ASoC: omap-mcbsp: Correct clock muxing for CLKR/FSR signals

Remove the no longer valid check for McBSP1 regarding to signal mux
selection (on OMAP4 McBSP4 has 6 pin setup).
Only clear the srgr2, pcr0 register configuration if the requested clock
configuration will actually going to touch it. In this way we can avoid
issues if the CLKR/FSR mux has been configured after the clock selection.

We are going to check for the valid McBSP port in the
omap_mcbsp_6pin_src_mux() function based on the validity of the mux_signal
callback (which is only valid for ports having 6 pin setup).

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@ti.com>

sound/soc/omap/mcbsp.c

@@ -690,7 +690,9 @@ int omap2_mcbsp_set_clks_src(struct omap_mcbsp *mcbsp, u8 fck_src_id)
 int omap_mcbsp_6pin_src_mux(struct omap_mcbsp *mcbsp, u8 mux)
 {
 	const char *signal, *src;
-	int ret = 0;
+
+	if (mcbsp->pdata->mux_signal)
+		return -EINVAL;
 
 	switch (mux) {
 	case CLKR_SRC_CLKR:
@@ -713,10 +715,7 @@ int omap_mcbsp_6pin_src_mux(struct omap_mcbsp *mcbsp, u8 mux)
 		return -EINVAL;
 	}
 
-	if (mcbsp->pdata->mux_signal)
-		ret = mcbsp->pdata->mux_signal(mcbsp->dev, signal, src);
-
-	return ret;
+	return mcbsp->pdata->mux_signal(mcbsp->dev, signal, src);
 }
 
 #define max_thres(m)			(mcbsp->pdata->buffer_size)

sound/soc/omap/omap-mcbsp.c

@@ -511,17 +511,21 @@ static int omap_mcbsp_dai_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
 			return -EBUSY;
 	}
 
-	/* The McBSP signal muxing functions are only available on McBSP1 */
-	if (clk_id == OMAP_MCBSP_CLKR_SRC_CLKR ||
-	    clk_id == OMAP_MCBSP_CLKR_SRC_CLKX ||
-	    clk_id == OMAP_MCBSP_FSR_SRC_FSR ||
-	    clk_id == OMAP_MCBSP_FSR_SRC_FSX)
-		if (cpu_class_is_omap1() || cpu_dai->id != 1)
-			return -EINVAL;
-
-	mcbsp->in_freq = freq;
-	regs->srgr2	&= ~CLKSM;
-	regs->pcr0	&= ~SCLKME;
+	if (clk_id == OMAP_MCBSP_SYSCLK_CLK ||
+	    clk_id == OMAP_MCBSP_SYSCLK_CLKS_FCLK ||
+	    clk_id == OMAP_MCBSP_SYSCLK_CLKS_EXT ||
+	    clk_id == OMAP_MCBSP_SYSCLK_CLKX_EXT ||
+	    clk_id == OMAP_MCBSP_SYSCLK_CLKR_EXT) {
+		mcbsp->in_freq = freq;
+		regs->srgr2	&= ~CLKSM;
+		regs->pcr0	&= ~SCLKME;
+	} else if (cpu_class_is_omap1()) {
+		/*
+		 * McBSP CLKR/FSR signal muxing functions are only available on
+		 * OMAP2 or newer versions
+		 */
+		return -EINVAL;
+	}
 
 	switch (clk_id) {
 	case OMAP_MCBSP_SYSCLK_CLK:
@@ -552,23 +556,15 @@ static int omap_mcbsp_dai_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
 
 
 	case OMAP_MCBSP_CLKR_SRC_CLKR:
-		if (cpu_class_is_omap1())
-			break;
 		err = omap_mcbsp_6pin_src_mux(mcbsp, CLKR_SRC_CLKR);
 		break;
 	case OMAP_MCBSP_CLKR_SRC_CLKX:
-		if (cpu_class_is_omap1())
-			break;
 		err = omap_mcbsp_6pin_src_mux(mcbsp, CLKR_SRC_CLKX);
 		break;
 	case OMAP_MCBSP_FSR_SRC_FSR:
-		if (cpu_class_is_omap1())
-			break;
 		err = omap_mcbsp_6pin_src_mux(mcbsp, FSR_SRC_FSR);
 		break;
 	case OMAP_MCBSP_FSR_SRC_FSX:
-		if (cpu_class_is_omap1())
-			break;
 		err = omap_mcbsp_6pin_src_mux(mcbsp, FSR_SRC_FSX);
 		break;
 	default: