[alsa-devel] recording problem in beagleboard-mcbsp

[Peter Ujfalusi]

On 04/14/2015 12:39 PM, Peter Ujfalusi wrote:
> OK, got another SD card.
> McBSP3 in master mode works (no codec connected) playback and capture as well.
> 
> The pins for McBSP3:
> OMAP3_CORE1_IOPAD(0x2172, PIN_OUTPUT | MUX_MODE0) /* mcbsp3_fsx.mcbsp3_fsx */
> OMAP3_CORE1_IOPAD(0x2178, PIN_OUTPUT | MUX_MODE1) /* uart2_tx.mcbsp3_clkx */
> OMAP3_CORE1_IOPAD(0x2174, PIN_OUTPUT | MUX_MODE1) /* uart2_cts.mcbsp3_dx */
> OMAP3_CORE1_IOPAD(0x2176, PIN_INPUT | MUX_MODE1)  /* uart2_rts.mcbsp3_dr */
> 
> I still not sure why McBSP1 is not working..

This pinctrl setting is not correct for McBSP3. I was changing the registers
on the fly, that's why it was working when I replied.

In McBSP3 master mode, you need:
OMAP3_CORE1_IOPAD(0x2172, PIN_INPUT | MUX_MODE0) /* mcbsp3_fsx.mcbsp3_fsx */
OMAP3_CORE1_IOPAD(0x2178, PIN_INPUT | MUX_MODE1) /* uart2_tx.mcbsp3_clkx */
OMAP3_CORE1_IOPAD(0x2174, PIN_OUTPUT | MUX_MODE1) /* uart2_cts.mcbsp3_dx */
OMAP3_CORE1_IOPAD(0x2176, PIN_INPUT | MUX_MODE1)  /* uart2_rts.mcbsp3_dr */

Which would work in McBSP3 slave mode as well.
Playback, capture works (McBSP3 master). I have connected DX to DR and
captured whatever I was playing. Came back fine.

As for McBSP1 I think this should get it working:
OMAP3_CORE1_IOPAD(0x2196, PIN_INPUT | MUX_MODE0) /* mcbsp1_fsx.mcbsp1_fsx */
OMAP3_CORE1_IOPAD(0x218e, PIN_INPUT | MUX_MODE0) /* mcbsp1_fsr.mcbsp1_fsr */
OMAP3_CORE1_IOPAD(0x2198, PIN_INPUT | MUX_MODE0) /* mcbsp1_clkx.mcbsp1_clkx */
OMAP3_CORE1_IOPAD(0x218c, PIN_INPUT | MUX_MODE0) /* mcbsp1_clkr.mcbsp1_clkr */
OMAP3_CORE1_IOPAD(0x2190, PIN_OUTPUT | MUX_MODE0) /* mcbsp1_dx.mcbsp1_dx */
OMAP3_CORE1_IOPAD(0x2192, PIN_INPUT | MUX_MODE0)  /* mcbsp1_dr.mcbsp1_dr */

If McBSP1 is slave, then connect the FS to both FSX and FSR and do the same
for CLK.

-- 
Péter