Re: [PATCH v3 00/11] driver core: Constify API device_find_child()

[Zijun Hu <zijun_hu@icloud.com>]

On 2024/12/5 08:10, Zijun Hu wrote:
> This patch series is to constify the following API:

This patch series is based on the lasted mainline commit
Commit: feffde684ac2 ("Merge tag 'for-6.13-rc1-tag' of
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux")
to avoid potential conflict as much as possible.

> struct device *device_find_child(struct device *dev, void *data,
> 		int (*match)(struct device *dev, void *data));
> To :
> struct device *device_find_child(struct device *dev, const void *data,
> 				 device_match_t match);
> typedef int (*device_match_t)(struct device *dev, const void *data);
> 
> Why to constify the API?
> 
> - Protect caller's match data @*data which is for comparison and lookup
>   and the API does not actually need to modify @*data.
> 
> - Make the API's parameters (@match)() and @data have the same type as
>   all of other device finding APIs (bus|class|driver)_find_device().
> 
> - All kinds of existing device matching functions can be directly taken
>   as the API's argument, they were exported by driver core.
> 
> What to do?
> 
> - Patches [1/11, 3/11] prepare for constifying the API.
> 
> - Patch 4/11 constifies the API and adapt for its various subsystem usages.
> 
> - Remaining do cleanup for several usages with benefits brought above.