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@@ -36,6 +36,13 @@
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#include "ring.h"
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#include "../grant_table.h"
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+/*
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+ ******************************************************************************
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+ * Protocol version
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+ ******************************************************************************
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+ */
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+#define XENSND_PROTOCOL_VERSION 2
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+
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/*
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******************************************************************************
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* Feature and Parameter Negotiation
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@@ -106,6 +113,8 @@
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*
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* /local/domain/1/device/vsnd/0/0/0/ring-ref = "386"
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* /local/domain/1/device/vsnd/0/0/0/event-channel = "15"
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+ * /local/domain/1/device/vsnd/0/0/0/evt-ring-ref = "1386"
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+ * /local/domain/1/device/vsnd/0/0/0/evt-event-channel = "215"
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*
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*------------------------------ Stream 1, capture ----------------------------
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*
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@@ -115,6 +124,8 @@
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*
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* /local/domain/1/device/vsnd/0/0/1/ring-ref = "384"
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* /local/domain/1/device/vsnd/0/0/1/event-channel = "13"
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+ * /local/domain/1/device/vsnd/0/0/1/evt-ring-ref = "1384"
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+ * /local/domain/1/device/vsnd/0/0/1/evt-event-channel = "213"
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*
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*------------------------------- PCM device 1 --------------------------------
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*
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@@ -128,6 +139,8 @@
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*
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* /local/domain/1/device/vsnd/0/1/0/ring-ref = "387"
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* /local/domain/1/device/vsnd/0/1/0/event-channel = "151"
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+ * /local/domain/1/device/vsnd/0/1/0/evt-ring-ref = "1387"
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+ * /local/domain/1/device/vsnd/0/1/0/evt-event-channel = "351"
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*
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*------------------------------- PCM device 2 --------------------------------
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*
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@@ -140,6 +153,8 @@
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*
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* /local/domain/1/device/vsnd/0/2/0/ring-ref = "389"
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* /local/domain/1/device/vsnd/0/2/0/event-channel = "152"
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+ * /local/domain/1/device/vsnd/0/2/0/evt-ring-ref = "1389"
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+ * /local/domain/1/device/vsnd/0/2/0/evt-event-channel = "452"
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*
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******************************************************************************
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* Backend XenBus Nodes
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@@ -285,6 +300,23 @@
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* The Xen grant reference granting permission for the backend to map
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* a sole page in a single page sized ring buffer.
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*
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+ *--------------------- Stream Event Transport Parameters ---------------------
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+ *
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+ * This communication path is used to deliver asynchronous events from backend
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+ * to frontend, set up per stream.
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+ *
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+ * evt-event-channel
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+ * Values: <uint32_t>
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+ *
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+ * The identifier of the Xen event channel used to signal activity
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+ * in the ring buffer.
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+ *
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+ * evt-ring-ref
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+ * Values: <uint32_t>
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+ *
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+ * The Xen grant reference granting permission for the backend to map
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+ * a sole page in a single page sized ring buffer.
