[PATCH v3 0/3] lan78xx: Read configuration from Device Tree

[PATCH v3 0/3] lan78xx: Read configuration from Device Tree

[Phil Elwell]

The Microchip LAN78XX family of devices are Ethernet controllers with
a USB interface. Despite being discoverable devices it can be useful to
be able to configure them from Device Tree, particularly in low-cost
applications without an EEPROM or programmed OTP.

This patch set adds support for reading the MAC address and LED modes from
Device Tree.

v3:
- Move LED setting into PHY driver.

v2:
- Use eth_platform_get_mac_address.
- Support up to 4 LEDs, and move LED mode constants into dt-bindings header.
- Improve bindings document.
- Remove EEE support.

Phil Elwell (3):
  lan78xx: Read MAC address from DT if present
  lan78xx: Read LED states from Device Tree
  dt-bindings: Document the DT bindings for lan78xx

 .../devicetree/bindings/net/microchip,lan78xx.txt  | 54 ++++++++++++++++
 MAINTAINERS                                        |  2 +
 drivers/net/phy/microchip.c                        | 25 ++++++++
 drivers/net/usb/lan78xx.c                          | 74 +++++++++++++++-------
 include/dt-bindings/net/microchip-lan78xx.h        | 21 ++++++
 include/linux/microchipphy.h                       |  3 +
 6 files changed, 156 insertions(+), 23 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/microchip,lan78xx.txt
 create mode 100644 include/dt-bindings/net/microchip-lan78xx.h

-- 
2.7.4

[PATCH v3 0/3] lan78xx: Read configuration from Device Tree

[Phil Elwell]

The Microchip LAN78XX family of devices are Ethernet controllers with
a USB interface. Despite being discoverable devices it can be useful to
be able to configure them from Device Tree, particularly in low-cost
applications without an EEPROM or programmed OTP.

This patch set adds support for reading the MAC address and LED modes from
Device Tree.

v3:
- Move LED setting into PHY driver.

v2:
- Use eth_platform_get_mac_address.
- Support up to 4 LEDs, and move LED mode constants into dt-bindings header.
- Improve bindings document.
- Remove EEE support.

Phil Elwell (3):
  lan78xx: Read MAC address from DT if present
  lan78xx: Read LED states from Device Tree
  dt-bindings: Document the DT bindings for lan78xx

 .../devicetree/bindings/net/microchip,lan78xx.txt  | 54 ++++++++++++++++
 MAINTAINERS                                        |  2 +
 drivers/net/phy/microchip.c                        | 25 ++++++++
 drivers/net/usb/lan78xx.c                          | 74 +++++++++++++++-------
 include/dt-bindings/net/microchip-lan78xx.h        | 21 ++++++
 include/linux/microchipphy.h                       |  3 +
 6 files changed, 156 insertions(+), 23 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/microchip,lan78xx.txt
 create mode 100644 include/dt-bindings/net/microchip-lan78xx.h

-- 
2.7.4

[PATCH v3 1/3] lan78xx: Read MAC address from DT if present

[Phil Elwell]

There is a standard mechanism for locating and using a MAC address from
the Device Tree. Use this facility in the lan78xx driver to support
applications without programmed EEPROM or OTP. At the same time,
regularise the handling of the different address sources.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 drivers/net/usb/lan78xx.c | 42 ++++++++++++++++++++----------------------
 1 file changed, 20 insertions(+), 22 deletions(-)

diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 0867f72..a823f01 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -37,6 +37,7 @@
 #include <linux/irqchip/chained_irq.h>
 #include <linux/microchipphy.h>
 #include <linux/phy.h>
+#include <linux/of_net.h>
 #include "lan78xx.h"
 
 #define DRIVER_AUTHOR	"WOOJUNG HUH <woojung.huh@microchip.com>"
@@ -1652,34 +1653,31 @@ static void lan78xx_init_mac_address(struct lan78xx_net *dev)
 	addr[5] = (addr_hi >> 8) & 0xFF;
 
