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linux-next/drivers/regulator/twl-regulator.c
Balaji T K 8e6de4a302 regulator: twl: add clk32kg to twl-regulator
In OMAP4 Blaze and Panda, 32KHz clock to WLAN is supplied from Phoenix
TWL6030. The 32KHz clock state (ON/OFF) is configured in
CLK32KG_CFG_[GRP, TRANS, STATE] register. This follows the same register
programming model as other regulators in TWL6030. So add CLK32KG as pseudo
regulator.

Signed-off-by: Balaji T K <balajitk@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2011-03-23 10:41:48 +01:00

702 lines
18 KiB
C

/*
* twl-regulator.c -- support regulators in twl4030/twl6030 family chips
*
* Copyright (C) 2008 David Brownell
*
* 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.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/i2c/twl.h>
/*
* The TWL4030/TW5030/TPS659x0/TWL6030 family chips include power management, a
* USB OTG transceiver, an RTC, ADC, PWM, and lots more. Some versions
* include an audio codec, battery charger, and more voltage regulators.
* These chips are often used in OMAP-based systems.
*
* This driver implements software-based resource control for various
* voltage regulators. This is usually augmented with state machine
* based control.
*/
struct twlreg_info {
/* start of regulator's PM_RECEIVER control register bank */
u8 base;
/* twl resource ID, for resource control state machine */
u8 id;
/* voltage in mV = table[VSEL]; table_len must be a power-of-two */
u8 table_len;
const u16 *table;
/* regulator specific turn-on delay */
u16 delay;
/* State REMAP default configuration */
u8 remap;
/* chip constraints on regulator behavior */
u16 min_mV;
u16 max_mV;
/* used by regulator core */
struct regulator_desc desc;
};
/* LDO control registers ... offset is from the base of its register bank.
* The first three registers of all power resource banks help hardware to
* manage the various resource groups.
*/
/* Common offset in TWL4030/6030 */
#define VREG_GRP 0
/* TWL4030 register offsets */
#define VREG_TYPE 1
#define VREG_REMAP 2
#define VREG_DEDICATED 3 /* LDO control */
/* TWL6030 register offsets */
#define VREG_TRANS 1
#define VREG_STATE 2
#define VREG_VOLTAGE 3
/* TWL6030 Misc register offsets */
#define VREG_BC_ALL 1
#define VREG_BC_REF 2
#define VREG_BC_PROC 3
#define VREG_BC_CLK_RST 4
static inline int
twlreg_read(struct twlreg_info *info, unsigned slave_subgp, unsigned offset)
{
u8 value;
int status;
status = twl_i2c_read_u8(slave_subgp,
&value, info->base + offset);
return (status < 0) ? status : value;
}
static inline int
twlreg_write(struct twlreg_info *info, unsigned slave_subgp, unsigned offset,
u8 value)
{
return twl_i2c_write_u8(slave_subgp,
value, info->base + offset);
}
/*----------------------------------------------------------------------*/
/* generic power resource operations, which work on all regulators */
static int twlreg_grp(struct regulator_dev *rdev)
{
return twlreg_read(rdev_get_drvdata(rdev), TWL_MODULE_PM_RECEIVER,
VREG_GRP);
}
/*
* Enable/disable regulators by joining/leaving the P1 (processor) group.
* We assume nobody else is updating the DEV_GRP registers.
