diff options
Diffstat (limited to 'drivers/iio/temperature/mcp9600.c')
| -rw-r--r-- | drivers/iio/temperature/mcp9600.c | 151 |
1 files changed, 128 insertions, 23 deletions
diff --git a/drivers/iio/temperature/mcp9600.c b/drivers/iio/temperature/mcp9600.c index 6e9108d5cf75..aa42c2b1a369 100644 --- a/drivers/iio/temperature/mcp9600.c +++ b/drivers/iio/temperature/mcp9600.c @@ -22,26 +22,31 @@ #include <linux/iio/events.h> #include <linux/iio/iio.h> +#include <dt-bindings/iio/temperature/thermocouple.h> + /* MCP9600 registers */ -#define MCP9600_HOT_JUNCTION 0x0 -#define MCP9600_COLD_JUNCTION 0x2 -#define MCP9600_STATUS 0x4 +#define MCP9600_HOT_JUNCTION 0x00 +#define MCP9600_COLD_JUNCTION 0x02 +#define MCP9600_STATUS 0x04 #define MCP9600_STATUS_ALERT(x) BIT(x) -#define MCP9600_ALERT_CFG1 0x8 +#define MCP9600_SENSOR_CFG 0x05 +#define MCP9600_SENSOR_TYPE_MASK GENMASK(6, 4) +#define MCP9600_ALERT_CFG1 0x08 #define MCP9600_ALERT_CFG(x) (MCP9600_ALERT_CFG1 + (x - 1)) #define MCP9600_ALERT_CFG_ENABLE BIT(0) #define MCP9600_ALERT_CFG_ACTIVE_HIGH BIT(2) #define MCP9600_ALERT_CFG_FALLING BIT(3) #define MCP9600_ALERT_CFG_COLD_JUNCTION BIT(4) -#define MCP9600_ALERT_HYSTERESIS1 0xc +#define MCP9600_ALERT_HYSTERESIS1 0x0c #define MCP9600_ALERT_HYSTERESIS(x) (MCP9600_ALERT_HYSTERESIS1 + (x - 1)) #define MCP9600_ALERT_LIMIT1 0x10 #define MCP9600_ALERT_LIMIT(x) (MCP9600_ALERT_LIMIT1 + (x - 1)) #define MCP9600_ALERT_LIMIT_MASK GENMASK(15, 2) -#define MCP9600_DEVICE_ID 0x20 +#define MCP9600_DEVICE_ID 0x20 /* MCP9600 device id value */ -#define MCP9600_DEVICE_ID_MCP9600 0x40 +#define MCP9600_DEVICE_ID_MCP9600 0x40 +#define MCP9600_DEVICE_ID_MCP9601 0x41 #define MCP9600_ALERT_COUNT 4 @@ -65,6 +70,30 @@ static const char * const mcp9600_alert_name[MCP9600_ALERT_COUNT] = { [MCP9600_ALERT4] = "alert4", }; +/* Map between dt-bindings enum and the chip's type value */ +static const unsigned int mcp9600_type_map[] = { + [THERMOCOUPLE_TYPE_K] = 0, + [THERMOCOUPLE_TYPE_J] = 1, + [THERMOCOUPLE_TYPE_T] = 2, + [THERMOCOUPLE_TYPE_N] = 3, + [THERMOCOUPLE_TYPE_S] = 4, + [THERMOCOUPLE_TYPE_E] = 5, + [THERMOCOUPLE_TYPE_B] = 6, + [THERMOCOUPLE_TYPE_R] = 7, +}; + +/* Map thermocouple type to a char for iio info in sysfs */ +static const int mcp9600_tc_types[] = { + [THERMOCOUPLE_TYPE_K] = 'K', + [THERMOCOUPLE_TYPE_J] = 'J', + [THERMOCOUPLE_TYPE_T] = 'T', + [THERMOCOUPLE_TYPE_N] = 'N', + [THERMOCOUPLE_TYPE_S] = 'S', + [THERMOCOUPLE_TYPE_E] = 'E', + [THERMOCOUPLE_TYPE_B] = 'B', + [THERMOCOUPLE_TYPE_R] = 'R', +}; + static const struct iio_event_spec mcp9600_events[] = { { .type = IIO_EV_TYPE_THRESH, @@ -82,12 +111,41 @@ static const struct iio_event_spec mcp9600_events[] = { }, }; +struct mcp_chip_info { + u8 chip_id; + const char *chip_name; +}; + +struct mcp9600_data { + struct i2c_client *client; + u32 thermocouple_type; +}; + +static int mcp9600_config(struct mcp9600_data *data) +{ + struct i2c_client *client = data->client; + int ret; + u8 cfg; + + cfg = FIELD_PREP(MCP9600_SENSOR_TYPE_MASK, + mcp9600_type_map[data->thermocouple_type]); + + ret = i2c_smbus_write_byte_data(client, MCP9600_SENSOR_CFG, cfg); + if (ret < 0) { + dev_err(&client->dev, "Failed to set sensor configuration\n"); + return ret; + } + + return 0; +} + #define MCP9600_CHANNELS(hj_num_ev, hj_ev_spec_off, cj_num_ev, cj_ev_spec_off) \ { \ { \ .type = IIO_TEMP, \ .address = MCP9600_HOT_JUNCTION, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_THERMOCOUPLE_TYPE) | \ BIT(IIO_CHAN_INFO_SCALE), \ .event_spec = &mcp9600_events[hj_ev_spec_off], \ .num_event_specs = hj_num_ev, \ @@ -123,10 +181,6 @@ static const struct iio_chan_spec