| Message ID | 20221106214804.2814-1-j@jannau.net |
|---|---|
| State | New |
| Headers | show |
| Series | [1/1] usb: dwc3: Do not get extcon device when usb-role-switch is used | expand |
Hi, On Sun, Nov 06, 2022, Janne Grunau wrote: > The change breaks device tree based platforms with PHY device and use > usb-role-switch instead of an extcon switch. extcon_find_edev_by_node() > will return EPROBE_DEFER if it can not find a device so probing without > an extcon device will be deferred indefinitely. Fix this by > explicitly checking for usb-role-switch. > At least the out-of-tree USB3 support on Apple silicon based platforms > using dwc3 with tipd USB Type-C and PD controller is affected by this > issue. > > Fixes: d182c2e1bc92 ("usb: dwc3: Don't switch OTG -> peripheral if extcon is present") > Cc: stable@kernel.org > Signed-off-by: Janne Grunau <j@jannau.net> > --- > drivers/usb/dwc3/core.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index c0e7c76dc5c8..1f348bc867c2 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -1710,6 +1710,16 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc) > if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) > return extcon_get_extcon_dev(name); > > + /* > + * Check explicitly if "usb-role-switch" is used since > + * extcon_find_edev_by_node() can not be used to check the absence of can not -> can't or cannot > + * an extcon device. In the absence of an device it will always return "a" device, > + * EPROBE_DEFER. > + */ > + if (IS_ENABLED(CONFIG_USB_ROLE_SWITCH) && > + device_property_read_bool(dev, "usb-role-switch")) > + return NULL; > + > /* > * Try to get an extcon device from the USB PHY controller's "port" > * node. Check if it has the "port" node first, to avoid printing the > -- > 2.37.3 > Looks like the "port" node check from c824c73a5e08 ("usb: dwc3: drd: Avoid error when extcon is missing") did not account for this platform setup. This looks fine to me. Should we cleanup the incomplete check and stale comment right after this too (as a separate patch)? Thanks, Thinh
On Tue, Nov 08, 2022 at 02:02:19AM +0000, Thinh Nguyen wrote: > Hi, > > On Sun, Nov 06, 2022, Janne Grunau wrote: > > The change breaks device tree based platforms with PHY device and use > > usb-role-switch instead of an extcon switch. extcon_find_edev_by_node() > > will return EPROBE_DEFER if it can not find a device so probing without > > an extcon device will be deferred indefinitely. Fix this by > > explicitly checking for usb-role-switch. > > At least the out-of-tree USB3 support on Apple silicon based platforms > > using dwc3 with tipd USB Type-C and PD controller is affected by this > > issue. > > > > Fixes: d182c2e1bc92 ("usb: dwc3: Don't switch OTG -> peripheral if extcon is present") > > Cc: stable@kernel.org > > Signed-off-by: Janne Grunau <j@jannau.net> > > --- > > drivers/usb/dwc3/core.c | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > > index c0e7c76dc5c8..1f348bc867c2 100644 > > --- a/drivers/usb/dwc3/core.c > > +++ b/drivers/usb/dwc3/core.c > > @@ -1710,6 +1710,16 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc) > > if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) > > return extcon_get_extcon_dev(name); > > > > + /* > > + * Check explicitly if "usb-role-switch" is used since > > + * extcon_find_edev_by_node() can not be used to check the absence of > > can not -> can't or cannot "can not" is fine. > > > + * an extcon device. In the absence of an device it will always return > > "a" device, Not an issue. > > + * EPROBE_DEFER. > > + */ > > + if (IS_ENABLED(CONFIG_USB_ROLE_SWITCH) && > > + device_property_read_bool(dev, "usb-role-switch")) > > + return NULL; > > + > > /* > > * Try to get an extcon device from the USB PHY controller's "port" > > * node. Check if it has the "port" node first, to avoid printing the > > -- > > 2.37.3 > > > > Looks like the "port" node check from c824c73a5e08 ("usb: dwc3: drd: > Avoid error when extcon is missing") did not account for this platform > setup. > > This looks fine to me. Should we cleanup the incomplete check and stale > comment right after this too (as a separate patch)? Is this a Reviewed-by: ? thanks, greg k-h
