aboutsummaryrefslogtreecommitdiffstats
path: root/sound/drivers/mpu401
diff options
context:
space:
mode:
authorClemens Ladisch <clemens@ladisch.de>2007-10-11 08:15:06 -0400
committerJaroslav Kysela <perex@perex.cz>2007-10-16 10:51:12 -0400
commit69d8d3eb4df40194485b842c00047bb80e51c6a8 (patch)
treee48e26bdd60fd05029c23a63104a3c98d7969cc4 /sound/drivers/mpu401
parent11be265f7fd4976a1139d6ec9b2ef1e8adaf835f (diff)
[ALSA] mpu-401: do not require an ACK byte for the ENTER_UART command
The original MPU-401 does not send an ACK byte after processing the ENTER_UART command, so we better do not try to wait for it. Many clones get this wrong and do send an ACK, but when interpreting it as MIDI, it is just a harmless Active Sensing message, and it is likely to be read and discarded by the interrupt handler before the MIDI input device is triggered. Signed-off-by: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Jaroslav Kysela <perex@suse.cz>
Diffstat (limited to 'sound/drivers/mpu401')
-rw-r--r--sound/drivers/mpu401/mpu401_uart.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/sound/drivers/mpu401/mpu401_uart.c b/sound/drivers/mpu401/mpu401_uart.c
index 85aedc348e2d..b5c5dd1e61bd 100644
--- a/sound/drivers/mpu401/mpu401_uart.c
+++ b/sound/drivers/mpu401/mpu401_uart.c
@@ -271,7 +271,7 @@ static int snd_mpu401_do_reset(struct snd_mpu401 *mpu)
271 if (snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1)) 271 if (snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1))
272 return -EIO; 272 return -EIO;
273 if (!(mpu->info_flags & MPU401_INFO_UART_ONLY) && 273 if (!(mpu->info_flags & MPU401_INFO_UART_ONLY) &&
274 snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 1)) 274 snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 0))
275 return -EIO; 275 return -EIO;
276 return 0; 276 return 0;
277} 277}