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kernel/drivers/regulator/slg51000-regulator.c

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// SPDX-License-Identifier: GPL-2.0+
//
// SLG51000 High PSRR, Multi-Output Regulators
// Copyright (C) 2019 Dialog Semiconductor
//
// Author: Eric Jeong <eric.jeong.opensource@diasemi.com>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include "slg51000-regulator.h"
#define SLG51000_SCTL_EVT 7
#define SLG51000_MAX_EVT_REGISTER 8
#define SLG51000_LDOHP_LV_MIN 1200000
#define SLG51000_LDOHP_HV_MIN 2400000
enum slg51000_regulators {
SLG51000_REGULATOR_LDO1 = 0,
SLG51000_REGULATOR_LDO2,
SLG51000_REGULATOR_LDO3,
SLG51000_REGULATOR_LDO4,
SLG51000_REGULATOR_LDO5,
SLG51000_REGULATOR_LDO6,
SLG51000_REGULATOR_LDO7,
SLG51000_MAX_REGULATORS,
};
struct slg51000 {
struct device *dev;
struct regmap *regmap;
struct regulator_desc *rdesc[SLG51000_MAX_REGULATORS];
struct regulator_dev *rdev[SLG51000_MAX_REGULATORS];
struct gpio_desc *cs_gpiod;
int chip_irq;
};
struct slg51000_evt_sta {
unsigned int ereg;
unsigned int sreg;
};
static const struct slg51000_evt_sta es_reg[SLG51000_MAX_EVT_REGISTER] = {
{SLG51000_LDO1_EVENT, SLG51000_LDO1_STATUS},
{SLG51000_LDO2_EVENT, SLG51000_LDO2_STATUS},
{SLG51000_LDO3_EVENT, SLG51000_LDO3_STATUS},
{SLG51000_LDO4_EVENT, SLG51000_LDO4_STATUS},
{SLG51000_LDO5_EVENT, SLG51000_LDO5_STATUS},
{SLG51000_LDO6_EVENT, SLG51000_LDO6_STATUS},
{SLG51000_LDO7_EVENT, SLG51000_LDO7_STATUS},
{SLG51000_SYSCTL_EVENT, SLG51000_SYSCTL_STATUS},
};
static const struct regmap_range slg51000_writeable_ranges[] = {
regmap_reg_range(SLG51000_SYSCTL_MATRIX_CONF_A,
SLG51000_SYSCTL_MATRIX_CONF_A),
regmap_reg_range(SLG51000_LDO1_VSEL, SLG51000_LDO1_VSEL),
regmap_reg_range(SLG51000_LDO1_MINV, SLG51000_LDO1_MAXV),
regmap_reg_range(SLG51000_LDO1_IRQ_MASK, SLG51000_LDO1_IRQ_MASK),
regmap_reg_range(SLG51000_LDO2_VSEL, SLG51000_LDO2_VSEL),
regmap_reg_range(SLG51000_LDO2_MINV, SLG51000_LDO2_MAXV),
regmap_reg_range(SLG51000_LDO2_IRQ_MASK, SLG51000_LDO2_IRQ_MASK),
regmap_reg_range(SLG51000_LDO3_VSEL, SLG51000_LDO3_VSEL),
regmap_reg_range(SLG51000_LDO3_MINV, SLG51000_LDO3_MAXV),
regmap_reg_range(SLG51000_LDO3_IRQ_MASK, SLG51000_LDO3_IRQ_MASK),
regmap_reg_range(SLG51000_LDO4_VSEL, SLG51000_LDO4_VSEL),
regmap_reg_range(SLG51000_LDO4_MINV, SLG51000_LDO4_MAXV),
regmap_reg_range(SLG51000_LDO4_IRQ_MASK, SLG51000_LDO4_IRQ_MASK),
regmap_reg_range(SLG51000_LDO5_VSEL, SLG51000_LDO5_VSEL),
regmap_reg_range(SLG51000_LDO5_MINV, SLG51000_LDO5_MAXV),
regmap_reg_range(SLG51000_LDO5_IRQ_MASK, SLG51000_LDO5_IRQ_MASK),
regmap_reg_range(SLG51000_LDO6_VSEL, SLG51000_LDO6_VSEL),
