1 files changed, 194 insertions, 97 deletions

diff --git a/sound/drivers/mpu401/mpu401_uart.c b/sound/drivers/mpu401/mpu401_uart.c
index 8687ae3c66b..e3a90d043f0 100644
--- a/sound/drivers/mpu401/mpu401_uart.c
+++ b/sound/drivers/mpu401/mpu401_uart.c
@@ -1,9 +1,9 @@
 /*
- *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
+ *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  *  Routines for control of MPU-401 in UART mode
  *
  *  MPU-401 supports UART mode which is not capable generate transmit
- *  interrupts thus output is done via polling. Also, if irq < 0, then
+ *  interrupts thus output is done via polling. Without interrupt,
  *  input is done also via polling. Do not expect good performance.
  *
  *
@@ -28,18 +28,18 @@
  *
  */
 
-#include <sound/driver.h>
 #include <asm/io.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/ioport.h>
+#include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/errno.h>
 #include <sound/core.h>
 #include <sound/mpu401.h>
 
-MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>");
+MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
 MODULE_DESCRIPTION("Routines for control of MPU-401 in UART mode");
 MODULE_LICENSE("GPL");
 
@@ -50,30 +50,32 @@ 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, unsigned long addr)
+static void mpu401_write_port(struct snd_mpu401 *mpu, unsigned char data,
+			      unsigned long addr)
 {
 	outb(data, addr);
 }
 
-static unsigned char mpu401_read_port(struct snd_mpu401 *mpu, unsigned long addr)
+static unsigned char mpu401_read_port(struct snd_mpu401 *mpu,
+				      unsigned long addr)
 {
 	return inb(addr);
 }
 
-static void mpu401_write_mmio(struct snd_mpu401 *mpu, unsigned char data, unsigned long addr)
+static void mpu401_write_mmio(struct snd_mpu401 *mpu, unsigned char data,
+			      unsigned long addr)
 {
 	writeb(data, (void __iomem *)addr);
 }
 
-static unsigned char mpu401_read_mmio(struct snd_mpu401 *mpu, unsigned long addr)
+static unsigned char mpu401_read_mmio(struct snd_mpu401 *mpu,
+				      unsigned long addr)
 {
 	return readb((void __iomem *)addr);
 }
@@ -86,37 +88,51 @@ static void snd_mpu401_uart_clear_rx(struct snd_mpu401 *mpu)
 		mpu->read(mpu, MPU401D(mpu));
 #ifdef CONFIG_SND_DEBUG
 	if (timeout <= 0)
-		snd_printk("cmd: clear rx timeout (status = 0x%x)\n", mpu->read(mpu, MPU401C(mpu)));
+		snd_printk(KERN_ERR "cmd: clear rx timeout (status = 0x%x)\n",
+			   mpu->read(mpu, MPU401C(mpu)));
 #endif
 }
 
-static void _snd_mpu401_uart_interrupt(struct snd_mpu401 *mpu)
+static void uart_interrupt_tx(struct snd_mpu401 *mpu)
 {
-	spin_lock(&mpu->input_lock);
-	if (test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
-		snd_mpu401_uart_input_read(mpu);
-	} else {
-		snd_mpu401_uart_clear_rx(mpu);
-	}
-	spin_unlock(&mpu->input_lock);
- 	/* ok. for better Tx performance try do some output when input is done */
+	unsigned long flags;
+
 	if (test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode) &&
 	    test_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode)) {
-		spin_lock(&mpu->output_lock);
+		spin_lock_irqsave(&mpu->output_lock, flags);
 		snd_mpu401_uart_output_write(mpu);
-		spin_unlock(&mpu->output_lock);
+		spin_unlock_irqrestore(&mpu->output_lock, flags);
 	}
 }
 
+static void _snd_mpu401_uart_interrupt(struct snd_mpu401 *mpu)
+{
+	unsigned long flags;
+
+	if (mpu->info_flags & MPU401_INFO_INPUT) {
+		spin_lock_irqsave(&mpu->input_lock, flags);
+		if (test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
+			snd_mpu401_uart_input_read(mpu);
+		else
+			snd_mpu401_uart_clear_rx(mpu);
+		spin_unlock_irqrestore(&mpu->input_lock, flags);
+	}
+	if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
+		/* ok. for better Tx performance try do some output
+		   when input is done */
+		uart_interrupt_tx(mpu);
+}
+
 /**
  * snd_mpu401_uart_interrupt - generic MPU401-UART interrupt handler
  * @irq: the irq number
  * @dev_id: mpu401 instance
- * @regs: the reigster
  *
  * Processes the interrupt for MPU401-UART i/o.
+ *
+ * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
  */
-irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id)
 {
 	struct snd_mpu401 *mpu = dev_id;
 	
