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author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2009-03-20 09:22:30 +1100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-03-22 11:08:53 -0700 |
commit | 18a0d89e54ca0f6f33582f99ae39867b2c975559 (patch) | |
tree | 6698711fdad0ded22c69b1e83d2984ffaf70cb96 /drivers | |
parent | 65c24491b4fef017c64e39ec64384fde5e05e0a0 (diff) | |
download | linux-3.10-18a0d89e54ca0f6f33582f99ae39867b2c975559.tar.gz linux-3.10-18a0d89e54ca0f6f33582f99ae39867b2c975559.tar.bz2 linux-3.10-18a0d89e54ca0f6f33582f99ae39867b2c975559.zip |
radeonfb: Whack the PCI PM register until it sticks
This fixes a regression introduced when we switched to using the core
pci_set_power_state(). The chip seems to need the state to be written
over and over again until it sticks, so we do that.
Note that the code is a bit blunt, without timeout, etc... but that's
pretty much because I put back in there the code exactly as it used to
be before the regression. I still add a call to pci_set_power_state()
at the end so that ACPI gets called appropriately on x86.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Raymond Wooninck <tittiatcoke@gmail.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/video/aty/radeon_pm.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/video/aty/radeon_pm.c b/drivers/video/aty/radeon_pm.c index 81603f85e17..c6d7cc76516 100644 --- a/drivers/video/aty/radeon_pm.c +++ b/drivers/video/aty/radeon_pm.c @@ -2507,6 +2507,25 @@ static void radeon_reinitialize_QW(struct radeonfb_info *rinfo) #endif /* CONFIG_PPC_OF */ +static void radeonfb_whack_power_state(struct radeonfb_info *rinfo, pci_power_t state) +{ + u16 pwr_cmd; + + for (;;) { + pci_read_config_word(rinfo->pdev, + rinfo->pm_reg+PCI_PM_CTRL, + &pwr_cmd); + if (pwr_cmd & 2) + break; + pwr_cmd = (pwr_cmd & ~PCI_PM_CTRL_STATE_MASK) | 2; + pci_write_config_word(rinfo->pdev, + rinfo->pm_reg+PCI_PM_CTRL, + pwr_cmd); + msleep(500); + } + rinfo->pdev->current_state = state; +} + static void radeon_set_suspend(struct radeonfb_info *rinfo, int suspend) { u32 tmp; @@ -2558,6 +2577,11 @@ static void radeon_set_suspend(struct radeonfb_info *rinfo, int suspend) /* Switch PCI power management to D2. */ pci_disable_device(rinfo->pdev); pci_save_state(rinfo->pdev); + /* The chip seems to need us to whack the PM register + * repeatedly until it sticks. We do that -prior- to + * calling pci_set_power_state() + */ + radeonfb_whack_power_state(rinfo, PCI_D2); pci_set_power_state(rinfo->pdev, PCI_D2); } else { printk(KERN_DEBUG "radeonfb (%s): switching to D0 state...\n", |