[ALSA] mtpav - Use platform_device
authorTakashi Iwai <tiwai@suse.de>
Thu, 17 Nov 2005 15:02:15 +0000 (16:02 +0100)
committerJaroslav Kysela <perex@suse.cz>
Tue, 3 Jan 2006 11:20:32 +0000 (12:20 +0100)
Modules: Generic drivers

Rewrite the probe/remove code using platform_device.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/drivers/mtpav.c

index d32d5f6eee392da3efdc8e844e3e3a15dd8ee9d5..d9c4e224fa5fdd57cb18ab6ea1fbe74aa6b72e58 100644 (file)
@@ -53,6 +53,8 @@
 #include <sound/driver.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/ioport.h>
 #include <linux/moduleparam.h>
@@ -125,16 +127,16 @@ MODULE_PARM_DESC(hwports, "Hardware ports # for MotuMTPAV MIDI.");
 /*
  */
 
-typedef struct mtpav_port {
+struct mtpav_port {
        u8 number;
        u8 hwport;
        u8 mode;
        u8 running_status;
        struct snd_rawmidi_substream *input;
        struct snd_rawmidi_substream *output;
-} mtpav_port_t;
+};
 
-typedef struct mtpav {
+struct mtpav {
        struct snd_card *card;
        unsigned long port;
        struct resource *res_port;
@@ -145,21 +147,15 @@ typedef struct mtpav {
        struct timer_list timer;        /* timer interrupts for outputs */
        struct snd_rawmidi *rmidi;
        int num_ports;          /* number of hw ports (1-8) */
-       mtpav_port_t ports[NUMPORTS];   /* all ports including computer, adat and bc */
+       struct mtpav_port ports[NUMPORTS];      /* all ports including computer, adat and bc */
 
        u32 inmidiport;         /* selected input midi port */
        u32 inmidistate;        /* during midi command 0xf5 */
 
        u32 outmidihwport;      /* selected output midi hw port */
-} mtpav_t;
+};
 
 
-/*
- * global instance
- * hey, we handle at most only one card..
- */
-static mtpav_t *mtp_card;
-
 /*
  * possible hardware ports (selected by 0xf5 port message)
  *      0x00           all ports
@@ -183,7 +179,7 @@ static mtpav_t *mtp_card;
 #define MTPAV_PIDX_BROADCAST   2
 
 
-static int translate_subdevice_to_hwport(mtpav_t *chip, int subdev)
+static int translate_subdevice_to_hwport(struct mtpav *chip, int subdev)
 {
        if (subdev < 0)
                return 0x01; /* invalid - use port 0 as default */
@@ -198,7 +194,7 @@ static int translate_subdevice_to_hwport(mtpav_t *chip, int subdev)
        return 0; /* all ports */
 }
 
-static int translate_hwport_to_subdevice(mtpav_t *chip, int hwport)
+static int translate_hwport_to_subdevice(struct mtpav *chip, int hwport)
 {
        int p;
        if (hwport <= 0x00) /* all ports */
@@ -223,7 +219,7 @@ static int translate_hwport_to_subdevice(mtpav_t *chip, int hwport)
 /*
  */
 
-static u8 snd_mtpav_getreg(mtpav_t *chip, u16 reg)
+static u8 snd_mtpav_getreg(struct mtpav *chip, u16 reg)
 {
        u8 rval = 0;
 
@@ -241,19 +237,16 @@ static u8 snd_mtpav_getreg(mtpav_t *chip, u16 reg)
 /*
  */
 
-static void snd_mtpav_mputreg(mtpav_t *chip, u16 reg, u8 val)
+static inline void snd_mtpav_mputreg(struct mtpav *chip, u16 reg, u8 val)
 {
-       if (reg == DREG) {
-               outb(val, chip->port + DREG);
-       } else if (reg == CREG) {
-               outb(val, chip->port + CREG);
-       }
+       if (reg == DREG || reg == CREG)
+               outb(val, chip->port + reg);
 }
 
 /*
  */
 
-static void snd_mtpav_wait_rfdhi(mtpav_t *chip)
+static void snd_mtpav_wait_rfdhi(struct mtpav *chip)
 {
        int counts = 10000;
        u8 sbyte;
@@ -265,7 +258,7 @@ static void snd_mtpav_wait_rfdhi(mtpav_t *chip)
        }
 }
 
