[PATCH v6 04/13] PCI: tegra194: Disable PERST IRQ only in Endpoint mode

[Manikanta Maddireddy <mmaddireddy@nvidia.com>]

The PERST (PERST#) GPIO interrupt is only registered when the controller
is operating in Endpoint mode. In Root Port mode, the PERST GPIO is
configured as an output to control downstream devices, and no interrupt
is registered for it.

Currently, tegra_pcie_dw_stop_link() unconditionally calls disable_irq()
on pex_rst_irq, which causes issues in Root Port mode where this IRQ is
not registered.

Fix this by only disabling the PERST IRQ when operating in Endpoint mode,
where the interrupt is actually registered and used to detect PERST
assertion/deassertion from the host.

Fixes: c57247f940e8 ("PCI: tegra: Add support for PCIe endpoint mode in Tegra194")
Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
---
Changes V1 -> V6: None

 drivers/pci/controller/dwc/pcie-tegra194.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 808a1e213b79..9455456028bc 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1028,7 +1028,8 @@ static void tegra_pcie_dw_stop_link(struct dw_pcie *pci)
 {
 	struct tegra_pcie_dw *pcie = to_tegra_pcie(pci);
 
-	disable_irq(pcie->pex_rst_irq);
+	if (pcie->of_data->mode == DW_PCIE_EP_TYPE)
+		disable_irq(pcie->pex_rst_irq);
 }
 
 static const struct dw_pcie_ops tegra_dw_pcie_ops = {
-- 
2.34.1