ASoC: qdsp6: q6apm: add voice-call blob-player prototype (FP6 bring-up)

Replay pre-generated APM command sequences (GRAPH_OPEN/SET_CFG/PREPARE/
START, mined from the stock FP6 ACDB by utilities/mkvoiceblobs.py)
through the q6apm GPR channel via
/sys/kernel/debug/q6apm-voice-proto/play.

Bring-up prototype for cellular voice-call audio: the replayed graphs
contain the VCPM voice config; the modem and the ADSP VCPM service
attach the vocoder to them once a call is active. Local carry only,
NOT for upstream (the upstreamable form will be topology-driven).

Assisted-by: Claude:claude-fable-5

sound/soc/qcom/qdsp6/Makefile

@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0-only
 snd-q6dsp-common-y := q6dsp-common.o q6dsp-lpass-ports.o q6dsp-lpass-clocks.o
-snd-q6apm-y := q6apm.o audioreach.o topology.o
+snd-q6apm-y := q6apm.o audioreach.o topology.o q6apm-voice-proto.o
 
 obj-$(CONFIG_SND_SOC_QDSP6_COMMON) += snd-q6dsp-common.o
 obj-$(CONFIG_SND_SOC_QDSP6_CORE) += q6core.o

sound/soc/qcom/qdsp6/q6apm-voice-proto.c

@@ -0,0 +1,156 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Voice-call bring-up prototype for the Fairphone (Gen. 6): replay
+ * pre-generated APM command sequences through the q6apm GPR channel.
+ *
+ * The blobs reproduce, byte for byte, the GRAPH_OPEN/SET_CFG/PREPARE/START
+ * sequence the stock Android PAL/AGM/GSL stack sends to set up the
+ * handset voice-call graphs (mined from the device ACDB; generated by
+ * utilities/mkvoiceblobs.py in the bring-up repo). The modem's voice
+ * engine and the ADSP VCPM service wire up the vocoder themselves once
+ * these graphs are running.
+ *
+ * Local prototype only, NOT for upstream. Interface:
+ *   echo <fw-file> > /sys/kernel/debug/q6apm-voice-proto/play
+ * where <fw-file> is relative to /lib/firmware. Playback aborts on the
+ * first command the DSP rejects.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/firmware.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/soc/qcom/apr.h>
+#include <linux/uaccess.h>
+#include <sound/soc.h>
+#include "audioreach.h"
+#include "q6apm.h"
+
+#define Q6VP_MAGIC	0x50563651	/* "Q6VP" little-endian */
+#define Q6VP_VERSION	1
+
+struct q6vp_hdr {
+	__le32 magic;
+	__le32 version;
+	__le32 num_records;
+} __packed;
+
+struct q6vp_rec {
+	__le32 opcode;
+	__le32 size;
+} __packed;
+
+static struct q6apm *q6vp_apm;
+static struct dentry *q6vp_dir;
+
+static int q6vp_send(uint32_t opcode, const void *payload, uint32_t size)
+{
+	struct gpr_pkt *pkt;
+	int ret;
+
+	pkt = audioreach_alloc_apm_cmd_pkt(size, opcode, 0);
+	if (IS_ERR(pkt))
+		return PTR_ERR(pkt);
+
+	memcpy((void *)pkt + GPR_HDR_SIZE + APM_CMD_HDR_SIZE, payload, size);
+
+	ret = q6apm_send_cmd_sync(q6vp_apm, pkt, 0);
+	kfree(pkt);
+
+	return ret;
+}
+
+static int q6vp_play(const char *name)
+{
+	const struct firmware *fw;
+	const struct q6vp_hdr *hdr;
+	const struct q6vp_rec *rec;
+	struct device *dev = q6vp_apm->dev;
+	size_t off;
+	uint32_t i, num, opcode, size;
+	int ret;
+
+	ret = request_firmware(&fw, name, dev);
+	if (ret) {
+		dev_err(dev, "voice-proto: cannot load %s (%d)\n", name, ret);
+		return ret;
+	}
+
+	hdr = (const struct q6vp_hdr *)fw->data;
+	if (fw->size < sizeof(*hdr) ||
+	    le32_to_cpu(hdr->magic) != Q6VP_MAGIC ||
+	    le32_to_cpu(hdr->version) != Q6VP_VERSION) {
+		dev_err(dev, "voice-proto: %s: bad header\n", name);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	num = le32_to_cpu(hdr->num_records);
+	off = sizeof(*hdr);
+	for (i = 0; i < num; i++) {
+		if (off + sizeof(*rec) > fw->size) {
+			ret = -EINVAL;
+			goto out;
+		}
+		rec = (const struct q6vp_rec *)(fw->data + off);
+		opcode = le32_to_cpu(rec->opcode);
+		size = le32_to_cpu(rec->size);
+		off += sizeof(*rec);
+		if (off + size > fw->size) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		ret = q6vp_send(opcode, fw->data + off, size);
+		dev_info(dev, "voice-proto: %s[%u] opcode 0x%08x size %u -> %d\n",
+			 name, i, opcode, size, ret);
+		if (ret)
+			goto out;
+
+		off += ALIGN(size, 4);
+	}
+
+out:
+	release_firmware(fw);
+	return ret;
+}
+
+static ssize_t q6vp_play_write(struct file *file, const char __user *ubuf,
+			       size_t count, loff_t *ppos)
+{
+	char name[128];
+	int ret;
+
+	if (!q6vp_apm)
+		return -ENODEV;
+	if (count >= sizeof(name))
+		return -EINVAL;
+	if (copy_from_user(name, ubuf, count))
+		return -EFAULT;
+	name[count] = '\0';
+	strim(name);
+
+	ret = q6vp_play(name);
+
+	return ret ? ret : count;
+}
+
+static const struct file_operations q6vp_play_fops = {
+	.open = simple_open,
+	.write = q6vp_play_write,
+	.llseek = default_llseek,
+};
+
+void q6apm_voice_proto_init(struct q6apm *apm)
+{
+	q6vp_apm = apm;
+	q6vp_dir = debugfs_create_dir("q6apm-voice-proto", NULL);
+	debugfs_create_file("play", 0200, q6vp_dir, NULL, &q6vp_play_fops);
+}
+
+void q6apm_voice_proto_exit(void)
+{
+	debugfs_remove_recursive(q6vp_dir);
+	q6vp_dir = NULL;
+	q6vp_apm = NULL;
+}

