[PATCH] PCI: qcom: avoid duplicate PERST# GPIO acquisition in legacy path
From: Kathiravan Thirumoorthy
Date: Tue May 26 2026 - 07:36:21 EST
Commit deed8aec62dc ("PCI: qcom: Handle mixed PERST#/PHY DT
configuration") handles the case where the PHY is moved to the Root
Port node while PERST# remains in the RC node by acquiring the PERST#
GPIO during Root Port parsing.
However, on platforms such as IPQ5424, both PERST# and PHY are
described under the RC node and are intended to be handled via the
legacy binding path. Since PERST# is already acquired during Root Port
parsing, attempting to acquire it again in the legacy path fails,
resulting in probe failures as shown below:
[ 1.571859] qcom-pcie 18000000.pcie: probe with driver qcom-pcie failed with error -16
[ 1.571909] qcom-pcie 10000000.pcie: probe with driver qcom-pcie failed with error -16
[ 1.571973] qcom-pcie 20000000.pcie: probe with driver qcom-pcie failed with error -16
Fix this by removing the redundant GPIO acquisition from
qcom_pcie_parse_legacy_binding() and reusing the PERST# descriptor
obtained in qcom_pcie_parse_ports().
While at it, move the warning message to qcom_pcie_parse_perst() to
avoid polluting dmesg when the legacy binding is used.
Fixes: deed8aec62dc ("PCI: qcom: Handle mixed PERST#/PHY DT configuration")
Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@xxxxxxxxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-qcom.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 11fc60489892..77cbd204ac5c 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -1824,6 +1824,7 @@ static int qcom_pcie_parse_perst(struct qcom_pcie *pcie,
int ret;
if (pcie->reset) {
+ dev_warn(dev, "Reusing PERST# from Root Complex node. DT needs to be fixed!\n");
reset = pcie->reset;
goto skip_perst_parsing;
}
@@ -1912,8 +1913,6 @@ static int qcom_pcie_parse_ports(struct qcom_pcie *pcie)
GPIOD_OUT_HIGH);
if (IS_ERR(pcie->reset))
return PTR_ERR(pcie->reset);
-
- dev_warn(dev, "Reusing PERST# from Root Complex node. DT needs to be fixed!\n");
}
for_each_available_child_of_node_scoped(dev->of_node, of_port) {
@@ -1942,7 +1941,6 @@ static int qcom_pcie_parse_legacy_binding(struct qcom_pcie *pcie)
struct device *dev = pcie->pci->dev;
struct qcom_pcie_perst *perst;
struct qcom_pcie_port *port;
- struct gpio_desc *reset;
struct phy *phy;
int ret;
@@ -1950,10 +1948,6 @@ static int qcom_pcie_parse_legacy_binding(struct qcom_pcie *pcie)
if (IS_ERR(phy))
return PTR_ERR(phy);
- reset = devm_gpiod_get_optional(dev, "perst", GPIOD_OUT_HIGH);
- if (IS_ERR(reset))
- return PTR_ERR(reset);
-
ret = phy_init(phy);
if (ret)
return ret;
@@ -1970,7 +1964,7 @@ static int qcom_pcie_parse_legacy_binding(struct qcom_pcie *pcie)
INIT_LIST_HEAD(&port->list);
list_add_tail(&port->list, &pcie->ports);
- perst->desc = reset;
+ perst->desc = pcie->reset;
INIT_LIST_HEAD(&port->perst);
INIT_LIST_HEAD(&perst->list);
list_add_tail(&perst->list, &port->perst);
---
base-commit: d387b06f7c15b4639244ad66b4b0900c6a02b430
change-id: 20260525-fix_perst_gpio_handling-5a4fee9228fd
Best regards,
--
Kathiravan Thirumoorthy <kathiravan.thirumoorthy@xxxxxxxxxxxxxxxx>