#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/jiffies.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define MLX90614_OP_RAM 0x00
#define MLX90614_OP_EEPROM 0x20
#define MLX90614_OP_SLEEP 0xff
#define MLX90615_OP_EEPROM 0x10
#define MLX90615_OP_RAM 0x20
#define MLX90615_OP_SLEEP 0xc6
#define MLX90614_CONFIG_IIR_SHIFT 0 /* IIR coefficient */
#define MLX90614_CONFIG_IIR_MASK (0x7 << MLX90614_CONFIG_IIR_SHIFT)
#define MLX90614_CONFIG_DUAL_SHIFT 6 /* single (0) or dual (1) IR sensor */
#define MLX90614_CONFIG_DUAL_MASK (1 << MLX90614_CONFIG_DUAL_SHIFT)
#define MLX90614_CONFIG_FIR_SHIFT 8 /* FIR coefficient */
#define MLX90614_CONFIG_FIR_MASK (0x7 << MLX90614_CONFIG_FIR_SHIFT)
#define MLX90615_CONFIG_IIR_SHIFT 12 /* IIR coefficient */
#define MLX90615_CONFIG_IIR_MASK (0x7 << MLX90615_CONFIG_IIR_SHIFT)
#define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
#define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
#define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */
#define MLX90615_TIMING_WAKEUP 22 /* time to hold SCL low for wake-up */
#define MLX90614_AUTOSLEEP_DELAY 5000 /* default autosleep delay */
#define MLX90614_CONST_OFFSET_DEC -13657 /* decimal part of the Kelvin offset */
#define MLX90614_CONST_OFFSET_REM 500000 /* remainder of offset (273.15*50) */
#define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
#define MLX90614_CONST_FIR 0x7 /* Fixed value for FIR part of low pass filter */
#define field_get(_mask, _reg) (((_reg) & (_mask)) >> (ffs(_mask) - 1))
#define field_prep(_mask, _val) (((_val) << (ffs(_mask) - 1)) & (_mask))
struct mlx_chip_info {
u8 op_eeprom_emissivity;
u8 op_eeprom_config1;
u8 op_ram_ta;
u8 op_ram_tobj1;
u8 op_ram_tobj2;
u8 op_sleep;
u8 dual_channel;
u8 wakeup_delay_ms;
u16 emissivity_max;
u16 fir_config_mask;
u16 iir_config_mask;
int iir_valid_offset;
u16 iir_values[8];
int iir_freqs[8][2];
};
struct mlx90614_data {
struct i2c_client *client;
struct mutex lock;
struct gpio_desc *wakeup_gpio;
const struct mlx_chip_info *chip_info;
unsigned long ready_timestamp;
};
static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
u16 value)
{
union i2c_smbus_data data;
s32 ret;
dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);
data.word = 0x0000;
ret = i2c_smbus_xfer(client->adapter, client->addr,
client->flags | I2C_CLIENT_PEC,
I2C_SMBUS_WRITE, command,
I2C_SMBUS_WORD_DATA, &data);
if (ret < 0)
return ret;
msleep(MLX90614_TIMING_EEPROM);
data.word = value;
ret = i2c_smbus_xfer(client->adapter, client->addr,
client->flags | I2C_CLIENT_PEC,
I2C_SMBUS_WRITE, command,
I2C_SMBUS_WORD_DATA, &data);
msleep(MLX90614_TIMING_EEPROM);
return ret;
}
static inline s32 mlx90614_iir_search(const struct i2c_client *client,
int value)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct mlx90614_data *data = iio_priv(indio_dev);
const struct mlx_chip_info *chip_info = data->chip_info;
int i;
s32 ret;
for (i = chip_info->iir_valid_offset;
i < ARRAY_SIZE(chip_info->iir_values);
i++) {
if (value == chip_info->iir_values[i])
break;
}
if (i == ARRAY_SIZE(chip_info->iir_values))
return -EINVAL;
ret = i2c_smbus_read_word_data(client, chip_info->op_eeprom_config1);
if (ret < 0)
return ret;
if (chip_info->fir_config_mask) {
