From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sipsolutions.net (s3.sipsolutions.net [168.119.38.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D255A4C77AD; Tue, 19 May 2026 12:11:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=168.119.38.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779192701; cv=none; b=Nro1WBaTI6b/myNfvxnxoil5hG3QF6BL4L5MOrMAfsDxFXvl6ztZqvr2fBimwZZ1ReseCCfGY3esqq9WKYARVNF01iFutBOgD3PGO2clzqN0ndpeIultAKMqMSxqX7xUqOdCcUbqtC2F1ACpj0eTnNufnfs+r5mOmWhh3ApVmX4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779192701; c=relaxed/simple; bh=BzPILivh8u0VPbKcKjEXQnpX2c2Ts/Bj0Ue0PAy66jM=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=mEOmtaoeDbsOecbhWBcKqwQSJ/nGo9IleLaXdQZnCO2yAl7HoQoTrJ5xCdc8ZpQFhOa+5Mtv6qr+XibsZPraT6gMSweze4hrL8Z+4AwU1NP3YH/8AEeMCnV0iiNVdelHH93INkSU23GXG6A7DF++YUBGJShadsiy7PLExJsXfxw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=permerror header.from=sipsolutions.net; spf=none smtp.mailfrom=sipsolutions.net; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b=WMk6sCbk; arc=none smtp.client-ip=168.119.38.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=permerror header.from=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b="WMk6sCbk" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=MIME-Version:Content-Transfer-Encoding: Content-Type:References:In-Reply-To:Date:Cc:To:From:Subject:Message-ID:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=Ii8DV8jwO7CRY9lsiWuhphBYKigNJYNHkFu2YjA2p4A=; t=1779192699; x=1780402299; b=WMk6sCbkgzb+GmDru/5SYDjY9GXm07/dJ8pUJEWBXFOlDtk LmREyj2tBD9njzGSAMmvQBo9oW+j6GYSQ/xrwrNApiA3jD3b0RPt/4nK61yTuHbdEo7LEf9E+J3eN 4SvJnrLd18eo1JpSDsn+ZLoX0m2P036t1L2/sRRUZ55Re8zwxj/dSFlVRJoqlgLIWFPDyzMLEfZJR ubqlGgRpL0GcoJRjIaA/7n2etvvjt4wQQxCtFpq0LpTtBSpFL+BeaIp9OSgqxyTCpJuJHdxxe3UIR S3E5qanhtPbBo6vLJKI2Th4nn7CQYZ9UpJj8FRIvKQp0y6QXgIvyUbhehBkBfJDQ==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.98.2) (envelope-from ) id 1wPJIO-00000006ZBJ-1TkK; Tue, 19 May 2026 14:11:36 +0200 Message-ID: <83ddb427597663b947c49afd835014f2bc1033f2.camel@sipsolutions.net> Subject: Re: [RFC rtw-next 1/2] wifi: rtw89: usb: add hw_info sysfs attribute From: Johannes Berg To: Ping-Ke Shih , "linux-wireless@vger.kernel.org" Cc: Johnson Tsai , driver-core@lists.linux.dev Date: Tue, 19 May 2026 14:11:32 +0200 In-Reply-To: References: <20260519072415.25746-1-pkshih@realtek.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-malware-bazaar: not-scanned Hi, > > Example usage from user-space: > > $ cat /sys/bus/usb/devices/2-3.1.2:1.0/hw_info > > SN: 36 42 00 01 23 > > UUID: aa ec 2b 7c 0a 55 47 27 8d e0 b3 0f eb cc bb aa Sysfs has a "one value per file" rule (soft rule according to the docs, but harder in practice, I believe), so seems if anything that should be two files. Maybe a UUID should also be formatted as such with %pU or similar. > I also looked up lore.kernel.org and only found a thread commented by Kal= le [1]. > However, it is not clear to us if sysfs is suitable to read efuse SN/UUID= . >=20 > [1] https://lore.kernel.org/linux-wireless/87ziib3da5.fsf@kamboji.qca.qua= lcomm.com/ It seems to me this was more in the context of _writable_ files to do some operations. I don't think I have a problem with this, but sysfs also has documentation requirements, and we should probably ask driver-core@lists.linux.dev. I'm not really quite sure I see the _point_ of identifying the serial number of a wifi device in a container, but I guess you do. johannes