HID: Prodikeys PC-MIDI HID Driver

A specialised HID driver for the Creative Prodikeys PC-MIDI USB Keyboard.

The Prodikeys PC-MIDI is a multifunction keyboard comprising a qwerty keyboard,
multimedia keys and a touch sensitive musical keyboard.

The specialised HID driver adds full support for the musical keyboard and extra
multimedia keys which are not currently handled by the default HID driver.

The specialised HID driver interfaces with ALSA, and presents the midi keyboard
as a rawmidi device. Sustain duration, octave shifting and the midi output
channel can be read/written form userspace via sysfs.
Signed-off-by: Don Prince <dhprince-devel@yahoo.co.uk>
ALSA parts:
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Documentation/ABI/testing/sysfs-driver-hid-prodikeys

+What:		/sys/bus/hid/drivers/prodikeys/.../channel
+Date:		April 2010
+KernelVersion:	2.6.34
+Contact:	Don Prince <dhprince.devel@yahoo.co.uk>
+Description:
+		Allows control (via software) the midi channel to which
+		that the pc-midi keyboard will output.midi data.
+		Range: 0..15
+		Type:  Read/write
+What:		/sys/bus/hid/drivers/prodikeys/.../sustain
+Date:		April 2010
+KernelVersion:	2.6.34
+Contact:	Don Prince <dhprince.devel@yahoo.co.uk>
+Description:
+		Allows control (via software) the sustain duration of a
+		note held by the pc-midi driver.
+		0 means sustain mode is disabled.
+		Range: 0..5000 (milliseconds)
+		Type:  Read/write
+What:		/sys/bus/hid/drivers/prodikeys/.../octave
+Date:		April 2010
+KernelVersion:	2.6.34
+Contact:	Don Prince <dhprince.devel@yahoo.co.uk>
+Description:
+		Controls the octave shift modifier in the pc-midi driver.
+		The octave can be shifted via software up/down 2 octaves.
+		0 means the no ocatve shift.
+		Range: -2..2 (minus 2 to plus 2)
+		Type: Read/Write

drivers/hid/Kconfig

@@ -100,6 +100,22 @@ config HID_CHICONY
 	---help---
 	Support for Chicony Tactical pad.
 
+config HID_PRODIKEYS
+	tristate "Prodikeys PC-MIDI Keyboard support" if EMBEDDED
+	depends on USB_HID && SND
+	select SND_RAWMIDI
+	default !EMBEDDED
+	---help---
+	Support for Prodikeys PC-MIDI Keyboard device support.
+	Say Y here to enable support for this device.
+	- Prodikeys PC-MIDI keyboard.
+	  The Prodikeys PC-MIDI acts as a USB Audio device, with one MIDI
+	  input and one MIDI output. These MIDI jacks appear as
+	  a sound "card" in the ALSA sound system.
+	  Note: if you say N here, this device will still function as a basic
+	  multimedia keyboard, but will lack support for the musical keyboard
+	  and some additional multimedia keys.
+
 config HID_CYPRESS
 	tristate "Cypress" if EMBEDDED
 	depends on USB_HID

drivers/hid/Makefile

@@ -41,6 +41,7 @@ obj-$(CONFIG_HID_MONTEREY)	+= hid-monterey.o
 obj-$(CONFIG_HID_MOSART)	+= hid-mosart.o
 obj-$(CONFIG_HID_NTRIG)		+= hid-ntrig.o
 obj-$(CONFIG_HID_ORTEK)		+= hid-ortek.o
+obj-$(CONFIG_HID_PRODIKEYS)	+= hid-prodikeys.o
 obj-$(CONFIG_HID_QUANTA)	+= hid-quanta.o
 obj-$(CONFIG_HID_PANTHERLORD)	+= hid-pl.o
 obj-$(CONFIG_HID_PETALYNX)	+= hid-petalynx.o

drivers/hid/hid-core.c

@@ -1293,6 +1293,7 @@ static const struct hid_device_id hid_blacklist[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHERRY, USB_DEVICE_ID_CHERRY_CYMOTION) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHERRY, USB_DEVICE_ID_CHERRY_CYMOTION_SOLAR) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_TACTICAL_PAD) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_CREATIVELABS, USB_DEVICE_ID_PRODIKEYS_PCMIDI) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, USB_DEVICE_ID_CYPRESS_BARCODE_1) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, USB_DEVICE_ID_CYPRESS_BARCODE_2) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, USB_DEVICE_ID_CYPRESS_BARCODE_3) },

drivers/hid/hid-ids.h

@@ -148,6 +148,9 @@
 #define USB_DEVICE_ID_CODEMERCS_IOW_FIRST	0x1500
 #define USB_DEVICE_ID_CODEMERCS_IOW_LAST	0x15ff
 