regmap_reg_range(SLG51000_LDO6_MINV, SLG51000_LDO6_MAXV),
regmap_reg_range(SLG51000_LDO6_IRQ_MASK, SLG51000_LDO6_IRQ_MASK),
regmap_reg_range(SLG51000_LDO7_VSEL, SLG51000_LDO7_VSEL),
regmap_reg_range(SLG51000_LDO7_MINV, SLG51000_LDO7_MAXV),
regmap_reg_range(SLG51000_LDO7_IRQ_MASK, SLG51000_LDO7_IRQ_MASK),
regmap_reg_range(SLG51000_OTP_IRQ_MASK, SLG51000_OTP_IRQ_MASK),
};
static const struct regmap_range slg51000_readable_ranges[] = {
regmap_reg_range(SLG51000_SYSCTL_PATN_ID_B0,
SLG51000_SYSCTL_PATN_ID_B2),
regmap_reg_range(SLG51000_SYSCTL_SYS_CONF_A,
SLG51000_SYSCTL_SYS_CONF_A),
regmap_reg_range(SLG51000_SYSCTL_SYS_CONF_D,
SLG51000_SYSCTL_MATRIX_CONF_B),
regmap_reg_range(SLG51000_SYSCTL_REFGEN_CONF_C,
SLG51000_SYSCTL_UVLO_CONF_A),
regmap_reg_range(SLG51000_SYSCTL_FAULT_LOG1, SLG51000_SYSCTL_IRQ_MASK),
regmap_reg_range(SLG51000_IO_GPIO1_CONF, SLG51000_IO_GPIO_STATUS),
regmap_reg_range(SLG51000_LUTARRAY_LUT_VAL_0,
SLG51000_LUTARRAY_LUT_VAL_11),
regmap_reg_range(SLG51000_MUXARRAY_INPUT_SEL_0,
SLG51000_MUXARRAY_INPUT_SEL_63),
regmap_reg_range(SLG51000_PWRSEQ_RESOURCE_EN_0,
SLG51000_PWRSEQ_INPUT_SENSE_CONF_B),
regmap_reg_range(SLG51000_LDO1_VSEL, SLG51000_LDO1_VSEL),
regmap_reg_range(SLG51000_LDO1_MINV, SLG51000_LDO1_MAXV),
regmap_reg_range(SLG51000_LDO1_MISC1, SLG51000_LDO1_VSEL_ACTUAL),
regmap_reg_range(SLG51000_LDO1_EVENT, SLG51000_LDO1_IRQ_MASK),
regmap_reg_range(SLG51000_LDO2_VSEL, SLG51000_LDO2_VSEL),
regmap_reg_range(SLG51000_LDO2_MINV, SLG51000_LDO2_MAXV),
regmap_reg_range(SLG51000_LDO2_MISC1, SLG51000_LDO2_VSEL_ACTUAL),
regmap_reg_range(SLG51000_LDO2_EVENT, SLG51000_LDO2_IRQ_MASK),
regmap_reg_range(SLG51000_LDO3_VSEL, SLG51000_LDO3_VSEL),
regmap_reg_range(SLG51000_LDO3_MINV, SLG51000_LDO3_MAXV),
regmap_reg_range(SLG51000_LDO3_CONF1, SLG51000_LDO3_VSEL_ACTUAL),
regmap_reg_range(SLG51000_LDO3_EVENT, SLG51000_LDO3_IRQ_MASK),
regmap_reg_range(SLG51000_LDO4_VSEL, SLG51000_LDO4_VSEL),
regmap_reg_range(SLG51000_LDO4_MINV, SLG51000_LDO4_MAXV),
regmap_reg_range(SLG51000_LDO4_CONF1, SLG51000_LDO4_VSEL_ACTUAL),
regmap_reg_range(SLG51000_LDO4_EVENT, SLG51000_LDO4_IRQ_MASK),
regmap_reg_range(SLG51000_LDO5_VSEL, SLG51000_LDO5_VSEL),
regmap_reg_range(SLG51000_LDO5_MINV, SLG51000_LDO5_MAXV),
regmap_reg_range(SLG51000_LDO5_TRIM2, SLG51000_LDO5_TRIM2),
regmap_reg_range(SLG51000_LDO5_CONF1, SLG51000_LDO5_VSEL_ACTUAL),
regmap_reg_range(SLG51000_LDO5_EVENT, SLG51000_LDO5_IRQ_MASK),
regmap_reg_range(SLG51000_LDO6_VSEL, SLG51000_LDO6_VSEL),
regmap_reg_range(SLG51000_LDO6_MINV, SLG51000_LDO6_MAXV),
regmap_reg_range(SLG51000_LDO6_TRIM2, SLG51000_LDO6_TRIM2),
regmap_reg_range(SLG51000_LDO6_CONF1, SLG51000_LDO6_VSEL_ACTUAL),
