Re: [PATCH 2.6.32 v3] Conditional MSI support for sata_nv

[Jeff Garzik <jgarzik@pobox.com>]

Tony Vroon wrote:
> At least the nVidia MCP55 controller quite happily supports MSI.
> This adds an option to use it. It is disabled by default.
> As per feedback by Robert Hancock, it will honour the user 
> request as the kernel will not enable MSI where the controller 
> or the specific system configuration do not support it.
> 
> Signed-off-by: Tony Vroon <tony@linx.net>
> Cc: Robert Hancock <hancockrwd@gmail.com>
> 
> diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
> index b2d11f3..4598f19 100644
> --- a/drivers/ata/sata_nv.c
> +++ b/drivers/ata/sata_nv.c
> @@ -602,6 +602,7 @@ MODULE_VERSION(DRV_VERSION);
>  
>  static int adma_enabled;
>  static int swncq_enabled = 1;
> +static int msi_enabled;
>  
>  static void nv_adma_register_mode(struct ata_port *ap)
>  {
> @@ -2459,6 +2460,12 @@ static int nv_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	} else if (type == SWNCQ)
>  		nv_swncq_host_init(host);
>  
> +	if (msi_enabled) {
> +		dev_printk(KERN_NOTICE, &pdev->dev, "Using MSI\n");
> +		pci_enable_msi(pdev);
> +	}
> +
>  	pci_set_master(pdev);
>  	return ata_host_activate(host, pdev->irq, ipriv->irq_handler,
>  				 IRQF_SHARED, ipriv->sht);
> @@ -2558,4 +2565,6 @@ module_param_named(adma, adma_enabled, bool, 0444);
>  MODULE_PARM_DESC(adma, "Enable use of ADMA (Default: false)");
>  module_param_named(swncq, swncq_enabled, bool, 0444);
>  MODULE_PARM_DESC(swncq, "Enable use of SWNCQ (Default: true)");

applied