+#define USB_VENDOR_ID_CREATIVELABS	0x041e
+#define USB_DEVICE_ID_PRODIKEYS_PCMIDI	0x2801
+
 #define USB_VENDOR_ID_CYGNAL		0x10c4
 #define USB_DEVICE_ID_CYGNAL_RADIO_SI470X	0x818a
 

drivers/hid/hid-prodikeys.c

+/*
+ *  HID driver for the Prodikeys PC-MIDI Keyboard
+ *  providing midi & extra multimedia keys functionality
+ *
+ *  Copyright (c) 2009 Don Prince <dhprince.devel@yahoo.co.uk>
+ *
+ *  Controls for Octave Shift Up/Down, Channel, and
+ *  Sustain Duration available via sysfs.
+ *
+ */
+
+/*
+ * 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.
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/mutex.h>
+#include <linux/hid.h>
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/rawmidi.h>
+#include "usbhid/usbhid.h"
+#include "hid-ids.h"
+
+
+#define pk_debug(format, arg...) \
+	pr_debug("hid-prodikeys: " format "\n" , ## arg)
+#define pk_error(format, arg...) \
+	pr_err("hid-prodikeys: " format "\n" , ## arg)
+
+struct pcmidi_snd;
+
+struct pk_device {
+	unsigned long		quirks;
+
+	struct hid_device	*hdev;
+	struct pcmidi_snd	*pm; /* pcmidi device context */
+};
+
+struct pcmidi_snd;
+
+struct pcmidi_sustain {
+	unsigned long		in_use;
+	struct pcmidi_snd	*pm;
+	struct timer_list	timer;
+	unsigned char		status;
+	unsigned char		note;
+	unsigned char		velocity;
+};
+
+#define PCMIDI_SUSTAINED_MAX	32
+struct pcmidi_snd {
+	struct pk_device		*pk;
+	unsigned short			ifnum;
+	struct hid_report		*pcmidi_report6;
+	struct input_dev		*input_ep82;
+	unsigned short			midi_mode;
+	unsigned short			midi_sustain_mode;
+	unsigned short			midi_sustain;
+	unsigned short			midi_channel;
+	short				midi_octave;
+	struct pcmidi_sustain		sustained_notes[PCMIDI_SUSTAINED_MAX];
+	unsigned short			fn_state;
+	unsigned short			last_key[24];
+	spinlock_t			rawmidi_in_lock;
+	struct snd_card			*card;
+	struct snd_rawmidi		*rwmidi;
+	struct snd_rawmidi_substream	*in_substream;
+	struct snd_rawmidi_substream	*out_substream;
+	unsigned long			in_triggered;
+	unsigned long			out_active;
+};
+
+#define PK_QUIRK_NOGET	0x00010000
+#define PCMIDI_MIDDLE_C 60
+#define PCMIDI_CHANNEL_MIN 0
+#define PCMIDI_CHANNEL_MAX 15
+#define PCMIDI_OCTAVE_MIN (-2)
+#define PCMIDI_OCTAVE_MAX 2
+#define PCMIDI_SUSTAIN_MIN 0
+#define PCMIDI_SUSTAIN_MAX 5000
+
+static const char shortname[] = "PC-MIDI";
+static const char longname[] = "Prodikeys PC-MIDI Keyboard";
+
+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;
+
+module_param_array(index, int, NULL, 0444);
+module_param_array(id, charp, NULL, 0444);
+module_param_array(enable, bool, NULL, 0444);
+MODULE_PARM_DESC(index, "Index value for the PC-MIDI virtual audio driver");
+MODULE_PARM_DESC(id, "ID string for the PC-MIDI virtual audio driver");
+MODULE_PARM_DESC(enable, "Enable for the PC-MIDI virtual audio driver");
+
+
+/* Output routine for the sysfs channel file */
+static ssize_t show_channel(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+
+	dbg_hid("pcmidi sysfs read channel=%u\n", pk->pm->midi_channel);
+
+	return sprintf(buf, "%u (min:%u, max:%u)\n", pk->pm->midi_channel,
