Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki On 2017-10-12 11:40, Matthijs van Duin wrote: > On Thu, Oct 12, 2017 at 09:07:55AM +0300, Peter Ujfalusi wrote: >> I don't see much benefit of using McASP on OMAP4, only drawbacks... It >> lacks AFIFO so it is prone to underrun and if it underruns you need to >> reset McASP. Been there with the Samsung Galaxy Nexus. > > AESS/ATC isn't able to consistently respond to a DMA request within 20 > us ? Strange.. I would have expected it to have no trouble with that. > (And presumably so did TI, or they would have included AFIFO?) > >> I wonder how Motorola is using the McASP as the OMAP4 version >> (officially) does not support I2S. > > Hmm? I checked the omap4430 TRM and I don't see that mentioned. It seems > to have pins for i2s transmit: > > abe_mcasp_axr O Audio transmit data > abe_mcasp_aclkx O Transmit bit clock > abe_mcasp_ahclkx O Transmit high-frequency master clock > abe_mcasp_afsx O Transmit frame synchronization > abe_mcasp_amute O Mute out to external > abe_mcasp_amutein I Mute in from external > > If it supported s/pdif tx only, then all of these except axr would be > useless. The McASP transmit section uses the S/PDIF industry format, which is supported by the DIT transfer mode of the module. And look for Transfer Modes chapter of McSSP in the OMAP4 TRM. It is DIT only. > > Matthijs > - Péter -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
