Re: [PATCH 1/6] staging: kpc2000: make kconfig symbol 'KPC2000' select dependencies

[Geordan Neukum]

On Wed, May 22, 2019 at 12:27 PM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> depends on is better than select.  There's a change to depend on UIO for
> this code already in my -linus branch which will show up in Linus's tree
> in a week or so.

Noted on both accounts. Thanks for the feedback and sorry for the
inconvenience on the latter.

> Are you sure we need MFD_CORE as well for this code?

I noticed the build issue when working locally. I was doing
something along the lines of: 'make distclean && make x86_64_defconfig',
selecting 'CONFIG_KPC2000' and 'CONFIG_UIO' via menuconfig, then
running a good old 'make'. From make, I received an error along the
lines of:

ERROR: "mfd_remove_devices"
[drivers/staging/kpc2000/kpc2000/kpc2000.ko] undefined!
ERROR: "mfd_add_devices" [drivers/staging/kpc2000/kpc2000/kpc2000.ko] undefined!
make[1]: *** [scripts/Makefile.modpost:91: __modpost] Error 1
make: *** [Makefile:1290: modules] Error 2

which appears to indicate that those two symbols are undefined. When
I looked, it appeared that those symbols were exported from the
mfd-core which is why I also threw in a select for that Kconfig
symbol. Assuming that I didn't do something silly above, I'd be happy
to submit a new patch (with only a depends on for MFD_CORE) as I
continue trying to fix up the i2c driver.

>Why hasn't that been seen on any build errors?

To be honest, I can't say that I'm familiar with all of the different
build bots out there so I can't even begin to speculate on that one.
If someone could point me in the right direction there, I'd be happy
to investigate further.

Thanks again for your feedback all,
Geordan Neukum