14. As of Android Ice Cream Sandwich 4.0, touch screen drivers may need to be changed to comply with the Linux input protocol specification.
The following changes may be required:
When a tool becomes inactive (finger goes "up"), it should stop appearing in subsequent multi-touch sync reports. When all tools become inactive (all fingers go "up"), the driver should send an empty sync report packet, such as SYN_MT_REPORT followed by SYN_REPORT.
Previous versions of Android expected "up" events to be reported by sending a pressure value of 0. The old behavior was incompatible with the Linux input protocol specification and is no longer supported.
Physical pressure or signal strength information should be reported using ABS_MT_PRESSURE.
Previous versions of Android retrieved pressure information from ABS_MT_TOUCH_MAJOR. The old behavior was incompatible with the Linux input protocol specification and is no longer supported.
Touch size information should be reported using ABS_MT_TOUCH_MAJOR.
Previous versions of Android retrieved size information from ABS_MT_TOOL_MAJOR. The old behavior was incompatible with the Linux input protocol specification and is no longer supported.
Touch device drivers no longer need Android-specific customizations. By relying on the standard Linux input protocol, Android can support a wider variety of touch peripherals, such as external HID multi-touch touch screens, using unmodified drivers.
ouch device 'atmel-touchscreen' could not query the properties of its associated display 0. The device will be inoperable until the display size becomes available.
[Quote=引用 13 楼 yyhzpk 的回复:]
ouch device 'atmel-touchscreen' could not query the properties of its associated display 0. The device will be inoperable until the display size becomes available.
[Quote=引用 13 楼 yyhzpk 的回复:]
ouch device 'atmel-touchscreen' could not query the properties of its associated display 0. The device will be inoperable until the display size becomes available.
[Quote=引用 13 楼 yyhzpk 的回复:]
ouch device 'atmel-touchscreen' could not query the properties of its associated display 0. The device will be inoperable until the display size becomes available.