Initial Contribution

msm-2.6.38: tag AU_LINUX_ANDROID_GINGERBREAD.02.03.04.00.142

Signed-off-by: Bryan Huntsman <bryanh@codeaurora.org>
diff --git a/drivers/regulator/pmic8901-regulator.c b/drivers/regulator/pmic8901-regulator.c
new file mode 100644
index 0000000..5b4b907
--- /dev/null
+++ b/drivers/regulator/pmic8901-regulator.c
@@ -0,0 +1,1097 @@
+/* Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mfd/pmic8901.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/pmic8901-regulator.h>
+#include <mach/mpp.h>
+
+/* Regulator types */
+#define REGULATOR_TYPE_LDO		0
+#define REGULATOR_TYPE_SMPS		1
+#define REGULATOR_TYPE_VS		2
+#define REGULATOR_TYPE_MPP		3
+
+/* Bank select/write macros */
+#define REGULATOR_BANK_SEL(n)           ((n) << 4)
+#define REGULATOR_BANK_WRITE            0x80
+#define LDO_TEST_BANKS			7
+#define REGULATOR_BANK_MASK		0xF0
+
+/* Pin mask resource register programming */
+#define VREG_PMR_STATE_MASK		0x60
+#define VREG_PMR_STATE_HPM		0x60
+#define VREG_PMR_STATE_LPM		0x40
+#define VREG_PMR_STATE_OFF		0x20
+#define VREG_PMR_STATE_PIN_CTRL		0x20
+
+#define VREG_PMR_MODE_ACTION_MASK	0x10
+#define VREG_PMR_MODE_ACTION_SLEEP	0x10
+#define VREG_PMR_MODE_ACTION_OFF	0x00
+
+#define VREG_PMR_MODE_PIN_MASK		0x08
+#define VREG_PMR_MODE_PIN_MASKED	0x08
+
+#define VREG_PMR_CTRL_PIN2_MASK		0x04
+#define VREG_PMR_CTRL_PIN2_MASKED	0x04
+
+#define VREG_PMR_CTRL_PIN1_MASK		0x02
+#define VREG_PMR_CTRL_PIN1_MASKED	0x02
+
+#define VREG_PMR_CTRL_PIN0_MASK		0x01
+#define VREG_PMR_CTRL_PIN0_MASKED	0x01
+
+#define VREG_PMR_PIN_CTRL_ALL_MASK	0x1F
+#define VREG_PMR_PIN_CTRL_ALL_MASKED	0x1F
+
+#define REGULATOR_IS_EN(pmr_reg) \
+	((pmr_reg & VREG_PMR_STATE_MASK) == VREG_PMR_STATE_HPM || \
+	 (pmr_reg & VREG_PMR_STATE_MASK) == VREG_PMR_STATE_LPM)
+
+/* FTSMPS programming */
+
+/* CTRL register */
+#define SMPS_VCTRL_BAND_MASK		0xC0
+#define SMPS_VCTRL_BAND_OFF		0x00
+#define SMPS_VCTRL_BAND_1		0x40
+#define SMPS_VCTRL_BAND_2		0x80
+#define SMPS_VCTRL_BAND_3		0xC0
+#define SMPS_VCTRL_VPROG_MASK		0x3F
+
+#define SMPS_BAND_1_UV_MIN		350000
+#define SMPS_BAND_1_UV_MAX		650000
+#define SMPS_BAND_1_UV_STEP		6250
+
+#define SMPS_BAND_2_UV_MIN		700000
+#define SMPS_BAND_2_UV_MAX		1400000
+#define SMPS_BAND_2_UV_STEP		12500
+
+#define SMPS_BAND_3_UV_SETPOINT_MIN	1500000
+#define SMPS_BAND_3_UV_MIN		1400000
+#define SMPS_BAND_3_UV_MAX		3300000
+#define SMPS_BAND_3_UV_STEP		50000
+
+#define SMPS_UV_MIN			SMPS_BAND_1_UV_MIN
+#define SMPS_UV_MAX			SMPS_BAND_3_UV_MAX
+
+/* PWR_CNFG register */
+#define SMPS_PULL_DOWN_ENABLE_MASK	0x40
+#define SMPS_PULL_DOWN_ENABLE		0x40
+
+/* LDO programming */
+
+/* CTRL register */
+#define LDO_LOCAL_ENABLE_MASK		0x80
+#define LDO_LOCAL_ENABLE		0x80
+
+#define LDO_PULL_DOWN_ENABLE_MASK	0x40
+#define LDO_PULL_DOWN_ENABLE		0x40
+
+#define LDO_CTRL_VPROG_MASK		0x1F
+
+/* TEST register bank 2 */
+#define LDO_TEST_VPROG_UPDATE_MASK	0x08
+#define LDO_TEST_RANGE_SEL_MASK		0x04
+#define LDO_TEST_FINE_STEP_MASK		0x02
+#define LDO_TEST_FINE_STEP_SHIFT	1
+
+/* TEST register bank 4 */
+#define LDO_TEST_RANGE_EXT_MASK	0x01
+
+/* Allowable voltage ranges */
+#define PLDO_LOW_UV_MIN			750000
+#define PLDO_LOW_UV_MAX			1537500
+#define PLDO_LOW_FINE_STEP_UV		12500
+
+#define PLDO_NORM_UV_MIN		1500000
+#define PLDO_NORM_UV_MAX		3075000
+#define PLDO_NORM_FINE_STEP_UV		25000
+
+#define PLDO_HIGH_UV_MIN		1750000
+#define PLDO_HIGH_UV_MAX		4900000
+#define PLDO_HIGH_FINE_STEP_UV		50000
+
+#define NLDO_UV_MIN			750000
+#define NLDO_UV_MAX			1537500
+#define NLDO_FINE_STEP_UV		12500
+
+/* VS programming */
+
+/* CTRL register */
+#define VS_CTRL_ENABLE_MASK		0xC0
+#define VS_CTRL_DISABLE			0x00
+#define VS_CTRL_ENABLE			0x40
+#define VS_CTRL_USE_PMR			0xC0
+
+#define VS_PULL_DOWN_ENABLE_MASK	0x20
+#define VS_PULL_DOWN_ENABLE		0x20
+
+struct pm8901_vreg {
+	struct pm8901_vreg_pdata	*pdata;
+	struct regulator_dev		*rdev;
+	struct pm8901_chip		*chip;
+	int				hpm_min_load;
+	unsigned			pc_vote;
+	unsigned			optimum;
+	unsigned			mode_initialized;
+	u16				ctrl_addr;
+	u16				pmr_addr;
+	u16				test_addr;
+	u16				pfm_ctrl_addr;
+	u16				pwr_cnfg_addr;
+	u8				type;
+	u8				ctrl_reg;
+	u8				pmr_reg;
+	u8				test_reg[LDO_TEST_BANKS];
+	u8				pfm_ctrl_reg;
+	u8				pwr_cnfg_reg;
+	u8				is_nmos;
+	u8				mpp_id;
+	u8				state;
+};
+
+/*
+ * These are used to compensate for the PMIC 8901 v1 FTS regulators which
+ * output ~10% higher than the programmed set point.
