On 5 December 2016 at 09:12, Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> wrote: > Em Sun, 4 Dec 2016 15:25:25 -0300 > Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx> escreveu: > >> On 4 December 2016 at 10:01, Marcel Hasler <mahasler@xxxxxxxxx> wrote: >> > Hello >> > >> > 2016-12-03 21:46 GMT+01:00 Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx>: >> >> On 2 December 2016 at 08:05, Mauro Carvalho Chehab >> >> <mchehab@xxxxxxxxxxxxxxxx> wrote: >> >>> Em Sun, 27 Nov 2016 12:11:48 +0100 >> >>> Marcel Hasler <mahasler@xxxxxxxxx> escreveu: >> >>> >> >>>> Allow setting a custom record gain for the internal AC97 codec (if available). This can be >> >>>> a value between 0 and 15, 8 is the default and should be suitable for most users. The Windows >> >>>> driver also sets this to 8 without any possibility for changing it. >> >>> >> >>> The problem of removing the mixer is that you need this kind of >> >>> crap to setup the volumes on a non-standard way. >> >>> >> >> >> >> Right, that's a good point. >> >> >> >>> NACK. >> >>> >> >>> Instead, keep the alsa mixer. The way other drivers do (for example, >> >>> em28xx) is that they configure the mixer when an input is selected, >> >>> increasing the volume of the active audio channel to 100% and muting >> >>> the other audio channels. Yet, as the alsa mixer is exported, users >> >>> can change the mixer settings in runtime using some alsa (or pa) >> >>> mixer application. >> >>> >> >> >> >> Yeah, the AC97 mixer we are currently leveraging >> >> exposes many controls that have no meaning in this device, >> >> so removing that still looks like an improvement. >> >> >> >> I guess the proper way is creating our own mixer >> >> (not using snd_ac97_mixer) exposing only the record >> >> gain knob. >> >> >> >> Marcel, what do you think? >> >> -- >> >> Ezequiel García, VanguardiaSur >> >> www.vanguardiasur.com.ar >> > >> > As I have written before, the recording gain isn't actually meant to >> > be changed by the user. In the official Windows driver this value is >> > hard-coded to 8 and cannot be changed in any way. And there really is >> > no good reason why anyone should need to mess with it in the first >> > place. The default value will give the best results in pretty much all >> > cases and produces approximately the same volume as the internal 8-bit >> > ADC whose gain cannot be changed at all, not even by a driver. >> > >> > I had considered writing a mixer but chose not to. If the gain setting >> > is openly exposed to mixer applications, how do you tell the users >> > that the value set by the driver already is the optimal and >> > recommended value and that they shouldn't mess with the controls >> > unless they really have to? By having a module parameter, this setting >> > is practically hidden from the normal user but still is available to >> > power-users if they think they really need it. In the end it's really >> > just a compromise between hiding it completely and exposing it openly. >> > Also, this way the driver guarantees reproducible results, since >> > there's no need to remember the positions of any volume sliders. >> > >> >> Hm, right. I've never changed the record gain, and it's true that it >> doens't really improve the volume. So, I would be OK with having >> a module parameter. >> >> On the other side, we are exposing it currently, through the "Capture" >> mixer control: >> >> Simple mixer control 'Capture',0 >> Capabilities: cvolume cswitch cswitch-joined >> Capture channels: Front Left - Front Right >> Limits: Capture 0 - 15 >> Front Left: Capture 10 [67%] [15.00dB] [on] >> Front Right: Capture 8 [53%] [12.00dB] [on] >> >> So, it would be user-friendly to keep the user interface and continue >> to expose the same knob - even if the default is the optimal, etc. >> >> To be completely honest, I don't think any user is really relying >> on any REC_GAIN / Capture setting, and I'm completely OK >> with having a mixer control or a module parameter. It doesn't matter. > > If you're positive that *all* stk1160 use the ac97 mixer the > same way, and that there's no sense on having a mixer for it, > then it would be ok to remove it. > Let's remove it then! > In such case, then why you need a modprobe parameter to allow > setting the record level? If this mixer entry is not used, > just set it to zero and be happy with that. > Let's remove the module param too, then. Thanks, -- Ezequiel García, VanguardiaSur www.vanguardiasur.com.ar -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