@@ -126,6 +142,29 @@ irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id, struct pt_regs *reg
 	return IRQ_HANDLED;
 }
 
+EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
+
+/**
+ * snd_mpu401_uart_interrupt_tx - generic MPU401-UART transmit irq handler
+ * @irq: the irq number
+ * @dev_id: mpu401 instance
+ *
+ * Processes the interrupt for MPU401-UART output.
+ *
+ * Return: %IRQ_HANDLED if the interrupt was handled. %IRQ_NONE otherwise.
+ */
+irqreturn_t snd_mpu401_uart_interrupt_tx(int irq, void *dev_id)
+{
+	struct snd_mpu401 *mpu = dev_id;
+	
+	if (mpu == NULL)
+		return IRQ_NONE;
+	uart_interrupt_tx(mpu);
+	return IRQ_HANDLED;
+}
+
+EXPORT_SYMBOL(snd_mpu401_uart_interrupt_tx);
+
 /*
  * timer callback
  * reprogram the timer and call the interrupt job
@@ -159,7 +198,8 @@ static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input)
 		mpu->timer.expires = 1 + jiffies;
 		add_timer(&mpu->timer);
 	} 
-	mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER : MPU401_MODE_OUTPUT_TIMER;
+	mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER :
+		MPU401_MODE_OUTPUT_TIMER;
 	spin_unlock_irqrestore (&mpu->timer_lock, flags);
 }
 
@@ -172,7 +212,8 @@ static void snd_mpu401_uart_remove_timer (struct snd_mpu401 *mpu, int input)
 
 	spin_lock_irqsave (&mpu->timer_lock, flags);
 	if (mpu->timer_invoked) {
-		mpu->timer_invoked &= input ? ~MPU401_MODE_INPUT_TIMER : ~MPU401_MODE_OUTPUT_TIMER;
+		mpu->timer_invoked &= input ? ~MPU401_MODE_INPUT_TIMER :
+			~MPU401_MODE_OUTPUT_TIMER;
 		if (! mpu->timer_invoked)
 			del_timer(&mpu->timer);
 	}
@@ -180,10 +221,12 @@ static void snd_mpu401_uart_remove_timer (struct snd_mpu401 *mpu, int input)
 }
 
 /*
-
+ * send a UART command
+ * return zero if successful, non-zero for some errors
  */
 
-static void snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd, int ack)
+static int snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd,
+			       int ack)
 {
 	unsigned long flags;
 	int timeout, ok;
@@ -195,15 +238,17 @@ static void snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd, int
 	}
 	/* ok. standard MPU-401 initialization */
 	if (mpu->hardware != MPU401_HW_SB) {
-		for (timeout = 1000; timeout > 0 && !snd_mpu401_output_ready(mpu); timeout--)
+		for (timeout = 1000; timeout > 0 &&
+			     !snd_mpu401_output_ready(mpu); timeout--)
 			udelay(10);
 #ifdef CONFIG_SND_DEBUG
 		if (!timeout)
-			snd_printk("cmd: tx timeout (status = 0x%x)\n", mpu->read(mpu, MPU401C(mpu)));
+			snd_printk(KERN_ERR "cmd: tx timeout (status = 0x%x)\n",
+				   mpu->read(mpu, MPU401C(mpu)));
 #endif
 	}
 	mpu->write(mpu, cmd, MPU401C(mpu));
-	if (ack) {
+	if (ack && !(mpu->info_flags & MPU401_INFO_NO_ACK)) {
 		ok = 0;
 		timeout = 10000;
 		while (!ok && timeout-- > 0) {
@@ -214,13 +259,26 @@ static void snd_mpu401_uart_cmd(struct snd_mpu401 * mpu, unsigned char cmd, int
 		}
 		if (!ok && mpu->read(mpu, MPU401D(mpu)) == MPU401_ACK)
 			ok = 1;
-	} else {
+	} else
 		ok = 1;
-	}
 	spin_unlock_irqrestore(&mpu->input_lock, flags);
-	if (! ok)
-		snd_printk("cmd: 0x%x failed at 0x%lx (status = 0x%x, data = 0x%x)\n", cmd, mpu->port, mpu->read(mpu, MPU401C(mpu)), mpu->read(mpu, MPU401D(mpu)));
-	// snd_printk("cmd: 0x%x at 0x%lx (status = 0x%x, data = 0x%x)\n", cmd, mpu->port, mpu->read(mpu, MPU401C(mpu)), mpu->read(mpu, MPU401D(mpu)));
+	if (!ok) {
+		snd_printk(KERN_ERR "cmd: 0x%x failed at 0x%lx "
+			   "(status = 0x%x, data = 0x%x)\n", cmd, mpu->port,
+			   mpu->read(mpu, MPU401C(mpu)),
+			   mpu->read(mpu, MPU401D(mpu)));
+		return 1;
+	}
+	return 0;
+}
+
+static int snd_mpu401_do_reset(struct snd_mpu401 *mpu)
+{
+	if (snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1))
+		return -EIO;
+	if (snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 0))
+		return -EIO;
+	return 0;
 }
 
