jack alsa: implement restart request [1/3]

on restart request desired state of devices is evaluated, devices will be
closed, left prepared, started depending on selected options or their usage
(number or connected ports)

Change-Id: Id512e013556169dfc3837fd5f10845848a211d5b
Signed-off-by: Adam Miartus <amiartus@de.adit-jv.com>
(cherry picked from commit 9bdb9d09de)
Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>

linux/alsa/JackAlsaDriver.cpp

@@ -349,6 +349,12 @@ int JackAlsaDriver::Open(alsa_driver_info_t info)
     fDriver = alsa_driver_new ((char*)"alsa_pcm", info, NULL);
 
     if (fDriver) {
+        /* we need to initialize variables for all devices, mainly channels count since this is required by Jack to setup ports */
+        UpdateDriverTargetState(1);
+        if (alsa_driver_open((alsa_driver_t *)fDriver) < 0) {
+            Close();
+            return -1;
+        }
         // ALSA driver may have changed the in/out values
         fCaptureChannels = ((alsa_driver_t *)fDriver)->capture_nchannels;
         fPlaybackChannels = ((alsa_driver_t *)fDriver)->playback_nchannels;
@@ -360,6 +366,7 @@ int JackAlsaDriver::Open(alsa_driver_info_t info)
             }
         }
 #endif
+
         return 0;
     } else {
         Close();
@@ -372,6 +379,8 @@ int JackAlsaDriver::Close()
     // Generic audio driver close
     int res = JackAudioDriver::Close();
 
+    alsa_driver_close((alsa_driver_t *)fDriver);
+
     if (fDriver) {
         alsa_driver_delete((alsa_driver_t*)fDriver);
     }
@@ -424,6 +433,23 @@ int JackAlsaDriver::Stop()
     return res;
 }
 
+int JackAlsaDriver::Reload()
+{
+    UpdateDriverTargetState();
+
+    alsa_driver_t* driver = (alsa_driver_t*) fDriver;
+    if (alsa_driver_close (driver) < 0) {
+        jack_error("JackAlsaDriver::Reload close failed");
+        return -1;
+    }
+    if (alsa_driver_open (driver) < 0) {
+        jack_error("JackAlsaDriver::Reload open failed");
+        return -1;
+    }
+
+    return 0;
+}
+
 int JackAlsaDriver::Read()
 {
     /* Taken from alsa_driver_run_cycle */
@@ -503,6 +529,48 @@ int JackAlsaDriver::PortSetDefaultMetadata(jack_port_id_t port_id, const char* p
     return fEngine->PortSetDefaultMetadata(fClientControl.fRefNum, port_id, pretty_name);
 }
 
+int JackAlsaDriver::UpdateDriverTargetState(int init)
+{
+    int c_list_index = 0, p_list_index = 0;
+    alsa_driver_t* driver = (alsa_driver_t*) fDriver;
+
+    for (int i = 0; i < driver->devices_count; ++i) {
+        alsa_device_t *device = &driver->devices[i];
+
+        int capture_connections_count = 0;
+        for (int j = 0; j < device->capture_nchannels; ++j) {
+            capture_connections_count += fGraphManager->GetConnectionsNum(fCapturePortList[c_list_index]);
+            c_list_index++;
+        }
+        device->capture_target_state = TargetState(init, capture_connections_count);
+
+        int playback_connections_count = 0;
+        for (int j = 0; j < device->playback_nchannels; ++j) {
+            playback_connections_count += fGraphManager->GetConnectionsNum(fPlaybackPortList[p_list_index]);
+            p_list_index++;
+        }
+        device->playback_target_state = TargetState(init, playback_connections_count);
+    }
+
+    return 0;
+}
+
+int JackAlsaDriver::TargetState(int init, int connections_count)
+{
+    alsa_driver_t* driver = (alsa_driver_t*) fDriver;
+    int state = SND_PCM_STATE_PREPARED;
+
+    if (connections_count > 0) {
+        state = SND_PCM_STATE_RUNNING;
+    } else if (init) {
+        state = SND_PCM_STATE_RUNNING;
+    } else {
+        state = SND_PCM_STATE_PREPARED;
+    }
+
+    return state;
+}
+
 void JackAlsaDriver::WriteOutputAux(alsa_device_t *device, jack_nframes_t orig_nframes, snd_pcm_sframes_t contiguous, snd_pcm_sframes_t nwritten)
 {
     /* global channel offset to fPlaybackPortList of this playback alsa device */