+ */
+#define IS_PMIC_8901_V1(rev)		((rev) == PM_8901_REV_1p0 || \
+					 (rev) == PM_8901_REV_1p1)
+
+#define PMIC_8901_V1_SCALE(uV)		((((uV) - 62100) * 23) / 25)
+
+#define PMIC_8901_V1_SCALE_INV(uV)	(((uV) * 25) / 23 + 62100)
+
+/*
+ * Band 1 of PMIC 8901 SMPS regulators only supports set points with the 3 LSB's
+ * equal to 0.  This is accomplished in the macro by truncating the bits.
+ */
+#define PM8901_SMPS_BAND_1_COMPENSATE(vprog)	((vprog) & 0xF8)
+
+#define LDO(_id, _ctrl_addr, _pmr_addr, _test_addr, _is_nmos) \
+	[_id] = { \
+		.ctrl_addr = _ctrl_addr, \
+		.pmr_addr = _pmr_addr, \
+		.test_addr = _test_addr, \
+		.type = REGULATOR_TYPE_LDO, \
+		.is_nmos = _is_nmos, \
+		.hpm_min_load = PM8901_VREG_LDO_300_HPM_MIN_LOAD, \
+	}
+
+#define SMPS(_id, _ctrl_addr, _pmr_addr, _pfm_ctrl_addr, _pwr_cnfg_addr) \
+	[_id] = { \
+		.ctrl_addr = _ctrl_addr, \
+		.pmr_addr = _pmr_addr, \
+		.pfm_ctrl_addr = _pfm_ctrl_addr, \
+		.pwr_cnfg_addr = _pwr_cnfg_addr, \
+		.type = REGULATOR_TYPE_SMPS, \
+		.hpm_min_load = PM8901_VREG_FTSMPS_HPM_MIN_LOAD, \
+	}
+
+#define VS(_id, _ctrl_addr, _pmr_addr) \
+	[_id] = { \
+		.ctrl_addr = _ctrl_addr, \
+		.pmr_addr = _pmr_addr, \
+		.type = REGULATOR_TYPE_VS, \
+	}
+
+#define MPP(_id, _mpp_id) \
+	[_id] = { \
+		.mpp_id = _mpp_id, \
+		.type = REGULATOR_TYPE_MPP, \
+	}
+
+static struct pm8901_vreg pm8901_vreg[] = {
+	/*  id                 ctrl   pmr    tst    n/p */
+	LDO(PM8901_VREG_ID_L0, 0x02F, 0x0AB, 0x030, 1),
+	LDO(PM8901_VREG_ID_L1, 0x031, 0x0AC, 0x032, 0),
+	LDO(PM8901_VREG_ID_L2, 0x033, 0x0AD, 0x034, 0),
+	LDO(PM8901_VREG_ID_L3, 0x035, 0x0AE, 0x036, 0),
+	LDO(PM8901_VREG_ID_L4, 0x037, 0x0AF, 0x038, 0),
+	LDO(PM8901_VREG_ID_L5, 0x039, 0x0B0, 0x03A, 0),
+	LDO(PM8901_VREG_ID_L6, 0x03B, 0x0B1, 0x03C, 0),
+
+	/*   id                 ctrl   pmr    pfm    pwr */
+	SMPS(PM8901_VREG_ID_S0, 0x05B, 0x0A6, 0x05C, 0x0E3),
+	SMPS(PM8901_VREG_ID_S1, 0x06A, 0x0A7, 0x06B, 0x0EC),
+	SMPS(PM8901_VREG_ID_S2, 0x079, 0x0A8, 0x07A, 0x0F1),
+	SMPS(PM8901_VREG_ID_S3, 0x088, 0x0A9, 0x089, 0x0F6),
+	SMPS(PM8901_VREG_ID_S4, 0x097, 0x0AA, 0x098, 0x0FB),
+
+	/* id			  MPP ID */
+	MPP(PM8901_VREG_ID_MPP0,    0),
+
+	/* id                       ctrl   pmr */
+	VS(PM8901_VREG_ID_LVS0,     0x046, 0x0B2),
+	VS(PM8901_VREG_ID_LVS1,     0x048, 0x0B3),
+	VS(PM8901_VREG_ID_LVS2,     0x04A, 0x0B4),
+	VS(PM8901_VREG_ID_LVS3,     0x04C, 0x0B5),
+	VS(PM8901_VREG_ID_MVS0,     0x052, 0x0B6),
+	VS(PM8901_VREG_ID_USB_OTG,  0x055, 0x0B7),
+	VS(PM8901_VREG_ID_HDMI_MVS, 0x058, 0x0B8),
+};
+
+static void print_write_error(struct pm8901_vreg *vreg, int rc,
+				const char *func);
+
+static int pm8901_vreg_write(struct pm8901_chip *chip,
+		u16 addr, u8 val, u8 mask, u8 *reg_save)
+{
+	int rc = 0;
+	u8 reg;
+
+	reg = (*reg_save & ~mask) | (val & mask);
+	if (reg != *reg_save)
+		rc = pm8901_write(chip, addr, &reg, 1);
+	if (!rc)
+		*reg_save = reg;
+	return rc;
+}
+
+/* Set pin control bits based on new mode. */
+static int pm8901_vreg_select_pin_ctrl(struct pm8901_vreg *vreg, u8 *pmr_reg)
+{
+	*pmr_reg |= VREG_PMR_PIN_CTRL_ALL_MASKED;
+
+	if ((*pmr_reg & VREG_PMR_STATE_MASK) == VREG_PMR_STATE_PIN_CTRL) {
+		if (vreg->pdata->pin_fn == PM8901_VREG_PIN_FN_MODE)
+			*pmr_reg = (*pmr_reg & ~VREG_PMR_STATE_MASK)
+				   | VREG_PMR_STATE_LPM;
+		if (vreg->pdata->pin_ctrl & PM8901_VREG_PIN_CTRL_A0)
+			*pmr_reg &= ~VREG_PMR_CTRL_PIN0_MASKED;
+		if (vreg->pdata->pin_ctrl & PM8901_VREG_PIN_CTRL_A1)
