/* * Driver for Midiman Portman2x4 parallel port midi interface * * Copyright (c) by Levent Guendogdu * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * ChangeLog * Jan 24 2007 Matthias Koenig * - cleanup and rewrite * Sep 30 2004 Tobias Gehrig * - source code cleanup * Sep 03 2004 Tobias Gehrig * - fixed compilation problem with alsa 1.0.6a (removed MODULE_CLASSES, * MODULE_PARM_SYNTAX and changed MODULE_DEVICES to * MODULE_SUPPORTED_DEVICE) * Mar 24 2004 Tobias Gehrig * - added 2.6 kernel support * Mar 18 2004 Tobias Gehrig * - added parport_unregister_driver to the startup routine if the driver fails to detect a portman * - added support for all 4 output ports in portman_putmidi * Mar 17 2004 Tobias Gehrig * - added checks for opened input device in interrupt handler * Feb 20 2004 Tobias Gehrig * - ported from alsa 0.5 to 1.0 */ #include #include #include #include #include #include #include #include #include #define CARD_NAME "Portman 2x4" #define DRIVER_NAME "portman" #define PLATFORM_DRIVER "snd_portman2x4" static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP; static struct platform_device *platform_devices[SNDRV_CARDS]; static int device_count; module_param_array(index, int, NULL, S_IRUGO); MODULE_PARM_DESC(index, "Index value for " CARD_NAME " soundcard."); module_param_array(id, charp, NULL, S_IRUGO); MODULE_PARM_DESC(id, "ID string for " CARD_NAME " soundcard."); module_param_array(enable, bool, NULL, S_IRUGO); MODULE_PARM_DESC(enable, "Enable " CARD_NAME " soundcard."); MODULE_AUTHOR("Levent Guendogdu, Tobias Gehrig, Matthias Koenig"); MODULE_DESCRIPTION("Midiman Portman2x4"); MODULE_LICENSE("GPL"); MODULE_SUPPORTED_DEVICE("{{Midiman,Portman2x4}}"); /********************************************************************* * Chip specific *********************************************************************/ #define PORTMAN_NUM_INPUT_PORTS 2 #define PORTMAN_NUM_OUTPUT_PORTS 4 struct portman { spinlock_t reg_lock; struct snd_card *card; struct snd_rawmidi *rmidi; struct pardevice *pardev; int pardev_claimed; int open_count; int mode[PORTMAN_NUM_INPUT_PORTS]; struct snd_rawmidi_substream *midi_input[PORTMAN_NUM_INPUT_PORTS]; }; static int portman_free(struct portman *pm) { kfree(pm); return 0; } static int __devinit portman_create(struct snd_card *card, struct pardevice *pardev, struct portman **rchip) { struct portman *pm; *rchip = NULL; pm = kzalloc(sizeof(struct portman), GFP_KERNEL); if (pm == NULL) return -ENOMEM; /* Init chip specific data */ spin_lock_init(&pm->reg_lock); pm->card = card; pm->pardev = pardev; *rchip = pm; return 0; } /********************************************************************* * HW related constants *********************************************************************/ /* Standard PC parallel port status register equates. */ #define PP_STAT_BSY 0x80 /* Busy status. Inverted. */ #define PP_STAT_ACK 0x40 /* Acknowledge. Non-Inverted. */ #define PP_STAT_POUT 0x20 /* Paper Out. Non-Inverted. */ #define PP_STAT_SEL 0x10 /* Select. Non-Inverted. */ #define PP_STAT_ERR 0x08 /* Error. Non-Inverted. */ /* Standard PC parallel port command register equates. */ #define PP_CMD_IEN 0x10 /* IRQ Enable. Non-Inverted. */ #define PP_CMD_SELI 0x08 /* Select Input. Inverted. */ #define PP_CMD_INIT 0x04 /* Init Printer. Non-Inverted. */ #define PP_CMD_FEED 0x02 /* Auto Feed. Inverted. */ #define PP_CMD_STB 0x01 /* Strobe. Inverted. */ /* Parallel Port Command Register as implemented by PCP2x4. */ #define INT_EN PP_CMD_IEN /* Interrupt enable. */ #define STROBE PP_CMD_STB /* Command strobe. */ /* The parallel port command register field (b1..b3) selects the * various "registers" within the PC/P 2x4. These are the internal * address of these "registers" that must be written to the parallel * port command register. */ #define RXDATA0 (0 << 1) /* PCP RxData channel 0. */ #define RXDATA1 (1 << 1) /* PCP RxData channel 1. */ #define GEN_CTL (2 << 1) /* PCP General Control Register. */ #define SYNC_CTL (3 << 1) /* PCP Sync Control Register. */ #define TXDATA0 (4 << 1) /* PCP TxData channel 0. */ #define TXDATA1 (5 << 1) /* PCP TxData channel 1. */ #define TXDATA2 (6 << 1) /* PCP TxData channel 2. */ #define TXDATA3 (7 << 1) /* PCP TxData channel 3. */ /* Parallel Port Status Register as implemented by PCP2x4. */ #define ESTB PP_STAT_POUT /* Echoed strobe. */ #define INT_REQ PP_STAT_ACK /* Input data int request. */ #define BUSY PP_STAT_ERR /* Interface Busy. */ /* Parallel Port Status Register BUSY and SELECT lines are multiplexed * between several functions. Depending on which 2x4 "register" is * currently selected (b1..b3), the BUSY and SELECT lines are * assigned as follows: * * SELECT LINE: A3 A2 A1 * -------- */ #define RXAVAIL PP_STAT_SEL /* Rx Available, channel 0. 0 0 0 */ // RXAVAIL1 PP_STAT_SEL /* Rx Available, channel 1. 0 0 1 */ #define SYNC_STAT PP_STAT_SEL /* Reserved - Sync Status. 0 1 0 */ // /* Reserved. 0 1 1 */ #define TXEMPTY PP_STAT_SEL /* Tx Empty, channel 0. 1 0 0 */ // TXEMPTY1 PP_STAT_SEL /* Tx Empty, channel 1. 1 0 1 */ // TXEMPTY2 PP_STAT_SEL /* Tx Empty, channel 2. 1 1 0 */ // TXEMPTY3 PP_STAT_SEL /* Tx Empty, channel 3. 1 1 1 */ /* BUSY LINE: A3 A2 A1 * -------- */ #define RXDATA PP_STAT_BSY /* Rx Input Data, channel 0. 0 0 0 */ // RXDATA1 PP_STAT_BSY /* Rx Input Data, channel 1. 0 0 1 */ #define SYNC_DATA PP_STAT_BSY /* Reserved - Sync Data. 0 1 0 */ /* Reserved. 0 1 1 */ #define DATA_ECHO PP_STAT_BSY /* Parallel Port Data Echo. 1 0 0 */ #define A0_ECHO PP_STAT_BSY /* Address 0 Echo. 1 0 1 */ #define A1_ECHO PP_STAT_BSY /* Address 1 Echo. 1 1 0 */ #define A2_ECHO PP_STAT_BSY /* Address 2 Echo. 1 1 1 */ #define PORTMAN2X4_MODE_INPUT_TRIGGERED 0x01 /********************************************************************* * Hardware specific functions *********************************************************************/ static inline void portman_write_command(struct portman *pm, u8 value) { parport_write_control(pm->pardev->port, value); } static inline u8 portman_read_command(struct portman *pm) { return parport_read_control(pm->pardev->port); } static inline u8 portman_read_status(struct portman *pm) { return parport_read_status(pm->pardev->port); } static inline u8 portman_read_data(struct portman *pm) { return parport_read_data(pm->pardev->port); } static inline void portman_write_data(struct portman *pm, u8 value) { parport_write_data(pm->pardev->port, value); } static void portman_write_midi(struct portman *pm, int port, u8 mididata) { int command = ((port + 4) << 1); /* Get entering data byte and port number in BL and BH respectively. * Set up Tx Channel address field for use with PP Cmd Register. * Store address field in BH register. * Inputs: AH = Output port number (0..3). * AL = Data byte. * command = TXDATA0 | INT_EN; * Align port num with address field (b1...b3), * set address for TXDatax, Strobe=0 */ command |= INT_EN; /* Disable interrupts so that the process is not interrupted, then * write the address associated with the current Tx channel to the * PP Command Reg. Do not set the Strobe signal yet. */ do { portman_write_command(pm, command); /* While the address lines settle, write parallel output data to * PP Data Reg. This has no effect until Strobe signal is asserted. */ portman_write_data(pm, mididata); /* If PCP channel's TxEmpty is set (TxEmpty is read through the PP * Status Register), then go write data. Else go back and wait. */ } while ((portman_read_status(pm) & TXEMPTY) != TXEMPTY); /* TxEmpty is set. Maintain PC/P destination address and assert * Strobe