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+ *
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******************************************************************************
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* STATE DIAGRAMS
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******************************************************************************
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@@ -432,6 +464,20 @@
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#define XENSND_OP_GET_VOLUME 5
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#define XENSND_OP_MUTE 6
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#define XENSND_OP_UNMUTE 7
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+#define XENSND_OP_TRIGGER 8
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+#define XENSND_OP_HW_PARAM_QUERY 9
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+
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+#define XENSND_OP_TRIGGER_START 0
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+#define XENSND_OP_TRIGGER_PAUSE 1
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+#define XENSND_OP_TRIGGER_STOP 2
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+#define XENSND_OP_TRIGGER_RESUME 3
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+
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+/*
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+ ******************************************************************************
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+ * EVENT CODES
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+ ******************************************************************************
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+ */
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+#define XENSND_EVT_CUR_POS 0
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/*
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******************************************************************************
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@@ -448,6 +494,8 @@
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#define XENSND_FIELD_VCARD_LONG_NAME "long-name"
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#define XENSND_FIELD_RING_REF "ring-ref"
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#define XENSND_FIELD_EVT_CHNL "event-channel"
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+#define XENSND_FIELD_EVT_RING_REF "evt-ring-ref"
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+#define XENSND_FIELD_EVT_EVT_CHNL "evt-event-channel"
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#define XENSND_FIELD_DEVICE_NAME "name"
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#define XENSND_FIELD_TYPE "type"
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#define XENSND_FIELD_STREAM_UNIQUE_ID "unique-id"
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@@ -526,7 +574,7 @@
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*
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*---------------------------------- Requests ---------------------------------
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*
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- * All request packets have the same length (32 octets)
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+ * All request packets have the same length (64 octets)
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* All request packets have common header:
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* 0 1 2 3 octet
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* +----------------+----------------+----------------+----------------+
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@@ -559,11 +607,13 @@
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* +----------------+----------------+----------------+----------------+
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* | gref_directory | 24
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 28
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+ * | period_sz | 28
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 32
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* +----------------+----------------+----------------+----------------+
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* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 32
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+ * | reserved | 64
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* +----------------+----------------+----------------+----------------+
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*
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* pcm_rate - uint32_t, stream data rate, Hz
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@@ -571,6 +621,14 @@
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* pcm_channels - uint8_t, number of channels of this stream,
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* [channels-min; channels-max]
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* buffer_sz - uint32_t, buffer size to be allocated, octets
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+ * period_sz - uint32_t, event period size, octets
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+ * This is the requested value of the period at which frontend would
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+ * like to receive XENSND_EVT_CUR_POS notifications from the backend when
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+ * stream position advances during playback/capture.
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+ * It shows how many octets are expected to be played/captured before
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+ * sending such an event.
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+ * If set to 0 no XENSND_EVT_CUR_POS events are sent by the backend.
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+ *
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* gref_directory - grant_ref_t, a reference to the first shared page
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* describing shared buffer references. At least one page exists. If shared
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* buffer size (buffer_sz) exceeds what can be addressed by this single page,
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@@ -585,6 +643,7 @@ struct xensnd_open_req {
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uint16_t reserved;
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uint32_t buffer_sz;
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grant_ref_t gref_directory;
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+ uint32_t period_sz;
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};
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/*
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@@ -632,7 +691,7 @@ struct xensnd_page_directory {
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* +----------------+----------------+----------------+----------------+
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* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 32
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+ * | reserved | 64
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* +----------------+----------------+----------------+----------------+
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*
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* Request read/write - used for read (for capture) or write (for playback):
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@@ -650,7 +709,7 @@ struct xensnd_page_directory {
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* +----------------+----------------+----------------+----------------+
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* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 32
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+ * | reserved | 64
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* +----------------+----------------+----------------+----------------+
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*
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* operation - XENSND_OP_READ for read or XENSND_OP_WRITE for write
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@@ -673,9 +732,11 @@ struct xensnd_rw_req {
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* +----------------+----------------+----------------+----------------+
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* | length | 16
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* +----------------+----------------+----------------+----------------+
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+ * | reserved | 20
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+ * +----------------+----------------+----------------+----------------+
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* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 32
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+ * | reserved | 64
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* +----------------+----------------+----------------+----------------+
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*
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* operation - XENSND_OP_SET_VOLUME for volume set
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@@ -713,9 +774,11 @@ struct xensnd_rw_req {
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* +----------------+----------------+----------------+----------------+
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* | length | 16
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* +----------------+----------------+----------------+----------------+
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+ * | reserved | 20
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+ * +----------------+----------------+----------------+----------------+
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* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 32
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+ * | reserved | 64
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* +----------------+----------------+----------------+----------------+
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*
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* operation - XENSND_OP_MUTE for mute or XENSND_OP_UNMUTE for unmute
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@@ -743,32 +806,213 @@ struct xensnd_rw_req {
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*
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* The 'struct xensnd_rw_req' is also used for XENSND_OP_SET_VOLUME,
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* XENSND_OP_GET_VOLUME, XENSND_OP_MUTE, XENSND_OP_UNMUTE.
