Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755855Ab3DWHP6 (ORCPT ); Tue, 23 Apr 2013 03:15:58 -0400 Received: from g1t0028.austin.hp.com ([15.216.28.35]:29110 "EHLO g1t0028.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754872Ab3DWHP5 (ORCPT ); Tue, 23 Apr 2013 03:15:57 -0400 From: "Li, Zhen-Hua" To: , , , Cc: , "Li, Zhen-Hua" Subject: [PATCH 1/1] driver,usb: Fix a warning in uhci-hcd driver Date: Tue, 23 Apr 2013 15:15:01 +0800 Message-Id: <1366701301-16603-1-git-send-email-zhen-hual@hp.com> X-Mailer: git-send-email 1.7.10.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2033 Lines: 60 From: "Li, Zhen-Hua" This patch is trying to fix bug QXCR1001261767. On some HP platform, when usb driver inits the iLo Virtual USB Controller, there may be a warning "Controller not stopped yet!". It is because driver does not wait enough time. This patch adds more time waiting and retries. Signed-off-by: Li, Zhen-Hua --- drivers/usb/host/uhci-hcd.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c index 4a86b63..514e9d7 100644 --- a/drivers/usb/host/uhci-hcd.c +++ b/drivers/usb/host/uhci-hcd.c @@ -277,6 +277,9 @@ static int global_suspend_mode_is_broken(struct uhci_hcd *uhci) uhci->global_suspend_mode_is_broken(uhci) : 0; } +#define UHCI_SUSPENDRH_RETRY_MAX 10 +#define UHCI_SUSPENDRH_RETRY_DELAY 100 + static void suspend_rh(struct uhci_hcd *uhci, enum uhci_rh_state new_state) __releases(uhci->lock) __acquires(uhci->lock) @@ -284,6 +287,7 @@ __acquires(uhci->lock) int auto_stop; int int_enable, egsm_enable, wakeup_enable; struct usb_device *rhdev = uhci_to_hcd(uhci)->self.root_hub; + u16 try, stopped; auto_stop = (new_state == UHCI_RH_AUTO_STOPPED); dev_dbg(&rhdev->dev, "%s%s\n", __func__, @@ -355,7 +359,17 @@ __acquires(uhci->lock) if (uhci->dead) return; } - if (!(uhci_readw(uhci, USBSTS) & USBSTS_HCH)) + + for (try = 0; try < UHCI_SUSPENDRH_RETRY_MAX; try++) { + /* + * Sometimes we may need to wait more time and try again. + */ + stopped = uhci_readw(uhci, USBSTS) & USBSTS_HCH; + if (stopped) + break; + udelay(UHCI_SUSPENDRH_RETRY_DELAY); + } + if (!stopped) dev_warn(uhci_dev(uhci), "Controller not stopped yet!\n"); uhci_get_current_frame_number(uhci); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/