diff options
| author | Ingo Molnar <mingo@kernel.org> | 2013-08-15 10:00:09 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2013-08-15 10:00:09 +0200 |
| commit | c9572f010d369d9905309f63e31180f291b66a8a (patch) | |
| tree | fbca2a0576c4223790e23a3c1d5f50e2bdf64e10 /include/uapi/linux/usb | |
| parent | 58cea307432e3376293e6b2be88d1f6e6e99274a (diff) | |
| parent | d4e4ab86bcba5a72779c43dc1459f71fea3d89c8 (diff) | |
Merge tag 'v3.11-rc5' into perf/core
Merge Linux 3.11-rc5, to sync up with the latest upstream fixes since -rc1.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/uapi/linux/usb')
| -rw-r--r-- | include/uapi/linux/usb/ch11.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/include/uapi/linux/usb/ch11.h b/include/uapi/linux/usb/ch11.h index 7692dc69ccf7..331499d597fa 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 */ |