[PATCH] regulator: Add LTC3676 support

Tim Harvey tharvey at gateworks.com
Tue Sep 30 22:16:15 PDT 2014


This patch adds support for the Linear Technology LTC3676
8-output I2C voltage regulator IC.

Signed-off-by: Tim Harvey <tharvey at gateworks.com>
---
 Documentation/devicetree/bindings/ltc3676.txt | 103 ++++++
 drivers/regulator/Kconfig                     |   7 +
 drivers/regulator/Makefile                    |   1 +
 drivers/regulator/ltc3676.c                   | 506 ++++++++++++++++++++++++++
 4 files changed, 617 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/ltc3676.txt
 create mode 100644 drivers/regulator/ltc3676.c

diff --git a/Documentation/devicetree/bindings/ltc3676.txt b/Documentation/devicetree/bindings/ltc3676.txt
new file mode 100644
index 0000000..e004f89
--- /dev/null
+++ b/Documentation/devicetree/bindings/ltc3676.txt
@@ -0,0 +1,103 @@
+Linear Technology LTC3676 8-output regulators
+
+Required properties:
+- compatible: "lltc,ltc3676"
+- reg: I2C slave address
+
+Required child node:
+- regulators: Contains eight regulator child nodes sw1, sw2, sw3, sw4,
+  ldo1, ldo2, ldo3, and ldo4, specifying the initialization data as
+  documented in Documentation/devicetree/bindings/regulator/regulator.txt.
+
+Each regulator is defined using the standard binding for regulators. The
+nodes for sw1, sw2, sw3, sw4, ldo1, ldo2 and ldo4 additionally need to specify
+the resistor values of their external feedback voltage dividers:
+
+Required properties (not on ldo3):
+- lltc,fb-voltage-divider: An array of two integers containing the resistor
+  values R1 and R2 of the feedback voltage divider in ohms.
+
+Regulators sw1, sw2, sw3, sw4 can regulate the feedback reference from:
+412.5mV to 800mV in 12.5 mV steps. The output voltage thus ranges between
+0.4125 * (1 + R1/R2) V and 0.8 * (1 + R1/R2) V.
+
+Regulators ldo1, ldo2, and ldo4 have a fixed 0.725 V reference and thus output
+0.725 * (1 + R1/R2) V. The ldo3 regulator is fixed to 1.8 V.  The ldo1 standby
+regulator can not be disabled and thus should have the regulator-always-on
+property set.
+
+Example:
+
+	ltc3676: pmic at 3c {
+		compatible = "lltc,ltc3676";
+		reg = <0x3c>;
+
+		regulators {
+			sw1_reg: sw1 {
+				regulator-min-microvolt = <674400>;
+				regulator-max-microvolt = <1308000>;
+				lltc,fb-voltage-divider = <127000 200000>;
+				regulator-ramp-delay = <7000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			sw2_reg: sw2 {
+				regulator-min-microvolt = <1033310>;
+				regulator-max-microvolt = <200400>;
+				lltc,fb-voltage-divider = <301000 200000>;
+				regulator-ramp-delay = <7000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			sw3_reg: sw3 {
+				regulator-min-microvolt = <674400>;
+				regulator-max-microvolt = <130800>;
+				lltc,fb-voltage-divider = <127000 200000>;
+				regulator-ramp-delay = <7000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			sw4_reg: sw4 {
+				regulator-min-microvolt = <868310>;
+				regulator-max-microvolt = <168400>;
+				lltc,fb-voltage-divider = <221000 200000>;
+				regulator-ramp-delay = <7000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			/* unused */
+			ldo1_reg: ldo1 {
+				regulator-min-microvolt = <0>;
+				regulator-max-microvolt = <0>;
+				lltc,fb-voltage-divider = <0 0>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			ldo2_reg: ldo2 {
+				regulator-min-microvolt = <2490375>;
+				regulator-max-microvolt = <2490375>;
+				lltc,fb-voltage-divider = <487000 200000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+
+			ldo3_reg: ldo3 {
+				regulator-min-microvolt = <1800000>;
+				regulator-max-microvolt = <1800000>;
+				regulator-boot-on;
+			};
+
+			ldo4_reg: ldo4 {
+				regulator-min-microvolt = <3023250>;
+				regulator-max-microvolt = <3023250>;
+				lltc,fb-voltage-divider = <634000 200000>;
+				regulator-boot-on;
+				regulator-always-on;
+			};
+		};
+	};
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 2dc8289..dc33c42 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -290,6 +290,13 @@ config REGULATOR_LTC3589
 	  This enables support for the LTC3589, LTC3589-1, and LTC3589-2
 	  8-output regulators controlled via I2C.