+			*pmr_reg &= ~VREG_PMR_CTRL_PIN1_MASKED;
+		if (vreg->pdata->pin_ctrl & PM8901_VREG_PIN_CTRL_D0)
+			*pmr_reg &= ~VREG_PMR_CTRL_PIN2_MASKED;
+	}
+
+	return 0;
+}
+
+static int pm8901_vreg_enable(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	u8 val = VREG_PMR_STATE_HPM;
+	int rc;
+
+	if (!vreg->mode_initialized && vreg->pc_vote)
+		val = VREG_PMR_STATE_PIN_CTRL;
+	else if (vreg->optimum == REGULATOR_MODE_FAST)
+		val = VREG_PMR_STATE_HPM;
+	else if (vreg->pc_vote)
+		val = VREG_PMR_STATE_PIN_CTRL;
+	else if (vreg->optimum == REGULATOR_MODE_STANDBY)
+		val = VREG_PMR_STATE_LPM;
+
+	pm8901_vreg_select_pin_ctrl(vreg, &val);
+
+	rc = pm8901_vreg_write(chip, vreg->pmr_addr,
+			val,
+			VREG_PMR_STATE_MASK | VREG_PMR_PIN_CTRL_ALL_MASK,
+			&vreg->pmr_reg);
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	return rc;
+}
+
+static int pm8901_vreg_disable(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	int rc;
+
+	rc = pm8901_vreg_write(chip, vreg->pmr_addr,
+			VREG_PMR_STATE_OFF | VREG_PMR_PIN_CTRL_ALL_MASKED,
+			VREG_PMR_STATE_MASK | VREG_PMR_PIN_CTRL_ALL_MASK,
+			&vreg->pmr_reg);
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	return rc;
+}
+
+/*
+ * Cases that count as enabled:
+ *
+ * 1. PMR register has mode == HPM or LPM.
+ * 2. Any pin control bits are unmasked.
+ * 3. The regulator is an LDO and its local enable bit is set.
+ */
+static int _pm8901_vreg_is_enabled(struct pm8901_vreg *vreg)
+{
+	if ((vreg->type == REGULATOR_TYPE_LDO)
+	    && (vreg->ctrl_reg & LDO_LOCAL_ENABLE_MASK))
+		return 1;
+	else if (vreg->type == REGULATOR_TYPE_VS) {
+		if ((vreg->ctrl_reg & VS_CTRL_ENABLE_MASK) == VS_CTRL_ENABLE)
+			return 1;
+		else if ((vreg->ctrl_reg & VS_CTRL_ENABLE_MASK)
+			 == VS_CTRL_DISABLE)
+			return 0;
+	}
+
+	return REGULATOR_IS_EN(vreg->pmr_reg)
+		|| ((vreg->pmr_reg & VREG_PMR_PIN_CTRL_ALL_MASK)
+		   != VREG_PMR_PIN_CTRL_ALL_MASKED);
+}
+
+static int pm8901_vreg_is_enabled(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+
+	return _pm8901_vreg_is_enabled(vreg);
+}
+
+static int pm8901_ldo_disable(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	int rc;
+
+	/* Disassert local enable bit in CTRL register. */
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr, 0, LDO_LOCAL_ENABLE_MASK,
+			&vreg->ctrl_reg);
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	/* Disassert enable bit in PMR register. */
+	rc = pm8901_vreg_disable(dev);
+
+	return rc;
+}
+
+static int pm8901_pldo_set_voltage(struct pm8901_chip *chip,
+		struct pm8901_vreg *vreg, int uV)
+{
+	int vmin, rc = 0;
+	unsigned vprog, fine_step;
+	u8 range_ext, range_sel, fine_step_reg;
+
+	if (uV < PLDO_LOW_UV_MIN || uV > PLDO_HIGH_UV_MAX)
+		return -EINVAL;
+
+	if (uV < PLDO_LOW_UV_MAX + PLDO_LOW_FINE_STEP_UV) {
+		vmin = PLDO_LOW_UV_MIN;
+		fine_step = PLDO_LOW_FINE_STEP_UV;
+		range_ext = 0;
+		range_sel = LDO_TEST_RANGE_SEL_MASK;
+	} else if (uV < PLDO_NORM_UV_MAX + PLDO_NORM_FINE_STEP_UV) {
+		vmin = PLDO_NORM_UV_MIN;
+		fine_step = PLDO_NORM_FINE_STEP_UV;
+		range_ext = 0;
+		range_sel = 0;
+	} else {
+		vmin = PLDO_HIGH_UV_MIN;
+		fine_step = PLDO_HIGH_FINE_STEP_UV;
+		range_ext = LDO_TEST_RANGE_EXT_MASK;
+		range_sel = 0;
+	}
+
+	vprog = (uV - vmin) / fine_step;
+	fine_step_reg = (vprog & 1) << LDO_TEST_FINE_STEP_SHIFT;
+	vprog >>= 1;
+
+	/*
+	 * Disable program voltage update if range extension, range select,
+	 * or fine step have changed and the regulator is enabled.