 /*
@@ -235,12 +293,17 @@ static int snd_mpu401_uart_input_open(struct snd_rawmidi_substream *substream)
 	if (mpu->open_input && (err = mpu->open_input(mpu)) < 0)
 		return err;
 	if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode)) {
-		snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1);
-		snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 1);
+		if (snd_mpu401_do_reset(mpu) < 0)
+			goto error_out;
 	}
 	mpu->substream_input = substream;
 	set_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
 	return 0;
+
+error_out:
+	if (mpu->open_input && mpu->close_input)
+		mpu->close_input(mpu);
+	return -EIO;
 }
 
 static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream *substream)
@@ -252,46 +315,58 @@ static int snd_mpu401_uart_output_open(struct snd_rawmidi_substream *substream)
 	if (mpu->open_output && (err = mpu->open_output(mpu)) < 0)
 		return err;
 	if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode)) {
-		snd_mpu401_uart_cmd(mpu, MPU401_RESET, 1);
-		snd_mpu401_uart_cmd(mpu, MPU401_ENTER_UART, 1);
+		if (snd_mpu401_do_reset(mpu) < 0)
+			goto error_out;
 	}
 	mpu->substream_output = substream;
 	set_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
 	return 0;
+
+error_out:
+	if (mpu->open_output && mpu->close_output)
+		mpu->close_output(mpu);
+	return -EIO;
 }
 
 static int snd_mpu401_uart_input_close(struct snd_rawmidi_substream *substream)
 {
 	struct snd_mpu401 *mpu;
+	int err = 0;
 
 	mpu = substream->rmidi->private_data;
 	clear_bit(MPU401_MODE_BIT_INPUT, &mpu->mode);
 	mpu->substream_input = NULL;
 	if (! test_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode))
-		snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
+		err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
 	if (mpu->close_input)
 		mpu->close_input(mpu);
+	if (err)
+		return -EIO;
 	return 0;
 }
 
 static int snd_mpu401_uart_output_close(struct snd_rawmidi_substream *substream)
 {
 	struct snd_mpu401 *mpu;
+	int err = 0;
 
 	mpu = substream->rmidi->private_data;
 	clear_bit(MPU401_MODE_BIT_OUTPUT, &mpu->mode);
 	mpu->substream_output = NULL;
 	if (! test_bit(MPU401_MODE_BIT_INPUT, &mpu->mode))
-		snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
+		err = snd_mpu401_uart_cmd(mpu, MPU401_RESET, 0);
 	if (mpu->close_output)
 		mpu->close_output(mpu);
+	if (err)
+		return -EIO;
 	return 0;
 }
 
 /*
  * trigger input callback
  */
-static void snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
+static void
+snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substream, int up)
 {
 	unsigned long flags;
 	struct snd_mpu401 *mpu;
@@ -299,11 +374,12 @@ static void snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substrea
 
 	mpu = substream->rmidi->private_data;
 	if (up) {
-		if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode)) {
+		if (! test_and_set_bit(MPU401_MODE_BIT_INPUT_TRIGGER,
+				       &mpu->mode)) {
 			/* first time - flush FIFO */
 			while (max-- > 0)
 				mpu->read(mpu, MPU401D(mpu));
-			if (mpu->irq < 0)
+			if (mpu->info_flags & MPU401_INFO_USE_TIMER)
 				snd_mpu401_uart_add_timer(mpu, 1);
 		}
 		
@@ -312,10 +388,11 @@ static void snd_mpu401_uart_input_trigger(struct snd_rawmidi_substream *substrea
 		snd_mpu401_uart_input_read(mpu);
 		spin_unlock_irqrestore(&mpu->input_lock, flags);
 	} else {
-		if (mpu->irq < 0)
+		if (mpu->info_flags & MPU401_INFO_USE_TIMER)
 			snd_mpu401_uart_remove_timer(mpu, 1);
 		clear_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode);
 	}
+
 }
 
