usb: host: xhci: mvebu: make USB 3.0 PHY optional for Armada 3720

usb: host: xhci: mvebu: make USB 3.0 PHY optional for Armada 3720

Older ATF does not provide SMC call for USB 3.0 phy power on functionality
and therefore initialization of xhci-hcd is failing when older version of
ATF is used. In this case phy_power_on() function returns -EOPNOTSUPP.

[    3.108467] mvebu-a3700-comphy d0018300.phy: unsupported SMC call, try updating your firmware
[    3.117250] phy phy-d0018300.phy.0: phy poweron failed --> -95
[    3.123465] xhci-hcd: probe of d0058000.usb failed with error -95

This patch introduces a new plat_setup callback for xhci platform drivers
which is called prior calling usb_add_hcd() function. This function at its
beginning skips PHY init if hcd->skip_phy_initialization is set.

Current init_quirk callback for xhci platform drivers is called from
xhci_plat_setup() function which is called after chip reset completes.
It happens in the middle of the usb_add_hcd() function and therefore this
callback cannot be used for setting if PHY init should be skipped or not.

For Armada 3720 this patch introduce a new xhci_mvebu_a3700_plat_setup()
function configured as a xhci platform plat_setup callback. This new
function calls phy_power_on() and in case it returns -EOPNOTSUPP then
XHCI_SKIP_PHY_INIT quirk is set to instruct xhci-plat to skip PHY
initialization.

This patch fixes above failure by ignoring 'not supported' error in
xhci-hcd driver. In this case it is expected that phy is already power on.

It fixes initialization of xhci-hcd on Espressobin boards where is older
Marvell's Arm Trusted Firmware without SMC call for USB 3.0 phy power.

This is regression introduced in commit bd3d25b07342 ("arm64: dts: marvell:
armada-37xx: link USB hosts with their PHYs") where USB 3.0 phy was defined
and therefore xhci-hcd on Espressobin with older ATF started failing.

Fixes: bd3d25b07342 ("arm64: dts: marvell: armada-37xx: link USB hosts with their PHYs")
Cc: <stable@vger.kernel.org> # 5.1+: ea17a0f153af: phy: marvell: comphy: Convert internal SMCC firmware return codes to errno
Cc: <stable@vger.kernel.org> # 5.1+: f768e718911e: usb: host: xhci-plat: add priv quirk for skip PHY initialization
Tested-by: Tomasz Maciej Nowak <tmn505@gmail.com>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> # On R-Car
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> # xhci-plat
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20210201150803.7305-1-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>