On 11/02/2016 02:56 PM, Joel Stanley wrote: > On Wed, Nov 2, 2016 at 11:45 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote: >> On Wednesday 02 November 2016, Cédric Le Goater wrote: >>> The Aspeed SoCs have two BT interfaces : one is IPMI compliant and the >>> other is H8S/2168 compliant. >>> >>> The current ipmi/bt-bmc driver implements the IPMI version and we >>> should reflect its nature in the compatible node name using >>> 'aspeed,ast2400-ibt-bmc' instead of 'aspeed,ast2400-bt-bmc'. The >>> latter should be used for a H8S interface driver if it is implemented >>> one day. >>> >>> Signed-off-by: Cédric Le Goater <clg@xxxxxxxx> >> >> We generally try to avoid changing the compatible strings after the >> fact, but it's probably ok in this case. As the device tree changes are not merged yet, we thought we had some more time to fine tune the naming. >> I don't understand who decides which of the two interfaces is used: >> is it the same register set that can be driven by either one or the >> other driver, or do you expect to have two drivers that can both >> be active in the same system and talk to different hardware once >> you get there? > > It's the second case. The H8S BT has a different register layout so it > would require a different driver. yes. > We don't yet have a driver for the other BT device, but there was > recent talk of using it as an alternate (non-ipmi channel) between the > BMC and the host. Before that discussion I wasn't aware that the H8S > BT existed. I suggested we fix this up before it hits a final release. > > Cédric, do you think ast2400-ibt-bmc or ast2400-ipmi-bt-bmc does a > better job of describing the hardware here? The specs refer to the two interfaces as BT (non IPMI) and iBT (IPMI). I think we can keep the same naming. > While we're modifying the binding, should we add a compat string for > the ast2500? Well, if the change in this patch is fine for all, may be we can add the ast2500 compat string in a followup patch ? Thanks, C. > Cheers, > > Joel > >> >> If the first one of these is true, it seems a little awkward to >> use the DT compatible string to decide which driver to use rather >> than making the decision in the OS. >> >> Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
