Struct ScreenShared

pub struct ScreenShared<'a, S: Screen<'a>> { /* private fields */ }

A userspace driver that allows multiple apps to use the same screen.

Each app is given a pre-set rectangular region of the screen to use.

Implementations

impl<'a, S: Screen<'a>> ScreenShared<'a, S>

pub fn new( screen: &'a S, grant: Grant<App, UpcallCount<1>, AllowRoCount<{ ro_allow::COUNT }>, AllowRwCount<0>>, buffer: &'static mut [u8], apps_regions: &'a [AppScreenRegion], ) -> ScreenShared<'a, S>

Trait Implementations

impl<'a, S: Screen<'a>> ScreenClient for ScreenShared<'a, S>

fn command_complete(&self, r: Result<(), ErrorCode>)

The screen will call this function to notify that a command (except write) has finished.

fn write_complete( &self, data: SubSliceMut<'static, u8>, r: Result<(), ErrorCode>, )

The screen will call this function to notify that the write command has finished. This is different from command_complete as it has to pass back the write buffer

fn screen_is_ready(&self)

Some screens need some time to start, this function is called when the screen is ready.

impl<'a, S: Screen<'a>> SyscallDriver for ScreenShared<'a, S>

fn command( &self, command_num: usize, data1: usize, data2: usize, process_id: ProcessId, ) -> CommandReturn

System call for a process to perform a short synchronous operation or start a long-running split-phase operation (whose completion is signaled with an upcall). Command 0 is a reserved command to detect if a peripheral system call driver is installed and must always return a CommandReturn::success.

fn allocate_grant(&self, processid: ProcessId) -> Result<(), Error>

Request to allocate a capsule’s grant for a specific process.

fn allow_userspace_readable( &self, app: ProcessId, which: usize, slice: ReadWriteProcessBuffer, ) -> Result<ReadWriteProcessBuffer, (ReadWriteProcessBuffer, ErrorCode)>

System call for a process to pass a buffer (a UserspaceReadableProcessBuffer) to the kernel that the kernel can either read or write. The kernel calls this method only after it checks that the entire buffer is within memory the process can both read and write.