platform_hardware_interfaces/automotive/evs/1.0/IEvsDisplay.hal
Changyeon Jo 1d0f024bd7 Update comments on EVS 1.0 interfaces
This change fixes hidl-lint errors and warnings in EVS 1.0 interface
definitions.

Bug: 135472573
Change-Id: I4b6b5df792875a8dde2ee146f88fb401a4d5e860
Signed-off-by: Changyeon Jo <changyeon@google.com>
2019-07-31 07:54:25 -07:00

91 lines
3.7 KiB
Text

/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.hardware.automotive.evs@1.0;
/**
* Represents a single camera and is the primary interface for capturing images.
*/
interface IEvsDisplay {
/**
* Returns basic information about the EVS display provided by the system.
*
* See the description of the DisplayDesc structure for details.
*
* @return info The description of this display. Please see the description
* of the DisplayDesc structure for details.
*/
getDisplayInfo() generates (DisplayDesc info);
/**
* Clients may set the display state to express their desired state.
*
* The HAL implementation must gracefully accept a request for any state while in
* any other state, although the response may be to defer or ignore the request. The display
* is defined to start in the NOT_VISIBLE state upon initialization. The client is
* then expected to request the VISIBLE_ON_NEXT_FRAME state, and then begin providing
* video. When the display is no longer required, the client is expected to request
* the NOT_VISIBLE state after passing the last video frame.
* Returns INVALID_ARG if the requested state is not a recognized value.
*
* @param state Desired new DisplayState.
* @return result EvsResult::OK is returned if this call is successful.
*/
setDisplayState(DisplayState state) generates (EvsResult result);
/**
* This call requests the current state of the display
*
* The HAL implementation should report the actual current state, which might
* transiently differ from the most recently requested state. Note, however, that
* the logic responsible for changing display states should generally live above
* the device layer, making it undesirable for the HAL implementation to spontaneously
* change display states.
*
* @return state Current DisplayState of this Display.
*/
getDisplayState() generates (DisplayState state);
/**
* This call returns a handle to a frame buffer associated with the display.
*
* @return buffer A handle to a frame buffer. The returned buffer may be
* locked and written to by software and/or GL. This buffer
* must be returned via a call to
* returnTargetBufferForDisplay() even if the display is no
* longer visible.
*/
getTargetBuffer() generates (BufferDesc buffer);
/**
* This call tells the display that the buffer is ready for display.
*
* The buffer is no longer valid for use by the client after this call.
* There is no maximum time the caller may hold onto the buffer before making this
* call. The buffer may be returned at any time and in any DisplayState, but all
* buffers are expected to be returned before the IEvsDisplay interface is destroyed.
*
* @param buffer A buffer handle to the frame that is ready for display.
* @return result EvsResult::OK is returned if this call is successful.
*/
returnTargetBufferForDisplay(BufferDesc buffer) generates (EvsResult result);
};