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+ *
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+ * Request stream running state change - trigger PCM stream running state
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+ * to start, stop, pause or resume:
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+ *
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+ * 0 1 2 3 octet
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+ * +----------------+----------------+----------------+----------------+
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+ * | id | _OP_TRIGGER | reserved | 4
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 8
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+ * +----------------+----------------+----------------+----------------+
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+ * | type | reserved | 12
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 16
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+ * +----------------+----------------+----------------+----------------+
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+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 64
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+ * +----------------+----------------+----------------+----------------+
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+ *
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+ * type - uint8_t, XENSND_OP_TRIGGER_XXX value
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*/
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+struct xensnd_trigger_req {
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+ uint8_t type;
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+};
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+
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/*
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- *---------------------------------- Responses --------------------------------
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+ * Request stream parameter ranges: request intervals and
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+ * masks of supported ranges for stream configuration values.
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*
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- * All response packets have the same length (32 octets)
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+ * Sound device configuration for a particular stream is a limited subset
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+ * of the multidimensional configuration available on XenStore, e.g.
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+ * once the frame rate has been selected there is a limited supported range
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+ * for sample rates becomes available (which might be the same set configured
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+ * on XenStore or less). For example, selecting 96kHz sample rate may limit
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+ * number of channels available for such configuration from 4 to 2, etc.
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+ * Thus, each call to XENSND_OP_HW_PARAM_QUERY may reduce configuration
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+ * space making it possible to iteratively get the final stream configuration,
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+ * used in XENSND_OP_OPEN request.
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+ *
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+ * See response format for this request.
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*
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- * Response for all requests:
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* 0 1 2 3 octet
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* +----------------+----------------+----------------+----------------+
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- * | id | operation | reserved | 4
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+ * | id | _HW_PARAM_QUERY| reserved | 4
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* +----------------+----------------+----------------+----------------+
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- * | status | 8
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+ * | reserved | 8
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+ * +----------------+----------------+----------------+----------------+
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+ * | formats mask low 32-bit | 12
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+ * +----------------+----------------+----------------+----------------+
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+ * | formats mask high 32-bit | 16
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 12
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+ * | min rate | 20
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+ * +----------------+----------------+----------------+----------------+
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+ * | max rate | 24
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+ * +----------------+----------------+----------------+----------------+
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+ * | min channels | 28
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+ * +----------------+----------------+----------------+----------------+
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+ * | max channels | 32
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+ * +----------------+----------------+----------------+----------------+
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+ * | min buffer frames | 36
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+ * +----------------+----------------+----------------+----------------+
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+ * | max buffer frames | 40
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+ * +----------------+----------------+----------------+----------------+
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+ * | min period frames | 44
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+ * +----------------+----------------+----------------+----------------+
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+ * | max period frames | 48
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 52
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* +----------------+----------------+----------------+----------------+
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* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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* +----------------+----------------+----------------+----------------+
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- * | reserved | 32
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+ * | reserved | 64
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+ * +----------------+----------------+----------------+----------------+
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+ *
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+ * formats - uint64_t, bit mask representing values of the parameter
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+ * made as bitwise OR of (1 << XENSND_PCM_FORMAT_XXX) values
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+ *
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+ * For interval parameters:
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+ * min - uint32_t, minimum value of the parameter
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+ * max - uint32_t, maximum value of the parameter
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+ *
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+ * Frame is defined as a product of the number of channels by the
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+ * number of octets per one sample.
