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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 | /* * ALSA sequencer System services Client * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl> * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include <sound/driver.h> #include <linux/init.h> #include <sound/core.h> #include "seq_system.h" #include "seq_timer.h" #include "seq_queue.h" /* internal client that provide system services, access to timer etc. */ /* * Port "Timer" * - send tempo /start/stop etc. events to this port to manipulate the * queue's timer. The queue address is specified in * data.queue.queue. * - this port supports subscription. The received timer events are * broadcasted to all subscribed clients. The modified tempo * value is stored on data.queue.value. * The modifier client/port is not send. * * Port "Announce" * - does not receive message * - supports supscription. For each client or port attaching to or * detaching from the system an announcement is send to the subscribed * clients. * * Idea: the subscription mechanism might also work handy for distributing * synchronisation and timing information. In this case we would ideally have * a list of subscribers for each type of sync (time, tick), for each timing * queue. * * NOTE: the queue to be started, stopped, etc. must be specified * in data.queue.addr.queue field. queue is used only for * scheduling, and no longer referred as affected queue. * They are used only for timer broadcast (see above). * -- iwai */ /* client id of our system client */ static int sysclient = -1; /* port id numbers for this client */ static int announce_port = -1; /* fill standard header data, source port & channel are filled in */ static int setheader(snd_seq_event_t * ev, int client, int port) { if (announce_port < 0) return -ENODEV; memset(ev, 0, sizeof(snd_seq_event_t)); ev->flags &= ~SNDRV_SEQ_EVENT_LENGTH_MASK; ev->flags |= SNDRV_SEQ_EVENT_LENGTH_FIXED; ev->source.client = sysclient; ev->source.port = announce_port; ev->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS; /* fill data */ /*ev->data.addr.queue = SNDRV_SEQ_ADDRESS_UNKNOWN;*/ ev->data.addr.client = client; ev->data.addr.port = port; return 0; } /* entry points for broadcasting system events */ void snd_seq_system_broadcast(int client, int port, int type) { snd_seq_event_t ev; if (setheader(&ev, client, port) < 0) return; ev.type = type; snd_seq_kernel_client_dispatch(sysclient, &ev, 0, 0); } /* entry points for broadcasting system events */ int snd_seq_system_notify(int client, int port, snd_seq_event_t *ev) { ev->flags = SNDRV_SEQ_EVENT_LENGTH_FIXED; ev->source.client = sysclient; ev->source.port = announce_port; ev->dest.client = client; ev->dest.port = port; return snd_seq_kernel_client_dispatch(sysclient, ev, 0, 0); } /* call-back handler for timer events */ static int event_input_timer(snd_seq_event_t * ev, int direct, void *private_data, int atomic, int hop) { return snd_seq_control_queue(ev, atomic, hop); } /* register our internal client */ int __init snd_seq_system_client_init(void) { snd_seq_client_callback_t callbacks; snd_seq_port_callback_t pcallbacks; snd_seq_client_info_t inf; snd_seq_port_info_t port; memset(&callbacks, 0, sizeof(callbacks)); memset(&pcallbacks, 0, sizeof(pcallbacks)); memset(&inf, 0, sizeof(inf)); memset(&port, 0, sizeof(port)); pcallbacks.owner = THIS_MODULE; pcallbacks.event_input = event_input_timer; /* register client */ callbacks.allow_input = callbacks.allow_output = 1; sysclient = snd_seq_create_kernel_client(NULL, 0, &callbacks); /* set our name */ inf.client = 0; inf.type = KERNEL_CLIENT; strcpy(inf.name, "System"); snd_seq_kernel_client_ctl(sysclient, SNDRV_SEQ_IOCTL_SET_CLIENT_INFO, &inf); /* register timer */ strcpy(port.name, "Timer"); port.capability = SNDRV_SEQ_PORT_CAP_WRITE; /* accept queue control */ port.capability |= SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ; /* for broadcast */ port.kernel = &pcallbacks; port.type = 0; port.flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; port.addr.client = sysclient; port.addr.port = SNDRV_SEQ_PORT_SYSTEM_TIMER; snd_seq_kernel_client_ctl(sysclient, SNDRV_SEQ_IOCTL_CREATE_PORT, &port); /* register announcement port */ strcpy(port.name, "Announce"); port.capability = SNDRV_SEQ_PORT_CAP_READ|SNDRV_SEQ_PORT_CAP_SUBS_READ; /* for broadcast only */ port.kernel = NULL; port.type = 0; port.flags = SNDRV_SEQ_PORT_FLG_GIVEN_PORT; port.addr.client = sysclient; port.addr.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE; snd_seq_kernel_client_ctl(sysclient, SNDRV_SEQ_IOCTL_CREATE_PORT, &port); announce_port = port.addr.port; return 0; } /* unregister our internal client */ void __exit snd_seq_system_client_done(void) { int oldsysclient = sysclient; if (oldsysclient >= 0) { sysclient = -1; announce_port = -1; snd_seq_delete_kernel_client(oldsysclient); } } |