On Mon, 2013-11-18 at 16:51 +0200, Luiz Augusto von Dentz wrote: > Hi Tanu, > > On Mon, Nov 18, 2013 at 9:25 AM, Tanu Kaskinen > <tanu.kaskinen at linux.intel.com> wrote: > > On Sun, 2013-11-17 at 17:53 +0200, Luiz Augusto von Dentz wrote: > >> Hi Colin, Tanu, > >> > >> On Sun, Nov 17, 2013 at 3:17 PM, Colin Guthrie <gmane at colin.guthr.ie> wrote: > >> > 'Twas brillig, and Tanu Kaskinen at 16/11/13 08:51 did gyre and gimble: > >> >> On Fri, 2013-11-15 at 09:31 +0100, Colin Guthrie wrote: > >> >> I haven't concentrated on the patches enough to even know what > >> >> problem you're solving - is it just that the assertion makes you > >> >> nervous, or is there some other benefit. > >> > > >> > I'm not solving any specific problem per-se. I'm just looking at several > >> > bugs where incorrect profiles appear to be selected by default on first > >> > boot where HDMI is picked over regular analog output (for those alsa > >> > cards which share a single card for both HDMI and Analog output rather > >> > than having it presented as separate cards) despite HDMI having a lower > >> > priority. This lead me to look at this code and got me thinking - this > >> > is the only reason for the patch. > >> > > >> > A further complication to my current bugs is that sometimes Headphone > >> > *ports* are picked by default on first boot even when they are > >> > unavailable and again are not the highest priority port. It seems like > >> > the same problem but in a different, but similar, part of the code. This > >> > is why the second set of patches applied the same logical fixes to the > >> > Sink/Source code that Luiz added to the Card profiles. I think it makes > >> > sense to keep these bits of code approximately in sync regardless of the > >> > outcome of this discussion - the same logic should apply. > >> > >> I can try and apply the same logic to Sink/Source, it just that > >> overall this kind of policy should be in one place or then remove it > >> altogether and make sure the list is always ordered by their module so > >> the core should just pick the first one, the problem we were trying to > >> solve was that there is no hook for priority changes thus they are > >> considered static which is probably why we are relying on > >> pa_card_set_profile_available + > >> PA_CORE_HOOK_CARD_PROFILE_AVAILABLE_CHANGED to indicate the profiles > >> changes. > >> > >> So perhaps we should came to an agreement where and how we should be > >> doing this sort of policy, we could perhaps generalize > >> module-bluetooth-policy, or do we want to continue with per technology > >> policy? > > > > I don't think the policy in module-bluetooth-policy is useful outside > > Bluetooth. module-bluetooth-policy is mainly concerned with the > > transport state in its policy, and the profile availability is only used > > as a proxy for the transport state. I'd be happy if > > module-bluetooth-policy would be changed so that instead of using the > > profile states, it would directly track the transport states using the > > APIs that pa_bluez_discovery provides. But since using the profile > > states as a proxy works fine too, I'm not really asking anyone to do > > anything about that. > > > > From the proposed changes, I think Colin's patches 1 and 3 make sense. > > Preferring PA_AVAILABLE_YES over PA_AVAILABLE_UNKNOWN in generic code > > isn't a good idea. > > Im having a hard time to understand why any policy would prefer a > profile that is less likely to work than another, If you have a "bad" (not very well suited for the use case) profile and a "good" (very well suited for the use case) profile, and the probability of the "bad" profile working is 100% and the probability of the "good" profile working is 99%, do you really see no reason to choose the "good" profile? > but perhaps we are > not willing the mess with other parts of the code that were using this > information in a different way. But then why we are bothering > selecting any profile on pa_card_new? This is a policy decision and it > seems we are not able to do a generic one so it should not even try, > pick the first and be done with it. Yes, it's a policy decision. I would prefer pa_card_new() to always choose the "off" profile by default, but that would require work in policy modules to keep old use cases working. For example, on the first boot of a PC something else than "off" should be selected for the sound card, and currently we don't have any policy module that would ensure that. > Anyway if pa_card_new do not select 'off' by default it pretty much > breaks Bluetooth qualification and if I change the priority of 'off' > profile to force it to be selected it breaks module-bluetooth-policy. Can you tell the Bluetooth qualification requirement that is failing? If it's something HFGW specific, you should be able to implement the desired policy in module-bluetooth-policy, without modifying pa_card_new(). -- Tanu
