PCI: dwc: Fix type mismatch for kstrtou32_from_user() return value

[ Upstream commit 445588a ]

kstrtou32_from_user() returns int, but the return value was stored in
a u32 variable 'val', risking sign loss. Use a dedicated int variable
to correctly handle the return code.

Fixes: 4fbfa17 ("PCI: dwc: Add debugfs based Silicon Debug support for DWC")
Signed-off-by: Hans Zhang <18255117159@163.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20260401023048.4182452-1-18255117159@163.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: Hans Zhang

drivers/pci/controller/dwc/pcie-designware-debugfs.c

@@ -208,10 +208,11 @@ static ssize_t lane_detect_write(struct file *file, const char __user *buf,
 	struct dw_pcie *pci = file->private_data;
 	struct dwc_pcie_rasdes_info *rinfo = pci->debugfs->rasdes_info;
 	u32 lane, val;
+	int ret;
 
-	val = kstrtou32_from_user(buf, count, 0, &lane);
-	if (val)
-		return val;
+	ret = kstrtou32_from_user(buf, count, 0, &lane);
+	if (ret)
+		return ret;
 
 	val = dw_pcie_readl_dbi(pci, rinfo->ras_cap_offset + SD_STATUS_L1LANE_REG);
 	val &= ~(LANE_SELECT);
@@ -347,10 +348,11 @@ static ssize_t counter_enable_write(struct file *file, const char __user *buf,
 	struct dw_pcie *pci = pdata->pci;
 	struct dwc_pcie_rasdes_info *rinfo = pci->debugfs->rasdes_info;
 	u32 val, enable;
+	int ret;
 
-	val = kstrtou32_from_user(buf, count, 0, &enable);
-	if (val)
-		return val;
+	ret = kstrtou32_from_user(buf, count, 0, &enable);
+	if (ret)
+		return ret;
 
 	mutex_lock(&rinfo->reg_event_lock);
 	set_event_number(pdata, pci, rinfo);
@@ -408,10 +410,11 @@ static ssize_t counter_lane_write(struct file *file, const char __user *buf,
 	struct dw_pcie *pci = pdata->pci;
 	struct dwc_pcie_rasdes_info *rinfo = pci->debugfs->rasdes_info;
 	u32 val, lane;
+	int ret;
 
-	val = kstrtou32_from_user(buf, count, 0, &lane);
-	if (val)
-		return val;
+	ret = kstrtou32_from_user(buf, count, 0, &lane);
+	if (ret)
+		return ret;
 
 	mutex_lock(&rinfo->reg_event_lock);
 	set_event_number(pdata, pci, rinfo);