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+ */
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+
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+struct xensnd_query_hw_param {
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+ uint64_t formats;
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+ struct {
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+ uint32_t min;
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+ uint32_t max;
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+ } rates;
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+ struct {
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+ uint32_t min;
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+ uint32_t max;
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+ } channels;
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+ struct {
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+ uint32_t min;
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+ uint32_t max;
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+ } buffer;
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+ struct {
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+ uint32_t min;
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+ uint32_t max;
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+ } period;
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+};
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+
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+/*
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+ *---------------------------------- Responses --------------------------------
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+ *
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+ * All response packets have the same length (64 octets)
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+ *
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+ * All response packets have common header:
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+ * 0 1 2 3 octet
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+ * +----------------+----------------+----------------+----------------+
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+ * | id | operation | reserved | 4
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+ * +----------------+----------------+----------------+----------------+
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+ * | status | 8
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* +----------------+----------------+----------------+----------------+
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*
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* id - uint16_t, copied from the request
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* operation - uint8_t, XENSND_OP_* - copied from request
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* status - int32_t, response status, zero on success and -XEN_EXX on failure
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+ *
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+ *
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+ * HW parameter query response - response for XENSND_OP_HW_PARAM_QUERY:
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+ * 0 1 2 3 octet
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+ * +----------------+----------------+----------------+----------------+
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+ * | id | operation | reserved | 4
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+ * +----------------+----------------+----------------+----------------+
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+ * | status | 8
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+ * +----------------+----------------+----------------+----------------+
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+ * | formats mask low 32-bit | 12
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+ * +----------------+----------------+----------------+----------------+
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+ * | formats mask high 32-bit | 16
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+ * +----------------+----------------+----------------+----------------+
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+ * | min rate | 20
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+ * +----------------+----------------+----------------+----------------+
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+ * | max rate | 24
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+ * +----------------+----------------+----------------+----------------+
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+ * | min channels | 28
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+ * +----------------+----------------+----------------+----------------+
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+ * | max channels | 32
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+ * +----------------+----------------+----------------+----------------+
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+ * | min buffer frames | 36
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+ * +----------------+----------------+----------------+----------------+
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+ * | max buffer frames | 40
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+ * +----------------+----------------+----------------+----------------+
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+ * | min period frames | 44
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+ * +----------------+----------------+----------------+----------------+
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+ * | max period frames | 48
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 52
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+ * +----------------+----------------+----------------+----------------+
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+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 64
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+ * +----------------+----------------+----------------+----------------+
