1 files changed, 230 insertions, 0 deletions
diff --git a/sound/hda/codecs/hdmi/eld.c b/sound/hda/codecs/hdmi/eld.c
new file mode 100644
index 000000000000..1464fd1c675b
--- /dev/null
+++ b/sound/hda/codecs/hdmi/eld.c
@@ -0,0 +1,230 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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>
+ */
+
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <sound/core.h>
+#include <sound/hda_chmap.h>
+#include <sound/hda_codec.h>
+#include "hda_local.h"
+
+enum cea_edid_versions {
+	CEA_EDID_VER_NONE	= 0,
+	CEA_EDID_VER_CEA861	= 1,
+	CEA_EDID_VER_CEA861A	= 2,
+	CEA_EDID_VER_CEA861BCD	= 3,
+	CEA_EDID_VER_RESERVED	= 4,
+};
+
+/*
+ * The following two lists are shared between
+ * 	- HDMI audio InfoFrame (source to sink)
+ * 	- CEA E-EDID Extension (sink to source)
+ */
+
+static unsigned int hdmi_get_eld_data(struct hda_codec *codec, hda_nid_t nid,
+					int byte_index)
+{
+	unsigned int val;
+
+	val = snd_hda_codec_read(codec, nid, 0,
+					AC_VERB_GET_HDMI_ELDD, byte_index);
+#ifdef BE_PARANOID
+	codec_info(codec, "HDMI: ELD data byte %d: 0x%x\n", byte_index, val);
+#endif
+	return val;
+}
+
+int snd_hdmi_get_eld_size(struct hda_codec *codec, hda_nid_t nid)
+{
+	return snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_HDMI_DIP_SIZE,
+						 AC_DIPSIZE_ELD_BUF);
+}
+
+int snd_hdmi_get_eld(struct hda_codec *codec, hda_nid_t nid,
+		     unsigned char *buf, int *eld_size)
+{
+	int i;
+	int ret = 0;
+	int size;
+
+	/*
+	 * ELD size is initialized to zero in caller function. If no errors and
+	 * ELD is valid, actual eld_size is assigned.
+	 */
+
+	size = snd_hdmi_get_eld_size(codec, nid);
+	if (size == 0) {
+		/* wfg: workaround for ASUS P5E-VM HDMI board */
+		codec_info(codec, "HDMI: ELD buf size is 0, force 128\n");
+		size = 128;
+	}
+	if (size < ELD_FIXED_BYTES || size > ELD_MAX_SIZE) {
+		codec_info(codec, "HDMI: invalid ELD buf size %d\n", size);
+		return -ERANGE;
+	}
+
+	/* set ELD buffer */
+	for (i = 0; i < size; i++) {
+		unsigned int val = hdmi_get_eld_data(codec, nid, i);
+		/*
+		 * Graphics driver might be writing to ELD buffer right now.
+		 * Just abort. The caller will repoll after a while.
+		 */
+		if (!(val & AC_ELDD_ELD_VALID)) {
+			codec_info(codec, "HDMI: invalid ELD data byte %d\n", i);
+			ret = -EINVAL;
+			goto error;
+		}
+		val &= AC_ELDD_ELD_DATA;
+		/*
+		 * The first byte cannot be zero. This can happen on some DVI
+		 * connections. Some Intel chips may also need some 250ms delay
+		 * to return non-zero ELD data, even when the graphics driver
+		 * correctly writes ELD content before setting ELD_valid bit.
