Merge branch 'lan95xx-no-polling'

Lukas Wunner says:

====================
Polling be gone on LAN95xx

Do away with link status polling on LAN95xx USB Ethernet
and rely on interrupts instead, thereby reducing bus traffic,
CPU overhead and improving interface bringup latency.

Link to v2:
https://lore.kernel.org/netdev/cover.1651574194.git.lukas@wunner.de/

Only change since v2:

* Patch [5/7]:
  * Drop call to __irq_enter_raw() which worked around a warning in
    generic_handle_domain_irq().  That warning is gone since
    792ea6a074ae (queued on tip.git/irq/urgent).
    (Marc Zyngier, Thomas Gleixner)
====================

4 files changed, 88 insertions, 104 deletions

diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c
index 92225d0fc246..1b54684b68a0 100644
--- a/drivers/net/phy/smsc.c
+++ b/drivers/net/phy/smsc.c
@@ -44,6 +44,7 @@ static struct smsc_hw_stat smsc_hw_stats[] = {
 };
 
 struct smsc_phy_priv {
+	u16 intmask;
 	bool energy_enable;
 	struct clk *refclk;
 };
@@ -58,7 +59,6 @@ static int smsc_phy_ack_interrupt(struct phy_device *phydev)
 static int smsc_phy_config_intr(struct phy_device *phydev)
 {
 	struct smsc_phy_priv *priv = phydev->priv;
-	u16 intmask = 0;
 	int rc;
 
 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
@@ -66,12 +66,15 @@ static int smsc_phy_config_intr(struct phy_device *phydev)
 		if (rc)
 			return rc;
 
-		intmask = MII_LAN83C185_ISF_INT4 | MII_LAN83C185_ISF_INT6;
+		priv->intmask = MII_LAN83C185_ISF_INT4 | MII_LAN83C185_ISF_INT6;
 		if (priv->energy_enable)
-			intmask |= MII_LAN83C185_ISF_INT7;
-		rc = phy_write(phydev, MII_LAN83C185_IM, intmask);
+			priv->intmask |= MII_LAN83C185_ISF_INT7;
+
+		rc = phy_write(phydev, MII_LAN83C185_IM, priv->intmask);
 	} else {
-		rc = phy_write(phydev, MII_LAN83C185_IM, intmask);
+		priv->intmask = 0;
+
+		rc = phy_write(phydev, MII_LAN83C185_IM, 0);
 		if (rc)
 			return rc;
 
@@ -83,21 +86,18 @@ static int smsc_phy_config_intr(struct phy_device *phydev)
 
 static irqreturn_t smsc_phy_handle_interrupt(struct phy_device *phydev)
 {
-	int irq_status, irq_enabled;
-
-	irq_enabled = phy_read(phydev, MII_LAN83C185_IM);
-	if (irq_enabled < 0) {
-		phy_error(phydev);
-		return IRQ_NONE;
-	}
+	struct smsc_phy_priv *priv = phydev->priv;
+	int irq_status;
 
 	irq_status = phy_read(phydev, MII_LAN83C185_ISF);
 	if (irq_status < 0) {
-		phy_error(phydev);
+		if (irq_status != -ENODEV)
+			phy_error(phydev);
+
 		return IRQ_NONE;
 	}
 
-	if (!(irq_status & irq_enabled))
+	if (!(irq_status & priv->intmask))
 		return IRQ_NONE;
 
 	phy_trigger_machine(phydev);
diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
index 38e47a93fb83..5b5eb630c4b7 100644
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -795,11 +795,7 @@ static int ax88772_stop(struct usbnet *dev)
 {
 	struct asix_common_private *priv = dev->driver_priv;
 
-	/* On unplugged USB, we will get MDIO communication errors and the
-	 * PHY will be set in to PHY_HALTED state.
-	 */
-	if (priv->phydev->state != PHY_HALTED)
-		phy_stop(priv->phydev);
+	phy_stop(priv->phydev);
 
 	return 0;
 }
diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index 4ef61f6b85df..bd03e16f98a1 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -18,6 +18,8 @@
 #include <linux/usb/usbnet.h>
 #include <linux/slab.h>
 #include <linux/of_net.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/mdio.h>
 #include <linux/phy.h>
 #include <net/selftests.h>
@@ -53,6 +55,9 @@
 #define SUSPEND_ALLMODES		(SUSPEND_SUSPEND0 | SUSPEND_SUSPEND1 | \
 					 SUSPEND_SUSPEND2 | SUSPEND_SUSPEND3)
 
