From: Wu Zhangjin <wuzhangjin@gmail.com>
To: linux-pm@lists.linux-foundation.org
Cc: linux-kernel@vger.kernel.org, len.brown@intel.com, pavel@ucw.cz,
zhangfx@lemote.com, wuzj@lemote.com, yanh@lemote.com,
Wu Zhangjin <wuzhangjin@gmail.com>
Subject: [PATCH] [suspend] pci_raw_set_power_state: replace msleep by udelay in resuming procedure
Date: Thu, 16 Jul 2009 23:43:27 +0800 [thread overview]
Message-ID: <1247759007-27411-1-git-send-email-wuzhangjin@gmail.com> (raw)
we can not call msleep() when resuming from STR/Standby: if the
current_state of the pci device is PCI_D3hot, means we are in the
procedure of resuming, in this procedure, we can not re-schedule,
otherwise, there will be a deadlock.
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
---
drivers/pci/pci.c | 12 +++++++++++-
1 files changed, 11 insertions(+), 1 deletions(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 440f4fb..3d9a4e2 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -497,8 +497,18 @@ static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
/* Mandatory power management transition delays */
/* see PCI PM 1.1 5.6.1 table 18 */
- if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
+
+ /* we can not call msleep() when resume:
+ *
+ * if the current_state is PCI_D3hot, means we are in the procedure
+ * of resuming, in this procedure, we can not re-schedule, otherwise,
+ * there will be a deadlock.
+ */
+
+ if (state == PCI_D3hot)
msleep(pci_pm_d3_delay);
+ else if (dev->current_state == PCI_D3hot)
+ udelay(pci_pm_d3_delay);
else if (state == PCI_D2 || dev->current_state == PCI_D2)
udelay(PCI_PM_D2_DELAY);
--
1.6.2.1
next reply other threads:[~2009-07-16 15:43 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-07-16 15:43 Wu Zhangjin [this message]
2009-07-16 17:02 ` [linux-pm] " Alan Stern
2009-07-17 2:10 ` Wu Zhangjin
2009-07-17 2:18 ` Wu Zhangjin
2009-07-17 2:33 ` Rafael J. Wysocki
2009-07-17 3:38 ` Wu Zhangjin
2009-07-22 2:23 ` Wu Zhangjin
2009-07-22 7:10 ` Pavel Machek
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