Fix build issues with Linux v6.8 and later #39
Conversation
There was a problem hiding this comment.
Improve the git commit messages.
Read https://cbea.ms/git-commit/ carefully and refine.
fb.c
Outdated
| @@ -402,7 +402,7 @@ int vcamfb_init(struct vcam_device *dev) | |||
| info->fbops = &vcamfb_ops; | |||
| info->par = dev; | |||
| info->pseudo_palette = NULL; | |||
| info->flags = FBINFO_FLAG_DEFAULT; | |||
| info->flags = 0; | |||
There was a problem hiding this comment.
Do you set the flags properly?
There was a problem hiding this comment.
Below is a commit of the Linux DRM subsystem which deals with the removal of the FBINFO_FLAG_DEFAULT macro:
torvalds/linux@40e324e
According to the commit above, the default value of fb_info.flags will be set properly using framebuffer_alloc(), which is zero in the current Linux version. So I assumed that fb_info.flags can be set to zero at initialization.
But for better portability, I think I should use framebuffer_alloc() to initialize the value of fb_info.flags instead of explicitlly setting it to zero. I will modify the code and commit it.
There was a problem hiding this comment.
Good. Always address the rationale in comments or git commit messages.
|
It is meaningless to say something like
The compiler is not related to the changes by Linux kernel internally. You should analyze the upstream changes for the considerations and/or impacts. |
The field 'min_buffers_needed' in vb2_queue was renamed to 'min_queued_buffers' in Linux kernel v6.8. As a result, the field name needs to be updated when building the driver on newer kernel versions. For backward compatibility, #if and #else macros have been added to select the correct field name based on the kernel version.
The reason to do such changes is that the flag FBINFO_DEFAULT has been removed from the Linux kernel since v6.6, which was the default value of fb_info.flags. To initialize the fb_info structure (and the value of fb_info.flags) correctly without using FBINFO_DEFAULT, the framebuffer_alloc() function provided by the Linux kernel should be used. Since framebuffer_alloc() only accepts pointer to fb_info, the type of the info field in struct vcamfb_info was changed from 'struct fb_info' to 'pointer to struct fb_info'. As a result, framebuffer_release() was added to deallocate the memory pointed to by the info field. Additionally, several changes were made to accommodate the change of the info field's type.
I've updated the commit messages. |
|
Thank @hungyuhang for contributing! |
Rename
min_buffers_neededmember instruct vb2_queuetomin_queued_buffersaccording to the changes in Linux v6.8.(The change described above in the Linux Kernel source code can be viewed at: torvalds/linux@80c2b40)
Remove
FBINFO_FLAG_DEFAULTflag, as this flag was removed in Linux v6.6 and later.(The change described above in the Linux Kernel source code can be viewed at: torvalds/linux@0444fa3)