-static void snd_mtpav_send_byte(mtpav_t *chip, u8 byte)
+static void snd_mtpav_send_byte(struct mtpav *chip, u8 byte)
 {
        u8 tcbyt;
        u8 clrwrite;
@@ -291,7 +284,8 @@ static void snd_mtpav_send_byte(mtpav_t *chip, u8 byte)
  */
 
 /* call this with spin lock held */
-static void snd_mtpav_output_port_write(mtpav_port_t *port,
+static void snd_mtpav_output_port_write(struct mtpav *mtp_card,
+                                       struct mtpav_port *portp,
                                        struct snd_rawmidi_substream *substream)
 {
        u8 outbyte;
@@ -303,22 +297,22 @@ static void snd_mtpav_output_port_write(mtpav_port_t *port,
 
        // send port change command if necessary
 
-       if (port->hwport != mtp_card->outmidihwport) {
-               mtp_card->outmidihwport = port->hwport;
+       if (portp->hwport != mtp_card->outmidihwport) {
+               mtp_card->outmidihwport = portp->hwport;
 
                snd_mtpav_send_byte(mtp_card, 0xf5);
-               snd_mtpav_send_byte(mtp_card, port->hwport);
-               //snd_printk("new outport: 0x%x\n", (unsigned int) port->hwport);
+               snd_mtpav_send_byte(mtp_card, portp->hwport);
+               //snd_printk("new outport: 0x%x\n", (unsigned int) portp->hwport);
 
-               if (!(outbyte & 0x80) && port->running_status)
-                       snd_mtpav_send_byte(mtp_card, port->running_status);
+               if (!(outbyte & 0x80) && portp->running_status)
+                       snd_mtpav_send_byte(mtp_card, portp->running_status);
        }
 
        // send data
 
        do {
                if (outbyte & 0x80)
-                       port->running_status = outbyte;
+                       portp->running_status = outbyte;
                
                snd_mtpav_send_byte(mtp_card, outbyte);
        } while (snd_rawmidi_transmit(substream, &outbyte, 1) == 1);
@@ -326,11 +320,12 @@ static void snd_mtpav_output_port_write(mtpav_port_t *port,
 
 static void snd_mtpav_output_write(struct snd_rawmidi_substream *substream)
 {
-       mtpav_port_t *port = &mtp_card->ports[substream->number];
+       struct mtpav *mtp_card = substream->rmidi->private_data;
+       struct mtpav_port *portp = &mtp_card->ports[substream->number];
        unsigned long flags;
 
        spin_lock_irqsave(&mtp_card->spinlock, flags);
-       snd_mtpav_output_port_write(port, substream);
+       snd_mtpav_output_port_write(mtp_card, portp, substream);
        spin_unlock_irqrestore(&mtp_card->spinlock, flags);
 }
 
@@ -339,7 +334,7 @@ static void snd_mtpav_output_write(struct snd_rawmidi_substream *substream)
  *      mtpav control
  */
 
-static void snd_mtpav_portscan(mtpav_t *chip)  // put mtp into smart routing mode
+static void snd_mtpav_portscan(struct mtpav *chip)     // put mtp into smart routing mode
 {
        u8 p;
 
@@ -355,10 +350,10 @@ static void snd_mtpav_portscan(mtpav_t *chip)     // put mtp into smart routing mode
 
 static int snd_mtpav_input_open(struct snd_rawmidi_substream *substream)
 {
+       struct mtpav *mtp_card = substream->rmidi->private_data;
+       struct mtpav_port *portp = &mtp_card->ports[substream->number];
        unsigned long flags;
-       mtpav_port_t *portp = &mtp_card->ports[substream->number];
 
