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authorAxel Lin <axel.lin@gmail.com>2010-09-16 16:48:49 +0800
committerLiam Girdwood <lrg@slimlogic.co.uk>2010-10-28 22:40:31 +0100
commit5976f0959d5251ae5b4db848eaa2f42a19e98652 (patch)
treeee8396999d0b037a72bc5b8b8e5c8f18e10c0d49 /drivers/regulator/lp3972.c
parent202f4f53e503ae09b431459131b5b3a99fa6d839 (diff)
Regulator: LP3972 PMIC regulator driver
This patch adds regulator drivers for National Semiconductors LP3972 PMIC. This LP3972 PMIC controller has 3 DC/DC voltage converters and 5 low drop-out (LDO) regulators. LP3972 PMIC controller uses I2C interface. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Diffstat (limited to 'drivers/regulator/lp3972.c')
-rw-r--r--drivers/regulator/lp3972.c649
1 files changed, 649 insertions, 0 deletions
diff --git a/drivers/regulator/lp3972.c b/drivers/regulator/lp3972.c
new file mode 100644
index 00000000000..0d9b47569c1
--- /dev/null
+++ b/drivers/regulator/lp3972.c
@@ -0,0 +1,649 @@
+/*
+ * 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/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;
+ int num_regulators;
+ struct regulator_dev **rdev;
+};
+
+/* 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 int ldo1_voltage_map[] = {
+ 1700, 1725, 1750, 1775, 1800, 1825, 1850, 1875,
+ 1900, 1925, 1950, 1975, 2000,
+};
+
+static const int ldo23_voltage_map[] = {
+ 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
+ 2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300,
+};
+
+static const int ldo4_voltage_map[] = {
+ 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350,
+ 1400, 1500, 1800, 1900, 2500, 2800, 3000, 3300,
+};
+
+static const int ldo5_voltage_map[] = {
+ 0, 0, 0, 0, 0, 850, 875, 900,
+ 925, 950, 975, 1000, 1025, 1050, 1075, 1100,
+ 1125, 1150, 1175, 1200, 1225, 1250, 1275, 1300,
+ 1325, 1350, 1375, 1400, 1425, 1450, 1475, 1500,
+};
+
+static const int buck1_voltage_map[] = {
+ 725, 750, 775, 800, 825, 850, 875, 900,
+ 925, 950, 975, 1000, 1025, 1050, 1075, 1100,
+ 1125, 1150, 1175, 1200, 1225, 1250, 1275, 1300,
+ 1325, 1350, 1375, 1400, 1425, 1450, 1475, 1500,
+};
+
+static const int buck23_voltage_map[] = {
+ 0, 800, 850, 900, 950, 1000, 1050, 1100,
+ 1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500,
+ 1550, 1600, 1650, 1700, 1800, 1900, 2500, 2800,
+ 3000, 3300,
+};
+
+static const int *ldo_voltage_map[] = {
+ ldo1_voltage_map,
+ ldo23_voltage_map,
+ ldo23_voltage_map,
+ ldo4_voltage_map,
+ ldo5_voltage_map,
+};
+
+static const int *buck_voltage_map[] = {
+ buck1_voltage_map,
+ buck23_voltage_map,
+ buck23_voltage_map,
+};
+
+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_VOL_VALUE_MAP(x) (ldo_voltage_map[x])
+#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_VALUE_MAP(x) (buck_voltage_map[x])
+#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
+#define LP3972_BUCK_VOL_MIN_IDX(x) ((x) ? 0x01 : 0x00)
+#define LP3972_BUCK_VOL_MAX_IDX(x) ((x) ? 0x19 : 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 -EIO;
+
+ *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_list_voltage(struct regulator_dev *dev, unsigned index)
+{
+ int ldo = rdev_get_id(dev) - LP3972_LDO1;
+ return 1000 * LP3972_LDO_VOL_VALUE_MAP(ldo)[index];
+}
+
+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(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 1000 * LP3972_LDO_VOL_VALUE_MAP(ldo)[val];
+}
+
+static int lp3972_ldo_set_voltage(struct regulator_dev *dev,
+ int min_uV, int max_uV)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3972_LDO1;
+ int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
+ const int *vol_map = LP3972_LDO_VOL_VALUE_MAP(ldo);
+ u16 val;
+ int shift, ret;
+
+ if (min_vol < vol_map[LP3972_LDO_VOL_MIN_IDX(ldo)] ||
+ min_vol > vol_map[LP3972_LDO_VOL_MAX_IDX(ldo)])
+ return -EINVAL;
+
+ for (val = LP3972_LDO_VOL_MIN_IDX(ldo);
+ val <= LP3972_LDO_VOL_MAX_IDX(ldo); val++)
+ if (vol_map[val] >= min_vol)
+ break;
+
+ if (val > LP3972_LDO_VOL_MAX_IDX(ldo) || vol_map[val] > max_vol)
+ return -EINVAL;
+
+ shift = LP3972_LDO_VOL_CONTR_SHIFT(ldo);
+ ret = lp3972_set_bits(lp3972, LP3972_LDO_VOL_CONTR_REG(ldo),
+ LP3972_LDO_VOL_MASK(ldo) << shift, val << shift);
+
+ if (ret)
+ return ret;
+
+ 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 = lp3972_ldo_list_voltage,
+ .is_enabled = lp3972_ldo_is_enabled,
+ .enable = lp3972_ldo_enable,
+ .disable = lp3972_ldo_disable,
+ .get_voltage = lp3972_ldo_get_voltage,
