ALSA: fireworks: Add hwdep interface

This interface is designed for mixer/control application. To use hwdep
interface, the application can get information about firewire node, can
lock/unlock kernel streaming and can get notification at starting/stopping
kernel streaming.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

10 files changed, 296 insertions, 8 deletions

diff --git a/include/uapi/sound/asound.h b/include/uapi/sound/asound.h
index 9fc6219d3848..5dfbfdfd2d12 100644
--- a/include/uapi/sound/asound.h
+++ b/include/uapi/sound/asound.h
@@ -94,9 +94,10 @@ enum {
         SNDRV_HWDEP_IFACE_HDA,          /* HD-audio */
         SNDRV_HWDEP_IFACE_USB_STREAM,   /* direct access to usb stream */
         SNDRV_HWDEP_IFACE_FW_DICE,      /* TC DICE FireWire device */
+        SNDRV_HWDEP_IFACE_FW_FIREWORKS, /* Echo Audio Fireworks based device */
 
         /* Don't forget to change the following: */
-        SNDRV_HWDEP_IFACE_LAST = SNDRV_HWDEP_IFACE_FW_DICE
+        SNDRV_HWDEP_IFACE_LAST = SNDRV_HWDEP_IFACE_FW_FIREWORKS
 };
 
 struct snd_hwdep_info {
diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h
index 59f5961302bf..fc9afb261989 100644
--- a/include/uapi/sound/firewire.h
+++ b/include/uapi/sound/firewire.h
@@ -34,7 +34,8 @@ union snd_firewire_event {
 #define SNDRV_FIREWIRE_IOCTL_UNLOCK    _IO('H', 0xfa)
 
 #define SNDRV_FIREWIRE_TYPE_DICE        1
-/* Fireworks, AV/C, RME, MOTU, ... */
+#define SNDRV_FIREWIRE_TYPE_FIREWORKS   2
+/* AV/C, RME, MOTU, ... */
 
 struct snd_firewire_get_info {
         unsigned int type; /* SNDRV_FIREWIRE_TYPE_xxx */
diff --git a/sound/firewire/Kconfig b/sound/firewire/Kconfig
index fb39f9cfdfbf..875af0217916 100644
--- a/sound/firewire/Kconfig
+++ b/sound/firewire/Kconfig
@@ -66,6 +66,7 @@ config SND_FIREWORKS
         select SND_FIREWIRE_LIB
         select SND_RAWMIDI
         select SND_PCM
+        select SND_HWDEP
         help
           Say Y here to include support for FireWire devices based
           on Echo Digital Audio Fireworks board:
diff --git a/sound/firewire/fireworks/Makefile b/sound/firewire/fireworks/Makefile
index d7ebf834fece..0c7440826db8 100644
--- a/sound/firewire/fireworks/Makefile
+++ b/sound/firewire/fireworks/Makefile
@@ -1,4 +1,4 @@
 snd-fireworks-objs := fireworks_transaction.o fireworks_command.o \
                       fireworks_stream.o fireworks_proc.o fireworks_midi.o \
-                      fireworks_pcm.o fireworks.o
+                      fireworks_pcm.o fireworks_hwdep.o fireworks.o
 obj-m += snd-fireworks.o
diff --git a/sound/firewire/fireworks/fireworks.c b/sound/firewire/fireworks/fireworks.c
index d7877c79e32f..f8d06f56618f 100644
--- a/sound/firewire/fireworks/fireworks.c
+++ b/sound/firewire/fireworks/fireworks.c
@@ -217,6 +217,7 @@ efw_probe(struct fw_unit *unit,
         efw->unit = unit;
         mutex_init(&efw->mutex);
         spin_lock_init(&efw->lock);
+        init_waitqueue_head(&efw->hwdep_wait);
 
         err = get_hardware_info(efw);
         if (err < 0)
@@ -236,6 +237,10 @@ efw_probe(struct fw_unit *unit,
         if (err < 0)
                 goto error;
 
+        err = snd_efw_create_hwdep_device(efw);
+        if (err < 0)
+                goto error;
+
         err = snd_efw_stream_init_duplex(efw);
         if (err < 0)
                 goto error;
diff --git a/sound/firewire/fireworks/fireworks.h b/sound/firewire/fireworks/fireworks.h
index 36419ca12d6f..4aaf2dce5ec8 100644
--- a/sound/firewire/fireworks/fireworks.h
+++ b/sound/firewire/fireworks/fireworks.h
@@ -24,6 +24,8 @@
 #include <sound/info.h>
 #include <sound/rawmidi.h>
 #include <sound/pcm_params.h>
+#include <sound/firewire.h>
+#include <sound/hwdep.h>
 
