
+
+ max77686->opmode[id] = MAX77686_NORMAL;
+ rdev = devm_regulator_register(&pdev->dev,
+ &regulators[i], &config);
+ if (IS_ERR(rdev)) {
+ int ret = PTR_ERR(rdev);
+ dev_err(&pdev->dev,
+ "regulator init failed for %d: %d\n", i, ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct platform_device_id max77686_pmic_id[] = {
+ {"max77686-pmic", 0},
+ { },
+};
+MODULE_DEVICE_TABLE(platform, max77686_pmic_id);
+
+static struct platform_driver max77686_pmic_driver = {
+ .driver = {
+ .name = "max77686-pmic",
+ },
+ .probe = max77686_pmic_probe,
+ .id_table = max77686_pmic_id,
+};
+
+static int __init max77686_pmic_init(void)
+{
+ return platform_driver_register(&max77686_pmic_driver);
+}
+subsys_initcall(max77686_pmic_init);
+
+static void __exit max77686_pmic_cleanup(void)
+{
+ platform_driver_unregister(&max77686_pmic_driver);
+}
+module_exit(max77686_pmic_cleanup);
+
+MODULE_DESCRIPTION("MAXIM 77686 Regulator Driver");
+MODULE_AUTHOR("Chiwoong Byun <woong.byun@samsung.com>");
+MODULE_LICENSE("GPL");