usb: dwc3: Enable usb2 LPM only when connected as usb2.0
Synopsys says:
The HIRD Threshold field must be set to ‘0’ when the device core is
operating in super speed mode.
This patch implements above statement.
Cc: <stable@vger.kernel.org> # v3.6 v3.7 v3.8
Acked-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 0b92e98..113ec80 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2154,6 +2154,23 @@
break;
}
+ /* Enable USB2 LPM Capability */
+
+ if ((dwc->revision > DWC3_REVISION_194A)
+ && (speed != DWC3_DCFG_SUPERSPEED)) {
+ reg = dwc3_readl(dwc->regs, DWC3_DCFG);
+ reg |= DWC3_DCFG_LPM_CAP;
+ dwc3_writel(dwc->regs, DWC3_DCFG, reg);
+
+ reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+ reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
+
+ /* TODO: This should be configurable */
+ reg |= DWC3_DCTL_HIRD_THRES(28);
+
+ dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ }
+
/* Recent versions support automatic phy suspend and don't need this */
if (dwc->revision < DWC3_REVISION_194A) {
/* Suspend unneeded PHY */
@@ -2460,20 +2477,8 @@
DWC3_DEVTEN_DISCONNEVTEN);
dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
- /* Enable USB2 LPM and automatic phy suspend only on recent versions */
+ /* automatic phy suspend only on recent versions */
if (dwc->revision >= DWC3_REVISION_194A) {
- reg = dwc3_readl(dwc->regs, DWC3_DCFG);
- reg |= DWC3_DCFG_LPM_CAP;
- dwc3_writel(dwc->regs, DWC3_DCFG, reg);
-
- reg = dwc3_readl(dwc->regs, DWC3_DCTL);
- reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
-
- /* TODO: This should be configurable */
- reg |= DWC3_DCTL_HIRD_THRES(28);
-
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
-
dwc3_gadget_usb2_phy_suspend(dwc, false);
dwc3_gadget_usb3_phy_suspend(dwc, false);
}