diff options
Diffstat (limited to 'drivers/hwmon/tmp421.c')
-rw-r--r-- | drivers/hwmon/tmp421.c | 186 |
1 files changed, 170 insertions, 16 deletions
diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c index b963a369c5ab..1fd8d41d90c8 100644 --- a/drivers/hwmon/tmp421.c +++ b/drivers/hwmon/tmp421.c @@ -29,15 +29,20 @@ static const unsigned short normal_i2c[] = { 0x2a, 0x4c, 0x4d, 0x4e, 0x4f, enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 }; +#define MAX_CHANNELS 4 /* The TMP421 registers */ #define TMP421_STATUS_REG 0x08 #define TMP421_CONFIG_REG_1 0x09 +#define TMP421_CONFIG_REG_2 0x0A +#define TMP421_CONFIG_REG_REN(x) (BIT(3 + (x))) +#define TMP421_CONFIG_REG_REN_MASK GENMASK(6, 3) #define TMP421_CONVERSION_RATE_REG 0x0B +#define TMP421_N_FACTOR_REG_1 0x21 #define TMP421_MANUFACTURER_ID_REG 0xFE #define TMP421_DEVICE_ID_REG 0xFF -static const u8 TMP421_TEMP_MSB[4] = { 0x00, 0x01, 0x02, 0x03 }; -static const u8 TMP421_TEMP_LSB[4] = { 0x10, 0x11, 0x12, 0x13 }; +static const u8 TMP421_TEMP_MSB[MAX_CHANNELS] = { 0x00, 0x01, 0x02, 0x03 }; +static const u8 TMP421_TEMP_LSB[MAX_CHANNELS] = { 0x10, 0x11, 0x12, 0x13 }; /* Flags */ #define TMP421_CONFIG_SHUTDOWN 0x40 @@ -86,18 +91,24 @@ static const struct of_device_id __maybe_unused tmp421_of_match[] = { }; MODULE_DEVICE_TABLE(of, tmp421_of_match); +struct tmp421_channel { + const char *label; + bool enabled; + s16 temp; +}; + struct tmp421_data { struct i2c_client *client; struct mutex update_lock; - u32 temp_config[5]; + u32 temp_config[MAX_CHANNELS + 1]; struct hwmon_channel_info temp_info; const struct hwmon_channel_info *info[2]; struct hwmon_chip_info chip; - char valid; + bool valid; unsigned long last_updated; unsigned long channels; u8 config; - s16 temp[4]; + struct tmp421_channel channel[MAX_CHANNELS]; }; static int temp_from_raw(u16 reg, bool extended) @@ -132,28 +143,56 @@ static int tmp421_update_device(struct tmp421_data *data) ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_MSB[i]); if (ret < 0) goto exit; - data->temp[i] = ret << 8; + data->channel[i].temp = ret << 8; ret = i2c_smbus_read_byte_data(client, TMP421_TEMP_LSB[i]); if (ret < 0) goto exit; - data->temp[i] |= ret; + data->channel[i].temp |= ret; } data->last_updated = jiffies; - data->valid = 1; + data->valid = true; } exit: mutex_unlock(&data->update_lock); if (ret < 0) { - data->valid = 0; + data->valid = false; return ret; } return 0; } +static int tmp421_enable_channels(struct tmp421_data *data) +{ + int err; + struct i2c_client *client = data->client; + struct device *dev = &client->dev; + int old = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_2); + int new, i; + + if (old < 0) { + dev_err(dev, "error reading register, can't disable channels\n"); + return old; + } + + new = old & ~TMP421_CONFIG_REG_REN_MASK; + for (i = 0; i < data->channels; i++) + if (data->channel[i].enabled) + new |= TMP421_CONFIG_REG_REN(i); + + if (new == old) + return 0; + + err = i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_2, new); + if (err < 0) + dev_err(dev, "error writing register, can't disable channels\n"); + + return err; +} + static int tmp421_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long *val) { @@ -166,15 +205,22 @@ static int tmp421_read(struct device *dev, enum hwmon_sensor_types type, switch (attr) { case hwmon_temp_input: - *val = temp_from_raw(tmp421->temp[channel], + if (!tmp421->channel[channel].enabled) + return -ENODATA; + *val = temp_from_raw(tmp421->channel[channel].temp, tmp421->config & TMP421_CONFIG_RANGE); return 0; case hwmon_temp_fault: + if (!tmp421->channel[channel].enabled) + return -ENODATA; /* * Any of OPEN or /PVLD bits indicate a hardware mulfunction * and the conversion result may be incorrect */ - *val = !!(tmp421->temp[channel] & 0x03); + *val = !!