Hi, I put this link here, it's a good aditionnal doc for alsa: http://processors.wiki.ti.com/index.php/AM335x_Audio_Driver's_Guide
I was looking the uda code today and I wonder if the driver doesn't need some love also, I'm not totally sure that the I2c reg cache is correctly synchronised with the chip register. It may come from my alsa/pulseaudio setup but I need to tweak the volume some times and retry several times to play a file before I get correctly some sound. It looks like the chip isn't correctly configured after boot. Alexis. On Monday, August 31, 2015 at 8:31:44 AM UTC+2, Andrea Venturi wrote: > > > > Il giorno domenica 30 agosto 2015 13:55:14 UTC+2, Alexis Jeandet ha > scritto: >> >> Hi Andrea, >> >> Indeed my song is mono, so that may explain the issue. >> >> > ok > > >> I also continued to investigate the code from Marcus, which if I >> understood correctly, is based on your code. I got some successful results >> also with this code. I think that Marcus wanted to merge the two structures >> sunxi_priv >> and sunxi_i2s_info and remove the sunxi_iis instance. >> > > > yes; the sunxi_iis is a leftover of the original legacy AW driver and the > useful fields should be folded into the "private" data structure of the > relevant alsa module. > I did this, and seems to work, sent this modifications to Marcus. > > >> There is still some points I don't get yet, if I understand correctly the >> UDA is supposed to generate the sysclock with it's own PLL from bclk? >> > > IIRC it's a PLL from the "left right" clock (ie frame rate 44.1 or 48 KHz) > and the proper UDA register is set when there's WSPLL=1 on device tree.. > Yes I saw that, thanks for the clarification. > > >> Then you have to set the multiplication factor on the UDA? For each song? >> > > for earch sample rate.. > > >> Or you just set it to 256 or 128fs and then just focus on i2s interface? >> In this case 24 bits resolution wouldn't be possible? >> > > the bit clock is a multiple of the FS changing when you have different bit > resolutions. > > >> Don't understand yet what ALSA does exactly, and I didn't check what is >> done on i2c side. >> >> Best regards, >> Alexis. >> > -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
