On Tue, 24 Jun 2025, Mario Limonciello wrote: > On 6/24/25 5:24 AM, Rafael J. Wysocki wrote: > > On Tue, Jun 24, 2025 at 9:22 AM Lukas Wunner <lukas@xxxxxxxxx> wrote: > > > > > > [cc += Rafael, Mika] > > > > > > On Mon, Jun 23, 2025 at 02:13:34PM -0500, Mario Limonciello wrote: > > > > From: Mario Limonciello <mario.limonciello@xxxxxxx> > > > > > > > > When a USB4 dock is unplugged the PCIe bridge it's connected to will > > > > issue a "Link Down" and "Card not detected event". The PCI core will > > > > treat this as a surprise hotplug event and unconfigure all downstream > > > > devices. This involves setting the device error state to > > > > `pci_channel_io_perm_failure` which pci_dev_is_disconnected() will > > > > check. > > > > > > > > It doesn't make sense to runtime resume disconnected devices to D0 and > > > > report the (expected) error, so bail early. > > > > > > > > Suggested-by: Lukas Wunner <lukas@xxxxxxxxx> > > > > Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> > > > > > > Reviewed-by: Lukas Wunner <lukas@xxxxxxxxx> > > > > > > > --- > > > > v4: > > > > * no info message > > > > v3: > > > > * Adjust text and subject > > > > * Add an info message instead > > > > v2: > > > > * Use pci_dev_is_disconnected() > > > > v1: > > > > https://lore.kernel.org/linux-usb/20250609020223.269407-1-superm1@xxxxxxxxxx/T/#mf95c947990d016fbfccfd11afe60b8ae08aafa0b > > > > --- > > > > drivers/pci/pci.c | 5 +++++ > > > > 1 file changed, 5 insertions(+) > > > > > > > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > > > > index 9e42090fb1089..160a9a482c732 100644 > > > > --- a/drivers/pci/pci.c > > > > +++ b/drivers/pci/pci.c > > > > @@ -1374,6 +1374,11 @@ int pci_power_up(struct pci_dev *dev) > > > > return -EIO; > > > > } > > > > > > > > + if (pci_dev_is_disconnected(dev)) { > > > > + dev->current_state = PCI_D3cold; > > > > Why not PCI_UNKNOWN? > > It was following what other situations of failure did: > * existing error in pci_power_up() > * error in pci_update_current_state() > * error in pci_set_low_power_state() > > I view all of these cases as unrecoverable failures. > > So perhaps if changing this one to PCI_UNKNOWN those three should those also > be PCI_UNKNOWN? > > Bjorn, Lukas, thoughts? > > > > > > > + return -EIO; > > > > + } > > > > + > > > > pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr); > > > > if (PCI_POSSIBLE_ERROR(pmcsr)) { > > > > pci_err(dev, "Unable to change power state from %s to D0, > > > > device inaccessible\n", Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> (I've no opinion on PCI_UNKNOWN or not.) -- i.
