[PATCH AUTOSEL 5.17 53/60] Revert "PCI: brcmstb: Do not turn off WOL regulators on suspend"

Sasha Levin
2022-06-07T19:18:11Z

From: Bjorn Helgaas <bhelgaas@google.com>

[ Upstream commit 7894025c783ca36394d3afe49c8cfb4c830b82fe ]

This reverts commit 11ed8b8624b8085f706864b4addcd304b1e4fc38.

This is part of a revert of the following commits:

11ed8b8624b8 ("PCI: brcmstb: Do not turn off WOL regulators on suspend")
93e41f3fca3d ("PCI: brcmstb: Add control of subdevice voltage regulators")
67211aadcb4b ("PCI: brcmstb: Add mechanism to turn on subdev regulators")
830aa6f29f07 ("PCI: brcmstb: Split brcm_pcie_setup() into two funcs")

Cyril reported that 830aa6f29f07 ("PCI: brcmstb: Split brcm_pcie_setup()
into two funcs"), which appeared in v5.17-rc1, broke booting on the
Raspberry Pi Compute Module 4. Apparently 830aa6f29f07 panics with an
Asynchronous SError Interrupt, and after further commits here is a black
screen on HDMI and no output on the serial console.

This does not seem to affect the Raspberry Pi 4 B.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215925
Link: https://lore.kernel.org/r/20220511201856.808690-2-helgaas@kernel.org
Reported-by: Cyril Brulebois <kibi@debian.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/controller/pcie-brcmstb.c | 53 +++++----------------------
1 file changed, 9 insertions(+), 44 deletions(-)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 375c0c40bbf8..3edd63735948 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -333,7 +333,6 @@ struct brcm_pcie {
void (*bridge_sw_init_set)(struct brcm_pcie *pcie, u32 val);
bool refusal_mode;
struct subdev_regulators *sr;
- bool ep_wakeup_capable;
};

static inline bool is_bmips(const struct brcm_pcie *pcie)
@@ -1351,21 +1350,9 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie)
pcie->bridge_sw_init_set(pcie, 1);
}

-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, "disable cancelled for wake-up device\n");
- }
- return (int) *ret;
-}
-
static int brcm_pcie_suspend(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);
@@ -1384,22 +1371,11 @@ static int brcm_pcie_suspend(struct device *dev)
}

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;
- }
+ 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);
@@ -1420,21 +1396,10 @@ static int brcm_pcie_resume(struct device *dev)
return ret;

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_disable_clk;
- }
+ ret = regulator_bulk_enable(pcie->sr->num_supplies, pcie->sr->supplies);
+ if (ret) {
+ dev_err(dev, "Could not turn on regulators\n");
+ goto err_disable_clk;
}
}

--
2.35.1