rockchip-inno-usb

rockchip-inno-usb

Downloaded from:
https://patchwork.ozlabs.org/project/uboot/patch/20210406151059.1187379-1-icenowy@aosc.io

Downloaded from:
https://patchwork.ozlabs.org/project/uboot/patch/20210406151059.1187379-1-icenowy@aosc.io

From: Icenowy Zheng <icenowy@aosc.io>
To: Simon Glass <sjg@chromium.org>, Kever Yang <kever.yang@rock-chips.com>,
 Frank Wang <frank.wang@rock-chips.com>,
 Jagan Teki <jagan@amarulasolutions.com>
Cc: u-boot@lists.denx.de,
	Icenowy Zheng <icenowy@aosc.io>
Subject: [PATCH] phy: rockchip: inno-usb2: fix hang when multiple controllers
 exit
Date: Tue,  6 Apr 2021 23:10:59 +0800
Message-Id: <20210406151059.1187379-1-icenowy@aosc.io>

The OHCI and EHCI controllers are both bound to the same PHY. They will
both do init and power_on operations when the controller is brought up
and both do power_off and exit when the controller is stopped. However,
the PHY uclass of U-Boot is not as sane as we thought -- they won't
maintain a status mark for PHYs, and thus the functions of the PHYs
could be called for multiple times. Calling init/power_on for multiple
times have no severe problems, however calling power_off/exit for
multiple times have a problem -- the first exit call will stop the PHY
clock, and power_off/exit calls after it still trying to write to PHY
registers. The write operation to PHY registers will fail because clock
is already stopped.

Adapt the count mechanism from phy-sun4i-usb to both init/exit and
power_on/power_off functions to phy-rockchip-inno-usb2 to fix this
problem. With this stopping USB controllers (manually or before booting
a kernel) will work.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Fixes: ac97a9ece14e ("phy: rockchip: Add Rockchip USB2PHY driver")
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Gbp-Pq: Topic rockchip
Gbp-Pq: Name rockchip-inno-usb.patch