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Release 4.16 drivers/iio/health/max30102.c

/*
 * max30102.c - Support for MAX30102 heart rate and pulse oximeter sensor
 *
 * Copyright (C) 2017 Matt Ranostay <matt@ranostay.consulting>
 *
 * Support for MAX30105 optical particle sensor
 * Copyright (C) 2017 Peter Meerwald-Stadler <pmeerw@pmeerw.net>
 *
 * 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.
 *
 * 7-bit I2C chip address: 0x57
 * TODO: proximity power saving feature
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/irq.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/regmap.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/kfifo_buf.h>


#define MAX30102_REGMAP_NAME	"max30102_regmap"

#define MAX30102_DRV_NAME	"max30102"

#define MAX30102_PART_NUMBER	0x15


enum max30102_chip_id {
	
max30102,
	
max30105,
};


enum max3012_led_idx {
	
MAX30102_LED_RED,
	
MAX30102_LED_IR,
	
MAX30105_LED_GREEN,
};


#define MAX30102_REG_INT_STATUS			0x00

#define MAX30102_REG_INT_STATUS_PWR_RDY		BIT(0)

#define MAX30102_REG_INT_STATUS_PROX_INT	BIT(4)

#define MAX30102_REG_INT_STATUS_ALC_OVF		BIT(5)

#define MAX30102_REG_INT_STATUS_PPG_RDY		BIT(6)

#define MAX30102_REG_INT_STATUS_FIFO_RDY	BIT(7)


#define MAX30102_REG_INT_ENABLE			0x02

#define MAX30102_REG_INT_ENABLE_PROX_INT_EN	BIT(4)

#define MAX30102_REG_INT_ENABLE_ALC_OVF_EN	BIT(5)

#define MAX30102_REG_INT_ENABLE_PPG_EN		BIT(6)

#define MAX30102_REG_INT_ENABLE_FIFO_EN		BIT(7)

#define MAX30102_REG_INT_ENABLE_MASK		0xf0

#define MAX30102_REG_INT_ENABLE_MASK_SHIFT	4


#define MAX30102_REG_FIFO_WR_PTR		0x04

#define MAX30102_REG_FIFO_OVR_CTR		0x05

#define MAX30102_REG_FIFO_RD_PTR		0x06

#define MAX30102_REG_FIFO_DATA			0x07

#define MAX30102_REG_FIFO_DATA_BYTES		3


#define MAX30102_REG_FIFO_CONFIG		0x08

#define MAX30102_REG_FIFO_CONFIG_AVG_4SAMPLES	BIT(1)

#define MAX30102_REG_FIFO_CONFIG_AVG_SHIFT	5

#define MAX30102_REG_FIFO_CONFIG_AFULL		BIT(0)


#define MAX30102_REG_MODE_CONFIG		0x09

#define MAX30102_REG_MODE_CONFIG_MODE_NONE	0x00

#define MAX30102_REG_MODE_CONFIG_MODE_HR	0x02 
/* red LED */

#define MAX30102_REG_MODE_CONFIG_MODE_HR_SPO2	0x03 
/* red + IR LED */

#define MAX30102_REG_MODE_CONFIG_MODE_MULTI	0x07 
/* multi-LED mode */

#define MAX30102_REG_MODE_CONFIG_MODE_MASK	GENMASK(2, 0)

#define MAX30102_REG_MODE_CONFIG_PWR		BIT(7)


#define MAX30102_REG_MODE_CONTROL_SLOT21	0x11 
/* multi-LED control */

#define MAX30102_REG_MODE_CONTROL_SLOT43	0x12

#define MAX30102_REG_MODE_CONTROL_SLOT_MASK	(GENMASK(6, 4) | GENMASK(2, 0))

#define MAX30102_REG_MODE_CONTROL_SLOT_SHIFT	4


#define MAX30102_REG_SPO2_CONFIG		0x0a

#define MAX30102_REG_SPO2_CONFIG_PULSE_411_US	0x03

#define MAX30102_REG_SPO2_CONFIG_SR_400HZ	0x03

#define MAX30102_REG_SPO2_CONFIG_SR_MASK	0x07

#define MAX30102_REG_SPO2_CONFIG_SR_MASK_SHIFT	2

#define MAX30102_REG_SPO2_CONFIG_ADC_4096_STEPS	BIT(0)

