[PATCH] LP3971 PMIC regulator driver

From: Marek Szyprowski
Date: Thu May 14 2009 - 03:35:24 EST

This patch adds regulator drivers for National Semiconductors LP3971 PMIC.
This LP3971 PMIC controller has 3 DC/DC voltage converters and 5 low drop-out
(LDO) regulators. LP3971 PMIC controller uses I2C interface.

Reviewed-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index e58c0ce..a2c899a 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -91,4 +91,11 @@ config REGULATOR_PCF50633
Say Y here to support the voltage regulators and convertors
on PCF50633

+config REGULATOR_LP3971
+ tristate "National Semiconductors LP3971 PMIC regulator driver"
+ depends on I2C
+ help
+ Say Y here to support the voltage regulators and convertors
+ on National Semiconductors LP3971 PMIC
+
endif
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index bac133a..f77a15a 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_REGULATOR_FIXED_VOLTAGE) += fixed.o
obj-$(CONFIG_REGULATOR_VIRTUAL_CONSUMER) += virtual.o

obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o
+obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o
obj-$(CONFIG_REGULATOR_TWL4030) += twl4030-regulator.o
obj-$(CONFIG_REGULATOR_WM8350) += wm8350-regulator.o
obj-$(CONFIG_REGULATOR_WM8400) += wm8400-regulator.o
diff --git a/drivers/regulator/lp3971.c b/drivers/regulator/lp3971.c
new file mode 100644
index 0000000..95c18bd
--- /dev/null
+++ b/drivers/regulator/lp3971.c
@@ -0,0 +1,532 @@
+/*
+ * Regulator driver for National Semiconductors LP3971 PMIC chip
+ *
+ * Copyright (C) 2009 Samsung Electronics
+ * Author: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
+ *
+ * Based on wm8350.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/lp3971.h>
+
+struct lp3971 {
+ struct device *dev;
+ struct mutex io_lock;
+ struct i2c_client *i2c;
+ int num_regulators;
+ struct regulator_dev **rdev;
+};
+
+static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
+static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val);
+
+#define LP3971_SYS_CONTROL1_REG 0x07
+
+#define LP3971_BUCK_VOL_ENABLE_REG 0x10
+#define LP3971_BUCK_VOL_CHANGE_REG 0x20
+
+/* Voltage control registers shift:
+ LP3971_BUCK1 -> 0
+ LP3971_BUCK2 -> 4
+ LP3971_BUCK3 -> 6
+*/
+#define BUCK_VOL_CHANGE_SHIFT(x) (((1 << x) & ~0x01) << 1)
+#define BUCK_VOL_CHANGE_FLAG_GO 0x01
+#define BUCK_VOL_CHANGE_FLAG_TARGET 0x02
+#define BUCK_VOL_CHANGE_FLAG_MASK 0x03
+
+#define LP3971_BUCK1_BASE 0x23
+#define LP3971_BUCK2_BASE 0x29
+#define LP3971_BUCK3_BASE 0x32
+
+const static int buck_base_addr[] = {
+ LP3971_BUCK1_BASE,
+ LP3971_BUCK2_BASE,
+ LP3971_BUCK3_BASE,
+};
+
+#define LP3971_BUCK_TARGET_VOL1_REG(x) (buck_base_addr[x])
+#define LP3971_BUCK_TARGET_VOL2_REG(x) (buck_base_addr[x]+1)
+
+const static int buck_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,
+};
+
+#define BUCK_TARGET_VOL_MASK 0x3f
+#define BUCK_TARGET_VOL_MIN_IDX 0x01
+#define BUCK_TARGET_VOL_MAX_IDX 0x19
+
+#define LP3971_BUCK_RAMP_REG(x) (buck_base_addr[x]+2)
+
+#define LP3971_LDO_ENABLE_REG 0x12
+#define LP3971_LDO_VOL_CONTR_BASE 0x39
+
+/* Voltage control registers:
+ LP3971_LDO1 -> LP3971_LDO_VOL_CONTR_BASE + 0
+ LP3971_LDO2 -> LP3971_LDO_VOL_CONTR_BASE + 0
+ LP3971_LDO3 -> LP3971_LDO_VOL_CONTR_BASE + 1
+ LP3971_LDO4 -> LP3971_LDO_VOL_CONTR_BASE + 1
+ LP3971_LDO5 -> LP3971_LDO_VOL_CONTR_BASE + 2
+*/
+#define LP3971_LDO_VOL_CONTR_REG(x) (LP3971_LDO_VOL_CONTR_BASE + (x >> 1))
+
+/* Voltage control registers shift:
+ LP3971_LDO1 -> 0, LP3971_LDO2 -> 4
+ LP3971_LDO3 -> 0, LP3971_LDO4 -> 4
+ LP3971_LDO5 -> 0
