Merge usb-mass-storage branch

kernel/src/storage.rs

@@ -0,0 +1,100 @@
+use embassy_rp::gpio::{Input, Output};
+use embassy_rp::peripherals::SPI0;
+use embassy_rp::spi::{Blocking, Spi};
+use embassy_time::Delay;
+use embedded_hal_bus::spi::ExclusiveDevice;
+use embedded_sdmmc::{
+    Block, BlockCount, BlockDevice, BlockIdx, Directory, SdCard as SdmmcSdCard, TimeSource,
+    Timestamp, Volume, VolumeIdx, VolumeManager, sdcard::Error,
+};
+
+pub const MAX_DIRS: usize = 4;
+pub const MAX_FILES: usize = 5;
+pub const MAX_VOLUMES: usize = 1;
+
+type Device = ExclusiveDevice<Spi<'static, SPI0, Blocking>, Output<'static>, embassy_time::Delay>;
+type SD = SdmmcSdCard<Device, Delay>;
+type VolMgr = VolumeManager<SD, DummyTimeSource, MAX_DIRS, MAX_FILES, MAX_VOLUMES>;
+type Vol<'a> = Volume<'a, SD, DummyTimeSource, MAX_DIRS, MAX_FILES, MAX_VOLUMES>;
+type Dir<'a> = Directory<'a, SD, DummyTimeSource, MAX_DIRS, MAX_FILES, MAX_VOLUMES>;
+
+pub struct DummyTimeSource {}
+impl TimeSource for DummyTimeSource {
+    fn get_timestamp(&self) -> Timestamp {
+        Timestamp::from_calendar(2022, 1, 1, 0, 0, 0).unwrap()
+    }
+}
+
+pub struct SdCard {
+    det: Input<'static>,
+    volume_mgr: VolMgr,
+}
+
+impl SdCard {
+    pub const BLOCK_SIZE: u16 = 512;
+
+    pub fn new(sdcard: SD, det: Input<'static>) -> Self {
+        let volume_mgr = VolumeManager::<_, _, MAX_DIRS, MAX_FILES, MAX_VOLUMES>::new_with_limits(
+            sdcard,
+            DummyTimeSource {},
+            5000,
+        );
+        Self {
+            det: det,
+            volume_mgr,
+        }
+    }
+
+    /// Returns true if an SD card is inserted.
+    /// The DET pin is active-low via mechanical switch in the socket.
+    pub fn is_attached(&self) -> bool {
+        self.det.is_low()
+    }
+
+    pub fn open_volume(&mut self) -> Result<Vol<'_>, ()> {
+        if self.is_attached() {
+            return Ok(self.volume_mgr.open_volume(VolumeIdx(0)).map_err(|_| ())?);
+        }
+        Err(())
+    }
+
+    pub fn size(&self) -> u64 {
+        let mut result = 0;
+
+        self.volume_mgr.device(|sd| {
+            result = sd.num_bytes().unwrap_or(0);
+            DummyTimeSource {}
+        });
+
+        result
+    }
+
+    pub fn num_blocks(&self) -> u32 {
+        let mut result = 0;
+
+        self.volume_mgr.device(|sd| {
+            result = sd.num_blocks().unwrap_or(BlockCount(0)).0;
+            DummyTimeSource {}
+        });
+
+        result
+    }
+
+    pub fn read_blocks(&self, blocks: &mut [Block], start_block_idx: BlockIdx) -> Result<(), ()> {
+        let mut res: Result<(), Error> = Ok(());
+        self.volume_mgr.device(|sd| {
+            res = sd.read(blocks, start_block_idx);
+            DummyTimeSource {}
+        });
+        res.map_err(|_| ())
+    }
+
+    pub fn write_blocks(&self, blocks: &mut [Block], start_block_idx: BlockIdx) -> Result<(), ()> {
+        let mut res: Result<(), Error> = Ok(());
+        self.volume_mgr.device(|sd| {
+            let res = sd.write(blocks, start_block_idx);
+            DummyTimeSource {}
+        });
+        res.map_err(|_| ())
+    }
+}