 #include "../packets-buffer.h"
 #include "../iso-resources.h"
@@ -90,6 +92,11 @@ struct snd_efw {
         unsigned int phys_in_grp_count;
         struct snd_efw_phys_grp phys_out_grps[HWINFO_MAX_CAPS_GROUPS];
         struct snd_efw_phys_grp phys_in_grps[HWINFO_MAX_CAPS_GROUPS];
+
+        /* for uapi */
+        int dev_lock_count;
+        bool dev_lock_changed;
+        wait_queue_head_t hwdep_wait;
 };
 
 struct snd_efw_transaction {
@@ -197,6 +204,9 @@ int snd_efw_stream_start_duplex(struct snd_efw *efw, int sampling_rate);
 void snd_efw_stream_stop_duplex(struct snd_efw *efw);
 void snd_efw_stream_update_duplex(struct snd_efw *efw);
 void snd_efw_stream_destroy_duplex(struct snd_efw *efw);
+void snd_efw_stream_lock_changed(struct snd_efw *efw);
+int snd_efw_stream_lock_try(struct snd_efw *efw);
+void snd_efw_stream_lock_release(struct snd_efw *efw);
 
 void snd_efw_proc_init(struct snd_efw *efw);
 
@@ -205,6 +215,8 @@ int snd_efw_create_midi_devices(struct snd_efw *efw);
 int snd_efw_create_pcm_devices(struct snd_efw *efw);
 int snd_efw_get_multiplier_mode(unsigned int sampling_rate, unsigned int *mode);
 
