[PATCH 2/3] ASoC: atmel_ssc_dai: refactor the startup and shutdown

From: Bo Shen
Date: Fri Jan 30 2015 - 04:39:07 EST


In startup function, enable ssc clock and in shutdown function,
disable clock. And also remove disable ssc in shutdown function,
as ssc is disabled in prepare function.

Signed-off-by: Bo Shen <voice.shen@xxxxxxxxx>
---

sound/soc/atmel/atmel_ssc_dai.c | 28 +++++++++++-----------------
1 file changed, 11 insertions(+), 17 deletions(-)

diff --git a/sound/soc/atmel/atmel_ssc_dai.c b/sound/soc/atmel/atmel_ssc_dai.c
index c1d93b8..0ed5ac3 100644
--- a/sound/soc/atmel/atmel_ssc_dai.c
+++ b/sound/soc/atmel/atmel_ssc_dai.c
@@ -204,6 +204,13 @@ static int atmel_ssc_startup(struct snd_pcm_substream *substream,
pr_debug("atmel_ssc_startup: SSC_SR=0x%u\n",
ssc_readl(ssc_p->ssc->regs, SR));

+ /* Enable PMC peripheral clock for this SSC */
+ pr_debug("atmel_ssc_dai: Starting clock\n");
+ clk_enable(ssc_p->ssc->clk);
+
+ /* Reset the SSC to keep it at a clean status */
+ ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
+
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
dir = 0;
dir_mask = SSC_DIR_MASK_PLAYBACK;
@@ -250,11 +257,6 @@ static void atmel_ssc_shutdown(struct snd_pcm_substream *substream,
dma_params = ssc_p->dma_params[dir];

if (dma_params != NULL) {
- ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);
- pr_debug("atmel_ssc_shutdown: %s disabled SSC_SR=0x%08x\n",
- (dir ? "receive" : "transmit"),
- ssc_readl(ssc_p->ssc->regs, SR));
-
dma_params->ssc = NULL;
dma_params->substream = NULL;
ssc_p->dma_params[dir] = NULL;
@@ -266,10 +268,6 @@ static void atmel_ssc_shutdown(struct snd_pcm_substream *substream,
ssc_p->dir_mask &= ~dir_mask;
if (!ssc_p->dir_mask) {
if (ssc_p->initialized) {
- /* Shutdown the SSC clock. */
- pr_debug("atmel_ssc_dai: Stopping clock\n");
- clk_disable(ssc_p->ssc->clk);
-
free_irq(ssc_p->ssc->irq, ssc_p);
ssc_p->initialized = 0;
}
@@ -280,6 +278,10 @@ static void atmel_ssc_shutdown(struct snd_pcm_substream *substream,
ssc_p->cmr_div = ssc_p->tcmr_period = ssc_p->rcmr_period = 0;
}
spin_unlock_irq(&ssc_p->lock);
+
+ /* Shutdown the SSC clock. */
+ pr_debug("atmel_ssc_dai: Stopping clock\n");
+ clk_disable(ssc_p->ssc->clk);
}


@@ -597,14 +599,6 @@ static int atmel_ssc_hw_params(struct snd_pcm_substream *substream,
rcmr, rfmr, tcmr, tfmr);

if (!ssc_p->initialized) {
-
- /* Enable PMC peripheral clock for this SSC */
- pr_debug("atmel_ssc_dai: Starting clock\n");
- clk_enable(ssc_p->ssc->clk);
-
- /* Reset the SSC and its PDC registers */
- ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));
-
ssc_writel(ssc_p->ssc->regs, PDC_RPR, 0);
ssc_writel(ssc_p->ssc->regs, PDC_RCR, 0);
ssc_writel(ssc_p->ssc->regs, PDC_RNPR, 0);
--
2.3.0.rc0

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