ret &= ~chip_info->fir_config_mask;
ret |= field_prep(chip_info->fir_config_mask, MLX90614_CONST_FIR);
}
ret &= ~chip_info->iir_config_mask;
ret |= field_prep(chip_info->iir_config_mask, i);
ret = mlx90614_write_word(client, chip_info->op_eeprom_config1, ret);
return ret;
}
#ifdef CONFIG_PM
static int mlx90614_power_get(struct mlx90614_data *data, bool startup)
{
unsigned long now;
int ret;
if (!data->wakeup_gpio)
return 0;
ret = pm_runtime_resume_and_get(&data->client->dev);
if (ret < 0)
return ret;
if (startup) {
now = jiffies;
if (time_before(now, data->ready_timestamp) &&
msleep_interruptible(jiffies_to_msecs(
data->ready_timestamp - now)) != 0) {
pm_runtime_put_autosuspend(&data->client->dev);
return -EINTR;
}
}
return 0;
}
static void mlx90614_power_put(struct mlx90614_data *data)
{
if (!data->wakeup_gpio)
return;
pm_runtime_mark_last_busy(&data->client->dev);
pm_runtime_put_autosuspend(&data->client->dev);
}
#else
static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)
{
return 0;
}
static inline void mlx90614_power_put(struct mlx90614_data *data)
{
}
#endif
static int mlx90614_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel, int *val,
int *val2, long mask)
{
struct mlx90614_data *data = iio_priv(indio_dev);
const struct mlx_chip_info *chip_info = data->chip_info;
u8 cmd, idx;
s32 ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (channel->channel2) {
case IIO_MOD_TEMP_AMBIENT:
cmd = chip_info->op_ram_ta;
break;
case IIO_MOD_TEMP_OBJECT:
if (chip_info->dual_channel && channel->channel)
return -EINVAL;
switch (channel->channel) {
case 0:
cmd = chip_info->op_ram_tobj1;
break;
case 1:
cmd = chip_info->op_ram_tobj2;
break;
default:
return -EINVAL;
}
break;
default:
return -EINVAL;
}
ret = mlx90614_power_get(data, true);
if (ret < 0)
return ret;
ret = i2c_smbus_read_word_data(data->client, cmd);
mlx90614_power_put(data);
if (ret < 0)
return ret;
if (ret & 0x8000)
return -EIO;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_OFFSET:
*val = MLX90614_CONST_OFFSET_DEC;
*val2 = MLX90614_CONST_OFFSET_REM;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_SCALE:
*val = MLX90614_CONST_SCALE;
return IIO_VAL_INT;
case IIO_CHAN_INFO_CALIBEMISSIVITY:
ret = mlx90614_power_get(data, false);
if (ret < 0)
return ret;
mutex_lock(&data->lock);
ret = i2c_smbus_read_word_data(data->client,
chip_info->op_eeprom_emissivity);
mutex_unlock(&data->lock);
mlx90614_power_put(data);
if (ret < 0)
return ret;
if (ret == chip_info->emissivity_max) {
*val = 1;
*val2 = 0;
} else {
*val = 0;
*val2 = ret * NSEC_PER_SEC / chip_info->emissivity_max;
}
return IIO_VAL_INT_PLUS_NANO;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
ret = mlx90614_power_get(data, false);
if (ret < 0)
return ret;
mutex_lock(&data->lock);
ret = i2c_smbus_read_word_data(data->client,
chip_info->op_eeprom_config1);
mutex_unlock(&data->lock);
mlx90614_power_put(data);
if (ret < 0)
return ret;
idx = field_get(chip_info->iir_config_mask, ret) -
chip_info->iir_valid_offset;
*val = chip_info->iir_values[idx] / 100;
*val2 = (chip_info->iir_values[idx] % 100) * 10000;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int mlx90614_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel, int val,
