From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756089AbaCYRqY (ORCPT ); Tue, 25 Mar 2014 13:46:24 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:55808 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754869AbaCYRVN (ORCPT ); Tue, 25 Mar 2014 13:21:13 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Bjorn Helgaas , Sarah Sharp , Kamal Mostafa Subject: [PATCH 3.8 23/81] PCI: Enable INTx if BIOS left them disabled Date: Tue, 25 Mar 2014 10:15:36 -0700 Message-Id: <1395767794-5012-24-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1395767794-5012-1-git-send-email-kamal@canonical.com> References: <1395767794-5012-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.8.13.20 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Bjorn Helgaas commit 1f42db786b14a31bf807fc41ee5583a00c08fcb1 upstream. Some firmware leaves the Interrupt Disable bit set even if the device uses INTx interrupts. Clear Interrupt Disable so we get those interrupts. Based on the report mentioned below, if the user selects the "EHCI only" option in the Intel Baytrail BIOS, the EHCI device is handed off to the OS with the PCI_COMMAND_INTX_DISABLE bit set. Link: http://lkml.kernel.org/r/20140114181721.GC12126@xanatos Link: https://bugzilla.kernel.org/show_bug.cgi?id=70601 Reported-by: Chris Cheng Reported-and-tested-by: Jamie Chen Signed-off-by: Bjorn Helgaas CC: Sarah Sharp Signed-off-by: Kamal Mostafa --- drivers/pci/pci.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index d1b4e00..4235728 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1126,6 +1126,8 @@ EXPORT_SYMBOL_GPL(pci_load_and_free_saved_state); static int do_pci_enable_device(struct pci_dev *dev, int bars) { int err; + u16 cmd; + u8 pin; err = pci_set_power_state(dev, PCI_D0); if (err < 0 && err != -EIO) @@ -1135,6 +1137,14 @@ static int do_pci_enable_device(struct pci_dev *dev, int bars) return err; pci_fixup_device(pci_fixup_enable, dev); + pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin); + if (pin) { + pci_read_config_word(dev, PCI_COMMAND, &cmd); + if (cmd & PCI_COMMAND_INTX_DISABLE) + pci_write_config_word(dev, PCI_COMMAND, + cmd & ~PCI_COMMAND_INTX_DISABLE); + } + return 0; } -- 1.8.3.2