 
+config REGULATOR_LTC3676
+	tristate "LTC3676 regulator driver"
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  Say y here to support for the LTC3676 regulators controlled via I2C.
+
 config REGULATOR_MAX14577
 	tristate "Maxim 14577/77836 regulator"
 	depends on MFD_MAX14577
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index aa4a6aa..0e7f416 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -40,6 +40,7 @@ obj-$(CONFIG_REGULATOR_LP8788) += lp8788-buck.o
 obj-$(CONFIG_REGULATOR_LP8788) += lp8788-ldo.o
 obj-$(CONFIG_REGULATOR_LP8755) += lp8755.o
 obj-$(CONFIG_REGULATOR_LTC3589) += ltc3589.o
+obj-$(CONFIG_REGULATOR_LTC3676) += ltc3676.o
 obj-$(CONFIG_REGULATOR_MAX14577) += max14577.o
 obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
 obj-$(CONFIG_REGULATOR_MAX8649)	+= max8649.o
diff --git a/drivers/regulator/ltc3676.c b/drivers/regulator/ltc3676.c
new file mode 100644
index 0000000..4ea6d97
--- /dev/null
+++ b/drivers/regulator/ltc3676.c
@@ -0,0 +1,506 @@
+/*
+ * Copyright (C) 2014 Gateworks Corporation, Inc. 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 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
+ */
+
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+
+#define DRIVER_NAME		"ltc3676"
+
+/* LTC3676 Registers */
+#define LTC3676_BUCK1     0x01
+#define LTC3676_BUCK2     0x02
+#define LTC3676_BUCK3     0x03
+#define LTC3676_BUCK4     0x04
+#define LTC3676_LDOA      0x05
+#define LTC3676_LDOB      0x06
+#define LTC3676_SQD1      0x07
+#define LTC3676_SQD2      0x08
+#define LTC3676_CNTRL     0x09
+#define LTC3676_DVB1A     0x0A
+#define LTC3676_DVB1B     0x0B
+#define LTC3676_DVB2A     0x0C
+#define LTC3676_DVB2B     0x0D
+#define LTC3676_DVB3A     0x0E
+#define LTC3676_DVB3B     0x0F
+#define LTC3676_DVB4A     0x10
+#define LTC3676_DVB4B     0x11
+#define LTC3676_MSKIRQ    0x12
+#define LTC3676_MSKPG     0x13
+#define LTC3676_USER      0x14
+#define LTC3676_IRQSTAT   0x15
+#define LTC3676_PGSTATL   0x16
+#define LTC3676_PGSTATRT  0x17
+#define LTC3676_HRST      0x1E
+#define LTC3676_CLIRQ     0x1F
+
+#define LTC3676_IRQSTAT_PGOOD_TIMEOUT	BIT(3)
+#define LTC3676_IRQSTAT_UNDERVOLT_WARN	BIT(4)
+#define LTC3676_IRQSTAT_UNDERVOLT_FAULT	BIT(5)
+#define LTC3676_IRQSTAT_THERMAL_WARN	BIT(6)
+#define LTC3676_IRQSTAT_THERMAL_FAULT	BIT(7)
+
+enum ltc3676_reg {
+	LTC3676_SW1,
+	LTC3676_SW2,
+	LTC3676_SW3,
+	LTC3676_SW4,
+	LTC3676_LDO1,
+	LTC3676_LDO2,
+	LTC3676_LDO3,
+	LTC3676_LDO4,
+	LTC3676_NUM_REGULATORS,
+};
+
+struct ltc3676_regulator {
+	struct regulator_desc desc;
+
+	/* External feedback voltage divider */
+	unsigned int r1;
+	unsigned int r2;
+};
+
+struct ltc3676 {
+	struct regmap *regmap;
+	struct device *dev;
+	struct ltc3676_regulator regulator_descs[LTC3676_NUM_REGULATORS];
+	struct regulator_dev *regulators[LTC3676_NUM_REGULATORS];
+};
+
+static int ltc3676_set_suspend_voltage(struct regulator_dev *rdev, int uV)
