From 4eb1ee7733f4e5d783fc389c8a415b034cfe988f Mon Sep 17 00:00:00 2001
From: Clemens Ladisch <clemens@ladisch.de>
Date: Mon, 25 Feb 2008 10:59:52 +0100
Subject: [PATCH] --- yaml --- r: 92071 b: refs/heads/master c:
 ea6b5828cdbbedaf26b12ae64befbec18084ea3c h: refs/heads/master i:   92069:
 6a33ab586ddfbba432ac850fa5633a6e048f95cd   92067:
 4f40440ff580e145a35f04f9f0d1342a7587eec3   92063:
 07a1c630aa61e28ad73f0bbbaba78ef17612f2b5 v: v3

---
 [refs]                                   |  2 +-
 trunk/sound/drivers/mpu401/mpu401_uart.c | 13 +++++++------
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index 95f943bed6ff..2acfb7a87877 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 47ba97f8fa01bb5b48e73b4b1271fbf1436a2d4b
+refs/heads/master: ea6b5828cdbbedaf26b12ae64befbec18084ea3c
diff --git a/trunk/sound/drivers/mpu401/mpu401_uart.c b/trunk/sound/drivers/mpu401/mpu401_uart.c
index 5993864acbd3..dd6ec4266732 100644
--- a/trunk/sound/drivers/mpu401/mpu401_uart.c
+++ b/trunk/sound/drivers/mpu401/mpu401_uart.c
@@ -425,16 +425,17 @@ static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu)
 static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu)
 {
 	unsigned char byte;
-	int max = 256, timeout;
+	int max = 256;
 
 	do {
 		if (snd_rawmidi_transmit_peek(mpu->substream_output,
 					      &byte, 1) == 1) {
-			for (timeout = 100; timeout > 0; timeout--) {
-				if (snd_mpu401_output_ready(mpu))
-					break;
-			}
-			if (timeout == 0)
+			/*
+			 * Try twice because there is hardware that insists on
+			 * setting the output busy bit after each write.
+			 */
+			if (!snd_mpu401_output_ready(mpu) &&
+			    !snd_mpu401_output_ready(mpu))
 				break;	/* Tx FIFO full - try again later */
 			mpu->write(mpu, byte, MPU401D(mpu));
 			snd_rawmidi_transmit_ack(mpu->substream_output, 1);