[PATCH 4.4 44/49] usb: ch9: Add size macro for SSP dev cap descriptor

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: John Youn <John.Youn@xxxxxxxxxxxx>

commit 446fa3a95df1e8b78f25e1babc41e46edd200821 upstream.

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@xxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 include/uapi/linux/usb/ch9.h |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/include/uapi/linux/usb/ch9.h
+++ b/include/uapi/linux/usb/ch9.h
@@ -906,6 +906,12 @@ 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