diff options
Diffstat (limited to 'sound/hda/hdac_bus.c')
| -rw-r--r-- | sound/hda/hdac_bus.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/sound/hda/hdac_bus.c b/sound/hda/hdac_bus.c new file mode 100644 index 000000000000..364f64c0e4a3 --- /dev/null +++ b/sound/hda/hdac_bus.c @@ -0,0 +1,181 @@ +/* + * HD-audio core bus driver + */ + +#include <linux/init.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/export.h> +#include <sound/hdaudio.h> + +static void process_unsol_events(struct work_struct *work); + +/** + * snd_hdac_bus_init - initialize a HD-audio bas bus + * @bus: the pointer to bus object + * + * Returns 0 if successful, or a negative error code. + */ +int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev, + const struct hdac_bus_ops *ops) +{ + memset(bus, 0, sizeof(*bus)); + bus->dev = dev; + bus->ops = ops; + INIT_LIST_HEAD(&bus->codec_list); + INIT_WORK(&bus->unsol_work, process_unsol_events); + mutex_init(&bus->cmd_mutex); + return 0; +} +EXPORT_SYMBOL_GPL(snd_hdac_bus_init); + +/** + * snd_hdac_bus_exit - clean up a HD-audio bas bus + * @bus: the pointer to bus object + */ +void snd_hdac_bus_exit(struct hdac_bus *bus) +{ + WARN_ON(!list_empty(&bus->codec_list)); + cancel_work_sync(&bus->unsol_work); +} +EXPORT_SYMBOL_GPL(snd_hdac_bus_exit); + +/** + * snd_hdac_bus_exec_verb - execute a HD-audio verb on the given bus + * @bus: bus object + * @cmd: HD-audio encoded verb + * @res: pointer to store the response, NULL if performing asynchronously + * + * Returns 0 if successful, or a negative error code. + */ +int snd_hdac_bus_exec_verb(struct hdac_bus *bus, unsigned int addr, + unsigned int cmd, unsigned int *res) +{ + int err; + + mutex_lock(&bus->cmd_mutex); + err = snd_hdac_bus_exec_verb_unlocked(bus, addr, cmd, res); + mutex_unlock(&bus->cmd_mutex); + return err; +} +EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb); + +/** + * snd_hdac_bus_exec_verb_unlocked - unlocked version + * @bus: bus object + * @cmd: HD-audio encoded verb + * @res: pointer to store the response, NULL if performing asynchronously + * + * Returns 0 if successful, or a negative error code. + */ +int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr, + unsigned int cmd, unsigned int *res) +{ + unsigned int tmp; + int err; + + if (cmd == ~0) + return -EINVAL; + + if (res) + *res = -1; + else if (bus->sync_write) + res = &tmp; + for (;;) { + err = bus->ops->command(bus, cmd); + if (err != -EAGAIN) + break; + /* process pending verbs */ + err = bus->ops->get_response(bus, addr, &tmp); + if (err) + break; + } + if (!err && res) + err = bus->ops->get_response(bus, addr, res); + return err; +} +EXPORT_SYMBOL_GPL(snd_hdac_bus_exec_verb_unlocked); + +/** + * snd_hdac_bus_queue_event - add an unsolicited event to queue + * @bus: the BUS + * @res: unsolicited event (lower 32bit of RIRB entry) + * @res_ex: codec addr and flags (upper 32bit or RIRB entry) + * + * Adds the given event to the queue. The events are processed in + * the workqueue asynchronously. Call this function in the interrupt + * hanlder when RIRB receives an unsolicited event. + */ +void snd_hdac_bus_queue_event(struct hdac_bus *bus, u32 res, u32 res_ex) +{ + unsigned int wp; + + if (!bus) + return; + + wp = (bus->unsol_wp + 1) % HDA_UNSOL_QUEUE_SIZE; + bus->unsol_wp = wp; + + wp <<= 1; + bus->unsol_queue[wp] = res; + bus->unsol_queue[wp + 1] = res_ex; + + schedule_work(&bus->unsol_work); +} +EXPORT_SYMBOL_GPL(snd_hdac_bus_queue_event); + +/* + * process queued unsolicited events + */ +static void process_unsol_events(struct work_struct *work) +{ + struct hdac_bus *bus = container_of(work, struct hdac_bus, unsol_work); + struct hdac_device *codec; + struct hdac_driver *drv; + unsigned int rp, caddr, res; + + while (bus->unsol_rp != bus->unsol_wp) { + rp = (bus->unsol_rp + 1) % HDA_UNSOL_QUEUE_SIZE; + bus->unsol_rp = rp; + rp <<= 1; + res = bus->unsol_queue[rp]; + caddr = bus->unsol_queue[rp + 1]; + if (!(caddr & (1 << 4))) /* no unsolicited event? */ + continue; + codec = bus->caddr_tbl[caddr & 0x0f]; + if (!codec || !codec->dev.driver) + continue; + drv = drv_to_hdac_driver(codec->dev.driver); + if (drv->unsol_event) + drv->unsol_event(codec, res); + } +} + +int snd_hdac_bus_add_device(struct hdac_bus *bus, struct hdac_device *codec) +{ + if (bus->caddr_tbl[codec->addr]) { + dev_err(bus->dev, "address 0x%x is already occupied\n", + codec->addr); + return -EBUSY; + } + + list_add_tail(&codec->list, &bus->codec_list); + bus->caddr_tbl[codec->addr] = codec; + set_bit(codec->addr, &bus->codec_powered); + bus->num_codecs++; + return 0; +} +EXPORT_SYMBOL_GPL(snd_hdac_bus_add_device); + +void snd_hdac_bus_remove_device(struct hdac_bus *bus, + struct hdac_device *codec) +{ + WARN_ON(bus != codec->bus); + if (list_empty(&codec->list)) + return; + list_del_init(&codec->list); + bus->caddr_tbl[codec->addr] = NULL; + clear_bit(codec->addr, &bus->codec_powered); + bus->num_codecs--; +} +EXPORT_SYMBOL_GPL(snd_hdac_bus_remove_device); |