[PATCH v2 1/1] fpga: altera-cvp: Use pci_find_vsec_capability() when probing FPGA device

From: Andy Shevchenko
Date: Fri Jun 27 2025 - 07:27:55 EST


Currently altera_cvp_probe() open-codes pci_find_vsec_capability().
Refactor the former to use the latter. No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---

v2: removed unused variable (LKP)

drivers/fpga/altera-cvp.c | 20 +++++---------------
1 file changed, 5 insertions(+), 15 deletions(-)

diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c
index 5af0bd33890c..514d2ac18e5f 100644
--- a/drivers/fpga/altera-cvp.c
+++ b/drivers/fpga/altera-cvp.c
@@ -22,9 +22,6 @@
#define TIMEOUT_US 2000 /* CVP STATUS timeout for USERMODE polling */

/* Vendor Specific Extended Capability Registers */
-#define VSE_PCIE_EXT_CAP_ID 0x0
-#define VSE_PCIE_EXT_CAP_ID_VAL 0x000b /* 16bit */
-
#define VSE_CVP_STATUS 0x1c /* 32bit */
#define VSE_CVP_STATUS_CFG_RDY BIT(18) /* CVP_CONFIG_READY */
#define VSE_CVP_STATUS_CFG_ERR BIT(19) /* CVP_CONFIG_ERROR */
@@ -577,25 +574,18 @@ static int altera_cvp_probe(struct pci_dev *pdev,
{
struct altera_cvp_conf *conf;
struct fpga_manager *mgr;
- int ret, offset;
- u16 cmd, val;
+ u16 cmd, offset;
u32 regval;
-
- /* Discover the Vendor Specific Offset for this device */
- offset = pci_find_next_ext_capability(pdev, 0, PCI_EXT_CAP_ID_VNDR);
- if (!offset) {
- dev_err(&pdev->dev, "No Vendor Specific Offset.\n");
- return -ENODEV;
- }
+ int ret;

/*
* First check if this is the expected FPGA device. PCI config
* space access works without enabling the PCI device, memory
* space access is enabled further down.
*/
- pci_read_config_word(pdev, offset + VSE_PCIE_EXT_CAP_ID, &val);
- if (val != VSE_PCIE_EXT_CAP_ID_VAL) {
- dev_err(&pdev->dev, "Wrong EXT_CAP_ID value 0x%x\n", val);
+ offset = pci_find_vsec_capability(pdev, PCI_VENDOR_ID_ALTERA, 0);
+ if (!offset) {
+ dev_err(&pdev->dev, "Wrong EXT_CAP_ID value\n");
return -ENODEV;
}

--
2.47.2