PCI: Enable INTx if BIOS left them disabled
Some firmware leaves the Interrupt Disable bit set even if the device uses INTx interrupts. Clear Interrupt Disable so we get those interrupts. Based on the report mentioned below, if the user selects the "EHCI only" option in the Intel Baytrail BIOS, the EHCI device is handed off to the OS with the PCI_COMMAND_INTX_DISABLE bit set. Link: http://lkml.kernel.org/r/20140114181721.GC12126@xanatos Link: https://bugzilla.kernel.org/show_bug.cgi?id=70601 Reported-by: Chris Cheng <chris.cheng@atrustcorp.com> Reported-and-tested-by: Jamie Chen <jamie.chen@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
This commit is contained in:
parent
058a2e1bb0
commit
1e2571a781
|
@ -1181,6 +1181,8 @@ EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state);
|
|||
static int do_pci_enable_device(struct pci_dev *dev, int bars)
|
||||
{
|
||||
int err;
|
||||
u16 cmd;
|
||||
u8 pin;
|
||||
|
||||
err = pci_set_power_state(dev, PCI_D0);
|
||||
if (err < 0 && err != -EIO)
|
||||
|
@ -1190,6 +1192,14 @@ static int do_pci_enable_device(struct pci_dev *dev, int bars)
|
|||
return err;
|
||||
pci_fixup_device(pci_fixup_enable, dev);
|
||||
|
||||
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
|
||||
if (pin) {
|
||||
pci_read_config_word(dev, PCI_COMMAND, &cmd);
|
||||
if (cmd & PCI_COMMAND_INTX_DISABLE)
|
||||
pci_write_config_word(dev, PCI_COMMAND,
|
||||
cmd & ~PCI_COMMAND_INTX_DISABLE);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in a new issue