[PATCH] PHY Layer fixup

This patch adds back the code that was taken out, thus re-enabling:

* The PHY Layer to initialize without crashing
* Drivers to actually connect to PHYs
* The entire PHY Control Layer

This patch is used by the gianfar driver, and other drivers which are in
development.

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 253 insertions, 72 deletions

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index d3e43631b89..d9e11f93bf3 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -39,10 +39,20 @@
 #include <asm/irq.h>
 #include <asm/uaccess.h>
 
-static void phy_timer(unsigned long data);
-static int phy_disable_interrupts(struct phy_device *phydev);
-static void phy_sanitize_settings(struct phy_device *phydev);
-static int phy_stop_interrupts(struct phy_device *phydev);
+/* Convenience function to print out the current phy status
+ */
+void phy_print_status(struct phy_device *phydev)
+{
+	pr_info("%s: Link is %s", phydev->dev.bus_id,
+			phydev->link ? "Up" : "Down");
+	if (phydev->link)
+		printk(" - %d/%s", phydev->speed,
+				DUPLEX_FULL == phydev->duplex ?
+				"Full" : "Half");
+
+	printk("\n");
+}
+EXPORT_SYMBOL(phy_print_status);
 
 
 /* Convenience functions for reading/writing a given PHY
@@ -114,42 +124,6 @@ static inline int phy_aneg_done(struct phy_device *phydev)
 	return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
 }
 
-/* phy_start_aneg
- *
- * description: Calls the PHY driver's config_aneg, and then
- *   sets the PHY state to PHY_AN if auto-negotiation is enabled,
- *   and to PHY_FORCING if auto-negotiation is disabled. Unless
- *   the PHY is currently HALTED.
- */
-static int phy_start_aneg(struct phy_device *phydev)
-{
-	int err;
-
-	spin_lock(&phydev->lock);
-
-	if (AUTONEG_DISABLE == phydev->autoneg)
-		phy_sanitize_settings(phydev);
-
-	err = phydev->drv->config_aneg(phydev);
-
-	if (err < 0)
-		goto out_unlock;
-
-	if (phydev->state != PHY_HALTED) {
-		if (AUTONEG_ENABLE == phydev->autoneg) {
-			phydev->state = PHY_AN;
-			phydev->link_timeout = PHY_AN_TIMEOUT;
-		} else {
-			phydev->state = PHY_FORCING;
-			phydev->link_timeout = PHY_FORCE_TIMEOUT;
-		}
-	}
-
-out_unlock:
-	spin_unlock(&phydev->lock);
-	return err;
-}
-
 /* A structure for mapping a particular speed and duplex
  * combination to a particular SUPPORTED and ADVERTISED value */
 struct phy_setting {
@@ -241,7 +215,7 @@ static inline int phy_find_valid(int idx, u32 features)
  *   duplexes.  Drop down by one in this order:  1000/FULL,
  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF
  */
-static void phy_sanitize_settings(struct phy_device *phydev)
+void phy_sanitize_settings(struct phy_device *phydev)
 {
 	u32 features = phydev->supported;
 	int idx;
@@ -256,31 +230,7 @@ static void phy_sanitize_settings(struct phy_device *phydev)
 	phydev->speed = settings[idx].speed;
 	phydev->duplex = settings[idx].duplex;
 }
-
-/* phy_force_reduction
- *
- * description: Reduces the speed/duplex settings by
- *   one notch.  The order is so:
- *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF,
- *   10/FULL, 10/HALF.  The function bottoms out at 10/HALF.
- */
-static void phy_force_reduction(struct phy_device *phydev)
-{
-	int idx;
-
-	idx = phy_find_setting(phydev->speed, phydev->duplex);
-	
-	idx++;
-
-	idx = phy_find_valid(idx, phydev->supported);
-
-	phydev->speed = settings[idx].speed;
-	phydev->duplex = settings[idx].duplex;
-
-	pr_info("Trying %d/%s\n", phydev->speed,
-			DUPLEX_FULL == phydev->duplex ?
-			"FULL" : "HALF");
-}
+EXPORT_SYMBOL(phy_sanitize_settings);
 
