Imported Upstream version 4.2-build2006upstream/4.2-build2006upstream

1 files changed, 346 insertions, 0 deletions

diff --git a/kernel/drv/oss_midimix/oss_midimix.c b/kernel/drv/oss_midimix/oss_midimix.c
new file mode 100644
index 0000000..9f7cc4c
--- /dev/null
+++ b/kernel/drv/oss_midimix/oss_midimix.c
@@ -0,0 +1,346 @@
+/*
+ * Purpose: MIDI mixer pseudo driver
+ *
+ * This driver creates a pseudo MIDI port device that can be used for
+ * real-time mixer volume changes. The pseudo MIDI device will return MIDI
+ * control change messages when a mixer setting changes. Application using the
+ * device may also do mixer changes (cross fading, etc) by sending (or
+ * playing back) control messages.
+ */
+/*
+ *
+ * This file is part of Open Sound System.
+ *
+ * Copyright (C) 4Front Technologies 1996-2008.
+ *
+ * This this source file is released under GPL v2 license (no other versions).
+ * See the COPYING file included in the main directory of this source
+ * distribution for the license terms and conditions.
+ *
+ */
+
+#include "oss_midimix_cfg.h"
+#include "midi_core.h"
+#include "midiparser.h"
+
+#define MAX_INSTANCES	1
+
+typedef struct
+{
+  oss_device_t *osdev;
+  oss_mutex_t mutex;
+  int midi_dev;
+  int open_mode;
+  oss_midi_inputbuf_t inputbuf;
+  midiparser_common_p parser;
+  int modify_counters[16];
+  int update_counters[16][128];
+  timeout_id_t timeout_id;
+} midimix_devc;
+
+static midimix_devc midimix_devs[MAX_INSTANCES] = {{ 0 }};
+static int ndevs = 0;
+
+static void
+midimix_close (int dev, int mode)
+{
+  midimix_devc *devc = midi_devs[dev]->devc;
+  oss_native_word flags;
+
+  midiparser_unalloc (devc->parser);
+  devc->parser = NULL;
+  untimeout (devc->timeout_id);
+
+  MUTEX_ENTER_IRQDISABLE (devc->mutex, flags);
+  devc->open_mode = 0;
+  devc->inputbuf = NULL;
+  MUTEX_EXIT_IRQRESTORE (devc->mutex, flags);
+}
+
+void
+parser_cb (void *context, int category, unsigned char msg, unsigned char ch,
+	   unsigned char *parms, int len)
+{
+
+  if (category == CAT_CHN && msg == MIDI_CTL_CHANGE)
+    {
+      oss_mixext *ext;
+      oss_mixer_value rec;
+
+      int dev = ch;
+      int ctl = parms[0];
+      int val = parms[1];
+
+      if ((ext = mixer_find_ext (dev, ctl)) == NULL)
+	return;			/* Not found */
+
+      if (!(ext->flags & MIXF_READABLE) || !(ext->flags & MIXF_WRITEABLE))
+	return;			/* Not accessible */
+
+      if (ext->maxvalue > 127)
+	val = (val * ext->maxvalue + 63) / 127;
+
+      if (val < 0 || val > ext->maxvalue)
+	return;			/* Value out of range */
+
+      switch (ext->type)
+	{
+	case MIXT_MONOSLIDER:
+	case MIXT_STEREOSLIDER:
+	  val = val & 0xff;
+	  val = val | (val << 8);
+	  break;
+
+	case MIXT_ONOFF:
+	  val = !!val;
+	  break;
+
+	case MIXT_ENUM:
+	  if (val >= ext->maxvalue)
+	    return;		/* Out of range */
+	  break;
+
+	case MIXT_VALUE:
+	case MIXT_HEXVALUE:
+	case MIXT_SLIDER:
+	  /* Accept as-is */
+	  break;
+
+	default:
+	  return;		/* Type not supported */
+	}
+
+      memset (&rec, 0, sizeof (rec));
+      rec.dev = dev;
+      rec.ctrl = ctl;
+      rec.value = val;
+      rec.timestamp = ext->timestamp;
+      oss_mixer_ext (dev, OSS_DEV_MIXER, SNDCTL_MIX_WRITE, (ioctl_arg) & rec);
+    }
+
+}
+
+static void
+check_for_updates (midimix_devc * devc, int force)
+{
+  int dev, ctl;
+
+  for (dev = 0; dev < 16 && dev < num_mixers; dev++)
+    {
+      touch_mixer (dev);
+
+      if (force
+	  || (mixer_devs[dev]->modify_counter > devc->modify_counters[dev]))
+	{
+	  devc->modify_counters[dev] = mixer_devs[dev]->modify_counter;
+	  for (ctl = 0; ctl < 128; ctl++)
+	    {
+	      oss_mixext *ext;
+	      oss_mixer_value rec;
+	      int val;
+	      unsigned char midibuf[3];
+
+	      if ((ext = mixer_find_ext (dev, ctl)) == NULL)
+		break;		/* All controls processed I think */
+	      if (!(ext->flags & MIXF_READABLE)
+		  || !(ext->flags & MIXF_WRITEABLE))
+		continue;	/* Not accessible */
+
+	      if (!force
+		  && devc->update_counters[dev][ctl] == ext->update_counter)
+		continue;	/* No change */
+	      devc->update_counters[dev][ctl] = ext->update_counter;