 	if (!is_valid_ether_addr(addr)) {
-		/* reading mac address from EEPROM or OTP */
-		if ((lan78xx_read_eeprom(dev, EEPROM_MAC_OFFSET, ETH_ALEN,
-					 addr) == 0) ||
-		    (lan78xx_read_otp(dev, EEPROM_MAC_OFFSET, ETH_ALEN,
-				      addr) == 0)) {
-			if (is_valid_ether_addr(addr)) {
-				/* eeprom values are valid so use them */
-				netif_dbg(dev, ifup, dev->net,
-					  "MAC address read from EEPROM");
-			} else {
-				/* generate random MAC */
-				random_ether_addr(addr);
-				netif_dbg(dev, ifup, dev->net,
-					  "MAC address set to random addr");
-			}
-
-			addr_lo = addr[0] | (addr[1] << 8) |
-				  (addr[2] << 16) | (addr[3] << 24);
-			addr_hi = addr[4] | (addr[5] << 8);
-
-			ret = lan78xx_write_reg(dev, RX_ADDRL, addr_lo);
-			ret = lan78xx_write_reg(dev, RX_ADDRH, addr_hi);
+		if (!eth_platform_get_mac_address(&dev->udev->dev, addr)) {
+			/* valid address present in Device Tree */
+			netif_dbg(dev, ifup, dev->net,
+				  "MAC address read from Device Tree");
+		} else if (((lan78xx_read_eeprom(dev, EEPROM_MAC_OFFSET,
+						 ETH_ALEN, addr) == 0) ||
+			    (lan78xx_read_otp(dev, EEPROM_MAC_OFFSET,
+					      ETH_ALEN, addr) == 0)) &&
+			   is_valid_ether_addr(addr)) {
+			/* eeprom values are valid so use them */
+			netif_dbg(dev, ifup, dev->net,
+				  "MAC address read from EEPROM");
 		} else {
 			/* generate random MAC */
 			random_ether_addr(addr);
 			netif_dbg(dev, ifup, dev->net,
 				  "MAC address set to random addr");
 		}
+
+		addr_lo = addr[0] | (addr[1] << 8) |
+			  (addr[2] << 16) | (addr[3] << 24);
+		addr_hi = addr[4] | (addr[5] << 8);
+
+		ret = lan78xx_write_reg(dev, RX_ADDRL, addr_lo);
+		ret = lan78xx_write_reg(dev, RX_ADDRH, addr_hi);
 	}
 
 	ret = lan78xx_write_reg(dev, MAF_LO(0), addr_lo);
-- 
2.7.4

[PATCH v3 2/3] lan78xx: Read LED states from Device Tree

[Phil Elwell]

Add support for DT property "microchip,led-modes", a vector of zero
to four cells (u32s) in the range 0-15, each of which sets the mode
for one of the LEDs. Some possible values are:

    0=link/activity          1=link1000/activity
    2=link100/activity       3=link10/activity
    4=link100/1000/activity  5=link10/1000/activity
    6=link10/100/activity    14=off    15=on

These values are given symbolic constants in a dt-bindings header.

Also use the presence of the DT property to indicate that the
LEDs should be enabled - necessary in the event that no valid OTP
or EEPROM is available.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 MAINTAINERS                                 |  1 +
 drivers/net/phy/microchip.c                 | 25 ++++++++++++++++++++++
 drivers/net/usb/lan78xx.c                   | 32 ++++++++++++++++++++++++++++-
 include/dt-bindings/net/microchip-lan78xx.h | 21 +++++++++++++++++++
 include/linux/microchipphy.h                |  3 +++
 5 files changed, 81 insertions(+), 1 deletion(-)
 create mode 100644 include/dt-bindings/net/microchip-lan78xx.h

diff --git a/MAINTAINERS b/MAINTAINERS
index b60179d..23735d9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14573,6 +14573,7 @@ M:	Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>
 L:	netdev@vger.kernel.org
 S:	Maintained
 F:	drivers/net/usb/lan78xx.*
+F:	include/dt-bindings/net/microchip-lan78xx.h
 
 USB MASS STORAGE DRIVER
 M:	Alan Stern <stern@rowland.harvard.edu>
diff --git a/drivers/net/phy/microchip.c b/drivers/net/phy/microchip.c
index 0f293ef..ef5e160 100644
--- a/drivers/net/phy/microchip.c
+++ b/drivers/net/phy/microchip.c
@@ -20,6 +20,8 @@
 #include <linux/ethtool.h>
 #include <linux/phy.h>
 #include <linux/microchipphy.h>
+#include <linux/of.h>
+#include <dt-bindings/net/microchip-lan78xx.h>
 
