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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/regulator/lp3972.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/regulator/lp3972.c')
-rw-r--r--kernel/drivers/regulator/lp3972.c573
1 files changed, 573 insertions, 0 deletions
diff --git a/kernel/drivers/regulator/lp3972.c b/kernel/drivers/regulator/lp3972.c
new file mode 100644
index 000000000..aea485afc
--- /dev/null
+++ b/kernel/drivers/regulator/lp3972.c
@@ -0,0 +1,573 @@
+/*
+ * Regulator driver for National Semiconductors LP3972 PMIC chip
+ *
+ * Based on lp3971.c
+ *
+ * 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/bug.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/lp3972.h>
+#include <linux/slab.h>
+
+struct lp3972 {
+ struct device *dev;
+ struct mutex io_lock;
+ struct i2c_client *i2c;
+};
+
+/* LP3972 Control Registers */
+#define LP3972_SCR_REG 0x07
+#define LP3972_OVER1_REG 0x10
+#define LP3972_OVSR1_REG 0x11
+#define LP3972_OVER2_REG 0x12
+#define LP3972_OVSR2_REG 0x13
+#define LP3972_VCC1_REG 0x20
+#define LP3972_ADTV1_REG 0x23
+#define LP3972_ADTV2_REG 0x24
+#define LP3972_AVRC_REG 0x25
+#define LP3972_CDTC1_REG 0x26
+#define LP3972_CDTC2_REG 0x27
+#define LP3972_SDTV1_REG 0x29
+#define LP3972_SDTV2_REG 0x2A
+#define LP3972_MDTV1_REG 0x32
+#define LP3972_MDTV2_REG 0x33
+#define LP3972_L2VCR_REG 0x39
+#define LP3972_L34VCR_REG 0x3A
+#define LP3972_SCR1_REG 0x80
+#define LP3972_SCR2_REG 0x81
+#define LP3972_OEN3_REG 0x82
+#define LP3972_OSR3_REG 0x83
+#define LP3972_LOER4_REG 0x84
+#define LP3972_B2TV_REG 0x85
+#define LP3972_B3TV_REG 0x86
+#define LP3972_B32RC_REG 0x87
+#define LP3972_ISRA_REG 0x88
+#define LP3972_BCCR_REG 0x89
+#define LP3972_II1RR_REG 0x8E
+#define LP3972_II2RR_REG 0x8F
+
+#define LP3972_SYS_CONTROL1_REG LP3972_SCR1_REG
+/* System control register 1 initial value,
+ * bits 5, 6 and 7 are EPROM programmable */
+#define SYS_CONTROL1_INIT_VAL 0x02
+#define SYS_CONTROL1_INIT_MASK 0x1F
+
+#define LP3972_VOL_CHANGE_REG LP3972_VCC1_REG
+#define LP3972_VOL_CHANGE_FLAG_GO 0x01
+#define LP3972_VOL_CHANGE_FLAG_MASK 0x03
+
+/* LDO output enable mask */
+#define LP3972_OEN3_L1EN BIT(0)
+#define LP3972_OVER2_LDO2_EN BIT(2)
+#define LP3972_OVER2_LDO3_EN BIT(3)
+#define LP3972_OVER2_LDO4_EN BIT(4)
+#define LP3972_OVER1_S_EN BIT(2)
+
+static const unsigned int ldo1_voltage_map[] = {
+ 1700000, 1725000, 1750000, 1775000, 1800000, 1825000, 1850000, 1875000,
+ 1900000, 1925000, 1950000, 1975000, 2000000,
+};
+
+static const unsigned int ldo23_voltage_map[] = {
+ 1800000, 1900000, 2000000, 2100000, 2200000, 2300000, 2400000, 2500000,
+ 2600000, 2700000, 2800000, 2900000, 3000000, 3100000, 3200000, 3300000,
+};
+
+static const unsigned int ldo4_voltage_map[] = {
+ 1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000, 1350000,
+ 1400000, 1500000, 1800000, 1900000, 2500000, 2800000, 3000000, 3300000,
+};
+
+static const unsigned int ldo5_voltage_map[] = {
+ 0, 0, 0, 0, 0, 850000, 875000, 900000,
+ 925000, 950000, 975000, 1000000, 1025000, 1050000, 1075000, 1100000,
+ 1125000, 1150000, 1175000, 1200000, 1225000, 1250000, 1275000, 1300000,
+ 1325000, 1350000, 1375000, 1400000, 1425000, 1450000, 1475000, 1500000,
+};
+
+static const unsigned int buck1_voltage_map[] = {
+ 725000, 750000, 775000, 800000, 825000, 850000, 875000, 900000,
+ 925000, 950000, 975000, 1000000, 1025000, 1050000, 1075000, 1100000,
+ 1125000, 1150000, 1175000, 1200000, 1225000, 1250000, 1275000, 1300000,
+ 1325000, 1350000, 1375000, 1400000, 1425000, 1450000, 1475000, 1500000,
+};
+
+static const unsigned int buck23_voltage_map[] = {
+ 0, 800000, 850000, 900000, 950000, 1000000, 1050000, 1100000,
