Re: [PATCH 1/1] mmc: host: enable OMAP DMA engine support for omap hosts by default

On Fri, Aug 24, 2012 at 02:10:38PM +0200, Peter Meerwald wrote:

with Linux 3.6-rc3:

CONFIG_DMA_OMAP=m
CONFIG_DMA_ENGINE=y
CONFIG_DMA_VIRTUAL_CHANNELS=m
CONFIG_MMC_OMAP_HS=y
CONFIG_SPI_OMAP24XX=y
CONFIG_MTD_NAND_OMAP2=y

  LD      init/built-in.o
drivers/built-in.o: In function `omap2_mcspi_setup':
/home/pmeerw/linux-pmeerw/drivers/spi/spi-omap2-mcspi.c:859: undefined reference to `omap_dma_filter_fn'
drivers/built-in.o: In function `omap_nand_probe':
/home/pmeerw/linux-pmeerw/drivers/mtd/nand/omap2.c:1371: undefined reference to `omap_dma_filter_fn'
drivers/built-in.o: In function `omap_hsmmc_probe':
/home/pmeerw/linux-pmeerw/drivers/mmc/host/omap_hsmmc.c:2039: undefined reference to `omap_dma_filter_fn'
make: *** [vmlinux] Error 1

in addition to SPI and MMC, there seems to be also a NAND dependency

Yes.  Unlike the PL08x driver, OMAP has no way to pass the filter function
into its drivers, and I didn't want the pain of fiddling around with DT
crap to try and work out how to do this.  So what you have here is
something that I got as far as I could, and TI then wanted it pushed into
mainline.

I have no solution for the above at present - the long term solution is
to sort out how to deal with DMA engine with DT etc.  At the moment,
there has been discussion about this but no solution.