[PATCH v3 1/4] usb: audio-v2: add ability to define feature unit descriptor
From: Pavel Hofman <hidden>
Date: 2021-07-12 12:55:39
Subsystem:
the rest, usb subsystem · Maintainers:
Linus Torvalds, Greg Kroah-Hartman
From: Ruslan Bilovol <redacted> Similar to UAC1 spec, UAC2 feature unit descriptor has variable size. Current audio-v2 feature unit descriptor structure is used for parsing descriptors, but can't be used to define your own descriptor. Add a new macro similar to what audio v1 already has. Signed-off-by: Ruslan Bilovol <redacted> Signed-off-by: Pavel Hofman <redacted> --- include/linux/usb/audio-v2.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/include/linux/usb/audio-v2.h b/include/linux/usb/audio-v2.h
index ead8c9a47c6a..8fc2abd7aecb 100644
--- a/include/linux/usb/audio-v2.h
+++ b/include/linux/usb/audio-v2.h@@ -156,6 +156,20 @@ struct uac2_feature_unit_descriptor { __u8 bmaControls[]; /* variable length */ } __attribute__((packed)); +#define UAC2_DT_FEATURE_UNIT_SIZE(ch) (6 + ((ch) + 1) * 4) + +/* As above, but more useful for defining your own descriptors: */ +#define DECLARE_UAC2_FEATURE_UNIT_DESCRIPTOR(ch) \ +struct uac2_feature_unit_descriptor_##ch { \ + __u8 bLength; \ + __u8 bDescriptorType; \ + __u8 bDescriptorSubtype; \ + __u8 bUnitID; \ + __u8 bSourceID; \ + __le32 bmaControls[ch + 1]; \ + __u8 iFeature; \ +} __packed + /* 4.7.2.10 Effect Unit Descriptor */ struct uac2_effect_unit_descriptor {
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2.25.1