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Date: Wed, 20 Nov 2013 11:18:08 -0500
From: Tejun Heo <tj@kernel.org>
To: Alexander Gordeev <agordeev@redhat.com>
Cc: linux-kernel@vger.kernel.org, Bjorn Helgaas <bhelgaas@google.com>,
	Michael Ellerman <michael@ellerman.id.au>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Ben Hutchings <bhutchings@solarflare.com>,
	David Laight <David.Laight@ACULAB.COM>,
	Mark Lord <kernel@start.ca>, "H. Peter Anvin" <hpa@zytor.com>,
	linux-pci@vger.kernel.org
Subject: Re: [PATCH RFC v2 09/29] PCI/MSI: Factor out pci_get_msi_cap()
 interface
Message-ID: <20131120161808.GI28946@htj.dyndns.org>
References: <cover.1382103786.git.agordeev@redhat.com>
 <85500e7239fcb104df091bbfa873eef8ae654772.1382103786.git.agordeev@redhat.com>
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Hello,

On Fri, Oct 18, 2013 at 07:12:09PM +0200, Alexander Gordeev wrote:
> +If this function returns a negative number, it indicates the device is
> +not capable of sending MSIs.

Wouldn't "errno" better describe the error return rather than
"negative number"?

> @@ -795,6 +795,21 @@ static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type)
>  	return 0;
>  }

We probably want a function comment here?

> +int pci_get_msi_cap(struct pci_dev *dev)
> +{
> +	int ret;
> +	u16 msgctl;
> +
> +	if (!dev->msi_cap)
> +		return -EINVAL;
> +
> +	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl);
> +	ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL(pci_get_msi_cap);

Other than that,

 Reviewed-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun