[PATCH v4 10/10] PCI: Reduce redundancy in current_link_speed_show()

[Yicong Yang <yangyicong@xxxxxxxxxxxxx>]

Remove switch-case statements in current_link_speed_show(). Use
pcie_link_speed[] array to get link speed and PCI_SPEED2STR macro
to get link speed string.

Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
---
 drivers/pci/pci-sysfs.c | 24 +++---------------------
 1 file changed, 3 insertions(+), 21 deletions(-)

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index f4eafbc..eaece10 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -175,33 +175,15 @@ static ssize_t current_link_speed_show(struct device *dev,
 	struct pci_dev *pci_dev = to_pci_dev(dev);
 	u16 linkstat;
 	int err;
-	const char *speed;
+	enum pci_bus_speed speed;
 
 	err = pcie_capability_read_word(pci_dev, PCI_EXP_LNKSTA, &linkstat);
 	if (err)
 		return -EINVAL;
 
-	switch (linkstat & PCI_EXP_LNKSTA_CLS) {
-	case PCI_EXP_LNKSTA_CLS_32_0GB:
-		speed = "32 GT/s";
-		break;
-	case PCI_EXP_LNKSTA_CLS_16_0GB:
-		speed = "16 GT/s";
-		break;
-	case PCI_EXP_LNKSTA_CLS_8_0GB:
-		speed = "8 GT/s";
-		break;
-	case PCI_EXP_LNKSTA_CLS_5_0GB:
-		speed = "5 GT/s";
-		break;
-	case PCI_EXP_LNKSTA_CLS_2_5GB:
-		speed = "2.5 GT/s";
-		break;
-	default:
-		speed = "Unknown speed";
-	}
+	speed = pcie_link_speed[linkstat & PCI_EXP_LNKSTA_CLS];
 
-	return sprintf(buf, "%s\n", speed);
+	return sprintf(buf, "%s\n", PCI_SPEED2STR(speed));
 }
 static DEVICE_ATTR_RO(current_link_speed);
 
-- 
2.8.1