diff mbox

[v3,2/5] ASoC: dwc: Iterate over all channels

Message ID 67cea1f0a74c333ec2048c7796cda37302d45e95.1418826016.git.Andrew.Jackson@arm.com (mailing list archive)
State Accepted
Commit db2c1f9e38a38e0f9294b5a8a83d744f68fbe726
Headers show

Commit Message

Andrew Jackson Dec. 19, 2014, 4:18 p.m. UTC 
From: Andrew Jackson <Andrew.Jackson@arm.com>

The Designware core can be configured with up to four stereo channels.
Each stereo channel is individually configured so, when the driver's
hw_params call is made, each requested stereo channel has to be
programmed.

Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com>
---
 sound/soc/dwc/designware_i2s.c |   35 ++++++++++++++++-------------------
 1 files changed, 16 insertions(+), 19 deletions(-)

Comments

Mark Brown Dec. 22, 2014, 1:53 p.m. UTC | #1 
On Fri, Dec 19, 2014 at 04:18:06PM +0000, Andrew Jackson wrote:

> The Designware core can be configured with up to four stereo channels.
> Each stereo channel is individually configured so, when the driver's
> hw_params call is made, each requested stereo channel has to be
> programmed.

This is quite unclear to someone who doesn't know the hardware, is this
a bug fix or a new feature?  It looks like it's a fix...
Andrew Jackson Dec. 22, 2014, 2:08 p.m. UTC | #2 
On 12/22/14 13:53, Mark Brown wrote:
> On Fri, Dec 19, 2014 at 04:18:06PM +0000, Andrew Jackson wrote:
> 
>> The Designware core can be configured with up to four stereo channels.
>> Each stereo channel is individually configured so, when the driver's
>> hw_params call is made, each requested stereo channel has to be
>> programmed.
> 
> This is quite unclear to someone who doesn't know the hardware, is this
> a bug fix or a new feature?  It looks like it's a fix...
> 

It is a fix.  In the Designware core, each stereo channel is configured
individually.  So, when hw_params is called to configure N channels, 
N/2 stereo channels need to be configured in the core.  The existing
code doesn't do this and will only configure the highest numbered 
channel.

    Andrew
Mark Brown Dec. 22, 2014, 3:06 p.m. UTC | #3 
On Fri, Dec 19, 2014 at 04:18:06PM +0000, Andrew Jackson wrote:
> From: Andrew Jackson <Andrew.Jackson@arm.com>
> 
> The Designware core can be configured with up to four stereo channels.
> Each stereo channel is individually configured so, when the driver's
> hw_params call is made, each requested stereo channel has to be
> programmed.

Applied, thanks.
diff mbox

Patch

diff --git a/sound/soc/dwc/designware_i2s.c b/sound/soc/dwc/designware_i2s.c
index 5c13303..2ba1e2e 100644
--- a/sound/soc/dwc/designware_i2s.c
+++ b/sound/soc/dwc/designware_i2s.c
@@ -209,16 +209,9 @@  static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
 
 	switch (config->chan_nr) {
 	case EIGHT_CHANNEL_SUPPORT:
-		ch_reg = 3;
-		break;
 	case SIX_CHANNEL_SUPPORT:
-		ch_reg = 2;
-		break;
 	case FOUR_CHANNEL_SUPPORT:
-		ch_reg = 1;
-		break;
 	case TWO_CHANNEL_SUPPORT:
-		ch_reg = 0;
 		break;
 	default:
 		dev_err(dev->dev, "channel not supported\n");
@@ -227,18 +220,22 @@  static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
 
 	i2s_disable_channels(dev, substream->stream);
 
-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-		i2s_write_reg(dev->i2s_base, TCR(ch_reg), xfer_resolution);
-		i2s_write_reg(dev->i2s_base, TFCR(ch_reg), 0x02);
-		irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
-		i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x30);
-		i2s_write_reg(dev->i2s_base, TER(ch_reg), 1);
-	} else {
-		i2s_write_reg(dev->i2s_base, RCR(ch_reg), xfer_resolution);
-		i2s_write_reg(dev->i2s_base, RFCR(ch_reg), 0x07);
-		irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
-		i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x03);
-		i2s_write_reg(dev->i2s_base, RER(ch_reg), 1);
+	for (ch_reg = 0; ch_reg < (config->chan_nr / 2); ch_reg++) {
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+			i2s_write_reg(dev->i2s_base, TCR(ch_reg),
+				      xfer_resolution);
+			i2s_write_reg(dev->i2s_base, TFCR(ch_reg), 0x02);
+			irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
+			i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x30);
+			i2s_write_reg(dev->i2s_base, TER(ch_reg), 1);
+		} else {
+			i2s_write_reg(dev->i2s_base, RCR(ch_reg),
+				      xfer_resolution);
+			i2s_write_reg(dev->i2s_base, RFCR(ch_reg), 0x07);
+			irq = i2s_read_reg(dev->i2s_base, IMR(ch_reg));
+			i2s_write_reg(dev->i2s_base, IMR(ch_reg), irq & ~0x03);
+			i2s_write_reg(dev->i2s_base, RER(ch_reg), 1);
+		}
 	}
 
 	i2s_write_reg(dev->i2s_base, CCR, ccr);