On Thu, 2008-08-21 at 15:28 -0700, David Miller wrote: > From: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> > Date: Fri, 22 Aug 2008 08:05:02 +1000 > > > Apple additionally have different ways of representing multiple busses > > on one controller though. On some machines, they just use bits 0xF00 of > > the address as the bus number, which is a bit gross, and on some, they > > have sub-nodes i2c-bus@NN under the controller. > > Ok, Sun uses a 2-cell scheme. We can handle both cases of reg > encoding quite easily: > > 1) If there is a single cell, tread bits 8 and above as bus number. > They will be zero on Sparc. Depends if you want also to handle 10-bit addresses... though the support for that could be enabled by an explicit property 10-bit-addresses in the controller node... But as I said before, I wouldn't worry too much about powermac for now, it's not using this code and may never do. > 2) If there are two cells, first cell is bus number. > > For the hierarchical case, I'm not so sure how to handle it. > > Also, last night, I posted patches to the I2C list to add bus > addressing support to the I2C code and the PCF algo implementation. Ben. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
