DM9000: Wake on LAN support

Add support for Wake on LAN (WOL) reception and waking the device up from
this signal via the ethtool interface. Currently we are only supporting
the magic-packet variant of wakeup.

WOL is enabled by specifying a second interrupt resource to the driver
which indicates where the interrupt for the WOL is being signalled. This
then enables the necessary ethtool calls to leave the device in a state
to receive WOL frames when going into suspend.

Signed-off-by: Ben Dooks <[e-mail]>
Signed-off-by: Simtec Linux Team <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/dm9000.c

···
 
 	unsigned int	flags;
 	unsigned int	in_suspend :1;
+	unsigned int	wake_supported :1;
 	int		debug_level;
 
 	enum dm9000_type type;
···
 	struct resource *data_req;
 	struct resource *irq_res;
 
+	int		 irq_wake;
+
 	struct mutex	 addr_lock;	/* phy and eeprom access lock */
 
 	struct delayed_work phy_poll;
···
 
 	struct mii_if_info mii;
 	u32		msg_enable;
+	u32		wake_state;
 
 	int		rx_csum;
 	int		can_csum;
···
 	return 0;
 }
 
+static void dm9000_get_wol(struct net_device *dev, struct ethtool_wolinfo *w)
+{
+	board_info_t *dm = to_dm9000_board(dev);
+
+	memset(w, 0, sizeof(struct ethtool_wolinfo));
+
+	/* note, we could probably support wake-phy too */
+	w->supported = dm->wake_supported ? WAKE_MAGIC : 0;
+	w->wolopts = dm->wake_state;
+}
+
+static int dm9000_set_wol(struct net_device *dev, struct ethtool_wolinfo *w)
+{
+	board_info_t *dm = to_dm9000_board(dev);
+	unsigned long flags;
+	u32 opts = w->wolopts;
+	u32 wcr = 0;
+
+	if (!dm->wake_supported)
+		return -EOPNOTSUPP;
+
+	if (opts & ~WAKE_MAGIC)
+		return -EINVAL;
+
+	if (opts & WAKE_MAGIC)
+		wcr |= WCR_MAGICEN;
+
+	mutex_lock(&dm->addr_lock);
+
+	spin_lock_irqsave(&dm->lock, flags);
+	iow(dm, DM9000_WCR, wcr);
+	spin_unlock_irqrestore(&dm->lock, flags);
+
+	mutex_unlock(&dm->addr_lock);
+
+	if (dm->wake_state != opts) {
+		/* change in wol state, update IRQ state */
+
+		if (!dm->wake_state)
+			set_irq_wake(dm->irq_wake, 1);
+		else if (dm->wake_state & !opts)
+			set_irq_wake(dm->irq_wake, 0);
+	}
+
+	dm->wake_state = opts;
+	return 0;
+}
+
 static const struct ethtool_ops dm9000_ethtool_ops = {
 	.get_drvinfo		= dm9000_get_drvinfo,
 	.get_settings		= dm9000_get_settings,
···
 	.set_msglevel		= dm9000_set_msglevel,
 	.nway_reset		= dm9000_nway_reset,
 	.get_link		= dm9000_get_link,
+	.get_wol		= dm9000_get_wol,
+	.set_wol		= dm9000_set_wol,
  	.get_eeprom_len		= dm9000_get_eeprom_len,
  	.get_eeprom		= dm9000_get_eeprom,
  	.set_eeprom		= dm9000_set_eeprom,
···
 {
 	board_info_t *db = netdev_priv(dev);
 	unsigned int imr;
+	unsigned int ncr;
 
 	dm9000_dbg(db, 1, "entering %s\n", __func__);
 
···
 	iow(db, DM9000_GPCR, GPCR_GEP_CNTL);	/* Let GPIO0 output */
 	iow(db, DM9000_GPR, 0);	/* Enable PHY */
 
-	if (db->flags & DM9000_PLATF_EXT_PHY)
-		iow(db, DM9000_NCR, NCR_EXT_PHY);
+	ncr = (db->flags & DM9000_PLATF_EXT_PHY) ? NCR_EXT_PHY : 0;
+
+	/* if wol is needed, then always set NCR_WAKEEN otherwise we end
+	 * up dumping the wake events if we disable this. There is already
+	 * a wake-mask in DM9000_WCR */
+	if (db->wake_supported)
+		ncr |= NCR_WAKEEN;
+
+	iow(db, DM9000_NCR, ncr);
 
