On Fri, 2006-04-14 at 14:06 +0800, Jaya Kumar wrote: > On 3/26/06, Jim Gettys <[EMAIL PROTECTED]> wrote: > > On Sun, 2006-03-26 at 20:24 +0800, Jaya Kumar wrote: > > > > > > AD1888 support in ALSA seems complete to me. Are you having a specific > > > problem with it? > > > > It works as far as it goes, as far as we know. > > > > However, it could go further ensuring parts of the chips not in use are > > off, and more importantly, entirely powering the chip off when not in > > use, which the 1888 is capable of, and many other chips are not able to > > do. > > I have a couple of questions here. Are you planning to use the 2.6.16 > cs5535audio driver for your first rev boards? The PM support I posted > goes as far as turning off the AC Link. The upper layer of ALSA > suspend has the responsibility for disabling the codec on the other > side. Currently what ALSA does is to shutdown the following: EAPD, HP > Amp, ADC & DAC, Analog Mixer with Vref On. I suppose it could go > further but that would involve testing whether it resumes properly.
On a human power machine, we really care about milliamps. And yes, full off of the chip needs testing, and we gather it is a bit interesting getting it to wake up again. > I > could add a ad1888 specific build_ops->suspend in the codec layer to > shutdown completely. I'd need someone to test this for me since > nothing here seems to use the AD1888. Unless of course you're willing > to ship a test board to India. Well, I will probably be able to do so this summer. We are having a large number (500) boards built for developers to hack on. Though I also may have a couple sample AD1888's that can plug into old Pentium 4 mother boards that have a funky slot that often existed on that era motherboard. I forget the name of this slot. When we have developer boards, we expect to be able to ship worldwide; one of OLPC's sponsors is Brightstar, who have worldwide logistics capability (including India), and has volunteered to help us distribute and support the developer boards. > > > As you might imagine, we care a whole lot about what our minimum power > > consumption is, since the CPU will be able to suspend to RAM while > > Just to be certain, are you using the GX2 or the GX3 cpu on your first > rev boards? Are you using the CS5535 or the CS5536 bridge? GX2. CS5536. > > > keeping the display running (using our DCON chip). So our bottom end > > power consumption when, say, reading a book and not doing anything, > > should be in the neighborhood of .5 watts; even if we continue to > > Impressive goals. Yup. > > > forward packets in the mesh, (which we can also do with the CPU > > suspended, due to the choice of the Marvel wirless chip), we'll be in > > the neighborhood of 1 watt. > > Do you already have drivers for all this stuff? I'd be happy to help > in that area. Nope. A simple matter of programming as they say ;-). I'm sure we could use help. > > > > > So power consumption that would be lost in the noise on most systems > > will be very significant on our system. We'll be in the values normally > > only seen on PDA's. > > Regards, > > - Jim > > > > > > > > > > There are other items on your kernel work list that look attractive to > > > me. Let me know if you actually need help on them or already have > > > people to work on them. > > > > > > Best regards, > > > jayakumar > > > -- > > > olpc-software mailing list > > > [email protected] > > > https://www.redhat.com/mailman/listinfo/olpc-software > > -- > > Jim Gettys > > One Laptop Per Child > > > > > > -- Jim Gettys One Laptop Per Child -- olpc-software mailing list [email protected] https://www.redhat.com/mailman/listinfo/olpc-software
