Linux-libre 4.5-gnu

3 files changed, 481 insertions, 0 deletions

diff --git a/drivers/iio/health/Kconfig b/drivers/iio/health/Kconfig
new file mode 100644
index 000000000..a647679da
--- /dev/null
+++ b/drivers/iio/health/Kconfig
@@ -0,0 +1,21 @@
+#
+# Health sensors
+#
+# When adding new entries keep the list in alphabetical order
+
+menu "Health sensors"
+
+config MAX30100
+	tristate "MAX30100 heart rate and pulse oximeter sensor"
+	depends on I2C
+	select REGMAP_I2C
+	select IIO_BUFFER
+	select IIO_KFIFO_BUF
+	help
+	  Say Y here to build I2C interface support for the Maxim
+	  MAX30100 heart rate, and pulse oximeter sensor.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called max30100.
+
+endmenu
diff --git a/drivers/iio/health/Makefile b/drivers/iio/health/Makefile
new file mode 100644
index 000000000..7c475d7fa
--- /dev/null
+++ b/drivers/iio/health/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for IIO Health sensors
+#
+
+# When adding new entries keep the list in alphabetical order
+
+obj-$(CONFIG_MAX30100)		+= max30100.o
diff --git a/drivers/iio/health/max30100.c b/drivers/iio/health/max30100.c
new file mode 100644
index 000000000..9d1c81f91
--- /dev/null
+++ b/drivers/iio/health/max30100.c
@@ -0,0 +1,453 @@
+/*
+ * max30100.c - Support for MAX30100 heart rate and pulse oximeter sensor
+ *
+ * Copyright (C) 2015 Matt Ranostay <mranostay@gmail.com>
+ *
+ * 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.
+ *
+ * TODO: allow LED current and pulse length controls via device tree properties
+ */
+
+#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/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+
+#define MAX30100_REGMAP_NAME	"max30100_regmap"
+#define MAX30100_DRV_NAME	"max30100"
+
+#define MAX30100_REG_INT_STATUS			0x00
+#define MAX30100_REG_INT_STATUS_PWR_RDY		BIT(0)
+#define MAX30100_REG_INT_STATUS_SPO2_RDY	BIT(4)
+#define MAX30100_REG_INT_STATUS_HR_RDY		BIT(5)
+#define MAX30100_REG_INT_STATUS_FIFO_RDY	BIT(7)
+
+#define MAX30100_REG_INT_ENABLE			0x01
+#define MAX30100_REG_INT_ENABLE_SPO2_EN		BIT(0)
+#define MAX30100_REG_INT_ENABLE_HR_EN		BIT(1)
+#define MAX30100_REG_INT_ENABLE_FIFO_EN		BIT(3)
+#define MAX30100_REG_INT_ENABLE_MASK		0xf0
+#define MAX30100_REG_INT_ENABLE_MASK_SHIFT	4
+
+#define MAX30100_REG_FIFO_WR_PTR		0x02
+#define MAX30100_REG_FIFO_OVR_CTR		0x03
+#define MAX30100_REG_FIFO_RD_PTR		0x04
+#define MAX30100_REG_FIFO_DATA			0x05
+#define MAX30100_REG_FIFO_DATA_ENTRY_COUNT	16
+#define MAX30100_REG_FIFO_DATA_ENTRY_LEN	4
+
+#define MAX30100_REG_MODE_CONFIG		0x06
+#define MAX30100_REG_MODE_CONFIG_MODE_SPO2_EN	BIT(0)
+#define MAX30100_REG_MODE_CONFIG_MODE_HR_EN	BIT(1)
+#define MAX30100_REG_MODE_CONFIG_MODE_MASK	0x03
+#define MAX30100_REG_MODE_CONFIG_TEMP_EN	BIT(3)
+#define MAX30100_REG_MODE_CONFIG_PWR		BIT(7)
+
+#define MAX30100_REG_SPO2_CONFIG		0x07
+#define MAX30100_REG_SPO2_CONFIG_100HZ		BIT(2)
+#define MAX30100_REG_SPO2_CONFIG_HI_RES_EN	BIT(6)
+#define MAX30100_REG_SPO2_CONFIG_1600US		0x3
+
+#define MAX30100_REG_LED_CONFIG			0x09
+#define MAX30100_REG_LED_CONFIG_RED_LED_SHIFT	4
+
+#define MAX30100_REG_LED_CONFIG_24MA		0x07
+#define MAX30100_REG_LED_CONFIG_50MA		0x0f
+
+#define MAX30100_REG_TEMP_INTEGER		0x16
+#define MAX30100_REG_TEMP_FRACTION		0x17
+
+struct max30100_data {
+	struct i2c_client *client;
+	struct iio_dev *indio_dev;
+	struct mutex lock;
+	struct regmap *regmap;
+
+	__be16 buffer[2]; /* 2 16-bit channels */
+};
+
+static bool max30100_is_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case MAX30100_REG_INT_STATUS:
+	case MAX30100_REG_MODE_CONFIG:
+	case MAX30100_REG_FIFO_WR_PTR:
+	case MAX30100_REG_FIFO_OVR_CTR:
+	case MAX30100_REG_FIFO_RD_PTR:
+	case MAX30100_REG_FIFO_DATA:
+	case MAX30100_REG_TEMP_INTEGER:
+	case MAX30100_REG_TEMP_FRACTION:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static const struct regmap_config max30100_regmap_config = {