+		 */
+		if (!val && !i) {
+			codec_dbg(codec, "HDMI: 0 ELD data\n");
+			ret = -EINVAL;
+			goto error;
+		}
+		buf[i] = val;
+	}
+
+	*eld_size = size;
+error:
+	return ret;
+}
+
+#ifdef CONFIG_SND_PROC_FS
+void snd_hdmi_print_eld_info(struct hdmi_eld *eld,
+			     struct snd_info_buffer *buffer,
+			     hda_nid_t pin_nid, int dev_id, hda_nid_t cvt_nid)
+{
+	snd_iprintf(buffer, "monitor_present\t\t%d\n", eld->monitor_present);
+	snd_iprintf(buffer, "eld_valid\t\t%d\n", eld->eld_valid);
+	snd_iprintf(buffer, "codec_pin_nid\t\t0x%x\n", pin_nid);
+	snd_iprintf(buffer, "codec_dev_id\t\t0x%x\n", dev_id);
+	snd_iprintf(buffer, "codec_cvt_nid\t\t0x%x\n", cvt_nid);
+
+	if (!eld->eld_valid)
+		return;
+
+	snd_print_eld_info(&eld->info, buffer);
+}
+
+void snd_hdmi_write_eld_info(struct hdmi_eld *eld,
+			     struct snd_info_buffer *buffer)
+{
+	struct snd_parsed_hdmi_eld *e = &eld->info;
+	char line[64];
+	char name[64];
+	char *sname;
+	long long val;
+	unsigned int n;
+
+	while (!snd_info_get_line(buffer, line, sizeof(line))) {
+		if (sscanf(line, "%s %llx", name, &val) != 2)
+			continue;
+		/*
+		 * We don't allow modification to these fields:
+		 * 	monitor_name manufacture_id product_id
+		 * 	eld_version edid_version
+		 */
+		if (!strcmp(name, "monitor_present"))
+			eld->monitor_present = val;
+		else if (!strcmp(name, "eld_valid"))
+			eld->eld_valid = val;
+		else if (!strcmp(name, "connection_type"))
+			e->conn_type = val;
+		else if (!strcmp(name, "port_id"))
+			e->port_id = val;
+		else if (!strcmp(name, "support_hdcp"))
+			e->support_hdcp = val;
+		else if (!strcmp(name, "support_ai"))
+			e->support_ai = val;
+		else if (!strcmp(name, "audio_sync_delay"))
+			e->aud_synch_delay = val;
+		else if (!strcmp(name, "speakers"))
+			e->spk_alloc = val;
+		else if (!strcmp(name, "sad_count"))
+			e->sad_count = val;
+		else if (!strncmp(name, "sad", 3)) {
+			sname = name + 4;
+			n = name[3] - '0';
+			if (name[4] >= '0' && name[4] <= '9') {
+				sname++;
+				n = 10 * n + name[4] - '0';
+			}
+			if (n >= ELD_MAX_SAD)
+				continue;
+			if (!strcmp(sname, "_coding_type"))
+				e->sad[n].format = val;
+			else if (!strcmp(sname, "_channels"))
+				e->sad[n].channels = val;
+			else if (!strcmp(sname, "_rates"))
+				e->sad[n].rates = val;
+			else if (!strcmp(sname, "_bits"))
+				e->sad[n].sample_bits = val;
+			else if (!strcmp(sname, "_max_bitrate"))
+				e->sad[n].max_bitrate = val;
+			else if (!strcmp(sname, "_profile"))
+				e->sad[n].profile = val;
+			if (n >= e->sad_count)
+				e->sad_count = n + 1;
+		}
+	}
+}
+#endif /* CONFIG_SND_PROC_FS */
+
+/* update PCM info based on ELD */
+void snd_hdmi_eld_update_pcm_info(struct snd_parsed_hdmi_eld *e,
+			      struct hda_pcm_stream *hinfo)
+{
+	u32 rates;
+	u64 formats;
+	unsigned int maxbps;
+	unsigned int channels_max;
+	int i;
+
+	/* assume basic audio support (the basic audio flag is not in ELD;
+	 * however, all audio capable sinks are required to support basic
+	 * audio) */
+	rates = SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 |
+		SNDRV_PCM_RATE_48000;
+	formats = SNDRV_PCM_FMTBIT_S16_LE;
+	maxbps = 16;
+	channels_max = 2;
+	for (i = 0; i < e->sad_count; i++) {
+		struct snd_cea_sad *a = &e->sad[i];
+		rates |= a->rates;
+		if (a->channels > channels_max)
+			channels_max = a->channels;
+		if (a->format == AUDIO_CODING_TYPE_LPCM) {
+			if (a->sample_bits & ELD_PCM_BITS_20) {
+				formats |= SNDRV_PCM_FMTBIT_S32_LE;
+				if (maxbps < 20)
+					maxbps = 20;
+			}
+			if (a->sample_bits & ELD_PCM_BITS_24) {
+				formats |= SNDRV_PCM_FMTBIT_S32_LE;
+				if (maxbps < 24)
+					maxbps = 24;
+			}
+		}
+	}
+
+	/* restrict the parameters by the values the codec provides */
+	hinfo->rates &= rates;
+	hinfo->formats &= formats;
+	hinfo->maxbps = min(hinfo->maxbps, maxbps);
+	hinfo->channels_max = min(hinfo->channels_max, channels_max);
+}