*/
/* definition for 4030 family */
#define P3_GRP_4030 BIT(7) /* "peripherals" */
#define P2_GRP_4030 BIT(6) /* secondary processor, modem, etc */
#define P1_GRP_4030 BIT(5) /* CPU/Linux */
/* definition for 6030 family */
#define P3_GRP_6030 BIT(2) /* secondary processor, modem, etc */
#define P2_GRP_6030 BIT(1) /* "peripherals" */
#define P1_GRP_6030 BIT(0) /* CPU/Linux */
static int twlreg_is_enabled(struct regulator_dev *rdev)
{
int state = twlreg_grp(rdev);
if (state < 0)
return state;
if (twl_class_is_4030())
state &= P1_GRP_4030;
else
state &= P1_GRP_6030;
return state;
}
static int twlreg_enable(struct regulator_dev *rdev)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
int grp;
int ret;
grp = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_GRP);
if (grp < 0)
return grp;
if (twl_class_is_4030())
grp |= P1_GRP_4030;
else
grp |= P1_GRP_6030;
ret = twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_GRP, grp);
udelay(info->delay);
return ret;
}
static int twlreg_disable(struct regulator_dev *rdev)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
int grp;
grp = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_GRP);
if (grp < 0)
return grp;
if (twl_class_is_4030())
grp &= ~(P1_GRP_4030 | P2_GRP_4030 | P3_GRP_4030);
else
grp &= ~(P1_GRP_6030 | P2_GRP_6030 | P3_GRP_6030);
return twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_GRP, grp);
}
static int twlreg_get_status(struct regulator_dev *rdev)
{
int state = twlreg_grp(rdev);
if (twl_class_is_6030())
return 0; /* FIXME return for 6030 regulator */
if (state < 0)
return state;
state &= 0x0f;
/* assume state != WARM_RESET; we'd not be running... */
if (!state)
return REGULATOR_STATUS_OFF;
return (state & BIT(3))
? REGULATOR_STATUS_NORMAL
: REGULATOR_STATUS_STANDBY;
}
static int twlreg_set_mode(struct regulator_dev *rdev, unsigned mode)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
unsigned message;
int status;
if (twl_class_is_6030())
return 0; /* FIXME return for 6030 regulator */
/* We can only set the mode through state machine commands... */
switch (mode) {
case REGULATOR_MODE_NORMAL:
message = MSG_SINGULAR(DEV_GRP_P1, info->id, RES_STATE_ACTIVE);
break;
case REGULATOR_MODE_STANDBY:
message = MSG_SINGULAR(DEV_GRP_P1, info->id, RES_STATE_SLEEP);
break;
default:
return -EINVAL;
}
/* Ensure the resource is associated with some group */
status = twlreg_grp(rdev);
if (status < 0)
return status;
if (!(status & (P3_GRP_4030 | P2_GRP_4030 | P1_GRP_4030)))
return -EACCES;
status = twl_i2c_write_u8(TWL_MODULE_PM_MASTER,
message >> 8, TWL4030_PM_MASTER_PB_WORD_MSB);
if (status < 0)
return status;
return twl_i2c_write_u8(TWL_MODULE_PM_MASTER,
message & 0xff, TWL4030_PM_MASTER_PB_WORD_LSB);
}
/*----------------------------------------------------------------------*/
/*
* Support for adjustable-voltage LDOs uses a four bit (or less) voltage
* select field in its control register. We use tables indexed by VSEL
* to record voltages in milliVolts. (Accuracy is about three percent.)
*
* Note that VSEL values for VAUX2 changed in twl5030 and newer silicon;
* currently handled by listing two slightly different VAUX2 regulators,
* only one of which will be configured.
*
* VSEL values documented as "TI cannot support these values" are flagged
* in these tables as UNSUP() values; we normally won't assign them.
*
* VAUX3 at 3V is incorrectly listed in some TI manuals as unsupported.
* TI are revising the twl5030/tps659x0 specs to support that 3.0V setting.
*/
#ifdef CONFIG_TWL4030_ALLOW_UNSUPPORTED
#define UNSUP_MASK 0x0000
#else
#define UNSUP_MASK 0x8000
#endif
#define UNSUP(x) (UNSUP_MASK | (x))
#define IS_UNSUP(x) (UNSUP_MASK & (x))
#define LDO_MV(x) (~UNSUP_MASK & (x))
static const u16 VAUX1_VSEL_table[] = {
UNSUP(1500), UNSUP(1800), 2500, 2800,
3000, 3000, 3000, 3000,
};
static const u16 VAUX2_4030_VSEL_table[] = {
UNSUP(1000), UNSUP(1000), UNSUP(1200), 1300,
1500, 1800, UNSUP(1850), 2500,
UNSUP(2600), 2800, UNSUP(2850), UNSUP(3000),
UNSUP(3150), UNSUP(3150), UNSUP(3150), UNSUP(3150),
};
static const u16 VAUX2_VSEL_table[] = {
1700, 1700, 1900, 1300,
1500, 1800, 2000, 2500,
