Re: [PATCH v2 1/2] PCI: Disable MSI for Pericom PCIe-USB adapter

[Bjorn Helgaas <helgaas@kernel.org>]

On Fri, Nov 06, 2020 at 12:05:25PM +0200, Andy Shevchenko wrote:
> Pericom PCIe-USB adapter advertises MSI, but documentation says
> "The MSI Function is not implemented on this device." in the chapters
> 7.3.27, 7.3.29-7.3.31.
> 
> Fixes: 306c54d0edb6 ("usb: hcd: Try MSI interrupts on PCI devices")
> Datasheet: https://www.diodes.com/assets/Datasheets/PI7C9X440SL.pdf
> Reported-by: alberto.vignani@fastwebnet.it

Is there a URL to a problem report we can include here?

> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> v2: dropped confusing word (David), added ifdeffery (Ben)
>  drivers/pci/quirks.c | 17 +++++++++++++----
>  1 file changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index f70692ac79c5..e66e0cc8f99b 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -5567,17 +5567,26 @@ static void pci_fixup_no_d0_pme(struct pci_dev *dev)
>  DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ASMEDIA, 0x2142, pci_fixup_no_d0_pme);
>  
>  /*
> - * Device [12d8:0x400e] and [12d8:0x400f]
> + * Device 12d8:0x400e [OHCI] and 12d8:0x400f [EHCI]
> + *
>   * These devices advertise PME# support in all power states but don't
>   * reliably assert it.
> + *
> + * These devices advertise MSI, but documentation (PI7C9X440SL.pdf) says
> + * "The MSI Function is not implemented on this device." in the chapters
> + * 7.3.27, 7.3.29-7.3.31.
>   */
> -static void pci_fixup_no_pme(struct pci_dev *dev)
> +static void pci_fixup_no_msi_no_pme(struct pci_dev *dev)
>  {
> +#ifdef CONFIG_PCI_MSI
> +	pci_info(dev, "The MSI is not implemented on this device, disabling it\n");
> +	dev->no_msi = 1;
> +#endif
>  	pci_info(dev, "PME# is unreliable, disabling it\n");
>  	dev->pme_support = 0;
>  }
> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400e, pci_fixup_no_pme);
> -DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400f, pci_fixup_no_pme);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400e, pci_fixup_no_msi_no_pme);
> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400f, pci_fixup_no_msi_no_pme);
>  
>  static void apex_pci_fixup_class(struct pci_dev *pdev)
>  {
> -- 
> 2.28.0
>