 /* phy_ethtool_sset:
  * A generic ethtool sset function.  Handles all the details
@@ -291,6 +241,11 @@ static void phy_force_reduction(struct phy_device *phydev)
  * - phy_start_aneg() will make sure forced settings are sane, and
  *   choose the next best ones from the ones selected, so we don't
  *   care if ethtool tries to give us bad values
+ *
+ * A note about the PHYCONTROL Layer.  If you turn off
+ * CONFIG_PHYCONTROL, you will need to read the PHY status
+ * registers after this function completes, and update your
+ * controller manually.
  */
 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 {
@@ -406,6 +361,51 @@ int phy_mii_ioctl(struct phy_device *phydev,
 	return 0;
 }
 
+/* phy_start_aneg
+ *
+ * description: Sanitizes the settings (if we're not
+ *   autonegotiating them), and then calls the driver's
+ *   config_aneg function.  If the PHYCONTROL Layer is operating,
+ *   we change the state to reflect the beginning of
+ *   Auto-negotiation or forcing.
+ */
+int phy_start_aneg(struct phy_device *phydev)
+{
+	int err;
+
+	spin_lock(&phydev->lock);
+
+	if (AUTONEG_DISABLE == phydev->autoneg)
+		phy_sanitize_settings(phydev);
+
+	err = phydev->drv->config_aneg(phydev);
+
+#ifdef CONFIG_PHYCONTROL
+	if (err < 0)
+		goto out_unlock;
+
+	if (phydev->state != PHY_HALTED) {
+		if (AUTONEG_ENABLE == phydev->autoneg) {
+			phydev->state = PHY_AN;
+			phydev->link_timeout = PHY_AN_TIMEOUT;
+		} else {
+			phydev->state = PHY_FORCING;
+			phydev->link_timeout = PHY_FORCE_TIMEOUT;
+		}
+	}
+
+out_unlock:
+#endif
+	spin_unlock(&phydev->lock);
+	return err;
+}
+EXPORT_SYMBOL(phy_start_aneg);
+
+
+#ifdef CONFIG_PHYCONTROL
+static void phy_change(void *data);
+static void phy_timer(unsigned long data);
+
 /* phy_start_machine:
  *
  * description: The PHY infrastructure can run a state machine
@@ -448,6 +448,32 @@ void phy_stop_machine(struct phy_device *phydev)
 	phydev->adjust_state = NULL;
 }
 
+/* phy_force_reduction
+ *
+ * description: Reduces the speed/duplex settings by
+ *   one notch.  The order is so:
+ *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF,
+ *   10/FULL, 10/HALF.  The function bottoms out at 10/HALF.
+ */
+static void phy_force_reduction(struct phy_device *phydev)
+{
+	int idx;
+
+	idx = phy_find_setting(phydev->speed, phydev->duplex);
+	
+	idx++;
+
+	idx = phy_find_valid(idx, phydev->supported);
+
+	phydev->speed = settings[idx].speed;
+	phydev->duplex = settings[idx].duplex;
+
+	pr_info("Trying %d/%s\n", phydev->speed,
+			DUPLEX_FULL == phydev->duplex ?
+			"FULL" : "HALF");
+}
+
+
 /* phy_error:
  *
  * Moves the PHY to the HALTED state in response to a read
@@ -462,22 +488,44 @@ void phy_error(struct phy_device *phydev)
 	spin_unlock(&phydev->lock);
 }
 
-static int phy_stop_interrupts(struct phy_device *phydev)
+/* phy_interrupt
+ *
+ * description: When a PHY interrupt occurs, the handler disables
+ * interrupts, and schedules a work task to clear the interrupt.
+ */
+static irqreturn_t phy_interrupt(int irq, void *phy_dat, struct pt_regs *regs)
+{
+	struct phy_device *phydev = phy_dat;
+
+	/* The MDIO bus is not allowed to be written in interrupt
+	 * context, so we need to disable the irq here.  A work
+	 * queue will write the PHY to disable and clear the
+	 * interrupt, and then reenable the irq line. */
+	disable_irq_nosync(irq);
+
+	schedule_work(&phydev->phy_queue);
+
+	return IRQ_HANDLED;
+}
+
+/* Enable the interrupts from the PHY side */
+int phy_enable_interrupts(struct phy_device *phydev)
 {
 	int err;
 
-	err = phy_disable_interrupts(phydev);
+	err = phy_clear_interrupt(phydev);
 
-	if (err)
-		phy_error(phydev);
+	if (err < 0)
+		return err;
 