sound/soc/qcom/qdsp6/q6apm.c

@@ -764,6 +764,8 @@ static int apm_probe(gpr_device_t *gdev)
 
 	g_apm = apm;
 
+	q6apm_voice_proto_init(apm);
+
 	q6apm_get_apm_state(apm);
 
 	ret = snd_soc_register_component(dev, &q6apm_audio_component, NULL, 0);
@@ -781,6 +783,7 @@ static int apm_probe(gpr_device_t *gdev)
 
 static void apm_remove(gpr_device_t *gdev)
 {
+	q6apm_voice_proto_exit();
 	of_platform_depopulate(&gdev->dev);
 	snd_soc_unregister_component(&gdev->dev);
 }

sound/soc/qcom/qdsp6/q6apm.h

@@ -157,4 +157,8 @@ int q6apm_remove_initial_silence(struct device *dev, struct q6apm_graph *graph,
 int q6apm_remove_trailing_silence(struct device *dev, struct q6apm_graph *graph, uint32_t samples);
 int q6apm_set_real_module_id(struct device *dev, struct q6apm_graph *graph, uint32_t codec_id);
 int q6apm_get_hw_pointer(struct q6apm_graph *graph, int dir);
+
+/* FP6 voice-call bring-up prototype (q6apm-voice-proto.c) */
+void q6apm_voice_proto_init(struct q6apm *apm);
+void q6apm_voice_proto_exit(void);
 #endif /* __APM_GRAPH_ */