ASoC: omap-mcbsp: Support SND_SOC_DAIFMT_CBM_CFS for omap3/4

Add SND_SOC_DAIFMT_CBM_CFS support for omap3/omap4. The patch was tested on
a pandaboard-es board connected to the pcm1792a codec. mcbspx_fsx must
configured as output and mcbspx_clkx must be configured as input.

Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/omap/omap-mcbsp.c

@@ -433,6 +433,11 @@ static int omap_mcbsp_dai_set_dai_fmt(struct snd_soc_dai *cpu_dai,
 		/* Sample rate generator drives the FS */
 		regs->srgr2	|= FSGM;
 		break;
+	case SND_SOC_DAIFMT_CBM_CFS:
+		/* McBSP slave. FS clock as output */
+		regs->srgr2	|= FSGM;
+		regs->pcr0	|= FSXM;
+		break;
 	case SND_SOC_DAIFMT_CBM_CFM:
 		/* McBSP slave */
 		break;