int val2, long mask)
{
struct mlx90614_data *data = iio_priv(indio_dev);
const struct mlx_chip_info *chip_info = data->chip_info;
s32 ret;
switch (mask) {
case IIO_CHAN_INFO_CALIBEMISSIVITY:
if (val < 0 || val2 < 0 || val > 1 || (val == 1 && val2 != 0))
return -EINVAL;
val = val * chip_info->emissivity_max +
val2 * chip_info->emissivity_max / NSEC_PER_SEC;
ret = mlx90614_power_get(data, false);
if (ret < 0)
return ret;
mutex_lock(&data->lock);
ret = mlx90614_write_word(data->client,
chip_info->op_eeprom_emissivity, val);
mutex_unlock(&data->lock);
mlx90614_power_put(data);
return ret;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
if (val < 0 || val2 < 0)
return -EINVAL;
ret = mlx90614_power_get(data, false);
if (ret < 0)
return ret;
mutex_lock(&data->lock);
ret = mlx90614_iir_search(data->client,
val * 100 + val2 / 10000);
mutex_unlock(&data->lock);
mlx90614_power_put(data);
return ret;
default:
return -EINVAL;
}
}
static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
struct iio_chan_spec const *channel,
long mask)
{
switch (mask) {
case IIO_CHAN_INFO_CALIBEMISSIVITY:
return IIO_VAL_INT_PLUS_NANO;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int mlx90614_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long mask)
{
struct mlx90614_data *data = iio_priv(indio_dev);
const struct mlx_chip_info *chip_info = data->chip_info;
switch (mask) {
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
*vals = (int *)chip_info->iir_freqs;
*type = IIO_VAL_INT_PLUS_MICRO;
*length = 2 * (ARRAY_SIZE(chip_info->iir_freqs) -
chip_info->iir_valid_offset);
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static const struct iio_chan_spec mlx90614_channels[] = {
{
.type = IIO_TEMP,
.modified = 1,
.channel2 = IIO_MOD_TEMP_AMBIENT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
BIT(IIO_CHAN_INFO_SCALE),
},
{
.type = IIO_TEMP,
.modified = 1,
.channel2 = IIO_MOD_TEMP_OBJECT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
.info_mask_separate_available =
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
BIT(IIO_CHAN_INFO_SCALE),
},
{
.type = IIO_TEMP,
.indexed = 1,
.modified = 1,
.channel = 1,
.channel2 = IIO_MOD_TEMP_OBJECT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
.info_mask_separate_available =
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
BIT(IIO_CHAN_INFO_SCALE),
},
};
static const struct iio_info mlx90614_info = {
.read_raw = mlx90614_read_raw,
.write_raw = mlx90614_write_raw,
.write_raw_get_fmt = mlx90614_write_raw_get_fmt,
.read_avail = mlx90614_read_avail,
};
#ifdef CONFIG_PM
static int mlx90614_sleep(struct mlx90614_data *data)
{
const struct mlx_chip_info *chip_info = data->chip_info;
s32 ret;
if (!data->wakeup_gpio) {
dev_dbg(&data->client->dev, "Sleep disabled");
return -ENOSYS;
}
dev_dbg(&data->client->dev, "Requesting sleep");
mutex_lock(&data->lock);
ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,
data->client->flags | I2C_CLIENT_PEC,
I2C_SMBUS_WRITE, chip_info->op_sleep,
I2C_SMBUS_BYTE, NULL);
mutex_unlock(&data->lock);
return ret;
}
static int mlx90614_wakeup(struct mlx90614_data *data)
{
const struct mlx_chip_info *chip_info = data->chip_info;
if (!data->wakeup_gpio) {
