[PATCH 3/6] usb: dwc3: gadget: only resume USB2 PHY in <=HIGHSPEED

[A. Sverdlin]

From: Felipe Balbi <felipe.balbi at linux.intel.com>

Upstream Linux commit ab2a92e7a608.

As a micro-power optimization, let's only resume the
USB2 PHY if we're working on <=HIGHSPEED. If we're
gonna work on SUPERSPEED or SUPERSPEED+, there's no
point in resuming the USB2 PHY.

Fixes: 2b0f11df84bb ("usb: dwc3: gadget: clear SUSPHY bit before ep cmds")
Signed-off-by: Felipe Balbi <felipe.balbi at linux.intel.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin at siemens.com>
---
 drivers/usb/dwc3/gadget.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 8f6513752f085..00845dbadd27a 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -314,11 +314,13 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
 	 * We will also set SUSPHY bit to what it was before returning as stated
 	 * by the same section on Synopsys databook.
 	 */
-	reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
-	if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
-		susphy = true;
-		reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
-		dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+	if (dwc->gadget.speed <= USB_SPEED_HIGH) {
+		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+		if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
+			susphy = true;
+			reg &= ~DWC3_GUSB2PHYCFG_SUSPHY;
+			dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
+		}
 	}
 
 	dwc3_writel(dwc->regs, DWC3_DEPCMDPAR0(ep), params->param0);
-- 
2.44.0