[PATCH v2 2/3] PCI: mediatek-gen3: Do not break probe flow when MSI init fails

From: Jianjun Wang
Date: Mon Dec 11 2023 - 03:53:23 EST


Since INTx can still work, the driver probe flow should not be broken by
MSI initialization failures. Additionally, moving the MSI initialization
code into a single function enhances readability.

Fixes: 1bdafba538be ("PCI: mediatek-gen3: Add MSI support")
Signed-off-by: Jianjun Wang <jianjun.wang@xxxxxxxxxxxx>
---
drivers/pci/controller/pcie-mediatek-gen3.c | 68 ++++++++++-----------
1 file changed, 33 insertions(+), 35 deletions(-)

diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
index c1ae3d19ec9a..c6a6876d233a 100644
--- a/drivers/pci/controller/pcie-mediatek-gen3.c
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -649,59 +649,51 @@ static const struct irq_domain_ops intx_domain_ops = {
.map = mtk_pcie_intx_map,
};

-static int mtk_pcie_init_irq_domains(struct mtk_gen3_pcie *pcie)
+static int mtk_pcie_init_msi(struct mtk_gen3_pcie *pcie)
{
struct device *dev = pcie->dev;
- struct device_node *intc_node, *node = dev->of_node;
- int ret;
-
- raw_spin_lock_init(&pcie->irq_lock);
-
- /* Setup INTx */
- intc_node = of_get_child_by_name(node, "interrupt-controller");
- if (!intc_node) {
- dev_err(dev, "missing interrupt-controller node\n");
- return -ENODEV;
- }
-
- pcie->intx_domain = irq_domain_add_linear(intc_node, PCI_NUM_INTX,
- &intx_domain_ops, pcie);
- if (!pcie->intx_domain) {
- dev_err(dev, "failed to create INTx IRQ domain\n");
- ret = -ENODEV;
- goto out_put_node;
- }
+ struct device_node *node = dev->of_node;

- /* Setup MSI */
mutex_init(&pcie->lock);

pcie->msi_bottom_domain = irq_domain_add_linear(node, PCIE_MSI_IRQS_NUM,
&mtk_msi_bottom_domain_ops, pcie);
if (!pcie->msi_bottom_domain) {
dev_err(dev, "failed to create MSI bottom domain\n");
- ret = -ENODEV;
- goto err_msi_bottom_domain;
+ return -ENODEV;
}

- pcie->msi_domain = pci_msi_create_irq_domain(dev->fwnode,
- &mtk_msi_domain_info,
+ pcie->msi_domain = pci_msi_create_irq_domain(dev->fwnode, &mtk_msi_domain_info,
pcie->msi_bottom_domain);
if (!pcie->msi_domain) {
dev_err(dev, "failed to create MSI domain\n");
- ret = -ENODEV;
- goto err_msi_domain;
+ irq_domain_remove(pcie->msi_bottom_domain);
+ return -ENODEV;
}

- of_node_put(intc_node);
return 0;
+}

-err_msi_domain:
- irq_domain_remove(pcie->msi_bottom_domain);
-err_msi_bottom_domain:
- irq_domain_remove(pcie->intx_domain);
-out_put_node:
+static int mtk_pcie_init_intx(struct mtk_gen3_pcie *pcie)
+{
+ struct device *dev = pcie->dev;
+ struct device_node *intc_node, *node = dev->of_node;
+
+ intc_node = of_get_child_by_name(node, "interrupt-controller");
+ if (!intc_node) {
+ dev_err(dev, "missing interrupt-controller node\n");
+ return -ENODEV;
+ }
+
+ pcie->intx_domain = irq_domain_add_linear(intc_node, PCI_NUM_INTX,
+ &intx_domain_ops, pcie);
of_node_put(intc_node);
- return ret;
+ if (!pcie->intx_domain) {
+ dev_err(dev, "failed to create INTx IRQ domain\n");
+ return -ENODEV;
+ }
+
+ return 0;
}

static void mtk_pcie_irq_teardown(struct mtk_gen3_pcie *pcie)
@@ -774,10 +766,16 @@ static int mtk_pcie_setup_irq(struct mtk_gen3_pcie *pcie)
struct platform_device *pdev = to_platform_device(dev);
int err;

- err = mtk_pcie_init_irq_domains(pcie);
+ raw_spin_lock_init(&pcie->irq_lock);
+
+ err = mtk_pcie_init_intx(pcie);
if (err)
return err;

+ err = mtk_pcie_init_msi(pcie);
+ if (err)
+ dev_warn(dev, "no MSI supported, only INTx available\n");
+
pcie->irq = platform_get_irq(pdev, 0);
if (pcie->irq < 0)
return pcie->irq;
--
2.18.0