Refactor vga driver (#688)

* Add blank command

* Move vga driver to module

* Remove vga command

* Split vga module

* Rename vga device type

* Add /dev/vga/mode device file

* Restore font after mode change

* Remove cvs support for palette

* Refactor api::vga::color

* Move api::vga::color to sys::vga::color

* Move api::vga::palette to sys::vga::palette

* Use 256 colors palette

* Refactor Color

* Rename Color#to_vga_reg to Color#register

* Add Palette#set

* Add write-only /dev/vga/palette

* Remove unused set_palette

* Add read operation to /dev/vga/palette

* Add palette backup and restore

* Check for device presence

* Backup palette only in 80x25 mode

* Clear screen on mode change

* Make /dev/vga/mode readable

* Fix double buffer allocation

* Add framebuffer:addr()

* Add /dev/vga/buffer device

* Reorder device files

* Rename some functions

* Move test

* Run clippy

* Add color test

* Refactor code

* Move blank to userspace

Makefile

@@ -49,6 +49,7 @@ user-rust:
 	basename -s .rs src/bin/*.rs | xargs -I {} \
 		cargo rustc $(user-cargo-opts) --bin {}
 	cargo rustc $(user-cargo-opts) --bin exec -- $(linker-opts)
+	cargo rustc $(user-cargo-opts) --bin blank -- $(linker-opts)
 	cargo rustc $(user-cargo-opts) --bin hello -- $(linker-opts)
 	cargo rustc $(user-cargo-opts) --bin geocal -- $(linker-opts)
 	cargo rustc $(user-cargo-opts) --bin geodate -- $(linker-opts)

dsk/var/pkg/blank

@@ -0,0 +1 @@
+/bin/blank

dsk/var/pkg/index.html

@@ -1,4 +1,5 @@
 beep
+blank
 chess
 exec
 fonts

src/api/fs.rs

@@ -154,20 +154,24 @@ fn device_buffer(name: &str) -> Result<Vec<u8>, ()> {
     Ok(buf)
 }
 
+// TODO: Move this to sys::fs::device
 fn device_type(name: &str) -> Result<DeviceType, ()> {
     match name {
-        "null"     => Ok(DeviceType::Null),
-        "file"     => Ok(DeviceType::File),
-        "console"  => Ok(DeviceType::Console),
-        "random"   => Ok(DeviceType::Random),
-        "uptime"   => Ok(DeviceType::Uptime),
-        "realtime" => Ok(DeviceType::Realtime),
-        "rtc"      => Ok(DeviceType::RTC),
-        "tcp"      => Ok(DeviceType::TcpSocket),
-        "udp"      => Ok(DeviceType::UdpSocket),
-        "font"     => Ok(DeviceType::VgaFont),
-        "ata"      => Ok(DeviceType::Drive),
-        _          => Err(()),
+        "null"        => Ok(DeviceType::Null),
+        "file"        => Ok(DeviceType::File),
+        "console"     => Ok(DeviceType::Console),
+        "random"      => Ok(DeviceType::Random),
+        "uptime"      => Ok(DeviceType::Uptime),
+        "realtime"    => Ok(DeviceType::Realtime),
+        "rtc"         => Ok(DeviceType::RTC),
+        "tcp"         => Ok(DeviceType::TcpSocket),
+        "udp"         => Ok(DeviceType::UdpSocket),
+        "vga-buffer"  => Ok(DeviceType::VgaBuffer),
+        "vga-font"    => Ok(DeviceType::VgaFont),
+        "vga-mode"    => Ok(DeviceType::VgaMode),
+        "vga-palette" => Ok(DeviceType::VgaPalette),
+        "ata"         => Ok(DeviceType::Drive),
+        _             => Err(()),
     }
 }
 

src/api/vga/mod.rs

@@ -1,5 +1,16 @@
-pub mod color;
-pub mod palette;
+use crate::api::fs;
 
-pub use color::Color;
-pub use palette::Palette;
+pub fn graphic_mode() {
+    let dev = "/dev/vga/mode";
+    if fs::is_device(dev) {
+        fs::write(dev, b"320x200").ok();
+    }
+}
+
+pub fn text_mode() {
+    let dev = "/dev/vga/mode";
+    if fs::is_device(dev) {
+        fs::write(dev, b"80x25").ok();
+        print!("\x1b[2J\x1b[1;1H"); // Clear screen and move to top
+    }
+}

src/bin/blank.rs

@@ -0,0 +1,20 @@
+#![no_std]
+#![no_main]
+
+extern crate alloc;
+
+use moros::print;
+use moros::api::io;
+use moros::api::vga;
+use moros::entry_point;
+
+entry_point!(main);
+
+fn main(_args: &[&str]) {
+    vga::graphic_mode();
+    print!("\x1b]R\x1b[1A"); // Reset palette
+    while io::stdin().read_char().is_none() {
+        x86_64::instructions::hlt();
+    }
+    vga::text_mode();
+}