+	 */
+	if (_pm8901_vreg_is_enabled(vreg) &&
+		(((range_ext ^ vreg->test_reg[4]) & LDO_TEST_RANGE_EXT_MASK)
+		|| ((range_sel ^ vreg->test_reg[2]) & LDO_TEST_RANGE_SEL_MASK)
+		|| ((fine_step_reg ^ vreg->test_reg[2])
+			& LDO_TEST_FINE_STEP_MASK))) {
+		rc = pm8901_vreg_write(chip, vreg->test_addr,
+			REGULATOR_BANK_SEL(2) | REGULATOR_BANK_WRITE,
+			REGULATOR_BANK_MASK | LDO_TEST_VPROG_UPDATE_MASK,
+			&vreg->test_reg[2]);
+		if (rc)
+			goto bail;
+	}
+
+	/* Write new voltage. */
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr, vprog,
+				LDO_CTRL_VPROG_MASK, &vreg->ctrl_reg);
+	if (rc)
+		goto bail;
+
+	/* Write range extension. */
+	rc = pm8901_vreg_write(chip, vreg->test_addr,
+			range_ext | REGULATOR_BANK_SEL(4)
+			 | REGULATOR_BANK_WRITE,
+			LDO_TEST_RANGE_EXT_MASK | REGULATOR_BANK_MASK,
+			&vreg->test_reg[4]);
+	if (rc)
+		goto bail;
+
+	/* Write fine step, range select and program voltage update. */
+	rc = pm8901_vreg_write(chip, vreg->test_addr,
+			fine_step_reg | range_sel | REGULATOR_BANK_SEL(2)
+			 | REGULATOR_BANK_WRITE | LDO_TEST_VPROG_UPDATE_MASK,
+			LDO_TEST_FINE_STEP_MASK | LDO_TEST_RANGE_SEL_MASK
+			 | REGULATOR_BANK_MASK | LDO_TEST_VPROG_UPDATE_MASK,
+			&vreg->test_reg[2]);
+bail:
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	return rc;
+}
+
+static int pm8901_nldo_set_voltage(struct pm8901_chip *chip,
+		struct pm8901_vreg *vreg, int uV)
+{
+	unsigned vprog, fine_step_reg;
+	int rc;
+
+	if (uV < NLDO_UV_MIN || uV > NLDO_UV_MAX)
+		return -EINVAL;
+
+	vprog = (uV - NLDO_UV_MIN) / NLDO_FINE_STEP_UV;
+	fine_step_reg = (vprog & 1) << LDO_TEST_FINE_STEP_SHIFT;
+	vprog >>= 1;
+
+	/* Write new voltage. */
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr, vprog,
+				LDO_CTRL_VPROG_MASK, &vreg->ctrl_reg);
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	/* Write fine step. */
+	rc = pm8901_vreg_write(chip, vreg->test_addr,
+			fine_step_reg | REGULATOR_BANK_SEL(2)
+			 | REGULATOR_BANK_WRITE | LDO_TEST_VPROG_UPDATE_MASK,
+			LDO_TEST_FINE_STEP_MASK | REGULATOR_BANK_MASK
+			 | LDO_TEST_VPROG_UPDATE_MASK,
+		       &vreg->test_reg[2]);
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	return rc;
+}
+
+static int pm8901_ldo_set_voltage(struct regulator_dev *dev,
+		int min_uV, int max_uV, unsigned *selector)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+
+	if (vreg->is_nmos)
+		return pm8901_nldo_set_voltage(chip, vreg, min_uV);
+	else
+		return pm8901_pldo_set_voltage(chip, vreg, min_uV);
+}
+
+static int pm8901_pldo_get_voltage(struct pm8901_vreg *vreg)
+{
+	int vmin, fine_step;
+	u8 range_ext, range_sel, vprog, fine_step_reg;
+
+	fine_step_reg = vreg->test_reg[2] & LDO_TEST_FINE_STEP_MASK;
+	range_sel = vreg->test_reg[2] & LDO_TEST_RANGE_SEL_MASK;
+	range_ext = vreg->test_reg[4] & LDO_TEST_RANGE_EXT_MASK;
+	vprog = vreg->ctrl_reg & LDO_CTRL_VPROG_MASK;
+
+	vprog = (vprog << 1) | (fine_step_reg >> LDO_TEST_FINE_STEP_SHIFT);
+
+	if (range_sel) {
+		/* low range mode */
+		fine_step = PLDO_LOW_FINE_STEP_UV;
+		vmin = PLDO_LOW_UV_MIN;
+	} else if (!range_ext) {
+		/* normal mode */
+		fine_step = PLDO_NORM_FINE_STEP_UV;
+		vmin = PLDO_NORM_UV_MIN;
+	} else {
+		/* high range mode */
+		fine_step = PLDO_HIGH_FINE_STEP_UV;
+		vmin = PLDO_HIGH_UV_MIN;
+	}
+
+	return fine_step * vprog + vmin;
+}
+
+static int pm8901_nldo_get_voltage(struct pm8901_vreg *vreg)
+{
+	u8 vprog, fine_step_reg;
+
+	fine_step_reg = vreg->test_reg[2] & LDO_TEST_FINE_STEP_MASK;
+	vprog = vreg->ctrl_reg & LDO_CTRL_VPROG_MASK;
+
+	vprog = (vprog << 1) | (fine_step_reg >> LDO_TEST_FINE_STEP_SHIFT);
+