+#define SMSC95XX_NR_IRQS		(1) /* raise to 12 for GPIOs */
+#define PHY_HWIRQ			(SMSC95XX_NR_IRQS - 1)
+
 struct smsc95xx_priv {
 	u32 mac_cr;
 	u32 hash_hi;
@@ -61,6 +66,9 @@ struct smsc95xx_priv {
 	spinlock_t mac_cr_lock;
 	u8 features;
 	u8 suspend_flags;
+	struct irq_chip irqchip;
+	struct irq_domain *irqdomain;
+	struct fwnode_handle *irqfwnode;
 	struct mii_bus *mdiobus;
 	struct phy_device *phydev;
 };
@@ -566,16 +574,12 @@ static int smsc95xx_phy_update_flowcontrol(struct usbnet *dev)
 	return smsc95xx_write_reg(dev, AFC_CFG, afc_cfg);
 }
 
-static int smsc95xx_link_reset(struct usbnet *dev)
+static void smsc95xx_mac_update_fullduplex(struct usbnet *dev)
 {
 	struct smsc95xx_priv *pdata = dev->driver_priv;
 	unsigned long flags;
 	int ret;
 
-	ret = smsc95xx_write_reg(dev, INT_STS, INT_STS_CLEAR_ALL_);
-	if (ret < 0)
-		return ret;
-
 	spin_lock_irqsave(&pdata->mac_cr_lock, flags);
 	if (pdata->phydev->duplex != DUPLEX_FULL) {
 		pdata->mac_cr &= ~MAC_CR_FDPX_;
@@ -587,18 +591,22 @@ static int smsc95xx_link_reset(struct usbnet *dev)
 	spin_unlock_irqrestore(&pdata->mac_cr_lock, flags);
 
 	ret = smsc95xx_write_reg(dev, MAC_CR, pdata->mac_cr);
-	if (ret < 0)
-		return ret;
+	if (ret < 0) {
+		if (ret != -ENODEV)
+			netdev_warn(dev->net,
+				    "Error updating MAC full duplex mode\n");
+		return;
+	}
 
 	ret = smsc95xx_phy_update_flowcontrol(dev);
 	if (ret < 0)
 		netdev_warn(dev->net, "Error updating PHY flow control\n");
-
-	return ret;
 }
 
 static void smsc95xx_status(struct usbnet *dev, struct urb *urb)
 {
+	struct smsc95xx_priv *pdata = dev->driver_priv;
+	unsigned long flags;
 	u32 intdata;
 
 	if (urb->actual_length != 4) {
@@ -610,11 +618,15 @@ static void smsc95xx_status(struct usbnet *dev, struct urb *urb)
 	intdata = get_unaligned_le32(urb->transfer_buffer);
 	netif_dbg(dev, link, dev->net, "intdata: 0x%08X\n", intdata);
 
+	local_irq_save(flags);
+
 	if (intdata & INT_ENP_PHY_INT_)
-		usbnet_defer_kevent(dev, EVENT_LINK_RESET);
+		generic_handle_domain_irq(pdata->irqdomain, PHY_HWIRQ);
 	else
 		netdev_warn(dev->net, "unexpected interrupt, intdata=0x%08X\n",
 			    intdata);
+
+	local_irq_restore(flags);
 }
 
 /* Enable or disable Tx & Rx checksum offload engines */
@@ -891,24 +903,6 @@ static int smsc95xx_reset(struct usbnet *dev)
 		return ret;
 	}
 
-	ret = smsc95xx_write_reg(dev, PM_CTRL, PM_CTL_PHY_RST_);
-	if (ret < 0)
-		return ret;
-
-	timeout = 0;
-	do {
-		msleep(10);
-		ret = smsc95xx_read_reg(dev, PM_CTRL, &read_buf);
-		if (ret < 0)
-			return ret;
-		timeout++;
-	} while ((read_buf & PM_CTL_PHY_RST_) && (timeout < 100));
-
-	if (timeout >= 100) {
-		netdev_warn(dev->net, "timeout waiting for PHY Reset\n");
-		return ret;
-	}
-
 	ret = smsc95xx_set_mac_address(dev);
 	if (ret < 0)
 		return ret;
@@ -1092,6 +1086,7 @@ static void smsc95xx_handle_link_change(struct net_device *net)
 	struct usbnet *dev = netdev_priv(net);
 
 	phy_print_status(net->phydev);
+	smsc95xx_mac_update_fullduplex(dev);
 	usbnet_defer_kevent(dev, EVENT_LINK_CHANGE);
 }
 
