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Commit 0c29c918 authored by Clemens Ladisch's avatar Clemens Ladisch
Browse files

ALSA: dice: implement hwdep device 



Implement the hwdep locking and notification mechanisms.

Signed-off-by: default avatarClemens Ladisch <clemens@ladisch.de>
parent 4ed31f20

sound/firewire/dice.c

+203 −22
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 
 * Licensed under the terms of the GNU General Public License, version 2.

 */



#include <linux/compat.h>

#include <linux/delay.h>

#include <linux/device.h>

#include <linux/firewire.h>
@@ -13,8 +14,11 @@ 
#include <linux/mod_devicetable.h>

#include <linux/mutex.h>

#include <linux/slab.h>

#include <linux/spinlock.h>

#include <linux/wait.h>

#include <sound/control.h>

#include <sound/core.h>

#include <sound/firewire.h>

#include <sound/hwdep.h>

#include <sound/initval.h>

#include <sound/pcm.h>
@@ -233,13 +237,18 @@ 
struct dice {

	struct snd_card *card;

	struct fw_unit *unit;

	spinlock_t lock;

	struct mutex mutex;

	unsigned int global_offset;

	unsigned int rx_offset;

	struct fw_address_handler notification_handler;

	int owner_generation;

	int dev_lock_count; /* > 0 driver, < 0 userspace */

	bool dev_lock_changed;

	bool global_enabled;

	bool stream_running;

	wait_queue_head_t hwdep_wait;

	u32 notification_bits;

	struct snd_pcm_substream *pcm;

	struct fw_iso_resources resources;

	struct amdtp_out_stream stream;
@@ -259,6 +268,47 @@ static const unsigned int dice_rates[] = { 
	[6] = 192000,

};



static void dice_lock_changed(struct dice *dice)

{

	dice->dev_lock_changed = true;

	wake_up(&dice->hwdep_wait);

}



static int dice_try_lock(struct dice *dice)

{

	int err;



	spin_lock_irq(&dice->lock);



	if (dice->dev_lock_count < 0) {

		err = -EBUSY;

		goto out;

	}



	if (dice->dev_lock_count++ == 0)

		dice_lock_changed(dice);

	err = 0;



out:

	spin_unlock_irq(&dice->lock);



	return err;

}



static void dice_unlock(struct dice *dice)

{

	spin_lock_irq(&dice->lock);



	if (WARN_ON(dice->dev_lock_count <= 0))

		goto out;



	if (--dice->dev_lock_count == 0)

		dice_lock_changed(dice);



out:

	spin_unlock_irq(&dice->lock);

}



static inline u64 global_address(struct dice *dice, unsigned int offset)

{

	return DICE_PRIVATE_SPACE + dice->global_offset + offset;
@@ -496,6 +546,7 @@ static void dice_notification(struct fw_card *card, struct fw_request *request, 
			      void *data, size_t length, void *callback_data)

{

	struct dice *dice = callback_data;

	unsigned long flags;



	if (tcode != TCODE_WRITE_QUADLET_REQUEST) {

		fw_send_response(card, request, RCODE_TYPE_ERROR);
@@ -505,9 +556,11 @@ static void dice_notification(struct fw_card *card, struct fw_request *request, 
		fw_send_response(card, request, RCODE_ADDRESS_ERROR);

		return;

	}

	dev_dbg(&dice->unit->device,

		"notification: %08x\n", be32_to_cpup(data));

	spin_lock_irqsave(&dice->lock, flags);

	dice->notification_bits |= be32_to_cpup(data);

	spin_unlock_irqrestore(&dice->lock, flags);

	fw_send_response(card, request, RCODE_COMPLETE);

	wake_up(&dice->hwdep_wait);

}



static int dice_open(struct snd_pcm_substream *substream)
@@ -531,26 +584,32 @@ static int dice_open(struct snd_pcm_substream *substream) 
	unsigned int rate;

	int err;



	err = dice_try_lock(dice);

	if (err < 0)

		goto error;



	err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,

				 global_address(dice, GLOBAL_CLOCK_SELECT),

				 &clock_sel, 4);

	if (err < 0)

		return err;

		goto err_lock;

	rate = (be32_to_cpu(clock_sel) & CLOCK_RATE_MASK) >> CLOCK_RATE_SHIFT;

	if (rate >= ARRAY_SIZE(dice_rates))

		return -ENXIO;

	if (rate >= ARRAY_SIZE(dice_rates)) {

		err = -ENXIO;

		goto err_lock;

	}

	rate = dice_rates[rate];



	err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,

				 rx_address(dice, RX_NUMBER_AUDIO),

				 &number_audio, 4);

	if (err < 0)

		return err;

		goto err_lock;

	err = snd_fw_transaction(dice->unit, TCODE_READ_QUADLET_REQUEST,

				 rx_address(dice, RX_NUMBER_MIDI),

				 &number_midi, 4);

	if (err < 0)

		return err;

		goto err_lock;



	runtime->hw = hardware;
@@ -568,17 +627,26 @@ static int dice_open(struct snd_pcm_substream *substream) 
					   SNDRV_PCM_HW_PARAM_PERIOD_TIME,

					   5000, 8192000);

	if (err < 0)

		return err;

		goto err_lock;



	err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);

	if (err < 0)

		return err;

		goto err_lock;



	return 0;



err_lock:

	dice_unlock(dice);

error:

	return err;

}



static int dice_close(struct snd_pcm_substream *substream)

{

	struct dice *dice = substream->private_data;



	dice_unlock(dice);



	return 0;

}
@@ -783,45 +851,156 @@ static int dice_create_pcm(struct dice *dice) 
	return 0;

