Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753770Ab3GQJzv (ORCPT ); Wed, 17 Jul 2013 05:55:51 -0400 Received: from hqemgate04.nvidia.com ([216.228.121.35]:11212 "EHLO hqemgate04.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753610Ab3GQJzt (ORCPT ); Wed, 17 Jul 2013 05:55:49 -0400 X-PGP-Universal: processed; by hqnvupgp08.nvidia.com on Wed, 17 Jul 2013 02:53:52 -0700 Message-ID: <51E669EE.6000705@nvidia.com> Date: Wed, 17 Jul 2013 17:54:54 +0800 From: Wei Ni User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130623 Thunderbird/17.0.7 MIME-Version: 1.0 To: Jean Delvare CC: Guenter Roeck , Thierry Reding , "rui.zhang@intel.com" , "lm-sensors@lm-sensors.org" , "linux-pm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-tegra@vger.kernel.org" Subject: Re: [PATCH v3 1/4] hwmon: (lm90) split set&show temp as common codes References: <1373615287-18502-1-git-send-email-wni@nvidia.com> <1373615287-18502-2-git-send-email-wni@nvidia.com> <20130712152615.23464a6b@endymion.delvare> <20130712135000.GA3386@roeck-us.net> <20130712163034.1fc1cd66@endymion.delvare> <20130712144011.GC3629@roeck-us.net> <51E395D9.6070000@nvidia.com> <20130715092415.6d082aa2@endymion.delvare> <20130717042618.GA11359@mithrandir> <20130717051409.GA16413@roeck-us.net> <51E6392E.5080906@nvidia.com> <20130717111144.491e9958@endymion.delvare> In-Reply-To: <20130717111144.491e9958@endymion.delvare> 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 Content-Length: 2798 Lines: 66 On 07/17/2013 05:11 PM, Jean Delvare wrote: > On Wed, 17 Jul 2013 14:26:54 +0800, Wei Ni wrote: >> On 07/17/2013 01:14 PM, Guenter Roeck wrote: >>> On Wed, Jul 17, 2013 at 06:26:20AM +0200, Thierry Reding wrote: >>>> On Mon, Jul 15, 2013 at 09:24:15AM +0200, Jean Delvare wrote: >>>>> On Mon, 15 Jul 2013 14:25:29 +0800, Wei Ni wrote: >>>>>> I think we can decide it in the DT, we can add a dt property in the lm90 >>>>>> device node, such as: >>>>>> sys-interface = SYS_HWMON; >>>>>> or >>>>>> sys-interface = SYS_THERMAL; >>>>>> So we register it as the hwmon or thermal device >>>>> >>>>> This is an option, but please keep in mind that DT is not the only way >>>>> to instantiate LM90-like devices, and we should not expose duplicate >>>>> inputs by default. It is fine with me if the default is to create only a >>>>> HWMON device (as the lm90 driver was doing so far), and only >>>>> DT-instantiated devices have the choice. >>>> >>>> I don't think this information belongs in the device tree. Whether the >>>> device is exposed as hwmon or thermal device (or both) is entirely a >>>> software issue whereas DT is a means to describe the hardware. >>>> >>> Correct; this is exactly the type of information which does _not_ belong int >>> devicetree. >>> >>>> It seems to me that the earlier proposal of communicating to the bridge >>>> whether or not a device should be exposed as hwmon device is the right >>>> thing to do here. >>> >>> Agreed.. >> >> Sorry, what's the "bridge" mean, > > The code which creates a virtual hwmon input when a new thermal zone is > registered (this code is in thermal_core.c.) > >> does it mean we need to add a flag in >> the thermal_zone_device_register() to indicate if we want to register >> virtual hwmon device or not? > > I think so, yes. > > Alternatively the flag could be added to struct > thermal_zone_device_ops, so that you don't have to update all the > callers. But I admit it's a hack as the flag doesn't really belong > there, so I suppose we don't really want to do that. I think it's better to add it to struct thermal_zone_params, the thermal_zone_device_ops is for the callback functions. And I ask it with thermal fw engineers in http://thread.gmane.org/gmane.linux.power-management.general/35874. May be you can look it. > > I have been thinking of an automatic approach, based on comparing the > type string passed to thermal_zone_device_register() with already > registered hwmon devices, but I couldn't come up with something good > and robust enough, so let's forget about it. > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/