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usb: ehci: change order of register cleanup during shutdown
authorMarc Ohlf <ohlf@mkt-sys.de>
Wed, 3 Aug 2016 09:51:54 +0000 (11:51 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 9 Aug 2016 14:14:18 +0000 (16:14 +0200)
commitbc337b51508beb2d039aff5074a76cfe1c212030
treee3cb2492951b8cccd32f1872617a30cbf6a4b51c
parentaed9d65ac3278d4febd8665bd7db59ef53e825fe
usb: ehci: change order of register cleanup during shutdown

In ehci_turn_off_all_ports() all EHCI port registers are cleared to zero.
On some hardware, this can lead to an system hang,
when ehci_port_power() accesses the already cleared registers.

This patch changes the order of cleanup.
First call ehci_port_power() which respects the current bits in
port status registers
and afterwards cleanup the hard way by setting everything to zero.

Signed-off-by: Marc Ohlf <ohlf@mkt-sys.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/ehci-hcd.c