Re: [PATCH v4 2/7] usb: typec: mux: Add CONFIG guards for functions

[Heikki Krogerus]

On Wed, Jun 15, 2022 at 05:20:18PM +0000, Prashant Malani wrote:
> There are some drivers that can use the Type C mux API, but don't have
> to. Introduce CONFIG guards for the mux functions so that drivers can
> include the header file and not run into compilation errors on systems
> which don't have CONFIG_TYPEC enabled. When CONFIG_TYPEC is not enabled,
> the Type C mux functions will be stub versions of the original calls.
> 
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reviewed-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
> Tested-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
> Signed-off-by: Prashant Malani <pmalani@xxxxxxxxxxxx>

Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

> ---
> 
> Changes since v3:
> - No changes.
> 
> Changes since v2:
> - Fix up return types for some of the stubs. Remove 1 unnecessary stub
>   in the else condition.
> - Remove unnecessary IS_MODULE config guard.
> - Added Reviewed-by and Tested-by tags.
> 
> Changes since v1:
> - Added static inline to stub functions.
> - Updated function signature of stub functions from "struct typec_mux"
>   to "struct typec_mux_dev" in accordance with updates from commit
>   713fd49b430c ("usb: typec: mux: Introduce indirection")
> 
>  include/linux/usb/typec_mux.h | 44 ++++++++++++++++++++++++++++++-----
>  1 file changed, 38 insertions(+), 6 deletions(-)
> 
> diff --git a/include/linux/usb/typec_mux.h b/include/linux/usb/typec_mux.h
> index ee57781dcf28..9292f0e07846 100644
> --- a/include/linux/usb/typec_mux.h
> +++ b/include/linux/usb/typec_mux.h
> @@ -58,17 +58,13 @@ struct typec_mux_desc {
>  	void *drvdata;
>  };
>  
> +#if IS_ENABLED(CONFIG_TYPEC)
> +
>  struct typec_mux *fwnode_typec_mux_get(struct fwnode_handle *fwnode,
>  				       const struct typec_altmode_desc *desc);
>  void typec_mux_put(struct typec_mux *mux);
>  int typec_mux_set(struct typec_mux *mux, struct typec_mux_state *state);
>  
> -static inline struct typec_mux *
> -typec_mux_get(struct device *dev, const struct typec_altmode_desc *desc)
> -{
> -	return fwnode_typec_mux_get(dev_fwnode(dev), desc);
> -}
> -
>  struct typec_mux_dev *
>  typec_mux_register(struct device *parent, const struct typec_mux_desc *desc);
>  void typec_mux_unregister(struct typec_mux_dev *mux);
> @@ -76,4 +72,40 @@ void typec_mux_unregister(struct typec_mux_dev *mux);
>  void typec_mux_set_drvdata(struct typec_mux_dev *mux, void *data);
>  void *typec_mux_get_drvdata(struct typec_mux_dev *mux);
>  
> +#else
> +
> +static inline struct typec_mux *fwnode_typec_mux_get(struct fwnode_handle *fwnode,
> +				       const struct typec_altmode_desc *desc)
> +{
> +	return NULL;
> +}
> +
> +static inline void typec_mux_put(struct typec_mux *mux) {}
> +
> +static inline int typec_mux_set(struct typec_mux *mux, struct typec_mux_state *state)
> +{
> +	return 0;
> +}
> +
> +static inline struct typec_mux_dev *
> +typec_mux_register(struct device *parent, const struct typec_mux_desc *desc)
> +{
> +	return ERR_PTR(-EOPNOTSUPP);
> +}
> +static inline void typec_mux_unregister(struct typec_mux_dev *mux) {}
> +
> +static inline void typec_mux_set_drvdata(struct typec_mux_dev *mux, void *data) {}
> +static inline void *typec_mux_get_drvdata(struct typec_mux_dev *mux)
> +{
> +	return ERR_PTR(-EOPNOTSUPP);
> +}
> +
> +#endif /* CONFIG_TYPEC */
> +
> +static inline struct typec_mux *
> +typec_mux_get(struct device *dev, const struct typec_altmode_desc *desc)
> +{
> +	return fwnode_typec_mux_get(dev_fwnode(dev), desc);
> +}
> +
>  #endif /* __USB_TYPEC_MUX */
> -- 
> 2.36.1.476.g0c4daa206d-goog

-- 
heikki