regmap_reg_range(SLG51000_LDO6_EVENT, SLG51000_LDO6_IRQ_MASK),
regmap_reg_range(SLG51000_LDO7_VSEL, SLG51000_LDO7_VSEL),
regmap_reg_range(SLG51000_LDO7_MINV, SLG51000_LDO7_MAXV),
regmap_reg_range(SLG51000_LDO7_CONF1, SLG51000_LDO7_VSEL_ACTUAL),
regmap_reg_range(SLG51000_LDO7_EVENT, SLG51000_LDO7_IRQ_MASK),
regmap_reg_range(SLG51000_OTP_EVENT, SLG51000_OTP_EVENT),
regmap_reg_range(SLG51000_OTP_IRQ_MASK, SLG51000_OTP_IRQ_MASK),
regmap_reg_range(SLG51000_OTP_LOCK_OTP_PROG, SLG51000_OTP_LOCK_CTRL),
regmap_reg_range(SLG51000_LOCK_GLOBAL_LOCK_CTRL1,
SLG51000_LOCK_GLOBAL_LOCK_CTRL1),
};
static const struct regmap_range slg51000_volatile_ranges[] = {
regmap_reg_range(SLG51000_SYSCTL_FAULT_LOG1, SLG51000_SYSCTL_STATUS),
regmap_reg_range(SLG51000_IO_GPIO_STATUS, SLG51000_IO_GPIO_STATUS),
regmap_reg_range(SLG51000_LDO1_EVENT, SLG51000_LDO1_STATUS),
regmap_reg_range(SLG51000_LDO2_EVENT, SLG51000_LDO2_STATUS),
regmap_reg_range(SLG51000_LDO3_EVENT, SLG51000_LDO3_STATUS),
regmap_reg_range(SLG51000_LDO4_EVENT, SLG51000_LDO4_STATUS),
regmap_reg_range(SLG51000_LDO5_EVENT, SLG51000_LDO5_STATUS),
regmap_reg_range(SLG51000_LDO6_EVENT, SLG51000_LDO6_STATUS),
regmap_reg_range(SLG51000_LDO7_EVENT, SLG51000_LDO7_STATUS),
regmap_reg_range(SLG51000_OTP_EVENT, SLG51000_OTP_EVENT),
};
static const struct regmap_access_table slg51000_writeable_table = {
.yes_ranges = slg51000_writeable_ranges,
.n_yes_ranges = ARRAY_SIZE(slg51000_writeable_ranges),
};
static const struct regmap_access_table slg51000_readable_table = {
.yes_ranges = slg51000_readable_ranges,
.n_yes_ranges = ARRAY_SIZE(slg51000_readable_ranges),
};
static const struct regmap_access_table slg51000_volatile_table = {
.yes_ranges = slg51000_volatile_ranges,
.n_yes_ranges = ARRAY_SIZE(slg51000_volatile_ranges),
};
static const struct regmap_config slg51000_regmap_config = {
.reg_bits = 16,
.val_bits = 8,
.max_register = 0x8000,
.wr_table = &slg51000_writeable_table,
.rd_table = &slg51000_readable_table,
.volatile_table = &slg51000_volatile_table,
};
static const struct regulator_ops slg51000_regl_ops = {
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.is_enabled = regulator_is_enabled_regmap,
.list_voltage = regulator_list_voltage_linear,
.map_voltage = regulator_map_voltage_linear,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
};
static const struct regulator_ops slg51000_switch_ops = {
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.is_enabled = regulator_is_enabled_regmap,
};
static int slg51000_of_parse_cb(struct device_node *np,
const struct regulator_desc *desc,
struct regulator_config *config)
{
