jack alsa: implement restart request [2/3]

in case ALSA_DRIVER_FEAT_CLOSE_IDLE_DEVS is defined unused devices are
closed on restart request, otherwise unused devices will be kept in
prepared state

Change-Id: I0cd91deb957a4839c5ea8c679bdabe1d0a3c6720
Signed-off-by: Adam Miartus <amiartus@de.adit-jv.com>
(cherry picked from commit ee4fe3fde6)
Signed-off-by: Timo Wischer <twischer@de.adit-jv.com>

linux/alsa/JackAlsaDriver.cpp

@@ -564,6 +564,8 @@ int JackAlsaDriver::TargetState(int init, int connections_count)
         state = SND_PCM_STATE_RUNNING;
     } else if (init) {
         state = SND_PCM_STATE_RUNNING;
+    } else if (driver->features & ALSA_DRIVER_FEAT_CLOSE_IDLE_DEVS) {
+        state = SND_PCM_STATE_NOTREADY;
     } else {
         state = SND_PCM_STATE_PREPARED;
     }
@@ -858,6 +860,9 @@ SERVER_EXPORT const jack_driver_desc_t* driver_get_descriptor ()
         "ALSA MIDI driver",
         NULL);
 
+    value.i = 0;
+    jack_driver_descriptor_add_parameter(desc, &filler, "close-idle-devs", 'c', JackDriverParamBool, &value, NULL, "Close idle devices on alsa driver restart request", NULL);
+
     return desc;
 }
 
@@ -1043,6 +1048,11 @@ SERVER_EXPORT Jack::JackDriverClientInterface* driver_initialize(Jack::JackLocke
                 free(info.midi_name);
                 info.midi_name = strdup(param->value.str);
                 break;
+
+            case 'c':
+                info.features |= param->value.i ? ALSA_DRIVER_FEAT_CLOSE_IDLE_DEVS : 0;
+                break;
+
         }
     }
 

linux/alsa/alsa_driver.c

@@ -1387,7 +1387,7 @@ alsa_driver_open (alsa_driver_t *driver)
 		alsa_device_t *device = &driver->devices[i];
 		int do_capture = 0, do_playback = 0;
 
-		if (!device->capture_handle && (i <driver->devices_c_count)) {
+		if (!device->capture_handle && (i <driver->devices_c_count) && (device->capture_target_state != SND_PCM_STATE_NOTREADY)) {
 			err = alsa_driver_open_device (driver, &driver->devices[i], SND_PCM_STREAM_CAPTURE);
 			if (err < 0) {
 				jack_error ("\n\nATTENTION: Opening of the capture device \"%s\" failed.",
@@ -1398,7 +1398,7 @@ alsa_driver_open (alsa_driver_t *driver)
 			do_capture = 1;
 		}
 
-		if (!device->playback_handle && (i <driver->devices_p_count)) {
+		if (!device->playback_handle && (i <driver->devices_p_count) && (device->playback_target_state != SND_PCM_STATE_NOTREADY)) {
 			err = alsa_driver_open_device (driver, &driver->devices[i], SND_PCM_STREAM_PLAYBACK);
 			if (err < 0) {
 				jack_error ("\n\nATTENTION: Opening of the playback device \"%s\" failed.",

linux/alsa/alsa_driver.h

@@ -58,14 +58,19 @@
 #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_STATE_NOTREADY     SND_PCM_STATUS_NOTREADY
 #define SND_PCM_STREAM_PLAYBACK    SND_PCM_CHANNEL_PLAYBACK
 #define SND_PCM_STREAM_CAPTURE     SND_PCM_CHANNEL_CAPTURE
 
 typedef unsigned long              snd_pcm_uframes_t;
 typedef signed long                snd_pcm_sframes_t;
 typedef int32_t                    alsa_driver_default_format_t;
+#else
+#define SND_PCM_STATE_NOTREADY     (SND_PCM_STATE_LAST + 1)
 #endif
 
+#define ALSA_DRIVER_FEAT_CLOSE_IDLE_DEVS   (1 << 1)
+
 #ifdef __cplusplus
 extern "C"
 {