Am 12.01.2018 um 00:32 schrieb Arnd Bergmann:
On Wed, Jan 10, 2018 at 1:15 PM, Stefan Wahren <stefan.wahren@xxxxxxxx> wrote:
Hi Arnd,
Am 09.01.2018 um 22:33 schrieb Arnd Bergmann:
On Tue, Jan 9, 2018 at 8:28 PM, Stefan Wahren <stefan.wahren@xxxxxxxx>
wrote:
The dwc2 USB driver tries to find a generic PHY first and then look
for an old style USB PHY. In case of a valid generic PHY node without
a PHY driver, the PHY layer will return -EPROBE_DEFER forever. So dwc2
will never tries for an USB PHY.
Fix this issue by finding a generic PHY and an old style USB PHY
at once.
This would fix only one of the USB controllers (dwc2), but not the others
that are affected. As I wrote in my suggested patch, dwc3 appears to be
affected the same way, and all other host drivers that call usb_add_hcd()
without first setting hcd->phy would suffer from this as well.
If we go down the route of addressing it here in the hcd drivers, we
should
at least change all three of those, and hope this doesn't regress in
another way.
Arnd
i fully unterstand. But we leaving the path of "fixing a critical issue on
BCM2835" and go to "fixing multiple USB host controller". I do this all in
my spare time and don't have any of the other USB controller available. So
before i proceed with any other patch i like so see some feedback from John,
Greg or Felipe.
After finalizing this patch i think the chance is little that this would be
applied to 4.15. So i seems to me that we still revert my DT clean up patch.
Could you confirm that this simpler patch fixes the problem for you?
My feeling right now is that this would be the least invasive variant.
This is obviously a critical regression for BCM2835, but I'm fairly sure
it's just as critical for a lot of other SoCs that haven't done as much
testing on linux-next.
Even worse arm64 and mips could be affected, too.
Hans has already verified the earlier (more complex) version, but my
analysis today has made it very likely that this one is fully sufficient
to fix all affected platforms.
Reverting all nine patches that add #phy-cells would still be an option,
but seems way more invasive at this point.
Arnd
diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index b4964b067aec..93b55fb71d54 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -410,6 +410,10 @@ static struct phy *_of_phy_get(struct device_node
*np, int index)
if (ret)
return ERR_PTR(-ENODEV);
+ /* This phy type handled by the usb-phy subsystem for now */
+ if (of_device_is_compatible(np, "usb-nop-xceiv"))
+ return ERR_PTR(-ENODEV);
+
mutex_lock(&phy_provider_mutex);
phy_provider = of_phy_provider_lookup(args.np);
if (IS_ERR(phy_provider) || !try_module_get(phy_provider->owner)) {
I tried this, but it doesn't work. "np" is the node of the USB
controller, not of the phy?
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
