atyfb: Properly save PCI state before changing PCI PM level

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@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 15 insertions, 5 deletions

diff --git a/drivers/video/aty/atyfb_base.c b/drivers/video/aty/atyfb_base.c
index 1d6e16d346a5..1207c208a30b 100644
--- a/drivers/video/aty/atyfb_base.c
+++ b/drivers/video/aty/atyfb_base.c
@@ -1978,7 +1978,7 @@ static int aty_power_mgmt(int sleep, struct atyfb_par *par)
 
         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_dev *pdev, pm_message_t state)
         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_dev *pdev)
 
         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);