This is a note to let you know that I've just added the patch titled
usb: ulpi: defer ulpi_register on ulpi_read_id timeout
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-ulpi-defer-ulpi_register-on-ulpi_read_id-timeout.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 8a7b31d545d3a15f0e6f5984ae16f0ca4fd76aac Mon Sep 17 00:00:00 2001
From: Ferry Toth <ftoth@xxxxxxxxxxxxxx>
Date: Mon, 5 Dec 2022 21:15:26 +0100
Subject: usb: ulpi: defer ulpi_register on ulpi_read_id timeout
From: Ferry Toth <ftoth@xxxxxxxxxxxxxx>
commit 8a7b31d545d3a15f0e6f5984ae16f0ca4fd76aac upstream.
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() 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.
Make ulpi_read_id() return -ETIMEDOUT to its user if the first test write
fails. The user should then handle it appropriately. A follow up patch
will make dwc3_core_init() set -EPROBE_DEFER in this case and bail out.
Fixes: ef6a7bcfb01c ("usb: ulpi: Support device discovery via DT")
Cc: stable@xxxxxxxxxxxxxxx
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Ferry Toth <ftoth@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20221205201527.13525-2-ftoth@xxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/common/ulpi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/usb/common/ulpi.c
+++ b/drivers/usb/common/ulpi.c
@@ -210,7 +210,7 @@ static int ulpi_read_id(struct ulpi *ulp
/* 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)
Patches currently in stable-queue which might be from ftoth@xxxxxxxxxxxxxx are
queue-4.14/usb-ulpi-defer-ulpi_register-on-ulpi_read_id-timeout.patch
