crypto: hisilicon/qm - add pci bdf number check

The pci bdf number check is added for qos written by using the pci api.
Directly get the devfn by pci_dev, so delete some redundant code.
And use the kstrtoul instead of sscanf to simplify code.
Signed-off-by: Kai Ye <yekai13@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/hisilicon/qm.c

@@ -4589,49 +4589,36 @@ static ssize_t qm_algqos_read(struct file *filp, char __user *buf,
 	return ret;
 }
 
-static ssize_t qm_qos_value_init(const char *buf, unsigned long *val)
-{
-	int buflen = strlen(buf);
-	int ret, i;
-
-	for (i = 0; i < buflen; i++) {
-		if (!isdigit(buf[i]))
-			return -EINVAL;
-	}
-
-	ret = sscanf(buf, "%lu", val);
-	if (ret != QM_QOS_VAL_NUM)
-		return -EINVAL;
-
-	return 0;
-}
-
 static ssize_t qm_get_qos_value(struct hisi_qm *qm, const char *buf,
 			       unsigned long *val,
 			       unsigned int *fun_index)
 {
+	struct bus_type *bus_type = qm->pdev->dev.bus;
 	char tbuf_bdf[QM_DBG_READ_LEN] = {0};
 	char val_buf[QM_DBG_READ_LEN] = {0};
-	u32 tmp1, device, function;
-	int ret, bus;
+	struct pci_dev *pdev;
+	struct device *dev;
+	int ret;
 
 	ret = sscanf(buf, "%s %s", tbuf_bdf, val_buf);
 	if (ret != QM_QOS_PARAM_NUM)
 		return -EINVAL;
 
-	ret = qm_qos_value_init(val_buf, val);
+	ret = kstrtoul(val_buf, 10, val);
 	if (ret || *val == 0 || *val > QM_QOS_MAX_VAL) {
 		pci_err(qm->pdev, "input qos value is error, please set 1~1000!\n");
 		return -EINVAL;
 	}
 
-	ret = sscanf(tbuf_bdf, "%u:%x:%u.%u", &tmp1, &bus, &device, &function);
-	if (ret != QM_QOS_BDF_PARAM_NUM) {
-		pci_err(qm->pdev, "input pci bdf value is error!\n");
-		return -EINVAL;
+	dev = bus_find_device_by_name(bus_type, NULL, tbuf_bdf);
+	if (!dev) {
+		pci_err(qm->pdev, "input pci bdf number is error!\n");
+		return -ENODEV;
 	}
 
-	*fun_index = PCI_DEVFN(device, function);
+	pdev = container_of(dev, struct pci_dev, dev);
+
+	*fun_index = pdev->devfn;
 
 	return 0;
 }