Re: [PATCH v2 04/15] scsi: aic79xx: use generic power management

[Vaibhav Gupta]

On Mon, Jul 20, 2020 at 07:04:17PM +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.
> 
> Driver was 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.
> 
> Also, .suspend() and .resume() were invoking other functions for PM, which
> were againg bounded by "#ifdef CONFIG_PM" directive. Remove them and mark
> them as "__maybe_unused".
> 
> Compile-tested only.
> 
> Signed-off-by: Vaibhav Gupta <vaibhavgupta40@xxxxxxxxx>
> ---
>  drivers/scsi/aic7xxx/aic79xx.h         | 12 +++----
>  drivers/scsi/aic7xxx/aic79xx_core.c    |  8 ++---
>  drivers/scsi/aic7xxx/aic79xx_osm_pci.c | 43 +++++++-------------------
>  drivers/scsi/aic7xxx/aic79xx_pci.c     |  6 ++--
>  4 files changed, 20 insertions(+), 49 deletions(-)
> 
> diff --git a/drivers/scsi/aic7xxx/aic79xx.h b/drivers/scsi/aic7xxx/aic79xx.h
> index 9a515551641c..dd5dfd4f30a5 100644
> --- a/drivers/scsi/aic7xxx/aic79xx.h
> +++ b/drivers/scsi/aic7xxx/aic79xx.h
> @@ -1330,10 +1330,8 @@ const struct	ahd_pci_identity *ahd_find_pci_device(ahd_dev_softc_t);
>  int			  ahd_pci_config(struct ahd_softc *,
>  					 const struct ahd_pci_identity *);
>  int	ahd_pci_test_register_access(struct ahd_softc *);
> -#ifdef CONFIG_PM
> -void	ahd_pci_suspend(struct ahd_softc *);
> -void	ahd_pci_resume(struct ahd_softc *);
> -#endif
> +void __maybe_unused	ahd_pci_suspend(struct ahd_softc *);
> +void __maybe_unused	ahd_pci_resume(struct ahd_softc *);
>  
>  /************************** SCB and SCB queue management **********************/
>  void		ahd_qinfifo_requeue_tail(struct ahd_softc *ahd,
> @@ -1344,10 +1342,8 @@ struct ahd_softc	*ahd_alloc(void *platform_arg, char *name);
>  int			 ahd_softc_init(struct ahd_softc *);
>  void			 ahd_controller_info(struct ahd_softc *ahd, char *buf);
>  int			 ahd_init(struct ahd_softc *ahd);
> -#ifdef CONFIG_PM
> -int			 ahd_suspend(struct ahd_softc *ahd);
> -void			 ahd_resume(struct ahd_softc *ahd);
> -#endif
> +int __maybe_unused	 ahd_suspend(struct ahd_softc *ahd);
> +void __maybe_unused	 ahd_resume(struct ahd_softc *ahd);
>  int			 ahd_default_config(struct ahd_softc *ahd);
>  int			 ahd_parse_vpddata(struct ahd_softc *ahd,
>  					   struct vpd_config *vpd);
> diff --git a/drivers/scsi/aic7xxx/aic79xx_core.c b/drivers/scsi/aic7xxx/aic79xx_core.c
> index e4a09b93d00c..06ee7abd0f8f 100644
> --- a/drivers/scsi/aic7xxx/aic79xx_core.c
> +++ b/drivers/scsi/aic7xxx/aic79xx_core.c
> @@ -7880,11 +7880,9 @@ ahd_pause_and_flushwork(struct ahd_softc *ahd)
>  	ahd->flags &= ~AHD_ALL_INTERRUPTS;
>  }
>  
> -#ifdef CONFIG_PM
> -int
> +int __maybe_unused
>  ahd_suspend(struct ahd_softc *ahd)
>  {
> -
>  	ahd_pause_and_flushwork(ahd);
>  
>  	if (LIST_FIRST(&ahd->pending_scbs) != NULL) {
> @@ -7895,15 +7893,13 @@ ahd_suspend(struct ahd_softc *ahd)
>  	return (0);
>  }
>  
> -void
> +void __maybe_unused
>  ahd_resume(struct ahd_softc *ahd)
>  {
> -
>  	ahd_reset(ahd, /*reinit*/TRUE);
>  	ahd_intr_enable(ahd, TRUE); 
>  	ahd_restart(ahd);
>  }
> -#endif
>  
>  /************************** Busy Target Table *********************************/
>  /*
> diff --git a/drivers/scsi/aic7xxx/aic79xx_osm_pci.c b/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