#define MAX30102_REG_SPO2_CONFIG_ADC_MASK_SHIFT	5


#define MAX30102_REG_RED_LED_CONFIG		0x0c

#define MAX30102_REG_IR_LED_CONFIG		0x0d

#define MAX30105_REG_GREEN_LED_CONFIG		0x0e


#define MAX30102_REG_TEMP_CONFIG		0x21

#define MAX30102_REG_TEMP_CONFIG_TEMP_EN	BIT(0)


#define MAX30102_REG_TEMP_INTEGER		0x1f

#define MAX30102_REG_TEMP_FRACTION		0x20


#define MAX30102_REG_REV_ID			0xfe

#define MAX30102_REG_PART_ID			0xff


struct max30102_data {
	
struct i2c_client *client;
	
struct iio_dev *indio_dev;
	
struct mutex lock;
	
struct regmap *regmap;
	
enum max30102_chip_id chip_id;

	
u8 buffer[12];
	
__be32 processed_buffer[3]; /* 3 x 18-bit (padded to 32-bits) */
};


static const struct regmap_config max30102_regmap_config = {
	.name = MAX30102_REGMAP_NAME,

	.reg_bits = 8,
	.val_bits = 8,
};


static const unsigned long max30102_scan_masks[] = {
	BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR),
	0
};


static const unsigned long max30105_scan_masks[] = {
	BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR),
	BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR) |
		BIT(MAX30105_LED_GREEN),
	0
};


#define MAX30102_INTENSITY_CHANNEL(_si, _mod) { \
                .type = IIO_INTENSITY, \
                .channel2 = _mod, \
                .modified = 1, \
                .scan_index = _si, \
                .scan_type = { \
                        .sign = 'u', \
                        .shift = 8, \
                        .realbits = 18, \
                        .storagebits = 32, \
                        .endianness = IIO_BE, \
                }, \
        }


static const struct iio_chan_spec max30102_channels[] = {
	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_RED, IIO_MOD_LIGHT_RED),
	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_IR, IIO_MOD_LIGHT_IR),
	{
		.type = IIO_TEMP,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
		.scan_index = -1,
        },
};


static const struct iio_chan_spec max30105_channels[] = {
	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_RED, IIO_MOD_LIGHT_RED),
	MAX30102_INTENSITY_CHANNEL(MAX30102_LED_IR, IIO_MOD_LIGHT_IR),
	MAX30102_INTENSITY_CHANNEL(MAX30105_LED_GREEN, IIO_MOD_LIGHT_GREEN),
	{
		.type = IIO_TEMP,
		.info_mask_separate =
			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
		.scan_index = -1,
        },
};


static int max30102_set_power(struct max30102_data *data, bool en) { return regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONFIG, MAX30102_REG_MODE_CONFIG_PWR, en ? 0 : MAX30102_REG_MODE_CONFIG_PWR); }

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Matthew Ranostay2990.62%150.00%
Peter Meerwald-Stadler39.38%150.00%
Total32100.00%2100.00%


static int max30102_set_powermode(struct max30102_data *data, u8 mode, bool en) { u8 reg = mode; if (!en) reg |= MAX30102_REG_MODE_CONFIG_PWR; return regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONFIG, MAX30102_REG_MODE_CONFIG_PWR | MAX30102_REG_MODE_CONFIG_MODE_MASK, reg); }

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Peter Meerwald-Stadler47100.00%1100.00%
Total47100.00%1100.00%

#define MAX30102_MODE_CONTROL_LED_SLOTS(slot2, slot1) \ ((slot2 << MAX30102_REG_MODE_CONTROL_SLOT_SHIFT) | slot1)
static int max30102_buffer_postenable(struct iio_dev *indio_dev) { struct max30102_data *data = iio_priv(indio_dev); int ret; u8 reg; switch (*indio_dev->active_scan_mask) { case BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR): reg = MAX30102_REG_MODE_CONFIG_MODE_HR_SPO2; break; case BIT(MAX30102_LED_RED) | BIT(MAX30102_LED_IR) | BIT(MAX30105_LED_GREEN): ret = regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONTROL_SLOT21, MAX30102_REG_MODE_CONTROL_SLOT_MASK, MAX30102_MODE_CONTROL_LED_SLOTS(2, 1)); if (ret) return ret; ret = regmap_update_bits(data->regmap, MAX30102_REG_MODE_CONTROL_SLOT43, MAX30102_REG_MODE_CONTROL_SLOT_MASK, MAX30102_MODE_CONTROL_LED_SLOTS(0, 3)); if (ret) return ret; reg = MAX30102_REG_MODE_CONFIG_MODE_MULTI; break; default: return -EINVAL; } return max30102_set_powermode(data, reg, true); }