+int snd_efw_create_hwdep_device(struct snd_efw *efw);
+
 #define SND_EFW_DEV_ENTRY(vendor, model) \
 { \
         .match_flags    = IEEE1394_MATCH_VENDOR_ID | \
diff --git a/sound/firewire/fireworks/fireworks_hwdep.c b/sound/firewire/fireworks/fireworks_hwdep.c
new file mode 100644
index 000000000000..1cf491dc39a3
--- /dev/null
+++ b/sound/firewire/fireworks/fireworks_hwdep.c
@@ -0,0 +1,199 @@
+/*
+ * fireworks_hwdep.c - a part of driver for Fireworks based devices
+ *
+ * Copyright (c) 2013-2014 Takashi Sakamoto
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+/*
+ * This codes have three functionalities.
+ *
+ * 1.get information about firewire node
+ * 2.get notification about starting/stopping stream
+ * 3.lock/unlock streaming
+ */
+
+#include "fireworks.h"
+
+static long
+hwdep_read(struct snd_hwdep *hwdep, char __user *buf,  long count,
+           loff_t *offset)
+{
+        struct snd_efw *efw = hwdep->private_data;
+        DEFINE_WAIT(wait);
+        union snd_firewire_event event;
+
+        spin_lock_irq(&efw->lock);
+
+        while (!efw->dev_lock_changed) {
+                prepare_to_wait(&efw->hwdep_wait, &wait, TASK_INTERRUPTIBLE);
+                spin_unlock_irq(&efw->lock);
+                schedule();
+                finish_wait(&efw->hwdep_wait, &wait);
+                if (signal_pending(current))
+                        return -ERESTARTSYS;
+                spin_lock_irq(&efw->lock);
+        }
+
+        memset(&event, 0, sizeof(event));
+        if (efw->dev_lock_changed) {
+                event.lock_status.type = SNDRV_FIREWIRE_EVENT_LOCK_STATUS;
+                event.lock_status.status = (efw->dev_lock_count > 0);
+                efw->dev_lock_changed = false;
+
+                count = min_t(long, count, sizeof(event.lock_status));
+        }
+
+        spin_unlock_irq(&efw->lock);
+
+        if (copy_to_user(buf, &event, count))
+                return -EFAULT;
+
+        return count;
+}
+
+static unsigned int
+hwdep_poll(struct snd_hwdep *hwdep, struct file *file, poll_table *wait)
+{
+        struct snd_efw *efw = hwdep->private_data;
+        unsigned int events;
+
+        poll_wait(file, &efw->hwdep_wait, wait);
+
+        spin_lock_irq(&efw->lock);
+        if (efw->dev_lock_changed)
+                events = POLLIN | POLLRDNORM;
+        else
+                events = 0;
+        spin_unlock_irq(&efw->lock);
+
+        return events;
+}
+
+static int
+hwdep_get_info(struct snd_efw *efw, void __user *arg)
+{
+        struct fw_device *dev = fw_parent_device(efw->unit);
+        struct snd_firewire_get_info info;
+
+        memset(&info, 0, sizeof(info));
+        info.type = SNDRV_FIREWIRE_TYPE_FIREWORKS;
+        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 int
+hwdep_lock(struct snd_efw *efw)
+{
+        int err;
+
+        spin_lock_irq(&efw->lock);
+
+        if (efw->dev_lock_count == 0) {
+                efw->dev_lock_count = -1;
+                err = 0;
+        } else {
+                err = -EBUSY;
+        }
+
+        spin_unlock_irq(&efw->lock);
+
+        return err;
+}
+
+static int
+hwdep_unlock(struct snd_efw *efw)
+{
+        int err;
+
+        spin_lock_irq(&efw->lock);
+
+        if (efw->dev_lock_count == -1) {
+                efw->dev_lock_count = 0;
+                err = 0;
+        } else {
+                err = -EBADFD;
+        }
+
+        spin_unlock_irq(&efw->lock);
+
+        return err;
+}
+
+static int
+hwdep_release(struct snd_hwdep *hwdep, struct file *file)
+{
+        struct snd_efw *efw = hwdep->private_data;
+
+        spin_lock_irq(&efw->lock);
+        if (efw->dev_lock_count == -1)
+                efw->dev_lock_count = 0;
+        spin_unlock_irq(&efw->lock);
+
+        return 0;
+}
+
+static int
+hwdep_ioctl(struct snd_hwdep *hwdep, struct file *file,
+            unsigned int cmd, unsigned long arg)
+{
+        struct snd_efw *efw = hwdep->private_data;
+
+        switch (cmd) {
+        case SNDRV_FIREWIRE_IOCTL_GET_INFO:
+                return hwdep_get_info(efw, (void __user *)arg);
+        case SNDRV_FIREWIRE_IOCTL_LOCK:
+                return hwdep_lock(efw);
+        case SNDRV_FIREWIRE_IOCTL_UNLOCK:
+                return hwdep_unlock(efw);
+        default:
+                return -ENOIOCTLCMD;
+        }
+}
+
+#ifdef CONFIG_COMPAT
+static int
+hwdep_compat_ioctl(struct snd_hwdep *hwdep, struct file *file,
+                   unsigned int cmd, unsigned long arg)
+{
+        return hwdep_ioctl(hwdep, file, cmd,
+                           (unsigned long)compat_ptr(arg));
+}
+#else
+#define hwdep_compat_ioctl NULL
+#endif
+
+static const struct snd_hwdep_ops hwdep_ops = {
+        .read           = hwdep_read,
+        .release        = hwdep_release,
+        .poll           = hwdep_poll,
+        .ioctl          = hwdep_ioctl,
+        .ioctl_compat   = hwdep_compat_ioctl,
+};
+
+int snd_efw_create_hwdep_device(struct snd_efw *efw)
+{
+        struct snd_hwdep *hwdep;
+        int err;
+
+        err = snd_hwdep_new(efw->card, "Fireworks", 0, &hwdep);
+        if (err < 0)
+                goto end;
+        strcpy(hwdep->name, "Fireworks");
+        hwdep->iface = SNDRV_HWDEP_IFACE_FW_FIREWORKS;
+        hwdep->ops = hwdep_ops;
+        hwdep->private_data = efw;
+        hwdep->exclusive = true;
+end:
+        return err;
+}
+
diff --git a/sound/firewire/fireworks/fireworks_midi.c b/sound/firewire/fireworks/fireworks_midi.c
index cbf34e99237f..4a600d235ec5 100644
--- a/sound/firewire/fireworks/fireworks_midi.c
+++ b/sound/firewire/fireworks/fireworks_midi.c
@@ -11,17 +11,36 @@
 static int midi_capture_open(struct snd_rawmidi_substream *substream)
 {
         struct snd_efw *efw = substream->rmidi->private_data;
+        int err;
+
+        err = snd_efw_stream_lock_try(efw);
+        if (err < 0)
+                goto end;
 
         atomic_inc(&efw->capture_substreams);
-        return snd_efw_stream_start_duplex(efw, 0);
+        err = snd_efw_stream_start_duplex(efw, 0);
+        if (err < 0)
+                snd_efw_stream_lock_release(efw);
+
+end:
+        return err;
 }
 
 static int midi_playback_open(struct snd_rawmidi_substream *substream)
 {
         struct snd_efw *efw = substream->rmidi->private_data;
+        int err;
+
+        err = snd_efw_stream_lock_try(efw);
+        if (err < 0)
+                goto end;
 
