Re: [linux-next:master 2519/4500] ucsi.c:undefined reference to `fwnode_usb_role_switch_get'

[Randy Dunlap <rdunlap@infradead.org>]

[adding linux-usb list]

On 1/18/21 12:40 PM, Jack Pham wrote:
> On Mon, Jan 18, 2021 at 06:52:23PM +0800, kernel test robot wrote:
>> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
>> head:   93bf8b946e5f9a0b0c68155597b53fd8ccce2827
>> commit: 89795852c9c46b9b0701f7376d30a1c5ab4d146c [2519/4500] usb: typec: ucsi: Add support for USB role switch
>> config: nios2-randconfig-m031-20210118 (attached as .config)
>> compiler: nios2-linux-gcc (GCC) 9.3.0
>> reproduce (this is a W=1 build):
>>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>>         chmod +x ~/bin/make.cross
>>         # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=89795852c9c46b9b0701f7376d30a1c5ab4d146c
>>         git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>>         git fetch --no-tags linux-next master
>>         git checkout 89795852c9c46b9b0701f7376d30a1c5ab4d146c
>>         # save the attached .config to linux build tree
>>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=nios2 
>>
>> If you fix the issue, kindly add following tag as appropriate
>> Reported-by: kernel test robot <lkp@intel.com>
>>
>> All errors (new ones prefixed by >>):
>>
>>    nios2-linux-ld: drivers/usb/typec/ucsi/ucsi.o: in function `ucsi_register_port':
>>>> ucsi.c:(.text+0x15a8): undefined reference to `fwnode_usb_role_switch_get'
>>    ucsi.c:(.text+0x15a8): relocation truncated to fit: R_NIOS2_CALL26 against `fwnode_usb_role_switch_get'
>>>> nios2-linux-ld: ucsi.c:(.text+0x15e8): undefined reference to `usb_role_switch_set_role'
>>    ucsi.c:(.text+0x15e8): relocation truncated to fit: R_NIOS2_CALL26 against `usb_role_switch_set_role'
>>    nios2-linux-ld: drivers/usb/typec/ucsi/ucsi.o: in function `ucsi_handle_connector_change':
>>>> ucsi.c:(.text+0x1b50): undefined reference to `usb_role_switch_set_role'
>>    ucsi.c:(.text+0x1b50): relocation truncated to fit: R_NIOS2_CALL26 against `usb_role_switch_set_role'
>>    nios2-linux-ld: ucsi.c:(.text+0x1c28): undefined reference to `usb_role_switch_set_role'
>>    ucsi.c:(.text+0x1c28): relocation truncated to fit: R_NIOS2_CALL26 against `usb_role_switch_set_role'
>>
>> Kconfig warnings: (for reference only)
>>    WARNING: unmet direct dependencies detected for SERIAL_CORE_CONSOLE
>>    Depends on TTY && HAS_IOMEM
>>    Selected by
>>    - EARLY_PRINTK
>>
>> ---
>> 0-DAY CI Kernel Test Service, Intel Corporation
>> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
> 
> I have no clue about the nios2, so not sure if this is an arch-specific
> linker error or not.
> 
> Hmm but the .config has the following:
> 
> CONFIG_TYPEC_UCSI=y
> CONFIG_USB_ROLE_SWITCH=m
> 
> So I'm guessing this patch also requires a Kconfig change to disallow
> the above combination? If so, should UCSI have a "depends" or a "select"
> on USB_ROLE_SWITCH?

Hm, there is certainly a mixture of depends and selects in the kernel source
tree. I would say "depends", based on Documentation/kbuild/kconfig-language.rst:
("->" added for emphasis)

  Note:
	select should be used with care. select will force
	a symbol to a value without visiting the dependencies.
	By abusing select you are able to select a symbol FOO even
	if FOO depends on BAR that is not set.
->	In general use select only for non-visible symbols
->	(no prompts anywhere) and for symbols with no dependencies.
	That will limit the usefulness but on the other hand avoid
	the illegal configurations all over.


-- 
~Randy
You can't do anything without having to do something else first.
-- Belefant's Law