dev_dbg(&data->client->dev, "Wake-up disabled");
return -ENOSYS;
}
dev_dbg(&data->client->dev, "Requesting wake-up");
i2c_lock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
gpiod_direction_output(data->wakeup_gpio, 0);
msleep(chip_info->wakeup_delay_ms);
gpiod_direction_input(data->wakeup_gpio);
i2c_unlock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);
data->ready_timestamp = jiffies +
msecs_to_jiffies(MLX90614_TIMING_STARTUP);
i2c_smbus_read_word_data(data->client, chip_info->op_eeprom_config1);
return 0;
}
static struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
{
struct gpio_desc *gpio;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_WRITE_BYTE)) {
dev_info(&client->dev,
"i2c adapter does not support SMBUS_WRITE_BYTE, sleep disabled");
return NULL;
}
gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);
if (IS_ERR(gpio)) {
dev_warn(&client->dev,
"gpio acquisition failed with error %ld, sleep disabled",
PTR_ERR(gpio));
return NULL;
} else if (!gpio) {
dev_info(&client->dev,
"wakeup-gpio not found, sleep disabled");
}
return gpio;
}
#else
static inline int mlx90614_sleep(struct mlx90614_data *data)
{
return -ENOSYS;
}
static inline int mlx90614_wakeup(struct mlx90614_data *data)
{
return -ENOSYS;
}
static inline struct gpio_desc *mlx90614_probe_wakeup(struct i2c_client *client)
{
return NULL;
}
#endif
static int mlx90614_probe_num_ir_sensors(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct mlx90614_data *data = iio_priv(indio_dev);
const struct mlx_chip_info *chip_info = data->chip_info;
s32 ret;
if (chip_info->dual_channel)
return 0;
ret = i2c_smbus_read_word_data(client, chip_info->op_eeprom_config1);
if (ret < 0)
return ret;
return (ret & MLX90614_CONFIG_DUAL_MASK) ? 1 : 0;
}
static int mlx90614_probe(struct i2c_client *client)
{
const struct i2c_device_id *id = i2c_client_get_device_id(client);
struct iio_dev *indio_dev;
struct mlx90614_data *data;
int ret;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
return -EOPNOTSUPP;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
mutex_init(&data->lock);
data->wakeup_gpio = mlx90614_probe_wakeup(client);
data->chip_info = device_get_match_data(&client->dev);
mlx90614_wakeup(data);
indio_dev->name = id->name;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &mlx90614_info;
ret = mlx90614_probe_num_ir_sensors(client);
switch (ret) {
case 0:
dev_dbg(&client->dev, "Found single sensor");
indio_dev->channels = mlx90614_channels;
indio_dev->num_channels = 2;
break;
case 1:
dev_dbg(&client->dev, "Found dual sensor");
indio_dev->channels = mlx90614_channels;
indio_dev->num_channels = 3;
break;
default:
return ret;
}
if (data->wakeup_gpio) {
pm_runtime_set_autosuspend_delay(&client->dev,
MLX90614_AUTOSLEEP_DELAY);
pm_runtime_use_autosuspend(&client->dev);
pm_runtime_set_active(&client->dev);
pm_runtime_enable(&client->dev);
}
return iio_device_register(indio_dev);
}
static void mlx90614_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct mlx90614_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
if (data->wakeup_gpio) {
pm_runtime_disable(&client->dev);
if (!pm_runtime_status_suspended(&client->dev))
mlx90614_sleep(data);
pm_runtime_set_suspended(&client->dev);
}
}
