Re: [PATCH] staging: comedi: ni_labpc: fix VIRT_TO_BUS dependency

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Mon, May 13, 2013 at 12:02:15PM +0100, Ian Abbott wrote:
> The "ni_labpc" module acts as a low-level comedi driver for various
> Nattional Instruments Lab-PC ISA cards if `CONFIG_NI_LABPC_ISA` is
> enabled, and also as a common module depended on by the "ni_labpc_cs"
> and "ni_labpc_pci" modules.  For ISA cards, it optionally supports the
> use of an ISA DMA channel if `CONFIG_ISA_DMA_API` is enabled, using
> conditionally compiled code.  This conditionally compiled code also
> relies on `virt_to_bus()`, which only exists if `CONFIG_VIRT_TO_BUS` is
> enabled.  Therefore, support for ISA DMA should only be compiled in if
> both `CONFIG_ISA_DMA_API` and `CONFIG_VIRT_TO_BUS` are defined,
> otherwise the "ni_labpc" module fails to compile on kernels that enable
> `CONFIG_ISA_DMA_API` but not `CONFIG_VIRT_TO_BUS`.
> 
> Conditionally define a new macro `NI_LABPC_ISA_DMA` iff both
> `CONFIG_ISA_DMA_API` and `CONFIG_VIRT_TO_BUS` are defined, and change
> the conditional compilation tests to use the new macro instead of
> `CONFIG_ISA_DMA_API`.
> 
> Also, in the "Kconfig", remove the `VIRT_TO_BUS` dependency from the
> `COMEDI_NI_LABPC_ISA` option since the dependency is now checked at
> compile time.
> 
> Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
> ---
>  drivers/staging/comedi/Kconfig            |  1 -
>  drivers/staging/comedi/drivers/ni_labpc.c | 18 +++++++++++-------
>  2 files changed, 11 insertions(+), 8 deletions(-)

Ick, no, I'll take Hartley's patch he sent a week or so ago that fixes
this properly for all architectures.

thanks,

greg k-h