 /*
@@ -328,13 +405,11 @@ static void snd_mpu401_uart_input_read(struct snd_mpu401 * mpu)
 	unsigned char byte;
 
 	while (max-- > 0) {
-		if (snd_mpu401_input_avail(mpu)) {
-			byte = mpu->read(mpu, MPU401D(mpu));
-			if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode))
-				snd_rawmidi_receive(mpu->substream_input, &byte, 1);
-		} else {
+		if (! snd_mpu401_input_avail(mpu))
 			break; /* input not available */
-		}
+		byte = mpu->read(mpu, MPU401D(mpu));
+		if (test_bit(MPU401_MODE_BIT_INPUT_TRIGGER, &mpu->mode))
+			snd_rawmidi_receive(mpu->substream_input, &byte, 1);
 	}
 }
 
@@ -353,19 +428,20 @@ 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)) {
-					mpu->write(mpu, byte, MPU401D(mpu));
-					snd_rawmidi_transmit_ack(mpu->substream_output, 1);
-					break;
-				}
-			}
-			if (timeout == 0)
+		if (snd_rawmidi_transmit_peek(mpu->substream_output,
+					      &byte, 1) == 1) {
+			/*
+			 * 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);
 		} else {
 			snd_mpu401_uart_remove_timer (mpu, 0);
 			break;	/* no other data - leave the tx loop */
@@ -376,7 +452,8 @@ static void snd_mpu401_uart_output_write(struct snd_mpu401 * mpu)
 /*
  * output trigger callback
  */
-static void snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
+static void
+snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substream, int up)
 {
 	unsigned long flags;
 	struct snd_mpu401 *mpu;
@@ -389,14 +466,16 @@ static void snd_mpu401_uart_output_trigger(struct snd_rawmidi_substream *substre
 		 * since the output timer might have been removed in
 		 * snd_mpu401_uart_output_write().
 		 */
-		snd_mpu401_uart_add_timer(mpu, 0);
+		if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
+			snd_mpu401_uart_add_timer(mpu, 0);
 
 		/* output pending data */
 		spin_lock_irqsave(&mpu->output_lock, flags);
 		snd_mpu401_uart_output_write(mpu);
 		spin_unlock_irqrestore(&mpu->output_lock, flags);
 	} else {
-		snd_mpu401_uart_remove_timer(mpu, 0);
+		if (! (mpu->info_flags & MPU401_INFO_TX_IRQ))
+			snd_mpu401_uart_remove_timer(mpu, 0);
 		clear_bit(MPU401_MODE_BIT_OUTPUT_TRIGGER, &mpu->mode);
 	}
 }
@@ -422,7 +501,7 @@ static struct snd_rawmidi_ops snd_mpu401_uart_input =
 static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
 {
 	struct snd_mpu401 *mpu = rmidi->private_data;
-	if (mpu->irq_flags && mpu->irq >= 0)
+	if (mpu->irq >= 0)
 		free_irq(mpu->irq, (void *) mpu);
 	release_and_free_resource(mpu->res);
 	kfree(mpu);
@@ -434,9 +513,8 @@ static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
  * @device: the device index, zero-based
  * @hardware: the hardware type, MPU401_HW_XXXX
  * @port: the base address of MPU401 port
- * @integrated: non-zero if the port was already reserved by the chip
- * @irq: the irq number, -1 if no interrupt for mpu
- * @irq_flags: the irq request flags (SA_XXX), 0 if irq was already reserved.
+ * @info_flags: bitflags MPU401_INFO_XXX
+ * @irq: the ISA irq number, -1 if not to be allocated
  * @rrawmidi: the pointer to store the new rawmidi instance
  *
  * Creates a new MPU-401 instance.
@@ -445,21 +523,28 @@ static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi)
  * not the mpu401 instance itself.  To access to the mpu401 instance,
  * cast from rawmidi->private_data (with struct snd_mpu401 magic-cast).
  *
- * Returns zero if successful, or a negative error code.
+ * Return: Zero if successful, or a negative error code.
  */
 int snd_mpu401_uart_new(struct snd_card *card, int device,
 			unsigned short hardware,
-			unsigned long port, int integrated,
-			int irq, int irq_flags,
+			unsigned long port,
+			unsigned int info_flags,
+			int irq,
 			struct snd_rawmidi ** rrawmidi)
 {
 	struct snd_mpu401 *mpu;
 	struct snd_rawmidi *rmidi;
+	int in_enable, out_enable;
 	int err;
 