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Peter Meerwald-Stadler11379.58%266.67%
Matthew Ranostay2920.42%133.33%
Total142100.00%3100.00%


static int max30102_buffer_predisable(struct iio_dev *indio_dev) { struct max30102_data *data = iio_priv(indio_dev); return max30102_set_powermode(data, MAX30102_REG_MODE_CONFIG_MODE_NONE, false); }

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Matthew Ranostay2993.55%150.00%
Peter Meerwald-Stadler26.45%150.00%
Total31100.00%2100.00%

static const struct iio_buffer_setup_ops max30102_buffer_setup_ops = { .postenable = max30102_buffer_postenable, .predisable = max30102_buffer_predisable, };
static inline int max30102_fifo_count(struct max30102_data *data) { unsigned int val; int ret; ret = regmap_read(data->regmap, MAX30102_REG_INT_STATUS, &val); if (ret) return ret; /* FIFO has one sample slot left */ if (val & MAX30102_REG_INT_STATUS_FIFO_RDY) return 1; return 0; }

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Matthew Ranostay53100.00%1100.00%
Total53100.00%1100.00%

#define MAX30102_COPY_DATA(i) \ memcpy(&data->processed_buffer[(i)], \ &buffer[(i) * MAX30102_REG_FIFO_DATA_BYTES], \ MAX30102_REG_FIFO_DATA_BYTES)
static int max30102_read_measurement(struct max30102_data *data, unsigned int measurements) { int ret; u8 *buffer = (u8 *) &data->buffer; ret = i2c_smbus_read_i2c_block_data(data->client, MAX30102_REG_FIFO_DATA, measurements * MAX30102_REG_FIFO_DATA_BYTES, buffer); switch (measurements) { case 3: MAX30102_COPY_DATA(2); case 2: /* fall-through */ MAX30102_COPY_DATA(1); case 1: /* fall-through */ MAX30102_COPY_DATA(0); break; default: return -EINVAL; } return (ret == measurements * MAX30102_REG_FIFO_DATA_BYTES) ? 0 : -EINVAL; }

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Matthew Ranostay5959.00%133.33%
Peter Meerwald-Stadler4141.00%266.67%
Total100100.00%3100.00%


static irqreturn_t max30102_interrupt_handler(int irq, void *private) { struct iio_dev *indio_dev = private; struct max30102_data *data = iio_priv(indio_dev); unsigned int measurements = bitmap_weight(indio_dev->active_scan_mask, indio_dev->masklength); int ret, cnt = 0; mutex_lock(&data->lock); while (cnt || (cnt = max30102_fifo_count(data)) > 0) { ret = max30102_read_measurement(data, measurements); if (ret) break; iio_push_to_buffers(data->indio_dev, data->processed_buffer); cnt--; } mutex_unlock(&data->lock); return IRQ_HANDLED; }

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Matthew Ranostay9985.34%150.00%
Peter Meerwald-Stadler1714.66%150.00%
Total116100.00%2100.00%


static int max30102_get_current_idx(unsigned int val, int *reg) { /* each step is 0.200 mA */ *reg = val / 200; return *reg > 0xff ? -EINVAL : 0; }

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Matthew Ranostay33100.00%1100.00%
Total33100.00%1100.00%


static int max30102_led_init(struct max30102_data *data) { struct device *dev = &data->client->dev; struct device_node *np = dev->of_node; unsigned int val; int reg, ret; ret = of_property_read_u32(np, "maxim,red-led-current-microamp", &val); if (ret) { dev_info(dev, "no red-led-current-microamp set\n"); /* Default to 7 mA RED LED */ val = 7000; } ret = max30102_get_current_idx(val, &reg); if (ret) { dev_err(dev, "invalid RED LED current setting %d\n", val); return ret; } ret = regmap_write(data->regmap, MAX30102_REG_RED_LED_CONFIG, reg); if (ret) return ret; if (data->chip_id == max30105) { ret = of_property_read_u32(np, "maxim,green-led-current-microamp", &val); if (ret) { dev_info(dev, "no green-led-current-microamp set\n"); /* Default to 7 mA green LED */ val = 7000; } ret = max30102_get_current_idx(val, &reg); if (ret) { dev_err(dev, "invalid green LED current setting %d\n", val); return ret; } ret = regmap_write(data->regmap, MAX30105_REG_GREEN_LED_CONFIG, reg); if (ret) return ret; } ret = of_property_read_u32(np, "maxim,ir-led-current-microamp", &val); if (ret) { dev_info(dev, "no ir-led-current-microamp set\n"); /* Default to 7 mA IR LED */ val = 7000; } ret = max30102_get_current_idx(val, &reg); if (ret) { dev_err(dev, "invalid IR LED current setting %d\n", val); return ret; } return regmap_write(data->regmap, MAX30102_REG_IR_LED_CONFIG, reg); }

