From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        Vinod Koul <vkoul@kernel.org>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.10 411/575] soundwire: debugfs: use controller id and link_id for debugfs
Date:   Mon, 15 Nov 2021 18:02:16 +0100
Message-Id: <20211115165357.975343856@linuxfoundation.org>
In-Reply-To: <20211115165343.579890274@linuxfoundation.org>
References: <20211115165343.579890274@linuxfoundation.org>
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From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

[ Upstream commit 75eac387a2539aa6c6bbee3affa23435f2096396 ]

link_id can be zero and if we have multiple controller instances
in a system like Qualcomm debugfs will end-up with duplicate namespace
resulting in incorrect debugfs entries.

Using bus-id and link-id combination should give a unique debugfs directory
entry and should fix below warning too.
"debugfs: Directory 'master-0' with parent 'soundwire' already present!"

Fixes: bf03473d5bcc ("soundwire: add debugfs support")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210907105332.1257-1-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/soundwire/debugfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/soundwire/debugfs.c b/drivers/soundwire/debugfs.c
index b6cad0d59b7b9..49900cd207bc7 100644
--- a/drivers/soundwire/debugfs.c
+++ b/drivers/soundwire/debugfs.c
@@ -19,7 +19,7 @@ void sdw_bus_debugfs_init(struct sdw_bus *bus)
 		return;
 
 	/* create the debugfs master-N */
-	snprintf(name, sizeof(name), "master-%d", bus->link_id);
+	snprintf(name, sizeof(name), "master-%d-%d", bus->id, bus->link_id);
 	bus->debugfs = debugfs_create_dir(name, sdw_debugfs_root);
 }
 
-- 
2.33.0