+*/
+#define LDO_VOL_CONTR_SHIFT(x) ((x & 1) << 2)
+#define LDO_VOL_CONTR_MASK 0x0f
+
+const static int ldo45_voltage_map1[] = {
+ 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350,
+ 1400, 1500, 1800, 1900, 2500, 2800, 3000, 3300,
+};
+
+const static int ldo123_voltage_map[] = {
+ 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
+ 2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300,
+};
+
+const static int *ldo_voltage_map[] = {
+ ldo123_voltage_map, /* LDO1 */
+ ldo123_voltage_map, /* LDO2 */
+ ldo123_voltage_map, /* LDO3 */
+ ldo45_voltage_map1, /* LDO4 */
+ ldo45_voltage_map1, /* LDO5 */
+};
+
+#define LDO_VOL_VALUE_MAP(x) (ldo_voltage_map[(x - LP3971_LDO1)])
+
+#define LDO_VOL_MIN_IDX 0x00
+#define LDO_VOL_MAX_IDX 0x0f
+
+static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3971_LDO1;
+ u16 mask = 1 << (1 + ldo);
+ u16 val;
+
+ val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
+ return (val & mask) != 0;
+}
+
+static int lp3971_ldo_enable(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3971_LDO1;
+ u16 mask = 1 << (1 + ldo);
+
+ return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
+}
+
+static int lp3971_ldo_disable(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3971_LDO1;
+ u16 mask = 1 << (1 + ldo);
+
+ return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
+}
+
+static int lp3971_ldo_get_voltage(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3971_LDO1;
+ u16 val, reg;
+
+ reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
+ val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
+
+ return 1000 * LDO_VOL_VALUE_MAP(ldo)[val];
+}
+
+static int lp3971_ldo_set_voltage(struct regulator_dev *dev,
+ int min_uV, int max_uV)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int ldo = rdev_get_id(dev) - LP3971_LDO1;
+ int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
+ const int *vol_map = LDO_VOL_VALUE_MAP(ldo);
+ u16 val;
+
+ if (min_vol < vol_map[LDO_VOL_MIN_IDX] ||
+ min_vol > vol_map[LDO_VOL_MAX_IDX])
+ return -EINVAL;
+
+ for (val = LDO_VOL_MIN_IDX; val <= LDO_VOL_MAX_IDX; val++)
+ if (vol_map[val] >= min_vol)
+ break;
+
+ if (vol_map[val] > max_vol)
+ return -EINVAL;
+
+ return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
+ LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo), val);
+}
+
+static struct regulator_ops lp3971_ldo_ops = {
+ .is_enabled = lp3971_ldo_is_enabled,
+ .enable = lp3971_ldo_enable,
+ .disable = lp3971_ldo_disable,
+ .get_voltage = lp3971_ldo_get_voltage,
+ .set_voltage = lp3971_ldo_set_voltage,
+};
+
+static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3971_DCDC1;
+ u16 mask = 1 << (buck * 2);
+ u16 val;
+
+ val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
+ return (val & mask) != 0;
+}
+
+static int lp3971_dcdc_enable(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3971_DCDC1;
+ u16 mask = 1 << (buck * 2);
+
+ return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
+}
+
+static int lp3971_dcdc_disable(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3971_DCDC1;
+ u16 mask = 1 << (buck * 2);
+
+ return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
+}
+
+static int lp3971_dcdc_get_voltage(struct regulator_dev *dev)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3971_DCDC1;
+ u16 reg;
+ int val;
+
+ reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
+ reg &= BUCK_TARGET_VOL_MASK;
+
+ if (reg <= BUCK_TARGET_VOL_MAX_IDX)
+ val = 1000 * buck_voltage_map[reg];
+ else
+ val = 0;
+
+ return val;
+}
+
+static int lp3971_dcdc_set_voltage(struct regulator_dev *dev,