2100, 2800, 2200, 2300,
2400, 2400, 2400, 2400,
};
static const u16 VAUX3_VSEL_table[] = {
1500, 1800, 2500, 2800,
3000, 3000, 3000, 3000,
};
static const u16 VAUX4_VSEL_table[] = {
700, 1000, 1200, UNSUP(1300),
1500, 1800, UNSUP(1850), 2500,
UNSUP(2600), 2800, UNSUP(2850), UNSUP(3000),
UNSUP(3150), UNSUP(3150), UNSUP(3150), UNSUP(3150),
};
static const u16 VMMC1_VSEL_table[] = {
1850, 2850, 3000, 3150,
};
static const u16 VMMC2_VSEL_table[] = {
UNSUP(1000), UNSUP(1000), UNSUP(1200), UNSUP(1300),
UNSUP(1500), UNSUP(1800), 1850, UNSUP(2500),
2600, 2800, 2850, 3000,
3150, 3150, 3150, 3150,
};
static const u16 VPLL1_VSEL_table[] = {
1000, 1200, 1300, 1800,
UNSUP(2800), UNSUP(3000), UNSUP(3000), UNSUP(3000),
};
static const u16 VPLL2_VSEL_table[] = {
700, 1000, 1200, 1300,
UNSUP(1500), 1800, UNSUP(1850), UNSUP(2500),
UNSUP(2600), UNSUP(2800), UNSUP(2850), UNSUP(3000),
UNSUP(3150), UNSUP(3150), UNSUP(3150), UNSUP(3150),
};
static const u16 VSIM_VSEL_table[] = {
UNSUP(1000), UNSUP(1200), UNSUP(1300), 1800,
2800, 3000, 3000, 3000,
};
static const u16 VDAC_VSEL_table[] = {
1200, 1300, 1800, 1800,
};
static const u16 VDD1_VSEL_table[] = {
800, 1450,
};
static const u16 VDD2_VSEL_table[] = {
800, 1450, 1500,
};
static const u16 VIO_VSEL_table[] = {
1800, 1850,
};
static const u16 VINTANA2_VSEL_table[] = {
2500, 2750,
};
static int twl4030ldo_list_voltage(struct regulator_dev *rdev, unsigned index)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
int mV = info->table[index];
return IS_UNSUP(mV) ? 0 : (LDO_MV(mV) * 1000);
}
static int
twl4030ldo_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
unsigned *selector)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
int vsel;
for (vsel = 0; vsel < info->table_len; vsel++) {
int mV = info->table[vsel];
int uV;
if (IS_UNSUP(mV))
continue;
uV = LDO_MV(mV) * 1000;
/* REVISIT for VAUX2, first match may not be best/lowest */
/* use the first in-range value */
if (min_uV <= uV && uV <= max_uV) {
*selector = vsel;
return twlreg_write(info, TWL_MODULE_PM_RECEIVER,
VREG_VOLTAGE, vsel);
}
}
return -EDOM;
}
static int twl4030ldo_get_voltage(struct regulator_dev *rdev)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
int vsel = twlreg_read(info, TWL_MODULE_PM_RECEIVER,
VREG_VOLTAGE);
if (vsel < 0)
return vsel;
vsel &= info->table_len - 1;
return LDO_MV(info->table[vsel]) * 1000;
}
static struct regulator_ops twl4030ldo_ops = {
.list_voltage = twl4030ldo_list_voltage,
.set_voltage = twl4030ldo_set_voltage,
.get_voltage = twl4030ldo_get_voltage,
.enable = twlreg_enable,
.disable = twlreg_disable,
.is_enabled = twlreg_is_enabled,
.set_mode = twlreg_set_mode,
.get_status = twlreg_get_status,
};
static int twl6030ldo_list_voltage(struct regulator_dev *rdev, unsigned index)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
return ((info->min_mV + (index * 100)) * 1000);
}
static int
twl6030ldo_set_voltage(struct regulator_dev *rdev, int min_uV, int max_uV,
unsigned *selector)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
int vsel;
if ((min_uV/1000 < info->min_mV) || (max_uV/1000 > info->max_mV))
return -EDOM;
/*
* Use the below formula to calculate vsel
* mV = 1000mv + 100mv * (vsel - 1)
*/
vsel = (min_uV/1000 - 1000)/100 + 1;
*selector = vsel;
return twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_VOLTAGE, vsel);
}
static int twl6030ldo_get_voltage(struct regulator_dev *rdev)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
int vsel = twlreg_read(info, TWL_MODULE_PM_RECEIVER,
VREG_VOLTAGE);
if (vsel < 0)
return vsel;
/*
* Use the below formula to calculate vsel
* mV = 1000mv + 100mv * (vsel - 1)
*/
return (1000 + (100 * (vsel - 1))) * 1000;
}
static struct regulator_ops twl6030ldo_ops = {
.list_voltage = twl6030ldo_list_voltage,
.set_voltage = twl6030ldo_set_voltage,
.get_voltage = twl6030ldo_get_voltage,
.enable = twlreg_enable,
.disable = twlreg_disable,
.is_enabled = twlreg_is_enabled,
.set_mode = twlreg_set_mode,
.get_status = twlreg_get_status,
};
/*----------------------------------------------------------------------*/
/*
* Fixed voltage LDOs don't have a VSEL field to update.
