Screen API implementation

Cargo.toml

@@ -41,6 +41,7 @@ libtock_low_level_debug = { path = "apis/kernel/low_level_debug" }
 libtock_ninedof = { path = "apis/sensors/ninedof" }
 libtock_platform = { path = "platform" }
 libtock_proximity = { path = "apis/sensors/proximity" }
+libtock_screen = { path = "apis/display/screen" }
 libtock_rng = { path = "apis/peripherals/rng" }
 libtock_runtime = { path = "runtime" }
 libtock_small_panic = { path = "panic_handlers/small_panic" }
@@ -82,6 +83,7 @@ members = [
     "apis/sensors/air_quality",
     "apis/sensors/ambient_light",
     "apis/sensors/ninedof",
+    "apis/display/screen",
     "apis/sensors/proximity",
     "apis/sensors/temperature",
     "apis/storage/key_value",

apis/display/screen/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "libtock_screen"
+version = "0.1.0"
+authors = ["Tock Project Developers <[email protected]>"]
+license = "Apache-2.0 OR MIT"
+edition = "2021"
+repository = "https://www.github.com/tock/libtock-rs"
+rust-version.workspace = true
+description = "libtock display driver"
+
+[dependencies]
+libtock_platform = { path = "../../../platform" }
+
+[dev-dependencies]
+libtock_unittest = { path = "../../../unittest" }

