Hi Pavel, On Sun, Jan 31, 2016 at 06:36:05PM +0100, Pavel Machek wrote: > On Sun 2016-01-31 02:19:45, Sebastian Reichel wrote: > > Currently userspace knows about the rapuyama version by > > checking, which gpios have been exported. This does no > > longer work with kernel based power management, so export > > a sysfs file, which provides the rapuyama generation. Also > > Umm. So patches 1-2 make it impossible for existing userspace to > detect modem version? > > Even if we re-add the capability with this patch, that makes it bad > idea, no? Thanks for having a look at the patches :) Looks like my commit messages are not verbose enough to show the whole thing. Let me try a more verbose explanation: The N900 and the N950 have more or less the same modem, but with different GPIOs. That basically means, that the powerup/down sequence works differently. OFono has code for supporting power management of both modems by detecting, that some gpios have not been exported. (So if, for some reason, you have not exported some of the GPIOs it will also think, that you have an N950 modem) For kernel based PM there won't be any GPIOs exported, so OFono cannot derive modem generation information from them. OTOH it no longer needs to, since the kernel will take care of the difference between the power up/down sequence. OFono only uses the derived modem generation information for the different power sequence. Unfortunately there is another difference between the N900 and N950 modem, that is not yet covered by OFono at all: The N950 has a broken CBS interface. So the current OFono code base is broken for the N950, even though it can power it up. The broken N950 CBS interface is currently not handled by either ofono, fso-gsmd or sscd. Thus using an explicit new interface is not a problem IMHO. Anyways, after this patchset you have the following methods for using the modem: 1. The existing way using pm=1, which is still the default for now. 2. The existing way using pm=1 + rapuyama_version to check if all GPIOs are there. 3. The new way using pm=2. You can use rapuyama_version for avoiding the CBS interface on N950. I don't think we can easily remove pm=1 support, since it will be needed by existing userspace software. I do think though, that we can change the default from pm=1 to pm=2 when support for the new interface has been integrated into userspace software for some time (e.g. 1 year after it has been merged). -- Sebastian
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