*/
static int twlfixed_list_voltage(struct regulator_dev *rdev, unsigned index)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
return info->min_mV * 1000;
}
static int twlfixed_get_voltage(struct regulator_dev *rdev)
{
struct twlreg_info *info = rdev_get_drvdata(rdev);
return info->min_mV * 1000;
}
static struct regulator_ops twlfixed_ops = {
.list_voltage = twlfixed_list_voltage,
.get_voltage = twlfixed_get_voltage,
.enable = twlreg_enable,
.disable = twlreg_disable,
.is_enabled = twlreg_is_enabled,
.set_mode = twlreg_set_mode,
.get_status = twlreg_get_status,
};
static struct regulator_ops twl6030_fixed_resource = {
.enable = twlreg_enable,
.disable = twlreg_disable,
.is_enabled = twlreg_is_enabled,
.get_status = twlreg_get_status,
};
/*----------------------------------------------------------------------*/
#define TWL4030_FIXED_LDO(label, offset, mVolts, num, turnon_delay, \
remap_conf) \
TWL_FIXED_LDO(label, offset, mVolts, num, turnon_delay, \
remap_conf, TWL4030)
#define TWL6030_FIXED_LDO(label, offset, mVolts, num, turnon_delay, \
remap_conf) \
TWL_FIXED_LDO(label, offset, mVolts, num, turnon_delay, \
remap_conf, TWL6030)
#define TWL4030_ADJUSTABLE_LDO(label, offset, num, turnon_delay, remap_conf) { \
.base = offset, \
.id = num, \
.table_len = ARRAY_SIZE(label##_VSEL_table), \
.table = label##_VSEL_table, \
.delay = turnon_delay, \
.remap = remap_conf, \
.desc = { \
.name = #label, \
.id = TWL4030_REG_##label, \
.n_voltages = ARRAY_SIZE(label##_VSEL_table), \
.ops = &twl4030ldo_ops, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
}, \
}
#define TWL6030_ADJUSTABLE_LDO(label, offset, min_mVolts, max_mVolts, num, \
remap_conf) { \
.base = offset, \
.id = num, \
.min_mV = min_mVolts, \
.max_mV = max_mVolts, \
.remap = remap_conf, \
.desc = { \
.name = #label, \
.id = TWL6030_REG_##label, \
.n_voltages = (max_mVolts - min_mVolts)/100, \
.ops = &twl6030ldo_ops, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
}, \
}
#define TWL_FIXED_LDO(label, offset, mVolts, num, turnon_delay, remap_conf, \
family) { \
.base = offset, \
.id = num, \
.min_mV = mVolts, \
.delay = turnon_delay, \
.remap = remap_conf, \
.desc = { \
.name = #label, \
.id = family##_REG_##label, \
.n_voltages = 1, \
.ops = &twlfixed_ops, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
}, \
}
#define TWL6030_FIXED_RESOURCE(label, offset, num, turnon_delay, remap_conf) { \
.base = offset, \
.id = num, \
.delay = turnon_delay, \
.remap = remap_conf, \
.desc = { \
.name = #label, \
.id = TWL6030_REG_##label, \
.ops = &twl6030_fixed_resource, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
}, \
}
/*
* We list regulators here if systems need some level of
* software control over them after boot.
*/
static struct twlreg_info twl_regs[] = {
TWL4030_ADJUSTABLE_LDO(VAUX1, 0x17, 1, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VAUX2_4030, 0x1b, 2, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VAUX2, 0x1b, 2, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VAUX3, 0x1f, 3, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VAUX4, 0x23, 4, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VMMC1, 0x27, 5, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VMMC2, 0x2b, 6, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VPLL1, 0x2f, 7, 100, 0x00),
TWL4030_ADJUSTABLE_LDO(VPLL2, 0x33, 8, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VSIM, 0x37, 9, 100, 0x00),
TWL4030_ADJUSTABLE_LDO(VDAC, 0x3b, 10, 100, 0x08),
TWL4030_FIXED_LDO(VINTANA1, 0x3f, 1500, 11, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VINTANA2, 0x43, 12, 100, 0x08),
