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 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. -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
