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From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To:     Vinod Koul <vkoul@kernel.org>,
        Bard Liao <yung-chuan.liao@linux.intel.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        Sanyog Kale <sanyog.r.kale@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Philippe Ombredanne <pombredanne@nexb.com>,
        Takashi Iwai <tiwai@suse.de>, alsa-devel@alsa-project.org,
        linux-kernel@vger.kernel.org
Cc:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        stable@vger.kernel.org
Subject: [PATCH] soundwire: fix initializing sysfs for same devices on different buses
Date:   Wed,  4 Oct 2023 15:02:43 +0200
Message-Id: <20231004130243.493617-1-krzysztof.kozlowski@linaro.org>
MIME-Version: 1.0
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If same devices with same device IDs are present on different soundwire
buses, the probe fails due to conflicting device names and sysfs
entries:

  sysfs: cannot create duplicate filename '/bus/soundwire/devices/sdw:0:0217:0204:00:0'

The link ID is 0 for both devices, so they should be differentiated by
bus ID.  Add the bus ID so, the device names and sysfs entries look
like:

  sdw:1:0:0217:0204:00:0 -> ../../../devices/platform/soc@0/6ab0000.soundwire-controller/sdw-master-1/sdw:1:0:0217:0204:00:0
  sdw:3:0:0217:0204:00:0 -> ../../../devices/platform/soc@0/6b10000.soundwire-controller/sdw-master-3/sdw:3:0:0217:0204:00:0

Fixes: 7c3cd189b86d ("soundwire: Add Master registration")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

---

Sending as RFT, because I did not test it on that many devices and
user-spaces.
---
 drivers/soundwire/slave.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c
index c1c1a2ac293a..4db43ea53d47 100644
--- a/drivers/soundwire/slave.c
+++ b/drivers/soundwire/slave.c
@@ -39,14 +39,14 @@ int sdw_slave_add(struct sdw_bus *bus,
 	slave->dev.fwnode = fwnode;
 
 	if (id->unique_id == SDW_IGNORED_UNIQUE_ID) {
-		/* name shall be sdw:link:mfg:part:class */
-		dev_set_name(&slave->dev, "sdw:%01x:%04x:%04x:%02x",
-			     bus->link_id, id->mfg_id, id->part_id,
+		/* name shall be sdw:bus:link:mfg:part:class */
+		dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x",
+			     bus->id, bus->link_id, id->mfg_id, id->part_id,
 			     id->class_id);
 	} else {
-		/* name shall be sdw:link:mfg:part:class:unique */
-		dev_set_name(&slave->dev, "sdw:%01x:%04x:%04x:%02x:%01x",
-			     bus->link_id, id->mfg_id, id->part_id,
+		/* name shall be sdw:bus:link:mfg:part:class:unique */
+		dev_set_name(&slave->dev, "sdw:%01x:%01x:%04x:%04x:%02x:%01x",
+			     bus->id, bus->link_id, id->mfg_id, id->part_id,
 			     id->class_id, id->unique_id);
 	}
 
-- 
2.34.1