usb: gadget: dummy: fix nonsensical comparisons
authorArnd Bergmann <arnd@arndb.de>
Thu, 7 Sep 2017 14:14:31 +0000 (16:14 +0200)
committerFelipe Balbi <felipe.balbi@linux.intel.com>
Wed, 20 Sep 2017 11:57:28 +0000 (14:57 +0300)
commit7661ca09b2ff98f48693f431bb01fed62830e433
treee6df4d7d67bafd490df9a7233c73d750ed13f50c
parent641663a19f6002ecc5c5af517a5184d4164cc749
usb: gadget: dummy: fix nonsensical comparisons

gcc-8 points out two comparisons that are clearly bogus
and almost certainly not what the author intended to write:

drivers/usb/gadget/udc/dummy_hcd.c: In function 'set_link_state_by_speed':
drivers/usb/gadget/udc/dummy_hcd.c:379:31: error: bitwise comparison always evaluates to false [-Werror=tautological-compare]
         USB_PORT_STAT_ENABLE) == 1 &&
                               ^~
drivers/usb/gadget/udc/dummy_hcd.c:381:25: error: bitwise comparison always evaluates to false [-Werror=tautological-compare]
      USB_SS_PORT_LS_U0) == 1 &&
                         ^~

I looked at the code for a bit and came up with a change that makes
it look like what the author probably meant here. This makes it
look reasonable to me and to gcc, shutting up the warning.

It does of course change behavior as the two conditions are actually
evaluated rather than being hardcoded to false, and I have made no
attempt at verifying that the changed logic makes sense in the context
of a USB HCD, so that part needs to be reviewed carefully.

Fixes: 1cd8fd2887e1 ("usb: gadget: dummy_hcd: add SuperSpeed support")
Cc: Tatyana Brokhman <tlinder@codeaurora.org>
Cc: Felipe Balbi <balbi@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
drivers/usb/gadget/udc/dummy_hcd.c