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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-07-29 11:50:17 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-07-29 11:50:17 -0700
commit9c5891bd4342349a200676d33f742dd1b864822c (patch)
treeb14c1698f2d8ce5276e1befd562f6398a46b48b9 /include/uapi/linux/usb/ch11.h
parentecda040ff3724f021a96491ecee88d48e968c153 (diff)
parent5ae90d8e467e625e447000cb4335c4db973b1095 (diff)
Merge 3.11-rc3 into char-misc-next.
This resolves a merge issue with: drivers/misc/mei/init.c Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/uapi/linux/usb/ch11.h')
-rw-r--r--include/uapi/linux/usb/ch11.h11
1 files changed, 11 insertions, 0 deletions
diff --git a/include/uapi/linux/usb/ch11.h b/include/uapi/linux/usb/ch11.h
index 7692dc69ccf..331499d597f 100644
--- a/include/uapi/linux/usb/ch11.h
+++ b/include/uapi/linux/usb/ch11.h
@@ -11,6 +11,17 @@
#include <linux/types.h> /* __u8 etc */
+/* This is arbitrary.
+ * From USB 2.0 spec Table 11-13, offset 7, a hub can
+ * have up to 255 ports. The most yet reported is 10.
+ *
+ * Current Wireless USB host hardware (Intel i1480 for example) allows
+ * up to 22 devices to connect. Upcoming hardware might raise that
+ * limit. Because the arrays need to add a bit for hub status data, we
+ * use 31, so plus one evens out to four bytes.
+ */
+#define USB_MAXCHILDREN 31
+
/*
* Hub request types
*/