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+ *
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+ * Meaning of the values in this response is the same as for
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+ * XENSND_OP_HW_PARAM_QUERY request.
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+ */
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+
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+/*
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+ *----------------------------------- Events ----------------------------------
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+ *
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+ * Events are sent via shared page allocated by the front and propagated by
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+ * evt-event-channel/evt-ring-ref XenStore entries
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+ * All event packets have the same length (64 octets)
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+ * All event packets have common header:
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+ * 0 1 2 3 octet
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+ * +----------------+----------------+----------------+----------------+
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+ * | id | type | reserved | 4
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+ * +----------------+----------------+----------------+----------------+
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+ * | reserved | 8
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+ * +----------------+----------------+----------------+----------------+
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+ *
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+ * id - uint16_t, event id, may be used by front
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+ * type - uint8_t, type of the event
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+ *
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+ *
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+ * Current stream position - event from back to front when stream's
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+ * playback/capture position has advanced:
|
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|
+ * 0 1 2 3 octet
|
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|
+ * +----------------+----------------+----------------+----------------+
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|
|
+ * | id | _EVT_CUR_POS | reserved | 4
|
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|
+ * +----------------+----------------+----------------+----------------+
|
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|
+ * | reserved | 8
|
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|
+ * +----------------+----------------+----------------+----------------+
|
|
|
+ * | position low 32-bit | 12
|
|
|
+ * +----------------+----------------+----------------+----------------+
|
|
|
+ * | position high 32-bit | 16
|
|
|
+ * +----------------+----------------+----------------+----------------+
|
|
|
+ * | reserved | 20
|
|
|
+ * +----------------+----------------+----------------+----------------+
|
|
|
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
|
|
|
+ * +----------------+----------------+----------------+----------------+
|
|
|
+ * | reserved | 64
|
|
|
+ * +----------------+----------------+----------------+----------------+
|
|
|
+ *
|
|
|
+ * position - current value of stream's playback/capture position, octets
|
|
|
+ *
|
|
|
*/
|
|
|
|
|
|
+struct xensnd_cur_pos_evt {
|
|
|
+ uint64_t position;
|
|
|
+};
|
|
|
+
|
|
|
struct xensnd_req {
|
|
|
uint16_t id;
|
|
|
uint8_t operation;
|
|
@@ -776,7 +1020,9 @@ struct xensnd_req {
|
|
|
union {
|
|
|
struct xensnd_open_req open;
|
|
|
struct xensnd_rw_req rw;
|
|
|
- uint8_t reserved[24];
|
|
|
+ struct xensnd_trigger_req trigger;
|
|
|
+ struct xensnd_query_hw_param hw_param;
|
|
|
+ uint8_t reserved[56];
|
|
|
} op;
|
|
|
};
|
|
|
|
|
@@ -785,9 +1031,53 @@ struct xensnd_resp {
|
|
|
uint8_t operation;
|
|
|
uint8_t reserved;
|
|
|
int32_t status;
|
|
|
- uint8_t reserved1[24];
|
|
|
+ union {
|
|
|
+ struct xensnd_query_hw_param hw_param;
|
|
|
+ uint8_t reserved1[56];
|
|
|
+ } resp;
|
|
|
+};
|
|
|
+
|
|
|
+struct xensnd_evt {
|
|
|
+ uint16_t id;
|
|
|
+ uint8_t type;
|
|
|
+ uint8_t reserved[5];
|
|
|
+ union {
|
|
|
+ struct xensnd_cur_pos_evt cur_pos;
|
|
|
+ uint8_t reserved[56];
|
|
|
+ } op;
|
|
|
};
|
|
|
|
|
|
DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_resp);
|
|
|
|
|
|
+/*
|
|
|
+ ******************************************************************************
|
|
|
+ * Back to front events delivery
|
|
|
+ ******************************************************************************
|
|
|
+ * In order to deliver asynchronous events from back to front a shared page is
|
|
|
+ * allocated by front and its granted reference propagated to back via
|
|
|
+ * XenStore entries (evt-ring-ref/evt-event-channel).
|
|
|
+ * This page has a common header used by both front and back to synchronize
|
|
|
+ * access and control event's ring buffer, while back being a producer of the
|
|
|
+ * events and front being a consumer. The rest of the page after the header
|
|
|
+ * is used for event packets.
|
|
|
+ *
|
|
|
+ * Upon reception of an event(s) front may confirm its reception
|
|
|
+ * for either each event, group of events or none.
|
|
|
+ */
|
|
|
+
|
|
|
+struct xensnd_event_page {
|
|
|
+ uint32_t in_cons;
|
|
|
+ uint32_t in_prod;
|
|
|
+ uint8_t reserved[56];
|
|
|
+};
|
|
|
+
|
|
|
+#define XENSND_EVENT_PAGE_SIZE XEN_PAGE_SIZE
|
|
|
+#define XENSND_IN_RING_OFFS (sizeof(struct xensnd_event_page))
|
|
|
+#define XENSND_IN_RING_SIZE (XENSND_EVENT_PAGE_SIZE - XENSND_IN_RING_OFFS)
|
|
|
+#define XENSND_IN_RING_LEN (XENSND_IN_RING_SIZE / sizeof(struct xensnd_evt))
|
|
|
+#define XENSND_IN_RING(page) \
|
|
|
+ ((struct xensnd_evt *)((char *)(page) + XENSND_IN_RING_OFFS))
|
|
|
+#define XENSND_IN_RING_REF(page, idx) \
|
|
|
+ (XENSND_IN_RING((page))[(idx) % XENSND_IN_RING_LEN])
|
|
|
+
|
|
|
#endif /* __XEN_PUBLIC_IO_SNDIF_H__ */
|