On 23/06/11 12:45, Ralf Baechle wrote: > On architectures that don't define PAGE_KERNEL_NOCACHE, the Comedi driver turns > into tragedy: > > CC [M] drivers/staging/comedi/drivers.o > drivers/staging/comedi/drivers.c: In function ‘comedi_buf_alloc’: > drivers/staging/comedi/drivers.c:505:41: error: ‘PAGE_KERNEL_NOCACHE’ undeclared (first use in this function) > drivers/staging/comedi/drivers.c:505:41: note: each undeclared identifier is rep orted only once for each function it appears in > make[3]: *** [drivers/staging/comedi/drivers.o] Error 1 > > Restrict the driver to only those architectures that define PAGE_KERNEL_NOCACHE. > > PAGE_KERNEL_NOCACHE is a kludge - some system architectures such as SGI IP27 > are even uable to offer uncached operation - at least in the way an unwitting > driver might assume. I haven't looked in details how the driver is using > the area vmaped with PAGE_KERNEL_NOCACHE but maybe doing it XFS-style using > cached memory and the flush_kernel_vmap_range / invalidate_kernel_vmap_range > APIs in conjunction with the DMA API is a practical alternative. > > Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx> > > drivers/staging/comedi/Kconfig | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig > index 1502d80..bccdc12 100644 > --- a/drivers/staging/comedi/Kconfig > +++ b/drivers/staging/comedi/Kconfig > @@ -2,6 +2,7 @@ config COMEDI > tristate "Data acquisition support (comedi)" > default N > depends on m > + depends on BROKEN || FRV || M32R || MN10300 || SUPERH || TILE || X86 I'm sure I got comedi to compile on a 32-bit PPC board not that long ago. Has something changed, or is this just not an exhaustive list? > ---help--- > Enable support a wide range of data acquisition devices > for Linux. > _______________________________________________ > devel mailing list > devel@xxxxxxxxxxxxxxxxxxxxxx > http://driverdev.linuxdriverproject.org/mailman/listinfo/devel -- Martyn Welch (Principal Software Engineer) | Registered in England and GE Intelligent Platforms | Wales (3828642) at 100 T +44(0)127322748 | Barbirolli Square, Manchester, E martyn.welch@xxxxxx | M2 3AB VAT:GB 927559189 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