-       //printk("mtpav port: %d opened\n", (int) substream->number);
        spin_lock_irqsave(&mtp_card->spinlock, flags);
        portp->mode |= MTPAV_MODE_INPUT_OPENED;
        portp->input = substream;
@@ -373,18 +368,15 @@ static int snd_mtpav_input_open(struct snd_rawmidi_substream *substream)
 
 static int snd_mtpav_input_close(struct snd_rawmidi_substream *substream)
 {
+       struct mtpav *mtp_card = substream->rmidi->private_data;
+       struct mtpav_port *portp = &mtp_card->ports[substream->number];
        unsigned long flags;
-       mtpav_port_t *portp = &mtp_card->ports[substream->number];
-
-       //printk("mtpav port: %d closed\n", (int) portp);
 
        spin_lock_irqsave(&mtp_card->spinlock, flags);
-
-       portp->mode &= (~MTPAV_MODE_INPUT_OPENED);
+       portp->mode &= ~MTPAV_MODE_INPUT_OPENED;
        portp->input = NULL;
        if (--mtp_card->share_irq == 0)
                snd_mtpav_mputreg(mtp_card, CREG, 0);   // disable pport interrupts
-
        spin_unlock_irqrestore(&mtp_card->spinlock, flags);
        return 0;
 }
@@ -394,8 +386,9 @@ static int snd_mtpav_input_close(struct snd_rawmidi_substream *substream)
 
 static void snd_mtpav_input_trigger(struct snd_rawmidi_substream *substream, int up)
 {
+       struct mtpav *mtp_card = substream->rmidi->private_data;
+       struct mtpav_port *portp = &mtp_card->ports[substream->number];
        unsigned long flags;
-       mtpav_port_t *portp = &mtp_card->ports[substream->number];
 
        spin_lock_irqsave(&mtp_card->spinlock, flags);
        if (up)
@@ -414,7 +407,7 @@ static void snd_mtpav_input_trigger(struct snd_rawmidi_substream *substream, int
 static void snd_mtpav_output_timer(unsigned long data)
 {
        unsigned long flags;
-       mtpav_t *chip = (mtpav_t *)data;
+       struct mtpav *chip = (struct mtpav *)data;
        int p;
 
        spin_lock_irqsave(&chip->spinlock, flags);
@@ -423,25 +416,22 @@ static void snd_mtpav_output_timer(unsigned long data)
        add_timer(&chip->timer);
        /* process each port */
        for (p = 0; p <= chip->num_ports * 2 + MTPAV_PIDX_BROADCAST; p++) {
-               mtpav_port_t *portp = &mtp_card->ports[p];
+               struct mtpav_port *portp = &chip->ports[p];
                if ((portp->mode & MTPAV_MODE_OUTPUT_TRIGGERED) && portp->output)
-                       snd_mtpav_output_port_write(portp, portp->output);
+                       snd_mtpav_output_port_write(chip, portp, portp->output);
        }
        spin_unlock_irqrestore(&chip->spinlock, flags);
 }
 
 /* spinlock held! */
-static void snd_mtpav_add_output_timer(mtpav_t *chip)
+static void snd_mtpav_add_output_timer(struct mtpav *chip)
 {
-       init_timer(&chip->timer);
-       chip->timer.function = snd_mtpav_output_timer;
-       chip->timer.data = (unsigned long) mtp_card;
        chip->timer.expires = 1 + jiffies;
        add_timer(&chip->timer);
 }
 
 /* spinlock held! */
-static void snd_mtpav_remove_output_timer(mtpav_t *chip)
+static void snd_mtpav_remove_output_timer(struct mtpav *chip)
 {
        del_timer(&chip->timer);
 }
@@ -451,8 +441,9 @@ static void snd_mtpav_remove_output_timer(mtpav_t *chip)
 
 static int snd_mtpav_output_open(struct snd_rawmidi_substream *substream)
 {
+       struct mtpav *mtp_card = substream->rmidi->private_data;
+       struct mtpav_port *portp = &mtp_card->ports[substream->number];
        unsigned long flags;
-       mtpav_port_t *portp = &mtp_card->ports[substream->number];
 
        spin_lock_irqsave(&mtp_card->spinlock, flags);
        portp->mode |= MTPAV_MODE_OUTPUT_OPENED;
@@ -466,11 +457,12 @@ static int snd_mtpav_output_open(struct snd_rawmidi_substream *substream)
 
 static int snd_mtpav_output_close(struct snd_rawmidi_substream *substream)
 {
+       struct mtpav *mtp_card = substream->rmidi->private_data;
+       struct mtpav_port *portp = &mtp_card->ports[substream->number];
        unsigned long flags;
-       mtpav_port_t *portp = &mtp_card->ports[substream->number];
 