+{
+	struct ltc3676 *ltc3676 = rdev_get_drvdata(rdev);
+	struct device *dev = ltc3676->dev;
+	int dcdc = rdev_get_id(rdev);
+	int sel;
+
+	dev_dbg(dev, "%s id=%d uV=%d\n", __func__, dcdc, uV);
+	sel = regulator_map_voltage_linear(rdev, uV, uV);
+	if (sel < 0)
+		return sel;
+
+	/* DVBB register follows right after the corresponding DVBA register */
+	return regmap_update_bits(ltc3676->regmap, rdev->desc->vsel_reg + 1,
+				  rdev->desc->vsel_mask, sel);
+}
+
+static int ltc3676_set_suspend_mode(struct regulator_dev *rdev,
+				    unsigned int mode)
+{
+	struct ltc3676 *ltc3676= rdev_get_drvdata(rdev);
+	struct device *dev = ltc3676->dev;
+	int mask, bit = 0;
+	int dcdc = rdev_get_id(rdev);
+
+	dev_dbg(dev, "%s id=%d mode=%d\n", __func__, dcdc, mode);
+
+	/* DVB reference select is bit5 of DVBA reg */
+	mask = 1 << 5;
+
+	if (mode != REGULATOR_MODE_STANDBY)
+		bit = mask;	/* Select DVBB */
+
+	return regmap_update_bits(ltc3676->regmap, rdev->desc->vsel_reg,
+				  mask, bit);
+}
+
+/* SW1, SW2, SW3, SW4 linear 0.8V-3.3V with scalar via R1/R2 feeback res */
+static struct regulator_ops ltc3676_linear_regulator_ops =
+{
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+	.list_voltage = regulator_list_voltage_linear,
+	.set_voltage_sel = regulator_set_voltage_sel_regmap,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+	.set_suspend_voltage = ltc3676_set_suspend_voltage,
+	.set_suspend_mode = ltc3676_set_suspend_mode,
+};
+
+/* LDO1 always on fixed 0.8V-3.3V via scalar via R1/R2 feeback res */
+static struct regulator_ops ltc3676_fixed_standby_regulator_ops = {
+};
+
+/* LDO2, LDO3 fixed (LDO2 has external scalar via R1/R2 feedback res) */
+static struct regulator_ops ltc3676_fixed_regulator_ops = 
+{
+	.enable = regulator_enable_regmap,
+	.disable = regulator_disable_regmap,
+	.is_enabled = regulator_is_enabled_regmap,
+};
+
+#define LTC3676_REG(_name, _ops, en_reg, en_bit, dvba_reg, dvb_mask)   \
+	[LTC3676_ ## _name] = {                                        \
+		.desc = {                                              \
+			.name = #_name,                                \
+			.n_voltages = (dvb_mask) + 1,                  \
+			.min_uV = (dvba_reg) ? 412500 : 0,             \
+			.uV_step = (dvba_reg) ? 12500 : 0,             \
+			.ramp_delay = (dvba_reg) ? 800 : 0,            \
+			.fixed_uV = (dvb_mask) ? 0 : 725000,           \
+			.ops = &ltc3676_ ## _ops ## _regulator_ops,    \
+			.type = REGULATOR_VOLTAGE,                     \
+			.id = LTC3676_ ## _name,                       \
+			.owner = THIS_MODULE,                          \
+			.vsel_reg = (dvba_reg),                        \
+			.vsel_mask = (dvb_mask),                       \
+			.enable_reg = (en_reg),                        \
+			.enable_mask = (1 << en_bit),                  \
+		},                                                     \
