audio: fix I2S noise at start-up

PD#168452: audio: fix I2S noise at start-up

Change-Id: I0c255509419773f57c09fcd814e72db2e5ad7beb
Signed-off-by: Shuai Li <shuai.li@amlogic.com>

diff --git a/sound/soc/amlogic/meson/meson.c b/sound/soc/amlogic/meson/meson.c
index af81e4e..296b0dd 100644 (file)
--- a/sound/soc/amlogic/meson/meson.c
+++ b/sound/soc/amlogic/meson/meson.c
@@ -28,6 +28,7 @@
 #include <linux/platform_device.h>
 #include <linux/i2c.h>
 #include <linux/delay.h>
+#include <linux/dma-mapping.h>
 
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -55,10 +56,13 @@
 
 #define DRV_NAME "aml_meson_snd_card"
 
-static int i2sbuf[DEFAULT_PLAYBACK_SIZE];
-static void aml_i2s_play(void)
+#define I2S_PLAY_BUF_SIZE 512
+#define I2S_PLAY_BUF_EXT_SIZE 64
+
+static void aml_i2s_play(struct aml_audio_private_data *p_aml_audio)
 {
-       int size = DEFAULT_PLAYBACK_SIZE;
+       struct snd_soc_card *card = (struct snd_soc_card *)p_aml_audio->data;
+       size_t size = I2S_PLAY_BUF_SIZE+I2S_PLAY_BUF_EXT_SIZE;
 
        audio_util_set_i2s_format(AUDIO_ALGOUT_DAC_FORMAT_DSP);
 #ifdef CONFIG_AMLOGIC_SND_SPLIT_MODE
@@ -66,14 +70,24 @@ static void aml_i2s_play(void)
 #else
        audio_set_i2s_mode(AIU_I2S_MODE_PCM16);
 #endif
-       memset(i2sbuf, 0, sizeof(i2sbuf));
-       audio_set_aiubuf((virt_to_phys(i2sbuf)
-               + (DEFAULT_PLAYBACK_SIZE - 1))
-                       & (~(DEFAULT_PLAYBACK_SIZE - 1)),
-               size, 2, SNDRV_PCM_FORMAT_S16_LE);
+       p_aml_audio->area = dmam_alloc_coherent(card->dev,
+                       size, &p_aml_audio->addr, GFP_KERNEL);
+       memset(p_aml_audio->area, 0, size);
+       audio_set_aiubuf(p_aml_audio->addr, I2S_PLAY_BUF_SIZE,
+               2, SNDRV_PCM_FORMAT_S16_LE);
        audio_out_i2s_enable(1);
+}
 
+static void aml_i2s_stop(struct aml_audio_private_data *p_aml_audio)
+{
+       struct snd_soc_card *card = (struct snd_soc_card *)p_aml_audio->data;
+       size_t size = I2S_PLAY_BUF_SIZE+I2S_PLAY_BUF_EXT_SIZE;
+
+       audio_out_i2s_enable(0);
+       dmam_free_coherent(card->dev, size, p_aml_audio->area,
+                       p_aml_audio->addr);
 }
+
 static void aml_audio_start_timer(struct aml_audio_private_data *p_aml_audio,
                                  unsigned long delay)
 {
@@ -769,12 +783,13 @@ static int aml_audio_probe(struct platform_device *pdev)
                goto err;
        }
 
+       p_aml_audio->data = (void *)card;
+
        ret = of_property_read_bool(np, "i2sclk_disable_startup");
        if (!ret) {
                pr_info("enable i2sclk in startup\n");
-               aml_i2s_play();
+               aml_i2s_play(p_aml_audio);
        }
-       p_aml_audio->data = (void *)card;
        INIT_WORK(&p_aml_audio->pinmux_work, aml_pinmux_work_func);
        schedule_work(&p_aml_audio->pinmux_work);
 
@@ -801,6 +816,8 @@ static void aml_audio_shutdown(struct platform_device *pdev)
        state = pinctrl_lookup_state(p_audio->pin_ctl, "aml_snd_suspend");
        if (!IS_ERR(state))
                pinctrl_select_state(p_audio->pin_ctl, state);
+
+       aml_i2s_stop(p_audio);
 }
 
 static const struct of_device_id amlogic_audio_of_match[] = {

diff --git a/sound/soc/amlogic/meson/meson.h b/sound/soc/amlogic/meson/meson.h
index 3d15328..8acbbf4 100644 (file)
--- a/sound/soc/amlogic/meson/meson.h
+++ b/sound/soc/amlogic/meson/meson.h
@@ -71,6 +71,8 @@ struct aml_audio_private_data {
        struct switch_dev mic_sdev; /* for android */
 #endif
        struct work_struct pinmux_work;
+       unsigned char *area;
+       dma_addr_t addr;
 };
 
 #endif