接前一篇文章:DRM全解析 —— CRTC详解(1)
本文继续对DRM中CRTC的核心结构struct drm_crtc的成员进行释义。
3. drm_crtc结构释义
(5)struct drm_modeset_lock mutex
/**
* @mutex:
*
* This provides a read lock for the overall CRTC state (mode, dpms
* state, ...) and a write lock for everything which can be update
* without a full modeset (fb, cursor data, CRTC properties ...). A full
* modeset also need to grab &drm_mode_config.connection_mutex.
*
* For atomic drivers specifically this protects @state.
*/
struct drm_modeset_lock mutex;
此项为整个CRTC状态(mode、dpms state……)提供了读取锁,并为所有可以在没有完整modeset的情况下更新的内容(fb、c