apis/display/screen/src/lib.rs

@@ -0,0 +1,318 @@
+#![no_std]
+use core::cell::Cell;
+use libtock_platform::allow_ro::AllowRo;
+use libtock_platform::share;
+use libtock_platform::subscribe::Subscribe;
+use libtock_platform::{self as platform, DefaultConfig};
+use libtock_platform::{ErrorCode, Syscalls};
+
+pub struct Screen<S: Syscalls, C: Config = DefaultConfig>(S, C);
+
+impl<S: Syscalls, C: Config> Screen<S, C> {
+    /// Check if the Screen driver exists
+    pub fn exists() -> Result<(), ErrorCode> {
+        let val = S::command(DRIVER_NUM, command::EXISTS, 0, 0).is_success();
+        if val {
+            Ok(())
+        } else {
+            Err(ErrorCode::Fail)
+        }
+    }
+
+    /// Perform initial screen setup
+    pub fn screen_setup() -> Result<u32, ErrorCode> {
+        S::command(DRIVER_NUM, command::SCREEN_SETUP, 0, 0).to_result()
+    }
+
+    /// Turn on Screen power
+    pub fn set_power(value: usize) -> Result<(), ErrorCode> {
+        if value != 0 {
+            S::command(DRIVER_NUM, command::SET_POWER, value as u32, 0).to_result()
+        } else {
+            Err(ErrorCode::Invalid)
+        }
+    }
+
+    /// Set screen brightness, wait for completion via subscribe
+    pub fn set_brightness(value: usize) -> Result<(), ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(DRIVER_NUM, command::SET_BRIGHTNESS, value as u32, 0).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Turn on screen color inversion
+    pub fn set_invert_on() -> Result<(), ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(DRIVER_NUM, command::SET_INVERT_ON, 0, 0).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Turn off screen color inversion
+    pub fn set_invert_off() -> Result<(), ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(DRIVER_NUM, command::SET_INVERT_OFF, 0, 0).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Set inversion using a numeric value (non-zero = on)
+    pub fn set_invert(value: usize) -> Result<(), ErrorCode> {
+        if value != 0 {
+            S::command(DRIVER_NUM, command::SET_INVERT, value as u32, 0).to_result()
+        } else {
+            Err(ErrorCode::Invalid)
+        }
+    }
+
+    /// Get the number of supported resolution modes
+    pub fn get_resolution_modes_count() -> Result<u32, ErrorCode> {
+        S::command(DRIVER_NUM, command::GET_RESOLUTION_MODES_COUNT, 0, 0).to_result()
+    }
+
+    /// Get width and height for a given resolution index
+    pub fn get_resolution_width_height(index: usize) -> Result<(u32, u32), ErrorCode> {
+        S::command(
+            DRIVER_NUM,
+            command::GET_RESOLUTION_WIDTH_HEIGHT,
+            index as u32,
+            0,
+        )
+        .to_result()
+    }
+
+    /// Get the number of supported pixel modes
+    pub fn pixel_modes_count() -> Result<u32, ErrorCode> {
+        S::command(DRIVER_NUM, command::PIXEL_MODES_COUNT, 0, 0).to_result()
+    }
+
+    /// Get the pixel format at a specific index
+    pub fn pixel_format(index: usize) -> Result<u32, ErrorCode> {
+        S::command(DRIVER_NUM, command::PIXEL_FORMAT, index as u32, 0).to_result()
+    }
+
+    /// Get the current rotation of the screen
+    pub fn get_rotation() -> Result<u32, ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(DRIVER_NUM, command::GET_ROTATION, 0, 0).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Set the screen rotation
+    pub fn set_rotation(rotation: usize) -> Result<(), ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(DRIVER_NUM, command::SET_ROTATION, rotation as u32, 0).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Get the currently set screen resolution
+    pub fn get_resolution() -> Result<(u32, u32), ErrorCode> {
+        S::command(DRIVER_NUM, command::GET_RESOLUTION, 0, 0).to_result()
+    }
+
+    /// Set the screen resolution
+    pub fn set_resolution(width: usize, height: usize) -> Result<(), ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(
+                DRIVER_NUM,
+                command::SET_RESOLUTION,
+                width as u32,
+                height as u32,
+            )
+            .to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Get the currently set pixel format
+    pub fn get_pixel_format() -> Result<u32, ErrorCode> {
+        S::command(DRIVER_NUM, command::GET_PIXEL_FORMAT, 0, 0).to_result()
+    }
+
+    /// Set the pixel format
+    pub fn set_pixel_format(format: usize) -> Result<(), ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val =
+                S::command(DRIVER_NUM, command::SET_PIXEL_FORMAT, format as u32, 0).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Define the region of the screen that will be written to
+    pub fn set_write_frame(x: u32, y: u32, width: u32, height: u32) -> Result<(), ErrorCode> {
+        let data1: u32 = ((x & 0xFFFF) << 16_u8) | (y & 0xFFFF);
+        let data2: u32 = ((width & 0xFFFF) << 16_u8) | (height & 0xFFFF);
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope(|subscribe| {
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(DRIVER_NUM, command::SET_WRITE_FRAME, data1, data2).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Write data to the screen using the given buffer
+    pub fn write(s: &[u8]) -> Result<(), ErrorCode> {
+        let called: Cell<Option<(u32,)>> = Cell::new(None);
+        share::scope::<
+            (
+                AllowRo<_, DRIVER_NUM, { allow_ro::WRITE_BUFFER_ID }>,
+                Subscribe<_, DRIVER_NUM, { subscribe::WRITE }>,
+            ),
+            _,
+            _,
+        >(|handle| {
+            let (allow_ro, subscribe) = handle.split();
+            S::allow_ro::<C, DRIVER_NUM, { allow_ro::WRITE_BUFFER_ID }>(allow_ro, s)?;
+            S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+            let val = S::command(DRIVER_NUM, command::WRITE, s.len() as u32, 0).to_result();
+            loop {
+                S::yield_wait();
+                if let Some((_,)) = called.get() {
+                    return val;
+                }
+            }
+        })
+    }
+
+    /// Fill the screen
+    pub fn fill(s: &mut [u8], color: u16) -> Result<(), ErrorCode> {
+        if s.len() >= 2 {
+            s[0] = ((color >> 8) & 0xFF) as u8;
+            s[1] = (color & 0xFF) as u8;
+
+            let called: Cell<Option<(u32,)>> = Cell::new(None);
+            share::scope::<
+                (
+                    AllowRo<_, DRIVER_NUM, { allow_ro::WRITE_BUFFER_ID }>,
+                    Subscribe<_, DRIVER_NUM, { subscribe::WRITE }>,
+                ),
+                _,
+                _,
+            >(|handle| {
+                let (allow_ro, subscribe) = handle.split();
+                S::allow_ro::<C, DRIVER_NUM, { allow_ro::WRITE_BUFFER_ID }>(allow_ro, s)?;
+                S::subscribe::<_, _, C, DRIVER_NUM, { subscribe::WRITE }>(subscribe, &called)?;
+                let val = S::command(DRIVER_NUM, command::FILL, 0, 0).to_result();
+                loop {
+                    S::yield_wait();
+                    if let Some((_,)) = called.get() {
+                        return val;
+                    }
+                }
+            })
+        } else {
+            Err(ErrorCode::Fail)
+        }
+    }
+}
+
+pub trait Config:
+    platform::allow_ro::Config + platform::allow_rw::Config + platform::subscribe::Config
+{
+}
+
+impl<T: platform::allow_ro::Config + platform::allow_rw::Config + platform::subscribe::Config>
+    Config for T
+{
+}
+
+#[cfg(test)]
+mod tests;
+
+// -----------------------------------------------------------------------------
+// Driver number and command IDs
+// -----------------------------------------------------------------------------
+
+const DRIVER_NUM: u32 = 0x90001;
+
+// Command IDs
+#[allow(unused)]
+mod command {
+    pub const EXISTS: u32 = 0;
+    pub const SCREEN_SETUP: u32 = 1;
+    pub const SET_POWER: u32 = 2;
+    pub const SET_BRIGHTNESS: u32 = 3;
+    pub const SET_INVERT_ON: u32 = 4;
+    pub const SET_INVERT_OFF: u32 = 5;
+    pub const SET_INVERT: u32 = 6;
+    pub const GET_RESOLUTION_MODES_COUNT: u32 = 11;
+    pub const GET_RESOLUTION_WIDTH_HEIGHT: u32 = 12;
+    pub const PIXEL_MODES_COUNT: u32 = 13;
+    pub const PIXEL_FORMAT: u32 = 14;
+    pub const GET_ROTATION: u32 = 21;
+    pub const SET_ROTATION: u32 = 22;
+    pub const GET_RESOLUTION: u32 = 23;
+    pub const SET_RESOLUTION: u32 = 24;
+    pub const GET_PIXEL_FORMAT: u32 = 25;
+    pub const SET_PIXEL_FORMAT: u32 = 26;
+    pub const SET_WRITE_FRAME: u32 = 100;
+    pub const WRITE: u32 = 200;
+    pub const FILL: u32 = 300;
+}
+
+// Subscribe ID used for callbacks
+mod subscribe {
+    pub const WRITE: u32 = 0;
+}
+
+// Allow-readonly buffer ID
+mod allow_ro {
+    pub const WRITE_BUFFER_ID: u32 = 0;
+}