From mboxrd@z Thu Jan 1 00:00:00 1970 From: Srinivas KANDAGATLA Subject: Re: [PATCH 3.7.0-rc4] of/net/mdio-gpio: Fix pdev->id issue when using devicetrees. Date: Fri, 16 Nov 2012 09:54:47 +0000 Message-ID: <50A60D67.6000100@st.com> References: <1352816773-17837-1-git-send-email-srinivas.kandagatla@st.com> <20121114.185940.648295821386414260.davem@davemloft.net> Reply-To: srinivas.kandagatla@st.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20121114.185940.648295821386414260.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org To: David Miller , Grant Likely Cc: netdev@vger.kernel.org, devicetree-discuss@lists.ozlabs.org List-Id: devicetree@vger.kernel.org On 14/11/12 23:59, David Miller wrote: > From: Srinivas KANDAGATLA > Date: Tue, 13 Nov 2012 14:26:13 +0000 > >> From: Srinivas Kandagatla >> >> When the mdio-gpio driver is probed via device trees, the platform >> device id is set as -1, However the id is re-used in the code while >> creating an mdio bus. >> So, setting up the id via aliases from device tree is a sensible >> solution to fix this issue. >> >> Signed-off-by: Srinivas Kandagatla > This seems rather pointless unless you also update every single device > tree out there. > > Also you need to describe what are the ramifications of this problem > otherwise it is impossible to figure out how serious this change is. > > Does it prevent probing? Does it cause a crash? I apologies, I should have explained the full use-case. use-case is if the mac driver want to connect via phy_connect() to mdio-gpio phy it would use bus name to do so. mdio-gpio phy bus name is formated as "gpio-:. In the existing code the bus number for mdio-gpio if probed from device trees will be set to -1 which results in bus name set to "gpio-ffffffff:" which is the problem here. fffffff is result of pdev->id set to -1 which should be set to a logical number, and this is only possible via aliases. Having fffffff as bus-id also means that we can't have two mdio-gpio buses via device trees as it will result in same bus-id. This patch attempts to fix this issue. So getting the id from alias would be a right choice. I also agree with Grant's comments about setting up pdev->id. Will send v2 patch with considering Grant's comments. > > Basically, what I'm saying is that this is a very poor submission and > you need to substantially improve it and communicate better. > > If the problem is basically benign, then you should target this change > to net-next instead of the net tree, along with the necessary dt file > updates. I have looked in net-next and there are no dt files which use this driver. Thanks, srini > Thanks. > >