feat(brightness): add conversion for linear values to a 2.4 Gamma curve and multiple keyboards through D-Bus

docs/modules/Brightness.md

@@ -5,15 +5,16 @@ Allows to change the respective value via scrolling.
 
 > Type: `brightness`
 
-| Name                   | Type                    | Default         | Profile? | Description                                                                                                                                                                                       |
-|------------------------|-------------------------|-----------------|----------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
-| `format`               | `string`                | `{percentage}%` | Yes      | Format string to use for the widget button label.                                                                                                                                                 |
-| `icon_label`           | `string`                | `null`          | Yes      | Icon to show alongside the label. Supports [image](images) icons.                                                                                                                                 |
-| `mode.type`            | `systemd` or `keyboard` | `systemd`       | No       | The data backend of the brightness module, this can be either the KdbBrightness dbus which is good for keyboard data, or the more general login1 dbus in combination with /sys/class/{subsystem}. |
-| `mode.subsystem`       | `backlight` or `leds`   | `backlight`     | No       | The name of the subsystem use on the filesystem.                                                                                                                                                  |
-| `mode.name`            | `string` or `null`      | `null`          | No       | When set, using the specific directory, within /sys/class/{subsystem} . If null the module will try to find a reasonable default.                                                                 |
-| `smooth_scroll_speed`  | `float`                 | `1.0`           | No       | Controls how fast the brightness is changed, e.g. in case touchpad scrolling is used. Negative values swap the scroll direction.                                                                  |
-| `use_default_profiles` | `boolean`               | `true`          | No       | Whether default profiles should be used.                                                                                                                                                          |
+| Name                   | Type                    | Default               | Profile?    | Description                                                                                                                                                                                       |
+|------------------------|-------------------------|-----------------------|-------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `format`               | `string`                | `{percentage}%`       | Yes         | Format string to use for the widget button label.                                                                                                                                                 |
+| `icon_label`           | `string`                | `null`                | Yes         | Icon to show alongside the label. Supports [image](images) icons.                                                                                                                                 |
+| `mode.type`            | `systemd` or `keyboard` | `systemd`             | No          | The data backend of the brightness module, this can be either the KdbBrightness dbus which is good for keyboard data, or the more general login1 dbus in combination with /sys/class/{subsystem}. |
+| `mode.subsystem`       | `backlight` or `leds`   | `backlight`           | No          | The name of the subsystem use on the filesystem.                                                                                                                                                  |
+| `mode.name`            | `string` or `null`      | `null`                | No          | When set, using the specific directory, within /sys/class/{subsystem} . If null the module will try to find a reasonable default.                                                                 |
+| `scale`                | `automatic`, `linear`, `gamma2_2`, or `gamma2_4`| `automatic` | No | Sets the scaling strategy for converting brightness values into percentages. Automatic will try to fit linear values into a Gamma 2.4 transfert function to better match our perception of light. You can force other conversion by selecting them.
+| `smooth_scroll_speed`  | `float`                 | `1.0`                 | No          | Controls how fast the brightness is changed, e.g. in case touchpad scrolling is used. Negative values swap the scroll direction.                                                                  |
+| `use_default_profiles` | `boolean`               | `true`                | No          | Whether default profiles should be used.                                                                                                                                                          |
 
 Information on the profiles system can be found [here](profiles).
 

src/clients/brightness/dbus_keyboard.rs

@@ -3,7 +3,7 @@ use zbus::proxy;
 #[proxy(
     interface = "org.freedesktop.UPower.KbdBacklight",
     default_service = "org.freedesktop.UPower",
-    default_path = "/org/freedesktop/UPower/KbdBacklight"
+    assume_defaults = false
 )]
 pub trait KbdBacklight {
     /// GetMaxBrightness method

src/clients/brightness/fs_reader.rs

@@ -9,6 +9,18 @@ pub enum ReadParseError {
     Parse(std::num::ParseIntError),
 }
 
