1 /* 2 * HD-audio core bus driver 3 */ 4 5 #include <linux/init.h> 6 #include <linux/device.h> 7 #include <linux/module.h> 8 #include <linux/export.h> 9 #include <sound/hdaudio.h> 10 #include "trace.h" 11 12 static const struct hdac_bus_ops default_ops = { 13 .command = snd_hdac_bus_send_cmd, 14 .get_response = snd_hdac_bus_get_response, 15 }; 16 17 /** 18 * snd_hdac_bus_init - initialize a HD-audio bas bus 19 * @bus: the pointer to bus object 20 * @ops: bus verb operators 21 * @io_ops: lowlevel I/O operators 22 * 23 * Returns 0 if successful, or a negative error code. 24 */ 25 int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev, 26 const struct hdac_bus_ops *ops, 27 const struct hdac_io_ops *io_ops) 28 { 29 memset(bus, 0, sizeof(*bus)); 30 bus->dev = dev; 31 if (ops) 32 bus->ops = ops; 33 else 34 bus->ops = &default_ops; 35 bus->io_ops = io_ops; 36 INIT_LIST_HEAD(&bus->stream_list); 37 INIT_LIST_HEAD(&bus->codec_list); 38 INIT_WORK(&bus->unsol_work, snd_hdac_bus_process_unsol_events); 39 spin_lock_init(&bus->reg_lock); 40 mutex_init(&bus->cmd_mutex); 41 bus->irq = -1; 42 return 0; 43 } 44 EXPORT_SYMBOL_GPL(snd_hdac_bus_init); 45 46 /** 47 * snd_hdac_bus_exit - clean up a HD-audio bas bus 48 * @bus: the pointer to bus object 49 */ 50 void snd_hdac_bus_exit(struct hdac_bus *bus) 51 { 52 WARN_ON(!list_empty(&bus->stream_list)); 53 WARN_ON(!list_empty(&bus->codec_list)); 54 cancel_work_sync(&bus->unsol_work); 55 } 56 EXPORT_SYMBOL_GPL(snd_hdac_bus_exit); 57 58 /** 59 * snd_hdac_bus_exec_verb - execute a HD-audio verb on the given bus 60 * @bus: bus object 61 * @cmd: HD-audio encoded verb 62 * @res: pointer to store the response, NULL if performing asynchronously 63 * 64 * Returns 0 if successful, or a negative error code. 65 */ 66 int snd_hdac_bus_exec_verb(struct hdac_bus *bus, unsigned int addr, 67 unsigned int cmd, unsigned int *res) 68 { 69 int err; 70 71 mutex_lock(&bus->cmd_mutex); 72 err = snd_hdac_bus_exec_verb_unlocked(bus, addr, cmd, res); 73 mutex_unlock(&bus->cmd_mutex); 74 return err; 75 } 76 EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb); 77 78 /** 79 * snd_hdac_bus_exec_verb_unlocked - unlocked version 80 * @bus: bus object 81 * @cmd: HD-audio encoded verb 82 * @res: pointer to store the response, NULL if performing asynchronously 83 * 84 * Returns 0 if successful, or a negative error code. 85 */ 86 int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr, 87 unsigned int cmd, unsigned int *res) 88 { 89 unsigned int tmp; 90 int err; 91 92 if (cmd == ~0) 93 return -EINVAL; 94 95 if (res) 96 *res = -1; 97 else if (bus->sync_write) 98 res = &tmp; 99 for (;;) { 100 trace_hda_send_cmd(bus, cmd); 101 err = bus->ops->command(bus, cmd); 102 if (err != -EAGAIN) 103 break; 104 /* process pending verbs */ 105 err = bus->ops->get_response(bus, addr, &tmp); 106 if (err) 107 break; 108 } 109 if (!err && res) { 110 err = bus->ops->get_response(bus, addr, res); 111 trace_hda_get_response(bus, addr, *res); 112 } 113 return err; 114 } 115 EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb_unlocked); 116 117 /** 118 * snd_hdac_bus_queue_event - add an unsolicited event to queue 119 * @bus: the BUS 120 * @res: unsolicited event (lower 32bit of RIRB entry) 121 * @res_ex: codec addr and flags (upper 32bit or RIRB entry) 122 * 123 * Adds the given event to the queue. The events are processed in 124 * the workqueue asynchronously. Call this function in the interrupt 125 * hanlder when RIRB receives an unsolicited event. 