+ 1150000, 1200000, 1250000, 1300000, 1350000, 1400000, 1450000, 1500000,
+ 1550000, 1600000, 1650000, 1700000, 1800000, 1900000, 2500000, 2800000,
+ 3000000, 3300000,
+};
+
+static const int ldo_output_enable_mask[] = {
+ LP3972_OEN3_L1EN,
+ LP3972_OVER2_LDO2_EN,
+ LP3972_OVER2_LDO3_EN,
+ LP3972_OVER2_LDO4_EN,
+ LP3972_OVER1_S_EN,
+};
+
+static const int ldo_output_enable_addr[] = {
+ LP3972_OEN3_REG,
+ LP3972_OVER2_REG,
+ LP3972_OVER2_REG,
+ LP3972_OVER2_REG,
+ LP3972_OVER1_REG,
+};
+
+static const int ldo_vol_ctl_addr[] = {
+ LP3972_MDTV1_REG,
+ LP3972_L2VCR_REG,
+ LP3972_L34VCR_REG,
+ LP3972_L34VCR_REG,
+ LP3972_SDTV1_REG,
+};
+
+static const int buck_vol_enable_addr[] = {
+ LP3972_OVER1_REG,
+ LP3972_OEN3_REG,
+ LP3972_OEN3_REG,
+};
+
+static const int buck_base_addr[] = {
+ LP3972_ADTV1_REG,
+ LP3972_B2TV_REG,
+ LP3972_B3TV_REG,
+};
+
+#define LP3972_LDO_OUTPUT_ENABLE_MASK(x) (ldo_output_enable_mask[x])
+#define LP3972_LDO_OUTPUT_ENABLE_REG(x) (ldo_output_enable_addr[x])
+
+/* LDO voltage control registers shift:
+ LP3972_LDO1 -> 0, LP3972_LDO2 -> 4
+ LP3972_LDO3 -> 0, LP3972_LDO4 -> 4
+ LP3972_LDO5 -> 0
+*/
+#define LP3972_LDO_VOL_CONTR_SHIFT(x) (((x) & 1) << 2)
+#define LP3972_LDO_VOL_CONTR_REG(x) (ldo_vol_ctl_addr[x])
+#define LP3972_LDO_VOL_CHANGE_SHIFT(x) ((x) ? 4 : 6)
+
+#define LP3972_LDO_VOL_MASK(x) (((x) % 4) ? 0x0f : 0x1f)
+#define LP3972_LDO_VOL_MIN_IDX(x) (((x) == 4) ? 0x05 : 0x00)
+#define LP3972_LDO_VOL_MAX_IDX(x) ((x) ? (((x) == 4) ? 0x1f : 0x0f) : 0x0c)
+
+#define LP3972_BUCK_VOL_ENABLE_REG(x) (buck_vol_enable_addr[x])
+#define LP3972_BUCK_VOL1_REG(x) (buck_base_addr[x])
+#define LP3972_BUCK_VOL_MASK 0x1f
+
+static int lp3972_i2c_read(struct i2c_client *i2c, char reg, int count,
+ u16 *dest)
+{
+ int ret;
+
+ if (count != 1)
+ return -EIO;
+ ret = i2c_smbus_read_byte_data(i2c, reg);
+ if (ret < 0)
+ return ret;
+
+ *dest = ret;
+ return 0;
+}
+
+static int lp3972_i2c_write(struct i2c_client *i2c, char reg, int count,
+ const u16 *src)
+{
+ if (count != 1)
+ return -EIO;
+ return i2c_smbus_write_byte_data(i2c, reg, *src);
+}
+
+static u8 lp3972_reg_read(struct lp3972 *lp3972, u8 reg)
+{
+ u16 val = 0;
+
+ mutex_lock(&lp3972->io_lock);
+
+ lp3972_i2c_read(lp3972->i2c, reg, 1, &val);
+
+ dev_dbg(lp3972->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
+ (unsigned)val & 0xff);
+
+ mutex_unlock(&lp3972->io_lock);
+
+ return val & 0xff;
+}
+
+static int lp3972_set_bits(struct lp3972 *lp3972, u8 reg, u16 mask, u16 val)
+{
+ u16 tmp;
+ int ret;
+
+ mutex_lock(&lp3972->io_lock);
+
+ ret = lp3972_i2c_read(lp3972->i2c, reg, 1, &tmp);
+ tmp = (tmp & ~mask) | val;
+ if (ret == 0) {
+ ret = lp3972_i2c_write(lp3972->i2c, reg, 1, &tmp);
+ dev_dbg(lp3972->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
+ (unsigned)val & 0xff);
+ }
+ mutex_unlock(&lp3972->io_lock);
+
+ return ret;
+}
+
+static int lp3972_ldo_is_enabled(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3972_LDO1;
+ u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
+ u16 val;
+
+ val = lp3972_reg_read(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo));
+ return !!(val & mask);
+}
+
+static int lp3972_ldo_enable(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3972_LDO1;
+ u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
+
+ return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
+ mask, mask);
+}
+
+static int lp3972_ldo_disable(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3972_LDO1;
+ u16 mask = LP3972_LDO_OUTPUT_ENABLE_MASK(ldo);
+
+ return lp3972_set_bits(lp3972, LP3972_LDO_OUTPUT_ENABLE_REG(ldo),
+ mask, 0);
+}
+
