Hi, At Fri, 24 Jan 2003 13:41:29 +0100, Pieter Palmers wrote: > > I took a look at the Intel AC97 2.2 specs. It seems that the behaviour > described here is a AC97 2.2 recommendation. take a look at 1 & 2 of 5.2.1.
thanks! > 5.2.1 AUX_OUT Options > As identified in the previous section, there are three common uses for > AC `97's second output. AC `97 2.2 addresses all three uses by > renaming the second output as AUX_OUT, Register 04h as Aux Out Volume, > and the pins as AUX_OUT_L, AUX_OUT_C, and AUX_OUT_R. > > Driver developers should be aware that the AC `97 AUX_OUT may be > implemented in one of three ways: > > 1.True line level out.Support for a true consumer > equipment-compatible (10 k\Omega ) line level output that does not > change with master volume settings. Either fixed or fixable via the > independent volume controls in Register 04h, the output level provides a > 1V RMS (2.8 V peak-to-peak) output level for a 0 dB gain PCM output > stream. When implemented this way, AUX_OUT is equivalent to AC `97 2.1's > LNLVL_OUT definitions. > > 2.Headphone out. AUX_OUT can be implemented to support integrated > headphone amplifier with 32 \Omega drive capability and independent > volume control via Register 04h. When implemented this way, AUX_OUT is > equivalent to AC `97 1.03 original HP_OUT definitions > > 3. 4-Channel out. In Codecs that support 4-channel operation, > AUX_OUT can be implemented to support the additional (i.e. L&R > Surround) outputs. When implemented this way, AUX_OUT will be referred > to 4CH_OUT. In 4CH_OUT implementations, L and R Surround output is > controlled via Surround Volume Register 38h, not Aux Out Volume 04h, > and powered down via the PRJ (SDAC) bit in Register 2Ah. > > AUX_OUT defaults to be LNLVL_OUT unless HP_OUT or 4CH_OUT support is > detected. hmm, then we need to implement the controls for the register 0x04 even if RESET/ID4 is 0..? currently, we build them only when RESET/ID4 is detected. but i've not known which chip has LNLVL without RESET/ID4. needs to check the spec for each chip. confusingly, there are ac97 chips which sets RESET/ID4 but uses AUX_OUT as LNLVL, such as ALC200, ALC201A or ALC202A. and on these chips, we have the problem as $SUBJECT states. furthremore, ALC201/2 uses it as HP_OUT, even though they have the same id as ALC201/2A! in this case, we need to check PCI subdev ID... Takashi ------------------------------------------------------- This SF.NET email is sponsored by: SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See! http://www.vasoftware.com _______________________________________________ Alsa-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-devel