+		PCMIDI_CHANNEL_MIN, PCMIDI_CHANNEL_MAX);
+}
+
+/* Input routine for the sysfs channel file */
+static ssize_t store_channel(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+
+	unsigned channel = 0;
+
+	if (sscanf(buf, "%u", &channel) > 0 && channel <= PCMIDI_CHANNEL_MAX) {
+		dbg_hid("pcmidi sysfs write channel=%u\n", channel);
+		pk->pm->midi_channel = channel;
+		return strlen(buf);
+	}
+	return -EINVAL;
+}
+
+static DEVICE_ATTR(channel, S_IRUGO | S_IWUGO, show_channel,
+		store_channel);
+
+static struct device_attribute *sysfs_device_attr_channel = {
+		&dev_attr_channel,
+		};
+
+/* Output routine for the sysfs sustain file */
+static ssize_t show_sustain(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+
+	dbg_hid("pcmidi sysfs read sustain=%u\n", pk->pm->midi_sustain);
+
+	return sprintf(buf, "%u (off:%u, max:%u (ms))\n", pk->pm->midi_sustain,
+		PCMIDI_SUSTAIN_MIN, PCMIDI_SUSTAIN_MAX);
+}
+
+/* Input routine for the sysfs sustain file */
+static ssize_t store_sustain(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+
+	unsigned sustain = 0;
+
+	if (sscanf(buf, "%u", &sustain) > 0 && sustain <= PCMIDI_SUSTAIN_MAX) {
+		dbg_hid("pcmidi sysfs write sustain=%u\n", sustain);
+		pk->pm->midi_sustain = sustain;
+		pk->pm->midi_sustain_mode =
+			(0 == sustain || !pk->pm->midi_mode) ? 0 : 1;
+		return strlen(buf);
+	}
+	return -EINVAL;
+}
+
+static DEVICE_ATTR(sustain, S_IRUGO | S_IWUGO, show_sustain,
+		store_sustain);
+
+static struct device_attribute *sysfs_device_attr_sustain = {
+		&dev_attr_sustain,
+		};
+
+/* Output routine for the sysfs octave file */
+static ssize_t show_octave(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+
+	dbg_hid("pcmidi sysfs read octave=%d\n", pk->pm->midi_octave);
+
+	return sprintf(buf, "%d (min:%d, max:%d)\n", pk->pm->midi_octave,
+		PCMIDI_OCTAVE_MIN, PCMIDI_OCTAVE_MAX);
+}
+
+/* Input routine for the sysfs octave file */
+static ssize_t store_octave(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+
+	int octave = 0;
+
+	if (sscanf(buf, "%d", &octave) > 0 &&
+		octave >= PCMIDI_OCTAVE_MIN && octave <= PCMIDI_OCTAVE_MAX) {
+		dbg_hid("pcmidi sysfs write octave=%d\n", octave);
+		pk->pm->midi_octave = octave;
+		return strlen(buf);
+	}
+	return -EINVAL;
+}
+
+static DEVICE_ATTR(octave, S_IRUGO | S_IWUGO, show_octave,
+		store_octave);
+
+static struct device_attribute *sysfs_device_attr_octave = {
+		&dev_attr_octave,
+		};
+
+
+static void pcmidi_send_note(struct pcmidi_snd *pm,
+	unsigned char status, unsigned char note, unsigned char velocity)
+{
+	unsigned long flags;
+	unsigned char buffer[3];
+
+	buffer[0] = status;
+	buffer[1] = note;
+	buffer[2] = velocity;
+
+	spin_lock_irqsave(&pm->rawmidi_in_lock, flags);
+
+	if (!pm->in_substream)
+		goto drop_note;
+	if (!test_bit(pm->in_substream->number, &pm->in_triggered))
+		goto drop_note;
+
+	snd_rawmidi_receive(pm->in_substream, buffer, 3);
+
+drop_note:
+	spin_unlock_irqrestore(&pm->rawmidi_in_lock, flags);
+
+	return;
+}
+