+	return NLDO_FINE_STEP_UV * vprog + NLDO_UV_MIN;
+}
+
+static int pm8901_ldo_get_voltage(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+
+	if (vreg->is_nmos)
+		return pm8901_nldo_get_voltage(vreg);
+	else
+		return pm8901_pldo_get_voltage(vreg);
+}
+
+/*
+ * Optimum mode programming:
+ * REGULATOR_MODE_FAST: Go to HPM (highest priority)
+ * REGULATOR_MODE_STANDBY: Go to pin ctrl mode if there are any pin ctrl
+ * votes, else go to LPM
+ *
+ * Pin ctrl mode voting via regulator set_mode:
+ * REGULATOR_MODE_IDLE: Go to pin ctrl mode if the optimum mode is LPM, else
+ * go to HPM
+ * REGULATOR_MODE_NORMAL: Go to LPM if it is the optimum mode, else go to HPM
+ */
+static int pm8901_vreg_set_mode(struct regulator_dev *dev, unsigned int mode)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	unsigned optimum = vreg->optimum;
+	unsigned pc_vote = vreg->pc_vote;
+	unsigned mode_initialized = vreg->mode_initialized;
+	u8 val = 0;
+	int rc = 0;
+
+	/* Determine new mode to go into. */
+	switch (mode) {
+	case REGULATOR_MODE_FAST:
+		val = VREG_PMR_STATE_HPM;
+		optimum = mode;
+		mode_initialized = 1;
+		break;
+
+	case REGULATOR_MODE_STANDBY:
+		if (pc_vote)
+			val = VREG_PMR_STATE_PIN_CTRL;
+		else
+			val = VREG_PMR_STATE_LPM;
+		optimum = mode;
+		mode_initialized = 1;
+		break;
+
+	case REGULATOR_MODE_IDLE:
+		if (pc_vote++)
+			goto done; /* already taken care of */
+
+		if (mode_initialized && optimum == REGULATOR_MODE_FAST)
+			val = VREG_PMR_STATE_HPM;
+		else
+			val = VREG_PMR_STATE_PIN_CTRL;
+		break;
+
+	case REGULATOR_MODE_NORMAL:
+		if (pc_vote && --pc_vote)
+			goto done; /* already taken care of */
+
+		if (optimum == REGULATOR_MODE_STANDBY)
+			val = VREG_PMR_STATE_LPM;
+		else
+			val = VREG_PMR_STATE_HPM;
+		break;
+
+	default:
+		pr_err("%s: unknown mode, mode=%u\n", __func__, mode);
+		return -EINVAL;
+	}
+
+	/* Set pin control bits based on new mode. */
+	pm8901_vreg_select_pin_ctrl(vreg, &val);
+
+	/* Only apply mode setting to hardware if currently enabled. */
+	if (pm8901_vreg_is_enabled(dev))
+		rc = pm8901_vreg_write(chip, vreg->pmr_addr, val,
+			       VREG_PMR_STATE_MASK | VREG_PMR_PIN_CTRL_ALL_MASK,
+			       &vreg->pmr_reg);
+
+	if (rc) {
+		print_write_error(vreg, rc, __func__);
+		return rc;
+	}
+
+done:
+	vreg->mode_initialized = mode_initialized;
+	vreg->optimum = optimum;
+	vreg->pc_vote = pc_vote;
+
+	return 0;
+}
+
+static unsigned int pm8901_vreg_get_mode(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	int pin_mask = VREG_PMR_CTRL_PIN0_MASK | VREG_PMR_CTRL_PIN1_MASK
+			| VREG_PMR_CTRL_PIN2_MASK;
+
+	if (!vreg->mode_initialized && vreg->pc_vote)
+		return REGULATOR_MODE_IDLE;
+	else if (((vreg->pmr_reg & VREG_PMR_STATE_MASK) == VREG_PMR_STATE_OFF)
+		 && ((vreg->pmr_reg & pin_mask) != pin_mask))
+		return REGULATOR_MODE_IDLE;
+	else if (((vreg->pmr_reg & VREG_PMR_STATE_MASK) == VREG_PMR_STATE_LPM)
+		 && ((vreg->pmr_reg & pin_mask) != pin_mask))
+		return REGULATOR_MODE_IDLE;
+	else if (vreg->optimum == REGULATOR_MODE_FAST)
+		return REGULATOR_MODE_FAST;
+	else if (vreg->pc_vote)
+		return REGULATOR_MODE_IDLE;
+	else if (vreg->optimum == REGULATOR_MODE_STANDBY)
+		return REGULATOR_MODE_STANDBY;
+	return REGULATOR_MODE_FAST;
+}
+
+unsigned int pm8901_vreg_get_optimum_mode(struct regulator_dev *dev,
+		int input_uV, int output_uV, int load_uA)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+
+	if (load_uA <= 0) {
+		/*
+		 * pm8901_vreg_get_optimum_mode is being called before consumers
+		 * have specified their load currents via
+		 * regulator_set_optimum_mode. Return whatever the existing mode
+		 * is.