126 */ 127 void snd_hdac_bus_queue_event(struct hdac_bus *bus, u32 res, u32 res_ex) 128 { 129 unsigned int wp; 130 131 if (!bus) 132 return; 133 134 trace_hda_unsol_event(bus, res, res_ex); 135 wp = (bus->unsol_wp + 1) % HDA_UNSOL_QUEUE_SIZE; 136 bus->unsol_wp = wp; 137 138 wp <<= 1; 139 bus->unsol_queue[wp] = res; 140 bus->unsol_queue[wp + 1] = res_ex; 141 142 schedule_work(&bus->unsol_work); 143 } 144 EXPORT_SYMBOL_GPL(snd_hdac_bus_queue_event); 145 146 /* 147 * process queued unsolicited events 148 */ 149 void snd_hdac_bus_process_unsol_events(struct work_struct *work) 150 { 151 struct hdac_bus *bus = container_of(work, struct hdac_bus, unsol_work); 152 struct hdac_device *codec; 153 struct hdac_driver *drv; 154 unsigned int rp, caddr, res; 155 156 while (bus->unsol_rp != bus->unsol_wp) { 157 rp = (bus->unsol_rp + 1) % HDA_UNSOL_QUEUE_SIZE; 158 bus->unsol_rp = rp; 159 rp <<= 1; 160 res = bus->unsol_queue[rp]; 161 caddr = bus->unsol_queue[rp + 1]; 162 if (!(caddr & (1 << 4))) /* no unsolicited event? */ 163 continue; 164 codec = bus->caddr_tbl[caddr & 0x0f]; 165 if (!codec || !codec->dev.driver) 166 continue; 167 drv = drv_to_hdac_driver(codec->dev.driver); 168 if (drv->unsol_event) 169 drv->unsol_event(codec, res); 170 } 171 } 172 EXPORT_SYMBOL_GPL(snd_hdac_bus_process_unsol_events); 173 174 /** 175 * snd_hdac_bus_add_device - Add a codec to bus 176 * @bus: HDA core bus 177 * @codec: HDA core device to add 178 * 179 * Adds the given codec to the list in the bus. The caddr_tbl array 180 * and codec_powered bits are updated, as well. 181 * Returns zero if success, or a negative error code. 182 */ 183 int snd_hdac_bus_add_device(struct hdac_bus *bus, struct hdac_device *codec) 184 { 185 if (bus->caddr_tbl[codec->addr]) { 186 dev_err(bus->dev, "address 0x%x is already occupied\n", 187 codec->addr); 188 return -EBUSY; 189 } 190 191 list_add_tail(&codec->list, &bus->codec_list); 192 bus->caddr_tbl[codec->addr] = codec; 193 set_bit(codec->addr, &bus->codec_powered); 194 bus->num_codecs++; 195 return 0; 196 } 197 EXPORT_SYMBOL_GPL(snd_hdac_bus_add_device); 198 199 /** 200 * snd_hdac_bus_remove_device - Remove a codec from bus 201 * @bus: HDA core bus 202 * @codec: HDA core device to remove 203 */ 204 void snd_hdac_bus_remove_device(struct hdac_bus *bus, 205 struct hdac_device *codec) 206 { 207 WARN_ON(bus != codec->bus); 208 if (list_empty(&codec->list)) 209 return; 210 list_del_init(&codec->list); 211 bus->caddr_tbl[codec->addr] = NULL; 212 clear_bit(codec->addr, &bus->codec_powered); 213 bus->num_codecs--; 214 flush_work(&bus->unsol_work); 215 } 216 EXPORT_SYMBOL_GPL(snd_hdac_bus_remove_device); 217