net: macb: free resources on failure path of at91ether_open()

DMA buffers were not freed on failure path of at91ether_open().
Along with changes for freeing the DMA buffers the enable/disable
interrupt instructions were moved to at91ether_start()/at91ether_stop()
functions and the operations on at91ether_stop() were done in
their reverse order (compared with how is done in at91ether_start()):
before this patch the operation order on interface open path
was as follows:
1/ alloc DMA buffers
2/ enable tx, rx
3/ enable interrupts
and the order on interface close path was as follows:
1/ disable tx, rx
2/ disable interrupts
3/ free dma buffers.

Fixes: 7897b071ac3b ("net: macb: convert to phylink")
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 5705359..52582e8 100644 (file)
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -3762,15 +3762,9 @@ static int macb_init(struct platform_device *pdev)
 
 static struct sifive_fu540_macb_mgmt *mgmt;
 
-/* Initialize and start the Receiver and Transmit subsystems */
-static int at91ether_start(struct net_device *dev)
+static int at91ether_alloc_coherent(struct macb *lp)
 {
-       struct macb *lp = netdev_priv(dev);
        struct macb_queue *q = &lp->queues[0];
-       struct macb_dma_desc *desc;
-       dma_addr_t addr;
-       u32 ctl;
-       int i;
 
        q->rx_ring = dma_alloc_coherent(&lp->pdev->dev,
                                         (AT91ETHER_MAX_RX_DESCR *
@@ -3792,6 +3786,43 @@ static int at91ether_start(struct net_device *dev)
                return -ENOMEM;
        }
 
+       return 0;
+}
+
+static void at91ether_free_coherent(struct macb *lp)
+{
+       struct macb_queue *q = &lp->queues[0];
+
+       if (q->rx_ring) {
+               dma_free_coherent(&lp->pdev->dev,
+                                 AT91ETHER_MAX_RX_DESCR *
+                                 macb_dma_desc_get_size(lp),
+                                 q->rx_ring, q->rx_ring_dma);
+               q->rx_ring = NULL;
+       }
+
+       if (q->rx_buffers) {
+               dma_free_coherent(&lp->pdev->dev,
+                                 AT91ETHER_MAX_RX_DESCR *
+                                 AT91ETHER_MAX_RBUFF_SZ,
+                                 q->rx_buffers, q->rx_buffers_dma);
+               q->rx_buffers = NULL;
+       }
+}
+
+/* Initialize and start the Receiver and Transmit subsystems */
+static int at91ether_start(struct macb *lp)
+{
+       struct macb_queue *q = &lp->queues[0];
+       struct macb_dma_desc *desc;
+       dma_addr_t addr;
+       u32 ctl;
+       int i, ret;
+
+       ret = at91ether_alloc_coherent(lp);
+       if (ret)
+               return ret;
+
        addr = q->rx_buffers_dma;
        for (i = 0; i < AT91ETHER_MAX_RX_DESCR; i++) {
                desc = macb_rx_desc(q, i);
@@ -3813,9 +3844,39 @@ static int at91ether_start(struct net_device *dev)
        ctl = macb_readl(lp, NCR);
        macb_writel(lp, NCR, ctl | MACB_BIT(RE) | MACB_BIT(TE));
 
+       /* Enable MAC interrupts */
+       macb_writel(lp, IER, MACB_BIT(RCOMP)    |
+                            MACB_BIT(RXUBR)    |
+                            MACB_BIT(ISR_TUND) |
+                            MACB_BIT(ISR_RLE)  |
+                            MACB_BIT(TCOMP)    |
+                            MACB_BIT(ISR_ROVR) |
+                            MACB_BIT(HRESP));
+
        return 0;
 }
 
+static void at91ether_stop(struct macb *lp)
+{
+       u32 ctl;
+
+       /* Disable MAC interrupts */
+       macb_writel(lp, IDR, MACB_BIT(RCOMP)    |
+                            MACB_BIT(RXUBR)    |
+                            MACB_BIT(ISR_TUND) |
+                            MACB_BIT(ISR_RLE)  |
+                            MACB_BIT(TCOMP)    |
+                            MACB_BIT(ISR_ROVR) |
+                            MACB_BIT(HRESP));
+
+       /* Disable Receiver and Transmitter */
+       ctl = macb_readl(lp, NCR);
+       macb_writel(lp, NCR, ctl & ~(MACB_BIT(TE) | MACB_BIT(RE)));
+
+       /* Free resources. */
+       at91ether_free_coherent(lp);
+}
+
 /* Open the ethernet interface */
 static int at91ether_open(struct net_device *dev)
 {
@@ -3835,27 +3896,20 @@ static int at91ether_open(struct net_device *dev)
 
        macb_set_hwaddr(lp);
 
-       ret = at91ether_start(dev);
+       ret = at91ether_start(lp);
        if (ret)
                goto pm_exit;
 
-       /* Enable MAC interrupts */
-       macb_writel(lp, IER, MACB_BIT(RCOMP)    |
-                            MACB_BIT(RXUBR)    |
-                            MACB_BIT(ISR_TUND) |
-                            MACB_BIT(ISR_RLE)  |
-                            MACB_BIT(TCOMP)    |
-                            MACB_BIT(ISR_ROVR) |
-                            MACB_BIT(HRESP));
-
        ret = macb_phylink_connect(lp);
        if (ret)
-               goto pm_exit;
+               goto stop;
 
        netif_start_queue(dev);
 
        return 0;
 
+stop:
+       at91ether_stop(lp);
 pm_exit:
        pm_runtime_put_sync(&lp->pdev->dev);
        return ret;
@@ -3865,37 +3919,13 @@ pm_exit:
 static int at91ether_close(struct net_device *dev)
 {
        struct macb *lp = netdev_priv(dev);
-       struct macb_queue *q = &lp->queues[0];
-       u32 ctl;
-
-       /* Disable Receiver and Transmitter */
-       ctl = macb_readl(lp, NCR);
-       macb_writel(lp, NCR, ctl & ~(MACB_BIT(TE) | MACB_BIT(RE)));
-
-       /* Disable MAC interrupts */
-       macb_writel(lp, IDR, MACB_BIT(RCOMP)    |
-                            MACB_BIT(RXUBR)    |
-                            MACB_BIT(ISR_TUND) |
-                            MACB_BIT(ISR_RLE)  |
-                            MACB_BIT(TCOMP)    |
-                            MACB_BIT(ISR_ROVR) |
-                            MACB_BIT(HRESP));
 
        netif_stop_queue(dev);
 
        phylink_stop(lp->phylink);
        phylink_disconnect_phy(lp->phylink);
 
-       dma_free_coherent(&lp->pdev->dev,
-                         AT91ETHER_MAX_RX_DESCR *
-                         macb_dma_desc_get_size(lp),
-                         q->rx_ring, q->rx_ring_dma);
-       q->rx_ring = NULL;
-
-       dma_free_coherent(&lp->pdev->dev,
-                         AT91ETHER_MAX_RX_DESCR * AT91ETHER_MAX_RBUFF_SZ,
-                         q->rx_buffers, q->rx_buffers_dma);
-       q->rx_buffers = NULL;
+       at91ether_stop(lp);
 
        return pm_runtime_put(&lp->pdev->dev);
 }