Implement the hwdep locking and notification mechanisms.
Signed-off-by: Clemens Ladisch clemens@ladisch.de --- sound/firewire/dice.c | 225 ++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 203 insertions(+), 22 deletions(-)
diff --git a/sound/firewire/dice.c b/sound/firewire/dice.c index d0575a9..7225878 100644 --- a/sound/firewire/dice.c +++ b/sound/firewire/dice.c @@ -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); + } + + 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 int dice_hwdep_open(struct snd_hwdep *hwdep, struct file *file) +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)