+	.name = MAX30100_REGMAP_NAME,
+
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = MAX30100_REG_TEMP_FRACTION,
+	.cache_type = REGCACHE_FLAT,
+
+	.volatile_reg = max30100_is_volatile_reg,
+};
+
+static const unsigned long max30100_scan_masks[] = {0x3, 0};
+
+static const struct iio_chan_spec max30100_channels[] = {
+	{
+		.type = IIO_INTENSITY,
+		.channel2 = IIO_MOD_LIGHT_IR,
+		.modified = 1,
+
+		.scan_index = 0,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_BE,
+		},
+	},
+	{
+		.type = IIO_INTENSITY,
+		.channel2 = IIO_MOD_LIGHT_RED,
+		.modified = 1,
+
+		.scan_index = 1,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_BE,
+		},
+	},
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = -1,
+	},
+};
+
+static int max30100_set_powermode(struct max30100_data *data, bool state)
+{
+	return regmap_update_bits(data->regmap, MAX30100_REG_MODE_CONFIG,
+				  MAX30100_REG_MODE_CONFIG_PWR,
+				  state ? 0 : MAX30100_REG_MODE_CONFIG_PWR);
+}
+
+static int max30100_clear_fifo(struct max30100_data *data)
+{
+	int ret;
+
+	ret = regmap_write(data->regmap, MAX30100_REG_FIFO_WR_PTR, 0);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(data->regmap, MAX30100_REG_FIFO_OVR_CTR, 0);
+	if (ret)
+		return ret;
+
+	return regmap_write(data->regmap, MAX30100_REG_FIFO_RD_PTR, 0);
+}
+
+static int max30100_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct max30100_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = max30100_set_powermode(data, true);
+	if (ret)
+		return ret;
+
+	return max30100_clear_fifo(data);
+}
+
+static int max30100_buffer_predisable(struct iio_dev *indio_dev)
+{
+	struct max30100_data *data = iio_priv(indio_dev);
+
+	return max30100_set_powermode(data, false);
+}
+
+static const struct iio_buffer_setup_ops max30100_buffer_setup_ops = {
+	.postenable = max30100_buffer_postenable,
+	.predisable = max30100_buffer_predisable,
+};
+
+static inline int max30100_fifo_count(struct max30100_data *data)
+{
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(data->regmap, MAX30100_REG_INT_STATUS, &val);
+	if (ret)
+		return ret;
+
+	/* FIFO is almost full */
+	if (val & MAX30100_REG_INT_STATUS_FIFO_RDY)
+		return MAX30100_REG_FIFO_DATA_ENTRY_COUNT - 1;
+
+	return 0;
+}
+
+static int max30100_read_measurement(struct max30100_data *data)
+{
+	int ret;
+
+	ret = i2c_smbus_read_i2c_block_data(data->client,
+					    MAX30100_REG_FIFO_DATA,
+					    MAX30100_REG_FIFO_DATA_ENTRY_LEN,
+					    (u8 *) &data->buffer);
+
+	return (ret == MAX30100_REG_FIFO_DATA_ENTRY_LEN) ? 0 : ret;
+}
+
+static irqreturn_t max30100_interrupt_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct max30100_data *data = iio_priv(indio_dev);
+	int ret, cnt = 0;
+
+	mutex_lock(&data->lock);
+
+	while (cnt-- || (cnt = max30100_fifo_count(data) > 0)) {
+		ret = max30100_read_measurement(data);
+		if (ret)
+			break;
+
+		iio_push_to_buffers(data->indio_dev, data->buffer);
+	}
+
+	mutex_unlock(&data->lock);
+
+	return IRQ_HANDLED;
+}
+
+static int max30100_chip_init(struct max30100_data *data)
+{
+	int ret;
+
+	/* RED IR LED = 24mA, IR LED = 50mA */
+	ret = regmap_write(data->regmap, MAX30100_REG_LED_CONFIG,
+				(MAX30100_REG_LED_CONFIG_24MA <<
+				 MAX30100_REG_LED_CONFIG_RED_LED_SHIFT) |
+				 MAX30100_REG_LED_CONFIG_50MA);
+	if (ret)
+		return ret;
+
+	/* enable hi-res SPO2 readings at 100Hz */
+	ret = regmap_write(data->regmap, MAX30100_REG_SPO2_CONFIG,
+				 MAX30100_REG_SPO2_CONFIG_HI_RES_EN |
+				 MAX30100_REG_SPO2_CONFIG_100HZ);
+	if (ret)
+		return ret;
+
+	/* enable SPO2 mode */
+	ret = regmap_update_bits(data->regmap, MAX30100_REG_MODE_CONFIG,
+				 MAX30100_REG_MODE_CONFIG_MODE_MASK,
+				 MAX30100_REG_MODE_CONFIG_MODE_HR_EN |
+				 MAX30100_REG_MODE_CONFIG_MODE_SPO2_EN);
+	if (ret)
+		return ret;
+
+	/* enable FIFO interrupt */
