[PATCH 4.9 124/172] usb: dwc2: gadget: Fix GUSBCFG.USBTRDTIM value

[Greg Kroah-Hartman]

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

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

From: Amelie Delaunay <amelie.delaunay@xxxxxx>


[ Upstream commit ca02954ada711b08e5b0d84590a631fd63ed39f9 ]

USBTrdTim must be programmed to 0x5 when phy has a UTMI+ 16-bit wide
interface or 0x9 when it has a 8-bit wide interface.
GUSBCFG reset value (Value After Reset: 0x1400) sets USBTrdTim to 0x5.
In case of 8-bit UTMI+, without clearing GUSBCFG.USBTRDTIM mask, USBTrdTim
results in 0xD (0x5 | 0x9).
That's why we need to clear GUSBCFG.USBTRDTIM mask before setting USBTrdTim
value, to ensure USBTrdTim is correctly set in case of 8-bit UTMI+.

Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx>
Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/dwc2/gadget.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/usb/dwc2/gadget.c
+++ b/drivers/usb/dwc2/gadget.c
@@ -2532,7 +2532,7 @@ void dwc2_hsotg_core_init_disconnected(s
 	/* keep other bits untouched (so e.g. forced modes are not lost) */
 	usbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
 	usbcfg &= ~(GUSBCFG_TOUTCAL_MASK | GUSBCFG_PHYIF16 | GUSBCFG_SRPCAP |
-		GUSBCFG_HNPCAP);
+		GUSBCFG_HNPCAP | GUSBCFG_USBTRDTIM_MASK);
 
 	/* set the PLL on, remove the HNP/SRP and set the PHY */
 	val = (hsotg->phyif == GUSBCFG_PHYIF8) ? 9 : 5;
@@ -3403,7 +3403,7 @@ static void dwc2_hsotg_init(struct dwc2_
 	/* keep other bits untouched (so e.g. forced modes are not lost) */
 	usbcfg = dwc2_readl(hsotg->regs + GUSBCFG);
 	usbcfg &= ~(GUSBCFG_TOUTCAL_MASK | GUSBCFG_PHYIF16 | GUSBCFG_SRPCAP |
-		GUSBCFG_HNPCAP);
+		GUSBCFG_HNPCAP | GUSBCFG_USBTRDTIM_MASK);
 
 	/* set the PLL on, remove the HNP/SRP and set the PHY */
 	trdtim = (hsotg->phyif == GUSBCFG_PHYIF8) ? 9 : 5;