+void pcmidi_sustained_note_release(unsigned long data)
+{
+	struct pcmidi_sustain *pms = (struct pcmidi_sustain *)data;
+
+	pcmidi_send_note(pms->pm, pms->status, pms->note, pms->velocity);
+	pms->in_use = 0;
+}
+
+void init_sustain_timers(struct pcmidi_snd *pm)
+{
+	struct pcmidi_sustain *pms;
+	unsigned i;
+
+	for (i = 0; i < PCMIDI_SUSTAINED_MAX; i++) {
+		pms = &pm->sustained_notes[i];
+		pms->in_use = 0;
+		pms->pm = pm;
+		setup_timer(&pms->timer, pcmidi_sustained_note_release,
+			(unsigned long)pms);
+	}
+}
+
+void stop_sustain_timers(struct pcmidi_snd *pm)
+{
+	struct pcmidi_sustain *pms;
+	unsigned i;
+
+	for (i = 0; i < PCMIDI_SUSTAINED_MAX; i++) {
+		pms = &pm->sustained_notes[i];
+		pms->in_use = 1;
+		del_timer_sync(&pms->timer);
+	}
+}
+
+static int pcmidi_get_output_report(struct pcmidi_snd *pm)
+{
+	struct hid_device *hdev = pm->pk->hdev;
+	struct hid_report *report;
+
+	list_for_each_entry(report,
+		&hdev->report_enum[HID_OUTPUT_REPORT].report_list, list) {
+		if (!(6 == report->id))
+			continue;
+
+		if (report->maxfield < 1) {
+			dev_err(&hdev->dev, "output report is empty\n");
+			break;
+		}
+		if (report->field[0]->report_count != 2) {
+			dev_err(&hdev->dev, "field count too low\n");
+			break;
+		}
+		pm->pcmidi_report6 = report;
+		return 0;
+	}
+	/* should never get here */
+	return -ENODEV;
+}
+
+static void pcmidi_submit_output_report(struct pcmidi_snd *pm, int state)
+{
+	struct hid_device *hdev = pm->pk->hdev;
+	struct hid_report *report = pm->pcmidi_report6;
+	report->field[0]->value[0] = 0x01;
+	report->field[0]->value[1] = state;
+
+	usbhid_submit_report(hdev, report, USB_DIR_OUT);
+}
+
+static int pcmidi_handle_report1(struct pcmidi_snd *pm, u8 *data)
+{
+	u32 bit_mask;
+
+	bit_mask = data[1];
+	bit_mask = (bit_mask << 8) | data[2];
+	bit_mask = (bit_mask << 8) | data[3];
+
+	dbg_hid("pcmidi mode: %d\n", pm->midi_mode);
+
+	/*KEY_MAIL or octave down*/
+	if (pm->midi_mode && bit_mask == 0x004000) {
+		/* octave down */
+		pm->midi_octave--;
+		if (pm->midi_octave < -2)
+			pm->midi_octave = -2;
+		dbg_hid("pcmidi mode: %d octave: %d\n",
+			pm->midi_mode, pm->midi_octave);
+		return 1;
+	}
+	/*KEY_WWW or sustain*/
+	else if (pm->midi_mode && bit_mask == 0x000004) {
+		/* sustain on/off*/
+		pm->midi_sustain_mode ^= 0x1;
+		return 1;
+	}
+
+	return 0; /* continue key processing */
+}
+
+static int pcmidi_handle_report3(struct pcmidi_snd *pm, u8 *data, int size)
+{
+	struct pcmidi_sustain *pms;
+	unsigned i, j;
+	unsigned char status, note, velocity;
+
+	unsigned num_notes = (size-1)/2;
+	for (j = 0; j < num_notes; j++)	{
+		note = data[j*2+1];
+		velocity = data[j*2+2];
+
+		if (note < 0x81) { /* note on */
+			status = 128 + 16 + pm->midi_channel; /* 1001nnnn */
+			note = note - 0x54 + PCMIDI_MIDDLE_C +
+				(pm->midi_octave * 12);
+			if (0 == velocity)
+				velocity = 1; /* force note on */
+		} else { /* note off */
+			status = 128 + pm->midi_channel; /* 1000nnnn */
+			note = note - 0x94 + PCMIDI_MIDDLE_C +
+				(pm->midi_octave*12);
+
+			if (pm->midi_sustain_mode) {
