ASoC: S3C platform: Fix s3c2410_dma_started() called at improper time
s3c24xx dma has the auto reload feature, when the the trnasfer is done,
CURR_TC(DSTAT[19:0], current value of transfer count) reaches 0, and DMA
ACK becomes 1, and then, TC(DCON[19:0]) will be loaded into CURR_TC. So
the transmission is repeated.
IRQ is issued while auto reload occurs. We change the DISRC and
DCON[19:0] in the ISR, but at this time, the auto reload has been
performed already. The first block is being re-transmitted by the DMA.
So we need rewrite the DISRC and DCON[19:0] for the next block
immediatly after the this block has been started to be transported.
The function s3c2410_dma_started() is for this perpose, which is called
in the form of "s3c2410_dma_ctrl(prtd->params->channel,
S3C2410_DMAOP_STARTED);" in s3c24xx_pcm_trigger().
But it is not correct. DMA transmission won't start until DMA REQ signal
arrived, it is the time s3c24xx_snd_txctrl(1) or s3c24xx_snd_rxctrl(1)
is called in s3c24xx_i2s_trigger().
In the current framework, s3c24xx_pcm_trigger() is always called before
s3c24xx_pcm_trigger(). So the s3c2410_dma_started() should be called in
s3c24xx_pcm_trigger() after s3c24xx_snd_txctrl(1) or
s3c24xx_snd_rxctrl(1) is called in this function.
However, s3c2410_dma_started() is dma related, to call this function we
should provide the channel number, which is given by
substream->runtime->private_data->params->channel. The private_data
points to a struct s3c24xx_runtime_data object, which is define in
s3c24xx_pcm.c, so s3c2410_dma_started() can't be called in s3c24xx_i2s.c
Fix this by moving the call to signal the DMA started to the DAI
drivers.
Signed-off-by: Shine Liu <liuxian@redflag-linux.com>
Signed-off-by: Shine Liu <shinel@foxmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/s3c24xx/s3c2443-ac97.c b/sound/soc/s3c24xx/s3c2443-ac97.c
index bf16f20..fc1beb0 100644
--- a/sound/soc/s3c24xx/s3c2443-ac97.c
+++ b/sound/soc/s3c24xx/s3c2443-ac97.c
@@ -290,6 +290,9 @@
struct snd_soc_dai *dai)
{
u32 ac_glbctrl;
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ int channel = ((struct s3c24xx_pcm_dma_params *)
+ rtd->dai->cpu_dai->dma_data)->channel;
ac_glbctrl = readl(s3c24xx_ac97.regs + S3C_AC97_GLBCTRL);
switch (cmd) {
@@ -312,6 +315,8 @@
}
writel(ac_glbctrl, s3c24xx_ac97.regs + S3C_AC97_GLBCTRL);
+ s3c2410_dma_ctrl(channel, S3C2410_DMAOP_STARTED);
+
return 0;
}
@@ -334,6 +339,9 @@
int cmd, struct snd_soc_dai *dai)
{
u32 ac_glbctrl;
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ int channel = ((struct s3c24xx_pcm_dma_params *)
+ rtd->dai->cpu_dai->dma_data)->channel;
ac_glbctrl = readl(s3c24xx_ac97.regs + S3C_AC97_GLBCTRL);
switch (cmd) {
@@ -349,6 +357,8 @@
}
writel(ac_glbctrl, s3c24xx_ac97.regs + S3C_AC97_GLBCTRL);
+ s3c2410_dma_ctrl(channel, S3C2410_DMAOP_STARTED);
+
return 0;
}