On Wed, Mar 14, 2018 at 12:41 PM, Mika Westerberg
<mika.westerberg@xxxxxxxxxxxxxxx> wrote:
> When system is resumed if the interrupt generation is enabled it may
> trigger immediately when interrupts are enabled depending on what is in
> the status register. This may generate spurious DPC conditions and
> unnecessary removal of devices.
>
> Make this work better with system suspend and disable interrupt
> generation when the system is suspended.
>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> ---
> drivers/pci/pcie/pcie-dpc.c | 29 +++++++++++++++++++++++++----
> 1 file changed, 25 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c
> index 38e40c6c576f..14b96983dbbd 100644
> --- a/drivers/pci/pcie/pcie-dpc.c
> +++ b/drivers/pci/pcie/pcie-dpc.c
> @@ -280,23 +280,44 @@ static int dpc_probe(struct pcie_device *dev)
> return status;
> }
>
> -static void dpc_remove(struct pcie_device *dev)
> +static void dpc_interrupt_enable(struct dpc_dev *dpc, bool enable)
> {
> - struct dpc_dev *dpc = get_service_data(dev);
> - struct pci_dev *pdev = dev->port;
> + struct pci_dev *pdev = dpc->dev->port;
> u16 ctl;
>
> pci_read_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, &ctl);
> - ctl &= ~(PCI_EXP_DPC_CTL_EN_NONFATAL | PCI_EXP_DPC_CTL_INT_EN);
> + if (enable)
> + ctl |= PCI_EXP_DPC_CTL_EN_NONFATAL | PCI_EXP_DPC_CTL_INT_EN;
> + else
> + ctl &= ~(PCI_EXP_DPC_CTL_EN_NONFATAL | PCI_EXP_DPC_CTL_INT_EN);
> pci_write_config_word(pdev, dpc->cap_pos + PCI_EXP_DPC_CTL, ctl);
> }
>
> +static void dpc_remove(struct pcie_device *dev)
> +{
> + dpc_interrupt_enable(get_service_data(dev), false);
> +}
> +
> +static int dpc_suspend(struct pcie_device *dev)
> +{
> + dpc_interrupt_enable(get_service_data(dev), false);
> + return 0;
> +}
> +
> +static int dpc_resume(struct pcie_device *dev)
> +{
> + dpc_interrupt_enable(get_service_data(dev), true);
> + return 0;
> +}
Have you considered putting these things into the ->suspend_late and
->resume_early callbacks, respectively?
That might be slightly better as runtime resume is still enabled when
the ->suspend and ->resume callbacks run.
> +
> static struct pcie_port_service_driver dpcdriver = {
> .name = "dpc",
> .port_type = PCIE_ANY_PORT,
> .service = PCIE_PORT_SERVICE_DPC,
> .probe = dpc_probe,
> .remove = dpc_remove,
> + .suspend = dpc_suspend,
> + .resume = dpc_resume,
> };
>
> static int __init dpc_service_init(void)
> --
--
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
