On Mon, Jul 20, 2020 at 07:04:14PM +0530, Vaibhav Gupta wrote:
> With legacy PM hooks, it was the responsibility of a driver to manage PCI
> states and also the device's power state. The generic approach is to let
> the PCI core handle the work.
>
> PCI core passes "struct device*" as an argument to the .suspend() and
> .resume() callbacks. As the .suspend() work with "struct instance*",
> extract it from "struct device*" using dev_get_drv_data().
>
> Driver was also using PCI helper functions like pci_save/restore_state(),
> pci_disable/enable_device(), pci_set_power_state() and pci_enable_wake().
> They should not be invoked by the driver.
>
> Compile-tested only.
>
> Signed-off-by: Vaibhav Gupta <vaibhavgupta40@xxxxxxxxx>
> ---
> drivers/scsi/megaraid/megaraid_sas_base.c | 61 ++++++-----------------
> 1 file changed, 16 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
> index 00668335c2af..4a6ee7778977 100644
> --- a/drivers/scsi/megaraid/megaraid_sas_base.c
> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c
> @@ -7539,25 +7539,21 @@ static void megasas_shutdown_controller(struct megasas_instance *instance,
> megasas_return_cmd(instance, cmd);
> }
>
> -#ifdef CONFIG_PM
> /**
> * megasas_suspend - driver suspend entry point
> - * @pdev: PCI device structure
> - * @state: PCI power state to suspend routine
> + * @dev: Device structure
> */
> -static int
> -megasas_suspend(struct pci_dev *pdev, pm_message_t state)
> +static int __maybe_unused
> +megasas_suspend(struct device *dev)
> {
> - struct megasas_instance *instance;
> -
> - instance = pci_get_drvdata(pdev);
> + struct megasas_instance *instance = dev_get_drvdata(dev);
>
> if (!instance)
> return 0;
>
> instance->unload = 1;
>
> - dev_info(&pdev->dev, "%s is called\n", __func__);
> + dev_info(dev, "%s is called\n", __func__);
>
> /* Shutdown SR-IOV heartbeat timer */
> if (instance->requestorId && !instance->skip_heartbeat_timer_del)
> @@ -7579,7 +7575,7 @@ megasas_suspend(struct pci_dev *pdev, pm_message_t state)
>
> tasklet_kill(&instance->isr_tasklet);
>
> - pci_set_drvdata(instance->pdev, instance);
> + dev_set_drvdata(dev, instance);
It *might* be correct to replace "instance->pdev" with "dev", but it's
not obvious and deserves some explanation. It's true that you can
replace &pdev->dev with dev, but I don't know anything about
instance->dev.
I don't think this change is actually necessary, is it?
"instance->pdev" is still a pci_dev pointer, so pci_set_drvdata()
should work fine.
It looks goofy to use pci_set_drvdata() or dev_set_drvdata() in a
suspend routine, but I didn't bother trying to figure out what's going
on here.
> instance->instancet->disable_intr(instance);
>
> megasas_destroy_irqs(instance);
> @@ -7587,48 +7583,28 @@ megasas_suspend(struct pci_dev *pdev, pm_message_t state)
> if (instance->msix_vectors)
> pci_free_irq_vectors(instance->pdev);
>
> - pci_save_state(pdev);
> - pci_disable_device(pdev);
> -
> - pci_set_power_state(pdev, pci_choose_state(pdev, state));
> -
> return 0;
> }
>
> /**
> * megasas_resume- driver resume entry point
> - * @pdev: PCI device structure
> + * @dev: Device structure
> */
> -static int
> -megasas_resume(struct pci_dev *pdev)
> +static int __maybe_unused
> +megasas_resume(struct device *dev)
> {
> int rval;
> struct Scsi_Host *host;
> - struct megasas_instance *instance;
> + struct megasas_instance *instance = dev_get_drvdata(dev);
> u32 status_reg;
>
> - instance = pci_get_drvdata(pdev);
> -
> if (!instance)
> return 0;
>
> host = instance->host;
> - pci_set_power_state(pdev, PCI_D0);
> - pci_enable_wake(pdev, PCI_D0, 0);
> - pci_restore_state(pdev);
> + device_wakeup_disable(dev);
Shouldn't there be a corresponding device_wakeup_enable() or similar
elsewhere?
Maybe the fact that megasas disables wakeup but never enables it is a
latent bug?
> - dev_info(&pdev->dev, "%s is called\n", __func__);
> - /*
> - * PCI prepping: enable device set bus mastering and dma mask
> - */
> - rval = pci_enable_device_mem(pdev);
> -
> - if (rval) {
> - dev_err(&pdev->dev, "Enable device failed\n");
> - return rval;
> - }
> -
> - pci_set_master(pdev);
> + dev_info(dev, "%s is called\n", __func__);
>
> /*
> * We expect the FW state to be READY
> @@ -7754,14 +7730,8 @@ megasas_resume(struct pci_dev *pdev)
> fail_set_dma_mask:
> fail_ready_state:
>
> - pci_disable_device(pdev);
> -
> return -ENODEV;
> }
> -#else
> -#define megasas_suspend NULL
> -#define megasas_resume NULL
> -#endif
>
> static inline int
> megasas_wait_for_adapter_operational(struct megasas_instance *instance)
> @@ -7931,7 +7901,7 @@ static void megasas_detach_one(struct pci_dev *pdev)
>
> /**
> * megasas_shutdown - Shutdown entry point
> - * @device: Generic device structure
> + * @pdev: PCI device structure
Looks like an unrelated typo fix? I would put this in a separate
patch.
> */
> static void megasas_shutdown(struct pci_dev *pdev)
> {
> @@ -8508,6 +8478,8 @@ static const struct file_operations megasas_mgmt_fops = {
> .llseek = noop_llseek,
> };
>
> +static SIMPLE_DEV_PM_OPS(megasas_pm_ops, megasas_suspend, megasas_resume);
> +
> /*
> * PCI hotplug support registration structure
> */
> @@ -8517,8 +8489,7 @@ static struct pci_driver megasas_pci_driver = {
> .id_table = megasas_pci_table,
> .probe = megasas_probe_one,
> .remove = megasas_detach_one,
> - .suspend = megasas_suspend,
> - .resume = megasas_resume,
> + .driver.pm = &megasas_pm_ops,
> .shutdown = megasas_shutdown,
> };
>
> --
> 2.27.0
>
