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-rw-r--r--sound/hda/hdac_bus.c181
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);