(tmp421->channel[channel].temp & 0x03); + return 0; + case hwmon_temp_enable: + *val = tmp421->channel[channel].enabled; return 0; default: return -EOPNOTSUPP; @@ -182,6 +228,34 @@ static int tmp421_read(struct device *dev, enum hwmon_sensor_types type, } +static int tmp421_read_string(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, const char **str) +{ + struct tmp421_data *data = dev_get_drvdata(dev); + + *str = data->channel[channel].label; + + return 0; +} + +static int tmp421_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + struct tmp421_data *data = dev_get_drvdata(dev); + int ret; + + switch (attr) { + case hwmon_temp_enable: + data->channel[channel].enabled = val; + ret = tmp421_enable_channels(data); + break; + default: + ret = -EOPNOTSUPP; + } + + return ret; +} + static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, int channel) { @@ -189,14 +263,19 @@ static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type, case hwmon_temp_fault: case hwmon_temp_input: return 0444; + case hwmon_temp_label: + return 0444; + case hwmon_temp_enable: + return 0644; default: return 0; } } -static int tmp421_init_client(struct i2c_client *client) +static int tmp421_init_client(struct tmp421_data *data) { int config, config_orig; + struct i2c_client *client = data->client; /* Set the conversion rate to 2 Hz */ i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05); @@ -217,7 +296,7 @@ static int tmp421_init_client(struct i2c_client *client) i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config); } - return 0; + return tmp421_enable_channels(data); } static int tmp421_detect(struct i2c_client *client, @@ -281,9 +360,78 @@ static int tmp421_detect(struct i2c_client *client, return 0; } +static int tmp421_probe_child_from_dt(struct i2c_client *client, + struct device_node *child, + struct tmp421_data *data) + +{ + struct device *dev = &client->dev; + u32 i; + s32 val; + int err; + + err = of_property_read_u32(child, "reg", &i); + if (err) { + dev_err(dev, "missing reg property of %pOFn\n", child); + return err; + } + + if (i >= data->channels) { + dev_err(dev, "invalid reg %d of %pOFn\n", i, child); + return -EINVAL; + } + + of_property_read_string(child, "label", &data->channel[i].label); + if (data->channel[i].label) + data->temp_config[i] |= HWMON_T_LABEL; + + data->channel[i].enabled = of_device_is_available(child); + + err = of_property_read_s32(child, "ti,n-factor", &val); + if (!err) { + if (i == 0) { + dev_err(dev, "n-factor can't be set for internal channel\n"); + return -EINVAL; + } + + if (val > 127 || val < -128) { + dev_err(dev, "n-factor for channel %d invalid (%d)\n", + i, val); + return -EINVAL; + } + i2c_smbus_write_byte_data(client, TMP421_N_FACTOR_REG_1 + i - 1, + val); + } + + return 0; +} + +static int tmp421_probe_from_dt(struct i2c_client *client, struct tmp421_data *data) +{ + struct device *dev = &client->dev; + const struct device_node *np = dev->of_node; + struct device_node *child; + int err; + + for_each_child_of_node(np, child) { + if (strcmp(child->name, "channel")) + continue; + + err = tmp421_probe_child_from_dt(client, child, data); + if (err) { + of_node_put(child); + return err; + } + } + + return 0; +} + static const struct hwmon_ops tmp421_ops = { .is_visible = tmp421_is_visible, .read = tmp421_read, + .read_string = tmp421_read_string, + .write = tmp421_write, }; static int tmp421_probe(struct i2c_client *client) @@ -305,12 +453,18 @@ static int tmp421_probe(struct i2c_client *client) data->channels = i2c_match_id(tmp421_id, client)->driver_data; data->client = client; - err = tmp421_init_client(client); + for (i = 0; i < data->channels; i++) { + data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_ENABLE; + data->channel[i].enabled = true; + } + + err = tmp421_probe_from_dt(client, data); if (err) return err; - for (i = 0; i < data->channels; i++) - data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT; + err = tmp421_init_client(data); + if (err) + return err; data->chip.ops = &tmp421_ops; data->chip.info = data->info; |