below is additional comments. daeinki 쓴 글: > Hi all, > > I'm writing Samsung SoC based DRM framework and this one includes FIMD > and HDMI driver as hardware dependent modules. and for now, encoder, > connector, crtc and fb module has been materialized almost. but I'm > contending with framebuffer setting issue(created fb_info should be > registered to linux framebuffer through register_framebuffer() or not)as > default framebuffer at booting time. > > at drm_fb_helper_single_fb_probe() of drm_fb_helper.c file, fb_helper's > fb_probe callback is called and this one creates new framebuffer and > returns a value more then 0 if true. internally, this process creates an > fb_info object and drm_framebuffer and then drm_framebuffer would be > added to mode_config.fb_list of the drm_device. > it's my mistake. return value is 0 if true, nonzero otherwise. > a value returned, new_fb is used to decide that it calls > register_framebuffer() or drm_fb_helper_set_par(). at this point, I am > confused it's a good way to call register_framebuffer() otherwise > drm_fb_helper_set_par(). if register_framebuffer() is called then I > guess drm_fb_helper_set_par() or drm_crtc_helper_set_config() should be > called somewhere subsequently to apply this one to real hardware because > previous process is just for maintaining data logically.(not set up data > to h/w) > > it's a right way to call register_framebuffer() and then > drm_fb_helper_set_par() or drm_crtc_helper_set_config()? otherwise just > only drm_fb_helper_set_par() or drm_crtc_helper_set_config() ignoring > register_framebuffer()? and what is the purpose of using > register_framebuffer()? > I understood that if fb_probe() callback is fail then fb_info object is registered to linux framebuffer through register_framebuffer() otherwise(if true) hardware configuration would be completed by drm_fb_helper_set_par() so the reason of using register_framebuffer() is that the case of failing fb_probe() callback, it is for drawing on only linux framebuffer. is it right? > In my case, first, register_framebuffer() is called and then if desired > default crtc id is matched with drm_fb_helper->crtc_info[0 ~ n].crtc_id, > it gets mode_set of drm_fb_helper->crtc_info[n] and then it calls > drm_crtc_helper_set_config(mode_set). at this time, all the hardware > configurations would be completed. > > thank you in advance. > > Best Regards > Inki Dae. > -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