+		 */
+		return pm8901_vreg_get_mode(dev);
+	}
+
+	if (load_uA >= vreg->hpm_min_load)
+		return REGULATOR_MODE_FAST;
+	return REGULATOR_MODE_STANDBY;
+}
+
+static int pm8901_smps_set_voltage(struct regulator_dev *dev,
+		int min_uV, int max_uV, unsigned *selector)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	int rc;
+	u8 val, band;
+
+	if (IS_PMIC_8901_V1(pm8901_rev(chip)))
+		min_uV = PMIC_8901_V1_SCALE(min_uV);
+
+	if (min_uV < SMPS_BAND_1_UV_MIN || min_uV > SMPS_BAND_3_UV_MAX)
+		return -EINVAL;
+
+	/* Round down for set points in the gaps between bands. */
+	if (min_uV > SMPS_BAND_1_UV_MAX && min_uV < SMPS_BAND_2_UV_MIN)
+		min_uV = SMPS_BAND_1_UV_MAX;
+	else if (min_uV > SMPS_BAND_2_UV_MAX
+			&& min_uV < SMPS_BAND_3_UV_SETPOINT_MIN)
+		min_uV = SMPS_BAND_2_UV_MAX;
+
+	if (min_uV < SMPS_BAND_2_UV_MIN) {
+		val = ((min_uV - SMPS_BAND_1_UV_MIN) / SMPS_BAND_1_UV_STEP);
+		val = PM8901_SMPS_BAND_1_COMPENSATE(val);
+		band = SMPS_VCTRL_BAND_1;
+	} else if (min_uV < SMPS_BAND_3_UV_SETPOINT_MIN) {
+		val = ((min_uV - SMPS_BAND_2_UV_MIN) / SMPS_BAND_2_UV_STEP);
+		band = SMPS_VCTRL_BAND_2;
+	} else {
+		val = ((min_uV - SMPS_BAND_3_UV_MIN) / SMPS_BAND_3_UV_STEP);
+		band = SMPS_VCTRL_BAND_3;
+	}
+
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr, band | val,
+			SMPS_VCTRL_BAND_MASK | SMPS_VCTRL_VPROG_MASK,
+			&vreg->ctrl_reg);
+	if (rc)
+		goto bail;
+
+	rc = pm8901_vreg_write(chip, vreg->pfm_ctrl_addr, band | val,
+			SMPS_VCTRL_BAND_MASK | SMPS_VCTRL_VPROG_MASK,
+			&vreg->pfm_ctrl_reg);
+bail:
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	return rc;
+}
+
+static int pm8901_smps_get_voltage(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	u8 vprog, band;
+	int ret = 0;
+
+	if ((vreg->pmr_reg & VREG_PMR_STATE_MASK) == VREG_PMR_STATE_LPM) {
+		vprog = vreg->pfm_ctrl_reg & SMPS_VCTRL_VPROG_MASK;
+		band = vreg->pfm_ctrl_reg & SMPS_VCTRL_BAND_MASK;
+	} else {
+		vprog = vreg->ctrl_reg & SMPS_VCTRL_VPROG_MASK;
+		band = vreg->ctrl_reg & SMPS_VCTRL_BAND_MASK;
+	}
+
+	if (band == SMPS_VCTRL_BAND_1)
+		ret = vprog * SMPS_BAND_1_UV_STEP + SMPS_BAND_1_UV_MIN;
+	else if (band == SMPS_VCTRL_BAND_2)
+		ret = vprog * SMPS_BAND_2_UV_STEP + SMPS_BAND_2_UV_MIN;
+	else
+		ret = vprog * SMPS_BAND_3_UV_STEP + SMPS_BAND_3_UV_MIN;
+
+	if (IS_PMIC_8901_V1(pm8901_rev(chip)))
+		ret = PMIC_8901_V1_SCALE_INV(ret);
+
+	return ret;
+}
+
+static int pm8901_vs_enable(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	int rc;
+
+	/* Assert enable bit in PMR register. */
+	rc = pm8901_vreg_enable(dev);
+
+	/* Make sure that switch is controlled via PMR register */
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr, VS_CTRL_USE_PMR,
+			VS_CTRL_ENABLE_MASK, &vreg->ctrl_reg);
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	return rc;
+}
+
+static int pm8901_vs_disable(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	struct pm8901_chip *chip = vreg->chip;
+	int rc;
+
+	/* Disassert enable bit in PMR register. */
+	rc = pm8901_vreg_disable(dev);
+
+	/* Make sure that switch is controlled via PMR register */
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr, VS_CTRL_USE_PMR,
+			VS_CTRL_ENABLE_MASK, &vreg->ctrl_reg);
+	if (rc)
+		print_write_error(vreg, rc, __func__);
+
+	return rc;
+}
+
+static int pm8901_mpp_enable(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	int out_val;
+	int rc;
+
+	out_val = (vreg->pdata->active_high
+		   ? PM_MPP_DOUT_CTL_HIGH : PM_MPP_DOUT_CTL_LOW);
+
+	rc = pm8901_mpp_config(vreg->mpp_id, PM_MPP_TYPE_D_OUTPUT,
+			PM8901_MPP_DIG_LEVEL_VPH, out_val);
+
+	if (rc)
+		pr_err("%s: pm8901_mpp_config failed, rc=%d\n", __func__, rc);
+	else
+		vreg->state = 1;
+
+	return rc;
+}
+
+static int pm8901_mpp_disable(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	int out_val;
+	int rc;
+
+	out_val = (vreg->pdata->active_high
+		   ? PM_MPP_DOUT_CTL_LOW : PM_MPP_DOUT_CTL_HIGH);
+
+	rc = pm8901_mpp_config(vreg->mpp_id, PM_MPP_TYPE_D_OUTPUT,
+			PM8901_MPP_DIG_LEVEL_VPH, out_val);
+
+	if (rc)
+		pr_err("%s: pm8901_mpp_config failed, rc=%d\n", __func__, rc);
+	else