}



// TODO: implement these



static long dice_hwdep_read(struct snd_hwdep *hwdep, char __user *buf,

			    long count, loff_t *offset)

{

	return -EIO;

	struct dice *dice = hwdep->private_data;

	DEFINE_WAIT(wait);

	union snd_firewire_event event;



	spin_lock_irq(&dice->lock);



	while (!dice->dev_lock_changed && dice->notification_bits == 0) {

		prepare_to_wait(&dice->hwdep_wait, &wait, TASK_INTERRUPTIBLE);

		spin_unlock_irq(&dice->lock);

		schedule();

		finish_wait(&dice->hwdep_wait, &wait);

		if (signal_pending(current))

			return -ERESTARTSYS;

		spin_lock_irq(&dice->lock);

	}



static int dice_hwdep_open(struct snd_hwdep *hwdep, struct file *file)

	memset(&event, 0, sizeof(event));

	if (dice->dev_lock_changed) {

		event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;

		event.lock_status.status = dice->dev_lock_count > 0;

		dice->dev_lock_changed = false;



		count = min(count, (long)sizeof(event.lock_status));

	} else {

		event.dice_notification.type = SNDRV_FIREWIRE_EVENT_DICE_NOTIFICATION;

		event.dice_notification.notification = dice->notification_bits;

		dice->notification_bits = 0;



		count = min(count, (long)sizeof(event.dice_notification));

	}



	spin_unlock_irq(&dice->lock);



	if (copy_to_user(buf, &event, count))

		return -EFAULT;



	return count;

}



static unsigned int dice_hwdep_poll(struct snd_hwdep *hwdep, struct file *file,

				    poll_table *wait)

{

	return -EIO;

	struct dice *dice = hwdep->private_data;

	unsigned int events;



	poll_wait(file, &dice->hwdep_wait, wait);



	spin_lock_irq(&dice->lock);

	if (dice->dev_lock_changed || dice->notification_bits != 0)

		events = POLLIN | POLLRDNORM;

	else

		events = 0;

	spin_unlock_irq(&dice->lock);



	return events;

}



static int dice_hwdep_release(struct snd_hwdep *hwdep, struct file *file)

static int dice_hwdep_get_info(struct dice *dice, void __user *arg)

{

	struct fw_device *dev = fw_parent_device(dice->unit);

	struct snd_firewire_get_info info;



	memset(&info, 0, sizeof(info));

	info.type = SNDRV_FIREWIRE_TYPE_DICE;

	info.card = dev->card->index;

	*(__be32 *)&info.guid[0] = cpu_to_be32(dev->config_rom[3]);

	*(__be32 *)&info.guid[4] = cpu_to_be32(dev->config_rom[4]);

	strlcpy(info.device_name, dev_name(&dev->device),

		sizeof(info.device_name));



	if (copy_to_user(arg, &info, sizeof(info)))

		return -EFAULT;



	return 0;

}



static unsigned int dice_hwdep_poll(struct snd_hwdep *hwdep, struct file *file,

				    poll_table *wait)

static int dice_hwdep_lock(struct dice *dice)

{

	int err;



	spin_lock_irq(&dice->lock);



	if (dice->dev_lock_count == 0) {

		dice->dev_lock_count = -1;

		err = 0;

	} else {

		err = -EBUSY;

	}



	spin_unlock_irq(&dice->lock);



	return err;

}



static int dice_hwdep_unlock(struct dice *dice)

{

	return POLLERR | POLLHUP;

	int err;



	spin_lock_irq(&dice->lock);



	if (dice->dev_lock_count == -1) {

		dice->dev_lock_count = 0;

		err = 0;

	} else {

		err = -EBADFD;

	}



	spin_unlock_irq(&dice->lock);



	return err;

}



static int dice_hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,

			    unsigned int cmd, unsigned long arg)

{

	return -EIO;

	struct dice *dice = hwdep->private_data;



	switch (cmd) {

	case SNDRV_FIREWIRE_IOCTL_GET_INFO:

		return dice_hwdep_get_info(dice, (void __user *)arg);

	case SNDRV_FIREWIRE_IOCTL_LOCK:

		return dice_hwdep_lock(dice);

	case SNDRV_FIREWIRE_IOCTL_UNLOCK:

		return dice_hwdep_unlock(dice);

	default:

		return -ENOIOCTLCMD;

	}

}



#ifdef CONFIG_COMPAT

static int dice_hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,

				   unsigned int cmd, unsigned long arg)

{

	return dice_hwdep_ioctl(hwdep, file, cmd,

				(unsigned long)compat_ptr(arg));

}

#else

#define dice_hwdep_compat_ioctl NULL

#endif



static int dice_create_hwdep(struct dice *dice)

{

	static const struct snd_hwdep_ops ops = {

		.read         = dice_hwdep_read,

		.open         = dice_hwdep_open,

		.release      = dice_hwdep_release,

		.poll         = dice_hwdep_poll,

		.ioctl        = dice_hwdep_ioctl,

		.ioctl_compat = dice_hwdep_ioctl,

		.ioctl_compat = dice_hwdep_compat_ioctl,

	};

	struct snd_hwdep *hwdep;

	int err;
@@ -922,8 +1101,10 @@ static int dice_probe(struct fw_unit *unit, const struct ieee1394_device_id *id) 


	dice = card->private_data;

	dice->card = card;

	spin_lock_init(&dice->lock);

	mutex_init(&dice->mutex);

	dice->unit = unit;

	init_waitqueue_head(&dice->hwdep_wait);



	err = dice_init_offsets(dice);

	if (err < 0)