+
+	      switch (ext->type)
+		{
+		case MIXT_MONOSLIDER:
+		case MIXT_STEREOSLIDER:
+		case MIXT_ONOFF:
+		case MIXT_ENUM:
+		case MIXT_VALUE:
+		case MIXT_HEXVALUE:
+		case MIXT_SLIDER:
+		  /* Type OK */
+		  break;
+
+		default:
+		  continue;	/* Type not supported */
+		}
+
+	      memset (&rec, 0, sizeof (rec));
+	      rec.dev = dev;
+	      rec.ctrl = ctl;
+	      rec.timestamp = ext->timestamp;
+
+	      if (oss_mixer_ext
+		  (dev, OSS_DEV_MIXER, SNDCTL_MIX_READ,
+		   (ioctl_arg) & rec) < 0)
+		{
+		  continue;	/* Read failed */
+		}
+
+	      val = rec.value & 0xff;
+	      if (ext->maxvalue > 127)
+		val = (val * 127 + (ext->maxvalue / 2)) / ext->maxvalue;
+
+	      if (val < 0)
+		val = 0;
+	      if (val > 127)
+		val = 127;
+
+	      midibuf[0] = 0xb0 | dev;
+	      midibuf[1] = ctl;
+	      midibuf[2] = val;
+
+	      devc->inputbuf (devc->midi_dev, midibuf, 3);
+	    }
+	}
+    }
+}
+
+static void
+timer_callback (void *arg)
+{
+  midimix_devc *devc = arg;
+  check_for_updates (devc, 0);
+  devc->timeout_id = timeout (timer_callback, devc, OSS_HZ / 10);	/* 0.1s */
+}
+
+static int
+midimix_open (int dev, int mode, oss_midi_inputbyte_t inputbyte,
+	      oss_midi_inputbuf_t inputbuf, oss_midi_outputintr_t outputintr)
+{
+  midimix_devc *devc = midi_devs[dev]->devc;
+  oss_native_word flags;
+
+  MUTEX_ENTER_IRQDISABLE (devc->mutex, flags);
+  if (devc->open_mode)
+    {
+      MUTEX_EXIT_IRQRESTORE (devc->mutex, flags);
+      return OSS_EBUSY;
+    }
+  devc->open_mode = mode;
+  devc->inputbuf = inputbuf;
+  MUTEX_EXIT_IRQRESTORE (devc->mutex, flags);
+
+  if ((devc->parser = midiparser_create (parser_cb, devc)) == NULL)
+    {
+      devc->open_mode = 0;
+      devc->inputbuf = NULL;
+      cmn_err (CE_WARN, "Cannot create MIDI parser\n");
+      return OSS_ENOMEM;
+    }
+
+  devc->timeout_id = timeout (timer_callback, devc, OSS_HZ / 10);	/* 0.1s */
+  return 0;
+}
+
+static int
+midimix_ioctl (int dev, unsigned cmd, ioctl_arg arg)
+{
+  return OSS_EINVAL;
+}
+
+static int
+midimix_out (int dev, unsigned char midi_byte)
+{
+  midimix_devc *devc = midi_devs[dev]->devc;
+  oss_native_word flags;
+
+  MUTEX_ENTER_IRQDISABLE (devc->mutex, flags);
+  midiparser_input (devc->parser, midi_byte);
+  MUTEX_EXIT_IRQRESTORE (devc->mutex, flags);
+  return 1;
+}
+
+static int
+midimix_bulk_out (int dev, unsigned char *buf, int len)
+{
+  midimix_devc *devc = midi_devs[dev]->devc;
+  int i;
+  oss_native_word flags;
+
+  MUTEX_ENTER_IRQDISABLE (devc->mutex, flags);
+  for (i = 0; i < len; i++)
+    {
+      midiparser_input (devc->parser, buf[i]);
+    }
+  MUTEX_EXIT_IRQRESTORE (devc->mutex, flags);
+  return len;
+}
+
+static void
+midimix_init_device (int dev)
+{
+  midimix_devc *devc = midi_devs[dev]->devc;
+
+  if (devc->open_mode & OPEN_READ)
+    check_for_updates (devc, 1);
+}
+
+static midi_driver_t midimix_driver = {
+  midimix_open,
+  midimix_close,
+  midimix_ioctl,
+  midimix_out,
+  midimix_bulk_out,
+  MIDI_PAYLOAD_SIZE,
+  NULL,
+  NULL,
+  NULL,
+  midimix_init_device
+};
+
+static void
+attach_midimix_dev (oss_device_t * osdev)
+{
+  midimix_devc *devc = &midimix_devs[ndevs++];
+
+  devc->osdev = osdev;
+
+  MUTEX_INIT (osdev, devc->mutex, MH_DRV);
+
+  devc->midi_dev =
+    oss_install_mididev (OSS_MIDI_DRIVER_VERSION, "MIX",
+			 "Mixer access MIDI device", &midimix_driver,
+			 sizeof (midi_driver_t),
+			 MFLAG_VIRTUAL | MFLAG_QUIET, devc, devc->osdev);
+}
+
+int
+oss_midimix_attach (oss_device_t * osdev)
+{
+  int midimix_instances = 1;
+  int i;
+
+  oss_register_device (osdev, "OSS MIDI mixer driver");
+
+  if (midimix_instances > MAX_INSTANCES)
+    midimix_instances = MAX_INSTANCES;
+  for (i = 0; i < midimix_instances; i++)
+    {
+      attach_midimix_dev (osdev);
+    }
+
+  return 1;
+}
+
+int
+oss_midimix_detach (oss_device_t * osdev)
+{
+  int i, err;
+
+  if ((err = oss_disable_device (osdev)) < 0)
+    return 0;
+
+  for (i = 0; i < ndevs; i++)
+    {
+      midimix_devc *devc;
+
+      devc = &midimix_devs[i];
+    }
+
+  oss_unregister_device (osdev);
+
+  return 1;
+}