+				for (i = 0; i < PCMIDI_SUSTAINED_MAX; i++) {
+					pms = &pm->sustained_notes[i];
+					if (!pms->in_use) {
+						pms->status = status;
+						pms->note = note;
+						pms->velocity = velocity;
+						pms->in_use = 1;
+
+						mod_timer(&pms->timer,
+							jiffies +
+					msecs_to_jiffies(pm->midi_sustain));
+						return 1;
+					}
+				}
+			}
+		}
+		pcmidi_send_note(pm, status, note, velocity);
+	}
+
+	return 1;
+}
+
+static int pcmidi_handle_report4(struct pcmidi_snd *pm, u8 *data)
+{
+	unsigned	key;
+	u32		bit_mask;
+	u32		bit_index;
+
+	bit_mask = data[1];
+	bit_mask = (bit_mask << 8) | data[2];
+	bit_mask = (bit_mask << 8) | data[3];
+
+	/* break keys */
+	for (bit_index = 0; bit_index < 24; bit_index++) {
+		key = pm->last_key[bit_index];
+		if (!((0x01 << bit_index) & bit_mask)) {
+			input_event(pm->input_ep82, EV_KEY,
+				pm->last_key[bit_index], 0);
+				pm->last_key[bit_index] = 0;
+		}
+	}
+
+	/* make keys */
+	for (bit_index = 0; bit_index < 24; bit_index++) {
+		key = 0;
+		switch ((0x01 << bit_index) & bit_mask) {
+		case 0x000010: /* Fn lock*/
+			pm->fn_state ^= 0x000010;
+			if (pm->fn_state)
+				pcmidi_submit_output_report(pm, 0xc5);
+			else
+				pcmidi_submit_output_report(pm, 0xc6);
+			continue;
+		case 0x020000: /* midi launcher..send a key (qwerty) or not? */
+			pcmidi_submit_output_report(pm, 0xc1);
+			pm->midi_mode ^= 0x01;
+
+			dbg_hid("pcmidi mode: %d\n", pm->midi_mode);
+			continue;
+		case 0x100000: /* KEY_MESSENGER or octave up */
+			dbg_hid("pcmidi mode: %d\n", pm->midi_mode);
+			if (pm->midi_mode) {
+				pm->midi_octave++;
+				if (pm->midi_octave > 2)
+					pm->midi_octave = 2;
+				dbg_hid("pcmidi mode: %d octave: %d\n",
+					pm->midi_mode, pm->midi_octave);
+			    continue;
+			} else
+				key = KEY_MESSENGER;
+			break;
+		case 0x400000:
+			key = KEY_CALENDAR;
+			break;
+		case 0x080000:
+			key = KEY_ADDRESSBOOK;
+			break;
+		case 0x040000:
+			key = KEY_DOCUMENTS;
+			break;
+		case 0x800000:
+			key = KEY_WORDPROCESSOR;
+			break;
+		case 0x200000:
+			key = KEY_SPREADSHEET;
+			break;
+		case 0x010000:
+			key = KEY_COFFEE;
+			break;
+		case 0x000100:
+			key = KEY_HELP;
+			break;
+		case 0x000200:
+			key = KEY_SEND;
+			break;
+		case 0x000400:
+			key = KEY_REPLY;
+			break;
+		case 0x000800:
+			key = KEY_FORWARDMAIL;
+			break;
+		case 0x001000:
+			key = KEY_NEW;
+			break;
+		case 0x002000:
+			key = KEY_OPEN;
+			break;
+		case 0x004000:
+			key = KEY_CLOSE;
+			break;
+		case 0x008000:
+			key = KEY_SAVE;
+			break;
+		case 0x000001:
+			key = KEY_UNDO;
+			break;
+		case 0x000002:
+			key = KEY_REDO;
+			break;
+		case 0x000004:
+			key = KEY_SPELLCHECK;
+			break;
+		case 0x000008:
+			key = KEY_PRINT;
+			break;
+		}
+		if (key) {
+			input_event(pm->input_ep82, EV_KEY, key, 1);
+			pm->last_key[bit_index] = key;
+		}
+	}
+
+	return 1;
+}
+
+int pcmidi_handle_report(
+	struct pcmidi_snd *pm, unsigned report_id, u8 *data, int size)
+{
+	int ret = 0;
+
+	switch (report_id) {
