On Mon, Jun 12, 2017 at 1:19 PM, Peter Rosin <peda@xxxxxxxxxx> wrote: > On 2017-06-12 11:38, Andy Shevchenko wrote: >> On Mon, Jun 12, 2017 at 12:28 PM, Peter Rosin <peda@xxxxxxxxxx> wrote: >>> On 2017-06-12 11:11, Andy Shevchenko wrote: >>>> On Mon, Jun 12, 2017 at 6:42 AM, Song liwei <liwei.song@xxxxxxxxxxxxx> wrote: >>>>> From: Liwei Song <liwei.song@xxxxxxxxxxxxx> >> >>>>> After finished I2C block read/write, when unmap the data buffer, >>>>> a wrong device address was pass to dma_unmap_single(), >> >>>>> the right >>>>> device address should be "dev" not "&adap->dev", the relation is >>>>> *(&adap->dev) == dev. >>>> >>>> This is confusing. You are telling that there are two copies of struct >>>> device here? >>> >>> Yes, there are two copies. >> >> No, there is not. See below. > > What I meant was that there are the struct device in pci_dev->dev and the > struct device in adap->dev. That seems like two copies of struct device > to me. They are not copies. That's my point. > I didn't mean that they are copies in the sense that they have the > same content, but in the sense that they are both struct device. > > I guess we can argue ourselves blue over this point. See above. >> There are two struct devices, > > Hmm, two struct devices, I seem to recall that from somewhere... :-) Okay, it's possible bad wording from my side. >> one is a real PCI device, which >> represents actual device what *does* DMA. >> This struct should be used according to DMA API. > When you put it like that, it's obvious that the patch is correct. I agreed with this in the first place! See my first reply. > I had > this feeling that little thought had gone into the choice to pick "dev" > over "&adap->dev", that's all. As I said, my concern is the commit message to the change which is totally confusing. -- With Best Regards, Andy Shevchenko -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
