ALSA: usbaudio: parse USB descriptors with structs

In preparation of support for v2.0 audio class, use the structs from
linux/usb/audio.h and add some new ones to describe the fields that are
actually parsed by the descriptor decoders.

Also, factor out code from usb_create_streams(). This makes it easier to
adopt the new iteration logic needed for v2.0.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 28 insertions, 4 deletions

diff --git a/include/linux/usb/audio.h b/include/linux/usb/audio.h
index eaf9dffe0a01..44f82d8e09c5 100644
--- a/include/linux/usb/audio.h
+++ b/include/linux/usb/audio.h
@@ -81,7 +81,7 @@
 
 /* Terminal Control Selectors */
 /* 4.3.2  Class-Specific AC Interface Descriptor */
-struct uac_ac_header_descriptor {
+struct uac_ac_header_descriptor_v1 {
         __u8  bLength;                  /* 8 + n */
         __u8  bDescriptorType;          /* USB_DT_CS_INTERFACE */
         __u8  bDescriptorSubtype;       /* UAC_MS_HEADER */
@@ -95,7 +95,7 @@ struct uac_ac_header_descriptor {
 
 /* As above, but more useful for defining your own descriptors: */
 #define DECLARE_UAC_AC_HEADER_DESCRIPTOR(n)                     \
-struct uac_ac_header_descriptor_##n {                           \
+struct uac_ac_header_descriptor_v1_##n {                        \
         __u8  bLength;                                          \
         __u8  bDescriptorType;                                  \
         __u8  bDescriptorSubtype;                               \
@@ -131,7 +131,7 @@ struct uac_input_terminal_descriptor {
 #define UAC_INPUT_TERMINAL_PROC_MICROPHONE_ARRAY        0x206
 
 /* 4.3.2.2 Output Terminal Descriptor */
-struct uac_output_terminal_descriptor {
+struct uac_output_terminal_descriptor_v1 {
         __u8  bLength;                  /* in bytes: 9 */
         __u8  bDescriptorType;          /* CS_INTERFACE descriptor type */
         __u8  bDescriptorSubtype;       /* OUTPUT_TERMINAL descriptor subtype */
@@ -171,7 +171,7 @@ struct uac_feature_unit_descriptor_##ch {			\
 } __attribute__ ((packed))
 
 /* 4.5.2 Class-Specific AS Interface Descriptor */
-struct uac_as_header_descriptor {
+struct uac_as_header_descriptor_v1 {
         __u8  bLength;                  /* in bytes: 7 */
         __u8  bDescriptorType;          /* USB_DT_CS_INTERFACE */
         __u8  bDescriptorSubtype;       /* AS_GENERAL */
@@ -232,6 +232,19 @@ struct uac_format_type_i_discrete_descriptor_##n {		\
 
 #define UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(n) (8 + (n * 3))
 
+/* Formats - Audio Data Format Type I Codes */
+
+struct uac_format_type_ii_discrete_descriptor {
+        __u8 bLength;
+        __u8 bDescriptorType;
+        __u8 bDescriptorSubtype;
+        __u8 bFormatType;
+        __le16 wMaxBitRate;
+        __le16 wSamplesPerFrame;
+        __u8 bSamFreqType;
+        __u8 tSamFreq[][3];
+} __attribute__((packed));
+
 /* Formats - A.2 Format Type Codes */
 #define UAC_FORMAT_TYPE_UNDEFINED       0x0
 #define UAC_FORMAT_TYPE_I               0x1
@@ -253,6 +266,17 @@ struct uac_iso_endpoint_descriptor {
 #define UAC_EP_CS_ATTR_FILL_MAX         0x80
 
 /* A.10.2 Feature Unit Control Selectors */
+
+struct uac_feature_unit_descriptor {
+        __u8 bLength;
+        __u8 bDescriptorType;
+        __u8 bDescriptorSubtype;
+        __u8 bUnitID;
+        __u8 bSourceID;
+        __u8 bControlSize;
+        __u8 controls[0]; /* variable length */
+} __attribute__((packed));
+
 #define UAC_FU_CONTROL_UNDEFINED        0x00
 #define UAC_MUTE_CONTROL                0x01
 #define UAC_VOLUME_CONTROL              0x02