+	}
+
+#define LTC3676_LINEAR_REG(_name, _en, _dvba)                          \
+	LTC3676_REG(_name, linear,                                     \
+		    LTC3676_ ## _en, 7,                                \
+		    LTC3676_ ## _dvba, 0x1f)
+
+#define LTC3676_FIXED_REG(_name, _en_reg, _en_bit) \
+	LTC3676_REG(_name, fixed, LTC3676_ ## _en_reg, _en_bit, 0, 0)
+
+static struct ltc3676_regulator ltc3676_regulators[LTC3676_NUM_REGULATORS] = {
+	LTC3676_LINEAR_REG(SW1, BUCK1, DVB1A),
+	LTC3676_LINEAR_REG(SW2, BUCK2, DVB2A),
+	LTC3676_LINEAR_REG(SW3, BUCK3, DVB3A),
+	LTC3676_LINEAR_REG(SW4, BUCK4, DVB4A),
+	LTC3676_REG(LDO1, fixed_standby, 0, 0, 0, 0),
+	LTC3676_FIXED_REG(LDO2, LDOA, 2),
+	LTC3676_FIXED_REG(LDO3, LDOA, 5),
+	LTC3676_FIXED_REG(LDO4, LDOB, 2),
+};
+
+#ifdef CONFIG_OF
+static struct of_regulator_match ltc3676_matches[] = {
+	{ .name = "sw1",	},
+	{ .name = "sw2",	},
+	{ .name = "sw3",	},
+	{ .name = "sw4",	},
+	{ .name = "ldo1",	},
+	{ .name = "ldo2",	},
+	{ .name = "ldo3",	},
+	{ .name = "ldo4",	},
+};
+
+static int ltc3676_parse_regulators_dt(struct ltc3676 *ltc3676)
+{
+	struct device *dev = ltc3676->dev;
+	struct device_node *node;
+	int i, ret;
+
+	node = of_find_node_by_name(dev->of_node, "regulators");
+	if (!node) {
+		dev_err(dev, "regulators node not found\n");
+		return -EINVAL;
+	}
+
+	ret = of_regulator_match(dev, node, ltc3676_matches,
+				 ARRAY_SIZE(ltc3676_matches));
+	of_node_put(node);
+	if (ret < 0) {
+		dev_err(dev, "Error parsing regulator init data: %d\n", ret);
+		return -EINVAL;
+	}
+	if (ret != LTC3676_NUM_REGULATORS) {
+		dev_err(dev, "Only %d regulators described in device tree\n",
+			ret);
+		return -EINVAL;
+	}
+
+	/* parse feedback voltage deviders: LDO3 doesn't have them */
+	for (i = 0; i < LTC3676_NUM_REGULATORS; i++) {
+		struct ltc3676_regulator *desc = &ltc3676->regulator_descs[i];
+		struct device_node *np = ltc3676_matches[i].of_node;
+		u32 vdiv[2];
+
+		if (i == LTC3676_LDO3)
+			continue;
+		ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider",
+						 vdiv, 2);
+		if (ret) {
+			dev_err(dev, "Failed to parse voltage divider: %d\n",
+				ret);
+			return ret;
+		}
+
+		desc->r1 = vdiv[0];
+		desc->r2 = vdiv[1];
+	}
+
+	return 0;
+}
+
+static inline struct regulator_init_data *match_init_data(int index)
+{
+	return ltc3676_matches[index].init_data;
+}
+
+static inline struct device_node *match_of_node(int index)
+{
+	return ltc3676_matches[index].of_node;
+}
+#else
+static int ltc3676_parse_regulators_dt(struct ltc3676_chip *chip)
+{
+	return 0;
+}
+
+static inline struct regulator_init_data *match_init_data(int index)
+{
+	return NULL;
+}
+
+static inline struct device_node *match_of_node(int index)
+{
+	return NULL;
+}
+#endif
+
+static bool ltc3676_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+		case LTC3676_IRQSTAT:
+		case LTC3676_BUCK1:
+		case LTC3676_BUCK2:
