From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1EE6C1C84AB; Fri, 1 May 2026 14:29:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777645750; cv=none; b=KG4LacxPfdd4zgg8EDkr0NSkQWFLnvZaOuOvJiVkfWLCZdeJXsc/gVQH4Ihm9EqiSumeEj/fV+PLFNksUFwIOObkk6g6PfSYoXwL8+bt4rl3IeX7/Vl3ONPPD0yWqt7CgxqMvUl/cUkeTfGB/5d3uZ0nwG3OgsIayIP/LS5zRHw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777645750; c=relaxed/simple; bh=rZeYrXuy/lw8ZEd3MCYUa+x+GsP9QlIkHRZD/cvF3Ew=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PmD2V8LuYutflb1PIhUlVviGFJhIbNKe3I2QGTGgQydrxzOkgKqLNFznuTMZGMCYOd3ZeVdDDujsOGBAd3iyqWM3T71plt+fKBMq8otAcO+XRiWpMX37b3Lld2FRPXexTm1xe+CyoOyOiTpz6ZDc1LIHrxacWysj6odZtTEYCBc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qnnwATHD; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="qnnwATHD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ADEB2C2BCB9; Fri, 1 May 2026 14:29:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777645750; bh=rZeYrXuy/lw8ZEd3MCYUa+x+GsP9QlIkHRZD/cvF3Ew=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qnnwATHDDC4drElmEdb/KEvQGvzZgviwX7f1JePNfzJxustgYZe799vQQo3ww2PrD AHpssSeaKL2Xd2+N6E7C8A3xgxEROe0ZP+y1YkkHelkdN6Zl5ackE8potUtxfVmdYp 9atFCbqPq+Os/VgstUddbnKK+0oR02Q8XE9/mIxIryTSKVZ/1go5W8vdul1bvJZjxG ENY+UKYfAl6leor/74c1NpY9SijbPwX/wab1Pv71ZlBLwmnDiYRk2Os+Z1QNDeiBrk h4CtjGfGnVPhCrNvR8cewrGlX32BaHkt4QwB2myXQMpzo2L0+D9k1O9M71FF64L7si 4mQHX1cdt4h4w== Date: Fri, 1 May 2026 15:29:05 +0100 From: Simon Horman To: Alex Cheema Cc: oliver@neukum.org, bjorn@mork.no, oleavr@frida.re, kuba@kernel.org, pabeni@redhat.com, davem@davemloft.net, edumazet@google.com, andrew+netdev@lunn.ch, netdev@vger.kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next] net: usb: cdc_ncm: add Apple Mac USB-C direct networking quirk Message-ID: <20260501142905.GH15617@horms.kernel.org> References: <20260429175739.34426-1-alex@exolabs.net> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260429175739.34426-1-alex@exolabs.net> On Wed, Apr 29, 2026 at 06:57:39PM +0100, Alex Cheema wrote: > Apple Silicon Macs expose two CDC NCM "private" data interfaces over > USB-C with VID:PID 0x05ac:0x1905 and product string "Mac". This is the > same protocol Apple already ships on iPhone (0x05ac:0x12a8) and iPad > (0x05ac:0x12ab) for RemoteXPC since iOS 17 -- both data interfaces lack > an interrupt status endpoint, so they rely on the FLAG_LINK_INTR- > conditional bind path introduced in commit 3ec8d7572a69 ("CDC-NCM: add > support for Apple's private interface"). > > The id_table currently has entries for iPhone and iPad but not for the > Mac. Without a match, cdc_ncm falls through to the generic CDC NCM > class-match entry, which uses the FLAG_LINK_INTR-having cdc_ncm_info > struct, so bind_common() fails on the missing status endpoint and no > netdev appears. > > Add id_table entries for both interface numbers (0 and 2) of the Mac, > bound to the existing apple_private_interface_info driver_info. > > Verified empirically on a Mac Studio M3 Ultra running macOS 26.5: when > a Mac is connected via USB-C, ioreg shows VID 0x05ac, PID 0x1905, > product string "Mac", with two NCM data interfaces at numbers 0 and 2. > The same PID is presented by all current Apple Silicon Mac models > (MacBook Pro/Air, Mac mini, Mac Studio across the M-series), mirroring > Apple's single-PID-per-family pattern from iPhone/iPad. > > After this patch, plugging a Mac into a Linux host running the patched > kernel produces two enx... interfaces (one per data interface), > "ip -br link" lists them as UP, and standard userspace networking > (DHCP, NetworkManager shared mode, etc.) works without any modprobe > overrides or out-of-tree modules. > > Signed-off-by: Alex Cheema Reviewed-by: Simon Horman