+impl From<std::io::Error> for ReadParseError {
+    fn from(value: std::io::Error) -> Self {
+        Self::Read(value)
+    }
+}
+
+impl From<std::num::ParseIntError> for ReadParseError {
+    fn from(value: std::num::ParseIntError) -> Self {
+        Self::Parse(value)
+    }
+}
+
 impl fmt::Display for ReadParseError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
@@ -22,27 +34,52 @@ impl std::error::Error for ReadParseError {}
 
 const SYS_PATH: &str = "/sys/class";
 
-pub fn brightness(subsystem: &str, name: &str) -> Result<i32, ReadParseError> {
+/// Build path from `subsystem` and `name`.
+///
+/// The path built has [SYS_PATH] as a prefix.
+fn build_path(subsystem: &str, name: &str) -> PathBuf {
     let mut path = PathBuf::from(SYS_PATH);
     path.push(subsystem);
     path.push(name);
-    path.push("brightness");
-    let s = fs::read_to_string(path).map_err(ReadParseError::Read)?;
-    let value = s.trim().parse::<i32>().map_err(ReadParseError::Parse)?;
-    Ok(value)
+    path
 }
 
-pub fn max_brightness(subsystem: &str, name: &str) -> Result<i32, ReadParseError> {
-    let mut path = PathBuf::from(SYS_PATH);
-    path.push(subsystem);
-    path.push(name);
-    path.push("max_brightness");
-    let s = fs::read_to_string(path).map_err(ReadParseError::Read)?;
-    let value = s.trim().parse::<i32>().map_err(ReadParseError::Parse)?;
-    Ok(value)
+/// Read an [i32] for a specific `attribute`.
+///
+/// Select within [SYS_PATH] the `subsystem` and the `driver` for the `attribute` you want to read an [i32] from.
+fn read_i32_from_file(
+    subsystem: &str,
+    driver: &str,
+    attribute: &str,
+) -> Result<i32, ReadParseError> {
+    let mut path = build_path(subsystem, driver);
+    path.push(attribute);
+    let s = fs::read_to_string(path)?;
+    Ok(s.trim().parse::<i32>()?)
+}
+
+/// Get the `brightness` attribute from the `subsystem` and `driver` within [SYS_PATH].
+pub fn brightness(subsystem: &str, driver: &str) -> Result<i32, ReadParseError> {
+    read_i32_from_file(subsystem, driver, "brightness")
+}
+
+/// Get the `max_brightness` attribute from the `subsystem` and `driver` within [SYS_PATH].
+pub fn max_brightness(subsystem: &str, driver: &str) -> Result<i32, ReadParseError> {
+    read_i32_from_file(subsystem, driver, "max_brightness")
+}
+
+/// Get the scaling of the brightness.
+///
+/// Possible values are:
+///     - "unknown"
+///     - "linear"
+pub(super) fn scaling(subsystem: &str, driver: &str) -> Result<Box<str>, ReadParseError> {
+    let mut path = build_path(subsystem, driver);
+    path.push("scale");
+    Ok(Box::from(fs::read_to_string(path)?.as_str()))
 }
 
-pub(super) fn available_resource_names(subsystem: &str) -> Vec<String> {
+pub(super) fn available_resource_names(subsystem: &str) -> Vec<Box<str>> {
     let mut path = PathBuf::from(SYS_PATH);
     path.push(subsystem);
 
@@ -53,15 +90,15 @@ pub(super) fn available_resource_names(subsystem: &str) -> Vec<String> {
             if path.is_dir()
                 && let Some(name) = entry.file_name().to_str()
             {
-                resource_names.push(name.to_string());
+                resource_names.push(Box::from(name));
             }
         }
     }
     resource_names.sort();
     resource_names
 }
 
-pub fn default_resource_name(subsystem: &str) -> Option<String> {
+pub fn default_resource_name(subsystem: &str) -> Option<Box<str>> {
     let possible_files = available_resource_names(subsystem);
 
     match subsystem {
@@ -82,8 +119,8 @@ pub fn default_resource_name(subsystem: &str) -> Option<String> {
 
