hal: Fix EDID information

- Get EDID audio block info from a mixer control instead of a file.
- Fix a bug where the current sad is not updated in the for loop.

Bug: 9430906
Change-Id: I750e307ce1064eeb98d09ea8534a375252630841

hal/audio_hw.c

@@ -356,7 +356,7 @@ static void check_and_route_capture_usecases(struct audio_device *adev,
 static int read_hdmi_channel_masks(struct stream_out *out)
 {
     int ret = 0;
-    int channels = platform_edid_get_max_channels();
+    int channels = platform_edid_get_max_channels(out->dev->platform);
 
     switch (channels) {
         /*
@@ -1318,6 +1318,7 @@ static int adev_open_output_stream(struct audio_hw_device *dev,
     out->channel_mask = AUDIO_CHANNEL_OUT_STEREO;
     out->flags = flags;
     out->devices = devices;
+    out->dev = adev;
 
     /* Init use case and pcm_config */
     if (out->flags & AUDIO_OUTPUT_FLAG_DIRECT &&
@@ -1390,7 +1391,6 @@ static int adev_open_output_stream(struct audio_hw_device *dev,
     out->stream.get_render_position = out_get_render_position;
     out->stream.get_next_write_timestamp = out_get_next_write_timestamp;
 
-    out->dev = adev;
     out->standby = 1;
     /* out->muted = false; by calloc() */
 

hal/msm8960/platform.c

@@ -835,7 +835,7 @@ int platform_set_hdmi_channels(void *platform,  int channel_count)
     return 0;
 }
 
-int platform_edid_get_max_channels(void)
+int platform_edid_get_max_channels(void *platform)
 {
     FILE *file;
     struct audio_block_header header;

hal/msm8974/platform.c

@@ -26,18 +26,14 @@
 #include <platform_api.h>
 #include "platform.h"
 
+#define MIXER_XML_PATH "/system/etc/mixer_paths.xml"
 #define LIB_ACDB_LOADER "libacdbloader.so"
+#define AUDIO_DATA_BLOCK_MIXER_CTL "HDMI EDID"
 
 #define DUALMIC_CONFIG_NONE 0      /* Target does not contain 2 mics */
 #define DUALMIC_CONFIG_ENDFIRE 1
 #define DUALMIC_CONFIG_BROADSIDE 2
 
-/*
- * This is the sysfs path for the HDMI audio data block
- */
-#define AUDIO_DATA_BLOCK_PATH "/sys/class/graphics/fb1/audio_data_block"
-#define MIXER_XML_PATH "/system/etc/mixer_paths.xml"
-
 /*
  * This file will have a maximum of 38 bytes:
  *
@@ -776,40 +772,49 @@ int platform_set_hdmi_channels(void *platform,  int channel_count)
     return 0;
 }
 
-int platform_edid_get_max_channels(void)
+int platform_edid_get_max_channels(void *platform)
 {
-    FILE *file;
-    struct audio_block_header header;
+    struct platform_data *my_data = (struct platform_data *)platform;
+    struct audio_device *adev = my_data->adev;
     char block[MAX_SAD_BLOCKS * SAD_BLOCK_SIZE];
     char *sad = block;
     int num_audio_blocks;
     int channel_count;
     int max_channels = 0;
-    int i;
+    int i, ret, count;
 
-    file = fopen(AUDIO_DATA_BLOCK_PATH, "rb");
-    if (file == NULL) {
-        ALOGE("Unable to open '%s'", AUDIO_DATA_BLOCK_PATH);
+    struct mixer_ctl *ctl;
+
+    ctl = mixer_get_ctl_by_name(adev->mixer, AUDIO_DATA_BLOCK_MIXER_CTL);
+    if (!ctl) {
+        ALOGE("%s: Could not get ctl for mixer cmd - %s",
+              __func__, AUDIO_DATA_BLOCK_MIXER_CTL);
         return 0;
     }
 
-    /* Read audio block header */
-    fread(&header, 1, sizeof(header), file);
+    mixer_ctl_update(ctl);
+
+    count = mixer_ctl_get_num_values(ctl);
 
     /* Read SAD blocks, clamping the maximum size for safety */
-    if (header.length > (int)sizeof(block))
-        header.length = (int)sizeof(block);
-    fread(&block, header.length, 1, file);
+    if (count > (int)sizeof(block))
+        count = (int)sizeof(block);
 
-    fclose(file);
+    ret = mixer_ctl_get_array(ctl, block, count);
+    if (ret != 0) {
+        ALOGE("%s: mixer_ctl_get_array() failed to get EDID info", __func__);
+        return 0;
+    }
 
     /* Calculate the number of SAD blocks */
-    num_audio_blocks = header.length / SAD_BLOCK_SIZE;
+    num_audio_blocks = count / SAD_BLOCK_SIZE;
 
     for (i = 0; i < num_audio_blocks; i++) {
         /* Only consider LPCM blocks */
-        if ((sad[0] >> 3) != EDID_FORMAT_LPCM)
+        if ((sad[0] >> 3) != EDID_FORMAT_LPCM) {
+            sad += 3;
             continue;
+        }
 
         channel_count = (sad[0] & 0x7) + 1;
         if (channel_count > max_channels)

hal/platform_api.h

@@ -34,6 +34,6 @@ int platform_set_mic_mute(void *platform, bool state);
 snd_device_t platform_get_output_snd_device(void *platform, audio_devices_t devices);
 snd_device_t platform_get_input_snd_device(void *platform, audio_devices_t out_device);
 int platform_set_hdmi_channels(void *platform, int channel_count);
-int platform_edid_get_max_channels(void);
+int platform_edid_get_max_channels(void *platform);
 
 #endif // QCOM_AUDIO_PLATFORM_API_H