Add build features for multiple device types

The bin crate now has two features, one for each supported device.

* The IOCTL change from #142 is compiled in conditionally.
* Tp-link display is supported & tested for HW rev 3 and HW rev 5.

The release tarballs now contain two rayhunter-daemon binaries, for
orbic and tplink. An installer for tplink is not yet included.

Co-authored-by: m0veax <m0veax@chaospott.de>

bin/src/display/tplink_framebuffer.rs

@@ -0,0 +1,93 @@
+use std::fs::File;
+use std::io::Write;
+use std::os::fd::AsRawFd;
+
+use crate::config;
+use crate::display::DisplayState;
+use crate::display::generic_framebuffer::{self, GenericFramebuffer, Dimensions};
+
+use tokio::sync::oneshot;
+use tokio::sync::mpsc::Receiver;
+use tokio_util::task::TaskTracker;
+
+const FB_PATH: &str = "/dev/fb0";
+
+struct Framebuffer;
+
+#[repr(C)]
+struct fb_fillrect {
+    dx: u32,
+    dy: u32,
+    width: u32,
+    height: u32,
+    color: u32,
+    rop: u32,
+}
+
+impl GenericFramebuffer for Framebuffer {
+    fn dimensions(&self) -> Dimensions {
+        // TODO actually poll for this, maybe w/ fbset?
+        Dimensions {
+            height: 128,
+            width: 128,
+        }
+    }
+
+    fn write_buffer(
+        &mut self,
+        buffer: &[(u8, u8, u8)],
+    ) {
+        // for how to write to the buffer, consult M7350v5_en_gpl/bootable/recovery/recovery_color_oled.c
+        let dimensions = self.dimensions();
+        let width = dimensions.width;
+        let height = buffer.len() as u32 / width;
+        let mut f = File::options().write(true).open(FB_PATH).unwrap();
+        let mut arg = fb_fillrect {
+            dx: 0,
+            dy: 0,
+            width,
+            height,
+            color: 0xffff, // not sure what this is
+            rop: 0,
+        };
+
+        let mut raw_buffer = Vec::new();
+        for (r, g, b) in buffer {
+            let mut rgb565: u16 = (*r as u16 & 0b11111000) << 8;
+            rgb565 |= (*g as u16 & 0b11111100) << 3;
+            rgb565 |= (*b as u16) >> 3;
+            // note: big-endian!
+            raw_buffer.extend(rgb565.to_be_bytes());
+        }
+
+        f.write_all(&raw_buffer).unwrap();
+
+        unsafe {
+            let res = libc::ioctl(
+                f.as_raw_fd(),
+                0x4619,  // FBIORECT_DISPLAY
+                &mut arg as *mut _,
+                std::mem::size_of::<fb_fillrect>(),
+            );
+
+            if res < 0 {
+                panic!("failed to send FBIORECT_DISPLAY ioctl, {}", res);
+            }
+        }
+    }
+}
+
+pub fn update_ui(
+    task_tracker: &TaskTracker,
+    config: &config::Config,
+    ui_shutdown_rx: oneshot::Receiver<()>,
+    ui_update_rx: Receiver<DisplayState>
+) {
+    generic_framebuffer::update_ui(
+        task_tracker,
+        config,
+        Framebuffer,
+        ui_shutdown_rx,
+        ui_update_rx,
+    )
+}