             TO_CHECK
                 .iter()
-                .find(|item| possible_files.iter().any(|v| v == **item))
-                .map(ToString::to_string)
+                .find(|&item| possible_files.iter().any(|v| **v == **item))
+                .map(|s| Box::from(*s))
         }
         "leds" => {
             // almost all leds have the same postfix

src/clients/brightness/ironvar.rs

@@ -1,6 +1,13 @@
 use super::{brightness, fs_reader::available_resource_names, max_brightness};
-use crate::await_sync;
-use std::sync::Arc;
+use crate::{
+    await_sync,
+    clients::brightness::{BrightnessDevice, BrightnessTypeProperties},
+    lock,
+};
+use std::{
+    collections::HashMap,
+    sync::{Arc, Mutex},
+};
 
 const KDB_NAMESPACE: &str = "kbd_backlight";
 const KDB_KEY_MAX_BRIGHTNESS: &str = "max";
@@ -10,8 +17,12 @@ const BACKLIGHT_MAX_NAMESPACE: &str = "backlight_max";
 const LEDS_CURRENT_NAMESPACE: &str = "leds_current";
 const LEDS_MAX_NAMESPACE: &str = "leds_max";
 
-#[derive(Debug)]
 pub(super) struct KbdBacklight {
+    keyboards: Arc<Mutex<HashMap<Box<str>, BrightnessDevice>>>,
+}
+
+#[derive(Debug)]
+pub(super) struct KbdBacklightDevice {
     keyboard: Arc<super::KbdBacklightProxy<'static>>,
 }
 
@@ -28,6 +39,40 @@ enum Property {
 }
 
 impl crate::ironvar::Namespace for KbdBacklight {
+    fn get(&self, _: &str) -> Option<String> {
+        None
+    }
+
+    fn list(&self) -> Vec<String> {
+        Vec::new()
+    }
+
+    fn namespaces(&self) -> Vec<String> {
+        let mut namespaces = Vec::new();
+
+        let devices = lock!(self.keyboards);
+
+        for (key, values) in devices.iter() {
+            if matches!(values.properties, BrightnessTypeProperties::Kbd { .. }) {
+                namespaces.push(key.to_string());
+            }
+        }
+
+        namespaces
+    }
+
+    fn get_namespace(&self, key: &str) -> Option<crate::ironvar::NamespaceTrait> {
+        let devices = lock!(self.keyboards);
+        match &devices.get(key)?.properties {
+            BrightnessTypeProperties::Kbd { proxy, .. } => Some(Arc::new(KbdBacklightDevice {
+                keyboard: Arc::new(proxy.clone()),
+            })),
+            BrightnessTypeProperties::SysFs { .. } => None,
+        }
+    }
+}
+
+impl crate::ironvar::Namespace for KbdBacklightDevice {
     fn get(&self, key: &str) -> Option<String> {
         match key {
             KDB_KEY_MAX_BRIGHTNESS => await_sync(self.keyboard.get_max_brightness())
@@ -49,7 +94,7 @@ impl crate::ironvar::Namespace for KbdBacklight {
     }
 
     fn namespaces(&self) -> Vec<String> {
-        vec![]
+        Vec::new()
     }
 
     fn get_namespace(&self, _key: &str) -> Option<crate::ironvar::NamespaceTrait> {
@@ -69,6 +114,9 @@ impl crate::ironvar::Namespace for FsBacklight {
 
     fn list(&self) -> Vec<String> {
         available_resource_names(&self.subsystem)
+            .iter()
+            .map(|s| s.to_string())
+            .collect()
     }
 
     fn namespaces(&self) -> Vec<String> {
@@ -101,9 +149,12 @@ impl crate::ironvar::Namespace for super::Client {
 
     fn get_namespace(&self, key: &str) -> Option<crate::ironvar::NamespaceTrait> {
         match key {
-            KDB_NAMESPACE => Some(Arc::new(KbdBacklight {
-                keyboard: self.keyboard.clone(),
-            })),
+            KDB_NAMESPACE => match self {
+                super::Client::Stopped { .. } => None,
+                super::Client::Started { devices, .. } => Some(Arc::new(KbdBacklight {
+                    keyboards: devices.clone(),
+                })),
+            },
             BACKLIGHT_CURRENT_NAMESPACE => Some(Arc::new(FsBacklight {
                 subsystem: "backlight".to_string(),
                 property: Property::Brightness,