ALSA: hda - hdmi: Add ELD emulation for ATI/AMD codecs

ATI/AMD HDMI/DP codecs do not include standard HDA ELD (EDID-like data)
support.

In place of providing access to an ELD buffer, various vendor-specific
verbs are provided to provide the relevant information. Revision ID 3
and later (0x100300 as reported by procfs codec#X) have support for
providing more information than the previous revisions (but only if
supported by the display driver).

Generate ELD from the information provided by the vendor-specific verbs
on ATI/AMD codecs.

The specification is available at:
http://www.x.org/docs/AMD/AMD_HDA_verbs_v2.pdf

v2: moved code to hda_eld.c and cleaned it up
v3: adapted to hdmi_ops infrastructure

Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi>
Tested-by: Peter Frühberger <fritsch@xbmc.org> # v2
Tested-by: Olivier Langlois <olivier@trillion01.com> # v2
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 151 insertions, 0 deletions

diff --git a/sound/pci/hda/hda_eld.c b/sound/pci/hda/hda_eld.c
index f62356c2f54c..32d3e3855a6e 100644
--- a/sound/pci/hda/hda_eld.c
+++ b/sound/pci/hda/hda_eld.c
@@ -2,6 +2,7 @@
  * Generic routines and proc interface for ELD(EDID Like Data) information
  *
  * Copyright(c) 2008 Intel Corporation.
+ * Copyright (c) 2013 Anssi Hannula <anssi.hannula@iki.fi>
  *
  * Authors:
  *              Wu Fengguang <wfg@linux.intel.com>
@@ -633,3 +634,153 @@ void snd_hdmi_eld_update_pcm_info(struct parsed_hdmi_eld *e,
         hinfo->maxbps = min(hinfo->maxbps, maxbps);
         hinfo->channels_max = min(hinfo->channels_max, channels_max);
 }
+
+
+/* ATI/AMD specific stuff (ELD emulation) */
+
+#define ATI_VERB_SET_AUDIO_DESCRIPTOR   0x776
+#define ATI_VERB_SET_SINK_INFO_INDEX    0x780
+#define ATI_VERB_GET_SPEAKER_ALLOCATION 0xf70
+#define ATI_VERB_GET_AUDIO_DESCRIPTOR   0xf76
+#define ATI_VERB_GET_AUDIO_VIDEO_DELAY  0xf7b
+#define ATI_VERB_GET_SINK_INFO_INDEX    0xf80
+#define ATI_VERB_GET_SINK_INFO_DATA     0xf81
+
+#define ATI_SPKALLOC_SPKALLOC           0x007f
+#define ATI_SPKALLOC_TYPE_HDMI          0x0100
+#define ATI_SPKALLOC_TYPE_DISPLAYPORT   0x0200
+
+/* first three bytes are just standard SAD */
+#define ATI_AUDIODESC_CHANNELS          0x00000007
+#define ATI_AUDIODESC_RATES             0x0000ff00
+#define ATI_AUDIODESC_LPCM_STEREO_RATES 0xff000000
+
+/* in standard HDMI VSDB format */
+#define ATI_DELAY_VIDEO_LATENCY         0x000000ff
+#define ATI_DELAY_AUDIO_LATENCY         0x0000ff00
+
+enum ati_sink_info_idx {
+        ATI_INFO_IDX_MANUFACTURER_ID    = 0,
+        ATI_INFO_IDX_PRODUCT_ID         = 1,
+        ATI_INFO_IDX_SINK_DESC_LEN      = 2,
+        ATI_INFO_IDX_PORT_ID_LOW        = 3,
+        ATI_INFO_IDX_PORT_ID_HIGH       = 4,
+        ATI_INFO_IDX_SINK_DESC_FIRST    = 5,
+        ATI_INFO_IDX_SINK_DESC_LAST     = 22, /* max len 18 bytes */
+};
+
+int snd_hdmi_get_eld_ati(struct hda_codec *codec, hda_nid_t nid,
+                         unsigned char *buf, int *eld_size, bool rev3_or_later)
+{
+        int spkalloc, ati_sad, aud_synch;
+        int sink_desc_len = 0;
+        int pos, i;
+
+        /* ATI/AMD does not have ELD, emulate it */
+
+        spkalloc = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_SPEAKER_ALLOCATION, 0);
+
+        if (!spkalloc) {
+                snd_printd(KERN_INFO "HDMI ATI/AMD: no speaker allocation for ELD\n");
+                return -EINVAL;
+        }
+
+        memset(buf, 0, ELD_FIXED_BYTES + ELD_MAX_MNL + ELD_MAX_SAD * 3);
+
+        /* version */
+        buf[0] = ELD_VER_CEA_861D << 3;
+
+        /* speaker allocation from EDID */
+        buf[7] = spkalloc & ATI_SPKALLOC_SPKALLOC;
+
+        /* is DisplayPort? */
+        if (spkalloc & ATI_SPKALLOC_TYPE_DISPLAYPORT)
+                buf[5] |= 0x04;
+
+        pos = ELD_FIXED_BYTES;
+
+        if (rev3_or_later) {
+                int sink_info;
+
+                snd_hda_codec_write(codec, nid, 0, ATI_VERB_SET_SINK_INFO_INDEX, ATI_INFO_IDX_PORT_ID_LOW);
+                sink_info = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_SINK_INFO_DATA, 0);
