From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH 2/4] i3c: master: Check if devices have i3c_dev_boardinfo on i3c_master_add_i3c_dev_locked() Date: Thu, 29 Aug 2019 18:15:20 +0200 Message-ID: <20190829181520.0b33b642@collabora.com> References: <3e21481ddf53ea58f5899df6ec542b79b8cbcd68.1567071213.git.vitor.soares@synopsys.com> <20190829124457.3a750932@collabora.com> <20190829163918.571fd0d8@collabora.com> <20190829163941.45380b19@collabora.com> <20190829172441.3a76385e@collabora.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Vitor Soares Cc: "linux-kernel@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-i3c@lists.infradead.org" , "bbrezillon@kernel.org" , "robh+dt@kernel.org" , "mark.rutland@arm.com" , "Joao.Pinto@synopsys.com" List-Id: devicetree@vger.kernel.org On Thu, 29 Aug 2019 15:57:32 +0000 Vitor Soares wrote: > -----Original Message----- > From: Boris Brezillon > > Sent: Thursday, August 29, 2019 4:25 > PM > To: Vitor Soares > Cc: > linux-kernel@vger.kernel.org; devicetree@vger.kernel.org; > linux-i3c@lists.infradead.org; bbrezillon@kernel.org; robh+dt@kernel.org; > mark.rutland@arm.com; Joao.Pinto@synopsys.com > Subject: Re: [PATCH 2/4] > i3c: master: Check if devices have i3c_dev_boardinfo on > i3c_master_add_i3c_dev_locked() > > On Thu, 29 Aug 2019 15:07:08 +0000 > Vitor Soares wrote: > > > From: Boris Brezillon > > > Date: Thu, Aug 29, 2019 at 15:39:41 > > > > > > On Thu, 29 Aug 2019 16:39:18 +0200 > > > Boris Brezillon wrote: > > > > > > > On Thu, 29 Aug 2019 14:00:44 +0000 > > > > Vitor Soares wrote: > > > > > > > > > Hi Boris, > > > > > > > > > > From: Boris Brezillon > > > > > Date: Thu, Aug 29, 2019 at 11:44:57 > > > > > > > > > > > On Thu, 29 Aug 2019 12:19:33 +0200 > > > > > > Vitor Soares wrote: > > > > > > > > > > > > > The I3C devices described in DT might not be attached to the master which > > > > > > > doesn't allow to assign a specific dynamic address. > > > > > > > > > > > > I remember testing this when developing the framework, so, unless > > > > > > another patch regressed it, it should already work. I suspect patch 1 > > > > > > is actually the regressing this use case. > > > > > > > > > > For today it doesn't address the case where the device is described with > > > > > static address = 0, which isn't attached to the controller. > > > > > > > > Hm, I'm pretty sure I had designed the code to support that case (see > > > > [1]). It might be buggy, but nothing we can't fix I guess. > > > > > > > > > > [1]https://urldefense.proofpoint.com/v2/url?u=https-3A__elixir.bootlin.com_linux_v5.3-2Drc6_source_drivers_i3c_master.c-23L1898&d=DwICAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=qVuU64u9x77Y0Kd0PhDK_lpxFgg6PK9PateHwjb_DY0&m=IXS1ygIgEo5vwajk0iwd5aBDVBzRnVTjO3cg4iBmGNc&s=HC-AcYm-AZPrUBoALioej_BDnqOtJHltr39Z2yPkuU4&e= > > > > That is only valid if you have olddev which will only exist if static > > address != 0. > > Hm, if you revert patch 1 (and assuming the device is properly defined > in the DT), you should have olddev != NULL when reaching that point. If > that's not the case there's a bug somewhere that should be fixed. > > No, because the device is not attached. Oh, my bad, I see what you mean now. This is definitely a bug and should have the Fixes tags. I mean, even if we don't care about dynamic address assignment, I3C drivers might care about the ->of_node that's attached to the device.