        spin_lock_irqsave(&mtp_card->spinlock, flags);
-       portp->mode &= (~MTPAV_MODE_OUTPUT_OPENED);
+       portp->mode &= ~MTPAV_MODE_OUTPUT_OPENED;
        portp->output = NULL;
        spin_unlock_irqrestore(&mtp_card->spinlock, flags);
        return 0;
@@ -481,12 +473,13 @@ static int snd_mtpav_output_close(struct snd_rawmidi_substream *substream)
 
 static void snd_mtpav_output_trigger(struct snd_rawmidi_substream *substream, int up)
 {
+       struct mtpav *mtp_card = substream->rmidi->private_data;
+       struct mtpav_port *portp = &mtp_card->ports[substream->number];
        unsigned long flags;
-       mtpav_port_t *portp = &mtp_card->ports[substream->number];
 
        spin_lock_irqsave(&mtp_card->spinlock, flags);
        if (up) {
-               if (! (portp->mode  & MTPAV_MODE_OUTPUT_TRIGGERED)) {
+               if (! (portp->mode & MTPAV_MODE_OUTPUT_TRIGGERED)) {
                        if (mtp_card->istimer++ == 0)
                                snd_mtpav_add_output_timer(mtp_card);
                        portp->mode |= MTPAV_MODE_OUTPUT_TRIGGERED;
@@ -506,23 +499,20 @@ static void snd_mtpav_output_trigger(struct snd_rawmidi_substream *substream, in
  * midi interrupt for inputs
  */
 
-static void snd_mtpav_inmidi_process(mtpav_t *mcrd, u8 inbyte)
+static void snd_mtpav_inmidi_process(struct mtpav *mcrd, u8 inbyte)
 {
-       mtpav_port_t *portp;
+       struct mtpav_port *portp;
 
        if ((int)mcrd->inmidiport > mcrd->num_ports * 2 + MTPAV_PIDX_BROADCAST)
                return;
 
        portp = &mcrd->ports[mcrd->inmidiport];
-       if (portp->mode & MTPAV_MODE_INPUT_TRIGGERED) {
+       if (portp->mode & MTPAV_MODE_INPUT_TRIGGERED)
                snd_rawmidi_receive(portp->input, &inbyte, 1);
-       }
 }
 
-static void snd_mtpav_inmidi_h(mtpav_t * mcrd, u8 inbyte)
+static void snd_mtpav_inmidi_h(struct mtpav *mcrd, u8 inbyte)
 {
-       snd_assert(mcrd, return);
-
        if (inbyte >= 0xf8) {
                /* real-time midi code */
                snd_mtpav_inmidi_process(mcrd, inbyte);
@@ -540,7 +530,7 @@ static void snd_mtpav_inmidi_h(mtpav_t * mcrd, u8 inbyte)
        }
 }
 
-static void snd_mtpav_read_bytes(mtpav_t * mcrd)
+static void snd_mtpav_read_bytes(struct mtpav *mcrd)
 {
        u8 clrread, setread;
        u8 mtp_read_byte;
@@ -580,9 +570,8 @@ static void snd_mtpav_read_bytes(mtpav_t * mcrd)
 
 static irqreturn_t snd_mtpav_irqh(int irq, void *dev_id, struct pt_regs *regs)
 {
-       mtpav_t *mcard = dev_id;
+       struct mtpav *mcard = dev_id;
 
-       //printk("irqh()\n");
        spin_lock(&mcard->spinlock);
        snd_mtpav_read_bytes(mcard);
        spin_unlock(&mcard->spinlock);
@@ -592,14 +581,14 @@ static irqreturn_t snd_mtpav_irqh(int irq, void *dev_id, struct pt_regs *regs)
 /*
  * get ISA resources
  */
-static int snd_mtpav_get_ISA(mtpav_t * mcard)
+static int __init snd_mtpav_get_ISA(struct mtpav * mcard)
 {
        if ((mcard->res_port = request_region(port, 3, "MotuMTPAV MIDI")) == NULL) {
                snd_printk("MTVAP port 0x%lx is busy\n", port);
                return -EBUSY;
        }
        mcard->port = port;
-       if (request_irq(irq, snd_mtpav_irqh, SA_INTERRUPT, "MOTU MTPAV", (void *)mcard)) {
+       if (request_irq(irq, snd_mtpav_irqh, SA_INTERRUPT, "MOTU MTPAV", mcard)) {
                snd_printk("MTVAP IRQ %d busy\n", irq);
                return -EBUSY;
        }
@@ -628,7 +617,8 @@ static struct snd_rawmidi_ops snd_mtpav_input = {
  * get RAWMIDI resources
  */
 