+		case LTC3676_BUCK3:
+		case LTC3676_BUCK4:
+		case LTC3676_LDOA:
+		case LTC3676_LDOB:
+		case LTC3676_SQD1:
+		case LTC3676_SQD2:
+		case LTC3676_CNTRL:
+		case LTC3676_DVB1A:
+		case LTC3676_DVB1B:
+		case LTC3676_DVB2A:
+		case LTC3676_DVB2B:
+		case LTC3676_DVB3A:
+		case LTC3676_DVB3B:
+		case LTC3676_DVB4A:
+		case LTC3676_DVB4B:
+		case LTC3676_MSKIRQ:
+		case LTC3676_MSKPG:
+		case LTC3676_USER:
+		case LTC3676_HRST:
+		case LTC3676_CLIRQ:
+			return true;
+	}
+	return false;
+}
+
+static bool ltc3676_readable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+		case LTC3676_IRQSTAT:
+		case LTC3676_BUCK1:
+		case LTC3676_BUCK2:
+		case LTC3676_BUCK3:
+		case LTC3676_BUCK4:
+		case LTC3676_LDOA:
+		case LTC3676_LDOB:
+		case LTC3676_SQD1:
+		case LTC3676_SQD2:
+		case LTC3676_CNTRL:
+		case LTC3676_DVB1A:
+		case LTC3676_DVB1B:
+		case LTC3676_DVB2A:
+		case LTC3676_DVB2B:
+		case LTC3676_DVB3A:
+		case LTC3676_DVB3B:
+		case LTC3676_DVB4A:
+		case LTC3676_DVB4B:
+		case LTC3676_MSKIRQ:
+		case LTC3676_MSKPG:
+		case LTC3676_USER:
+		case LTC3676_HRST:
+		case LTC3676_CLIRQ:
+			return true;
+	}
+	return false;
+}
+
+static bool ltc3676_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+		case LTC3676_IRQSTAT:
+		case LTC3676_PGSTATL:
+		case LTC3676_PGSTATRT:
+			return true;
+	}
+	return false;
+}
+
+static const struct regmap_config ltc3676_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.writeable_reg = ltc3676_writeable_reg,
+	.readable_reg = ltc3676_readable_reg,
+	.volatile_reg = ltc3676_volatile_reg,
+	.max_register = LTC3676_CLIRQ,
+	.use_single_rw = true,
+	.cache_type = REGCACHE_RBTREE,
+};
+
+static irqreturn_t ltc3676_isr(int irq, void *dev_id)
+{
+	struct ltc3676 *ltc3676 = dev_id;
+	struct device *dev = ltc3676->dev;
+	unsigned int i, irqstat, event;
+
+	regmap_read(ltc3676->regmap, LTC3676_IRQSTAT, &irqstat);
+
+	dev_dbg(dev, "irq%d irqstat=0x%02x\n", irq, irqstat);
+	if (irqstat & LTC3676_IRQSTAT_THERMAL_WARN) {
+		dev_info(dev, "Over-temperature Warning\n");
+		event = REGULATOR_EVENT_OVER_TEMP;
+		for (i = 0; i < LTC3676_NUM_REGULATORS; i++)
+			regulator_notifier_call_chain(ltc3676->regulators[i],
+						      event, NULL);
+	}
+
+	if (irqstat & LTC3676_IRQSTAT_UNDERVOLT_WARN) {
+		dev_info(dev, "Undervoltage Warning\n");
+		event = REGULATOR_EVENT_UNDER_VOLTAGE;
+		for (i = 0; i < LTC3676_NUM_REGULATORS; i++)
+			regulator_notifier_call_chain(ltc3676->regulators[i],
+						      event, NULL);
+	}
+
+	/* Clear warning condition */
+	regmap_write(ltc3676->regmap, LTC3676_CLIRQ, 0);
+
+	return IRQ_HANDLED;
+}
+
+static inline unsigned int ltc3676_scale(unsigned int uV, u32 r1, u32 r2)
+{
+	uint64_t tmp;
+	if (uV == 0)
+		return 0;
+	tmp = (uint64_t)uV * r1;
+	do_div(tmp, r2);
+	return uV + (unsigned int)tmp;
+}
+
+static void ltc3676_apply_fb_voltage_divider(struct ltc3676_regulator *rdesc)
+{
