staging: vc04_services: Re-add dependency on HAS_DMA to BCM2835_VCHIQ

Thanks to stubs for the NO_DMA=y case, drivers that use the DMA API can
be compile-tested on systems that do not support DMA.  Hence the
dependency of BCM2835_VCHIQ on HAS_DMA was dropped to increase compile
coverage.

Unfortunately compilers became smarter, leading to new failures.
E.g. for a CONFIG_SUN3=y allmodconfig kernel with gcc 9.4.0:

    drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c: In function ‘free_pagelist’:
    arch/m68k/include/asm/string.h:72:25: warning: argument 2 null where non-null expected [-Wnonnull]
       72 | #define memcpy(d, s, n) __builtin_memcpy(d, s, n)
	  |                         ^~~~~~~~~~~~~~~~~~~~~~~~~
    drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c:614:4: note: in expansion of macro ‘memcpy’
      614 |    memcpy((char *)kmap(pages[0]) +
	  |    ^~~~~~
    arch/m68k/include/asm/string.h:72:25: note: in a call to built-in function ‘__builtin_memcpy’
       72 | #define memcpy(d, s, n) __builtin_memcpy(d, s, n)
	  |                         ^~~~~~~~~~~~~~~~~~~~~~~~~
    drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c:614:4: note: in expansion of macro ‘memcpy’
      614 |    memcpy((char *)kmap(pages[0]) +
	  |    ^~~~~~

This happens because the compiler can trace back the source pointer to a
allocation by dma_alloc_attrs(), which always returns NULL if NO_DMA=y.

Avoid this reinstating the dependency of the BCM2835_VCHIQ symbol on
HAS_DMA, and by restricting the selection of BCM2835_VCHIQ.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/da55bd87eebf1a969dc8ccd807843319833f6c40.1650888813.git.geert@linux-m68k.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Geert Uytterhoeven 2022-04-25 14:18:25 +02:00 committed by Greg Kroah-Hartman
parent 8896ac5d0d
commit f3e93e3e25
3 changed files with 4 additions and 3 deletions

View File

@ -13,6 +13,7 @@ if BCM_VIDEOCORE
config BCM2835_VCHIQ
tristate "BCM2835 VCHIQ"
depends on HAS_DMA
imply VCHIQ_CDEV
help
Broadcom BCM2835 and similar SoCs have a VPU called VideoCore. This config

View File

@ -3,7 +3,7 @@ config SND_BCM2835
tristate "BCM2835 Audio"
depends on (ARCH_BCM2835 || COMPILE_TEST) && SND
select SND_PCM
select BCM2835_VCHIQ
select BCM2835_VCHIQ if HAS_DMA
help
Say Y or M if you want to support BCM2835 built in audio.
This driver handles both 3.5mm and HDMI audio, by leveraging

View File

@ -3,8 +3,8 @@ config VIDEO_BCM2835
tristate "BCM2835 Camera"
depends on MEDIA_SUPPORT
depends on VIDEO_DEV && (ARCH_BCM2835 || COMPILE_TEST)
select BCM2835_VCHIQ
select BCM2835_VCHIQ_MMAL
select BCM2835_VCHIQ if HAS_DMA
select BCM2835_VCHIQ_MMAL if HAS_DMA
select VIDEOBUF2_VMALLOC
select BTREE
help