| Message ID | 20220425121340.1362-2-heikki.krogerus@linux.intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | usb: core: acpi: Rely on the sysdev pointer | expand |
On Mon, Apr 25, 2022 at 3:41 PM Heikki Krogerus <heikki.krogerus@linux.intel.com> wrote: > > The controller device (hcd) does not always have the ACPI > companion assigned to it at all. We can not rely on it when > finding the ACPI companion for the root hub. Instead we need > to use the sysdev pointer here. ... > if (!udev->parent) { > /* root hub is only child (_ADR=0) under its parent, the HC */ I believe the comment can be amended now to point out that we use the physical device representing the parent of this child, and not (always) a direct parent of the device in terms of Linux device model. > - adev = ACPI_COMPANION(udev->dev.parent); > + adev = ACPI_COMPANION(udev->bus->sysdev); > return acpi_find_child_device(adev, 0, false); > }
On Tue, Apr 26, 2022 at 12:18:24PM +0200, Andy Shevchenko wrote: > On Mon, Apr 25, 2022 at 3:41 PM Heikki Krogerus > <heikki.krogerus@linux.intel.com> wrote: > > > > The controller device (hcd) does not always have the ACPI > > companion assigned to it at all. We can not rely on it when > > finding the ACPI companion for the root hub. Instead we need > > to use the sysdev pointer here. > > ... > > > if (!udev->parent) { > > /* root hub is only child (_ADR=0) under its parent, the HC */ > > I believe the comment can be amended now to point out that we use the > physical device representing the parent of this child, and not > (always) a direct parent of the device in terms of Linux device model. Okay, I'll try to improve the comment. > > - adev = ACPI_COMPANION(udev->dev.parent); > > + adev = ACPI_COMPANION(udev->bus->sysdev); > > return acpi_find_child_device(adev, 0, false); > > } thanks,
diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi.c index bb1da35eb891e..fbaf5045507bb 100644 --- a/drivers/usb/core/usb-acpi.c +++ b/drivers/usb/core/usb-acpi.c @@ -206,7 +206,7 @@ usb_acpi_find_companion_for_device(struct usb_device *udev) if (!udev->parent) { /* root hub is only child (_ADR=0) under its parent, the HC */ - adev = ACPI_COMPANION(udev->dev.parent); + adev = ACPI_COMPANION(udev->bus->sysdev); return acpi_find_child_device(adev, 0, false); }
The controller device (hcd) does not always have the ACPI companion assigned to it at all. We can not rely on it when finding the ACPI companion for the root hub. Instead we need to use the sysdev pointer here. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> --- drivers/usb/core/usb-acpi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)