[PATCH] PCI: imx6: fix power domain leak on probe failure

imx_pcie_attach_pd() attaches the "pcie" and "pcie_phy" power domains
and creates device links to them, but nothing detaches them when
imx_pcie_probe() subsequently fails or defers.  This leaks the power
domains and device links on every probe failure or deferral.

Save the device links and add imx_pcie_detach_pd() to release them,
calling it from the probe error paths.

Reported-by: [email protected]
Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: hanzhijian <[email protected]>
---
 drivers/pci/controller/dwc/pci-imx6.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index 39790e66b..4df548679 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -182,6 +182,9 @@ struct imx_pcie {
 	struct device		*pd_pcie;
 	/* power domain for pcie phy */
 	struct device		*pd_pcie_phy;
+	/* device links for the power domains */
+	struct device_link	*pd_link;
+	struct device_link	*pd_phy_link;
 	struct phy		*phy;
 	const struct imx_pcie_drvdata *drvdata;
 
@@ -662,6 +665,7 @@ static int imx_pcie_attach_pd(struct device *dev)
 		dev_err(dev, "Failed to add device_link to pcie pd\n");
 		return -EINVAL;
 	}
+	imx_pcie->pd_link = link;
 
 	imx_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
 	if (IS_ERR(imx_pcie->pd_pcie_phy))
@@ -675,10 +679,24 @@ static int imx_pcie_attach_pd(struct device *dev)
 		dev_err(dev, "Failed to add device_link to pcie_phy pd\n");
 		return -EINVAL;
 	}
+	imx_pcie->pd_phy_link = link;
 
 	return 0;
 }
 
+static void imx_pcie_detach_pd(struct imx_pcie *imx_pcie)
+{
+	if (imx_pcie->pd_link)
+		device_link_del(imx_pcie->pd_link);
+	if (imx_pcie->pd_pcie)
+		dev_pm_domain_detach(imx_pcie->pd_pcie, true);
+
+	if (imx_pcie->pd_phy_link)
+		device_link_del(imx_pcie->pd_phy_link);
+	if (imx_pcie->pd_pcie_phy)
+		dev_pm_domain_detach(imx_pcie->pd_pcie_phy, true);
+}
+
 static int imx6q_pcie_enable_ref_clk(struct imx_pcie *imx_pcie, bool enable)
 {
 	if (enable)
@@ -1956,8 +1974,10 @@ static int imx_pcie_probe(struct platform_device *pdev)
 		return ret;
 
 	ret = pci_pwrctrl_create_devices(dev);
-	if (ret)
+	if (ret) {
+		imx_pcie_detach_pd(imx_pcie);
 		return dev_err_probe(dev, ret, "failed to create pwrctrl devices\n");
+	}
 
 	pci->use_parent_dt_ranges = true;
 	if (imx_pcie->drvdata->mode == DW_PCIE_EP_TYPE) {
@@ -1999,6 +2019,7 @@ static int imx_pcie_probe(struct platform_device *pdev)
 	return 0;
 
 err_pwrctrl_destroy:
+	imx_pcie_detach_pd(imx_pcie);
 	if (ret != -EPROBE_DEFER)
 		pci_pwrctrl_destroy_devices(dev);
 	return ret;
-- 
2.43.0