ENGR00170453 SSI: close ssi_clk when idle

close ssi_clk when ssi is idle.

Signed-off-by: Gary Zhang <b13634@freescale.com>

diff --git a/sound/soc/imx/imx-ssi.c b/sound/soc/imx/imx-ssi.c
index 5f0f6c7217efcd81a8661740ab4203c3228eb6a4..31e6805748691192b02cbc9be0bb838897639b17 100644 (file)
--- a/sound/soc/imx/imx-ssi.c
+++ b/sound/soc/imx/imx-ssi.c
@@ -359,6 +359,31 @@ static int imx_ssi_trigger(struct snd_pcm_substream *substream, int cmd,
        return 0;
 }
 
+static int imx_ssi_startup(struct snd_pcm_substream *substream,
+                          struct snd_soc_dai *cpu_dai)
+{
+       struct imx_ssi *ssi = snd_soc_dai_get_drvdata(cpu_dai);
+
+       if (cpu_dai->playback_active || cpu_dai->capture_active)
+               return 0;
+
+       clk_enable(ssi->clk);
+
+       return 0;
+}
+
+static void imx_ssi_shutdown(struct snd_pcm_substream *substream,
+                            struct snd_soc_dai *cpu_dai)
+{
+       struct imx_ssi *ssi = snd_soc_dai_get_drvdata(cpu_dai);
+
+       /* shutdown SSI if neither Tx or Rx is active */
+       if (cpu_dai->playback_active || cpu_dai->capture_active)
+               return;
+
+       clk_disable(ssi->clk);
+}
+
 static struct snd_soc_dai_ops imx_ssi_pcm_dai_ops = {
        .hw_params      = imx_ssi_hw_params,
        .set_fmt        = imx_ssi_set_dai_fmt,
@@ -366,6 +391,8 @@ static struct snd_soc_dai_ops imx_ssi_pcm_dai_ops = {
        .set_sysclk     = imx_ssi_set_dai_sysclk,
        .set_tdm_slot   = imx_ssi_set_dai_tdm_slot,
        .trigger        = imx_ssi_trigger,
+       .startup        = imx_ssi_startup,
+       .shutdown       = imx_ssi_shutdown,
 };
 
 int snd_imx_pcm_mmap(struct snd_pcm_substream *substream,
@@ -470,8 +497,25 @@ static int imx_ssi_dai_probe(struct snd_soc_dai *dai)
        return 0;
 }
 
+#ifdef CONFIG_PM
+static int imx_ssi_dai_suspend(struct snd_soc_dai *dai)
+{
+       return 0;
+}
+
+static int imx_ssi_dai_resume(struct snd_soc_dai *dai)
+{
+       return 0;
+}
+#else
+#define imx_ssi_suspend        NULL
+#define imx_ssi_resume NULL
+#endif
+
 static struct snd_soc_dai_driver imx_ssi_dai = {
        .probe = imx_ssi_dai_probe,
+       .suspend = imx_ssi_dai_suspend,
+       .resume = imx_ssi_dai_resume,
        .playback = {
                .channels_min = 1,
                .channels_max = 2,