> index 8b891a05d9e7..07b670b80f1b 100644
> --- a/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
> +++ b/drivers/scsi/aic7xxx/aic79xx_osm_pci.c
> @@ -74,11 +74,10 @@ static const struct pci_device_id ahd_linux_pci_id_table[] = {
>  
>  MODULE_DEVICE_TABLE(pci, ahd_linux_pci_id_table);
>  
> -#ifdef CONFIG_PM
> -static int
> -ahd_linux_pci_dev_suspend(struct pci_dev *pdev, pm_message_t mesg)
> +static int __maybe_unused
> +ahd_linux_pci_dev_suspend(struct device *dev)
>  {
> -	struct ahd_softc *ahd = pci_get_drvdata(pdev);
> +	struct ahd_softc *ahd = dev_get_drvdata(dev);
>  	int rc;
>  
>  	if ((rc = ahd_suspend(ahd)))
> @@ -86,39 +85,20 @@ ahd_linux_pci_dev_suspend(struct pci_dev *pdev, pm_message_t mesg)
>  
>  	ahd_pci_suspend(ahd);
>  
> -	pci_save_state(pdev);
> -	pci_disable_device(pdev);
> -
> -	if (mesg.event & PM_EVENT_SLEEP)
> -		pci_set_power_state(pdev, PCI_D3hot);
> -
>  	return rc;
>  }
>  
> -static int
> -ahd_linux_pci_dev_resume(struct pci_dev *pdev)
> +static int __maybe_unused
> +ahd_linux_pci_dev_resume(struct device *dev)
>  {
> -	struct ahd_softc *ahd = pci_get_drvdata(pdev);
> -	int rc;
> -
> -	pci_set_power_state(pdev, PCI_D0);
> -	pci_restore_state(pdev);
> -
> -	if ((rc = pci_enable_device(pdev))) {
> -		dev_printk(KERN_ERR, &pdev->dev,
> -			   "failed to enable device after resume (%d)\n", rc);
> -		return rc;
> -	}
> -
> -	pci_set_master(pdev);
> +	struct ahd_softc *ahd = dev_get_drvdata(dev);
>  
>  	ahd_pci_resume(ahd);
>  
>  	ahd_resume(ahd);
>  
> -	return rc;
> +	return 0;
>  }
> -#endif
>  
>  static void
>  ahd_linux_pci_dev_remove(struct pci_dev *pdev)
> @@ -224,13 +204,14 @@ ahd_linux_pci_dev_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	return (0);
>  }
>  
> +static SIMPLE_DEV_PM_OPS(ahd_linux_pci_dev_pm_ops,
> +			 ahd_linux_pci_dev_suspend,
> +			 ahd_linux_pci_dev_resume);
> +
>  static struct pci_driver aic79xx_pci_driver = {
>  	.name		= "aic79xx",
>  	.probe		= ahd_linux_pci_dev_probe,
> -#ifdef CONFIG_PM
> -	.suspend	= ahd_linux_pci_dev_suspend,
> -	.resume		= ahd_linux_pci_dev_resume,
> -#endif
> +	.driver.pm	= &ahd_linux_pci_dev_pm_ops,
>  	.remove		= ahd_linux_pci_dev_remove,
>  	.id_table	= ahd_linux_pci_id_table
>  };
> diff --git a/drivers/scsi/aic7xxx/aic79xx_pci.c b/drivers/scsi/aic7xxx/aic79xx_pci.c
> index 8397ae93f7dd..2f0bdb9225a4 100644
> --- a/drivers/scsi/aic7xxx/aic79xx_pci.c
> +++ b/drivers/scsi/aic7xxx/aic79xx_pci.c
> @@ -377,8 +377,7 @@ ahd_pci_config(struct ahd_softc *ahd, const struct ahd_pci_identity *entry)
>  	return ahd_pci_map_int(ahd);
>  }
>  
> -#ifdef CONFIG_PM
> -void
> +void __maybe_unused
>  ahd_pci_suspend(struct ahd_softc *ahd)
>  {
>  	/*
> @@ -394,7 +393,7 @@ ahd_pci_suspend(struct ahd_softc *ahd)
>  
>  }
>  
> -void
> +void __maybe_unused
>  ahd_pci_resume(struct ahd_softc *ahd)
>  {
>  	ahd_pci_write_config(ahd->dev_softc, DEVCONFIG,
> @@ -404,7 +403,6 @@ ahd_pci_resume(struct ahd_softc *ahd)
>  	ahd_pci_write_config(ahd->dev_softc, CSIZE_LATTIME,
>  			     ahd->suspend_state.pci_state.csize_lattime, /*bytes*/1);
>  }
> -#endif
>  
>  /*
>   * Perform some simple tests that should catch situations where
> -- 
> 2.27.0
> 
.