[PATCH 1/3] atyfb: Properly save PCI state before changing PCI PM level

From: Benjamin Herrenschmidt
Date: Wed Feb 04 2009 - 20:07:25 EST


This fixes atyfb to properly save the PCI config space -before- it
potentially switches the PM state of the chip. This avoids a
warning with the new PM core and is the right thing to do anyway.

I also slightly cleaned up the code that checks whether we are
running on a PowerMac to do a runtime check instead of a compile
check only, and replaced a deprecated number with the proper
symbolic constant.

Finally, I removed the useless switch to D0 from resume since
the core does it for us.

Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
---

drivers/video/aty/atyfb_base.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)

--- linux-work.orig/drivers/video/aty/atyfb_base.c 2009-02-04 13:10:22.000000000 +1100
+++ linux-work/drivers/video/aty/atyfb_base.c 2009-02-04 13:13:11.000000000 +1100
@@ -1978,7 +1978,7 @@ static int aty_power_mgmt(int sleep, str

return timeout ? 0 : -EIO;
}
-#endif
+#endif /* CONFIG_PPC_PMAC */

static int atyfb_pci_suspend(struct pci_dev *pdev, pm_message_t state)
{
@@ -2002,9 +2002,15 @@ static int atyfb_pci_suspend(struct pci_
par->asleep = 1;
par->lock_blank = 1;

+ /* Because we may change PCI D state ourselves, we need to
+ * first save the config space content so the core can
+ * restore it properly on resume.
+ */
+ pci_save_state(pdev);
+
#ifdef CONFIG_PPC_PMAC
/* Set chip to "suspend" mode */
- if (aty_power_mgmt(1, par)) {
+ if (machine_is(powermac) && aty_power_mgmt(1, par)) {
par->asleep = 0;
par->lock_blank = 0;
atyfb_blank(FB_BLANK_UNBLANK, info);
@@ -2047,11 +2053,15 @@ static int atyfb_pci_resume(struct pci_d

acquire_console_sem();

+ /* PCI state will have been restored by the core, so
+ * we should be in D0 now with our config space fully
+ * restored
+ */
+
#ifdef CONFIG_PPC_PMAC
- if (pdev->dev.power.power_state.event == 2)
+ if (machine_is(powermac) &&
+ pdev->dev.power.power_state.event == PM_EVENT_SUSPEND)
aty_power_mgmt(0, par);
-#else
- pci_set_power_state(pdev, PCI_D0);
#endif

aty_resume_chip(info);
--
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