 	if (rrawmidi)
 		*rrawmidi = NULL;
-	if ((err = snd_rawmidi_new(card, "MPU-401U", device, 1, 1, &rmidi)) < 0)
+	if (! (info_flags & (MPU401_INFO_INPUT | MPU401_INFO_OUTPUT)))
+		info_flags |= MPU401_INFO_INPUT | MPU401_INFO_OUTPUT;
+	in_enable = (info_flags & MPU401_INFO_INPUT) ? 1 : 0;
+	out_enable = (info_flags & MPU401_INFO_OUTPUT) ? 1 : 0;
+	if ((err = snd_rawmidi_new(card, "MPU-401U", device,
+				   out_enable, in_enable, &rmidi)) < 0)
 		return err;
 	mpu = kzalloc(sizeof(*mpu), GFP_KERNEL);
 	if (mpu == NULL) {
@@ -473,54 +558,66 @@ int snd_mpu401_uart_new(struct snd_card *card, int device,
 	spin_lock_init(&mpu->output_lock);
 	spin_lock_init(&mpu->timer_lock);
 	mpu->hardware = hardware;
-	if (!integrated) {
+	mpu->irq = -1;
+	if (! (info_flags & MPU401_INFO_INTEGRATED)) {
 		int res_size = hardware == MPU401_HW_PC98II ? 4 : 2;
-		if ((mpu->res = request_region(port, res_size, "MPU401 UART")) == NULL) {
-			snd_printk(KERN_ERR "mpu401_uart: unable to grab port 0x%lx size %d\n", port, res_size);
+		mpu->res = request_region(port, res_size, "MPU401 UART");
+		if (mpu->res == NULL) {
+			snd_printk(KERN_ERR "mpu401_uart: "
+				   "unable to grab port 0x%lx size %d\n",
+				   port, res_size);
 			snd_device_free(card, rmidi);
 			return -EBUSY;
 		}
 	}
-	switch (hardware) {
-	case MPU401_HW_AUREAL:
+	if (info_flags & MPU401_INFO_MMIO) {
 		mpu->write = mpu401_write_mmio;
 		mpu->read = mpu401_read_mmio;
-		break;
-	default:
+	} else {
 		mpu->write = mpu401_write_port;
 		mpu->read = mpu401_read_port;
-		break;
 	}
 	mpu->port = port;
 	if (hardware == MPU401_HW_PC98II)
 		mpu->cport = port + 2;
 	else
 		mpu->cport = port + 1;
-	if (irq >= 0 && irq_flags) {
-		if (request_irq(irq, snd_mpu401_uart_interrupt, irq_flags, "MPU401 UART", (void *) mpu)) {
-			snd_printk(KERN_ERR "mpu401_uart: unable to grab IRQ %d\n", irq);
+	if (irq >= 0) {
+		if (request_irq(irq, snd_mpu401_uart_interrupt, 0,
+				"MPU401 UART", (void *) mpu)) {
+			snd_printk(KERN_ERR "mpu401_uart: "
+				   "unable to grab IRQ %d\n", irq);
 			snd_device_free(card, rmidi);
 			return -EBUSY;
 		}
 	}
+	if (irq < 0 && !(info_flags & MPU401_INFO_IRQ_HOOK))
+		info_flags |= MPU401_INFO_USE_TIMER;
+	mpu->info_flags = info_flags;
 	mpu->irq = irq;
-	mpu->irq_flags = irq_flags;
 	if (card->shortname[0])
-		snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI", card->shortname);
+		snprintf(rmidi->name, sizeof(rmidi->name), "%s MIDI",
+			 card->shortname);
 	else
-		sprintf(rmidi->name, "MPU-401 MIDI %d-%d", card->number, device);
-	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_mpu401_uart_output);
-	snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_mpu401_uart_input);
-	rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT |
-	                     SNDRV_RAWMIDI_INFO_INPUT |
-	                     SNDRV_RAWMIDI_INFO_DUPLEX;
+		sprintf(rmidi->name, "MPU-401 MIDI %d-%d",card->number, device);
+	if (out_enable) {
+		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT,
+				    &snd_mpu401_uart_output);
+		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT;
+	}
+	if (in_enable) {
+		snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT,
+				    &snd_mpu401_uart_input);
+		rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT;
+		if (out_enable)
+			rmidi->info_flags |= SNDRV_RAWMIDI_INFO_DUPLEX;
+	}
 	mpu->rmidi = rmidi;
 	if (rrawmidi)
 		*rrawmidi = rmidi;
 	return 0;
 }
 
-EXPORT_SYMBOL(snd_mpu401_uart_interrupt);
 EXPORT_SYMBOL(snd_mpu401_uart_new);
 
 /*