linux/alsa/JackAlsaDriver.h

@@ -59,6 +59,7 @@ class JackAlsaDriver : public JackAudioDriver
 
         int Start();
         int Stop();
+        int Reload();
 
         int Read();
         int Write();
@@ -79,6 +80,10 @@ class JackAlsaDriver : public JackAudioDriver
 
         int PortSetDefaultMetadata(jack_port_id_t port_id, const char* pretty_name);
 
+        int UpdateDriverTargetState(int init = 0);
+
+        int TargetState(int init, int connections_count);
+
         // JACK API emulation for the midi driver
         int is_realtime() const;
         int create_thread(pthread_t *thread, int prio, int rt, void *(*start_func)(void*), void *arg);

linux/alsa/alsa_driver.h

@@ -54,8 +54,10 @@
 #define SND_PCM_FORMAT_S32_LE      SND_PCM_SFMT_S32_LE
 #define SND_PCM_FORMAT_S32_BE      SND_PCM_SFMT_S32_BE
 #define SND_PCM_FORMAT_FLOAT_LE    SND_PCM_SFMT_FLOAT_LE
+#define SND_PCM_STATE_PREPARED     SND_PCM_STATUS_PREPARED
 #define SND_PCM_STATE_SUSPENDED    SND_PCM_STATUS_SUSPENDED
 #define SND_PCM_STATE_XRUN         SND_PCM_STATUS_UNDERRUN
+#define SND_PCM_STATE_RUNNING      SND_PCM_STATUS_RUNNING
 #define SND_PCM_STREAM_PLAYBACK    SND_PCM_CHANNEL_PLAYBACK
 #define SND_PCM_STREAM_CAPTURE     SND_PCM_CHANNEL_CAPTURE
 
@@ -128,13 +130,17 @@ typedef struct _alsa_device {
     unsigned long playback_sample_bytes;
     unsigned long capture_sample_bytes;
 
-    /* is this device linked to first device */
+    /* device is 'snd_pcm_link' to a group, only 1 group of linked devices is allowed */
     int capture_linked;
     int playback_linked;
 
     int capture_xrun_count;
     int playback_xrun_count;
 
+    /* desired state of device, decided by JackAlsaDriver */
+    int capture_target_state;
+    int playback_target_state;
+
     jack_hardware_t *hw;
     char *alsa_driver;
 } alsa_device_t;
@@ -198,6 +204,8 @@ typedef struct _alsa_driver {
     int devices_count;
     int devices_c_count;
     int devices_p_count;
+
+    int features;
 } alsa_driver_t;
 
 typedef struct _alsa_device_info {
@@ -232,6 +240,8 @@ typedef struct _alsa_driver_info {
     int hw_metering;
     int monitor;
     int soft_mode;
+
+    int features;
 } alsa_driver_info_t;
 
 static inline void
@@ -311,12 +321,18 @@ alsa_driver_new (char *name, alsa_driver_info_t info, jack_client_t *client);
 void
 alsa_driver_delete (alsa_driver_t *driver);
 
+int
+alsa_driver_open (alsa_driver_t *driver);
+
 int
 alsa_driver_start (alsa_driver_t *driver);
 
 int
 alsa_driver_stop (alsa_driver_t *driver);
 
+int
+alsa_driver_close (alsa_driver_t *driver);
+
 jack_nframes_t
 alsa_driver_wait (alsa_driver_t *driver, int extra_fd, int *status, float
 		  *delayed_usecs);
@@ -334,6 +350,7 @@ void MonitorInput();
 void ClearOutput();
 void WriteOutput(alsa_device_t *device, jack_nframes_t orig_nframes, snd_pcm_sframes_t contiguous, snd_pcm_sframes_t nwritten);
 void SetTime(jack_time_t time);
+
 int Restart();
 
 #ifdef __cplusplus