Subject: Re: DM9000: Use delayed work to update MII PHY state

From: Andrew Morton <[email-masked]>
Date: Thu, 8 May 2008 13:18:29 -0700

On Thu, 8 May 2008 11:36:42 +0100
Ben Dooks <[email-masked]> wrote:

> Periodically check the MII PHY status to ensure that the
> network layer's link status is updated and the user informed
> of any changes.
> 
> Signed-off-by: Ben Dooks <[email-masked]>
> 
> Index: linux-2.6.25-rc9-quilt2/drivers/net/dm9000.c
> ===================================================================
> --- linux-2.6.25-rc9-quilt2.orig/drivers/net/dm9000.c	2008-04-14 16:41:12.000000000 +0100
> +++ linux-2.6.25-rc9-quilt2/drivers/net/dm9000.c	2008-04-15 00:33:08.000000000 +0100
> @@ -117,6 +117,9 @@ typedef struct board_info {
>  
>  	struct mutex	 addr_lock;	/* phy and eeprom access lock */
>  
> +	struct delayed_work phy_poll;
> +	struct net_device  *ndev;
> +
>  	spinlock_t lock;
>  
>  	struct mii_if_info mii;
> @@ -297,6 +300,10 @@ static void dm9000_set_io(struct board_i
>  	}
>  }
>  
> +static void dm9000_schedule_poll(board_info_t *db)
> +{
> +	schedule_delayed_work(&db->phy_poll, HZ * 2);
> +}
>  
>  /* Our watchdog timed out. Called by the networking layer */
>  static void dm9000_timeout(struct net_device *dev)
> @@ -465,6 +472,17 @@ static const struct ethtool_ops dm9000_e
>   	.set_eeprom		= dm9000_set_eeprom,
>  };
>  
> +static void
> +dm9000_poll_work(struct work_struct *w)
> +{
> +	struct delayed_work *dw = container_of(w, struct delayed_work, work);
> +	board_info_t *db = container_of(dw, board_info_t, phy_poll);
> +
> +	mii_check_media(&db->mii, netif_msg_link(db), 0);
> +	
> +	if (netif_running(db->ndev))
> +		dm9000_schedule_poll(db);
> +}
>  
>  /* dm9000_release_board
>   *
> @@ -532,10 +550,14 @@ dm9000_probe(struct platform_device *pde
>  	memset(db, 0, sizeof (*db));
>  
>  	db->dev = &pdev->dev;
> +	db->ndev = ndev;
>  
>  	spin_lock_init(&db->lock);
>  	mutex_init(&db->addr_lock);
>  
> +	INIT_DELAYED_WORK(&db->phy_poll, dm9000_poll_work);
> +
> +
>  	if (pdev->num_resources < 2) {
>  		ret = -ENODEV;
>  		goto out;
> @@ -761,6 +783,8 @@ dm9000_open(struct net_device *dev)
>  
>  	mii_check_media(&db->mii, netif_msg_link(db), 1);
>  	netif_start_queue(dev);
> +	
> +	dm9000_schedule_poll(db);
>  
>  	return 0;
>  }
> @@ -879,6 +903,8 @@ dm9000_stop(struct net_device *ndev)
>  	if (netif_msg_ifdown(db))
>  		dev_dbg(db->dev, "shutting down %s\n", ndev->name);
>  
> +	cancel_delayed_work(&db->phy_poll);
> +
>  	netif_stop_queue(ndev);
>  	netif_carrier_off(ndev);
>  

The above patch breaks dm9000-restore-mii-physical-polling-timer.patch,
below.

Perhaps they both fix the same thing?

From: Michael Abbott <[email-masked]>

In commit fcfa81aa3e8d885356139122fcb281487b983468 the timer for polling the
MII physical layer was removed because of conflicts with newly added mutexes. 
Unfortunately a side effect of this change is that the corresponding ethernet
layer is permanently reported as down: there is no other way to read the link
status.

This commit restores the timer, but uses the default work queue for polling.

Signed-off-by: Michael Abbott <[email-masked]>
Cc: Daniel Mack <[email-masked]>
Cc: Russell King <[email-masked]>
Cc: Jeff Garzik <[email-masked]>
Cc: Ben Dooks <[email-masked]>
Signed-off-by: Andrew Morton <[email-masked]>
---

 drivers/net/dm9000.c |   21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff -puN drivers/net/dm9000.c~dm9000-restore-mii-physical-polling-timer drivers/net/dm9000.c
--- a/drivers/net/dm9000.c~dm9000-restore-mii-physical-polling-timer
+++ a/drivers/net/dm9000.c
@@ -43,6 +43,7 @@
 /* Board/System/Debug information/definition ---------------- */
 
 #define DM9000_PHY		0x40	/* PHY address 0x01 */
+#define DM9000_TIMER_WUT	(HZ*2)	/* timer wakeup time : 2 second */
 
 #define CARDNAME "dm9000"
 #define PFX CARDNAME ": "
@@ -117,6 +118,8 @@ typedef struct board_info {
 
 	struct mutex	 addr_lock;	/* phy and eeprom access lock */
 
+	struct delayed_work timer;	/* Interface status timer. */
+
 	spinlock_t lock;
 
 	struct mii_if_info mii;
@@ -144,6 +147,7 @@ static int dm9000_start_xmit(struct sk_b
 static int dm9000_stop(struct net_device *);
 static int dm9000_ioctl(struct net_device *dev, struct ifreq *req, int cmd);
 
+static void dm9000_timer(struct work_struct * work);
 static void dm9000_init_dm9000(struct net_device *);
 
 static irqreturn_t dm9000_interrupt(int, void *);
@@ -762,6 +766,10 @@ dm9000_open(struct net_device *dev)
 	mii_check_media(&db->mii, netif_msg_link(db), 1);
 	netif_start_queue(dev);
 
+	/* Start the media status timer running. */
+	INIT_DELAYED_WORK(&db->timer, dm9000_timer);
+	schedule_delayed_work(&db->timer, DM9000_TIMER_WUT);
+
 	return 0;
 }
 
@@ -876,6 +884,9 @@ dm9000_stop(struct net_device *ndev)
 {
 	board_info_t *db = (board_info_t *) ndev->priv;
 
+	/* Delete the timer and make sure it's not running right now! */
+	cancel_delayed_work_sync(&db->timer);
+
 	if (netif_msg_ifdown(db))
 		dev_dbg(db->dev, "shutting down %s\n", ndev->name);
 
@@ -965,6 +976,16 @@ dm9000_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+
+/* Two second timer to poll the media status -- the DM9000 doesn't provide a
+ * status interrupt, so this has to be polled. */
+static void dm9000_timer(struct work_struct * work)
+{
+	board_info_t *db = container_of(work, board_info_t, timer);
+	mii_check_media(&db->mii, netif_msg_link(db), 0);
+	schedule_delayed_work(&db->timer, DM9000_TIMER_WUT);
+}
+
 struct dm9000_rxhdr {
 	u8	RxPktReady;
 	u8	RxStatus;
_