Commit 446fa3a9 authored Feb 05, 2016 by John Youn Committed by Felipe Balbi Mar 04, 2016

usb: ch9: Add size macro for SSP dev cap descriptor



The SuperspeedPlus Device Capability Descriptor has a variable size
depending on the number of sublink speed attributes.

This patch adds a macro to calculate that size. The macro takes one
argument, the Sublink Speed Attribute Count (SSAC) as reported by the
descriptor in bmAttributes[4:0].

See USB 3.1 9.6.2.5, Table 9-19.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

parent 7b05d3b3

include/uapi/linux/usb/ch9.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -923,6 +923,12 @@ struct usb_ptm_cap_descriptor {
		__u8 bDevCapabilityType;
		} __attribute__((packed));

		/*
		* The size of the descriptor for the Sublink Speed Attribute Count
		* (SSAC) specified in bmAttributes[4:0].
		*/
		#define USB_DT_USB_SSP_CAP_SIZE(ssac) (16 + ssac * 4)

		/-------------------------------------------------------------------------/

		/* USB_DT_WIRELESS_ENDPOINT_COMP: companion descriptor associated with