1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * HD-audio core bus driver 4 */ 5 6 #include <linux/init.h> 7 #include <linux/device.h> 8 #include <linux/module.h> 9 #include <linux/export.h> 10 #include <sound/hdaudio.h> 11 #include "trace.h" 12 13 static const struct hdac_bus_ops default_ops = { 14 .command = snd_hdac_bus_send_cmd, 15 .get_response = snd_hdac_bus_get_response, 16 }; 17 18 /** 19 * snd_hdac_bus_init - initialize a HD-audio bas bus 20 * @bus: the pointer to bus object 21 * @ops: bus verb operators 22 * @io_ops: lowlevel I/O operators 23 * 24 * Returns 0 if successful, or a negative error code. 25 */ 26 int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev, 27 const struct hdac_bus_ops *ops, 28 const struct hdac_io_ops *io_ops) 29 { 30 memset(bus, 0, sizeof(*bus)); 31 bus->dev = dev; 32 if (ops) 33 bus->ops = ops; 34 else 35 bus->ops = &default_ops; 36 bus->io_ops = io_ops; 37 INIT_LIST_HEAD(&bus->stream_list); 38 INIT_LIST_HEAD(&bus->codec_list); 39 INIT_WORK(&bus->unsol_work, snd_hdac_bus_process_unsol_events); 40 spin_lock_init(&bus->reg_lock); 41 mutex_init(&bus->cmd_mutex); 42 mutex_init(&bus->lock); 43 INIT_LIST_HEAD(&bus->hlink_list); 44 bus->irq = -1; 45 return 0; 46 } 47 EXPORT_SYMBOL_GPL(snd_hdac_bus_init); 48 49 /** 50 * snd_hdac_bus_exit - clean up a HD-audio bas bus 51 * @bus: the pointer to bus object 52 */ 53 void snd_hdac_bus_exit(struct hdac_bus *bus) 54 { 55 WARN_ON(!list_empty(&bus->stream_list)); 56 WARN_ON(!list_empty(&bus->codec_list)); 57 cancel_work_sync(&bus->unsol_work); 58 } 59 EXPORT_SYMBOL_GPL(snd_hdac_bus_exit); 60 61 /** 62 * snd_hdac_bus_exec_verb - execute a HD-audio verb on the given bus 63 * @bus: bus object 64 * @cmd: HD-audio encoded verb 65 * @res: pointer to store the response, NULL if performing asynchronously 66 * 67 * Returns 0 if successful, or a negative error code. 68 */ 69 int snd_hdac_bus_exec_verb(struct hdac_bus *bus, unsigned int addr, 70 unsigned int cmd, unsigned int *res) 71 { 72 int err; 73 74 mutex_lock(&bus->cmd_mutex); 75 err = snd_hdac_bus_exec_verb_unlocked(bus, addr, cmd, res); 76 mutex_unlock(&bus->cmd_mutex); 77 return err; 78 } 79 EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb); 80 81 /** 82 * snd_hdac_bus_exec_verb_unlocked - unlocked version 83 * @bus: bus object 84 * @cmd: HD-audio encoded verb 85 * @res: pointer to store the response, NULL if performing asynchronously 86 * 87 * Returns 0 if successful, or a negative error code. 88 */ 89 int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr, 90 unsigned int cmd, unsigned int *res) 91 { 92 unsigned int tmp; 93 int err; 94 95 if (cmd == ~0) 96 return -EINVAL; 97 98 if (res) 99 *res = -1; 100 else if (bus->sync_write) 101 res = &tmp; 102 for (;;) { 103 trace_hda_send_cmd(bus, cmd); 104 err = bus->ops->command(bus, cmd); 105 if (err != -EAGAIN) 106 break; 107 /* process pending verbs */ 108 err = bus->ops->get_response(bus, addr, &tmp); 109 if (err) 110 break; 111 } 112 if (!err && res) { 113 err = bus->ops->get_response(bus, addr, res); 114 trace_hda_get_response(bus, addr, *res); 115 } 116 return err; 117 } 118 EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb_unlocked); 119 120 /** 121 * snd_hdac_bus_queue_event - add an unsolicited event to queue 122 * @bus: the BUS 123 * @res: unsolicited event (lower 32bit of RIRB entry) 124 * @res_ex: codec addr and flags (upper 32bit or RIRB entry) 125 * 126 * Adds the given event to the queue. The events are processed in 127 * the workqueue asynchronously. Call this function in the interrupt 128 * hanlder when RIRB receives an unsolicited event. 129 */ 130 void snd_hdac_bus_queue_event(struct hdac_bus *bus, u32 res, u32 res_ex) 131 { 132 unsigned int wp; 133 134 if (!bus) 135 return; 136 137 trace_hda_unsol_event(bus, res, res_ex); 138 wp = (bus->unsol_wp + 1) % HDA_UNSOL_QUEUE_SIZE; 139 bus->unsol_wp = wp; 140 141 wp <<= 1; 142 bus->unsol_queue[wp] = res; 143 bus->unsol_queue[wp + 1] = res_ex; 144 145 schedule_work(&bus->unsol_work); 146 } 147 EXPORT_SYMBOL_GPL(snd_hdac_bus_queue_event); 148 149 /* 150 * process queued unsolicited events 151 */ 152 void snd_hdac_bus_process_unsol_events(struct work_struct *work) 153 { 154 struct hdac_bus *bus = container_of(work, struct hdac_bus, unsol_work); 155 struct hdac_device *codec; 156 struct hdac_driver *drv; 157 unsigned int rp, caddr, res; 158 159 while (bus->unsol_rp != bus->unsol_wp) { 160 rp = (bus->unsol_rp + 1) % HDA_UNSOL_QUEUE_SIZE; 161 bus->unsol_rp = rp; 162 rp <<= 1; 163 res = bus->unsol_queue[rp]; 164 caddr = bus->unsol_queue[rp + 1]; 165 if (!(caddr & (1 << 4))) /* no unsolicited event? */ 166 continue; 167 codec = bus->caddr_tbl[caddr & 0x0f]; 168 if (!codec || !codec->dev.driver) 169 continue; 170 drv = drv_to_hdac_driver(codec->dev.driver); 171 if (drv->unsol_event) 172 drv->unsol_event(codec, res); 173 } 174 } 175 EXPORT_SYMBOL_GPL(snd_hdac_bus_process_unsol_events); 176 177 /** 178 * snd_hdac_bus_add_device - Add a codec to bus 179 * @bus: HDA core bus 180 * @codec: HDA core device to add 181 * 182 * Adds the given codec to the list in the bus. The caddr_tbl array 183 * and codec_powered bits are updated, as well. 184 * Returns zero if success, or a negative error code. 185 */ 186 int snd_hdac_bus_add_device(struct hdac_bus *bus, struct hdac_device *codec) 187 { 188 if (bus->caddr_tbl[codec->addr]) { 189 dev_err(bus->dev, "address 0x%x is already occupied\n", 190 codec->addr); 191 return -EBUSY; 192 } 193 194 list_add_tail(&codec->list, &bus->codec_list); 195 bus->caddr_tbl[codec->addr] = codec; 196 set_bit(codec->addr, &bus->codec_powered); 197 bus->num_codecs++; 198 return 0; 199 } 200 EXPORT_SYMBOL_GPL(snd_hdac_bus_add_device); 201 202 /** 203 * snd_hdac_bus_remove_device - Remove a codec from bus 204 * @bus: HDA core bus 205 * @codec: HDA core device to remove 206 */ 207 void snd_hdac_bus_remove_device(struct hdac_bus *bus, 208 struct hdac_device *codec) 209 { 210 WARN_ON(bus != codec->bus); 211 if (list_empty(&codec->list)) 212 return; 213 list_del_init(&codec->list); 214 bus->caddr_tbl[codec->addr] = NULL; 215 clear_bit(codec->addr, &bus->codec_powered); 216 bus->num_codecs--; 217 flush_work(&bus->unsol_work); 218 } 219 EXPORT_SYMBOL_GPL(snd_hdac_bus_remove_device); 220