Re: [PATCH v2 4/8] PCI: brcmstb: Fix error path upon call of regulator_bulk_get()

On Tue, Mar 04, 2025 at 11:55:05AM -0500, Jim Quinlan wrote:

On Tue, Mar 4, 2025 at 10:03 AM Manivannan Sadhasivam
[off-list ref] wrote:

quoted

On Fri, Feb 14, 2025 at 12:39:32PM -0500, Jim Quinlan wrote:

quoted

If regulator_bulk_get() returns an error, no regulators are created and we
need to set their number to zero.  If we do not do this and the PCIe
link-up fails, regulator_bulk_free() will be invoked and effect a panic.

Also print out the error value, as we cannot return an error upwards as
Linux will WARN on an error from add_bus().

Fixes: 9e6be018b263 ("PCI: brcmstb: Enable child bus device regulators from DT")
Signed-off-by: Jim Quinlan <redacted>
---
 drivers/pci/controller/pcie-brcmstb.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index e0b20f58c604..56b49d3cae19 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c

@@ -1416,7 +1416,8 @@ static int brcm_pcie_add_bus(struct pci_bus *bus)

              ret = regulator_bulk_get(dev, sr->num_supplies, sr->supplies);
              if (ret) {
-                     dev_info(dev, "No regulators for downstream device\n");
+                     dev_info(dev, "Did not get regulators; err=%d\n", ret);

Why is this dev_info() instead of dev_err()?

I will change this.

quoted

quoted

+                     pcie->sr = NULL;

Why can't you set 'pcie->sr' after successfull regulator_bulk_get()?

Not sure I understand -- it is already set before a  successful
regulator_bulk_get() call.

Didn't I say 'after'?

I set it to NULL after an unsuccessful result so the structure will
not be passed to subsequent calls.

If you set the pointer after a successful regulator_bulk_get(), you do not need
to set it to NULL for a failure.

- Mani

-- 
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