Re: [PATCH v2 06/21] fpga: Remove depends on HAS_DMA in case of platform dependency

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Alan Tull <atull@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>,
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Subject: Re: [PATCH v2 06/21] fpga: Remove depends on HAS_DMA in case of platform dependency
Date: Tue, 20 Mar 2018 11:04:09 +0100	[thread overview]
Message-ID: <CAMuHMdU-0VOs6MYrCaCrtRfBqGgaQfox1AgbExNNcYxVC6Uh-Q@mail.gmail.com> (raw)
In-Reply-To: <CANk1AXR3sv2=G-KsQh1p0rdcvy-3XZs6qVy5EMbcAMS6OSVzeQ@mail.gmail.com>

Hi Alan,

On Mon, Mar 19, 2018 at 5:06 PM, Alan Tull <atull@kernel.org> wrote:
> On Fri, Mar 16, 2018 at 8:51 AM, Geert Uytterhoeven
> <geert@linux-m68k.org> wrote:
> This essentially removes this commit
>
> commit 1c8cb409491403036919dd1c6b45013dc8835a44
> Author: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
> Date:   Wed Aug 3 13:45:46 2016 -0700
>
>     drivers/fpga/Kconfig: fix build failure
>
>     While building m32r allmodconfig the build is failing with the error:
>
>       ERROR: "bad_dma_ops" [drivers/fpga/zynq-fpga.ko] undefined!
>
>     Xilinx Zynq FPGA is using DMA but there was no dependency while
>     building.
>
>     Link: http://lkml.kernel.org/r/1464346526-13913-1-git-send-email-sudipm.mukherjee@gmail.com
>     Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
>     Acked-by: Moritz Fischer <moritz.fischer@ettus.com>
>     Cc: Alan Tull <atull@opensource.altera.com>
>     Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
>     Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Yes it does. The major change is that the first (core) series introduces
all needed dummies to do successful compile-testing on NO_DMA=y platforms.

>> Remove dependencies on HAS_DMA where a Kconfig symbol depends on another
>> symbol that implies HAS_DMA, and, optionally, on "|| COMPILE_TEST".
>> In most cases this other symbol is an architecture or platform specific
>> symbol, or PCI.
>>
>> Generic symbols and drivers without platform dependencies keep their
>> dependencies on HAS_DMA, to prevent compiling subsystems or drivers that
>> cannot work anyway.
>>
>> This simplifies the dependencies, and allows to improve compile-testing.
>>
>> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
>> Reviewed-by: Mark Brown <broonie@kernel.org>
>> Acked-by: Robin Murphy <robin.murphy@arm.com>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds