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path: root/drivers/hwmon/tmp421.c
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Diffstat (limited to 'drivers/hwmon/tmp421.c')
-rw-r--r--drivers/hwmon/tmp421.c186
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;