+	case 0x01: /* midi keys (qwerty)*/
+		ret = pcmidi_handle_report1(pm, data);
+		break;
+	case 0x03: /* midi keyboard (musical)*/
+		ret = pcmidi_handle_report3(pm, data, size);
+		break;
+	case 0x04: /* multimedia/midi keys (qwerty)*/
+		ret = pcmidi_handle_report4(pm, data);
+		break;
+	}
+	return ret;
+}
+
+void pcmidi_setup_extra_keys(struct pcmidi_snd *pm, struct input_dev *input)
+{
+	/* reassigned functionality for N/A keys
+		MY PICTURES =>	KEY_WORDPROCESSOR
+		MY MUSIC=>	KEY_SPREADSHEET
+	*/
+	unsigned int keys[] = {
+		KEY_FN,
+		KEY_MESSENGER, KEY_CALENDAR,
+		KEY_ADDRESSBOOK, KEY_DOCUMENTS,
+		KEY_WORDPROCESSOR,
+		KEY_SPREADSHEET,
+		KEY_COFFEE,
+		KEY_HELP, KEY_SEND,
+		KEY_REPLY, KEY_FORWARDMAIL,
+		KEY_NEW, KEY_OPEN,
+		KEY_CLOSE, KEY_SAVE,
+		KEY_UNDO, KEY_REDO,
+		KEY_SPELLCHECK,	KEY_PRINT,
+		0
+	};
+
+	unsigned int *pkeys = &keys[0];
+	unsigned short i;
+
+	if (pm->ifnum != 1)  /* only set up ONCE for interace 1 */
+		return;
+
+	pm->input_ep82 = input;
+
+	for (i = 0; i < 24; i++)
+		pm->last_key[i] = 0;
+
+	while (*pkeys != 0) {
+		set_bit(*pkeys, pm->input_ep82->keybit);
+		++pkeys;
+	}
+}
+
+static int pcmidi_set_operational(struct pcmidi_snd *pm)
+{
+	if (pm->ifnum != 1)
+		return 0; /* only set up ONCE for interace 1 */
+
+	pcmidi_get_output_report(pm);
+	pcmidi_submit_output_report(pm, 0xc1);
+	return 0;
+}
+
+static int pcmidi_snd_free(struct snd_device *dev)
+{
+	return 0;
+}
+
+static int pcmidi_in_open(struct snd_rawmidi_substream *substream)
+{
+	struct pcmidi_snd *pm = substream->rmidi->private_data;
+
+	dbg_hid("pcmidi in open\n");
+	pm->in_substream = substream;
+	return 0;
+}
+
+static int pcmidi_in_close(struct snd_rawmidi_substream *substream)
+{
+	dbg_hid("pcmidi in close\n");
+	return 0;
+}
+
+static void pcmidi_in_trigger(struct snd_rawmidi_substream *substream, int up)
+{
+	struct pcmidi_snd *pm = substream->rmidi->private_data;
+
+	dbg_hid("pcmidi in trigger %d\n", up);
+
+	pm->in_triggered = up;
+}
+
+static struct snd_rawmidi_ops pcmidi_in_ops = {
+	.open = pcmidi_in_open,
+	.close = pcmidi_in_close,
+	.trigger = pcmidi_in_trigger
+};
+
+int pcmidi_snd_initialise(struct pcmidi_snd *pm)
+{
+	static int dev;
+	struct snd_card *card;
+	struct snd_rawmidi *rwmidi;
+	int err;
+
+	static struct snd_device_ops ops = {
+		.dev_free = pcmidi_snd_free,
+	};
+
+	if (pm->ifnum != 1)
+		return 0; /* only set up midi device ONCE for interace 1 */
+
+	if (dev >= SNDRV_CARDS)
+		return -ENODEV;
+
+	if (!enable[dev]) {
+		dev++;
+		return -ENOENT;
+	}
+
+	/* Setup sound card */
+
+	err = snd_card_create(index[dev], id[dev], THIS_MODULE, 0, &card);
+	if (err < 0) {
+		pk_error("failed to create pc-midi sound card\n");
+		err = -ENOMEM;
+		goto fail;
+	}
+	pm->card = card;
+
+	/* Setup sound device */
+	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, pm, &ops);
+	if (err < 0) {
+		pk_error("failed to create pc-midi sound device: error %d\n",
+			err);
+		goto fail;
+	}
+
+	strncpy(card->driver, shortname, sizeof(card->driver));
+	strncpy(card->shortname, shortname, sizeof(card->shortname));