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Matthew Ranostay18867.87%133.33%
Peter Meerwald-Stadler8932.13%266.67%
Total277100.00%3100.00%


static int max30102_chip_init(struct max30102_data *data) { int ret; /* setup LED current settings */ ret = max30102_led_init(data); if (ret) return ret; /* configure 18-bit HR + SpO2 readings at 400Hz */ ret = regmap_write(data->regmap, MAX30102_REG_SPO2_CONFIG, (MAX30102_REG_SPO2_CONFIG_ADC_4096_STEPS << MAX30102_REG_SPO2_CONFIG_ADC_MASK_SHIFT) | (MAX30102_REG_SPO2_CONFIG_SR_400HZ << MAX30102_REG_SPO2_CONFIG_SR_MASK_SHIFT) | MAX30102_REG_SPO2_CONFIG_PULSE_411_US); if (ret) return ret; /* average 4 samples + generate FIFO interrupt */ ret = regmap_write(data->regmap, MAX30102_REG_FIFO_CONFIG, (MAX30102_REG_FIFO_CONFIG_AVG_4SAMPLES << MAX30102_REG_FIFO_CONFIG_AVG_SHIFT) | MAX30102_REG_FIFO_CONFIG_AFULL); if (ret) return ret; /* enable FIFO interrupt */ return regmap_update_bits(data->regmap, MAX30102_REG_INT_ENABLE, MAX30102_REG_INT_ENABLE_MASK, MAX30102_REG_INT_ENABLE_FIFO_EN); }

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Matthew Ranostay10399.04%150.00%
Peter Meerwald-Stadler10.96%150.00%
Total104100.00%2100.00%


static int max30102_read_temp(struct max30102_data *data, int *val) { int ret; unsigned int reg; ret = regmap_read(data->regmap, MAX30102_REG_TEMP_INTEGER, &reg); if (ret < 0) return ret; *val = reg << 4; ret = regmap_read(data->regmap, MAX30102_REG_TEMP_FRACTION, &reg); if (ret < 0) return ret; *val |= reg & 0xf; *val = sign_extend32(*val, 11); return 0; }

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Matthew Ranostay96100.00%1100.00%
Total96100.00%1100.00%


static int max30102_get_temp(struct max30102_data *data, int *val, bool en) { int ret; if (en) { ret = max30102_set_power(data, true); if (ret) return ret; } /* start acquisition */ ret = regmap_update_bits(data->regmap, MAX30102_REG_TEMP_CONFIG, MAX30102_REG_TEMP_CONFIG_TEMP_EN, MAX30102_REG_TEMP_CONFIG_TEMP_EN); if (ret) goto out; msleep(35); ret = max30102_read_temp(data, val); out: if (en) max30102_set_power(data, false); return ret; }

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Matthew Ranostay5052.08%133.33%
Peter Meerwald-Stadler4647.92%266.67%
Total96100.00%3100.00%


static int max30102_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct max30102_data *data = iio_priv(indio_dev); int ret = -EINVAL; switch (mask) { case IIO_CHAN_INFO_RAW: /* * Temperature reading can only be acquired when not in * shutdown; leave shutdown briefly when buffer not running */ mutex_lock(&indio_dev->mlock); if (!iio_buffer_enabled(indio_dev)) ret = max30102_get_temp(data, val, true); else ret = max30102_get_temp(data, val, false); mutex_unlock(&indio_dev->mlock); if (ret) return ret; ret = IIO_VAL_INT; break; case IIO_CHAN_INFO_SCALE: *val = 1000; /* 62.5 */ *val2 = 16; ret = IIO_VAL_FRACTIONAL; break; } return ret; }

