_______________________________________ From: Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> Sent: Tuesday, September 23, 2014 6:37 PM To: Lu Jingchang-B35083 Cc: vinod.koul@xxxxxxxxx; dmaengine@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Subject: Re: [PATCH] dmaengine: fsl-edma: fixup reg offset and hw S/G support in big-endian model On Tue, Sep 23, 2014 at 05:15:19PM +0800, Jingchang Lu wrote: > static u16 edma_readw(struct fsl_edma_engine *edma, void __iomem *addr) > { > - if (edma->big_endian) > - return ioread16be(addr); > - else > + u32 dst; This should be unsigned long, if it needs to exist. > + /* swap the reg offset for these in big-endian mode */ > + if (edma->big_endian) { > + dst = ((u32)addr & ~0x3) | (((u32)addr & 0x3) ^ 0x2); This can be simplified to: addr = (void __iomem *)((unsigned long)addr ^ 2); Ditto for all the other cases. I will do that, Thanks. Best Regards, Jingchang -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html