+	strncpy(card->longname, longname, sizeof(card->longname));
+
+	/* Set up rawmidi */
+	err = snd_rawmidi_new(card, card->shortname, 0,
+			      0, 1, &rwmidi);
+	if (err < 0) {
+		pk_error("failed to create pc-midi rawmidi device: error %d\n",
+			err);
+		goto fail;
+	}
+	pm->rwmidi = rwmidi;
+	strncpy(rwmidi->name, card->shortname, sizeof(rwmidi->name));
+	rwmidi->info_flags = SNDRV_RAWMIDI_INFO_INPUT;
+	rwmidi->private_data = pm;
+
+	snd_rawmidi_set_ops(rwmidi, SNDRV_RAWMIDI_STREAM_INPUT,
+		&pcmidi_in_ops);
+
+	snd_card_set_dev(card, &pm->pk->hdev->dev);
+
+	/* create sysfs variables */
+	err = device_create_file(&pm->pk->hdev->dev,
+				 sysfs_device_attr_channel);
+	if (err < 0) {
+		pk_error("failed to create sysfs attribute channel: error %d\n",
+			err);
+		goto fail;
+	}
+
+	err = device_create_file(&pm->pk->hdev->dev,
+				sysfs_device_attr_sustain);
+	if (err < 0) {
+		pk_error("failed to create sysfs attribute sustain: error %d\n",
+			err);
+		goto fail_attr_sustain;
+	}
+
+	err = device_create_file(&pm->pk->hdev->dev,
+			 sysfs_device_attr_octave);
+	if (err < 0) {
+		pk_error("failed to create sysfs attribute octave: error %d\n",
+			err);
+		goto fail_attr_octave;
+	}
+
+	spin_lock_init(&pm->rawmidi_in_lock);
+
+	init_sustain_timers(pm);
+	pcmidi_set_operational(pm);
+
+	/* register it */
+	err = snd_card_register(card);
+	if (err < 0) {
+		pk_error("failed to register pc-midi sound card: error %d\n",
+			 err);
+			 goto fail_register;
+	}
+
+	dbg_hid("pcmidi_snd_initialise finished ok\n");
+	return 0;
+
+fail_register:
+	stop_sustain_timers(pm);
+	device_remove_file(&pm->pk->hdev->dev, sysfs_device_attr_octave);
+fail_attr_octave:
+	device_remove_file(&pm->pk->hdev->dev, sysfs_device_attr_sustain);
+fail_attr_sustain:
+	device_remove_file(&pm->pk->hdev->dev, sysfs_device_attr_channel);
+fail:
+	if (pm->card) {
+		snd_card_free(pm->card);
+		pm->card = NULL;
+	}
+	return err;
+}
+
+int pcmidi_snd_terminate(struct pcmidi_snd *pm)
+{
+	if (pm->card) {
+		stop_sustain_timers(pm);
+
+		device_remove_file(&pm->pk->hdev->dev,
+			sysfs_device_attr_channel);
+		device_remove_file(&pm->pk->hdev->dev,
+			sysfs_device_attr_sustain);
+		device_remove_file(&pm->pk->hdev->dev,
+			sysfs_device_attr_octave);
+
+		snd_card_disconnect(pm->card);
+		snd_card_free_when_closed(pm->card);
+	}
+
+	return 0;
+}
+
+/*
+ * PC-MIDI report descriptor for report id is wrong.
+ */
+static void pk_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+		unsigned int rsize)
+{
+	if (rsize == 178 &&
+	      rdesc[111] == 0x06 && rdesc[112] == 0x00 &&
+	      rdesc[113] == 0xff) {
+		dev_info(&hdev->dev, "fixing up pc-midi keyboard report "
+			"descriptor\n");
+
+		rdesc[144] = 0x18; /* report 4: was 0x10 report count */
+	}
+}
+
+static int pk_input_mapping(struct hid_device *hdev, struct hid_input *hi,
+		struct hid_field *field, struct hid_usage *usage,
+		unsigned long **bit, int *max)
+{
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+	struct pcmidi_snd *pm;
+