struct gpio_desc *ena_gpiod;
ena_gpiod = fwnode_gpiod_get_index(of_fwnode_handle(np), "enable", 0,
GPIOD_OUT_LOW |
GPIOD_FLAGS_BIT_NONEXCLUSIVE,
"gpio-en-ldo");
if (!IS_ERR(ena_gpiod))
config->ena_gpiod = ena_gpiod;
return 0;
}
#define SLG51000_REGL_DESC(_id, _name, _s_name, _min, _step) \
[SLG51000_REGULATOR_##_id] = { \
.name = #_name, \
.supply_name = _s_name, \
.id = SLG51000_REGULATOR_##_id, \
.of_match = of_match_ptr(#_name), \
.of_parse_cb = slg51000_of_parse_cb, \
.ops = &slg51000_regl_ops, \
.regulators_node = of_match_ptr("regulators"), \
.n_voltages = 256, \
.min_uV = _min, \
.uV_step = _step, \
.linear_min_sel = 0, \
.vsel_mask = SLG51000_VSEL_MASK, \
.vsel_reg = SLG51000_##_id##_VSEL, \
.enable_reg = SLG51000_SYSCTL_MATRIX_CONF_A, \
.enable_mask = BIT(SLG51000_REGULATOR_##_id), \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
}
static struct regulator_desc regls_desc[SLG51000_MAX_REGULATORS] = {
SLG51000_REGL_DESC(LDO1, ldo1, NULL, 2400000, 5000),
SLG51000_REGL_DESC(LDO2, ldo2, NULL, 2400000, 5000),
SLG51000_REGL_DESC(LDO3, ldo3, "vin3", 1200000, 10000),
SLG51000_REGL_DESC(LDO4, ldo4, "vin4", 1200000, 10000),
SLG51000_REGL_DESC(LDO5, ldo5, "vin5", 400000, 5000),
SLG51000_REGL_DESC(LDO6, ldo6, "vin6", 400000, 5000),
SLG51000_REGL_DESC(LDO7, ldo7, "vin7", 1200000, 10000),
};
static int slg51000_regulator_init(struct slg51000 *chip)
{
struct regulator_config config = { };
struct regulator_desc *rdesc;
unsigned int reg, val;
u8 vsel_range[2];
int id, ret = 0;
const unsigned int min_regs[SLG51000_MAX_REGULATORS] = {
SLG51000_LDO1_MINV, SLG51000_LDO2_MINV, SLG51000_LDO3_MINV,
SLG51000_LDO4_MINV, SLG51000_LDO5_MINV, SLG51000_LDO6_MINV,
SLG51000_LDO7_MINV,
};
for (id = 0; id < SLG51000_MAX_REGULATORS; id++) {
chip->rdesc[id] = &regls_desc[id];
rdesc = chip->rdesc[id];
config.regmap = chip->regmap;
config.dev = chip->dev;
config.driver_data = chip;
ret = regmap_bulk_read(chip->regmap, min_regs[id],
vsel_range, 2);
if (ret < 0) {
dev_err(chip->dev,
"Failed to read the MIN register\n");
return ret;
}
switch (id) {
case SLG51000_REGULATOR_LDO1:
case SLG51000_REGULATOR_LDO2:
if (id == SLG51000_REGULATOR_LDO1)
reg = SLG51000_LDO1_MISC1;
else
reg = SLG51000_LDO2_MISC1;
ret = regmap_read(chip->regmap, reg, &val);
if (ret < 0) {
dev_err(chip->dev,
"Failed to read voltage range of ldo%d\n",
id + 1);
return ret;
}
rdesc->linear_min_sel = vsel_range[0];
rdesc->n_voltages = vsel_range[1] + 1;
if (val & SLG51000_SEL_VRANGE_MASK)
rdesc->min_uV = SLG51000_LDOHP_HV_MIN
+ (vsel_range[0]
* rdesc->uV_step);
else
rdesc->min_uV = SLG51000_LDOHP_LV_MIN
+ (vsel_range[0]
* rdesc->uV_step);
break;