-static void snd_mtpav_set_name(mtpav_t *chip, struct snd_rawmidi_substream *substream)
+static void __init snd_mtpav_set_name(struct mtpav *chip,
+                                     struct snd_rawmidi_substream *substream)
 {
        if (substream->number >= 0 && substream->number < chip->num_ports)
                sprintf(substream->name, "MTP direct %d", (substream->number % chip->num_ports) + 1);
@@ -642,21 +632,18 @@ static void snd_mtpav_set_name(mtpav_t *chip, struct snd_rawmidi_substream *subs
                strcpy(substream->name, "MTP broadcast");
 }
 
-static int snd_mtpav_get_RAWMIDI(mtpav_t * mcard)
+static int __init snd_mtpav_get_RAWMIDI(struct mtpav *mcard)
 {
-       int rval = 0;
+       int rval;
        struct snd_rawmidi *rawmidi;
        struct snd_rawmidi_substream *substream;
        struct list_head *list;
 
-       //printk("entering snd_mtpav_get_RAWMIDI\n");
-
        if (hwports < 1)
-               mcard->num_ports = 1;
+               hwports = 1;
        else if (hwports > 8)
-               mcard->num_ports = 8;
-       else
-               mcard->num_ports = hwports;
+               hwports = 8;
+       mcard->num_ports = hwports;
 
        if ((rval = snd_rawmidi_new(mcard->card, "MotuMIDI", 0,
                                    mcard->num_ports * 2 + MTPAV_PIDX_BROADCAST + 1,
@@ -664,6 +651,7 @@ static int snd_mtpav_get_RAWMIDI(mtpav_t * mcard)
                                    &mcard->rmidi)) < 0)
                return rval;
        rawmidi = mcard->rmidi;
+       rawmidi->private_data = mcard;
 
        list_for_each(list, &rawmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams) {
                substream = list_entry(list, struct snd_rawmidi_substream, list);
@@ -679,36 +667,15 @@ static int snd_mtpav_get_RAWMIDI(mtpav_t * mcard)
        rawmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT | SNDRV_RAWMIDI_INFO_INPUT |
                               SNDRV_RAWMIDI_INFO_DUPLEX;
        sprintf(rawmidi->name, "MTP AV MIDI");
-       //printk("exiting snd_mtpav_get_RAWMIDI() \n");
        return 0;
 }
 
 /*
  */
 
-static mtpav_t *new_mtpav(void)
-{
-       mtpav_t *ncrd = kzalloc(sizeof(*ncrd), GFP_KERNEL);
-       if (ncrd != NULL) {
-               spin_lock_init(&ncrd->spinlock);
-
-               init_timer(&ncrd->timer);
-               ncrd->card = NULL;
-               ncrd->irq = -1;
-               ncrd->share_irq = 0;
-
-               ncrd->inmidiport = 0xffffffff;
-               ncrd->inmidistate = 0;
-               ncrd->outmidihwport = 0xffffffff;
-       }
-       return ncrd;
-}
-
-/*
- */
-
-static void free_mtpav(mtpav_t * crd)
+static void snd_mtpav_free(struct snd_card *card)
 {
+       struct mtpav *crd = card->private_data;
        unsigned long flags;
 
        spin_lock_irqsave(&crd->spinlock, flags);
@@ -718,78 +685,101 @@ static void free_mtpav(mtpav_t * crd)
        if (crd->irq >= 0)
                free_irq(crd->irq, (void *)crd);
        release_and_free_resource(crd->res_port);
-       kfree(crd);
 }
 
 /*
  */
-
-static int __init alsa_card_mtpav_init(void)
+static int __init snd_mtpav_probe(struct platform_device *dev)
 {
-       int err = 0;
-       char longname_buffer[80];
+       struct snd_card *card;
+       int err;
+       struct mtpav *mtp_card;
 
-       mtp_card = new_mtpav();
-       if (mtp_card == NULL)
+       card = snd_card_new(index, id, THIS_MODULE, sizeof(*mtp_card));
+       if (! card)
                return -ENOMEM;
 