         atomic_inc(&efw->playback_substreams);
-        return snd_efw_stream_start_duplex(efw, 0);
+        err = snd_efw_stream_start_duplex(efw, 0);
+        if (err < 0)
+                snd_efw_stream_lock_release(efw);
+end:
+        return err;
 }
 
 static int midi_capture_close(struct snd_rawmidi_substream *substream)
@@ -31,6 +50,7 @@ static int midi_capture_close(struct snd_rawmidi_substream *substream)
         atomic_dec(&efw->capture_substreams);
         snd_efw_stream_stop_duplex(efw);
 
+        snd_efw_stream_lock_release(efw);
         return 0;
 }
 
@@ -41,6 +61,7 @@ static int midi_playback_close(struct snd_rawmidi_substream *substream)
         atomic_dec(&efw->playback_substreams);
         snd_efw_stream_stop_duplex(efw);
 
+        snd_efw_stream_lock_release(efw);
         return 0;
 }
 
diff --git a/sound/firewire/fireworks/fireworks_pcm.c b/sound/firewire/fireworks/fireworks_pcm.c
index 15ec4e02b84f..ed211d062202 100644
--- a/sound/firewire/fireworks/fireworks_pcm.c
+++ b/sound/firewire/fireworks/fireworks_pcm.c
@@ -199,13 +199,17 @@ static int pcm_open(struct snd_pcm_substream *substream)
         unsigned int clock_source;
         int err;
 
-        err = pcm_init_hw_params(efw, substream);
+        err = snd_efw_stream_lock_try(efw);
         if (err < 0)
                 goto end;
 
+        err = pcm_init_hw_params(efw, substream);
+        if (err < 0)
+                goto err_locked;
+
         err = snd_efw_command_get_clock_source(efw, &clock_source);
         if (err < 0)
-                goto end;
+                goto err_locked;
 
         /*
          * When source of clock is not internal or any PCM streams are running,
@@ -216,7 +220,7 @@ static int pcm_open(struct snd_pcm_substream *substream)
             amdtp_stream_pcm_running(&efw->rx_stream)) {
                 err = snd_efw_command_get_sampling_rate(efw, &sampling_rate);
                 if (err < 0)
-                        goto end;
+                        goto err_locked;
                 substream->runtime->hw.rate_min = sampling_rate;
                 substream->runtime->hw.rate_max = sampling_rate;
         }
@@ -224,10 +228,15 @@ static int pcm_open(struct snd_pcm_substream *substream)
         snd_pcm_set_sync(substream);
 end:
         return err;
+err_locked:
+        snd_efw_stream_lock_release(efw);
+        return err;
 }
 
 static int pcm_close(struct snd_pcm_substream *substream)
 {
+        struct snd_efw *efw = substream->private_data;
+        snd_efw_stream_lock_release(efw);
         return 0;
 }
 
diff --git a/sound/firewire/fireworks/fireworks_stream.c b/sound/firewire/fireworks/fireworks_stream.c
index 1860914a3e0f..eaab8f6bc8b6 100644
--- a/sound/firewire/fireworks/fireworks_stream.c
+++ b/sound/firewire/fireworks/fireworks_stream.c
@@ -331,3 +331,42 @@ void snd_efw_stream_destroy_duplex(struct snd_efw *efw)
 
         mutex_unlock(&efw->mutex);
 }
+
+void snd_efw_stream_lock_changed(struct snd_efw *efw)
+{
+        efw->dev_lock_changed = true;
+        wake_up(&efw->hwdep_wait);
+}
+
+int snd_efw_stream_lock_try(struct snd_efw *efw)
+{
+        int err;
+
+        spin_lock_irq(&efw->lock);
+
+        /* user land lock this */
+        if (efw->dev_lock_count < 0) {
+                err = -EBUSY;
+                goto end;
+        }
+
+        /* this is the first time */
+        if (efw->dev_lock_count++ == 0)
+                snd_efw_stream_lock_changed(efw);
+        err = 0;
+end:
+        spin_unlock_irq(&efw->lock);
+        return err;
+}
+
+void snd_efw_stream_lock_release(struct snd_efw *efw)
+{
+        spin_lock_irq(&efw->lock);
+
+        if (WARN_ON(efw->dev_lock_count <= 0))
+                goto end;
+        if (--efw->dev_lock_count == 0)
+                snd_efw_stream_lock_changed(efw);
+end:
+        spin_unlock_irq(&efw->lock);
+}