static const struct mlx_chip_info mlx90614_chip_info = {
.op_eeprom_emissivity = MLX90614_OP_EEPROM | 0x04,
.op_eeprom_config1 = MLX90614_OP_EEPROM | 0x05,
.op_ram_ta = MLX90614_OP_RAM | 0x06,
.op_ram_tobj1 = MLX90614_OP_RAM | 0x07,
.op_ram_tobj2 = MLX90614_OP_RAM | 0x08,
.op_sleep = MLX90614_OP_SLEEP,
.dual_channel = true,
.wakeup_delay_ms = MLX90614_TIMING_WAKEUP,
.emissivity_max = 65535,
.fir_config_mask = MLX90614_CONFIG_FIR_MASK,
.iir_config_mask = MLX90614_CONFIG_IIR_MASK,
.iir_valid_offset = 0,
.iir_values = { 77, 31, 20, 15, 723, 153, 110, 86 },
.iir_freqs = {
{ 0, 150000 },
{ 0, 200000 },
{ 0, 310000 },
{ 0, 770000 },
{ 0, 860000 },
{ 1, 100000 },
{ 1, 530000 },
{ 7, 230000 }
},
};
static const struct mlx_chip_info mlx90615_chip_info = {
.op_eeprom_emissivity = MLX90615_OP_EEPROM | 0x03,
.op_eeprom_config1 = MLX90615_OP_EEPROM | 0x02,
.op_ram_ta = MLX90615_OP_RAM | 0x06,
.op_ram_tobj1 = MLX90615_OP_RAM | 0x07,
.op_ram_tobj2 = MLX90615_OP_RAM | 0x08,
.op_sleep = MLX90615_OP_SLEEP,
.dual_channel = false,
.wakeup_delay_ms = MLX90615_TIMING_WAKEUP,
.emissivity_max = 16383,
.fir_config_mask = 0,
.iir_config_mask = MLX90615_CONFIG_IIR_MASK,
.iir_valid_offset = 1,
.iir_values = { 500, 50, 30, 20, 15, 13, 10 },
.iir_freqs = {
{ 0, 100000 },
{ 0, 130000 },
{ 0, 150000 },
{ 0, 200000 },
{ 0, 300000 },
{ 0, 500000 },
{ 5, 000000 },
},
};
static const struct i2c_device_id mlx90614_id[] = {
{ "mlx90614", .driver_data = (kernel_ulong_t)&mlx90614_chip_info },
{ "mlx90615", .driver_data = (kernel_ulong_t)&mlx90615_chip_info },
{ }
};
MODULE_DEVICE_TABLE(i2c, mlx90614_id);
static const struct of_device_id mlx90614_of_match[] = {
{ .compatible = "melexis,mlx90614", .data = &mlx90614_chip_info },
{ .compatible = "melexis,mlx90615", .data = &mlx90615_chip_info },
{ }
};
MODULE_DEVICE_TABLE(of, mlx90614_of_match);
static int mlx90614_pm_suspend(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct mlx90614_data *data = iio_priv(indio_dev);
if (data->wakeup_gpio && pm_runtime_active(dev))
return mlx90614_sleep(data);
return 0;
}
static int mlx90614_pm_resume(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct mlx90614_data *data = iio_priv(indio_dev);
int err;
if (data->wakeup_gpio) {
err = mlx90614_wakeup(data);
if (err < 0)
return err;
pm_runtime_disable(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
}
return 0;
}
static int mlx90614_pm_runtime_suspend(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct mlx90614_data *data = iio_priv(indio_dev);
return mlx90614_sleep(data);
}
static int mlx90614_pm_runtime_resume(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct mlx90614_data *data = iio_priv(indio_dev);
return mlx90614_wakeup(data);
}
static const struct dev_pm_ops mlx90614_pm_ops = {
SYSTEM_SLEEP_PM_OPS(mlx90614_pm_suspend, mlx90614_pm_resume)
RUNTIME_PM_OPS(mlx90614_pm_runtime_suspend,
mlx90614_pm_runtime_resume, NULL)
};
static struct i2c_driver mlx90614_driver = {
.driver = {
.name = "mlx90614",
.of_match_table = mlx90614_of_match,
.pm = pm_ptr(&mlx90614_pm_ops),
},
.probe = mlx90614_probe,
.remove = mlx90614_remove,
.id_table = mlx90614_id,
};
module_i2c_driver(mlx90614_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
MODULE_LICENSE("GPL"