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