+ .set_voltage = lp3972_ldo_set_voltage,
+};
+
+static int lp3972_dcdc_list_voltage(struct regulator_dev *dev, unsigned index)
+{
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ return 1000 * buck_voltage_map[buck][index];
+}
+
+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(struct regulator_dev *dev)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ u16 reg;
+ int val;
+
+ reg = lp3972_reg_read(lp3972, LP3972_BUCK_VOL1_REG(buck));
+ reg &= LP3972_BUCK_VOL_MASK;
+ if (reg <= LP3972_BUCK_VOL_MAX_IDX(buck))
+ val = 1000 * buck_voltage_map[buck][reg];
+ else {
+ val = 0;
+ dev_warn(&dev->dev, "chip reported incorrect voltage value.\n");
+ }
+
+ return val;
+}
+
+static int lp3972_dcdc_set_voltage(struct regulator_dev *dev,
+ int min_uV, int max_uV)
+{
+ struct lp3972 *lp3972 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3972_DCDC1;
+ int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
+ const int *vol_map = buck_voltage_map[buck];
+ u16 val;
+ int ret;
+
+ if (min_vol < vol_map[LP3972_BUCK_VOL_MIN_IDX(buck)] ||
+ min_vol > vol_map[LP3972_BUCK_VOL_MAX_IDX(buck)])
+ return -EINVAL;
+
+ for (val = LP3972_BUCK_VOL_MIN_IDX(buck);
+ val <= LP3972_BUCK_VOL_MAX_IDX(buck); val++)
+ if (vol_map[val] >= min_vol)
+ break;
+
+ if (val > LP3972_BUCK_VOL_MAX_IDX(buck) ||
+ vol_map[val] > max_vol)
+ return -EINVAL;
+
+ ret = lp3972_set_bits(lp3972, LP3972_BUCK_VOL1_REG(buck),
+ LP3972_BUCK_VOL_MASK, val);
+ 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 = lp3972_dcdc_list_voltage,
+ .is_enabled = lp3972_dcdc_is_enabled,
+ .enable = lp3972_dcdc_enable,
+ .disable = lp3972_dcdc_disable,
+ .get_voltage = lp3972_dcdc_get_voltage,
+ .set_voltage = lp3972_dcdc_set_voltage,
+};
+
+static struct regulator_desc regulators[] = {
+ {
+ .name = "LDO1",
+ .id = LP3972_LDO1,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(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),
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO3",
+ .id = LP3972_LDO3,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(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),
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO5",
+ .id = LP3972_LDO5,
+ .ops = &lp3972_ldo_ops,
+ .n_voltages = ARRAY_SIZE(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),
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "DCDC2",
+ .id = LP3972_DCDC2,
+ .ops = &lp3972_dcdc_ops,
+ .n_voltages = ARRAY_SIZE(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),
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int setup_regulators(struct lp3972 *lp3972,
+ struct lp3972_platform_data *pdata)
+{
+ int i, err;
+
+ lp3972->num_regulators = pdata->num_regulators;
+ lp3972->rdev = kcalloc(pdata->num_regulators,
+ sizeof(struct regulator_dev *), GFP_KERNEL);
+ if (!lp3972->rdev) {
+ err = -ENOMEM;
+ goto err_nomem;
+ }
+
+ /* Instantiate the regulators */
+ for (i = 0; i < pdata->num_regulators; i++) {
+ struct lp3972_regulator_subdev *reg = &pdata->regulators[i];
+ lp3972->rdev[i] = regulator_register(&regulators[reg->id],
+ lp3972->dev, reg->initdata, lp3972);
+
+ if (IS_ERR(lp3972->rdev[i])) {
+ err = PTR_ERR(lp3972->rdev[i]);
+ dev_err(lp3972->dev, "regulator init failed: %d\n",
+ err);
+ goto error;
+ }
+ }
+
+ return 0;
+error:
+ while (--i >= 0)
+ regulator_unregister(lp3972->rdev[i]);
+ kfree(lp3972->rdev);
+ lp3972->rdev = NULL;
+err_nomem:
+ return err;
+}
+
+static int __devinit lp3972_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct lp3972 *lp3972;
+ struct lp3972_platform_data *pdata = i2c->dev.platform_data;
+ int ret;
+ u16 val;
+
+ if (!pdata) {
+ dev_dbg(&i2c->dev, "No platform init data supplied\n");
+ return -ENODEV;
+ }
+
+ lp3972 = kzalloc(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;
+ if (ret < 0) {
+ dev_err(&i2c->dev, "failed to detect device\n");
+ goto err_detect;
+ }
+
+ ret = setup_regulators(lp3972, pdata);
+ if (ret < 0)
+ goto err_detect;
+
+ i2c_set_clientdata(i2c, lp3972);
+ return 0;
+
+err_detect:
+ kfree(lp3972);
+ return ret;
+}
+
+static int __devexit lp3972_i2c_remove(struct i2c_client *i2c)
+{
+ struct lp3972 *lp3972 = i2c_get_clientdata(i2c);
+ int i;
+
+ for (i = 0; i < lp3972->num_regulators; i++)
+ regulator_unregister(lp3972->rdev[i]);
+ kfree(lp3972->rdev);
+ kfree(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,
+ .remove = __devexit_p(lp3972_i2c_remove),
+ .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");