@@ -1099,8 +1094,9 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf)
 {
 	struct smsc95xx_priv *pdata;
 	bool is_internal_phy;
+	char usb_path[64];
+	int ret, phy_irq;
 	u32 val;
-	int ret;
 
 	printk(KERN_INFO SMSC_CHIPNAME " v" SMSC_DRIVER_VERSION "\n");
 
@@ -1140,10 +1136,38 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf)
 	if (ret)
 		goto free_pdata;
 
+	/* create irq domain for use by PHY driver and GPIO consumers */
+	usb_make_path(dev->udev, usb_path, sizeof(usb_path));
+	pdata->irqfwnode = irq_domain_alloc_named_fwnode(usb_path);
+	if (!pdata->irqfwnode) {
+		ret = -ENOMEM;
+		goto free_pdata;
+	}
+
+	pdata->irqdomain = irq_domain_create_linear(pdata->irqfwnode,
+						    SMSC95XX_NR_IRQS,
+						    &irq_domain_simple_ops,
+						    pdata);
+	if (!pdata->irqdomain) {
+		ret = -ENOMEM;
+		goto free_irqfwnode;
+	}
+
+	phy_irq = irq_create_mapping(pdata->irqdomain, PHY_HWIRQ);
+	if (!phy_irq) {
+		ret = -ENOENT;
+		goto remove_irqdomain;
+	}
+
+	pdata->irqchip = dummy_irq_chip;
+	pdata->irqchip.name = SMSC_CHIPNAME;
+	irq_set_chip_and_handler_name(phy_irq, &pdata->irqchip,
+				      handle_simple_irq, "phy");
+
 	pdata->mdiobus = mdiobus_alloc();
 	if (!pdata->mdiobus) {
 		ret = -ENOMEM;
-		goto free_pdata;
+		goto dispose_irq;
 	}
 
 	ret = smsc95xx_read_reg(dev, HW_CFG, &val);
@@ -1176,6 +1200,7 @@ static int smsc95xx_bind(struct usbnet *dev, struct usb_interface *intf)
 		goto unregister_mdio;
 	}
 
+	pdata->phydev->irq = phy_irq;
 	pdata->phydev->is_internal = is_internal_phy;
 
 	/* detect device revision as different features may be available */
@@ -1218,6 +1243,15 @@ unregister_mdio:
 free_mdio:
 	mdiobus_free(pdata->mdiobus);
 
+dispose_irq:
+	irq_dispose_mapping(phy_irq);
+
+remove_irqdomain:
+	irq_domain_remove(pdata->irqdomain);
+
+free_irqfwnode:
+	irq_domain_free_fwnode(pdata->irqfwnode);
+
 free_pdata:
 	kfree(pdata);
 	return ret;
@@ -1230,6 +1264,9 @@ static void smsc95xx_unbind(struct usbnet *dev, struct usb_interface *intf)
 	phy_disconnect(dev->net->phydev);
 	mdiobus_unregister(pdata->mdiobus);
 	mdiobus_free(pdata->mdiobus);
+	irq_dispose_mapping(irq_find_mapping(pdata->irqdomain, PHY_HWIRQ));
+	irq_domain_remove(pdata->irqdomain);
+	irq_domain_free_fwnode(pdata->irqfwnode);
 	netif_dbg(dev, ifdown, dev->net, "free pdata\n");
 	kfree(pdata);
 }
@@ -1243,8 +1280,7 @@ static int smsc95xx_start_phy(struct usbnet *dev)
 
 static int smsc95xx_stop(struct usbnet *dev)
 {
-	if (dev->net->phydev)
-		phy_stop(dev->net->phydev);
+	phy_stop(dev->net->phydev);
 
 	return 0;
 }
@@ -1255,29 +1291,6 @@ static u32 smsc_crc(const u8 *buffer, size_t len, int filter)
 	return crc << ((filter % 2) * 16);
 }
 
