Allow backlight device to be specified

config.json

@@ -23,7 +23,7 @@
 						},{
 							"margin": {
 								"margins": [0,0,0,8],
-								"widget": {"backlight": {"font_size": 24.0,"length": 600}}
+								"widget": {"backlight": {"device": "intel_backlight", "font_size": 24.0,"length": 600}}
 							}
 						},{
 							"margin": {

config.yaml

@@ -30,6 +30,7 @@ widget:
                     margins: [0, 0, 0, 8]
                     widget:
                       backlight:
+                        device: "intel_backlight"
                         font_size: 24.0
                         length: 600
                 - margin:

src/config.rs

@@ -45,6 +45,8 @@ pub enum Widget {
         length: u32,
     },
     Backlight {
+        #[serde(default)]
+        device: String,
         font_size: f32,
         length: u32,
     },
@@ -121,8 +123,13 @@ impl Widget {
                     Err(_) => None,
                 }
             }
-            Widget::Backlight { font_size, length } => {
-                match widgets::backlight::Backlight::new(font_size, length) {
+            Widget::Backlight { device, font_size, length } => {
+                let d = if device == "" {
+                    "intel_backlight"
+                } else {
+                    &device
+                };
+                match widgets::backlight::Backlight::new(d, font_size, length) {
                     Ok(w) => Some(w),
                     Err(_) => None,
                 }
@@ -192,6 +199,7 @@ impl Default for Config {
                             Box::new(Widget::Margin {
                                 margins: (0, 0, 0, 8),
                                 widget: Box::new(Widget::Backlight {
+                                    device: "intel_backlight".to_string(),
                                     font_size: 24.0,
                                     length: 600,
                                 }),

src/widgets/backlight.rs

@@ -71,18 +71,9 @@ impl Backlight {
         Ok(())
     }
 
-    pub fn new(font_size: f32, length: u32) -> Result<Box<BarWidget>, Error> {
-        let devices = Path::new("/sys/class/backlight").read_dir()?;
-
-        let first_device = match devices.take(1).next() {
-            Some(v) => match v {
-                Ok(v) => v,
-                Err(_) => return Err(Error::new(ErrorKind::Other, "no backlight device")),
-            },
-            None => return Err(Error::new(ErrorKind::Other, "no backlight device")),
-        };
+    pub fn new(path: &str, font_size: f32, length: u32) -> Result<Box<BarWidget>, Error> {
         let mut dev = Backlight {
-            device_path: first_device.path(),
+            device_path: Path::new("/sys/class/backlight").to_path_buf().join(path),
             cur_brightness: 0,
             max_brightness: 0,
         };