+                put_unaligned_le32(sink_info, buf + 8);
+
+                snd_hda_codec_write(codec, nid, 0, ATI_VERB_SET_SINK_INFO_INDEX, ATI_INFO_IDX_PORT_ID_HIGH);
+                sink_info = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_SINK_INFO_DATA, 0);
+                put_unaligned_le32(sink_info, buf + 12);
+
+                snd_hda_codec_write(codec, nid, 0, ATI_VERB_SET_SINK_INFO_INDEX, ATI_INFO_IDX_MANUFACTURER_ID);
+                sink_info = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_SINK_INFO_DATA, 0);
+                put_unaligned_le16(sink_info, buf + 16);
+
+                snd_hda_codec_write(codec, nid, 0, ATI_VERB_SET_SINK_INFO_INDEX, ATI_INFO_IDX_PRODUCT_ID);
+                sink_info = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_SINK_INFO_DATA, 0);
+                put_unaligned_le16(sink_info, buf + 18);
+
+                snd_hda_codec_write(codec, nid, 0, ATI_VERB_SET_SINK_INFO_INDEX, ATI_INFO_IDX_SINK_DESC_LEN);
+                sink_desc_len = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_SINK_INFO_DATA, 0);
+
+                if (sink_desc_len > ELD_MAX_MNL) {
+                        snd_printd(KERN_INFO "HDMI ATI/AMD: Truncating HDMI sink description with length %d\n",
+                                   sink_desc_len);
+                        sink_desc_len = ELD_MAX_MNL;
+                }
+
+                buf[4] |= sink_desc_len;
+
+                for (i = 0; i < sink_desc_len; i++) {
+                        snd_hda_codec_write(codec, nid, 0, ATI_VERB_SET_SINK_INFO_INDEX, ATI_INFO_IDX_SINK_DESC_FIRST + i);
+                        buf[pos++] = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_SINK_INFO_DATA, 0);
+                }
+        }
+
+        for (i = AUDIO_CODING_TYPE_LPCM; i <= AUDIO_CODING_TYPE_WMAPRO; i++) {
+                if (i == AUDIO_CODING_TYPE_SACD || i == AUDIO_CODING_TYPE_DST)
+                        continue; /* not handled by ATI/AMD */
+
+                snd_hda_codec_write(codec, nid, 0, ATI_VERB_SET_AUDIO_DESCRIPTOR, i << 3);
+                ati_sad = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_AUDIO_DESCRIPTOR, 0);
+
+                if (ati_sad & ATI_AUDIODESC_RATES) {
+                        /* format is supported, copy SAD as-is */
+                        buf[pos++] = (ati_sad & 0x0000ff) >> 0;
+                        buf[pos++] = (ati_sad & 0x00ff00) >> 8;
+                        buf[pos++] = (ati_sad & 0xff0000) >> 16;
+                }
+
+                if (i == AUDIO_CODING_TYPE_LPCM
+                    && (ati_sad & ATI_AUDIODESC_LPCM_STEREO_RATES)
+                    && (ati_sad & ATI_AUDIODESC_LPCM_STEREO_RATES) >> 16 != (ati_sad & ATI_AUDIODESC_RATES)) {
+                        /* for PCM there is a separate stereo rate mask */
+                        buf[pos++] = ((ati_sad & 0x000000ff) & ~ATI_AUDIODESC_CHANNELS) | 0x1;
+                        /* rates from the extra byte */
+                        buf[pos++] = (ati_sad & 0xff000000) >> 24;
+                        buf[pos++] = (ati_sad & 0x00ff0000) >> 16;
+                }
+        }
+
+        if (pos == ELD_FIXED_BYTES + sink_desc_len) {
+                snd_printd(KERN_INFO "HDMI ATI/AMD: no audio descriptors for ELD\n");
+                return -EINVAL;
+        }
+
+        aud_synch = snd_hda_codec_read(codec, nid, 0, ATI_VERB_GET_AUDIO_VIDEO_DELAY, 0);
+        if ((aud_synch & ATI_DELAY_VIDEO_LATENCY) && (aud_synch & ATI_DELAY_AUDIO_LATENCY)) {
+                int video_latency = (aud_synch & ATI_DELAY_VIDEO_LATENCY) - 1;
+                int audio_latency = ((aud_synch & ATI_DELAY_AUDIO_LATENCY) >> 8) - 1;
+
+                if (video_latency > audio_latency)
+                        buf[6] = min(video_latency - audio_latency, 0xfa);
+        }
+
+        /* Baseline length */
+        buf[2] = pos - 4;
+
+        /* SAD count */
+        buf[5] |= ((pos - ELD_FIXED_BYTES - sink_desc_len) / 3) << 4;
+
+        *eld_size = pos;
+
+        return 0;
+}