Re: [PATCH v3 1/2] usb: ulpi: defer ulpi_register on ulpi_read_id timeout

On Thu, Nov 17, 2022 at 09:54:10PM +0100, Ferry Toth wrote:

Since commit 0f010171 Dual Role support on Intel Merrifield platform broke due to rearranging the call to dwc3_get_extcon().

Not sure why format is broken, you may add into your ~/.gitconfig

[core] abbrev = 12

[alias] one = show -s --pretty='format:%h ("%s")'

and run

git one 0f010171

with the result

0f0101719138 ("usb: dwc3: Don't switch OTG -> peripheral if extcon is present")

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.