Commit 18a0d89e authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Linus Torvalds

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: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: default avatarRaymond Wooninck <tittiatcoke@gmail.com>
Acked-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 65c24491
......@@ -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",
......
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