DCTL.ULSTCHNGREQ is a write-only field. When doing a read-modify-write
to DCTL, the driver must make sure that there's no unintended link state
change request from whatever is read from DCTL.ULSTCHNGREQ. Set link
state change to no-action when the driver writes to DCTL.
Signed-off-by: Thinh Nguyen <thinhn@xxxxxxxxxxxx>
---
drivers/usb/dwc3/gadget.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 86dc1db788a9..24178b4b9d46 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -57,6 +57,8 @@ int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
return -EINVAL;
}
+ /* Don't send link state change request */
+ reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
return 0;
@@ -1822,6 +1824,9 @@ static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
dwc->pullups_connected = false;
}
+ /* Don't send link state change request */
+ reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
+
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
do {
@@ -2744,6 +2749,10 @@ static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
int reg;
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+
+ /* Don't send link state change request */
+ reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
+
reg &= ~DWC3_DCTL_INITU1ENA;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
@@ -2799,6 +2808,10 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
dwc3_reset_gadget(dwc);
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+
+ /* Don't send link state change request */
+ reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
+
reg &= ~DWC3_DCTL_TSTCTRL_MASK;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
dwc->test_mode = false;
@@ -2904,10 +2917,15 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
if (dwc->has_lpm_erratum && dwc->revision >= DWC3_REVISION_240A)
reg |= DWC3_DCTL_NYET_THRES(dwc->lpm_nyet_threshold);
+ /* Don't send link state change request */
+ reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
} else {
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
+
+ /* Don't send link state change request */
+ reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
}
@@ -3017,6 +3035,9 @@ static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
reg &= ~u1u2;
+ /* Don't send link state change request */
+ reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
+
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
break;
default:
--
2.11.0
