On Sun, May 24, 2009 at 04:10:52PM -0400, Jon Smirl wrote: > On Sun, May 24, 2009 at 2:55 PM, Wolfram Sang <w.s...@pengutronix.de> wrote: > >> Rewrite the mpc5200 audio DMA code to support both I2S and AC97. Make it > >> more robust. > > > > Why is it more robust? > > I've implemented retries for when the AC97 hardware doesn't reset on > first try. About 10% of the time both the Efika and pcm030 AC97 codecs > don't reset on first try and need to be poked multiple times. Failure > is indicated by not having the link clock start ticking. Every once in > a while even five pokes won't get the link started and I have to power > cycle. > > I don't have an oscilloscope, after I get these basic drivers in maybe > someone can put a scope on this and figure out why reset is failing. > I've read the various datasheets and I believe my reset pulses have > the correct timings.
That's good to know. In fact, I think a summary of this should go into the patch description. -- Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ |
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