+ int min_uV, int max_uV)
+{
+ struct lp3971 *lp3971 = rdev_get_drvdata(dev);
+ int buck = rdev_get_id(dev) - LP3971_DCDC1;
+ int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
+ const int *vol_map = buck_voltage_map;
+ u16 val;
+ int ret;
+
+ if (min_vol < vol_map[BUCK_TARGET_VOL_MIN_IDX] ||
+ min_vol > vol_map[BUCK_TARGET_VOL_MAX_IDX])
+ return -EINVAL;
+
+ for (val = BUCK_TARGET_VOL_MIN_IDX; val <= BUCK_TARGET_VOL_MAX_IDX;
+ val++)
+ if (vol_map[val] >= min_vol)
+ break;
+
+ if (vol_map[val] > max_vol)
+ return -EINVAL;
+
+ ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
+ BUCK_TARGET_VOL_MASK, val);
+ if (ret)
+ return ret;
+
+ ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
+ BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
+ BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
+ if (ret)
+ return ret;
+
+ return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
+ BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
+ 0 << BUCK_VOL_CHANGE_SHIFT(buck));
+}
+
+static struct regulator_ops lp3971_dcdc_ops = {
+ .is_enabled = lp3971_dcdc_is_enabled,
+ .enable = lp3971_dcdc_enable,
+ .disable = lp3971_dcdc_disable,
+ .get_voltage = lp3971_dcdc_get_voltage,
+ .set_voltage = lp3971_dcdc_set_voltage,
+};
+
+static struct regulator_desc regulators[] = {
+ {
+ .name = "LDO1",
+ .id = LP3971_LDO1,
+ .ops = &lp3971_ldo_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO2",
+ .id = LP3971_LDO2,
+ .ops = &lp3971_ldo_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO3",
+ .id = LP3971_LDO3,
+ .ops = &lp3971_ldo_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO4",
+ .id = LP3971_LDO4,
+ .ops = &lp3971_ldo_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "LDO5",
+ .id = LP3971_LDO5,
+ .ops = &lp3971_ldo_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "DCDC1",
+ .id = LP3971_DCDC1,
+ .ops = &lp3971_dcdc_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "DCDC2",
+ .id = LP3971_DCDC2,
+ .ops = &lp3971_dcdc_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+ {
+ .name = "DCDC3",
+ .id = LP3971_DCDC3,
+ .ops = &lp3971_dcdc_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int lp3971_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 || count != 1)
+ return -EIO;
+
+ *dest = ret;
+ return 0;
+}
+
+static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
+ const u16 *src)
+{
+ int ret;
+
+ if (count != 1)
+ return -EIO;
+ ret = i2c_smbus_write_byte_data(i2c, reg, *src);
+ if (ret >= 0)
+ return 0;
+
+ return ret;
+}
+
+static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
+{
+ u16 val = 0;
+
+ mutex_lock(&lp3971->io_lock);
+
+ lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
+
+ dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
+ (unsigned)val&0xff);
+
+ mutex_unlock(&lp3971->io_lock);
+
+ return val & 0xff;
+}
+
+static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
+{
+ u16 tmp;
+ int ret;
+
+ mutex_lock(&lp3971->io_lock);
+
+ ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
+ tmp = (tmp & ~mask) | val;
+ if (ret == 0) {
+ ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
+ dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
+ (unsigned)val&0xff);
+ }
+ mutex_unlock(&lp3971->io_lock);
+
+ return ret;
+}
+
+static int setup_regulators(struct lp3971 *lp3971,
+ struct lp3971_platform_data *pdata)
+{
+ int i, err;
+ int num_regulators = pdata->num_regulators;
+ lp3971->num_regulators = num_regulators;
+ lp3971->rdev = kzalloc(sizeof(struct regulator_dev *) * num_regulators,
+ GFP_KERNEL);
+
+ /* Instantiate the regulators */