+		vreg->state = 0;
+
+	return rc;
+}
+
+static int pm8901_mpp_is_enabled(struct regulator_dev *dev)
+{
+	struct pm8901_vreg *vreg = rdev_get_drvdata(dev);
+	return vreg->state;
+}
+
+static struct regulator_ops pm8901_ldo_ops = {
+	.enable = pm8901_vreg_enable,
+	.disable = pm8901_ldo_disable,
+	.is_enabled = pm8901_vreg_is_enabled,
+	.set_voltage = pm8901_ldo_set_voltage,
+	.get_voltage = pm8901_ldo_get_voltage,
+	.set_mode = pm8901_vreg_set_mode,
+	.get_mode = pm8901_vreg_get_mode,
+	.get_optimum_mode = pm8901_vreg_get_optimum_mode,
+};
+
+static struct regulator_ops pm8901_smps_ops = {
+	.enable = pm8901_vreg_enable,
+	.disable = pm8901_vreg_disable,
+	.is_enabled = pm8901_vreg_is_enabled,
+	.set_voltage = pm8901_smps_set_voltage,
+	.get_voltage = pm8901_smps_get_voltage,
+	.set_mode = pm8901_vreg_set_mode,
+	.get_mode = pm8901_vreg_get_mode,
+	.get_optimum_mode = pm8901_vreg_get_optimum_mode,
+};
+
+static struct regulator_ops pm8901_vs_ops = {
+	.enable = pm8901_vs_enable,
+	.disable = pm8901_vs_disable,
+	.is_enabled = pm8901_vreg_is_enabled,
+	.set_mode = pm8901_vreg_set_mode,
+	.get_mode = pm8901_vreg_get_mode,
+};
+
+static struct regulator_ops pm8901_mpp_ops = {
+	.enable = pm8901_mpp_enable,
+	.disable = pm8901_mpp_disable,
+	.is_enabled = pm8901_mpp_is_enabled,
+};
+
+#define VREG_DESCRIP(_id, _name, _ops) \
+	[_id] = { \
+		.name = _name, \
+		.id = _id, \
+		.ops = _ops, \
+		.type = REGULATOR_VOLTAGE, \
+		.owner = THIS_MODULE, \
+	}
+
+static struct regulator_desc pm8901_vreg_descrip[] = {
+	VREG_DESCRIP(PM8901_VREG_ID_L0, "8901_l0", &pm8901_ldo_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_L1, "8901_l1", &pm8901_ldo_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_L2, "8901_l2", &pm8901_ldo_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_L3, "8901_l3", &pm8901_ldo_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_L4, "8901_l4", &pm8901_ldo_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_L5, "8901_l5", &pm8901_ldo_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_L6, "8901_l6", &pm8901_ldo_ops),
+
+	VREG_DESCRIP(PM8901_VREG_ID_S0, "8901_s0", &pm8901_smps_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_S1, "8901_s1", &pm8901_smps_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_S2, "8901_s2", &pm8901_smps_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_S3, "8901_s3", &pm8901_smps_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_S4, "8901_s4", &pm8901_smps_ops),
+
+	VREG_DESCRIP(PM8901_VREG_ID_MPP0,     "8901_mpp0",     &pm8901_mpp_ops),
+
+	VREG_DESCRIP(PM8901_VREG_ID_LVS0,     "8901_lvs0",     &pm8901_vs_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_LVS1,     "8901_lvs1",     &pm8901_vs_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_LVS2,     "8901_lvs2",     &pm8901_vs_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_LVS3,     "8901_lvs3",     &pm8901_vs_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_MVS0,     "8901_mvs0",     &pm8901_vs_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_USB_OTG,  "8901_usb_otg",  &pm8901_vs_ops),
+	VREG_DESCRIP(PM8901_VREG_ID_HDMI_MVS, "8901_hdmi_mvs", &pm8901_vs_ops),
+};
+
+static int pm8901_init_ldo(struct pm8901_chip *chip, struct pm8901_vreg *vreg)
+{
+	int rc = 0, i;
+	u8 bank;
+
+	/* Store current regulator register values. */
+	for (i = 0; i < LDO_TEST_BANKS; i++) {
+		bank = REGULATOR_BANK_SEL(i);
+		rc = pm8901_write(chip, vreg->test_addr, &bank, 1);
+		if (rc)
+			goto bail;
+
+		rc = pm8901_read(chip, vreg->test_addr, &vreg->test_reg[i], 1);
+		if (rc)
+			goto bail;
+
+		vreg->test_reg[i] |= REGULATOR_BANK_WRITE;
+	}
+
+	/* Set pull down enable based on platform data. */
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr,
+		     (vreg->pdata->pull_down_enable ? LDO_PULL_DOWN_ENABLE : 0),
+		     LDO_PULL_DOWN_ENABLE_MASK, &vreg->ctrl_reg);
+bail:
+	return rc;
+}
+
+static int pm8901_init_smps(struct pm8901_chip *chip, struct pm8901_vreg *vreg)
+{
+	int rc;
+
+	/* Store current regulator register values. */
+	rc = pm8901_read(chip, vreg->pfm_ctrl_addr,
