diff --git a/drivers/iio/humidity/si7020.c b/drivers/iio/humidity/si7020.c index d34a915e3d4a..ff2dba50c0a5 100644 --- a/drivers/iio/humidity/si7020.c +++ b/drivers/iio/humidity/si7020.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include @@ -33,17 +34,38 @@ #define SI7020CMD_TEMP_HOLD 0xE3 /* Software Reset */ #define SI7020CMD_RESET 0xFE +#define SI7020CMD_USR_WRITE 0xE6 +/* "Heater Enabled" bit in the User Register */ +#define SI7020_USR_HEATER_EN BIT(2) +#define SI7020CMD_HEATER_WRITE 0x51 +/* Heater current configuration bits */ +#define SI7020_HEATER_VAL GENMASK(3, 0) + +struct si7020_data { + struct i2c_client *client; + /* Lock for cached register values */ + struct mutex lock; + u8 user_reg; + u8 heater_reg; +}; + +static const int si7020_heater_vals[] = { 0, 1, 0xF }; static int si7020_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { - struct i2c_client **client = iio_priv(indio_dev); + struct si7020_data *data = iio_priv(indio_dev); int ret; switch (mask) { case IIO_CHAN_INFO_RAW: - ret = i2c_smbus_read_word_swapped(*client, + if (chan->type == IIO_CURRENT) { + *val = data->heater_reg; + return IIO_VAL_INT; + } + + ret = i2c_smbus_read_word_swapped(data->client, chan->type == IIO_TEMP ? SI7020CMD_TEMP_HOLD : SI7020CMD_RH_HOLD); @@ -96,17 +118,118 @@ static const struct iio_chan_spec si7020_channels[] = { .type = IIO_TEMP, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET), + }, + { + .type = IIO_CURRENT, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW), + .extend_name = "heater", } }; +static int si7020_update_reg(struct si7020_data *data, + u8 *reg, u8 cmd, u8 mask, u8 val) +{ + u8 new = (*reg & ~mask) | val; + int ret; + + ret = i2c_smbus_write_byte_data(data->client, cmd, new); + if (ret) + return ret; + + *reg = new; + + return 0; +} + +static int si7020_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct si7020_data *data = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (chan->type != IIO_CURRENT || val2 != 0 || + val < si7020_heater_vals[0] || val > si7020_heater_vals[2]) + return -EINVAL; + + scoped_guard(mutex, &data->lock) + ret = si7020_update_reg(data, &data->heater_reg, + SI7020CMD_HEATER_WRITE, SI7020_HEATER_VAL, val); + return ret; + default: + return -EINVAL; + } +} + +static int si7020_read_available(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, + int *type, int *length, long mask) +{ + if (mask != IIO_CHAN_INFO_RAW || chan->type != IIO_CURRENT) + return -EINVAL; + + *vals = si7020_heater_vals; + *type = IIO_VAL_INT; + + return IIO_AVAIL_RANGE; +} + +static ssize_t si7020_show_heater_en(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct si7020_data *data = iio_priv(indio_dev); + + return sysfs_emit(buf, "%d\n", !!(data->user_reg & SI7020_USR_HEATER_EN)); +} + +static ssize_t si7020_store_heater_en(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_dev *indio_dev = dev_to_iio_dev(dev); + struct si7020_data *data = iio_priv(indio_dev); + int ret; + bool val; + + ret = kstrtobool(buf, &val); + if (ret) + return ret; + + scoped_guard(mutex, &data->lock) + ret = si7020_update_reg(data, &data->user_reg, SI7020CMD_USR_WRITE, + SI7020_USR_HEATER_EN, val ? SI7020_USR_HEATER_EN : 0); + + return ret < 0 ? ret : len; +} + +static IIO_DEVICE_ATTR(heater_enable, 0644, + si7020_show_heater_en, si7020_store_heater_en, 0); + +static struct attribute *si7020_attributes[] = { + &iio_dev_attr_heater_enable.dev_attr.attr, + NULL +}; + +static const struct attribute_group si7020_attribute_group = { + .attrs = si7020_attributes, +}; + static const struct iio_info si7020_info = { .read_raw = si7020_read_raw, + .write_raw = si7020_write_raw, + .read_avail = si7020_read_available, + .attrs = &si7020_attribute_group, }; static int si7020_probe(struct i2c_client *client) { struct iio_dev *indio_dev; - struct i2c_client **data; + struct si7020_data *data; int ret; if (!i2c_check_functionality(client->adapter, @@ -126,7 +249,9 @@ static int si7020_probe(struct i2c_client *client) return -ENOMEM; data = iio_priv(indio_dev); - *data = client; + i2c_set_clientdata(client, indio_dev); + data->client = client; + mutex_init(&data->lock); indio_dev->name = dev_name(&client->dev); indio_dev->modes = INDIO_DIRECT_MODE; @@ -134,6 +259,10 @@ static int si7020_probe(struct i2c_client *client) indio_dev->channels = si7020_channels; indio_dev->num_channels = ARRAY_SIZE(si7020_channels); + /* All the "reserved" bits in the User Register are 1s by default */ + data->user_reg = 0x3A; + data->heater_reg = 0x0; + return devm_iio_device_register(&client->dev, indio_dev); }