through the PP Command Reg. This will Strobe data into * the PC/P transmitter and set the PC/P BUSY signal. */ portman_write_command(pm, command | STROBE); /* Wait for strobe line to settle and echo back through hardware. * Once it has echoed back, assume that the address and data lines * have settled! */ while ((portman_read_status(pm) & ESTB) == 0) cpu_relax(); /* Release strobe and immediately re-allow interrupts. */ portman_write_command(pm, command); while ((portman_read_status(pm) & ESTB) == ESTB) cpu_relax(); /* PC/P BUSY is now set. We must wait until BUSY resets itself. * We'll reenable ints while we're waiting. */ while ((portman_read_status(pm) & BUSY) == BUSY) cpu_relax(); /* Data sent. */ } /* * Read MIDI byte from port * Attempt to read input byte from specified hardware input port (0..). * Return -1 if no data */ static int portman_read_midi(struct portman *pm, int port) { unsigned char midi_data = 0; unsigned char cmdout; /* Saved address+IE bit. */ /* Make sure clocking edge is down before starting... */ portman_write_data(pm, 0); /* Make sure edge is down. */ /* Set destination address to PCP. */ cmdout = (port << 1) | INT_EN; /* Address + IE + No Strobe. */ portman_write_command(pm, cmdout); while ((portman_read_status(pm) & ESTB) == ESTB) cpu_relax(); /* Wait for strobe echo. */ /* After the address lines settle, check multiplexed RxAvail signal. * If data is available, read it. */ if ((portman_read_status(pm) & RXAVAIL) == 0) return -1; /* No data. */ /* Set the Strobe signal to enable the Rx clocking circuitry. */ portman_write_command(pm, cmdout | STROBE); /* Write address+IE+Strobe. */ while ((portman_read_status(pm) & ESTB) == 0) cpu_relax(); /* Wait for strobe echo. */ /* The first data bit (msb) is already sitting on the input line. */ midi_data = (portman_read_status(pm) & 128); portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ /* Data bit 6. */ portman_write_data(pm, 0); /* Cause falling edge while data settles. */ midi_data |= (portman_read_status(pm) >> 1) & 64; portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ /* Data bit 5. */ portman_write_data(pm, 0); /* Cause falling edge while data settles. */ midi_data |= (portman_read_status(pm) >> 2) & 32; portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ /* Data bit 4. */ portman_write_data(pm, 0); /* Cause falling edge while data settles. */ midi_data |= (portman_read_status(pm) >> 3) & 16; portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ /* Data bit 3. */ portman_write_data(pm, 0); /* Cause falling edge while data settles. */ midi_data |= (portman_read_status(pm) >> 4) & 8; portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ /* Data bit 2. */ portman_write_data(pm, 0); /* Cause falling edge while data settles. */ midi_data |= (portman_read_status(pm) >> 5) & 4; portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ /* Data bit 1. */ portman_write_data(pm, 0); /* Cause falling edge while data settles. */ midi_data |= (portman_read_status(pm) >> 6) & 2; portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ /* Data bit 0. */ portman_write_data(pm, 0); /* Cause falling edge while data settles. */ midi_data |= (portman_read_status(pm) >> 7) & 1; portman_write_data(pm, 1); /* Cause rising edge, which shifts data. */ portman_write_data(pm, 0); /* Return data clock low. */ /* De-assert Strobe and return data. */ portman_write_command(pm, cmdout); /* Output saved address+IE. */ /* Wait for strobe echo. */ while ((portman_read_status(pm) & ESTB) == ESTB) cpu_relax(); return (midi_data & 255); /* Shift back and return value. */ } /* * Checks if any input data on the given channel is available * Checks RxAvail */ static int portman_data_avail(struct portman *pm, int channel) { int command = INT_EN; switch (channel) { case 