case SLG51000_REGULATOR_LDO5:
case SLG51000_REGULATOR_LDO6:
if (id == SLG51000_REGULATOR_LDO5)
reg = SLG51000_LDO5_TRIM2;
else
reg = SLG51000_LDO6_TRIM2;
ret = regmap_read(chip->regmap, reg, &val);
if (ret < 0) {
dev_err(chip->dev,
"Failed to read LDO mode register\n");
return ret;
}
if (val & SLG51000_SEL_BYP_MODE_MASK) {
rdesc->ops = &slg51000_switch_ops;
rdesc->n_voltages = 0;
rdesc->min_uV = 0;
rdesc->uV_step = 0;
rdesc->linear_min_sel = 0;
break;
}
fallthrough; /* to the check below */
default:
rdesc->linear_min_sel = vsel_range[0];
rdesc->n_voltages = vsel_range[1] + 1;
rdesc->min_uV = rdesc->min_uV
+ (vsel_range[0] * rdesc->uV_step);
break;
}
chip->rdev[id] = devm_regulator_register(chip->dev, rdesc,
&config);
if (IS_ERR(chip->rdev[id])) {
ret = PTR_ERR(chip->rdev[id]);
dev_err(chip->dev,
"Failed to register regulator(%s):%d\n",
chip->rdesc[id]->name, ret);
return ret;
}
}
return 0;
}
static irqreturn_t slg51000_irq_handler(int irq, void *data)
{
struct slg51000 *chip = data;
struct regmap *regmap = chip->regmap;
enum { R0 = 0, R1, R2, REG_MAX };
u8 evt[SLG51000_MAX_EVT_REGISTER][REG_MAX];
int ret, i, handled = IRQ_NONE;
unsigned int evt_otp, mask_otp;
/* Read event[R0], status[R1] and mask[R2] register */
for (i = 0; i < SLG51000_MAX_EVT_REGISTER; i++) {
ret = regmap_bulk_read(regmap, es_reg[i].ereg, evt[i], REG_MAX);
if (ret < 0) {
dev_err(chip->dev,
"Failed to read event registers(%d)\n", ret);
return IRQ_NONE;
}
}
ret = regmap_read(regmap, SLG51000_OTP_EVENT, &evt_otp);
if (ret < 0) {
dev_err(chip->dev,
"Failed to read otp event registers(%d)\n", ret);
return IRQ_NONE;
}
ret = regmap_read(regmap, SLG51000_OTP_IRQ_MASK, &mask_otp);
if (ret < 0) {
dev_err(chip->dev,
"Failed to read otp mask register(%d)\n", ret);
return IRQ_NONE;
}
if ((evt_otp & SLG51000_EVT_CRC_MASK) &&
!(mask_otp & SLG51000_IRQ_CRC_MASK)) {
dev_info(chip->dev,
"OTP has been read or OTP crc is not zero\n");
handled = IRQ_HANDLED;
}
for (i = 0; i < SLG51000_MAX_REGULATORS; i++) {
if (!(evt[i][R2] & SLG51000_IRQ_ILIM_FLAG_MASK) &&
(evt[i][R0] & SLG51000_EVT_ILIM_FLAG_MASK)) {
regulator_notifier_call_chain(chip->rdev[i],
REGULATOR_EVENT_OVER_CURRENT, NULL);
if (evt[i][R1] & SLG51000_STA_ILIM_FLAG_MASK)
dev_warn(chip->dev,
"Over-current limit(ldo%d)\n", i + 1);
handled = IRQ_HANDLED;
}
}
if (!(evt[SLG51000_SCTL_EVT][R2] & SLG51000_IRQ_HIGH_TEMP_WARN_MASK) &&
(evt[SLG51000_SCTL_EVT][R0] & SLG51000_EVT_HIGH_TEMP_WARN_MASK)) {
for (i = 0; i < SLG51000_MAX_REGULATORS; i++) {
if (!(evt[i][R1] & SLG51000_STA_ILIM_FLAG_MASK) &&
(evt[i][R1] & SLG51000_STA_VOUT_OK_FLAG_MASK)) {
regulator_notifier_call_chain(chip->rdev[i],
