r8169: improve interrupt handling

This patch improves few aspects of interrupt handling:
- update to current interrupt allocation API
  (use pci_alloc_irq_vectors() instead of deprecated pci_enable_msi())
- this implicitly will allocate a MSI-X interrupt if available
- get rid of flag RTL_FEATURE_MSI
- remove some dead code, intentionally disabling (unreliable) MSI
  being partially available on old PCI chips.

The patch works fine on a RTL8168evl (chip version 34) and on a
RTL8169SB (chip version 04).

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 21 insertions, 27 deletions

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index 96db3283eecf..cc51286ee51f 100644
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -736,8 +736,7 @@ struct ring_info {
 };
 
 enum features {
-        RTL_FEATURE_MSI         = (1 << 0),
-        RTL_FEATURE_GMII        = (1 << 1),
+        RTL_FEATURE_GMII        = (1 << 0),
 };
 
 struct rtl8169_counters {
@@ -7847,7 +7846,7 @@ static int rtl8169_close(struct net_device *dev)
 
         cancel_work_sync(&tp->wk.work);
 
-        free_irq(pdev->irq, dev);
+        pci_free_irq(pdev, 0, dev);
 
         dma_free_coherent(&pdev->dev, R8169_RX_RING_BYTES, tp->RxDescArray,
                           tp->RxPhyAddr);
@@ -7903,9 +7902,8 @@ static int rtl_open(struct net_device *dev)
 
         rtl_request_firmware(tp);
 
-        retval = request_irq(pdev->irq, rtl8169_interrupt,
-                             (tp->features & RTL_FEATURE_MSI) ? 0 : IRQF_SHARED,
-                             dev->name, dev);
+        retval = pci_request_irq(pdev, 0, rtl8169_interrupt, NULL, dev,
+                                 dev->name);
         if (retval < 0)
                 goto err_release_fw_2;
 
@@ -8253,7 +8251,7 @@ static const struct rtl_cfg_info {
                 .region         = 2,
                 .align          = 8,
                 .event_slow     = SYSErr | LinkChg | RxOverflow,
-                .features       = RTL_FEATURE_GMII | RTL_FEATURE_MSI,
+                .features       = RTL_FEATURE_GMII,
                 .coalesce_info  = rtl_coalesce_info_8168_8136,
                 .default_ver    = RTL_GIGA_MAC_VER_11,
         },
@@ -8263,32 +8261,26 @@ static const struct rtl_cfg_info {
                 .align          = 8,
                 .event_slow     = SYSErr | LinkChg | RxOverflow | RxFIFOOver |
                                   PCSTimeout,
-                .features       = RTL_FEATURE_MSI,
                 .coalesce_info  = rtl_coalesce_info_8168_8136,
                 .default_ver    = RTL_GIGA_MAC_VER_13,
         }
 };
 
-/* Cfg9346_Unlock assumed. */
-static unsigned rtl_try_msi(struct rtl8169_private *tp,
-                            const struct rtl_cfg_info *cfg)
+static int rtl_alloc_irq(struct rtl8169_private *tp)
 {
         void __iomem *ioaddr = tp->mmio_addr;
-        unsigned msi = 0;
-        u8 cfg2;
+        unsigned int flags;
 
-        cfg2 = RTL_R8(Config2) & ~MSIEnable;
-        if (cfg->features & RTL_FEATURE_MSI) {
-                if (pci_enable_msi(tp->pci_dev)) {
-                        netif_info(tp, hw, tp->dev, "no MSI. Back to INTx.\n");
-                } else {
-                        cfg2 |= MSIEnable;
-                        msi = RTL_FEATURE_MSI;
-                }
+        if (tp->mac_version <= RTL_GIGA_MAC_VER_06) {
+                RTL_W8(Cfg9346, Cfg9346_Unlock);
+                RTL_W8(Config2, RTL_R8(Config2) & ~MSIEnable);
+                RTL_W8(Cfg9346, Cfg9346_Lock);
+                flags = PCI_IRQ_LEGACY;
+        } else {
+                flags = PCI_IRQ_ALL_TYPES;
         }
-        if (tp->mac_version <= RTL_GIGA_MAC_VER_06)
-                RTL_W8(Config2, cfg2);
-        return msi;
+
+        return pci_alloc_irq_vectors(tp->pci_dev, 1, 1, flags);
 }
 
 DECLARE_RTL_COND(rtl_link_list_ready_cond)
@@ -8497,9 +8489,11 @@ static int rtl_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
         chipset = tp->mac_version;
         tp->txd_version = rtl_chip_infos[chipset].txd_version;
 
-        RTL_W8(Cfg9346, Cfg9346_Unlock);
-        tp->features |= rtl_try_msi(tp, cfg);
-        RTL_W8(Cfg9346, Cfg9346_Lock);
+        rc = rtl_alloc_irq(tp);
+        if (rc < 0) {
+                netif_err(tp, probe, dev, "Can't allocate interrupt\n");
+                return rc;
+        }
 
         /* override BIOS settings, use userspace tools to enable WOL */
         __rtl8169_set_wol(tp, 0);