Messages in this thread | | | Date | Wed, 17 Jun 2009 10:40:10 +0930 | Subject | Re: is_device_dma_capable | From | Malcom Blaney <> |
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Thanks Fujita, your patch worked a treat!
2009/6/16 FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>: > On Tue, 16 Jun 2009 17:53:03 +0930 > Malcom Blaney <malcolm.blaney@maptek.com.au> wrote: > >> Hi Fujita, >> >> 2009/6/16 FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>: >> > You use X86_32, right? >> >> I have CONFIG_X86_32=y in my config file. >> >> > >> > In 2.6.25, X86_32 and X86_64 had the own dma_alloc_coherent >> > implementations; X86_32 accepted a device having dma_mask that is not >> > initialized however X86_64 didn't, I think. >> > >> > When we merged them, we chose to prohibit a device having dma_mask >> > that is not initialized. I'm not sure the DMA docs say this but IMO >> > it's good to require drivers to set up dma_mask (and >> > coherent_dma_mask) properly if the drivers want DMA. >> > >> >> If you could point me in the direction of how to set these values >> correctly, I would appreciate it. > > You hit the problem that a device that parport_pc_probe_port creates > but doesn't set up the dma_mask properly, right (I'm not familiar with > the driver at all so I might misunderstand something)? > > If so, I guess that the following patch works (only compile tested). > > > diff --git a/drivers/parport/parport_pc.c b/drivers/parport/parport_pc.c > index 151bf5b..1af57b7 100644 > --- a/drivers/parport/parport_pc.c > +++ b/drivers/parport/parport_pc.c > @@ -2271,6 +2271,9 @@ struct parport *parport_pc_probe_port(unsigned long int base, > if (IS_ERR(pdev)) > return NULL; > dev = &pdev->dev; > + > + dev->coherent_dma_mask = DMA_BIT_MASK(24); > + dev->dma_mask = &dev->coherent_dma_mask; > } > > ops = kmalloc(sizeof(struct parport_operations), GFP_KERNEL); > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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