[PATCH v2 2/2] usb: typec: mux: avoid duplicated mux switches

[Heikki Krogerus]

Mon, Feb 23, 2026 at 07:27:39PM +0100, Sebastian Reichel wrote:
> Some devices use combo PHYs (i.e. USB3 + DisplayPort), which also
> handle the lane muxing. These PHYs are referenced twice from
> the USB-C connector (USB super-speed lines and SBU/AUX lines)
> resulting in the mux being configured twice. Avoid this by
> dropping duplicates.
> 
> Signed-off-by: Sebastian Reichel <sebastian.reichel at collabora.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus at linux.intel.com>

> ---
>  drivers/usb/typec/mux.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
> index 9b908c46bd7d..db5e4a4c0a99 100644
> --- a/drivers/usb/typec/mux.c
> +++ b/drivers/usb/typec/mux.c
> @@ -275,7 +275,9 @@ static int mux_fwnode_match(struct device *dev, const void *fwnode)
>  static void *typec_mux_match(const struct fwnode_handle *fwnode,
>  			     const char *id, void *data)
>  {
> +	struct typec_mux_dev **mux_devs = data;
>  	struct device *dev;
> +	int i;
>  
>  	/*
>  	 * Device graph (OF graph) does not give any means to identify the
> @@ -291,6 +293,14 @@ static void *typec_mux_match(const struct fwnode_handle *fwnode,
>  	dev = class_find_device(&typec_mux_class, NULL, fwnode,
>  				mux_fwnode_match);
>  
> +	/* Skip duplicates */
> +	for (i = 0; i < TYPEC_MUX_MAX_DEVS; i++)
> +		if (to_typec_mux_dev(dev) == mux_devs[i]) {
> +			put_device(dev);
> +			return NULL;
> +		}
> +
> +
>  	return dev ? to_typec_mux_dev(dev) : ERR_PTR(-EPROBE_DEFER);
>  }
>  
> @@ -316,7 +326,8 @@ struct typec_mux *fwnode_typec_mux_get(struct fwnode_handle *fwnode)
>  		return ERR_PTR(-ENOMEM);
>  
>  	count = fwnode_connection_find_matches(fwnode, "mode-switch",
> -					       NULL, typec_mux_match,
> +					       (void **)mux_devs,
> +					       typec_mux_match,
>  					       (void **)mux_devs,
>  					       ARRAY_SIZE(mux_devs));
>  	if (count <= 0) {
> 
> -- 
> 2.51.0

-- 
heikki