0: command |= RXDATA0; break; case 1: command |= RXDATA1; break; } /* Write hardware (assumme STROBE=0) */ portman_write_command(pm, command); /* Check multiplexed RxAvail signal */ if ((portman_read_status(pm) & RXAVAIL) == RXAVAIL) return 1; /* Data available */ /* No Data available */ return 0; } /* * Flushes any input */ static void portman_flush_input(struct portman *pm, unsigned char port) { /* Local variable for counting things */ unsigned int i = 0; unsigned char command = 0; switch (port) { case 0: command = RXDATA0; break; case 1: command = RXDATA1; break; default: snd_printk(KERN_WARNING "portman_flush_input() Won't flush port %i\n", port); return; } /* Set address for specified channel in port and allow to settle. */ portman_write_command(pm, command); /* Assert the Strobe and wait for echo back. */ portman_write_command(pm, command | STROBE); /* Wait for ESTB */ while ((portman_read_status(pm) & ESTB) == 0) cpu_relax(); /* Output clock cycles to the Rx circuitry. */ portman_write_data(pm, 0); /* Flush 250 bits... */ for (i = 0; i < 250; i++) { portman_write_data(pm, 1); portman_write_data(pm, 0); } /* Deassert the Strobe signal of the port and wait for it to settle. */ portman_write_command(pm, command | INT_EN); /* Wait for settling */ while ((portman_read_status(pm) & ESTB) == ESTB) cpu_relax(); } static int portman_probe(struct parport *p) { /* Initialize the parallel port data register. Will set Rx clocks * low in case we happen to be addressing the Rx ports at this time. */ /* 1 */ parport_write_data(p, 0); /* Initialize the parallel port command register, thus initializing * hardware handshake lines to midi box: * * Strobe = 0 * Interrupt Enable = 0 */ /* 2 */ parport_write_control(p, 0); /* Check if Portman PC/P 2x4 is out there. */ /* 3 */ parport_write_control(p, RXDATA0); /* Write Strobe=0 to command reg. */ /* Check for ESTB to be clear */ /* 4 */ if ((parport_read_status(p) & ESTB) == ESTB) return 1; /* CODE 1 - Strobe Failure. */ /* Set for RXDATA0 where no damage will be done. */ /* 5 */ parport_write_control(p, RXDATA0 + STROBE); /* Write Strobe=1 to command reg. */ /* 6 */ if ((parport_read_status(p) & ESTB) != ESTB) return 1; /* CODE 1 - Strobe Failure. */ /* 7 */ parport_write_control(p, 0); /* Reset Strobe=0. */ /* Check if Tx circuitry is functioning properly. If initialized * unit TxEmpty is false, send out char and see if if goes true. */ /* 8 */ parport_write_control(p, TXDATA0); /* Tx channel 0, strobe off. */ /* If PCP channel's TxEmpty is set (TxEmpty is read through the PP * Status Register), then go write data. Else go back and wait. */ /* 9 */ if ((parport_read_status(p) & TXEMPTY) == 0) return 2; /* Return OK status. */ return 0; } static int portman_device_init(struct portman *pm) { portman_flush_input(pm, 0); portman_flush_input(pm, 1); return 0; } /********************************************************************* * Rawmidi *********************************************************************/ static int snd_portman_midi_open(struct snd_rawmidi_substream *substream) { return 0; } static int snd_portman_midi_close(struct snd_rawmidi_substream *substream) { return 0; } static void snd_portman_midi_input_trigger(struct snd_rawmidi_substream *substream, int up) { struct portman *pm = substream->rmidi->private_data; unsigned long flags; spin_lock_irqsave(&pm->reg_lock, flags); if (up) pm->mode[substream->number] |= PORTMAN2X4_MODE_INPUT_TRIGGERED; else pm->mode[substream->number] &= ~PORTMAN2X4_MODE_INPUT_TRIGGERED; spin_unlock_irqrestore(&pm->reg_lock, flags); } static void snd_portman_midi_output_trigger(struct snd_rawmidi_substream *substream, int up) { struct portman *pm = substream->rmidi->private_data; unsigned long flags; unsigned char byte; spin_lock_irqsave(&pm->reg_lock, flags); if (up) { while ((snd_rawmidi_transmit(substream, &byte, 1) == 1)) portman_write_midi(pm, substream->number, byte); } spin_unlock_irqrestore(&pm->reg_lock, flags); } static struct snd_rawmidi_ops snd_portman_midi_output = { .open = snd_portman_midi_open, .close = snd_portman_midi_close, .trigger = snd_portman_midi_output_trigger, }; static struct snd_rawmidi_ops snd_portman_midi_input = { .open = snd_portman_midi_open, .close = snd_portman_midi_close, .trigger = snd_portman_midi_input_trigger, }; /* Create and initialize the rawmidi component */ static int __devinit snd_portman_rawmidi_create(struct snd_card *card) { struct portman *pm = card->private_data; struct snd_rawmidi *rmidi; struct snd_rawmidi_substream *substream; int err; err = snd_rawmidi_new(card, CARD_NAME, 0, PORTMAN_NUM_OUTPUT_PORTS, PORTMAN_NUM_INPUT_PORTS, &rmidi); if (err < 0) return err; rmidi->private_data = pm; strcpy(rmidi->name, CARD_NAME); rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT | SNDRV_RAWMIDI_INFO_INPUT | SNDRV_RAWMIDI_INFO_DUPLEX; pm->rmidi = rmidi; /* register rawmidi ops */ snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &snd_portman_midi_output); snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &snd_portman_midi_input); /* name substreams */ /* output */ list_for_each_entry(substream, &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams, list) { sprintf(substream->name, "Portman2x4 %d", substream->number+1); } /* input */ list_for_each_entry(substream, &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams, list) { pm->midi_input[substream->number] = substream; sprintf(substream->name, "Portman2x4 %d", substream->number+1); } return err; } /********************************************************************* * parport stuff *********************************************************************/ static void snd_portman_interrupt(void *userdata) { unsigned char midivalue = 0; struct portman *pm = ((struct snd_card*)userdata)->private_data; spin_lock(&pm->reg_lock); /* While any input data is waiting */ while ((portman_read_status(pm) & INT_REQ) == INT_REQ) { /* If data available on channel 0, read it and stuff it into the queue. */ if (portman_data_avail(pm, 0)) { /* Read Midi */ midivalue = portman_read_midi(pm, 0); /* put midi into queue... */ if (pm->mode[0] & PORTMAN2X4_MODE_INPUT_TRIGGERED) snd_rawmidi_receive(pm->midi_input[0], &midivalue, 1); } /* If data available on channel 1, read it and stuff it into the queue. */ if (portman_data_avail(pm, 1)) { /* Read Midi */ midivalue = portman_read_midi(pm, 1); /* put midi into queue... */ if (pm->mode[1] & PORTMAN2X4_MODE_INPUT_TRIGGERED) snd_rawmidi_receive(pm->midi_input[1], &midivalue, 1); } } spin_unlock(&pm->reg_lock); } static int __devinit snd_portman_probe_port(struct parport *p) { struct pardevice *pardev; int res; pardev = parport_register_device(p, DRIVER_NAME, NULL, NULL, NULL, 0, NULL); if (!pardev) return -EIO; if (parport_claim(pardev)) { parport_unregister_device(pardev); return -EIO; } res = portman_probe(p); parport_release(pardev); parport_unregister_device(pardev); return res ? -EIO : 0; } static void __devinit snd_portman_attach(struct parport *p) { struct platform_device *device; device = platform_device_alloc(PLATFORM_DRIVER, device_count); if (!device) return; /* Temporary assignment to forward the parport */ platform_set_drvdata(device, p); if (platform_device_add(device) < 0) { platform_device_put(device); return; } /* Since we dont get the return value of probe * We need to check if device probing succeeded or not */ if (!platform_get_drvdata(device)) { platform_device_unregister(device); return; } /* register device in global table */ platform_devices[device_count] = device; device_count++; } static void