[PATCH] PCI: iproc: fix -Wvoid-pointer-to-enum-cast warning

From: Justin Stitt
Date: Mon Aug 14 2023 - 18:30:05 EST


When building with clang 18 I see the following warning:
| drivers/pci/controller/pcie-iproc-platform.c:55:15: warning: cast to smaller
| integer type 'enum iproc_pcie_type' from 'const void *' [-Wvoid-pointer-to-enum-cast]
| 55 | pcie->type = (enum iproc_pcie_type) of_device_get_match_data(dev);

This is due to the fact that `of_device_get_match_data` returns a void*
while `enum iproc_pcie_type` has the size of an int. This leads to
truncation and possible data loss.

Link: https://github.com/ClangBuiltLinux/linux/issues/1910
Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx>
---
Note: There is likely no data loss occurring here since `enum
iproc_pcie_type` has only a few fields enumerated from 0. Definitely not
enough to cause data loss from pointer-width to int-width.
---
drivers/pci/controller/pcie-iproc-platform.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/pcie-iproc-platform.c b/drivers/pci/controller/pcie-iproc-platform.c
index acdc583d2980..83cbc95f4384 100644
--- a/drivers/pci/controller/pcie-iproc-platform.c
+++ b/drivers/pci/controller/pcie-iproc-platform.c
@@ -52,7 +52,7 @@ static int iproc_pltfm_pcie_probe(struct platform_device *pdev)
pcie = pci_host_bridge_priv(bridge);

pcie->dev = dev;
- pcie->type = (enum iproc_pcie_type) of_device_get_match_data(dev);
+ pcie->type = (uintptr_t) of_device_get_match_data(dev);

ret = of_address_to_resource(np, 0, &reg);
if (ret < 0) {

---
base-commit: 2ccdd1b13c591d306f0401d98dedc4bdcd02b421
change-id: 20230814-void-drivers-pci-controller-pcie-iproc-platform-ada4ac9a9a75

Best regards,
--
Justin Stitt <justinstitt@xxxxxxxxxx>