diff mbox series

[v5,2/9] hwmon: (tmp421) add support for defining labels from DT

Message ID dab0fda6ac0e8d7f163c3762a7fb1e595a4d8159.1634206677.git.krzysztof.adamski@nokia.com (mailing list archive)
State Accepted
Headers show
Series Add per channel properies support in tmp421 | expand

Commit Message

Krzysztof Adamski Oct. 14, 2021, 1 p.m. UTC
tmp42x is a multichannel temperature sensor with several external
channels. Since those channels can be used to connect diodes placed
anywhere in the system, their meaning will vary depending on the
project. For this case, the hwmon framework has an idea of labels which
allows us to assign the meaning to each channel.

The similar concept is already implemented in ina3221 - the label for
each channel can be defined via device tree. See commit a9e9dd9c6de5
("hwmon: (ina3221) Read channel input source info from DT")

This patch adds support for similar feature to tmp421.

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
---
  drivers/hwmon/tmp421.c | 61 ++++++++++++++++++++++++++++++++++++++++++
  1 file changed, 61 insertions(+)

Comments

Guenter Roeck Oct. 15, 2021, 10:45 p.m. UTC | #1
On Thu, Oct 14, 2021 at 03:00:49PM +0200, Krzysztof Adamski wrote:
> tmp42x is a multichannel temperature sensor with several external
> channels. Since those channels can be used to connect diodes placed
> anywhere in the system, their meaning will vary depending on the
> project. For this case, the hwmon framework has an idea of labels which
> allows us to assign the meaning to each channel.
> 
> The similar concept is already implemented in ina3221 - the label for
> each channel can be defined via device tree. See commit a9e9dd9c6de5
> ("hwmon: (ina3221) Read channel input source info from DT")
> 
> This patch adds support for similar feature to tmp421.
> 
> Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
> ---
>   drivers/hwmon/tmp421.c | 61 ++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 61 insertions(+)
> 
> diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c
> index 707310d616a4..89346ca6c9a9 100644
> --- a/drivers/hwmon/tmp421.c
> +++ b/drivers/hwmon/tmp421.c
> @@ -88,6 +88,7 @@ static const struct of_device_id __maybe_unused tmp421_of_match[] = {
>   MODULE_DEVICE_TABLE(of, tmp421_of_match);
>   
>   struct tmp421_channel {
> +	const char *label;
>   	s16 temp;
>   };

git reports this patch as corrupted and claims it was hand-edited.
Looking into it, there is an extra space in unchanged lines of code.
Indeed, it applies cleanly after replacing douple spaces at the beginning
of each line with a single space.

No idea how that happened, but please be careful whend sending patches.

Applied.

Guenter
diff mbox series

Patch

diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c
index 707310d616a4..89346ca6c9a9 100644
--- a/drivers/hwmon/tmp421.c
+++ b/drivers/hwmon/tmp421.c
@@ -88,6 +88,7 @@  static const struct of_device_id __maybe_unused tmp421_of_match[] = {
  MODULE_DEVICE_TABLE(of, tmp421_of_match);
  
  struct tmp421_channel {
+	const char *label;
  	s16 temp;
  };
  
@@ -187,6 +188,16 @@  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 umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type,
  				 u32 attr, int channel)
  {
@@ -194,6 +205,8 @@  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;
  	default:
  		return 0;
  	}
@@ -286,9 +299,53 @@  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;
+	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;
+
+	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) {
+		err = tmp421_probe_child_from_dt(client, child, data);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
  static const struct hwmon_ops tmp421_ops = {
  	.is_visible = tmp421_is_visible,
  	.read = tmp421_read,
+	.read_string = tmp421_read_string,
  };
  
  static int tmp421_probe(struct i2c_client *client)
@@ -317,6 +374,10 @@  static int tmp421_probe(struct i2c_client *client)
  	for (i = 0; i < data->channels; i++)
  		data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT;
  
+	err = tmp421_probe_from_dt(client, data);
+	if (err)
+		return err;
+
  	data->chip.ops = &tmp421_ops;
  	data->chip.info = data->info;