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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>
Wed, 7 Sep 2016 06:32:38 +0000 (08:32 +0200)
commitcb68ec1ce547aef16a9f257ce025b2489c59f227
tree14fdce72a349adba05c65c9b6817ab7816919fed
parent161427073a79db33d6a99223ce50a25386e27c21
usb: ehci: change order of register cleanup during shutdown

commit bc337b51508beb2d039aff5074a76cfe1c212030 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/ehci-hcd.c