Since commit 0f0101719138 ("usb: dwc3: Don't switch OTG -> peripheral if extcon is present"),
Dual Role support on Intel Merrifield platform broke due to rearranging
the call to dwc3_get_extcon().
It appears to be caused by ulpi_read_id() masking the timeout on the first
test write. In the past dwc3 probe continued by calling dwc3_core_soft_reset()
followed by dwc3_get_extcon() which happend to return -EPROBE_DEFER.
On deferred probe ulpi_read_id() finally succeeded. Due to above mentioned
rearranging -EPROBE_DEFER is not returned and probe completes without phy.
As we now changed ulpi_read_id() to return -ETIMEDOUT in this case, we
need to handle the error by calling dwc3_core_soft_reset() and request
-EPROBE_DEFER. On deferred probe ulpi_read_id() is retried and succeeds.
Fixes: ef6a7bcfb01c ("usb: ulpi: Support device discovery via DT")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ferry Toth <ftoth@xxxxxxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 648f1c570021..2779f17bffaf 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1106,8 +1106,13 @@ static int dwc3_core_init(struct dwc3 *dwc)
if (!dwc->ulpi_ready) {
ret = dwc3_core_ulpi_init(dwc);
- if (ret)
+ if (ret) {
+ if (ret == -ETIMEDOUT) {
+ dwc3_core_soft_reset(dwc);
+ ret = -EPROBE_DEFER;
+ }
goto err0;
+ }
dwc->ulpi_ready = true;
}
--
2.37.2
