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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH v2 3/3] sndif: Add explicit back and front parameter negotiation
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
In order to provide explicit stream parameter negotiation between
backend and frontend the following changes are introduced in the protocol:
add XENSND_OP_HW_PARAM_QUERY request to read/update
configuration space for the parameter given: request passes
desired parameter interval (mask) and the response to this request
returns min/max interval (mask) for the parameter to be used.
Parameters supported by this request/response:
- format mask
- sample rate interval
- number of channels interval
- buffer size, interval, frames
- period size, interval, frames
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Cc: Takashi Iwai <tiwai@xxxxxxx>
---
xen/include/public/io/sndif.h | 124 +++++++++++++++++++++++++++++++++++++++---
1 file changed, 117 insertions(+), 7 deletions(-)
diff --git a/xen/include/public/io/sndif.h b/xen/include/public/io/sndif.h
index 1a6a1467f253..ff0ba15b0462 100644
--- a/xen/include/public/io/sndif.h
+++ b/xen/include/public/io/sndif.h
@@ -465,12 +465,19 @@
#define XENSND_OP_MUTE 6
#define XENSND_OP_UNMUTE 7
#define XENSND_OP_TRIGGER 8
+#define XENSND_OP_HW_PARAM_QUERY 9
#define XENSND_OP_TRIGGER_START 0
#define XENSND_OP_TRIGGER_PAUSE 1
#define XENSND_OP_TRIGGER_STOP 2
#define XENSND_OP_TRIGGER_RESUME 3
+#define XENSND_OP_HW_PARAM_FORMAT 0
+#define XENSND_OP_HW_PARAM_RATE 1
+#define XENSND_OP_HW_PARAM_BUFFER 2
+#define XENSND_OP_HW_PARAM_PERIOD 3
+#define XENSND_OP_HW_PARAM_CHANNELS 4
+
/*
******************************************************************************
* EVENT CODES
@@ -828,28 +835,127 @@ struct xensnd_trigger_req {
};
/*
+ * Request stream configuration parameter range: request interval or
+ * bit mask of the supported values for the parameter given.
+ *
+ * Sound device configuration for a particular stream is a limited subset
+ * of the multidimensional configuration available on XenStore, for instance,
+ * once frame rate has been selected there is a limited supported range
+ * for sample rates becomes available (which might be the same set configured
+ * on XenStore or less). For example, selecting 96kHz sample rate may limit
+ * number of channels available for such configuration from 4 to 2 etc.
+ * Thus, each call to XENSND_OP_HW_PARAM_QUERY will reduce configuration
+ * space making it possible to iteratively get the final stream
configuration,
+ * used in XENSND_OP_OPEN request.
+ *
+ * See response format for this request.
+ *
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | _HW_PARAM_QUERY| reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | param | reserved | 12
+ * +----------------+----------------+----------------+----------------+
+ * | min or mask low 32-bit | 16
+ * +----------------+----------------+----------------+----------------+
+ * | max or mask high 32-bit | 20
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 24
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 28
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 32
+ * +----------------+----------------+----------------+----------------+
+ *
+ * param - uint8_t, XENSND_OP_HW_PARAM_XXX value
+ *
+ * The following parameters' payload treated as interval:
+ * XENSND_OP_HW_PARAM_RATE
+ * XENSND_OP_HW_PARAM_BUFFER
+ * XENSND_OP_HW_PARAM_PERIOD
+ * XENSND_OP_HW_PARAM_CHANNELS
+ *
+ * For interval parameters the payload of the request:
+ * min - uint32_t, minimum value of the parameter
+ * max - uint32_t, maximum value of the parameter
+ *
+ * For the following parameters their min and max values are expressed in
+ * frames:
+ * XENSND_OP_HW_PARAM_BUFFER
+ * XENSND_OP_HW_PARAM_PERIOD
+ * where frame is defined as a product of the number of channels by the
+ * number of octets per one sample.
+ *
+ * The following parameters' payload treated as a bit mask:
+ * XENSND_OP_HW_PARAM_FORMAT
+ *
+ * For mask parameters the payload of the request:
+ * mask - uint64_t, bit mask representing values of the parameter
+ */
+
+struct xensnd_query_hw_param_req {
+ uint8_t param;
+ uint8_t reserved[3];
+ union {
+ struct {
+ uint32_t min;
+ uint32_t max;
+ } interval;
+ uint64_t mask;
+ } val;
+};
+
+/*
*---------------------------------- Responses --------------------------------
*
* All response packets have the same length (32 octets)
*
- * Response for all requests:
+ * All response packets have common header:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | status | 8
+ * +----------------+----------------+----------------+----------------+
+ *
+ * id - uint16_t, copied from the request
+ * operation - uint8_t, XENSND_OP_* - copied from request
+ * status - int32_t, response status, zero on success and -XEN_EXX on failure
+ *
+ *
+ * HW parameter query response - response for XENSND_OP_HW_PARAM_QUERY:
* 0 1 2 3 octet
* +----------------+----------------+----------------+----------------+
* | id | operation | reserved | 4
* +----------------+----------------+----------------+----------------+
* | status | 8
* +----------------+----------------+----------------+----------------+
- * | reserved | 12
+ * | min or mask low 32-bit | 12
+ * +----------------+----------------+----------------+----------------+
+ * | max or mask high 32-bit | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
* +----------------+----------------+----------------+----------------+
* |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
* +----------------+----------------+----------------+----------------+
* | reserved | 32
* +----------------+----------------+----------------+----------------+
*
- * id - uint16_t, copied from the request
- * operation - uint8_t, XENSND_OP_* - copied from request
- * status - int32_t, response status, zero on success and -XEN_EXX on failure
- *
+ * The payload meaning is the same as in the corresponing HW parameter
+ * request: see XENSND_OP_HW_PARAM_QUERY for details.
+ */
+
+union xensnd_query_hw_param_resp {
+ struct {
+ uint32_t min;
+ uint32_t max;
+ } interval;
+ uint64_t mask;
+};
+
+/*
*----------------------------------- Events ----------------------------------
*
* Events are sent via a shared page allocated by the front and propagated by
@@ -902,6 +1008,7 @@ struct xensnd_req {
struct xensnd_open_req open;
struct xensnd_rw_req rw;
struct xensnd_trigger_req trigger;
+ struct xensnd_query_hw_param_req hw_param;
uint8_t reserved[24];
} op;
};
@@ -911,7 +1018,10 @@ struct xensnd_resp {
uint8_t operation;
uint8_t reserved;
int32_t status;
- uint8_t reserved1[24];
+ union {
+ union xensnd_query_hw_param_resp hw_param;
+ uint8_t reserved1[24];
+ } resp;
};
struct xensnd_evt {
--
2.7.4
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