Re: [linux-stable-rc:queue/5.4 7091/9999] drivers/staging/comedi/drivers/comedi_isadma.c:25:17: error: implicit declaration of function 'claim_dma_lock'

[Greg Ungerer]

On 13/4/22 18:54, Arnd Bergmann wrote:
> On Wed, Apr 13, 2022 at 1:07 AM kernel test robot <lkp@xxxxxxxxx> wrote:
> > Hi Arnd,
> >
> > FYI, the error/warning still remains.
> >
> > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git queue/5.4
> > head:   9185989d84b918f49f720061cedc29c8ed039797
> > commit: 53a72858bcae7eaa7df8d167dbf60682d70f82a6 [7091/9999] m68knommu: only set CONFIG_ISA_DMA_API for ColdFire sub-arch
> > config: m68k-randconfig-r011-20220412 (https://download.01.org/0day-ci/archive/20220413/202204130751.lUeRF1y2-lkp@xxxxxxxxx/config)
>
> I've seen a couple of reports for this now, in a few other drivers.
> The intention of
> my old patch was to limit the use of the set_dma_addr() etc interface
> for coldfire,
> because they are not implemented on the other MMU-less m68k platform
> (dragonball), which caused build failures there.
>
> However, changing the dependency to COLDFIRE means that we now build
> the drivers that need this on /other/ machines that don't have the complete
> API. In particular, coldfire-v4 with MMU is now able to select the COMEDI
> ISA drivers that fail to build because a different part of the API
> (claim_dma_lock())
> is defined in asm/floppy.h on m68k instead of asm/dma.h as it is on the
> other architectures.
>
> I don't actually see any driver on coldfire using the ISA DMA API any more at
> all, so I wonder if we should just drop the symbol entirely, and perhaps remove
> the definitions for coldfire as well. These are the drivers I found
> using the DMA
> API:
>
> $ git grep -wl set_dma_mode\\\|request_dma drivers/ sound/
> drivers/ata/pata_icside.c
> drivers/comedi/drivers/comedi_isadma.c
> drivers/mmc/host/wbsd.c
> drivers/net/appletalk/ltpc.c
> drivers/net/ethernet/3com/3c515.c
> drivers/net/ethernet/amd/lance.c
> drivers/net/ethernet/amd/ni65.c
> drivers/net/ethernet/cirrus/cs89x0.c
> drivers/net/hamradio/dmascc.c
> drivers/net/wan/cosa.c
> drivers/net/wan/hostess_sv11.c
> drivers/net/wan/sealevel.c
> drivers/net/wan/z85230.c
> drivers/parport/parport_pc.c
> drivers/pnp/resource.c
> drivers/scsi/aha1542.c
> drivers/scsi/arm/cumana_2.c
> drivers/scsi/arm/eesox.c
> drivers/scsi/arm/powertec.c
> drivers/scsi/mpt3sas/mpt3sas_base.c
> drivers/scsi/mpt3sas/mpt3sas_base.h
> drivers/scsi/qla1280.c
> drivers/scsi/qla1280.h
> drivers/scsi/qla4xxx/ql4_def.h
> drivers/scsi/qla4xxx/ql4_mbx.c
> drivers/scsi/qla4xxx/ql4_os.c
> drivers/usb/gadget/udc/net2272.c
> drivers/usb/musb/musb_cppi41.c
> drivers/video/fbdev/pvr2fb.c
> sound/core/isadma.c
> sound/isa/es1688/es1688_lib.c
> sound/isa/gus/gus_main.c
> sound/soc/au1x/dma.c
>
> Greg (Ungerer), do you see any of these that are used on Coldfire?
> I can rule out most of them, but there are a few that are unclear to me.

I think the cs89x0 driver may have been used on at least one platform
in the past. But nothing that is currently supported in mainline code.
So we can safely assume none of these are required for ColdFire platforms.

Regards
Greg