* [PATCH v2 1/4] usb: dwc3: gadget: Don't send unintended link state change
2019-10-24 2:15 [PATCH v2 0/4] usb: gadget: Link state changes Thinh Nguyen
@ 2019-10-24 2:15 ` Thinh Nguyen
2019-10-24 2:15 ` [PATCH v2 2/4] usb: dwc3: gadget: Set link state to RX_Detect on disconnect Thinh Nguyen
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Thinh Nguyen @ 2019-10-24 2:15 UTC (permalink / raw)
To: Felipe Balbi, Thinh Nguyen, linux-usb; +Cc: John Youn
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@synopsys.com>
---
Changes in v2:
- Create inline function to do safe write to DCTL
drivers/usb/dwc3/gadget.c | 16 +++++++---------
drivers/usb/dwc3/gadget.h | 14 ++++++++++++++
2 files changed, 21 insertions(+), 9 deletions(-)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 86dc1db788a9..85adc718808a 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -57,7 +57,7 @@ int dwc3_gadget_set_test_mode(struct dwc3 *dwc, int mode)
return -EINVAL;
}
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ dwc3_gadget_dctl_write_safe(dwc, reg);
return 0;
}
@@ -1822,7 +1822,7 @@ static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)
dwc->pullups_connected = false;
}
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ dwc3_gadget_dctl_write_safe(dwc, reg);
do {
reg = dwc3_readl(dwc->regs, DWC3_DSTS);
@@ -2745,10 +2745,8 @@ static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_INITU1ENA;
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
-
reg &= ~DWC3_DCTL_INITU2ENA;
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ dwc3_gadget_dctl_write_safe(dwc, reg);
dwc3_disconnect_gadget(dwc);
@@ -2800,7 +2798,7 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_TSTCTRL_MASK;
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ dwc3_gadget_dctl_write_safe(dwc, reg);
dwc->test_mode = false;
dwc3_clear_stall_all_ep(dwc);
@@ -2904,11 +2902,11 @@ 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);
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ dwc3_gadget_dctl_write_safe(dwc, reg);
} else {
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_HIRD_THRES_MASK;
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ dwc3_gadget_dctl_write_safe(dwc, reg);
}
dep = dwc->eps[0];
@@ -3017,7 +3015,7 @@ static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
reg &= ~u1u2;
- dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+ dwc3_gadget_dctl_write_safe(dwc, reg);
break;
default:
/* do nothing */
diff --git a/drivers/usb/dwc3/gadget.h b/drivers/usb/dwc3/gadget.h
index 5faf4d1249e0..fbc7d8013f0b 100644
--- a/drivers/usb/dwc3/gadget.h
+++ b/drivers/usb/dwc3/gadget.h
@@ -127,4 +127,18 @@ static inline void dwc3_gadget_ep_get_transfer_index(struct dwc3_ep *dep)
dep->resource_index = DWC3_DEPCMD_GET_RSC_IDX(res_id);
}
+/**
+ * dwc3_gadget_dctl_write_safe - write to DCTL safe from link state change
+ * @dwc: pointer to our context structure
+ * @value: value to write to DCTL
+ *
+ * Use this function when doing read-modify-write to DCTL. It will not
+ * send link state change request.
+ */
+static inline void dwc3_gadget_dctl_write_safe(struct dwc3 *dwc, u32 value)
+{
+ value &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
+ dwc3_writel(dwc->regs, DWC3_DCTL, value);
+}
+
#endif /* __DRIVERS_USB_DWC3_GADGET_H */
--
2.11.0
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v2 3/4] usb: dwc3: gadget: Clear DCTL.ULSTCHNGREQ before set
2019-10-24 2:15 [PATCH v2 0/4] usb: gadget: Link state changes Thinh Nguyen
2019-10-24 2:15 ` [PATCH v2 1/4] usb: dwc3: gadget: Don't send unintended link state change Thinh Nguyen
2019-10-24 2:15 ` [PATCH v2 2/4] usb: dwc3: gadget: Set link state to RX_Detect on disconnect Thinh Nguyen
@ 2019-10-24 2:15 ` Thinh Nguyen
2019-10-24 2:16 ` [PATCH v2 4/4] usb: dwc3: debug: Remove newline printout Thinh Nguyen
3 siblings, 0 replies; 5+ messages in thread
From: Thinh Nguyen @ 2019-10-24 2:15 UTC (permalink / raw)
To: Felipe Balbi, Thinh Nguyen, linux-usb; +Cc: John Youn
Send a no-action link state change request before the actual request
so DWC3 can send the same request whenever we call
dwc3_gadget_set_link_state().
Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
drivers/usb/dwc3/gadget.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 5856c8c96418..7f97856e6b20 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -111,6 +111,9 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
reg = dwc3_readl(dwc->regs, DWC3_DCTL);
reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
+ /* set no action before sending new link state change */
+ dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+
/* set requested state */
reg |= DWC3_DCTL_ULSTCHNGREQ(state);
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
--
2.11.0
^ permalink raw reply related [flat|nested] 5+ messages in thread