[PATCH 4.19 080/170] usb: dwc2: disable power_down on Amlogic devices

[Greg Kroah-Hartman]

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>

commit cc10ce0c51b13d1566d0ec1dcb472fb86330b391 upstream.

Disable power_down by setting the parameter to
DWC2_POWER_DOWN_PARAM_NONE. This fixes a problem on various Amlogic
Meson SoCs where USB devices are only recognized when plugged in before
booting Linux. A hot-plugged USB device was not detected even though the
device got power (my USB thumb drive for example has an LED which lit
up).

A similar fix was implemented for Rockchip SoCs in commit c216765d3a1def
("usb: dwc2: disable power_down on rockchip devices"). That commit
suggests that a change in the dwc2 driver is the cause because the
default value for the "hibernate" parameter (which then got renamed to
"power_down" to support other modes) was changed in the v4.17 merge
window with:
commit 6d23ee9caa6790 ("Merge tag 'usb-for-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing").

Cc: <stable@xxxxxxxxxxxxxxx> # 4.19
Acked-by: Minas Harutyunyan <hminas@xxxxxxxxxxxx>
Suggested-by: Christian Hewitt <christianshewitt@xxxxxxxxx>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/dwc2/params.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/usb/dwc2/params.c
+++ b/drivers/usb/dwc2/params.c
@@ -110,6 +110,7 @@ static void dwc2_set_amlogic_params(stru
 	p->phy_type = DWC2_PHY_TYPE_PARAM_UTMI;
 	p->ahbcfg = GAHBCFG_HBSTLEN_INCR8 <<
 		GAHBCFG_HBSTLEN_SHIFT;
+	p->power_down = DWC2_POWER_DOWN_PARAM_NONE;
 }
 
 static void dwc2_set_amcc_params(struct dwc2_hsotg *hsotg)