commit 058165c3b0cfc1c6c7caff92f1403a76d0bb2cc0
author Ashish Jain <ashishj@codeaurora.org> Wed Sep 28 23:18:48 2016 +0530
committer Gerrit - the friendly Code Review server <code-review@localhost> Wed Oct 19 08:25:26 2016 -0700
tree b30198d6671c32c99d6000094201b4baf323f07e
parent 37850abb13b0758064a4fae8119be0f7cc59d2d6

audio: Update hal to handle 32bit/384kHz playback.

Update the mixer control string used to configure BE at 32bit format
with correct value.
For HDMI backend, as it does not support 32bit/384kHz, configure
BE to 24bit/192kHz if supported by the connected device.
Configure speaker device to bit width supported on the device
if stream bit width is greater than 24 bit.

Change-Id: Ic1c437d4cb15db709941eec065d40b2ae173ea9d

hal/msm8974/platform.c

diff --git a/hal/msm8974/platform.c b/hal/msm8974/platform.c
index a175d40..fa67342 100644
--- a/hal/msm8974/platform.c
+++ b/hal/msm8974/platform.c
@@ -2165,7 +2165,7 @@
 {
     if ((snd_device < SND_DEVICE_MIN) || (snd_device >= SND_DEVICE_MAX)) {
         ALOGE("%s: Invalid snd_device = %d", __func__, snd_device);
-        return DEFAULT_OUTPUT_SAMPLING_RATE;
+        return CODEC_BACKEND_DEFAULT_BIT_WIDTH;
     }
     return backend_bit_width_table[snd_device];
 }
@@ -4363,7 +4363,7 @@
             else
                  ret = mixer_ctl_set_enum_by_string(ctl, "S24_LE");
         } else if (bit_width == 32) {
-            ret = mixer_ctl_set_enum_by_string(ctl, "S24_LE");
+            ret = mixer_ctl_set_enum_by_string(ctl, "S32_LE");
         } else {
             ret = mixer_ctl_set_enum_by_string(ctl, "S16_LE");
         }
@@ -4705,6 +4705,12 @@
         }
     } else if ((usecase->devices & AUDIO_DEVICE_OUT_SPEAKER) ||
                (usecase->devices & AUDIO_DEVICE_OUT_EARPIECE) ) {
+
+        if (bit_width >= 24) {
+            bit_width = platform_get_snd_device_bit_width(SND_DEVICE_OUT_SPEAKER);
+            ALOGD("%s:becf: afe: reset bitwidth to %d (based on supported"
+                   " value for this platform)", __func__, bit_width);
+        }
         sample_rate = CODEC_BACKEND_DEFAULT_SAMPLE_RATE;
         ALOGD("%s:becf: afe: playback on codec device not supporting native playback set "
             "default Sample Rate(48k)", __func__);
@@ -4725,6 +4731,15 @@
         hdmi_backend_cfg.channels = channels;
         hdmi_backend_cfg.passthrough_enabled = false;
 
+        /*
+         * HDMI does not support 384Khz/32bit playback hence configure BE to 24b/192Khz
+         * TODO: Instead have the validation against edid return the next best match
+         */
+        if (bit_width > 24)
+            hdmi_backend_cfg.bit_width = 24;
+        if (sample_rate > 192000)
+            hdmi_backend_cfg.sample_rate = 192000;
+
         platform_check_hdmi_backend_cfg(adev, usecase, backend_idx, &hdmi_backend_cfg);
 
         bit_width = hdmi_backend_cfg.bit_width;

hal/msm8974/platform.h

diff --git a/hal/msm8974/platform.h b/hal/msm8974/platform.h
index 2b65950..c231843 100644
--- a/hal/msm8974/platform.h
+++ b/hal/msm8974/platform.h
@@ -257,7 +257,14 @@
  * We should take care of returning proper size when AudioFlinger queries for
  * the buffer size of an input/output stream
  */
+
+/* for 384Khz output below period size corresponds to 20ms worth duration of buffer,
+ * current implementation can support buffer size of 40ms duration
+ * for 32b/384Khz/stereo output.
+ */
 #define DEEP_BUFFER_OUTPUT_PERIOD_SIZE 1920
+#define DEEP_BUFFER_OUTPUT_PERIOD_DURATION 40 /* 40 milisecs */
+
 #define DEEP_BUFFER_OUTPUT_PERIOD_COUNT 2
 #define LOW_LATENCY_OUTPUT_PERIOD_SIZE 240
 #define LOW_LATENCY_OUTPUT_PERIOD_COUNT 2