sfc: Replace MDIO spinlock with mutex

We never use MDIO in atomic context, so we don't need to spin.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/sfc/efx.c

@@ -1922,7 +1922,7 @@ static int efx_init_struct(struct efx_nic *efx, struct efx_nic_type *type,
 	/* Initialise common structures */
 	memset(efx, 0, sizeof(*efx));
 	spin_lock_init(&efx->biu_lock);
-	spin_lock_init(&efx->phy_lock);
+	mutex_init(&efx->mdio_lock);
 	mutex_init(&efx->spi_lock);
 	INIT_WORK(&efx->reset_work, efx_reset_work);
 	INIT_DELAYED_WORK(&efx->monitor_work, efx_monitor);

drivers/net/sfc/falcon.c

@@ -2110,7 +2110,7 @@ static int falcon_mdio_write(struct net_device *net_dev,
 	EFX_REGDUMP(efx, "writing MDIO %d register %d.%d with 0x%04x\n",
 		    prtad, devad, addr, value);
 
-	spin_lock_bh(&efx->phy_lock);
+	mutex_lock(&efx->mdio_lock);
 
 	/* Check MDIO not currently being accessed */
 	rc = falcon_gmii_wait(efx);
@@ -2145,8 +2145,8 @@ static int falcon_mdio_write(struct net_device *net_dev,
 		udelay(10);
 	}
 
- out:
-	spin_unlock_bh(&efx->phy_lock);
+out:
+	mutex_unlock(&efx->mdio_lock);
 	return rc;
 }
 
@@ -2158,7 +2158,7 @@ static int falcon_mdio_read(struct net_device *net_dev,
 	efx_oword_t reg;
 	int rc;
 
-	spin_lock_bh(&efx->phy_lock);
+	mutex_lock(&efx->mdio_lock);
 
 	/* Check MDIO not currently being accessed */
 	rc = falcon_gmii_wait(efx);
@@ -2194,8 +2194,8 @@ static int falcon_mdio_read(struct net_device *net_dev,
 			prtad, devad, addr, rc);
 	}
 
- out:
-	spin_unlock_bh(&efx->phy_lock);
+out:
+	mutex_unlock(&efx->mdio_lock);
 	return rc;
 }
 

drivers/net/sfc/net_driver.h

@@ -724,7 +724,7 @@ union efx_multicast_hash {
  * @mac_op: MAC interface
  * @mac_address: Permanent MAC address
  * @phy_type: PHY type
- * @phy_lock: PHY access lock
+ * @mdio_lock: MDIO lock
  * @phy_op: PHY interface
  * @phy_data: PHY private data (including PHY-specific stats)
  * @mdio: PHY MDIO interface
@@ -806,7 +806,7 @@ struct efx_nic {
 	unsigned char mac_address[ETH_ALEN];
 
 	enum phy_type phy_type;
-	spinlock_t phy_lock;
+	struct mutex mdio_lock;
 	struct efx_phy_operations *phy_op;
 	void *phy_data;
 	struct mdio_if_info mdio;