PCI: brcmstb: Disable/enable regulators in suspend/resume

If we found power regulators for a device below the Root Port, disable them
during suspend and re-enable them during resume.

If any downstream device can be a wakeup device, do not turn off the
regulators as the device will need them on.

[bhelgaas: drop unused regulator_oops, skip wrapping of .add_bus()/
.remove_bus(), move brcm_pcie_start_link() to .add_bus() in previous patch,
squash WOL checking into this patch]
Link: https://lore.kernel.org/r/20220725151258.42574-6-jim2101024@gmail.com
Link: https://lore.kernel.org/r/20220725151258.42574-7-jim2101024@gmail.com
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
This commit is contained in:
Jim Quinlan 2022-07-25 11:12:54 -04:00 committed by Bjorn Helgaas
parent 9e6be018b2
commit 7a32e9b3ff
1 changed files with 59 additions and 5 deletions

View File

@ -262,6 +262,7 @@ struct brcm_pcie {
void (*perst_set)(struct brcm_pcie *pcie, u32 val);
void (*bridge_sw_init_set)(struct brcm_pcie *pcie, u32 val);
struct subdev_regulators *sr;
bool ep_wakeup_capable;
};
static inline bool is_bmips(const struct brcm_pcie *pcie)
@ -1244,9 +1245,21 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie)
pcie->bridge_sw_init_set(pcie, 1);
}
static int brcm_pcie_suspend(struct device *dev)
static int pci_dev_may_wakeup(struct pci_dev *dev, void *data)
{
bool *ret = data;
if (device_may_wakeup(&dev->dev)) {
*ret = true;
dev_info(&dev->dev, "Possible wake-up device; regulators will not be disabled\n");
}
return (int) *ret;
}
static int brcm_pcie_suspend_noirq(struct device *dev)
{
struct brcm_pcie *pcie = dev_get_drvdata(dev);
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
int ret;
brcm_pcie_turn_off(pcie);
@ -1264,12 +1277,31 @@ static int brcm_pcie_suspend(struct device *dev)
return ret;
}
if (pcie->sr) {
/*
* Now turn off the regulators, but if at least one
* downstream device is enabled as a wake-up source, do not
* turn off regulators.
*/
pcie->ep_wakeup_capable = false;
pci_walk_bus(bridge->bus, pci_dev_may_wakeup,
&pcie->ep_wakeup_capable);
if (!pcie->ep_wakeup_capable) {
ret = regulator_bulk_disable(pcie->sr->num_supplies,
pcie->sr->supplies);
if (ret) {
dev_err(dev, "Could not turn off regulators\n");
reset_control_reset(pcie->rescal);
return ret;
}
}
}
clk_disable_unprepare(pcie->clk);
return 0;
}
static int brcm_pcie_resume(struct device *dev)
static int brcm_pcie_resume_noirq(struct device *dev)
{
struct brcm_pcie *pcie = dev_get_drvdata(dev);
void __iomem *base;
@ -1304,15 +1336,37 @@ static int brcm_pcie_resume(struct device *dev)
if (ret)
goto err_reset;
if (pcie->sr) {
if (pcie->ep_wakeup_capable) {
/*
* We are resuming from a suspend. In the suspend we
* did not disable the power supplies, so there is
* no need to enable them (and falsely increase their
* usage count).
*/
pcie->ep_wakeup_capable = false;
} else {
ret = regulator_bulk_enable(pcie->sr->num_supplies,
pcie->sr->supplies);
if (ret) {
dev_err(dev, "Could not turn on regulators\n");
goto err_reset;
}
}
}
ret = brcm_pcie_start_link(pcie);
if (ret)
goto err_reset;
goto err_regulator;
if (pcie->msi)
brcm_msi_set_regs(pcie->msi);
return 0;
err_regulator:
if (pcie->sr)
regulator_bulk_disable(pcie->sr->num_supplies, pcie->sr->supplies);
err_reset:
reset_control_rearm(pcie->rescal);
err_disable_clk:
@ -1541,8 +1595,8 @@ fail:
MODULE_DEVICE_TABLE(of, brcm_pcie_match);
static const struct dev_pm_ops brcm_pcie_pm_ops = {
.suspend = brcm_pcie_suspend,
.resume = brcm_pcie_resume,
.suspend_noirq = brcm_pcie_suspend_noirq,
.resume_noirq = brcm_pcie_resume_noirq,
};
static struct platform_driver brcm_pcie_driver = {