+	pm = pk->pm;
+
+	if (HID_UP_MSVENDOR == (usage->hid & HID_USAGE_PAGE) &&
+		1 == pm->ifnum) {
+		pcmidi_setup_extra_keys(pm, hi->input);
+		return 0;
+	}
+
+	return 0;
+}
+
+
+static int pk_raw_event(struct hid_device *hdev, struct hid_report *report,
+	u8 *data, int size)
+{
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+	int ret = 0;
+
+	if (1 == pk->pm->ifnum) {
+		if (report->id == data[0])
+			switch (report->id) {
+			case 0x01: /* midi keys (qwerty)*/
+			case 0x03: /* midi keyboard (musical)*/
+			case 0x04: /* extra/midi keys (qwerty)*/
+				ret = pcmidi_handle_report(pk->pm,
+						report->id, data, size);
+				break;
+			}
+	}
+
+	return ret;
+}
+
+static int pk_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	int ret;
+	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
+	unsigned short ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
+	unsigned long quirks = id->driver_data;
+	struct pk_device *pk;
+	struct pcmidi_snd *pm = NULL;
+
+	pk = kzalloc(sizeof(*pk), GFP_KERNEL);
+	if (pk == NULL) {
+		dev_err(&hdev->dev, "prodikeys: can't alloc descriptor\n");
+		return -ENOMEM;
+	}
+
+	pk->hdev = hdev;
+
+	pm = kzalloc(sizeof(*pm), GFP_KERNEL);
+	if (pm == NULL) {
+		dev_err(&hdev->dev,
+			"prodikeys: can't alloc descriptor\n");
+		ret = -ENOMEM;
+		goto err_free;
+	}
+
+	pm->pk = pk;
+	pk->pm = pm;
+	pm->ifnum = ifnum;
+
+	hid_set_drvdata(hdev, pk);
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		dev_err(&hdev->dev, "prodikeys: hid parse failed\n");
+		goto err_free;
+	}
+
+	if (quirks & PK_QUIRK_NOGET) { /* hid_parse cleared all the quirks */
+		hdev->quirks |= HID_QUIRK_NOGET;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+	if (ret) {
+		dev_err(&hdev->dev, "prodikeys: hw start failed\n");
+		goto err_free;
+	}
+
+	ret = pcmidi_snd_initialise(pm);
+	if (ret < 0)
+		goto err_stop;
+
+	return 0;
+err_stop:
+	hid_hw_stop(hdev);
+err_free:
+	if (pm != NULL)
+		kfree(pm);
+
+	kfree(pk);
+	return ret;
+}
+
+static void pk_remove(struct hid_device *hdev)
+{
+	struct pk_device *pk = (struct pk_device *)hid_get_drvdata(hdev);
+	struct pcmidi_snd *pm;
+
+	pm = pk->pm;
+	if (pm) {
+		pcmidi_snd_terminate(pm);
+		kfree(pm);
+	}
+
+	hid_hw_stop(hdev);
+
+	kfree(pk);
+}
+
+static const struct hid_device_id pk_devices[] = {
+	{HID_USB_DEVICE(USB_VENDOR_ID_CREATIVELABS,
+		USB_DEVICE_ID_PRODIKEYS_PCMIDI),
+	    .driver_data = PK_QUIRK_NOGET},
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, pk_devices);
+
+static struct hid_driver pk_driver = {
+	.name = "prodikeys",
+	.id_table = pk_devices,
+	.report_fixup = pk_report_fixup,
+	.input_mapping = pk_input_mapping,
+	.raw_event = pk_raw_event,
+	.probe = pk_probe,
+	.remove = pk_remove,
+};
+
+static int pk_init(void)
+{
+	int ret;
+
+	ret = hid_register_driver(&pk_driver);
+	if (ret)
+		printk(KERN_ERR "can't register prodikeys driver\n");
+
+	return ret;
+}
+
+static void pk_exit(void)
+{
+	hid_unregister_driver(&pk_driver);
+}
+
+module_init(pk_init);
+module_exit(pk_exit);
+MODULE_LICENSE("GPL");