On Tue, Nov 08, 2022, Greg Kroah-Hartman wrote: > On Tue, Nov 08, 2022 at 02:02:19AM +0000, Thinh Nguyen wrote: > > Hi, > > > > On Sun, Nov 06, 2022, Janne Grunau wrote: > > > The change breaks device tree based platforms with PHY device and use > > > usb-role-switch instead of an extcon switch. extcon_find_edev_by_node() > > > will return EPROBE_DEFER if it can not find a device so probing without > > > an extcon device will be deferred indefinitely. Fix this by > > > explicitly checking for usb-role-switch. > > > At least the out-of-tree USB3 support on Apple silicon based platforms > > > using dwc3 with tipd USB Type-C and PD controller is affected by this > > > issue. > > > > > > Fixes: d182c2e1bc92 ("usb: dwc3: Don't switch OTG -> peripheral if extcon is present") > > > Cc: stable@kernel.org > > > Signed-off-by: Janne Grunau <j@jannau.net> > > > --- > > > drivers/usb/dwc3/core.c | 10 ++++++++++ > > > 1 file changed, 10 insertions(+) > > > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > > > index c0e7c76dc5c8..1f348bc867c2 100644 > > > --- a/drivers/usb/dwc3/core.c > > > +++ b/drivers/usb/dwc3/core.c > > > @@ -1710,6 +1710,16 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc) > > > if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) > > > return extcon_get_extcon_dev(name); > > > > > > + /* > > > + * Check explicitly if "usb-role-switch" is used since > > > + * extcon_find_edev_by_node() can not be used to check the absence of > > > > can not -> can't or cannot > > "can not" is fine. > > > > > > + * an extcon device. In the absence of an device it will always return > > > > "a" device, > > Not an issue. > > > > + * EPROBE_DEFER. > > > + */ > > > + if (IS_ENABLED(CONFIG_USB_ROLE_SWITCH) && > > > + device_property_read_bool(dev, "usb-role-switch")) > > > + return NULL; > > > + > > > /* > > > * Try to get an extcon device from the USB PHY controller's "port" > > > * node. Check if it has the "port" node first, to avoid printing the > > > -- > > > 2.37.3 > > > > > > > Looks like the "port" node check from c824c73a5e08 ("usb: dwc3: drd: > > Avoid error when extcon is missing") did not account for this platform > > setup. > > > > This looks fine to me. Should we cleanup the incomplete check and stale > > comment right after this too (as a separate patch)? > > Is this a Reviewed-by: ? > Please pick up this fix. Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com> Thanks, Thinh
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index c0e7c76dc5c8..1f348bc867c2 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -1710,6 +1710,16 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc) if (device_property_read_string(dev, "linux,extcon-name", &name) == 0) return extcon_get_extcon_dev(name); + /* + * Check explicitly if "usb-role-switch" is used since + * extcon_find_edev_by_node() can not be used to check the absence of + * an extcon device. In the absence of an device it will always return + * EPROBE_DEFER. + */ + if (IS_ENABLED(CONFIG_USB_ROLE_SWITCH) && + device_property_read_bool(dev, "usb-role-switch")) + return NULL; + /* * Try to get an extcon device from the USB PHY controller's "port" * node. Check if it has the "port" node first, to avoid printing the
The change breaks device tree based platforms with PHY device and use usb-role-switch instead of an extcon switch. extcon_find_edev_by_node() will return EPROBE_DEFER if it can not find a device so probing without an extcon device will be deferred indefinitely. Fix this by explicitly checking for usb-role-switch. At least the out-of-tree USB3 support on Apple silicon based platforms using dwc3 with tipd USB Type-C and PD controller is affected by this issue. Fixes: d182c2e1bc92 ("usb: dwc3: Don't switch OTG -> peripheral if extcon is present") Cc: stable@kernel.org Signed-off-by: Janne Grunau <j@jannau.net> --- drivers/usb/dwc3/core.c | 10 ++++++++++ 1 file changed, 10 insertions(+)