usb: dwc3: Add support for device L1 exit
For the usb31 IP and from version 2.90a of the usb3 IP, the core
supports HW exit from L1 in HS. Enable it, otherwise the controller may
never exit from LPM to do a transfer.
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 3dc535a..fe1ecae 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -766,6 +766,16 @@ static int dwc3_core_init(struct dwc3 *dwc)
dwc3_writel(dwc->regs, DWC3_GUCTL2, reg);
}
+ /*
+ * Enable hardware control of sending remote wakeup in HS when
+ * the device is in the L1 state.
+ */
+ if (dwc->revision >= DWC3_REVISION_290A) {
+ reg = dwc3_readl(dwc->regs, DWC3_GUCTL1);
+ reg |= DWC3_GUCTL1_DEV_L1_EXIT_BY_HW;
+ dwc3_writel(dwc->regs, DWC3_GUCTL1, reg);
+ }
+
return 0;
err4: