From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752554AbaAQJY0 (ORCPT ); Fri, 17 Jan 2014 04:24:26 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53793 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751567AbaAQJYT (ORCPT ); Fri, 17 Jan 2014 04:24:19 -0500 Date: Fri, 17 Jan 2014 10:26:20 +0100 From: Alexander Gordeev To: linux-kernel@vger.kernel.org Cc: linux-pci@vger.kernel.org, Tejun Heo Subject: [PATCH 10/9] PCI/MSI: Undeprecate pci_enable_msi() Message-ID: <20140117092620.GA29340@dhcp-26-207.brq.redhat.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Alexander Gordeev --- Documentation/PCI/MSI-HOWTO.txt | 23 ++++++++++++++++++++--- 1 files changed, 20 insertions(+), 3 deletions(-) diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt index a8d0100..3c3080e 100644 --- a/Documentation/PCI/MSI-HOWTO.txt +++ b/Documentation/PCI/MSI-HOWTO.txt @@ -82,7 +82,19 @@ Most of the hard work is done for the driver in the PCI layer. It simply has to request that the PCI layer set up the MSI capability for this device. -4.2.1 pci_enable_msi_range +4.2.1 pci_enable_msi + +int pci_enable_msi(struct pci_dev *dev) + +A successful call allocates ONE interrupt to the device, regardless +of how many MSIs the device supports. The device is switched from +pin-based interrupt mode to MSI mode. The dev->irq number is changed +to a new number which represents the message signaled interrupt; +consequently, this function should be called before the driver calls +request_irq(), because an MSI is delivered via a vector that is +different from the vector of a pin-based interrupt. + +4.2.2 pci_enable_msi_range int pci_enable_msi_range(struct pci_dev *dev, int minvec, int maxvec) @@ -158,7 +170,12 @@ static int foo_driver_enable_single_msi(struct pci_dev *pdev) return pci_enable_msi_range(pdev, 1, 1); } -4.2.2 pci_disable_msi +Note, unlike pci_enable_msi() function, which could be also used to +enable the single MSI mode, pci_enable_msi_range() returns either a +negative errno or 1 (not negative errno or 0 - as pci_enable_msi() +does). + +4.2.3 pci_disable_msi void pci_disable_msi(struct pci_dev *dev) @@ -172,7 +189,7 @@ on any interrupt for which it previously called request_irq(). Failure to do so results in a BUG_ON(), leaving the device with MSI enabled and thus leaking its vector. -4.2.3 pci_msi_vec_count +4.2.4 pci_msi_vec_count int pci_msi_vec_count(struct pci_dev *dev) -- 1.7.7.6 -- Regards, Alexander Gordeev agordeev@redhat.com