ASoC: Intel: KMB: Rework disable channel function

All channels are enabled at boot up, this patch ensures that all
channels are disabled at boot and whenever the function is called.
Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
Reviewed-by: Sia Jee Heng <jee.heng.sia@intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200730055319.1522-3-michael.wei.hong.sit@intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/keembay/kmb_platform.c

@@ -109,14 +109,14 @@ static unsigned int kmb_pcm_rx_fn(struct kmb_i2s_info *kmb_i2s,
 static inline void kmb_i2s_disable_channels(struct kmb_i2s_info *kmb_i2s,
 					    u32 stream)
 {
-	struct i2s_clk_config_data *config = &kmb_i2s->config;
 	u32 i;
 
+	/* Disable all channels regardless of configuration*/
 	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		for (i = 0; i < config->chan_nr / 2; i++)
+		for (i = 0; i < MAX_ISR; i++)
 			writel(0, kmb_i2s->i2s_base + TER(i));
 	} else {
-		for (i = 0; i < config->chan_nr / 2; i++)
+		for (i = 0; i < MAX_ISR; i++)
 			writel(0, kmb_i2s->i2s_base + RER(i));
 	}
 }
@@ -637,6 +637,10 @@ static int kmb_plat_dai_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* To ensure none of the channels are enabled at boot up */
+	kmb_i2s_disable_channels(kmb_i2s, SNDRV_PCM_STREAM_PLAYBACK);
+	kmb_i2s_disable_channels(kmb_i2s, SNDRV_PCM_STREAM_CAPTURE);
+
 	dev_set_drvdata(dev, kmb_i2s);
 
 	return ret;

sound/soc/intel/keembay/kmb_platform.h

@@ -90,6 +90,7 @@
 
 #define MAX_CHANNEL_NUM		8
 #define MIN_CHANNEL_NUM		2
+#define MAX_ISR			4
 
 #define TWO_CHANNEL_SUPPORT	2	/* up to 2.0 */
 #define FOUR_CHANNEL_SUPPORT	4	/* up to 3.1 */