Add planes example

This shows information about DRM planes, under the CRTC and connector
they are associated with. I've found this useful for trying to
understand what's going on with planes vs trying to read `drm_info`
output, so it may as well be added here.

Author: ids1024

examples/planes.rs

@@ -0,0 +1,156 @@
+use drm::control::property::Value;
+use std::{collections::HashMap, fs, io};
+
+pub mod utils;
+use crate::utils::*;
+
+fn convert_value((type_, value): &(drm::control::property::ValueType, u64)) -> Value<'_> {
+    type_.convert_value(*value)
+}
+
+// 16.16 fixed point
+fn convert_value_fixed((type_, value): &(drm::control::property::ValueType, u64)) -> Option<f64> {
+    let val = type_.convert_value(*value).as_unsigned_range()? as u32;
+    Some(val as f64 / 0xffff as f64)
+}
+
+fn display_plane(
+    card: &Card,
+    plane_handle: drm::control::plane::Handle,
+    plane: drm::control::plane::Info,
+) -> io::Result<()> {
+    let props = card.get_properties(plane_handle)?;
+    let mut prop_map = HashMap::new();
+    for (handle, value) in &props {
+        let info = card.get_property(*handle)?;
+        let name = info.name().to_str().unwrap().to_owned();
+        prop_map.insert(name, (info.value_type(), *value));
+    }
+    let Value::Enum(Some(type_)) = convert_value(&prop_map["type"]) else {
+        panic!("failed to convert plane type enum");
+    };
+    println!("        Type: {}", type_.name().to_str().unwrap());
+    println!(
+        "        CRTC_XYWH: ({}, {}) {}x{}",
+        convert_value(&prop_map["CRTC_X"])
+            .as_signed_range()
+            .unwrap(),
+        convert_value(&prop_map["CRTC_Y"])
+            .as_signed_range()
+            .unwrap(),
+        convert_value(&prop_map["CRTC_W"])
+            .as_unsigned_range()
+            .unwrap(),
+        convert_value(&prop_map["CRTC_H"])
+            .as_unsigned_range()
+            .unwrap()
+    );
+    println!(
+        "        SRC_XYWH: ({:.1}, {:.1}) {:.1}x{:.1}",
+        convert_value_fixed(&prop_map["SRC_X"]).unwrap(),
+        convert_value_fixed(&prop_map["SRC_Y"]).unwrap(),
+        convert_value_fixed(&prop_map["SRC_W"]).unwrap(),
+        convert_value_fixed(&prop_map["SRC_H"]).unwrap()
+    );
+    if let Some(framebuffer_handle) = plane.framebuffer() {
+        println!("        {:?}", framebuffer_handle);
+        let framebuffer = card.get_planar_framebuffer(framebuffer_handle).unwrap();
+        println!("          Format: {:?}", framebuffer.pixel_format());
+        if let Some(modifier) = framebuffer.modifier() {
+            println!("          Modifier: {:?}", modifier);
+        }
+        println!(
+            "          Size: {}x{}",
+            framebuffer.size().0,
+            framebuffer.size().1
+        );
+
+        println!("          Planes");
+        for i in 0..4 {
+            println!(
+                "            Plane {} (offset: {}, pitch: {})",
+                i,
+                framebuffer.offsets()[i],
+                framebuffer.pitches()[i]
+            );
+        }
+    }
+    Ok(())
+}
+
+fn display_card(card: &Card) -> io::Result<()> {
+    for &cap in capabilities::CLIENT_CAP_ENUMS {
+        card.set_client_capability(cap, true)?;
+    }
+
+    let resources = card.resource_handles()?;
+
+    let mut planes = Vec::new();
+    for connector_handle in resources.connectors() {
+        let connector = card.get_connector(*connector_handle, false)?;
+        if connector.state() != drm::control::connector::State::Connected {
+            continue;
+        }
+
+        println!("  {:?}", connector_handle);
+        println!(
+            "    {:?}{}",
+            connector.interface(),
+            connector.interface_id()
+        );
+        if let Some(encoder_handle) = connector.current_encoder() {
+            let encoder = card.get_encoder(encoder_handle)?;
+            println!("    {:?}", encoder_handle);
+            println!("      Kind: {:?}", encoder.kind());
+            if let Some(crtc_handle) = encoder.crtc() {
+                println!("    {:?}", crtc_handle);
+                let crtc = card.get_crtc(crtc_handle)?;
+                if let Some(mode) = crtc.mode() {
+                    println!("      {:?}", mode);
+                }
+                for plane_handle in card.plane_handles()? {
+                    let plane = card.get_plane(plane_handle)?;
+                    if plane.crtc() != Some(crtc_handle) {
+                        continue;
+                    }
+                    planes.push(plane_handle);
+                    println!("      {:?}", plane_handle);
+                    display_plane(card, plane_handle, plane)?;
+                }
+            }
+        }
+    }
+
+    println!("Planes not associated with connector");
+    for plane_handle in card.plane_handles()? {
+        if !planes.contains(&plane_handle) {
+            let plane = card.get_plane(plane_handle)?;
+            println!("      {:?}", plane_handle);
+            display_plane(card, plane_handle, plane)?;
+        }
+    }
+
+    Ok(())
+}
+
+fn main() -> io::Result<()> {
+    for i in fs::read_dir("/dev/dri")? {
+        let i = i?;
+        if i.file_name().to_str().unwrap().starts_with("card") {
+            if let Ok(card) = Card::open(i.path().to_str().unwrap()) {
+                let driver = card.get_driver()?;
+                println!(
+                    "{} ({}, {}, version {}.{}.{})",
+                    i.path().display(),
+                    driver.name.to_str().unwrap(),
+                    driver.desc.to_str().unwrap(),
+                    driver.version.0,
+                    driver.version.1,
+                    driver.version.2
+                );
+                display_card(&card)?;
+            }
+        }
+    }
+    Ok(())
+}

examples/utils/mod.rs

@@ -2,6 +2,7 @@
 
 pub use drm::control::Device as ControlDevice;
 pub use drm::Device;
+use std::io;
 
 #[derive(Debug)]
 /// A simple wrapper for a device node.
@@ -21,15 +22,15 @@ impl ControlDevice for Card {}
 
 /// Simple helper methods for opening a `Card`.
 impl Card {
-    pub fn open(path: &str) -> Self {
+    pub fn open(path: &str) -> io::Result<Self> {
         let mut options = std::fs::OpenOptions::new();
         options.read(true);
         options.write(true);
-        Card(options.open(path).unwrap())
+        Ok(Card(options.open(path)?))
     }
 
     pub fn open_global() -> Self {
-        Self::open("/dev/dri/card0")
+        Self::open("/dev/dri/card0").unwrap()
     }
 }