ALSA: firewire-digi00x: add proc node to show clock status

This commit adds proc node to show current clock status for debugging.

As long as testing Digi 002 rack, registers can show local clock rate,
local clock source. When external clock input such as S/PDIF is
connected, the registers show the detection and external clock rate.

Additionally, the registers show the mode of optical digital input
interface. Although, a tester with Digi 003 rack reports this makes no
sense. Further investigation is required for Digi 003 series.

Besides, in Digi 002 rack, the S/PDIF format must be IEC 60958-4,
so-called professional.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/digi00x/Makefile

-snd-firewire-digi00x-objs := amdtp-dot.o digi00x-stream.o digi00x.o
+snd-firewire-digi00x-objs := amdtp-dot.o digi00x-stream.o digi00x-proc.o \
+			     digi00x.o
 obj-$(CONFIG_SND_FIREWIRE_DIGI00X) += snd-firewire-digi00x.o

sound/firewire/digi00x/digi00x-proc.c

+/*
+ * digi00x-proc.c - a part of driver for Digidesign Digi 002/003 family
+ *
+ * Copyright (c) 2014-2015 Takashi Sakamoto
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+#include "digi00x.h"
+
+static int get_optical_iface_mode(struct snd_dg00x *dg00x,
+				  enum snd_dg00x_optical_mode *mode)
+{
+	__be32 data;
+	int err;
+
+	err = snd_fw_transaction(dg00x->unit, TCODE_READ_QUADLET_REQUEST,
+				 DG00X_ADDR_BASE + DG00X_OFFSET_OPT_IFACE_MODE,
+				 &data, sizeof(data), 0);
+	if (err >= 0)
+		*mode = be32_to_cpu(data) & 0x01;
+
+	return err;
+}
+
+static void proc_read_clock(struct snd_info_entry *entry,
+			    struct snd_info_buffer *buf)
+{
+	static const char *const source_name[] = {
+		[SND_DG00X_CLOCK_INTERNAL] = "internal",
+		[SND_DG00X_CLOCK_SPDIF] = "s/pdif",
+		[SND_DG00X_CLOCK_ADAT] = "adat",
+		[SND_DG00X_CLOCK_WORD] = "word clock",
+	};
+	static const char *const optical_name[] = {
+		[SND_DG00X_OPT_IFACE_MODE_ADAT] = "adat",
+		[SND_DG00X_OPT_IFACE_MODE_SPDIF] = "s/pdif",
+	};
+	struct snd_dg00x *dg00x = entry->private_data;
+	enum snd_dg00x_optical_mode mode;
+	unsigned int rate;
+	enum snd_dg00x_clock clock;
+	bool detect;
+
+	if (get_optical_iface_mode(dg00x, &mode) < 0)
+		return;
+	if (snd_dg00x_stream_get_local_rate(dg00x, &rate) < 0)
+		return;
+	if (snd_dg00x_stream_get_clock(dg00x, &clock) < 0)
+		return;
+
+	snd_iprintf(buf, "Optical mode: %s\n", optical_name[mode]);
+	snd_iprintf(buf, "Sampling Rate: %d\n", rate);
+	snd_iprintf(buf, "Clock Source: %s\n", source_name[clock]);
+
+	if (clock == SND_DG00X_CLOCK_INTERNAL)
+		return;
+
+	if (snd_dg00x_stream_check_external_clock(dg00x, &detect) < 0)
+		return;
+	snd_iprintf(buf, "External source: %s\n", detect ? "detected" : "not");
+	if (!detect)
+		return;
+
+	if (snd_dg00x_stream_get_external_rate(dg00x, &rate) >= 0)
+		snd_iprintf(buf, "External sampling rate: %d\n", rate);
+}
+
+void snd_dg00x_proc_init(struct snd_dg00x *dg00x)
+{
+	struct snd_info_entry *root, *entry;
+
+	/*
+	 * All nodes are automatically removed at snd_card_disconnect(),
+	 * by following to link list.
+	 */
+	root = snd_info_create_card_entry(dg00x->card, "firewire",
+					  dg00x->card->proc_root);
+	if (root == NULL)
+		return;
+
+	root->mode = S_IFDIR | S_IRUGO | S_IXUGO;
+	if (snd_info_register(root) < 0) {
+		snd_info_free_entry(root);
+		return;
+	}
+
+	entry = snd_info_create_card_entry(dg00x->card, "clock", root);
+	if (entry == NULL) {
+		snd_info_free_entry(root);
+		return;
+	}
+
+	snd_info_set_text_ops(entry, dg00x, proc_read_clock);
+	if (snd_info_register(entry) < 0) {
+		snd_info_free_entry(entry);
+		snd_info_free_entry(root);
+	}
+}

sound/firewire/digi00x/digi00x.c

@@ -81,6 +81,8 @@ static int snd_dg00x_probe(struct fw_unit *unit,
 	if (err < 0)
 		goto error;
 
+	snd_dg00x_proc_init(dg00x);
+
 	err = snd_card_register(card);
 	if (err < 0)
 		goto error;

sound/firewire/digi00x/digi00x.h

@@ -19,6 +19,7 @@
 
 #include <sound/core.h>
 #include <sound/initval.h>
+#include <sound/info.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 
@@ -84,6 +85,12 @@ enum snd_dg00x_clock {
 	SND_DG00X_CLOCK_COUNT,
 };
 
+enum snd_dg00x_optical_mode {
+	SND_DG00X_OPT_IFACE_MODE_ADAT = 0,
+	SND_DG00X_OPT_IFACE_MODE_SPDIF,
+	SND_DG00X_OPT_IFACE_MODE_COUNT,
+};
+
 int amdtp_dot_init(struct amdtp_stream *s, struct fw_unit *unit,
 		   enum amdtp_stream_direction dir);
 int amdtp_dot_set_parameters(struct amdtp_stream *s, unsigned int rate,
@@ -111,4 +118,5 @@ void snd_dg00x_stream_stop_duplex(struct snd_dg00x *dg00x);
 void snd_dg00x_stream_update_duplex(struct snd_dg00x *dg00x);
 void snd_dg00x_stream_destroy_duplex(struct snd_dg00x *dg00x);
 
+void snd_dg00x_proc_init(struct snd_dg00x *dg00x);
 #endif