linux-kernel - [PATCH v2 1/2] usb: typec: mux: Clean up mux_fwnode

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Message-Id: <20230526131434.46920-2-heikki.krogerus@linux.intel.com>
Date:   Fri, 26 May 2023 16:14:33 +0300
From:   Heikki Krogerus <heikki.krogerus@...ux.intel.com>
To:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Cc:     Bjorn Andersson <andersson@...nel.org>,
        chrome-platform@...ts.linux.dev, linux-usb@...r.kernel.org,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH v2 1/2] usb: typec: mux: Clean up mux_fwnode_match()

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/
Reviewed-by: Bjorn Andersson <andersson@...nel.org>
Tested-by: Bjorn Andersson <andersson@...nel.org>
---
v2: Fixed the comment as requested by Bjorn.

 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..f2eee6322815d 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 muxes the
+	 * property is named "mode-switch" (@id). The value of the device
+	 * 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