| /* |
| * Copyright (C) 2018 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.hdmi; |
| |
| import android.annotation.IntDef; |
| |
| import java.lang.annotation.Retention; |
| import java.lang.annotation.RetentionPolicy; |
| |
| /** |
| * Various utilities related to HDMI CEC. |
| * |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public final class HdmiUtils { |
| /** |
| * Return value of {@link #getLocalPortFromPhysicalAddress(int, int)} |
| */ |
| static final int TARGET_NOT_UNDER_LOCAL_DEVICE = -1; |
| static final int TARGET_SAME_PHYSICAL_ADDRESS = 0; |
| |
| private HdmiUtils() { /* cannot be instantiated */ } |
| |
| /** |
| * Method to parse target physical address to the port number on the current device. |
| * |
| * <p>This check assumes target address is valid. |
| * |
| * @param targetPhysicalAddress is the physical address of the target device |
| * @param myPhysicalAddress is the physical address of the current device |
| * @return |
| * If the target device is under the current device, return the port number of current device |
| * that the target device is connected to. This also applies to the devices that are indirectly |
| * connected to the current device. |
| * |
| * <p>If the target device has the same physical address as the current device, return |
| * {@link #TARGET_SAME_PHYSICAL_ADDRESS}. |
| * |
| * <p>If the target device is not under the current device, return |
| * {@link #TARGET_NOT_UNDER_LOCAL_DEVICE}. |
| */ |
| public static int getLocalPortFromPhysicalAddress( |
| int targetPhysicalAddress, int myPhysicalAddress) { |
| if (myPhysicalAddress == targetPhysicalAddress) { |
| return TARGET_SAME_PHYSICAL_ADDRESS; |
| } |
| |
| int mask = 0xF000; |
| int finalMask = 0xF000; |
| int maskedAddress = myPhysicalAddress; |
| |
| while (maskedAddress != 0) { |
| maskedAddress = myPhysicalAddress & mask; |
| finalMask |= mask; |
| mask >>= 4; |
| } |
| |
| int portAddress = targetPhysicalAddress & finalMask; |
| if ((portAddress & (finalMask << 4)) != myPhysicalAddress) { |
| return TARGET_NOT_UNDER_LOCAL_DEVICE; |
| } |
| |
| mask <<= 4; |
| int port = portAddress & mask; |
| while ((port >> 4) != 0) { |
| port >>= 4; |
| } |
| return port; |
| } |
| |
| /** |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| @Retention(RetentionPolicy.SOURCE) |
| @IntDef({HDMI_RELATIVE_POSITION_UNKNOWN, HDMI_RELATIVE_POSITION_DIRECTLY_BELOW, |
| HDMI_RELATIVE_POSITION_BELOW, HDMI_RELATIVE_POSITION_SAME, |
| HDMI_RELATIVE_POSITION_DIRECTLY_ABOVE, HDMI_RELATIVE_POSITION_ABOVE, |
| HDMI_RELATIVE_POSITION_SIBLING, HDMI_RELATIVE_POSITION_DIFFERENT_BRANCH}) |
| public @interface HdmiAddressRelativePosition {} |
| /** |
| * HDMI relative position is not determined. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_UNKNOWN = 0; |
| /** |
| * HDMI relative position: directly blow the device. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_DIRECTLY_BELOW = 1; |
| /** |
| * HDMI relative position: indirectly below the device. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_BELOW = 2; |
| /** |
| * HDMI relative position: the same device. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_SAME = 3; |
| /** |
| * HDMI relative position: directly above the device. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_DIRECTLY_ABOVE = 4; |
| /** |
| * HDMI relative position: indirectly above the device. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_ABOVE = 5; |
| /** |
| * HDMI relative position: directly below a same device. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_SIBLING = 6; |
| /** |
| * HDMI relative position: different branch. |
| * TODO(b/110094868): unhide for Q |
| * @hide |
| */ |
| public static final int HDMI_RELATIVE_POSITION_DIFFERENT_BRANCH = 7; |
| |
| private static final int NPOS = -1; |
| |
| /** |
| * Check if the given physical address is valid. |
| * |
| * @param address physical address |
| * @return {@code true} if the given address is valid |
| */ |
| public static boolean isValidPhysicalAddress(int address) { |
| if (address < 0 || address >= 0xFFFF) { |
| return false; |
| } |
| int mask = 0xF000; |
| boolean hasZero = false; |
| for (int i = 0; i < 4; i++) { |
| if ((address & mask) == 0) { |
| hasZero = true; |
| } else if (hasZero) { |
| // only 0s are valid after a 0. |
| // e.g. 0x1012 is not valid. |
| return false; |
| } |
| mask >>= 4; |
| } |
| return true; |
| } |
| |
| |
| /** |
| * Returns the relative position of two physical addresses. |
| */ |
| @HdmiAddressRelativePosition |
| public static int getHdmiAddressRelativePosition(int src, int dest) { |
| if (src == 0xFFFF || dest == 0xFFFF) { |
| // address not assigned |
| return HDMI_RELATIVE_POSITION_UNKNOWN; |
| } |
| try { |
| int firstDiffPos = physicalAddressFirstDifferentDigitPos(src, dest); |
| if (firstDiffPos == NPOS) { |
| return HDMI_RELATIVE_POSITION_SAME; |
| } |
| int mask = (0xF000 >> (firstDiffPos * 4)); |
| int nextPos = firstDiffPos + 1; |
| if ((src & mask) == 0) { |
| // src is above dest |
| if (nextPos == 4) { |
| // last digits are different |
| return HDMI_RELATIVE_POSITION_DIRECTLY_ABOVE; |
| } |
| if (((0xF000 >> (nextPos * 4)) & dest) == 0) { |
| // next digit is 0 |
| return HDMI_RELATIVE_POSITION_DIRECTLY_ABOVE; |
| } |
| return HDMI_RELATIVE_POSITION_ABOVE; |
| } |
| |
| if ((dest & mask) == 0) { |
| // src is below dest |
| if (nextPos == 4) { |
| // last digits are different |
| return HDMI_RELATIVE_POSITION_DIRECTLY_BELOW; |
| } |
| if (((0xF000 >> (nextPos * 4)) & src) == 0) { |
| // next digit is 0 |
| return HDMI_RELATIVE_POSITION_DIRECTLY_BELOW; |
| } |
| return HDMI_RELATIVE_POSITION_BELOW; |
| } |
| if (nextPos == 4) { |
| // last digits are different |
| return HDMI_RELATIVE_POSITION_SIBLING; |
| } |
| if (((0xF000 >> (nextPos * 4)) & src) == 0 && ((0xF000 >> (nextPos * 4)) & dest) == 0) { |
| return HDMI_RELATIVE_POSITION_SIBLING; |
| } |
| return HDMI_RELATIVE_POSITION_DIFFERENT_BRANCH; |
| } catch (IllegalArgumentException e) { |
| // invalid address |
| return HDMI_RELATIVE_POSITION_UNKNOWN; |
| } |
| } |
| |
| private static int physicalAddressFirstDifferentDigitPos(int address1, int address2) |
| throws IllegalArgumentException { |
| if (!isValidPhysicalAddress(address1)) { |
| throw new IllegalArgumentException(address1 + " is not a valid address."); |
| } |
| if (!isValidPhysicalAddress(address2)) { |
| throw new IllegalArgumentException(address2 + " is not a valid address."); |
| } |
| int mask = 0xF000; |
| for (int i = 0; i < 4; i++) { |
| if ((address1 & mask) != (address2 & mask)) { |
| return i; |
| } |
| mask = mask >> 4; |
| } |
| return NPOS; |
| } |
| } |