| Message ID | 20210309134818.63118-2-mika.westerberg@linux.intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | thunderbolt: Expose details about tunneling | expand |
On Tue, Mar 09, 2021 at 04:48:16PM +0300, Mika Westerberg wrote: > Expose two environment variables for routers as part of the initial > uevent: > > USB4_VERSION=1.0 > USB4_TYPE=host|device|hub > > Userspace can use this information to expose more details about each > connected device. Only USB4 devices have USB4_VERSION but all devices > have USB4_TYPE. > > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> -----Original Message----- > From: Mika Westerberg <mika.westerberg@linux.intel.com> > Sent: Tuesday, March 9, 2021 7:48 > To: linux-usb@vger.kernel.org > Cc: Michael Jamet; Yehezkel Bernat; Andreas Noever; Lukas Wunner; Limonciello, > Mario; Christian Kellner; Benson Leung; Prashant Malani; Diego Rivas; Greg > Kroah-Hartman; Mika Westerberg > Subject: [PATCH 1/3] thunderbolt: Add details to router uevent > > > [EXTERNAL EMAIL] > > Expose two environment variables for routers as part of the initial > uevent: > > USB4_VERSION=1.0 > USB4_TYPE=host|device|hub Presumably this will then show up in the uevent like this for a host controller: DEVTYPE=thunderbolt_device USB4_VERSION=1.0 USB4_TYPE=host Since it's specifically for USB4, how about if you instead have new devtypes? TBT3: DEVTYPE=thunderbolt_device USB4: DEVTYPE=usb4_host|usb4_device|usb4_hub That would at least make it clearer to userspace to make a delineation if it's legacy device or not. I don't know if that's actually valuable information however. > > Userspace can use this information to expose more details about each > connected device. Only USB4 devices have USB4_VERSION but all devices > have USB4_TYPE. > > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> > --- > drivers/thunderbolt/switch.c | 34 ++++++++++++++++++++++++++++++++++ > 1 file changed, 34 insertions(+) > > diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c > index 72b43c7c0651..a82032c081e8 100644 > --- a/drivers/thunderbolt/switch.c > +++ b/drivers/thunderbolt/switch.c > @@ -1827,6 +1827,39 @@ static void tb_switch_release(struct device *dev) > kfree(sw); > } > > +static int tb_switch_uevent(struct device *dev, struct kobj_uevent_env *env) > +{ > + struct tb_switch *sw = tb_to_switch(dev); > + const char *type; > + > + if (sw->config.thunderbolt_version == USB4_VERSION_1_0) { > + if (add_uevent_var(env, "USB4_VERSION=1.0")) > + return -ENOMEM; > + } > + > + if (!tb_route(sw)) { > + type = "host"; > + } else { > + const struct tb_port *port; > + bool hub = false; > + > + /* Device is hub if it has any downstream ports */ > + tb_switch_for_each_port(sw, port) { > + if (!port->disabled && !tb_is_upstream_port(port) && > + tb_port_is_null(port)) { > + hub = true; > + break; > + } > + } > + > + type = hub ? "hub" : "device"; > + } > + > + if (add_uevent_var(env, "USB4_TYPE=%s", type)) > + return -ENOMEM; > + return 0; > +} > + > /* > * Currently only need to provide the callbacks. Everything else is handled > * in the connection manager. > @@ -1860,6 +1893,7 @@ static const struct dev_pm_ops tb_switch_pm_ops = { > struct device_type tb_switch_type = { > .name = "thunderbolt_device", > .release = tb_switch_release, > + .uevent = tb_switch_uevent, > .pm = &tb_switch_pm_ops, > }; > > -- > 2.30.1
Hi Mario, On Wed, Mar 10, 2021 at 05:28:19PM +0000, Limonciello, Mario wrote: > > > > -----Original Message----- > > From: Mika Westerberg <mika.westerberg@linux.intel.com> > > Sent: Tuesday, March 9, 2021 7:48 > > To: linux-usb@vger.kernel.org > > Cc: Michael Jamet; Yehezkel Bernat; Andreas Noever; Lukas Wunner; Limonciello, > > Mario; Christian Kellner; Benson Leung; Prashant Malani; Diego Rivas; Greg > > Kroah-Hartman; Mika Westerberg > > Subject: [PATCH 1/3] thunderbolt: Add details to router uevent > > > > > > [EXTERNAL EMAIL] > > > > Expose two environment variables for routers as part of the initial > > uevent: > > > > USB4_VERSION=1.0 > > USB4_TYPE=host|device|hub > > Presumably this will then show up in the uevent like this for a host controller: > DEVTYPE=thunderbolt_device > USB4_VERSION=1.0 > USB4_TYPE=host > > Since it's specifically for USB4, how about if you instead have new devtypes? > TBT3: > DEVTYPE=thunderbolt_device > > USB4: > DEVTYPE=usb4_host|usb4_device|usb4_hub > > That would at least make it clearer to userspace to make a delineation if it's > legacy device or not. I don't know if that's actually valuable information however. Unfortunately we can't do that. DEVTYPE is generated by the driver core based on the struct device_type we register for routers (switches). Also bolt, and I think fwupd too, already use DEVTYPE to distinguish routers from other devices (like XDomains etc).
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 72b43c7c0651..a82032c081e8 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -1827,6 +1827,39 @@ static void tb_switch_release(struct device *dev) kfree(sw); } +static int tb_switch_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct tb_switch *sw = tb_to_switch(dev); + const char *type; + + if (sw->config.thunderbolt_version == USB4_VERSION_1_0) { + if (add_uevent_var(env, "USB4_VERSION=1.0")) + return -ENOMEM; + } + + if (!tb_route(sw)) { + type = "host"; + } else { + const struct tb_port *port; + bool hub = false; + + /* Device is hub if it has any downstream ports */ + tb_switch_for_each_port(sw, port) { + if (!port->disabled && !tb_is_upstream_port(port) && + tb_port_is_null(port)) { + hub = true; + break; + } + } + + type = hub ? "hub" : "device"; + } + + if (add_uevent_var(env, "USB4_TYPE=%s", type)) + return -ENOMEM; + return 0; +} + /* * Currently only need to provide the callbacks. Everything else is handled * in the connection manager. @@ -1860,6 +1893,7 @@ static const struct dev_pm_ops tb_switch_pm_ops = { struct device_type tb_switch_type = { .name = "thunderbolt_device", .release = tb_switch_release, + .uevent = tb_switch_uevent, .pm = &tb_switch_pm_ops, };
Expose two environment variables for routers as part of the initial uevent: USB4_VERSION=1.0 USB4_TYPE=host|device|hub Userspace can use this information to expose more details about each connected device. Only USB4 devices have USB4_VERSION but all devices have USB4_TYPE. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> --- drivers/thunderbolt/switch.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+)