Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / sound / drivers / mpu401 / mpu401_uart.c

diff --git a/sound/drivers/mpu401/mpu401_uart.c b/sound/drivers/mpu401/mpu401_uart.c
index 5993864..18cca24 100644 (file)
--- a/sound/drivers/mpu401/mpu401_uart.c
+++ b/sound/drivers/mpu401/mpu401_uart.c
@@ -49,12 +49,10 @@ static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu);
 
  */
 
-#define snd_mpu401_input_avail(mpu)    (!(mpu->read(mpu, MPU401C(mpu)) & 0x80))
-#define snd_mpu401_output_ready(mpu)   (!(mpu->read(mpu, MPU401C(mpu)) & 0x40))
-
-#define MPU401_RESET           0xff
-#define MPU401_ENTER_UART      0x3f
-#define MPU401_ACK             0xfe
+#define snd_mpu401_input_avail(mpu) \
+       (!(mpu->read(mpu, MPU401C(mpu)) & MPU401_RX_EMPTY))
+#define snd_mpu401_output_ready(mpu) \
+       (!(mpu->read(mpu, MPU401C(mpu)) & MPU401_TX_FULL))
 
 /* Build in lowlevel io */
 static void mpu401_write_port(struct snd_mpu401 *mpu, unsigned char data,
@@ -425,16 +423,17 @@ 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);