On Sun, Apr 19, 2015 at 11:28 AM, Hans Verkuil <hverkuil@xxxxxxxxx> wrote: > Check the types of llmio and bbmio: > > u32 __iomem *lmmio; > u8 __iomem *bmmio; > > So the values of the pointers are the same, but the types are not. > > So 'lmmio + 1' == 'bmmio + sizeof(u32)' == 'bbmio + 4'. > > Since all the registers are defined as byte offsets relative to the start > of the memory map you cannot just do 'lmmio + reg' since that would be a > factor 4 off. Instead you have to divide by 4 to get it back in line. > > Frankly, I don't think lmmio is necessary at all since readl/writel don't > need a u32 pointer at all since they use void pointers. I never noticed > that when I cleaned up the tw68 driver. Using 'void __iomem *mmio' instead > of lmmio/bmmio and dropping the shifts in the tw_ macros would work just > as well. > > Hope this helps, Oh, indeed, I have forgot this basic thing of pointer arithmetics. Thanks a lot for elaboration and the proposed solution. -- Bluecherry developer. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