+ for (i = 0; i < num_regulators; i++) {
+ int id = pdata->regulators[i].id;
+ lp3971->rdev[i] = regulator_register(&regulators[id],
+ lp3971->dev, pdata->regulators[i].initdata, lp3971);
+
+ err = IS_ERR(lp3971->rdev[i]);
+ if (err) {
+ dev_err(lp3971->dev, "regulator init failed: %d\n",
+ err);
+ goto error;
+ }
+ }
+
+ return 0;
+error:
+ for (i = 0; i < num_regulators; i++)
+ if (lp3971->rdev[i])
+ regulator_unregister(lp3971->rdev[i]);
+ kfree(lp3971->rdev);
+ lp3971->rdev = NULL;
+ return err;
+}
+
+static int __devinit lp3971_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct lp3971 *lp3971;
+ struct lp3971_platform_data *pdata = i2c->dev.platform_data;
+ int ret;
+ u16 val;
+
+ lp3971 = kzalloc(sizeof(struct lp3971), GFP_KERNEL);
+ if (lp3971 == NULL) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ lp3971->i2c = i2c;
+ lp3971->dev = &i2c->dev;
+ i2c_set_clientdata(i2c, lp3971);
+
+ mutex_init(&lp3971->io_lock);
+
+ /* Detect LP3971 (initial system control 1 reg is '0x60') */
+ ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
+ if (ret < 0) {
+ dev_err(&i2c->dev, "failed to detect device\n");
+ goto err_detect;
+ }
+
+ if (pdata) {
+ ret = setup_regulators(lp3971, pdata);
+ if (ret < 0)
+ goto err_detect;
+ } else
+ dev_warn(lp3971->dev, "No platform init data supplied\n");
+
+ return 0;
+
+err_detect:
+ i2c_set_clientdata(i2c, NULL);
+ kfree(lp3971);
+err:
+ return ret;
+}
+
+static int __devexit lp3971_i2c_remove(struct i2c_client *i2c)
+{
+ struct lp3971 *lp3971 = i2c_get_clientdata(i2c);
+ int i;
+ for (i = 0; i < lp3971->num_regulators; i++)
+ if (lp3971->rdev[i])
+ regulator_unregister(lp3971->rdev[i]);
+ kfree(lp3971->rdev);
+ i2c_set_clientdata(i2c, NULL);
+ kfree(lp3971);
+
+ return 0;
+}
+
+static const struct i2c_device_id lp3971_i2c_id[] = {
+ { "lp3971", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
+
+static struct i2c_driver lp3971_i2c_driver = {
+ .driver = {
+ .name = "LP3971",
+ .owner = THIS_MODULE,
+ },
+ .probe = lp3971_i2c_probe,
+ .remove = lp3971_i2c_remove,
+ .id_table = lp3971_i2c_id,
+};
+
+static int __init lp3971_module_init(void)
+{
+ int ret = -ENODEV;
+
+ ret = i2c_add_driver(&lp3971_i2c_driver);
+ if (ret != 0)
+ pr_err("Failed to register I2C driver: %d\n", ret);
+
+ return ret;
+}
+module_init(lp3971_module_init);
+
+static void __exit lp3971_module_exit(void)
+{
+ i2c_del_driver(&lp3971_i2c_driver);
+}
+module_exit(lp3971_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("LP3971 PMIC driver");
diff --git a/include/linux/regulator/lp3971.h b/include/linux/regulator/lp3971.h
new file mode 100644
index 0000000..6140164
--- /dev/null
+++ b/include/linux/regulator/lp3971.h
@@ -0,0 +1,51 @@
+/*
+ * National Semiconductors LP3971 PMIC chip client interface
+ *
+ * Copyright (C) 2009 Samsung Electronics
+ * Author: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
+ *
+ * Based on wm8400.h
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef __LINUX_REGULATOR_LP3971_H
+#define __LINUX_REGULATOR_LP3971_H
+
+#include <linux/regulator/machine.h>
+
+#define LP3971_LDO1 0
+#define LP3971_LDO2 1
+#define LP3971_LDO3 2
+#define LP3971_LDO4 3
+#define LP3971_LDO5 4
+
+#define LP3971_DCDC1 5
+#define LP3971_DCDC2 6
+#define LP3971_DCDC3 7
+
+#define LP3971_NUM_REGULATORS 8
+
+struct lp3971_regulator_subdev {
+ int id;
+ struct regulator_init_data *initdata;
+};
+
+struct lp3971_platform_data {
+ int num_regulators;
+ struct lp3971_regulator_subdev *regulators;
+};
+
+#endif

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