On Sat, 13 Feb 2016 22:51:47 +0100, Jean Delvare wrote: > Hi Wolfram, > > On Fri, 12 Feb 2016 20:27:20 +0100, Wolfram Sang wrote: > > On Fri, Jan 29, 2016 at 10:44:52AM +0100, Jean Delvare wrote: > > > The SB800 register reference guide says that the SMBus port selection > > > bits may not always be in register Smbus0En (0x2c) but could > > > alternatively be found in register Smbus0Sel (0x2e) depending on the > > > settings in register Smbus0SelEn (0x2f.) Add support for this > > > configuration. > > > > Were you able to test both cases? > > I don't have the hardware myself so I was not able to test any case. > I was hoping Christian would test. This is the reason why I am logging > which register is used, so that we know if the alternative setting is > ever used. I found the potential problem by looking at the datasheet, > it's not something that has been reported (yet.) > > Meanwhile I have found a datasheet for device 780Bh (named Bolton FCH > on AMD's web site, but Hudson2 in our driver) which suggest that the > "alternative" setting is the only possible one on this chipset. The > register used to figure out the setting is marked as reserved. If the > register exists still and the relevant bit is set, then my patch should > work. If not then a better patch will be needed. > > I'll try to gain access to a system with a Bolton FCH and experiment > with it. I have access to a Bolton FCH system for one week. I tested the port selection and as the datasheet suggested, the "alternative" register is always used on this chipset. Register Smbus0SelEn (0x2f) doesn't exist so the code I submitted doesn't work for this chipset. After unconditionally using 0x2e for port selection, the driver seems to work fine, except that sensors-detect just hung the machine when probing SMBus port 2 address 0x2f (and it's 1200 km away from me and I can't reboot it, yay.) That could be a driver issue or (more likely) just another case of I2C/SMBus device that hates being probed and hangs the system for reprisal. > Then there's the most recent device, codenamed "CZ", for which I have > no information at all. Still looking into that as well, trying to get my hands on both the documentation and the hardware. I would bet that it works the same as the Hudson2/Bolton, but if I can verify that it would be safer. -- Jean Delvare SUSE L3 Support -- 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