-	free_irq(phydev->irq, phydev);
+	err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 
 	return err;
 }
+EXPORT_SYMBOL(phy_enable_interrupts);
 
 /* Disable the PHY interrupts from the PHY side */
-static int phy_disable_interrupts(struct phy_device *phydev)
+int phy_disable_interrupts(struct phy_device *phydev)
 {
 	int err;
 
@@ -500,6 +548,138 @@ phy_err:
 
 	return err;
 }
+EXPORT_SYMBOL(phy_disable_interrupts);
+
+/* phy_start_interrupts
+ *
+ * description: Request the interrupt for the given PHY.  If
+ *   this fails, then we set irq to PHY_POLL.
+ *   Otherwise, we enable the interrupts in the PHY.
+ *   Returns 0 on success.
+ *   This should only be called with a valid IRQ number.
+ */
+int phy_start_interrupts(struct phy_device *phydev)
+{
+	int err = 0;
+
+	INIT_WORK(&phydev->phy_queue, phy_change, phydev);
+
+	if (request_irq(phydev->irq, phy_interrupt,
+				SA_SHIRQ,
+				"phy_interrupt",
+				phydev) < 0) {
+		printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
+				phydev->bus->name,
+				phydev->irq);
+		phydev->irq = PHY_POLL;
+		return 0;
+	}
+
+	err = phy_enable_interrupts(phydev);
+
+	return err;
+}
+EXPORT_SYMBOL(phy_start_interrupts);
+
+int phy_stop_interrupts(struct phy_device *phydev)
+{
+	int err;
+
+	err = phy_disable_interrupts(phydev);
+
+	if (err)
+		phy_error(phydev);
+
+	free_irq(phydev->irq, phydev);
+
+	return err;
+}
+EXPORT_SYMBOL(phy_stop_interrupts);
+
+
+/* Scheduled by the phy_interrupt/timer to handle PHY changes */
+static void phy_change(void *data)
+{
+	int err;
+	struct phy_device *phydev = data;
+
+	err = phy_disable_interrupts(phydev);
+
+	if (err)
+		goto phy_err;
+
+	spin_lock(&phydev->lock);
+	if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
+		phydev->state = PHY_CHANGELINK;
+	spin_unlock(&phydev->lock);
+
+	enable_irq(phydev->irq);
+
+	/* Reenable interrupts */
+	err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
+
+	if (err)
+		goto irq_enable_err;
+
+	return;
+
+irq_enable_err:
+	disable_irq(phydev->irq);
+phy_err:
+	phy_error(phydev);
+}
+
+/* Bring down the PHY link, and stop checking the status. */
+void phy_stop(struct phy_device *phydev)
+{
+	spin_lock(&phydev->lock);
+
+	if (PHY_HALTED == phydev->state)
+		goto out_unlock;
+
+	if (phydev->irq != PHY_POLL) {
+		/* Clear any pending interrupts */
+		phy_clear_interrupt(phydev);
+
+		/* Disable PHY Interrupts */
+		phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
+	}
+
+	phydev->state = PHY_HALTED;
+
+out_unlock:
+	spin_unlock(&phydev->lock);
+}
+
+
+/* phy_start
+ *
+ * description: Indicates the attached device's readiness to
+ *   handle PHY-related work.  Used during startup to start the
+ *   PHY, and after a call to phy_stop() to resume operation.
+ *   Also used to indicate the MDIO bus has cleared an error
+ *   condition.
+ */
+void phy_start(struct phy_device *phydev)
+{
+	spin_lock(&phydev->lock);
+
+	switch (phydev->state) {
+		case PHY_STARTING:
+			phydev->state = PHY_PENDING;
+			break;
+		case PHY_READY:
+			phydev->state = PHY_UP;
+			break;
+		case PHY_HALTED:
+			phydev->state = PHY_RESUMING;
+		default:
+			break;
+	}
+	spin_unlock(&phydev->lock);
+}
+EXPORT_SYMBOL(phy_stop);
+EXPORT_SYMBOL(phy_start);
 
 /* PHY timer which handles the state machine */
 static void phy_timer(unsigned long data)
@@ -688,3 +868,4 @@ static void phy_timer(unsigned long data)
 	mod_timer(&phydev->phy_timer, jiffies + PHY_STATE_TIME * HZ);
 }
 
+#endif /* CONFIG_PHYCONTROL */