Re: [PATCH v2 1/3] iio: configfs: Add configfs support to IIO

[Paul Bolle <pebolle@tiscali.nl>]

On Fri, 2015-04-03 at 18:57 +0300, Daniel Baluta wrote:
> --- a/drivers/iio/Kconfig
> +++ b/drivers/iio/Kconfig
> +config IIO_CONFIGFS
> +	tristate "Enable IIO configuration via configfs"
> +	select CONFIGFS_FS
> +	help
> +	  This allows configuring various IIO bits through configfs
> +	  (e.g. software triggers). For more info see
> +	  Documentation/iio/iio_configfs.txt.

> --- a/drivers/iio/Makefile
> +++ b/drivers/iio/Makefile
> @@ -5,6 +5,7 @@
>  obj-$(CONFIG_IIO) += industrialio.o
>  industrialio-y := industrialio-core.o industrialio-event.o inkern.o
>  industrialio-$(CONFIG_IIO_BUFFER) += industrialio-buffer.o
> +industrialio-$(CONFIG_IIO_CONFIGFS) += industrialio-configfs.o
>  industrialio-$(CONFIG_IIO_TRIGGER) += industrialio-trigger.o
>  industrialio-$(CONFIG_IIO_BUFFER_CB) += buffer_cb.o

It seems I didn't pay attention to this Makefile the first time I looked
at this series. And actually reading it I noticed that
industrialio-configfs.o can only be part of the industrial.ko module,
can't it? So this Makefile doesn't allow to build a separate
industrialio-configfs.ko module, right? If so, my previous review, in
which I claimed to spot a nit, was a waste of our time.

Because I now experienced that if this gets build with CONFIG_IIO=m and
CONFIG_IIO_CONFIGFS=y one gets: 
    $ make -C ../.. CONFIG_IIO_CONFIGFS=y M=$PWD industrialio.ko
    make: Entering directory `[...]'
      CC [M]  [...]/drivers/iio/industrialio-core.o
      CC [M]  [...]/linux/drivers/iio/industrialio-event.o
      CC [M]  [...]drivers/iio/inkern.o
      CC [M]  [...]/drivers/iio/industrialio-buffer.o
      CC [M]  [...]/drivers/iio/industrialio-configfs.o
      CC [M]  [...]/drivers/iio/industrialio-trigger.o
      CC [M]  [...]/drivers/iio/buffer_cb.o
      LD [M]  [...]/drivers/iio/industrialio.o
    [...]/drivers/iio/industrialio-configfs.o: In function `iio_configfs_init':
    industrialio-configfs.c:(.init.text+0x0): multiple definition of `init_module'
    [...]/drivers/iio/industrialio-core.o:industrialio-core.c:(.init.text+0x0): first defined here
    [...]/drivers/iio/industrialio-configfs.o: In function `iio_configfs_exit':
    industrialio-configfs.c:(.exit.text+0x0): multiple definition of `cleanup_module'
    [...]/drivers/iio/industrialio-core.o:industrialio-core.c:(.exit.text+0x0): first defined here
    make[1]: *** [[...]/drivers/iio/industrialio.o] Error 1
    make: *** [industrialio.ko] Error 2
    make: Leaving directory `[...]'

(I didn't yet test other configurations.)

So before I waste even more of your time: were you trying to make
configfs support a part of the industrialio module or were you trying to
make configfs support available as a separate module?

Thanks,


Paul Bolle