mcp9600_channels[][2] = { MCP9600_CHANNELS(2, 0, 2, 0), /* Alerts: 1 2 3 4 */ }; -struct mcp9600_data { - struct i2c_client *client; -}; - static int mcp9600_read(struct mcp9600_data *data, struct iio_chan_spec const *chan, int *val) { @@ -159,6 +213,9 @@ static int mcp9600_read_raw(struct iio_dev *indio_dev, *val = 62; *val2 = 500000; return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_THERMOCOUPLE_TYPE: + *val = mcp9600_tc_types[data->thermocouple_type]; + return IIO_VAL_CHAR; default: return -EINVAL; } @@ -416,45 +473,93 @@ static int mcp9600_probe_alerts(struct iio_dev *indio_dev) static int mcp9600_probe(struct i2c_client *client) { + struct device *dev = &client->dev; + const struct mcp_chip_info *chip_info; struct iio_dev *indio_dev; struct mcp9600_data *data; - int ret, ch_sel; + int ch_sel, dev_id, ret; + + chip_info = i2c_get_match_data(client); + if (!chip_info) + return dev_err_probe(dev, -ENODEV, + "No chip-info found for device\n"); + + dev_id = i2c_smbus_read_byte_data(client, MCP9600_DEVICE_ID); + if (dev_id < 0) + return dev_err_probe(dev, dev_id, "Failed to read device ID\n"); + + switch (dev_id) { + case MCP9600_DEVICE_ID_MCP9600: + case MCP9600_DEVICE_ID_MCP9601: + if (dev_id != chip_info->chip_id) + dev_warn(dev, + "Expected id %02x, but device responded with %02x\n", + chip_info->chip_id, dev_id); + break; - ret = i2c_smbus_read_byte_data(client, MCP9600_DEVICE_ID); - if (ret < 0) - return dev_err_probe(&client->dev, ret, "Failed to read device ID\n"); - if (ret != MCP9600_DEVICE_ID_MCP9600) - dev_warn(&client->dev, "Expected ID %x, got %x\n", - MCP9600_DEVICE_ID_MCP9600, ret); + default: + dev_warn(dev, "Unknown id %x, using %x\n", dev_id, + chip_info->chip_id); + } - indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); if (!indio_dev) return -ENOMEM; data = iio_priv(indio_dev); data->client = client; + /* Accept type from dt with default of Type-K. */ + data->thermocouple_type = THERMOCOUPLE_TYPE_K; + ret = device_property_read_u32(dev, "thermocouple-type", + &data->thermocouple_type); + if (ret && ret != -EINVAL) + return dev_err_probe(dev, ret, + "Error reading thermocouple-type property\n"); + + if (data->thermocouple_type >= ARRAY_SIZE(mcp9600_type_map)) + return dev_err_probe(dev, -EINVAL, + "Invalid thermocouple-type property %u.\n", + data->thermocouple_type); + + /* Set initial config. */ + ret = mcp9600_config(data); + if (ret) + return ret; + ch_sel = mcp9600_probe_alerts(indio_dev); if (ch_sel < 0) return ch_sel; indio_dev->info = &mcp9600_info; - indio_dev->name = "mcp9600"; + indio_dev->name = chip_info->chip_name; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->channels = mcp9600_channels[ch_sel]; indio_dev->num_channels = ARRAY_SIZE(mcp9600_channels[ch_sel]); - return devm_iio_device_register(&client->dev, indio_dev); + return devm_iio_device_register(dev, indio_dev); } +static const struct mcp_chip_info mcp9600_chip_info = { + .chip_id = MCP9600_DEVICE_ID_MCP9600, + .chip_name = "mcp9600", +}; + +static const struct mcp_chip_info mcp9601_chip_info = { + .chip_id = MCP9600_DEVICE_ID_MCP9601, + .chip_name = "mcp9601", +}; + static const struct i2c_device_id mcp9600_id[] = { - { "mcp9600" }, + { "mcp9600", .driver_data = (kernel_ulong_t)&mcp9600_chip_info }, + { "mcp9601", .driver_data = (kernel_ulong_t)&mcp9601_chip_info }, { } }; MODULE_DEVICE_TABLE(i2c, mcp9600_id); static const struct of_device_id mcp9600_of_match[] = { - { .compatible = "microchip,mcp9600" }, + { .compatible = "microchip,mcp9600", .data = &mcp9600_chip_info }, + { .compatible = "microchip,mcp9601", .data = &mcp9601_chip_info }, { } }; MODULE_DEVICE_TABLE(of, mcp9600_of_match); |