+	return regmap_update_bits(data->regmap, MAX30100_REG_INT_ENABLE,
+				 MAX30100_REG_INT_ENABLE_MASK,
+				 MAX30100_REG_INT_ENABLE_FIFO_EN
+				 << MAX30100_REG_INT_ENABLE_MASK_SHIFT);
+}
+
+static int max30100_read_temp(struct max30100_data *data, int *val)
+{
+	int ret;
+	unsigned int reg;
+
+	ret = regmap_read(data->regmap, MAX30100_REG_TEMP_INTEGER, &reg);
+	if (ret < 0)
+		return ret;
+	*val = reg << 4;
+
+	ret = regmap_read(data->regmap, MAX30100_REG_TEMP_FRACTION, &reg);
+	if (ret < 0)
+		return ret;
+
+	*val |= reg & 0xf;
+	*val = sign_extend32(*val, 11);
+
+	return 0;
+}
+
+static int max30100_get_temp(struct max30100_data *data, int *val)
+{
+	int ret;
+
+	/* start acquisition */
+	ret = regmap_update_bits(data->regmap, MAX30100_REG_MODE_CONFIG,
+				 MAX30100_REG_MODE_CONFIG_TEMP_EN,
+				 MAX30100_REG_MODE_CONFIG_TEMP_EN);
+	if (ret)
+		return ret;
+
+	usleep_range(35000, 50000);
+
+	return max30100_read_temp(data, val);
+}
+
+static int max30100_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct max30100_data *data = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		/*
+		 * Temperature reading can only be acquired while engine
+		 * is running
+		 */
+		mutex_lock(&indio_dev->mlock);
+
+		if (!iio_buffer_enabled(indio_dev))
+			ret = -EAGAIN;
+		else {
+			ret = max30100_get_temp(data, val);
+			if (!ret)
+				ret = IIO_VAL_INT;
+
+		}
+
+		mutex_unlock(&indio_dev->mlock);
+		break;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 1;  /* 0.0625 */
+		*val2 = 16;
+		ret = IIO_VAL_FRACTIONAL;
+		break;
+	}
+
+	return ret;
+}
+
+static const struct iio_info max30100_info = {
+	.driver_module = THIS_MODULE,
+	.read_raw = max30100_read_raw,
+};
+
+static int max30100_probe(struct i2c_client *client,
+			  const struct i2c_device_id *id)
+{
+	struct max30100_data *data;
+	struct iio_buffer *buffer;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	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 = MAX30100_DRV_NAME;
+	indio_dev->channels = max30100_channels;
+	indio_dev->info = &max30100_info;
+	indio_dev->num_channels = ARRAY_SIZE(max30100_channels);
+	indio_dev->available_scan_masks = max30100_scan_masks;
+	indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
+	indio_dev->setup_ops = &max30100_buffer_setup_ops;
+
+	data = iio_priv(indio_dev);
+	data->indio_dev = indio_dev;
+	data->client = client;
+
+	mutex_init(&data->lock);
+	i2c_set_clientdata(client, indio_dev);
+
+	data->regmap = devm_regmap_init_i2c(client, &max30100_regmap_config);
+	if (IS_ERR(data->regmap)) {
+		dev_err(&client->dev, "regmap initialization failed.\n");
+		return PTR_ERR(data->regmap);
+	}
+	max30100_set_powermode(data, false);
+
+	ret = max30100_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, max30100_interrupt_handler,
+					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					"max30100_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 max30100_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+	struct max30100_data *data = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+	max30100_set_powermode(data, false);
+
+	return 0;
+}
+
+static const struct i2c_device_id max30100_id[] = {
+	{ "max30100", 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, max30100_id);
+
+static const struct of_device_id max30100_dt_ids[] = {
+	{ .compatible = "maxim,max30100" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max30100_dt_ids);
+
+static struct i2c_driver max30100_driver = {
+	.driver = {
+		.name	= MAX30100_DRV_NAME,
+		.of_match_table	= of_match_ptr(max30100_dt_ids),
+	},
+	.probe		= max30100_probe,
+	.remove		= max30100_remove,
+	.id_table	= max30100_id,
+};
+module_i2c_driver(max30100_driver);
+
+MODULE_AUTHOR("Matt Ranostay <mranostay@gmail.com>");
+MODULE_DESCRIPTION("MAX30100 heart rate and pulse oximeter sensor");
+MODULE_LICENSE("GPL");