TWL4030_FIXED_LDO(VINTDIG, 0x47, 1500, 13, 100, 0x08),
TWL4030_ADJUSTABLE_LDO(VIO, 0x4b, 14, 1000, 0x08),
TWL4030_ADJUSTABLE_LDO(VDD1, 0x55, 15, 1000, 0x08),
TWL4030_ADJUSTABLE_LDO(VDD2, 0x63, 16, 1000, 0x08),
TWL4030_FIXED_LDO(VUSB1V5, 0x71, 1500, 17, 100, 0x08),
TWL4030_FIXED_LDO(VUSB1V8, 0x74, 1800, 18, 100, 0x08),
TWL4030_FIXED_LDO(VUSB3V1, 0x77, 3100, 19, 150, 0x08),
/* VUSBCP is managed *only* by the USB subchip */
/* 6030 REG with base as PMC Slave Misc : 0x0030 */
/* Turnon-delay and remap configuration values for 6030 are not
verified since the specification is not public */
TWL6030_ADJUSTABLE_LDO(VAUX1_6030, 0x54, 1000, 3300, 1, 0x21),
TWL6030_ADJUSTABLE_LDO(VAUX2_6030, 0x58, 1000, 3300, 2, 0x21),
TWL6030_ADJUSTABLE_LDO(VAUX3_6030, 0x5c, 1000, 3300, 3, 0x21),
TWL6030_ADJUSTABLE_LDO(VMMC, 0x68, 1000, 3300, 4, 0x21),
TWL6030_ADJUSTABLE_LDO(VPP, 0x6c, 1000, 3300, 5, 0x21),
TWL6030_ADJUSTABLE_LDO(VUSIM, 0x74, 1000, 3300, 7, 0x21),
TWL6030_FIXED_LDO(VANA, 0x50, 2100, 15, 0, 0x21),
TWL6030_FIXED_LDO(VCXIO, 0x60, 1800, 16, 0, 0x21),
TWL6030_FIXED_LDO(VDAC, 0x64, 1800, 17, 0, 0x21),
TWL6030_FIXED_LDO(VUSB, 0x70, 3300, 18, 0, 0x21),
TWL6030_FIXED_RESOURCE(CLK32KG, 0x8C, 48, 0, 0x21),
};
static int __devinit twlreg_probe(struct platform_device *pdev)
{
int i;
struct twlreg_info *info;
struct regulator_init_data *initdata;
struct regulation_constraints *c;
struct regulator_dev *rdev;
for (i = 0, info = NULL; i < ARRAY_SIZE(twl_regs); i++) {
if (twl_regs[i].desc.id != pdev->id)
continue;
info = twl_regs + i;
break;
}
if (!info)
return -ENODEV;
initdata = pdev->dev.platform_data;
if (!initdata)
return -EINVAL;
/* Constrain board-specific capabilities according to what
* this driver and the chip itself can actually do.
*/
c = &initdata->constraints;
c->valid_modes_mask &= REGULATOR_MODE_NORMAL | REGULATOR_MODE_STANDBY;
c->valid_ops_mask &= REGULATOR_CHANGE_VOLTAGE
| REGULATOR_CHANGE_MODE
| REGULATOR_CHANGE_STATUS;
switch (pdev->id) {
case TWL4030_REG_VIO:
case TWL4030_REG_VDD1:
case TWL4030_REG_VDD2:
case TWL4030_REG_VPLL1:
case TWL4030_REG_VINTANA1:
case TWL4030_REG_VINTANA2:
case TWL4030_REG_VINTDIG:
c->always_on = true;
break;
default:
break;
}
rdev = regulator_register(&info->desc, &pdev->dev, initdata, info);
if (IS_ERR(rdev)) {
dev_err(&pdev->dev, "can't register %s, %ld\n",
info->desc.name, PTR_ERR(rdev));
return PTR_ERR(rdev);
}
platform_set_drvdata(pdev, rdev);
twlreg_write(info, TWL_MODULE_PM_RECEIVER, VREG_REMAP,
info->remap);
/* NOTE: many regulators support short-circuit IRQs (presentable
* as REGULATOR_OVER_CURRENT notifications?) configured via:
* - SC_CONFIG
* - SC_DETECT1 (vintana2, vmmc1/2, vaux1/2/3/4)
* - SC_DETECT2 (vusb, vdac, vio, vdd1/2, vpll2)
* - IT_CONFIG
*/
return 0;
}
static int __devexit twlreg_remove(struct platform_device *pdev)
{
regulator_unregister(platform_get_drvdata(pdev));
return 0;
}
MODULE_ALIAS("platform:twl_reg");
static struct platform_driver twlreg_driver = {
.probe = twlreg_probe,
.remove = __devexit_p(twlreg_remove),
/* NOTE: short name, to work around driver model truncation of
* "twl_regulator.12" (and friends) to "twl_regulator.1".
*/
.driver.name = "twl_reg",
.driver.owner = THIS_MODULE,
};
static int __init twlreg_init(void)
{
return platform_driver_register(&twlreg_driver);
}
subsys_initcall(twlreg_init);
static void __exit twlreg_exit(void)
{
platform_driver_unregister(&twlreg_driver);
}
module_exit(twlreg_exit)
MODULE_DESCRIPTION("TWL regulator driver");
MODULE_LICENSE("GPL");