> -----Original Message----- > From: Eduardo Valentin [mailto:eduardo.valentin@xxxxxx] > Sent: Tuesday, January 07, 2014 8:24 PM > To: Jean Delvare > Cc: Guenter Roeck; Randy Dunlap; Stephen Rothwell; linux- > next@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Frodo Looijaard; > lm-sensors@xxxxxxxxxxxxxx; Zhang, Rui; Eduardo Valentin; linux- > pm@xxxxxxxxxxxxxxx > Subject: Re: [PATCH] hwmon/sensors: fix SENSORS_LM75 dependencies > Importance: High > > On 07-01-2014 08:04, Jean Delvare wrote: > > Hi Guenter, Randy, > > > > On Mon, 06 Jan 2014 18:26:34 -0800, Guenter Roeck wrote: > >> On 01/06/2014 05:09 PM, Randy Dunlap wrote: > >>> From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> > >>> > >>> Fix SENSORS_LM75 dependencies to eliminate build errors: > >>> > >>> drivers/built-in.o: In function `lm75_remove': > >>> lm75.c:(.text+0x12bd8c): undefined reference to > `thermal_zone_of_sensor_unregister' > >>> drivers/built-in.o: In function `lm75_probe': > >>> lm75.c:(.text+0x12c123): undefined reference to > `thermal_zone_of_sensor_register' > >>> > >>> Add depends on THERMAL_OF since that is what provides the > >>> register/unregister functions above. > >>> > >>> Add depends on THERMAL since THERMAL is a tristate (while > THERMAL_OF > >>> is a bool) and SENSORS_LM75 (tristate) needs to be limited to > >>> modular builds when THERMAL=m. > >>> > >>> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> > >>> --- > >>> drivers/hwmon/Kconfig | 2 ++ > >>> 1 file changed, 2 insertions(+) > >>> > >>> --- linux-next-20140106.orig/drivers/hwmon/Kconfig > >>> +++ linux-next-20140106/drivers/hwmon/Kconfig > >>> @@ -650,6 +650,8 @@ config SENSORS_LM73 > >>> config SENSORS_LM75 > >>> tristate "National Semiconductor LM75 and compatibles" > >>> depends on I2C > >>> + depends on THERMAL > >>> + depends on THERMAL_OF > >>> help > >>> If you say yes here you get support for one common type > of > >>> temperature sensor chip, with models including: > >>> > >>> > >> NACK. The driver does not and must not depend on THERMAL. > > > > Correct. > > > >> This needs to be addressed > >> in the thermal code, for example with dummy declarations if > THERMAL=m > >> but SENSORS_LM75=y. The functions are already declared as dummies if > THERMAL_OF=n. > > > > This won't fly I'm afraid, the number of hwmon drivers affected will > > grow in the future and you certainly don't want to have to change the > > generic thermal code every time a new driver is added/converted. > > Agreed > > > > > I've looked at the problem this morning and I will admit I do not > even > > understand what the problem is. In Randy's config, > CONFIG_THERMAL_OF=y > > so both thermal_zone_of_sensor_unregister and > > thermal_zone_of_sensor_register are built-in. SENSORS_LM75=y so the > > calls to these functions are built-in too. I just can't see how this > > can be a problem at link time. Can anyone enlighten me? > > > > > I believe the problem is more in the fact that THERMAL_OF is a bool, > but the way it is in thermal Kconfig, it will link to the thermal > module, in case CONFIG_THERMAL=m. Thus I am proposing the following, > which limits the user to have THERMAL_OF only as builtin and whenever > is selected, it will select THERMAL too. That is: > > > From b643aa260ed4f3514d1ca51b1ecbe4be7652a8d0 Mon Sep 17 00:00:00 2001 > From: Eduardo Valentin <eduardo.valentin@xxxxxx> > Date: Tue, 7 Jan 2014 08:04:02 -0400 > Subject: [PATCH 1/1] thermal: fix compilation issue on > CONFIG_THERMAL_OF dependencies > > Users of API provided by THERMAL_OF config may suffer when > CONFIG_THERMAL=y, causing linking issues, such as: > > drivers/built-in.o: In function `lm75_remove': > lm75.c:(.text+0x12bd8c): undefined reference to > `thermal_zone_of_sensor_unregister' > drivers/built-in.o: In function `lm75_probe': > lm75.c:(.text+0x12c123): undefined reference to > `thermal_zone_of_sensor_register' > > Therefore, this patch limits the compilation build to always have > THERMAL=y, whenever THERMAL_OF=y. In this way, whenever the API user is > built, if THERMAL_OF=y, the build shall have the full thermal support, > otherwise, the thermal API will provide stubs. > > Cc: Zhang Rui <rui.zhang@xxxxxxxxx> > Cc: linux-pm@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxx> > --- > drivers/thermal/Kconfig | 29 ++++++++++++++++------------- > 1 file changed, 16 insertions(+), 13 deletions(-) > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index > 58f98bd..dc315e9 100644 > --- a/drivers/thermal/Kconfig > +++ b/drivers/thermal/Kconfig > @@ -29,19 +29,6 @@ config THERMAL_HWMON > Say 'Y' here if you want all thermal sensors to > have hwmon sysfs interface too. > > -config THERMAL_OF > - bool > - prompt "APIs to parse thermal data out of device tree" > - depends on OF > - default y > - help > - This options provides helpers to add the support to > - read and parse thermal data definitions out of the > - device tree blob. > - > - Say 'Y' here if you need to build thermal infrastructure > - based on device tree. > - > choice > prompt "Default Thermal governor" > default THERMAL_DEFAULT_GOV_STEP_WISE > @@ -235,3 +222,19 @@ source "drivers/thermal/samsung/Kconfig" > endmenu > > endif > + > +menuconfig THERMAL_OF > + bool > + prompt "APIs to parse thermal data out of device tree" > + depends on OF > + select THERMAL > + default y > + help > + This options enables DT thermal API which adds support to > + read and parse thermal data definitions out of the > + device tree blob. This option is mostly used by embedded > + thermal drivers. > + > + Say 'Y' here if you need to build thermal infrastructure > + based on device tree. > + > -- > 1.8.2.1.342.gfa7285d > > Randy, can you please confirm if this fix the issue for you? > The patch looks good to me, will apply it after it has been verified to fix the problem. BTW, I've been thinking of make CONFIG_THERMAL a bool since long time ago, the only thing that blocks me is that Thermal subsystem needs to register a hwmon device for each thermal zone and CONFIG_HWMON is a tristate. Thanks, rui > -- > You have got to be excited about what you are doing. (L. Lamport) > > Eduardo Valentin _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
