diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index 138e72f74377a2c5d034b22f9ebf32f9a83d7d34..a6386b3a3c157c2dbd01573c713b6753a1a1c972 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -43,6 +43,8 @@ struct pinctrl_maps { unsigned num_maps; }; +static bool pinctrl_dummy_state; + /* Mutex taken by all entry points */ DEFINE_MUTEX(pinctrl_mutex); @@ -61,6 +63,19 @@ static LIST_HEAD(pinctrl_maps); _i_ < _maps_node_->num_maps; \ i++, _map_ = &_maps_node_->maps[_i_]) +/** + * pinctrl_provide_dummies() - indicate if pinctrl provides dummy state support + * + * Usually this function is called by platforms without pinctrl driver support + * but run with some shared drivers using pinctrl APIs. + * After calling this function, the pinctrl core will return successfully + * with creating a dummy state for the driver to keep going smoothly. + */ +void pinctrl_provide_dummies(void) +{ + pinctrl_dummy_state = true; +} + const char *pinctrl_dev_get_name(struct pinctrl_dev *pctldev) { /* We're not allowed to register devices without name */ @@ -719,8 +734,18 @@ static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p, struct pinctrl_state *state; state = find_state(p, name); - if (!state) - return ERR_PTR(-ENODEV); + if (!state) { + if (pinctrl_dummy_state) { + /* create dummy state */ + dev_dbg(p->dev, "using pinctrl dummy state (%s)\n", + name); + state = create_state(p, name); + if (IS_ERR(state)) + return state; + } else { + return ERR_PTR(-ENODEV); + } + } return state; } diff --git a/include/linux/pinctrl/machine.h b/include/linux/pinctrl/machine.h index 9c4a19867289e195f4074ac0192abd94778be241..7d22ab00343f1575c9e6bc1c9f30d3eabe584a23 100644 --- a/include/linux/pinctrl/machine.h +++ b/include/linux/pinctrl/machine.h @@ -154,7 +154,7 @@ struct pinctrl_map { extern int pinctrl_register_mappings(struct pinctrl_map const *map, unsigned num_maps); - +extern void pinctrl_provide_dummies(void); #else static inline int pinctrl_register_mappings(struct pinctrl_map const *map, @@ -163,5 +163,8 @@ static inline int pinctrl_register_mappings(struct pinctrl_map const *map, return 0; } +static inline void pinctrl_provide_dummies(void) +{ +} #endif /* !CONFIG_PINCTRL */ #endif