diff options
| author | John Youn <John.Youn@synopsys.com> | 2016-02-05 17:05:12 -0800 |
|---|---|---|
| committer | Felipe Balbi <balbi@kernel.org> | 2016-03-04 15:14:22 +0200 |
| commit | 446fa3a95df1e8b78f25e1babc41e46edd200821 (patch) | |
| tree | 0e5d8aad4c5c142907309bd7fa827d5d65ba273f /include/uapi | |
| parent | 7b05d3b37437f8d50a75545a0fd56ee585c58821 (diff) | |
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>
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/linux/usb/ch9.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h index 252ac16635dc..28bee8d44735 100644 --- a/include/uapi/linux/usb/ch9.h +++ b/include/uapi/linux/usb/ch9.h @@ -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 |