net: macb: ensure interface is not suspended on at91rm9200

[ Upstream commit e042252bef86b2be3bfc6b2bde92809d6be7cd3f ]

Because of autosuspend, at91ether_start is called with clocks disabled.
Ensure that pm_runtime doesn't suspend the interface as soon as it is
opened as there is no pm_runtime support is the other relevant parts of the
platform support for at91rm9200.

Fixes: 03c922bc9154 ("net: macb: Add pm runtime support")
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 95a94507cec1222e2a5e5dabb3e927e79d55d749..234c13ebbc41b69c990b8876fa5b3f433caba0ef 100644 (file)
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -3690,6 +3690,10 @@ static int at91ether_open(struct net_device *dev)
        u32 ctl;
        int ret;
 
+       ret = pm_runtime_get_sync(&lp->pdev->dev);
+       if (ret < 0)
+               return ret;
+
        /* Clear internal statistics */
        ctl = macb_readl(lp, NCR);
        macb_writel(lp, NCR, ctl | MACB_BIT(CLRSTAT));
@@ -3750,7 +3754,7 @@ static int at91ether_close(struct net_device *dev)
                          q->rx_buffers, q->rx_buffers_dma);
        q->rx_buffers = NULL;
 
-       return 0;
+       return pm_runtime_put(&lp->pdev->dev);
 }
 
 /* Transmit packet */