snd_portman_detach(struct parport *p) { /* nothing to do here */ } static struct parport_driver portman_parport_driver = { .name = "portman2x4", .attach = snd_portman_attach, .detach = snd_portman_detach }; /********************************************************************* * platform stuff *********************************************************************/ static void snd_portman_card_private_free(struct snd_card *card) { struct portman *pm = card->private_data; struct pardevice *pardev = pm->pardev; if (pardev) { if (pm->pardev_claimed) parport_release(pardev); parport_unregister_device(pardev); } portman_free(pm); } static int __devinit snd_portman_probe(struct platform_device *pdev) { struct pardevice *pardev; struct parport *p; int dev = pdev->id; struct snd_card *card = NULL; struct portman *pm = NULL; int err; p = platform_get_drvdata(pdev); platform_set_drvdata(pdev, NULL); if (dev >= SNDRV_CARDS) return -ENODEV; if (!enable[dev]) return -ENOENT; if ((err = snd_portman_probe_port(p)) < 0) return err; err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &card); if (err < 0) { snd_printd("Cannot create card\n"); return err; } strcpy(card->driver, DRIVER_NAME); strcpy(card->shortname, CARD_NAME); sprintf(card->longname, "%s at 0x%lx, irq %i", card->shortname, p->base, p->irq); pardev = parport_register_device(p, /* port */ DRIVER_NAME, /* name */ NULL, /* preempt */ NULL, /* wakeup */ snd_portman_interrupt, /* ISR */ PARPORT_DEV_EXCL, /* flags */ (void *)card); /* private */ if (pardev == NULL) { snd_printd("Cannot register pardevice\n"); err = -EIO; goto __err; } if ((err = portman_create(card, pardev, &pm)) < 0) { snd_printd("Cannot create main component\n"); parport_unregister_device(pardev); goto __err; } card->private_data = pm; card->private_free = snd_portman_card_private_free; if ((err = snd_portman_rawmidi_create(card)) < 0) { snd_printd("Creating Rawmidi component failed\n"); goto __err; } /* claim parport */ if (parport_claim(pardev)) { snd_printd("Cannot claim parport 0x%lx\n", pardev->port->base); err = -EIO; goto __err; } pm->pardev_claimed = 1; /* init device */ if ((err = portman_device_init(pm)) < 0) goto __err; platform_set_drvdata(pdev, card); snd_card_set_dev(card, &pdev->dev); /* At this point card will be usable */ if ((err = snd_card_register(card)) < 0) { snd_printd("Cannot register card\n"); goto __err; } snd_printk(KERN_INFO "Portman 2x4 on 0x%lx\n", p->base); return 0; __err: snd_card_free(card); return err; } static int __devexit snd_portman_remove(struct platform_device *pdev) { struct snd_card *card = platform_get_drvdata(pdev); if (card) snd_card_free(card); return 0; } static struct platform_driver snd_portman_driver = { .probe = snd_portman_probe, .remove = __devexit_p(snd_portman_remove), .driver = { .name = PLATFORM_DRIVER } }; /********************************************************************* * module init stuff *********************************************************************/ static void snd_portman_unregister_all(void) { int i; for (i = 0; i < SNDRV_CARDS; ++i) { if (platform_devices[i]) { platform_device_unregister(platform_devices[i]); platform_devices[i] = NULL; } } platform_driver_unregister(&snd_portman_driver); parport_unregister_driver(&portman_parport_driver); } static int __init snd_portman_module_init(void) { int err; if ((err = platform_driver_register(&snd_portman_driver)) < 0) return err; if (parport_register_driver(&portman_parport_driver) != 0) { platform_driver_unregister(&snd_portman_driver); return -EIO; } if (device_count == 0) { snd_portman_unregister_all(); return -ENODEV; } return 0; } static void __exit snd_portman_module_exit(void) { snd_portman_unregister_all(); } module_init(snd_portman_module_init); module_exit(snd_portman_module_exit);