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 0C06263CB; Sun, 10 May 2026 02:25:24 +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=1778379925; cv=none; b=VYNBMYSQ5yCZIX+afyPaDhFPED4GwsworXwI7soW4z2isHHpgA9Gr49zwwJF3FMi4t+2tKYpnyi7ss8dykUJyNVpOtVb/pEcf6tp8T7LP2sxOcP+EaM23UpgvbKAV8DZmP5epr7FIPUs3yCA/JcM6gV4M8MzTPD0kSRIeb/yta8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778379925; c=relaxed/simple; bh=DuPHI1LqOFfQCPwSGvE4XxVWrva8Uk84ODEwZHi72xU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qDthOCx1hjB4wtUbH7QD+lhf7laJs3isYUsV3b3L1hoeQEgpV433gt0fFA2if/beEMC2+EmfPzx7fcPnLVYaR1+okP72/SU3Jyo+fxZ6A+uEVz+oPVhZFfM3tcOdBIhp0geQGDdWmQOmKEHxKFeJmJqJyk9RMi7sKhntecFsmX0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=e79y6hL/; 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="e79y6hL/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8DAE5C2BCC7; Sun, 10 May 2026 02:25:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778379924; bh=DuPHI1LqOFfQCPwSGvE4XxVWrva8Uk84ODEwZHi72xU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=e79y6hL/mgDvOZD8UHrjx/yvvGE14Vi42uRup1vVa+BwGGuz0tI3FboKrX6KCcHYW RzREP9nAcxXgbOLsICt59PEujBZfc43refGEy/MqJqsWO96s+Q3AgEvXjdaDOJlAAS iXt5onlnEIiRTPA221E7iqjKkNnVa/ou5prZT51yvrxvmamwRnnTONClO46LkwR6wZ t2IFlN52kGo0lvKsca1tHoXbtX8d3ZNYB/HRYPyRw5jkTtawLddwbKxR+1rJEj3vIi eoZSgqm4WxQI4AKYACjQH26b7yHJFcZfpkAvmuGCkgkL1k/4LZuGB+A3395nol8DbQ i0nDH3HyM9r4g== Date: Sat, 9 May 2026 21:25:16 -0500 From: Bjorn Andersson To: Alex Elder Cc: andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, maxime.chevallier@bootlin.com, rmk+kernel@armlinux.org.uk, konradybcio@kernel.org, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, linusw@kernel.org, brgl@kernel.org, arnd@arndb.de, gregkh@linuxfoundation.org, Daniel Thompson , mohd.anwar@oss.qualcomm.com, a0987203069@gmail.com, alexandre.torgue@foss.st.com, ast@kernel.org, boon.khai.ng@altera.com, chenchuangyu@xiaomi.com, chenhuacai@kernel.org, daniel@iogearbox.net, hawk@kernel.org, hkallweit1@gmail.com, inochiama@gmail.com, john.fastabend@gmail.com, julianbraha@gmail.com, livelycarpet87@gmail.com, matthew.gerlach@altera.com, mcoquelin.stm32@gmail.com, me@ziyao.cc, prabhakar.mahadev-lad.rj@bp.renesas.com, richardcochran@gmail.com, rohan.g.thomas@altera.com, sdf@fomichev.me, siyanteng@cqsoftware.com.cn, weishangjuan@eswincomputing.com, wens@kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-gpio@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next 08/12] dt-bindings: net: toshiba,tc965x-dwmac: add TC956x Ethernet bridge Message-ID: References: <20260501155421.3329862-1-elder@riscstar.com> <20260501155421.3329862-9-elder@riscstar.com> <3c78f48c-6478-46d0-87c2-581bb58637dd@riscstar.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <3c78f48c-6478-46d0-87c2-581bb58637dd@riscstar.com> On Thu, May 07, 2026 at 01:37:09PM -0500, Alex Elder wrote: > On 5/7/26 9:12 AM, Bjorn Andersson wrote: > > On Fri, May 01, 2026 at 10:54:16AM -0500, Alex Elder wrote: > > > diff --git a/Documentation/devicetree/bindings/net/toshiba,tc956x-dwmac.yaml b/Documentation/devicetree/bindings/net/toshiba,tc956x-dwmac.yaml > > [..] > > > + > > > + gpio-controller: true > > > > I don't have any concern with the use of a proper gpio driver to model > > the implementation, but if I understand correctly this relationship > > between gpio controller and gpio consumer is strictly internal to "the > > PCI device". > > (I think you're already cool with this but I still wanted to respond.) > Thank you for the further clarifications, and added details, Alex. This does look reasonable to me. Regards, Bjorn > That is not correct. These GPIO lines are used two ways for the > RB3gen2: > - drivers/pci/pwrctrl/pci-pwrctrl-tc9563.c uses GPIOs 2 and 3 to > assert/deassert the reset lines associated with the two exposed > downstream PCIe ports on the PCIe switch within the TC956x. > > - Each of the Ethernet PHYs has a reset GPIO. On the RB3gen2, the > GPIOs used for the purpose come from the GPIO controller embedded > in the TC9564 (00 and 01). > > These are therefore "exposed" (they are *not* strictly internal). > > > Is this connection variable or is the link merely expressed in > > DeviceTree to mitigate the fact that you choose to implement the > > responsibilities of the two parts split into two device drivers? > > It is variable. These resets might be implemented by other GPIO > controllers on other platforms. > > > Are there other consumers of these TC956x gpios which would result in a > > board designer (and hence dts author) to ever reference this > > gpio-controller in a different way? > > They could. Nine of these GPIOs are exposed by the TC956x pins > (GPIO00-06, GPIO12, GPIO35 and GPIO36). The RB3gen2 uses 00-03 > (and possibly 04 but that's for a PHY we haven't tested yet). > > -Alex > > > Regards, > > Bjorn >