linux-kernel - Re: [PATCH v1 1/2] usb: typec: mux: Clean up mux_fwnode

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Message-ID: <20230525032530.u5jecuucmdrsuroo@ripper>
Date:   Wed, 24 May 2023 20:25:30 -0700
From:   Bjorn Andersson <andersson@...nel.org>
To:     Heikki Krogerus <heikki.krogerus@...ux.intel.com>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        chrome-platform@...ts.linux.dev, linux-usb@...r.kernel.org,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v1 1/2] usb: typec: mux: Clean up mux_fwnode_match()

On Wed, May 24, 2023 at 03:29:00PM +0300, Heikki Krogerus wrote:
> Removing the "svid" and "accessory" device property checks.
> Those properties are not supported on any platform.
> 
> Signed-off-by: Heikki Krogerus <heikki.krogerus@...ux.intel.com>
> Link: https://lore.kernel.org/lkml/20230522215348.uoyboow26n2o3tel@ripper/
> Cc: Bjorn Andersson <andersson@...nel.org>
> ---
>  drivers/usb/typec/mux.c | 55 ++++++-----------------------------------
>  1 file changed, 7 insertions(+), 48 deletions(-)
> 
> diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
> index d9eaf9a0b0bfd..089c2fd478318 100644
> --- a/drivers/usb/typec/mux.c
> +++ b/drivers/usb/typec/mux.c
> @@ -265,60 +265,19 @@ 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)
>  {
> -	const struct typec_altmode_desc *desc = data;
>  	struct device *dev;
> -	bool match;
> -	int nval;
> -	u16 *val;
> -	int ret;
> -	int i;
>  
>  	/*
> -	 * Check has the identifier already been "consumed". If it
> -	 * has, no need to do any extra connection identification.
> +	 * Device graph (OF graph) does not give any means to identify the
> +	 * device type or the device class of the remote port parent that @fwnode
> +	 * represents, so in order to identify the type or the class of @fwnode
> +	 * an additional device property is needed. With typec switches the

s/switches/muxes/

> +	 * property is named "orientation-switch" (@id). The value of the device

s/orientation-switch/mode-switch/

With that:

Reviewed-by: Bjorn Andersson <andersson@...nel.org>
Tested-by: Bjorn Andersson <andersson@...nel.org>

Thank you,
Bjorn

> +	 * property is ignored.
>  	 */
> -	match = !id;
> -	if (match)
> -		goto find_mux;
> -
> -	if (!desc) {
> -		/*
> -		 * Accessory Mode muxes & muxes which explicitly specify
> -		 * the required identifier can avoid SVID matching.
> -		 */
> -		match = fwnode_property_present(fwnode, "accessory") ||
> -			fwnode_property_present(fwnode, id);
> -		if (match)
> -			goto find_mux;
> -		return NULL;
> -	}
> -
> -	/* Alternate Mode muxes */
> -	nval = fwnode_property_count_u16(fwnode, "svid");
> -	if (nval <= 0)
> +	if (id && !fwnode_property_present(fwnode, id))
>  		return NULL;
>  
> -	val = kcalloc(nval, sizeof(*val), GFP_KERNEL);
> -	if (!val)
> -		return ERR_PTR(-ENOMEM);
> -
> -	ret = fwnode_property_read_u16_array(fwnode, "svid", val, nval);
> -	if (ret < 0) {
> -		kfree(val);
> -		return ERR_PTR(ret);
> -	}
> -
> -	for (i = 0; i < nval; i++) {
> -		match = val[i] == desc->svid;
> -		if (match) {
> -			kfree(val);
> -			goto find_mux;
> -		}
> -	}
> -	kfree(val);
> -	return NULL;
> -
> -find_mux:
>  	dev = class_find_device(&typec_mux_class, NULL, fwnode,
>  				mux_fwnode_match);
>  
> -- 
> 2.39.2
>