From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751368Ab3LKJIT (ORCPT ); Wed, 11 Dec 2013 04:08:19 -0500 Received: from bear.ext.ti.com ([192.94.94.41]:44337 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750736Ab3LKJII (ORCPT ); Wed, 11 Dec 2013 04:08:08 -0500 Message-ID: <52A82B44.10408@ti.com> Date: Wed, 11 Dec 2013 14:37:16 +0530 From: Kishon Vijay Abraham I User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Heikki Krogerus , CC: , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v3 04/10] usb: dwc3: use quirks to know if a particualr platform doesn't have PHY References: <1385373690-12170-1-git-send-email-kishon@ti.com> <1385373690-12170-5-git-send-email-kishon@ti.com> <20131204144027.GB21055@xps8300> <52A01E86.50406@ti.com> <20131205075828.GA32583@xps8300> <52A56DA1.1010808@ti.com> <20131209092604.GC5231@xps8300> <20131211085320.GD28456@xps8300> In-Reply-To: <20131211085320.GD28456@xps8300> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 11 December 2013 02:23 PM, Heikki Krogerus wrote: > Hi, > > On Mon, Dec 09, 2013 at 11:26:04AM +0200, Heikki Krogerus wrote: >>>>>> Can you guys explain why is something like this needed? Like with >>>>>> clocks and gpios, the device drivers shouldn't need to care any more >>>>>> if the platform has the phys or not. -ENODEV tells you your platform >>>>> >>>>> Shouldn't we report if a particular platform needs a PHY and not able to get >>>>> it. How will a user know if a particular controller is not working because it's >>>>> not able to get and initialize the PHYs? Don't you think in such cases it's >>>>> better to fail (and return from probe) because the controller will not work >>>>> anyway without the PHY? >>>> >>>> My point is that you do not need to separately tell this to the driver >>>> like you do with the quirks (if you did, then you would need to fix >>>> your framework and not hack the drivers). >>>> >>>> Like I said, ENODEV tells you that there is no phy on this platform >>>> for you, allowing you to safely continue. If your phy driver is not >>>> loaded, the framework already returns EPROBE_DEFER, right. Any other >>> >>> right. but that doesn't consider broken dt data. With quirks we'll >>> able to tell if a controller in a particular platform has PHY or not >>> without depending on the dt data. >> >> Broken dt data? What kind of scenario are you thinking here? Do you >> mean case where the dt does not describe the phy on a platform that >> depends on it? Shouldn't that problem be fixed in the dt and not >> hacked in the drivers? Or are you thinking about something else? >> >> Is there a case where something like that is actually happening? > > I'm guessing I'm not getting an answer to this one. > > Look, this patch will not work with ACPI enumerated devices. We will > have a platform providing a single ACPI id, but there is a whole bunch > of boards based on it and we have no way of telling which of them > need/have phys to deal with and which ones don't. Alright.. I'll drop this patch then. Thanks Kishon