触摸类型对比
| 对比项 | USB 触摸屏 | I2C 触摸屏 |
|---|---|---|
| 通信方式 | USB HID 协议（标准接口） | I2C 总线（私有协议） |
| 数据传输方式 | 通过 HID 事件发送触摸数据 | 通过 I2C 读取寄存器数据 |
| 驱动层 | 标准 HID 触摸驱动（hid-multitouch.c），由 Android InputReader 处理 | 定制 I2C 触摸驱动，厂商自定义协议 |
| 事件处理 | 通过 /dev/input/eventX 直接传输 |
需要从 I2C 设备读取数据 |
| 旋转支持 | 系统层面支持（可通过 idc 或 InputReader 旋转） |
驱动层需要额外适配 |
| 旋转方式 | 通过 idc 配置 swapXY、invertX、invertY |
需要修改驱动代码手动调整坐标 |
| 框架支持 | Android 自带 HID 触摸屏支持，可以通过 InputReader.cpp 处理 |
不通用，不同 I2C 触摸芯片需要不同适配 |
| 是否需要修改驱动 | ❌ 通常不需要，可直接调整 .idc 文件 |
✅ 需要修改内核驱动代码 |
| 实现难度 | ⭐（简单，修改 .idc 即可） |
⭐⭐⭐（复杂，需要改驱动代码） |
汇顶I2C触摸旋转
ctp {
status = "okay";
compatible = "allwinner,goodix";
reg = <0x5d>;
device_type = "ctp";
ctp_name = "gt9xxnew_ts";
ctp_twi_id = <0x1>;
ctp_twi_addr = <0x5d>;
ctp_screen_max_x = <1024>;
ctp_screen_max_y = <600>;
ctp_revert_x_flag = <1>;
ctp_revert_y_flag = <1>;
ctp_exchange_x_y_flag = <0>;
ctp_int_port = <&pio PH 18 6 0xffffffff 0xffffffff 0>;
ctp_wakeup = <&pio PH 19 1 0xffffffff 0xffffffff 1>;
ctp-supply = <®_ldoio0>;
ctp_power_ldo_vol = <3300>;
};
| 旋转角度 | ctp_revert_x_flag | ctp_revert_y_flag | ctp_exchange_x_y_flag |
|---|---|---|---|
| 0° (默认) | 0 | 0 | 0 |
| 90° | 0 | 1 | 1 |
| 180° | 1 | 1 | 0 |
| 270° | 1 | 0 | 1 |
A133 显示方向旋转
首先确定0度显示方向, 然后增加可以修改的显示方向属性
PRODUCT_PROPERTY_OVERRIDES += ro.surface_flinger.primary_display_orientation=ORIENTATION_0
PRODUCT_PROPERTY_OVERRIDES += persist.sys.primary_display_orientation=0
修改framework支持动态旋转
android/frameworks/native/services/surfaceflinger/SurfaceFlinger.cpp
SurfaceFlinger::SurfaceFlinger(Factory& factory) : SurfaceFlinger(factory, SkipInitialization) {
ALOGI("SurfaceFlinger is starting");
auto tmpPrimaryDisplayOrientation = primary_display_orientation(
SurfaceFlingerProperties::primary_display_orientation_values::ORIENTATION_0);
switch (tmpPrimaryDisplayOrientation) {
case SurfaceFlingerProperties::primary_display_orientation_values::ORIENTATION_90:
SurfaceFlinger::primaryDisplayOrientation = DisplayState::eOrientation90;
break;
case SurfaceFlingerProperties::primary_display_orientation_values::ORIENTATION_180:
SurfaceFlinger::primaryDisplayOrientation = DisplayState::eOrientation180;
break;
case SurfaceFlingerProperties::primary_display_orientation_values::ORIENTATION_270:
SurfaceFlinger::primaryDisplayOrientation = DisplayState::eOrientation270;
break;
default:
SurfaceFlinger::primaryDisplayOrientation = DisplayState::eOrientationDefault;
break;
}
// lixiaogang add start
int32_t user_rotation = property_get_int32("persist.sys.primary_display_orientation", int32_t(0));
switch (user_rotation) {
case 90:
SurfaceFlinger::primaryDisplayOrientation = DisplayState::eOrientation90;
break;
case 180:
SurfaceFlinger::primaryDisplayOrientation = DisplayState::eOrientation180;
break;
case 270:
SurfaceFlinger::primaryDisplayOrientation = DisplayState::eOrientation270;
break;
default:
break;
}
// lixiaogang add end
}
触摸随屏幕旋转
framework/native/services/inputflinger/InputReader.cpp
void TouchInputMapper::configureParameters() {
// Initial downs on external touch devices should wake the device.
// Normally we don't do this for internal touch screens to prevent them from waking
// up in your pocket but you can enable it using the input device configuration.
mParameters.wake = getDevice()->isExternal();
getDevice()->getConfiguration().tryGetProperty(String8("touch.wake"),
mParameters.wake);
// modify by lixiaogang
// modify ro.input_flinger.primary_touch.rotation to persist.sys.primary_display_orientation
int rotation = 0;
if (!(!mParameters.associatedDisplayIsExternal &&
(rotation = (int)property_get_int32("persist.sys.primary_display_orientation", -1)) != -1)) {
if (!getDevice()->getConfiguration().tryGetProperty(String8("touch.rotation"), rotation)) {
rotation = 0;
}
}
switch (rotation) {
case 90:
mParameters.rotation = Parameters::ROTATION_90;
break;
case 180:
mParameters.rotation = Parameters::ROTATION_180;
break;
case 270:
mParameters.rotation = Parameters::ROTATION_270;
break;
default:
mParameters.rotation = Parameters::ROTATION_0;
break;
}
}
