3 files changed, 40 insertions, 28 deletions

diff --git a/sound/firewire/dice/dice-interface.h b/sound/firewire/dice/dice-interface.h
index 15a484b05298..9cad3d608229 100644
--- a/sound/firewire/dice/dice-interface.h
+++ b/sound/firewire/dice/dice-interface.h
@@ -175,13 +175,18 @@
 #define GLOBAL_SAMPLE_RATE		0x05c
 
 /*
+ * Some old firmware versions do not have the following global registers.
+ * Windows drivers produced by TCAT lost backward compatibility in its
+ * early release because they can handle firmware only which supports the
+ * following registers.
+ */
+
+/*
  * The version of the DICE driver specification that this device conforms to;
  * read-only.
  */
 #define GLOBAL_VERSION			0x060
 
-/* Some old firmware versions do not have the following global registers: */
-
 /*
  * Supported sample rates and clock sources; read-only.
  */
diff --git a/sound/firewire/dice/dice-proc.c b/sound/firewire/dice/dice-proc.c
index f5c1d1bced59..cc079323ed30 100644
--- a/sound/firewire/dice/dice-proc.c
+++ b/sound/firewire/dice/dice-proc.c
@@ -148,12 +148,12 @@ static void dice_proc_read(struct snd_info_entry *entry,
 				   >> CLOCK_RATE_SHIFT));
 	snd_iprintf(buffer, "  ext status: %08x\n", buf.global.extended_status);
 	snd_iprintf(buffer, "  sample rate: %u\n", buf.global.sample_rate);
-	snd_iprintf(buffer, "  version: %u.%u.%u.%u\n",
-		    (buf.global.version >> 24) & 0xff,
-		    (buf.global.version >> 16) & 0xff,
-		    (buf.global.version >>  8) & 0xff,
-		    (buf.global.version >>  0) & 0xff);
 	if (quadlets >= 90) {
+		snd_iprintf(buffer, "  version: %u.%u.%u.%u\n",
+			    (buf.global.version >> 24) & 0xff,
+			    (buf.global.version >> 16) & 0xff,
+			    (buf.global.version >>  8) & 0xff,
+			    (buf.global.version >>  0) & 0xff);
 		snd_iprintf(buffer, "  clock caps:");
 		for (i = 0; i <= 6; ++i)
 			if (buf.global.clock_caps & (1 << i))
diff --git a/sound/firewire/dice/dice-transaction.c b/sound/firewire/dice/dice-transaction.c
index 0f0350320ae8..b7e138b5abcf 100644
--- a/sound/firewire/dice/dice-transaction.c
+++ b/sound/firewire/dice/dice-transaction.c
@@ -265,7 +265,7 @@ int snd_dice_transaction_reinit(struct snd_dice *dice)
 static int get_subaddrs(struct snd_dice *dice)
 {
 	static const int min_values[10] = {
-		10, 0x64 / 4,
+		10, 0x60 / 4,
 		10, 0x18 / 4,
 		10, 0x18 / 4,
 		0, 0,
@@ -301,33 +301,40 @@ static int get_subaddrs(struct snd_dice *dice)
 		}
 	}
 
-	/*
-	 * Check that the implemented DICE driver specification major version
-	 * number matches.
-	 */
-	err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,
-				 DICE_PRIVATE_SPACE +
-				 be32_to_cpu(pointers[0]) * 4 + GLOBAL_VERSION,
-				 &version, sizeof(version), 0);
-	if (err < 0)
-		goto end;
+	if (be32_to_cpu(pointers[1]) > 0x18) {
+		/*
+		 * Check that the implemented DICE driver specification major
+		 * version number matches.
+		 */
+		err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,
+				DICE_PRIVATE_SPACE +
+				be32_to_cpu(pointers[0]) * 4 + GLOBAL_VERSION,
+				&version, sizeof(version), 0);
+		if (err < 0)
+			goto end;
 
-	if ((version & cpu_to_be32(0xff000000)) != cpu_to_be32(0x01000000)) {
-		dev_err(&dice->unit->device,
-			"unknown DICE version: 0x%08x\n", be32_to_cpu(version));
-		err = -ENODEV;
-		goto end;
+		if ((version & cpu_to_be32(0xff000000)) !=
+						cpu_to_be32(0x01000000)) {
+			dev_err(&dice->unit->device,
+				"unknown DICE version: 0x%08x\n",
+				be32_to_cpu(version));
+			err = -ENODEV;
+			goto end;
+		}
+
+		/* Set up later. */
+		dice->clock_caps = 1;
 	}
 
 	dice->global_offset = be32_to_cpu(pointers[0]) * 4;
 	dice->tx_offset = be32_to_cpu(pointers[2]) * 4;
 	dice->rx_offset = be32_to_cpu(pointers[4]) * 4;
-	dice->sync_offset = be32_to_cpu(pointers[6]) * 4;
-	dice->rsrv_offset = be32_to_cpu(pointers[8]) * 4;
 
-	/* Set up later. */
-	if (be32_to_cpu(pointers[1]) * 4 >= GLOBAL_CLOCK_CAPABILITIES + 4)
-		dice->clock_caps = 1;
+	/* Old firmware doesn't support these fields. */
+	if (pointers[7])
+		dice->sync_offset = be32_to_cpu(pointers[6]) * 4;
+	if (pointers[9])
+		dice->rsrv_offset = be32_to_cpu(pointers[8]) * 4;
 end:
 	kfree(pointers);
 	return err;