+static int lp3972_ldo_get_voltage_sel(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3972_LDO1;
+ u16 mask = LP3972_LDO_VOL_MASK(ldo);
+ u16 val, reg;
+
+ reg = lp3972_reg_read(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo));
+ val = (reg >> LP3972_LDO_VOL_CONTR_SHIFT(ldo)) & mask;
+
+ return val;
+}
+
+static int lp3972_ldo_set_voltage_sel(struct regulator_dev *dev,
+ unsigned int selector)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3972_LDO1;
+ int shift, ret;
+
+ shift = LP3972_LDO_VOL_CONTR_SHIFT(ldo);
+ ret = lp3972_set_bits(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo),
+ LP3972_LDO_VOL_MASK(ldo) << shift, selector << shift);
+
+ if (ret)
+ return ret;
+
+ /*
+ * LDO1 and LDO5 support voltage control by either target voltage1
+ * or target voltage2 register.
+ * We use target voltage1 register for LDO1 and LDO5 in this driver.
+ * We need to update voltage change control register(0x20) to enable
+ * LDO1 and LDO5 to change to their programmed target values.
+ */
+ switch (ldo) {
+ case LP3972_LDO1:
+ case LP3972_LDO5:
+ shift = LP3972_LDO_VOL_CHANGE_SHIFT(ldo);
+ ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
+ LP3972_VOL_CHANGE_FLAG_MASK << shift,
+ LP3972_VOL_CHANGE_FLAG_GO << shift);
+ if (ret)
+ return ret;
+
+ ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
+ LP3972_VOL_CHANGE_FLAG_MASK << shift, 0);
+ break;
+ }
+
+ return ret;
+}
+
+static struct regulator_ops lp3972_ldo_ops = {
+ .list_voltage = regulator_list_voltage_table,
+ .map_voltage = regulator_map_voltage_ascend,
+ .is_enabled = lp3972_ldo_is_enabled,
+ .enable = lp3972_ldo_enable,
+ .disable = lp3972_ldo_disable,
+ .get_voltage_sel = lp3972_ldo_get_voltage_sel,
+ .set_voltage_sel = lp3972_ldo_set_voltage_sel,
+};
+
+static int lp3972_dcdc_is_enabled(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ u16 mask = 1 << (buck * 2);
+ u16 val;
+
+ val = lp3972_reg_read(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck));
+ return !!(val & mask);
+}
+
+static int lp3972_dcdc_enable(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ u16 mask = 1 << (buck * 2);
+ u16 val;
+
+ val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
+ mask, mask);
+ return val;
+}
+
+static int lp3972_dcdc_disable(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ u16 mask = 1 << (buck * 2);
+ u16 val;
+
+ val = lp3972_set_bits(lp3972, LP3972_BUCK_VOL_ENABLE_REG(buck),
+ mask, 0);
+ return val;
+}
+
+static int lp3972_dcdc_get_voltage_sel(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ u16 reg;
+
+ reg = lp3972_reg_read(lp3972, LP3972_BUCK_VOL1_REG(buck));
+ reg &= LP3972_BUCK_VOL_MASK;
+
+ return reg;
+}
+
+static int lp3972_dcdc_set_voltage_sel(struct regulator_dev *dev,
+ unsigned int selector)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ int ret;
+
+ ret = lp3972_set_bits(lp3972, LP3972_BUCK_VOL1_REG(buck),
+ LP3972_BUCK_VOL_MASK, selector);
+ if (ret)
+ return ret;
+
+ if (buck != 0)
+ return ret;
+
+ ret = lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
+ LP3972_VOL_CHANGE_FLAG_MASK, LP3972_VOL_CHANGE_FLAG_GO);
+ if (ret)
+ return ret;
+
+ return lp3972_set_bits(lp3972, LP3972_VOL_CHANGE_REG,
+ LP3972_VOL_CHANGE_FLAG_MASK, 0);
+}
+
+static struct regulator_ops lp3972_dcdc_ops = {
+ .list_voltage = regulator_list_voltage_table,
+ .map_voltage = regulator_map_voltage_ascend,
+ .is_enabled = lp3972_dcdc_is_enabled,
+ .enable = lp3972_dcdc_enable,
+ .disable = lp3972_dcdc_disable,
+ .get_voltage_sel = lp3972_dcdc_get_voltage_sel,
+ .set_voltage_sel = lp3972_dcdc_set_voltage_sel,
+};
+
+static const struct regulator_desc regulators[] = {
+ {
+ .name = "LDO1",