-static int smsc95xx_enable_phy_wakeup_interrupts(struct usbnet *dev, u16 mask)
-{
-	int ret;
-
-	netdev_dbg(dev->net, "enabling PHY wakeup interrupts\n");
-
-	/* read to clear */
-	ret = smsc95xx_mdio_read_nopm(dev, PHY_INT_SRC);
-	if (ret < 0)
-		return ret;
-
-	/* enable interrupt source */
-	ret = smsc95xx_mdio_read_nopm(dev, PHY_INT_MASK);
-	if (ret < 0)
-		return ret;
-
-	ret |= mask;
-
-	smsc95xx_mdio_write_nopm(dev, PHY_INT_MASK, ret);
-
-	return 0;
-}
-
 static int smsc95xx_link_ok_nopm(struct usbnet *dev)
 {
 	int ret;
@@ -1444,7 +1457,6 @@ static int smsc95xx_enter_suspend3(struct usbnet *dev)
 static int smsc95xx_autosuspend(struct usbnet *dev, u32 link_up)
 {
 	struct smsc95xx_priv *pdata = dev->driver_priv;
-	int ret;
 
 	if (!netif_running(dev->net)) {
 		/* interface is ifconfig down so fully power down hw */
@@ -1463,27 +1475,10 @@ static int smsc95xx_autosuspend(struct usbnet *dev, u32 link_up)
 		}
 
 		netdev_dbg(dev->net, "autosuspend entering SUSPEND1\n");
-
-		/* enable PHY wakeup events for if cable is attached */
-		ret = smsc95xx_enable_phy_wakeup_interrupts(dev,
-			PHY_INT_MASK_ANEG_COMP_);
-		if (ret < 0) {
-			netdev_warn(dev->net, "error enabling PHY wakeup ints\n");
-			return ret;
-		}
-
 		netdev_info(dev->net, "entering SUSPEND1 mode\n");
 		return smsc95xx_enter_suspend1(dev);
 	}
 
-	/* enable PHY wakeup events so we remote wakeup if cable is pulled */
-	ret = smsc95xx_enable_phy_wakeup_interrupts(dev,
-		PHY_INT_MASK_LINK_DOWN_);
-	if (ret < 0) {
-		netdev_warn(dev->net, "error enabling PHY wakeup ints\n");
-		return ret;
-	}
-
 	netdev_dbg(dev->net, "autosuspend entering SUSPEND3\n");
 	return smsc95xx_enter_suspend3(dev);
 }
@@ -1549,13 +1544,6 @@ static int smsc95xx_suspend(struct usb_interface *intf, pm_message_t message)
 	}
 
 	if (pdata->wolopts & WAKE_PHY) {
-		ret = smsc95xx_enable_phy_wakeup_interrupts(dev,
-			(PHY_INT_MASK_ANEG_COMP_ | PHY_INT_MASK_LINK_DOWN_));
-		if (ret < 0) {
-			netdev_warn(dev->net, "error enabling PHY wakeup ints\n");
-			goto done;
-		}
-
 		/* if link is down then configure EDPD and enter SUSPEND1,
 		 * otherwise enter SUSPEND0 below
 		 */
@@ -1789,11 +1777,12 @@ static int smsc95xx_resume(struct usb_interface *intf)
 			return ret;
 	}
 
+	phy_init_hw(pdata->phydev);
+
 	ret = usbnet_resume(intf);
 	if (ret < 0)
 		netdev_warn(dev->net, "usbnet_resume error\n");
 
-	phy_init_hw(pdata->phydev);
 	return ret;
 }
 
@@ -1998,7 +1987,6 @@ static const struct driver_info smsc95xx_info = {
 	.description	= "smsc95xx USB 2.0 Ethernet",
 	.bind		= smsc95xx_bind,
 	.unbind		= smsc95xx_unbind,
-	.link_reset	= smsc95xx_link_reset,
 	.reset		= smsc95xx_reset,
 	.check_connect	= smsc95xx_start_phy,
 	.stop		= smsc95xx_stop,
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index 9a6450f796dc..36b24ec11650 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1616,9 +1616,6 @@ void usbnet_disconnect (struct usb_interface *intf)
 		   xdev->bus->bus_name, xdev->devpath,
 		   dev->driver_info->description);
 
-	if (dev->driver_info->unbind)
-		dev->driver_info->unbind(dev, intf);
-
 	net = dev->net;
 	unregister_netdev (net);
 
@@ -1626,6 +1623,9 @@ void usbnet_disconnect (struct usb_interface *intf)
 
 	usb_scuttle_anchored_urbs(&dev->deferred);
 
+	if (dev->driver_info->unbind)
+		dev->driver_info->unbind(dev, intf);
+
 	usb_kill_urb(dev->interrupt);
 	usb_free_urb(dev->interrupt);
 	kfree(dev->padding_pkt);