[GIT PULL] qcom SoC changes for 4.4 *RESEND*

[Arnd Bergmann]

On Friday 16 October 2015 13:04:17 Stephen Boyd wrote:
> On 10/16, Arnd Bergmann wrote:
> > On Friday 16 October 2015 09:56:30 Stephen Boyd wrote:
> > > 
> > > Can you share your .config? It looks like there are stubs for these, so
> > > I'm lost how we got undefined references.
> > > 
> > http://pastebin.com/HtrC510p
> > 
> > The problem is CONFIG_HWSPINLOCK=m && CONFIG_QCOM_SMEM=y. Sorry for sending
> > an incomplete patch description, I had not noticed those wrapper functions.
> > 
> > My patch fixes the issue, but does not allow you to build QCOM_SMEM without
> > HWSPINLOCK. If we want that configuration to be valid, we need one of
> > the two changes below:
> > 
> > diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> > index eec76141d9b9..cae0ffa19bca 100644
> > --- a/drivers/soc/qcom/Kconfig
> > +++ b/drivers/soc/qcom/Kconfig
> > @@ -22,7 +22,7 @@ config QCOM_PM
> >  config QCOM_SMEM
> >  	tristate "Qualcomm Shared Memory Manager (SMEM)"
> >  	depends on ARCH_QCOM
> > -	depends on HWSPINLOCK
> > +	depends on HWSPINLOCK && !HWSPINLOCK
> 
> What does this mean?

This is the magic way in Kconfig to express what we want ;-)

It says it depends on either HWSPINLOCK being disabled (!HWSPINLOCK),
or it depends on HWSPINLOCK. The latter implies that QCOM_SMEM cannot
be built-in when HWSPINLOCK=m, but they are allowed to both be built-in.

> Is it missing an =m?

No

> >  	help
> >  	  Say y here to enable support for the Qualcomm Shared Memory Manager.
> >  	  The driver provides an interface to items in a heap shared among all
> > diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h
> > index 859d673d98c8..cdfd9fd2ba11 100644
> > --- a/include/linux/hwspinlock.h
> > +++ b/include/linux/hwspinlock.h
> > @@ -59,7 +59,7 @@ struct hwspinlock_pdata {
> >  	int base_id;
> >  };
> >  
> > -#if defined(CONFIG_HWSPINLOCK) || defined(CONFIG_HWSPINLOCK_MODULE)
> > +#if IS_REACHABLE(CONFIG_HWSPINLOCK)
> >  
> >  int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
> >  		const struct hwspinlock_ops *ops, int base_id, int num_locks);
> > 
> 
> I'd prefer this patch. Is there some way to capture that
> QCOM_SMEM must be a module if HWSPINLOCK is a module unless we're
> doing a compile test, in which case we don't care?

The problem here is that while we avoid the build error, we get the
counterintuitive behavior that you can have the HWSPINLOCK module
loaded but the built-in QCOM_SMEM module does not use it because
it wasn't reachable at compile time.

> I guess that would just be:
> 
> 	depends on HWSPINLOCK || COMPILE_TEST

This would not solve the randconfig build problem.

	Arnd