Re: [PATCH v2 07/15] scsi: hisi_sas_v3_hw: use generic power management

[Vaibhav Gupta]

On Mon, Jul 20, 2020 at 07:04:20PM +0530, Vaibhav Gupta wrote:
> With legacy PM, drivers themselves were responsible for managing the
> device's power states and takes care of register states.
> 
> After upgrading to the generic structure, PCI core will take care of
> required tasks and drivers should do only device-specific operations.
> 
> The driver was calling pci_save/restore_state(), pci_choose_state(),
> pci_enable/disable_device() and pci_set_power_state() which is no more
> needed.
> 
> Compile-tested only.
> 
> Signed-off-by: Vaibhav Gupta <vaibhavgupta40@xxxxxxxxx>
> ---
>  drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 32 +++++++++-----------------
>  1 file changed, 11 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
> index 55e2321a65bc..824bfbe1abbb 100644
> --- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
> +++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
> @@ -3374,13 +3374,13 @@ enum {
>  	hip08,
>  };
>  
> -static int hisi_sas_v3_suspend(struct pci_dev *pdev, pm_message_t state)
> +static int __maybe_unused hisi_sas_v3_suspend(struct device *dev_d)
>  {
> +	struct pci_dev *pdev = to_pci_dev(dev_d);
>  	struct sas_ha_struct *sha = pci_get_drvdata(pdev);
>  	struct hisi_hba *hisi_hba = sha->lldd_ha;
>  	struct device *dev = hisi_hba->dev;
>  	struct Scsi_Host *shost = hisi_hba->shost;
> -	pci_power_t device_state;
>  	int rc;
>  
>  	if (!pdev->pm_cap) {
> @@ -3406,12 +3406,7 @@ static int hisi_sas_v3_suspend(struct pci_dev *pdev, pm_message_t state)
>  
>  	hisi_sas_init_mem(hisi_hba);
>  
> -	device_state = pci_choose_state(pdev, state);
> -	dev_warn(dev, "entering operating state [D%d]\n",
> -			device_state);
> -	pci_save_state(pdev);
> -	pci_disable_device(pdev);
> -	pci_set_power_state(pdev, device_state);
> +	dev_warn(dev, "entering suspend state\n");
>  
>  	hisi_sas_release_tasks(hisi_hba);
>  
> @@ -3419,8 +3414,9 @@ static int hisi_sas_v3_suspend(struct pci_dev *pdev, pm_message_t state)
>  	return 0;
>  }
>  
> -static int hisi_sas_v3_resume(struct pci_dev *pdev)
> +static int __maybe_unused hisi_sas_v3_resume(struct device *dev_d)
>  {
> +	struct pci_dev *pdev = to_pci_dev(dev_d);
>  	struct sas_ha_struct *sha = pci_get_drvdata(pdev);
>  	struct hisi_hba *hisi_hba = sha->lldd_ha;
>  	struct Scsi_Host *shost = hisi_hba->shost;
> @@ -3430,16 +3426,8 @@ static int hisi_sas_v3_resume(struct pci_dev *pdev)
>  
>  	dev_warn(dev, "resuming from operating state [D%d]\n",
>  		 device_state);
> -	pci_set_power_state(pdev, PCI_D0);
> -	pci_enable_wake(pdev, PCI_D0, 0);
> -	pci_restore_state(pdev);
> -	rc = pci_enable_device(pdev);
> -	if (rc) {
> -		dev_err(dev, "enable device failed during resume (%d)\n", rc);
> -		return rc;
> -	}
> +	device_wakeup_disable(dev_d);
>  
> -	pci_set_master(pdev);
>  	scsi_unblock_requests(shost);
>  	clear_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags);
>  
> @@ -3447,7 +3435,6 @@ static int hisi_sas_v3_resume(struct pci_dev *pdev)
>  	rc = hw_init_v3_hw(hisi_hba);
>  	if (rc) {
>  		scsi_remove_host(shost);
> -		pci_disable_device(pdev);
>  		return rc;
>  	}
>  	hisi_hba->hw->phys_init(hisi_hba);
> @@ -3468,13 +3455,16 @@ static const struct pci_error_handlers hisi_sas_err_handler = {
>  	.reset_done	= hisi_sas_reset_done_v3_hw,
>  };
>  
> +static SIMPLE_DEV_PM_OPS(hisi_sas_v3_pm_ops,
> +			 hisi_sas_v3_suspend,
> +			 hisi_sas_v3_resume);
> +
>  static struct pci_driver sas_v3_pci_driver = {
>  	.name		= DRV_NAME,
>  	.id_table	= sas_v3_pci_table,
>  	.probe		= hisi_sas_v3_probe,
>  	.remove		= hisi_sas_v3_remove,
> -	.suspend	= hisi_sas_v3_suspend,
> -	.resume		= hisi_sas_v3_resume,
> +	.driver.pm	= &hisi_sas_v3_pm_ops,
>  	.err_handler	= &hisi_sas_err_handler,
>  };
>  
> -- 
> 2.27.0
> 
.