On Sunday 16 March 2008, Jean Delvare wrote: > Hi Rui, > > I am testing your new thermal driver and I am not very happy with the > dependencies introduced by this driver. The ACPI thermal driver selects > the generic thermal driver, which in turn selects the hwmon base > module. As the generic thermal driver's configuration option is a > boolean, this means that as soon as one selects the ACPI thermal driver > (built-in or modular), the hwmon thermal driver has to be built into > the kernel. This is a problem especially when both the ACPI_THERMAL and > THERMAL options default to y. > > I fail to see why we are using select at all. The ACPI thermal driver > clearly works without the generic thermal driver (even though the > generic interface is preferred now.) Likewise, the generic thermal > interface driver doesn't need the hwmon base module to work; the hwmon > interface is only an extension, so it should be possible to build the > generic thermal driver without hwmon support. On top of that, I really > would like to be able to build the generic thermal driver as a module. > > One of the reasons why I would like this to change is this bug: > https://bugzilla.redhat.com/show_bug.cgi?id=437637 > http://bugzilla.kernel.org/show_bug.cgi?id=10259 > (At the moment I think both reports are the exact same bug.) > > We will have to fix this bug of course (not sure how...) but the fact > that the users can't temporarily remove the generic thermal driver is a > problem both for bug investigation and for working around the bug until > it's fixed. I really would like to be able to tell the user "rmmod this > module until we come up with a fix", but right now I can't. > > A more modular setup would give us much more flexibility both at build > time and when bugs are reported. Please think about it. > You are absolutely right -- this is gone from 2.6.25, lets get it right in 2.6.26. BTW. speaking of 2.6.26.... the patch below might become helpful. For it would be nice if at build-time we could just have hwmon_device_register() fail, rather than put a bunch of #ifdef HWMON in our code. thanks, -Len Signed-off-by: Len Brown <len.brown at intel.com> diff --git a/include/linux/hwmon.h b/include/linux/hwmon.h index 6b6ee70..68968cc 100644 --- a/include/linux/hwmon.h +++ b/include/linux/hwmon.h @@ -16,9 +16,13 @@ #include <linux/device.h> +#ifdef CONFIG_HWMON struct device *hwmon_device_register(struct device *dev); - void hwmon_device_unregister(struct device *dev); +#else +static struct device *hwmon_device_register(struct device *dev) { return ERR_PTR(-ENODEV); }; +static void hwmon_device_unregister(struct device *dev) { return; }; +#endif /* Scale user input to sensible values */ static inline int SENSORS_LIMIT(long value, long low, long high)
