// SPDX-License-Identifier: GPL-2.0-or-later /* * max30102.c - Support for MAX30102 heart rate and pulse oximeter sensor * * Copyright (C) 2017 Matt Ranostay * * Support for MAX30105 optical particle sensor * Copyright (C) 2017 Peter Meerwald-Stadler * * 7-bit I2C chip address: 0x57 * TODO: proximity power saving feature */ #include #include #include #include #include #include #include #include #include #include #include #include #include #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); } 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); } #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); } 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); } 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; } #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); /* fall through */ case 2: MAX30102_COPY_DATA(1); /* fall through */ case 1: MAX30102_COPY_DATA(0); break; default: return -EINVAL; } return (ret == measurements * MAX30102_REG_FIFO_DATA_BYTES) ? 0 : -EINVAL; } 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; } 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; } 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, ®); 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, ®); 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, ®); 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); } 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); } 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, ®); if (ret < 0) return ret; *val = reg << 4; ret = regmap_read(data->regmap, MAX30102_REG_TEMP_FRACTION, ®); if (ret < 0) return ret; *val |= reg & 0xf; *val = sign_extend32(*val, 11); return 0; } 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; } 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; } 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, ®); if (ret) return ret; if (reg != MAX30102_PART_NUMBER) return -ENODEV; /* show revision ID */ ret = regmap_read(data->regmap, MAX30102_REG_REV_ID, ®); 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); } 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; } 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 "); MODULE_DESCRIPTION("MAX30102 heart rate/pulse oximeter and MAX30105 particle sensor driver"); MODULE_LICENSE("GPL");