 	/* Program operating register */
 	iow(db, DM9000_TCR, 0);	        /* TX Polling clear */
···
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t dm9000_wol_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = dev_id;
+	board_info_t *db = netdev_priv(dev);
+	unsigned long flags;
+	unsigned nsr, wcr;
+
+	spin_lock_irqsave(&db->lock, flags);
+
+	nsr = ior(db, DM9000_NSR);
+	wcr = ior(db, DM9000_WCR);
+
+	dev_dbg(db->dev, "%s: NSR=0x%02x, WCR=0x%02x\n", __func__, nsr, wcr);
+
+	if (nsr & NSR_WAKEST) {
+		/* clear, so we can avoid */
+		iow(db, DM9000_NSR, NSR_WAKEST);
+
+		if (wcr & WCR_LINKST)
+			dev_info(db->dev, "wake by link status change\n");
+		if (wcr & WCR_SAMPLEST)
+			dev_info(db->dev, "wake by sample packet\n");
+		if (wcr & WCR_MAGICST )
+			dev_info(db->dev, "wake by magic packet\n");
+		if (!(wcr & (WCR_LINKST | WCR_SAMPLEST | WCR_MAGICST)))
+			dev_err(db->dev, "wake signalled with no reason? "
+				"NSR=0x%02x, WSR=0x%02x\n", nsr, wcr);
+
+	}
+
+	spin_unlock_irqrestore(&db->lock, flags);
+
+	return (nsr & NSR_WAKEST) ? IRQ_HANDLED : IRQ_NONE;
+}
+
 #ifdef CONFIG_NET_POLL_CONTROLLER
 /*
  *Used by netconsole
···
 		goto out;
 	}
 
+	db->irq_wake = platform_get_irq(pdev, 1);
+	if (db->irq_wake >= 0) {
+		dev_dbg(db->dev, "wakeup irq %d\n", db->irq_wake);
+
+		ret = request_irq(db->irq_wake, dm9000_wol_interrupt,
+				  IRQF_SHARED, dev_name(db->dev), ndev);
+		if (ret) {
+			dev_err(db->dev, "cannot get wakeup irq (%d)\n", ret);
+		} else {
+
+			/* test to see if irq is really wakeup capable */
+			ret = set_irq_wake(db->irq_wake, 1);
+			if (ret) {
+				dev_err(db->dev, "irq %d cannot set wakeup (%d)\n",
+					db->irq_wake, ret);
+				ret = 0;
+			} else {
+				set_irq_wake(db->irq_wake, 0);
+				db->wake_supported = 1;
+			}
+		}
+	}
+
 	iosize = resource_size(db->addr_res);
 	db->addr_req = request_mem_region(db->addr_res->start, iosize,
 					  pdev->name);
···
 		db = netdev_priv(ndev);
 		db->in_suspend = 1;
 
-		if (netif_running(ndev)) {
-			netif_device_detach(ndev);
+		if (!netif_running(ndev))
+			return 0;
+
+		netif_device_detach(ndev);
+
+		/* only shutdown if not using WoL */
+		if (!db->wake_state)
 			dm9000_shutdown(ndev);
-		}
 	}
 	return 0;
 }
···
 	board_info_t *db = netdev_priv(ndev);
 
 	if (ndev) {
-
 		if (netif_running(ndev)) {
-			dm9000_reset(db);
-			dm9000_init_dm9000(ndev);
+			/* reset if we were not in wake mode to ensure if
+			 * the device was powered off it is in a known state */
+			if (!db->wake_state) {
+				dm9000_reset(db);
+				dm9000_init_dm9000(ndev);
+			}
 
 			netif_device_attach(ndev);
 		}

drivers/net/dm9000.h

···
 #define RSR_CE              (1<<1)
 #define RSR_FOE             (1<<0)
 
+#define WCR_LINKEN		(1 << 5)
+#define WCR_SAMPLEEN		(1 << 4)
+#define WCR_MAGICEN		(1 << 3)
+#define WCR_LINKST		(1 << 2)
+#define WCR_SAMPLEST		(1 << 1)
+#define WCR_MAGICST		(1 << 0)
+
 #define FCTR_HWOT(ot)	(( ot & 0xf ) << 4 )
 #define FCTR_LWOT(ot)	( ot & 0xf )