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Matthew Ranostay11182.22%133.33%
Peter Meerwald-Stadler2417.78%266.67%
Total135100.00%3100.00%

static const struct iio_info max30102_info = { .read_raw = max30102_read_raw, };
static int max30102_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct max30102_data *data; struct iio_buffer *buffer; struct iio_dev *indio_dev; int ret; unsigned int reg; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); if (!indio_dev) return -ENOMEM; buffer = devm_iio_kfifo_allocate(&client->dev); if (!buffer) return -ENOMEM; iio_device_attach_buffer(indio_dev, buffer); indio_dev->name = MAX30102_DRV_NAME; indio_dev->info = &max30102_info; indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE); indio_dev->setup_ops = &max30102_buffer_setup_ops; indio_dev->dev.parent = &client->dev; data = iio_priv(indio_dev); data->indio_dev = indio_dev; data->client = client; data->chip_id = id->driver_data; mutex_init(&data->lock); i2c_set_clientdata(client, indio_dev); switch (data->chip_id) { case max30105: indio_dev->channels = max30105_channels; indio_dev->num_channels = ARRAY_SIZE(max30105_channels); indio_dev->available_scan_masks = max30105_scan_masks; break; case max30102: indio_dev->channels = max30102_channels; indio_dev->num_channels = ARRAY_SIZE(max30102_channels); indio_dev->available_scan_masks = max30102_scan_masks; break; default: return -ENODEV; } data->regmap = devm_regmap_init_i2c(client, &max30102_regmap_config); if (IS_ERR(data->regmap)) { dev_err(&client->dev, "regmap initialization failed\n"); return PTR_ERR(data->regmap); } /* check part ID */ ret = regmap_read(data->regmap, MAX30102_REG_PART_ID, &reg); if (ret) return ret; if (reg != MAX30102_PART_NUMBER) return -ENODEV; /* show revision ID */ ret = regmap_read(data->regmap, MAX30102_REG_REV_ID, &reg); if (ret) return ret; dev_dbg(&client->dev, "max3010x revision %02x\n", reg); /* clear mode setting, chip shutdown */ ret = max30102_set_powermode(data, MAX30102_REG_MODE_CONFIG_MODE_NONE, false); if (ret) return ret; ret = max30102_chip_init(data); if (ret) return ret; if (client->irq <= 0) { dev_err(&client->dev, "no valid irq defined\n"); return -EINVAL; } ret = devm_request_threaded_irq(&client->dev, client->irq, NULL, max30102_interrupt_handler, IRQF_TRIGGER_FALLING | IRQF_ONESHOT, "max30102_irq", indio_dev); if (ret) { dev_err(&client->dev, "request irq (%d) failed\n", client->irq); return ret; } return iio_device_register(indio_dev); }

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Matthew Ranostay29063.74%114.29%
Peter Meerwald-Stadler15433.85%571.43%
Lars-Peter Clausen112.42%114.29%
Total455100.00%7100.00%


static int max30102_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); struct max30102_data *data = iio_priv(indio_dev); iio_device_unregister(indio_dev); max30102_set_power(data, false); return 0; }

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Matthew Ranostay4597.83%150.00%
Peter Meerwald-Stadler12.17%150.00%
Total46100.00%2100.00%

static const struct i2c_device_id max30102_id[] = { { "max30102", max30102 }, { "max30105", max30105 }, {} }; MODULE_DEVICE_TABLE(i2c, max30102_id); static const struct of_device_id max30102_dt_ids[] = { { .compatible = "maxim,max30102" }, { .compatible = "maxim,max30105" }, { } }; MODULE_DEVICE_TABLE(of, max30102_dt_ids); static struct i2c_driver max30102_driver = { .driver = { .name = MAX30102_DRV_NAME, .of_match_table = of_match_ptr(max30102_dt_ids), }, .probe = max30102_probe, .remove = max30102_remove, .id_table = max30102_id, }; module_i2c_driver(max30102_driver); MODULE_AUTHOR("Matt Ranostay <matt@ranostay.consulting>"); MODULE_DESCRIPTION("MAX30102 heart rate/pulse oximeter and MAX30105 particle sensor driver"); MODULE_LICENSE("GPL");

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Matthew Ranostay166068.06%17.14%
Peter Meerwald-Stadler76831.49%1285.71%
Lars-Peter Clausen110.45%17.14%
Total2439100.00%14100.00%
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