-       mtp_card->card = snd_card_new(index, id, THIS_MODULE, 0);
-       if (mtp_card->card == NULL) {
-               free_mtpav(mtp_card);
-               return -ENOMEM;
-       }
+       mtp_card = card->private_data;
+       spin_lock_init(&mtp_card->spinlock);
+       init_timer(&mtp_card->timer);
+       mtp_card->card = card;
+       mtp_card->irq = -1;
+       mtp_card->share_irq = 0;
+       mtp_card->inmidiport = 0xffffffff;
+       mtp_card->inmidistate = 0;
+       mtp_card->outmidihwport = 0xffffffff;
+       init_timer(&mtp_card->timer);
+       mtp_card->timer.function = snd_mtpav_output_timer;
+       mtp_card->timer.data = (unsigned long) mtp_card;
+
+       card->private_free = snd_mtpav_free;
 
        err = snd_mtpav_get_ISA(mtp_card);
-       //printk("snd_mtpav_get_ISA returned: %d\n", err);
        if (err < 0)
                goto __error;
 
-       strcpy(mtp_card->card->driver, "MTPAV");
-       strcpy(mtp_card->card->shortname, "MTPAV on parallel port");
-       memset(longname_buffer, 0, sizeof(longname_buffer));
-       sprintf(longname_buffer, "MTPAV on parallel port at");
+       strcpy(card->driver, "MTPAV");
+       strcpy(card->shortname, "MTPAV on parallel port");
+       snprintf(card->longname, sizeof(card->longname),
+                "MTPAV on parallel port at 0x%lx", port);
 
        err = snd_mtpav_get_RAWMIDI(mtp_card);
-       //snd_printk("snd_mtapv_get_RAWMIDI returned: %d\n", err);
        if (err < 0)
                goto __error;
 
-       if ((err = snd_card_set_generic_dev(mtp_card->card)) < 0)
-               goto __error;
-
-       err = snd_card_register(mtp_card->card);        // don't snd_card_register until AFTER all cards reources done!
+       snd_mtpav_portscan(mtp_card);
 
-       //printk("snd_card_register returned %d\n", err);
+       snd_card_set_dev(card, &dev->dev);
+       err = snd_card_register(mtp_card->card);
        if (err < 0)
                goto __error;
 
-
-       snd_mtpav_portscan(mtp_card);
-
+       platform_set_drvdata(dev, card);
        printk(KERN_INFO "Motu MidiTimePiece on parallel port irq: %d ioport: 0x%lx\n", irq, port);
-
        return 0;
 
-      __error:
-       snd_card_free(mtp_card->card);
-       free_mtpav(mtp_card);
+ __error:
+       snd_card_free(card);
        return err;
 }
 
-/*
- */
+static int snd_mtpav_remove(struct platform_device *devptr)
+{
+       snd_card_free(platform_get_drvdata(devptr));
+       platform_set_drvdata(devptr, NULL);
+       return 0;
+}
 
-static void __exit alsa_card_mtpav_exit(void)
+#define SND_MTPAV_DRIVER       "snd_mtpav"
+
+static struct platform_driver snd_mtpav_driver = {
+       .probe          = snd_mtpav_probe,
+       .remove         = snd_mtpav_remove,
+       .driver         = {
+               .name   = SND_MTPAV_DRIVER
+       },
+};
+
+static int __init alsa_card_mtpav_init(void)
 {
-       if (mtp_card == NULL)
-               return;
-       if (mtp_card->card)
-               snd_card_free(mtp_card->card);
-       free_mtpav(mtp_card);
+       int err;
+       struct platform_device *device;
+
+       if ((err = platform_driver_register(&snd_mtpav_driver)) < 0)
+               return err;
+
+       device = platform_device_register_simple(SND_MTPAV_DRIVER, -1, NULL, 0);
+       if (IS_ERR(device)) {
+               platform_driver_unregister(&snd_mtpav_driver);
+               return PTR_ERR(device);
+       }
+       return 0;
 }
 
-/*
- */
+static void __exit alsa_card_mtpav_exit(void)
+{
+       platform_driver_unregister(&snd_mtpav_driver);
+}
 
 module_init(alsa_card_mtpav_init)
 module_exit(alsa_card_mtpav_exit)