+	struct regulator_desc *desc = &rdesc->desc;
+
+	if (!rdesc->r1 || !rdesc->r2)
+		return;
+
+	desc->min_uV = ltc3676_scale(desc->min_uV, rdesc->r1, rdesc->r2);
+	desc->uV_step = ltc3676_scale(desc->uV_step, rdesc->r1, rdesc->r2);
+	desc->fixed_uV = ltc3676_scale(desc->fixed_uV, rdesc->r1, rdesc->r2);
+}
+
+static int ltc3676_regulator_probe(struct i2c_client *client,
+				    const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct ltc3676_regulator *descs;
+	struct ltc3676 *ltc3676;
+	int i, ret;
+
+	ltc3676 = devm_kzalloc(dev, sizeof(*ltc3676), GFP_KERNEL);
+	if (!ltc3676)
+		return -ENOMEM;
+
+	i2c_set_clientdata(client, ltc3676);
+	ltc3676->dev = dev;
+
+	descs = ltc3676->regulator_descs;
+	memcpy(descs, ltc3676_regulators, sizeof(ltc3676_regulators));
+	descs[LTC3676_LDO3].desc.fixed_uV = 1800000;
+
+	ltc3676->regmap = devm_regmap_init_i2c(client, &ltc3676_regmap_config);
+	if (IS_ERR(ltc3676->regmap)) {
+		ret = PTR_ERR(ltc3676->regmap);
+		dev_err(dev, "failed to initialize regmap: %d\n", ret);
+		return ret;
+	}
+
+	ret = ltc3676_parse_regulators_dt(ltc3676);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < LTC3676_NUM_REGULATORS; i++) {
+		struct ltc3676_regulator *rdesc = &ltc3676->regulator_descs[i];
+		struct regulator_desc *desc = &rdesc->desc;
+		struct regulator_init_data *init_data;
+		struct regulator_config config = { };
+
+		init_data = match_init_data(i);
+
+		if (i != LTC3676_LDO3) {
+			/* skip unused (defined by r1=r2=0) */
+			if (rdesc->r1 == 0 && rdesc->r2 == 0)
+				continue;
+			ltc3676_apply_fb_voltage_divider(rdesc);
+		}
+
+		config.dev = dev;
+		config.init_data = init_data;
+		config.driver_data = ltc3676;
+		config.of_node = match_of_node(i);
+
+		ltc3676->regulators[i] = devm_regulator_register(dev, desc,
+								 &config);
+		if (IS_ERR(ltc3676->regulators[i])) {
+			ret = PTR_ERR(ltc3676->regulators[i]);
+			dev_err(dev, "failed to register regulator %s: %d\n",
+				desc->name, ret);
+			return ret;
+		}
+	}
+
+	regmap_write(ltc3676->regmap, LTC3676_CLIRQ, 0);
+	ret = devm_request_threaded_irq(dev, client->irq, NULL, ltc3676_isr,
+					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+					client->name, ltc3676);
+	if (ret) {
+		dev_err(dev, "Failed to request IRQ: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct i2c_device_id ltc3676_i2c_id[] = {
+	{ "ltc3676" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ltc3676_i2c_id);
+
+static struct i2c_driver ltc3676_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+	},
+	.probe = ltc3676_regulator_probe,
+	.id_table = ltc3676_i2c_id,
+};
+module_i2c_driver(ltc3676_driver);
+
+MODULE_AUTHOR("Tim Harvey <tharvey at gateworks.com>");
+MODULE_DESCRIPTION("Regulator Driver for Linear Technology LTC1376");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("i2c:ltc3676");
-- 
1.8.3.2




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