Currently only the drivers/pinctrl/devicetree.c code allows registering pinctrl-mappings which may later be unregistered, all other mappings are assumed to be permanent. Non-dt platforms may also want to register pinctrl mappings from code which is build as a module, which requires being able to unregister the mapping when the module is unloaded to avoid dangling pointers. To allow unregistering the mappings the devicetree code uses 2 internal functions: pinctrl_register_map and pinctrl_unregister_map. pinctrl_register_map allows the devicetree code to tell the core to not memdup the mappings as it retains ownership of them and pinctrl_unregister_map does the unregistering, note this only works when the mappings where not memdupped. The only code relying on the memdup/shallow-copy done by pinctrl_register_mappings is arch/arm/mach-u300/core.c this commit replaces the __initdata with const, so that the shallow-copy is no longer necessary. After that we can get rid of the internal pinctrl_unregister_map function and just use pinctrl_register_mappings directly everywhere. This commit also renames pinctrl_unregister_map to pinctrl_unregister_mappings so that its naming matches its pinctrl_register_mappings counter-part and exports it. Together these 2 changes will allow non-dt platform code to register pinctrl-mappings from modules without breaking things on module unload (as they can now unregister the mapping on unload).
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| @@ -153,6 +153,7 @@ struct pinctrl_map { · 152 unmodified lines | |||
| 153 | 153 | ||
| 154 | extern int pinctrl_register_mappings(const struct pinctrl_map *map, | 154 | extern int pinctrl_register_mappings(const struct pinctrl_map *map, |
| 155 | unsigned num_maps); | 155 | unsigned num_maps); |
| 156 | extern void pinctrl_unregister_mappings(const struct pinctrl_map *map); | ||
| 156 | extern void pinctrl_provide_dummies(void); | 157 | extern void pinctrl_provide_dummies(void); |
| 157 | #else | 158 | #else |
| 158 | 159 | ||
| @@ -162,6 +163,10 @@ static inline int pinctrl_register_mappings(const struct pinctrl_map *map, · 3 unmodified lines | |||
| 162 | return 0; | 163 | return 0; |
| 163 | } | 164 | } |
| 164 | 165 | ||
| 166 | static inline void pinctrl_unregister_mappings(const struct pinctrl_map *map) | ||
| 167 | { | ||
| 168 | } | ||
| 169 | |||
| 165 | static inline void pinctrl_provide_dummies(void) | 170 | static inline void pinctrl_provide_dummies(void) |
| 166 | { | 171 | { |
| 167 | } | 172 | } |