+ .id = LP3972_LDO1,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(ldo1_voltage_map),
+ .volt_table = ldo1_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO2",
+ .id = LP3972_LDO2,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(ldo23_voltage_map),
+ .volt_table = ldo23_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO3",
+ .id = LP3972_LDO3,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(ldo23_voltage_map),
+ .volt_table = ldo23_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO4",
+ .id = LP3972_LDO4,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(ldo4_voltage_map),
+ .volt_table = ldo4_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO5",
+ .id = LP3972_LDO5,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(ldo5_voltage_map),
+ .volt_table = ldo5_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "DCDC1",
+ .id = LP3972_DCDC1,
+ .ops = &lp3972_dcdc_ops,
+ .n_voltages = ARRAY_SIZE(buck1_voltage_map),
+ .volt_table = buck1_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "DCDC2",
+ .id = LP3972_DCDC2,
+ .ops = &lp3972_dcdc_ops,
+ .n_voltages = ARRAY_SIZE(buck23_voltage_map),
+ .volt_table = buck23_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "DCDC3",
+ .id = LP3972_DCDC3,
+ .ops = &lp3972_dcdc_ops,
+ .n_voltages = ARRAY_SIZE(buck23_voltage_map),
+ .volt_table = buck23_voltage_map,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int setup_regulators(struct lp3972 *lp3972,
+ struct lp3972_platform_data *pdata)
+{
+ int i, err;
+
+ /* Instantiate the regulators */
+ for (i = 0; i < pdata->num_regulators; i++) {
+ struct lp3972_regulator_subdev *reg = &pdata->regulators[i];
+ struct regulator_config config = { };
+ struct regulator_dev *rdev;
+
+ config.dev = lp3972->dev;
+ config.init_data = reg->initdata;
+ config.driver_data = lp3972;
+
+ rdev = devm_regulator_register(lp3972->dev,
+ &regulators[reg->id], &config);
+ if (IS_ERR(rdev)) {
+ err = PTR_ERR(rdev);
+ dev_err(lp3972->dev, "regulator init failed: %d\n",
+ err);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int lp3972_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct lp3972 *lp3972;
+ struct lp3972_platform_data *pdata = dev_get_platdata(&i2c->dev);
+ int ret;
+ u16 val;
+
+ if (!pdata) {
+ dev_dbg(&i2c->dev, "No platform init data supplied\n");
+ return -ENODEV;
+ }
+
+ lp3972 = devm_kzalloc(&i2c->dev, sizeof(struct lp3972), GFP_KERNEL);
+ if (!lp3972)
+ return -ENOMEM;
+
+ lp3972->i2c = i2c;
+ lp3972->dev = &i2c->dev;
+
+ mutex_init(&lp3972->io_lock);
+
+ /* Detect LP3972 */
+ ret = lp3972_i2c_read(i2c, LP3972_SYS_CONTROL1_REG, 1, &val);
+ if (ret == 0 &&
+ (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL) {
+ ret = -ENODEV;
+ dev_err(&i2c->dev, "chip reported: val = 0x%x\n", val);
+ }
+ if (ret < 0) {
+ dev_err(&i2c->dev, "failed to detect device. ret = %d\n", ret);
+ return ret;
+ }
+
+ ret = setup_regulators(lp3972, pdata);
+ if (ret < 0)
+ return ret;
+
+ i2c_set_clientdata(i2c, lp3972);
+ return 0;
+}
+
+static const struct i2c_device_id lp3972_i2c_id[] = {
+ { "lp3972", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lp3972_i2c_id);
+
+static struct i2c_driver lp3972_i2c_driver = {
+ .driver = {
+ .name = "lp3972",
+ .owner = THIS_MODULE,
+ },
+ .probe = lp3972_i2c_probe,
+ .id_table = lp3972_i2c_id,
+};
+
+static int __init lp3972_module_init(void)
+{
+ return i2c_add_driver(&lp3972_i2c_driver);
+}
+subsys_initcall(lp3972_module_init);
+
+static void __exit lp3972_module_exit(void)
+{
+ i2c_del_driver(&lp3972_i2c_driver);
+}
+module_exit(lp3972_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Axel Lin <axel.lin@gmail.com>");
+MODULE_DESCRIPTION("LP3972 PMIC driver");