Re: [PATCH v2 1/2] usb: ulpi: defer ulpi_register on ulpi_read_id timeout

From: Ferry Toth
Date: Fri Nov 11 2022 - 09:14:34 EST


+ Stephen Boyd

On 10-11-2022 22:11, Ferry Toth wrote:
Since commit 0f010171
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() on the first test write failing
with -ETIMEDOUT. Currently ulpi_read_id() expects to discover the phy via
DT when the test write fails and returns 0 in that case even if DT does not
provide the phy. As a result usb probe completes without phy.

Signed-off-by: Ferry Toth <ftoth@xxxxxxxxxxxxxx>
---
drivers/usb/common/ulpi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c
index d7c8461976ce..60e8174686a1 100644
--- a/drivers/usb/common/ulpi.c
+++ b/drivers/usb/common/ulpi.c
@@ -207,7 +207,7 @@ static int ulpi_read_id(struct ulpi *ulpi)
/* Test the interface */
ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa);
if (ret < 0)
- goto err;
+ return ret;
ret = ulpi_read(ulpi, ULPI_SCRATCH);
if (ret < 0)

Would this affect others phys (like qcom HSIC)? I'm not sure if failing the test write is a normal behavior.