REGULATOR_EVENT_OVER_TEMP, NULL);
}
}
handled = IRQ_HANDLED;
if (evt[SLG51000_SCTL_EVT][R1] &
SLG51000_STA_HIGH_TEMP_WARN_MASK)
dev_warn(chip->dev, "High temperature warning!\n");
}
return handled;
}
static void slg51000_clear_fault_log(struct slg51000 *chip)
{
unsigned int val = 0;
int ret = 0;
ret = regmap_read(chip->regmap, SLG51000_SYSCTL_FAULT_LOG1, &val);
if (ret < 0) {
dev_err(chip->dev, "Failed to read Fault log register\n");
return;
}
if (val & SLG51000_FLT_OVER_TEMP_MASK)
dev_dbg(chip->dev, "Fault log: FLT_OVER_TEMP\n");
if (val & SLG51000_FLT_POWER_SEQ_CRASH_REQ_MASK)
dev_dbg(chip->dev, "Fault log: FLT_POWER_SEQ_CRASH_REQ\n");
if (val & SLG51000_FLT_RST_MASK)
dev_dbg(chip->dev, "Fault log: FLT_RST\n");
if (val & SLG51000_FLT_POR_MASK)
dev_dbg(chip->dev, "Fault log: FLT_POR\n");
}
static int slg51000_i2c_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct slg51000 *chip;
struct gpio_desc *cs_gpiod;
int error, ret;
chip = devm_kzalloc(dev, sizeof(struct slg51000), GFP_KERNEL);
if (!chip)
return -ENOMEM;
cs_gpiod = devm_gpiod_get_optional(dev, "dlg,cs",
GPIOD_OUT_HIGH |
GPIOD_FLAGS_BIT_NONEXCLUSIVE);
if (IS_ERR(cs_gpiod))
return PTR_ERR(cs_gpiod);
if (cs_gpiod) {
dev_info(dev, "Found chip selector property\n");
chip->cs_gpiod = cs_gpiod;
}
usleep_range(10000, 11000);
i2c_set_clientdata(client, chip);
chip->chip_irq = client->irq;
chip->dev = dev;
chip->regmap = devm_regmap_init_i2c(client, &slg51000_regmap_config);
if (IS_ERR(chip->regmap)) {
error = PTR_ERR(chip->regmap);
dev_err(dev, "Failed to allocate register map: %d\n",
error);
return error;
}
ret = slg51000_regulator_init(chip);
if (ret < 0) {
dev_err(chip->dev, "Failed to init regulator(%d)\n", ret);
return ret;
}
slg51000_clear_fault_log(chip);
if (chip->chip_irq) {
ret = devm_request_threaded_irq(dev, chip->chip_irq, NULL,
slg51000_irq_handler,
(IRQF_TRIGGER_HIGH |
IRQF_ONESHOT),
"slg51000-irq", chip);
if (ret != 0) {
dev_err(dev, "Failed to request IRQ: %d\n",
chip->chip_irq);
return ret;
}
} else {
dev_info(dev, "No IRQ configured\n");
}
return ret;
}
static const struct i2c_device_id slg51000_i2c_id[] = {
{"slg51000", 0},
{},
};
MODULE_DEVICE_TABLE(i2c, slg51000_i2c_id);
static struct i2c_driver slg51000_regulator_driver = {
.driver = {
.name = "slg51000-regulator",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe_new = slg51000_i2c_probe,
.id_table = slg51000_i2c_id,
};
module_i2c_driver(slg51000_regulator_driver);
MODULE_AUTHOR("Eric Jeong <eric.jeong.opensource@diasemi.com>");
MODULE_DESCRIPTION("SLG51000 regulator driver");
MODULE_LICENSE("GPL");
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