+			 &vreg->pfm_ctrl_reg, 1);
+	if (rc)
+		goto bail;
+
+	rc = pm8901_read(chip, vreg->pwr_cnfg_addr,
+			 &vreg->pwr_cnfg_reg, 1);
+	if (rc)
+		goto bail;
+
+	/* Set pull down enable based on platform data. */
+	rc = pm8901_vreg_write(chip, vreg->pwr_cnfg_addr,
+		    (vreg->pdata->pull_down_enable ? SMPS_PULL_DOWN_ENABLE : 0),
+		    SMPS_PULL_DOWN_ENABLE_MASK, &vreg->pwr_cnfg_reg);
+
+bail:
+	return rc;
+}
+
+static int pm8901_init_vs(struct pm8901_chip *chip, struct pm8901_vreg *vreg)
+{
+	int rc = 0;
+
+	/* Set pull down enable based on platform data. */
+	rc = pm8901_vreg_write(chip, vreg->ctrl_addr,
+		      (vreg->pdata->pull_down_enable ? VS_PULL_DOWN_ENABLE : 0),
+		      VS_PULL_DOWN_ENABLE_MASK, &vreg->ctrl_reg);
+
+	return rc;
+}
+
+static int pm8901_init_regulator(struct pm8901_chip *chip,
+		struct pm8901_vreg *vreg)
+{
+	int rc;
+
+	/* Store current regulator register values. */
+	if (vreg->type != REGULATOR_TYPE_MPP) {
+		rc = pm8901_read(chip, vreg->ctrl_addr, &vreg->ctrl_reg, 1);
+		if (rc)
+			goto bail;
+
+		rc = pm8901_read(chip, vreg->pmr_addr, &vreg->pmr_reg, 1);
+		if (rc)
+			goto bail;
+	}
+
+	/* Set initial mode based on hardware state. */
+	if ((vreg->pmr_reg & VREG_PMR_STATE_MASK) == VREG_PMR_STATE_LPM)
+		vreg->optimum = REGULATOR_MODE_STANDBY;
+	else
+		vreg->optimum = REGULATOR_MODE_FAST;
+
+	vreg->mode_initialized = 0;
+
+	if (vreg->type == REGULATOR_TYPE_LDO)
+		rc = pm8901_init_ldo(chip, vreg);
+	else if (vreg->type == REGULATOR_TYPE_SMPS)
+		rc = pm8901_init_smps(chip, vreg);
+	else if (vreg->type == REGULATOR_TYPE_VS)
+		rc = pm8901_init_vs(chip, vreg);
+bail:
+	if (rc)
+		pr_err("%s: pm8901_read/write failed; initial register states "
+			"unknown, rc=%d\n", __func__, rc);
+
+	return rc;
+}
+
+static int __devinit pm8901_vreg_probe(struct platform_device *pdev)
+{
+	struct regulator_desc *rdesc;
+	struct pm8901_chip *chip;
+	struct pm8901_vreg *vreg;
+	const char *reg_name = NULL;
+	int rc = 0;
+
+	if (pdev == NULL)
+		return -EINVAL;
+
+	if (pdev->id >= 0 && pdev->id < PM8901_VREG_MAX) {
+		chip = dev_get_drvdata(pdev->dev.parent);
+		rdesc = &pm8901_vreg_descrip[pdev->id];
+		vreg = &pm8901_vreg[pdev->id];
+		vreg->pdata = pdev->dev.platform_data;
+		vreg->chip = chip;
+		reg_name = pm8901_vreg_descrip[pdev->id].name;
+
+		rc = pm8901_init_regulator(chip, vreg);
+		if (rc)
+			goto bail;
+
+		/* Disallow idle and normal modes if pin control isn't set. */
+		if (vreg->pdata->pin_ctrl == 0)
+			vreg->pdata->init_data.constraints.valid_modes_mask
+			      &= ~(REGULATOR_MODE_NORMAL | REGULATOR_MODE_IDLE);
+
+		vreg->rdev = regulator_register(rdesc, &pdev->dev,
+				&vreg->pdata->init_data, vreg);
+		if (IS_ERR(vreg->rdev)) {
+			rc = PTR_ERR(vreg->rdev);
+			pr_err("%s: regulator_register failed for %s, rc=%d\n",
+				__func__, reg_name, rc);
+		}
+	} else {
+		rc = -ENODEV;
+	}
+
+bail:
+	if (rc)
+		pr_err("%s: error for %s, rc=%d\n", __func__, reg_name, rc);
+
+	return rc;
+}
+
+static int __devexit pm8901_vreg_remove(struct platform_device *pdev)
+{
+	regulator_unregister(pm8901_vreg[pdev->id].rdev);
+	return 0;
+}
+
+static struct platform_driver pm8901_vreg_driver = {
+	.probe = pm8901_vreg_probe,
+	.remove = __devexit_p(pm8901_vreg_remove),
+	.driver = {
+		.name = "pm8901-regulator",
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init pm8901_vreg_init(void)
+{
+	return platform_driver_register(&pm8901_vreg_driver);
+}
+
+static void __exit pm8901_vreg_exit(void)
+{
+	platform_driver_unregister(&pm8901_vreg_driver);
+}
+
+static void print_write_error(struct pm8901_vreg *vreg, int rc,
+				const char *func)
+{
+	const char *reg_name = NULL;
+	ptrdiff_t id = vreg - pm8901_vreg;
+
+	if (id >= 0 && id < PM8901_VREG_MAX)
+		reg_name = pm8901_vreg_descrip[id].name;
+	pr_err("%s: pm8901_vreg_write failed for %s, rc=%d\n",
+		func, reg_name, rc);
+}
+
+subsys_initcall(pm8901_vreg_init);
+module_exit(pm8901_vreg_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("PMIC8901 regulator driver");
+MODULE_VERSION("1.0");
+MODULE_ALIAS("platform:pm8901-regulator");