 #define DRIVER_AUTHOR	"WOOJUNG HUH <woojung.huh@microchip.com>"
 #define DRIVER_DESC	"Microchip LAN88XX PHY driver"
@@ -70,6 +72,8 @@ static int lan88xx_probe(struct phy_device *phydev)
 {
 	struct device *dev = &phydev->mdio.dev;
 	struct lan88xx_priv *priv;
+	u32 led_modes[4];
+	int len;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -77,6 +81,27 @@ static int lan88xx_probe(struct phy_device *phydev)
 
 	priv->wolopts = 0;
 
+	len = of_property_read_variable_u32_array(dev->of_node,
+						  "microchip,led-modes",
+						  led_modes,
+						  0,
+						  ARRAY_SIZE(led_modes));
+	if (len >= 0) {
+		u32 reg = 0;
+		int i;
+
+		for (i = 0; i < len; i++) {
+			if (led_modes[i] > 15)
+				return -EINVAL;
+			reg |= led_modes[i] << (i * 4);
+		}
+		for (; i < ARRAY_SIZE(led_modes); i++)
+			reg |= LAN78XX_FORCE_LED_OFF << (i * 4);
+		(void)phy_write(phydev, LAN78XX_PHY_LED_MODE_SELECT, reg);
+	} else if (len == -EOVERFLOW) {
+		return -EINVAL;
+	}
+
 	/* these values can be used to identify internal PHY */
 	priv->chip_id = phy_read_mmd(phydev, 3, LAN88XX_MMD3_CHIP_ID);
 	priv->chip_rev = phy_read_mmd(phydev, 3, LAN88XX_MMD3_CHIP_REV);
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index a823f01..6b03b97 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -37,6 +37,7 @@
 #include <linux/irqchip/chained_irq.h>
 #include <linux/microchipphy.h>
 #include <linux/phy.h>
+#include <linux/of_mdio.h>
 #include <linux/of_net.h>
 #include "lan78xx.h"
 
@@ -1760,6 +1761,7 @@ static int lan78xx_mdiobus_write(struct mii_bus *bus, int phy_id, int idx,
 
 static int lan78xx_mdio_init(struct lan78xx_net *dev)
 {
+	struct device_node *node;
 	int ret;
 
 	dev->mdiobus = mdiobus_alloc();
@@ -1788,7 +1790,13 @@ static int lan78xx_mdio_init(struct lan78xx_net *dev)
 		break;
 	}
 
-	ret = mdiobus_register(dev->mdiobus);
+	node = of_get_child_by_name(dev->udev->dev.of_node, "mdio");
+	if (node) {
+		ret = of_mdiobus_register(dev->mdiobus, node);
+		of_node_put(node);
+	} else {
+		ret = mdiobus_register(dev->mdiobus);
+	}
 	if (ret) {
 		netdev_err(dev->net, "can't register MDIO bus\n");
 		goto exit1;
@@ -2077,6 +2085,28 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
 	mii_adv = (u32)mii_advertise_flowctrl(dev->fc_request_control);
 	phydev->advertising |= mii_adv_to_ethtool_adv_t(mii_adv);
 
+	if (phydev->mdio.dev.of_node) {
+		u32 reg;
+		int len;
+
+		len = of_property_count_elems_of_size(phydev->mdio.dev.of_node,
+						      "microchip,led-modes",
+						      sizeof(u32));
+		if (len >= 0) {
+			/* Ensure the appropriate LEDs are enabled */
+			lan78xx_read_reg(dev, HW_CFG, &reg);
+			reg &= ~(HW_CFG_LED0_EN_ |
+				 HW_CFG_LED1_EN_ |
+				 HW_CFG_LED2_EN_ |
+				 HW_CFG_LED3_EN_);
+			reg |= (len > 0) * HW_CFG_LED0_EN_ |
+				(len > 1) * HW_CFG_LED1_EN_ |
+				(len > 2) * HW_CFG_LED2_EN_ |
+				(len > 3) * HW_CFG_LED3_EN_;
+			lan78xx_write_reg(dev, HW_CFG, reg);
+		}
+	}
+
 	genphy_config_aneg(phydev);
 
 	dev->fc_autoneg = phydev->autoneg;
diff --git a/include/dt-bindings/net/microchip-lan78xx.h b/include/dt-bindings/net/microchip-lan78xx.h
new file mode 100644
index 0000000..0742ff0
--- /dev/null
+++ b/include/dt-bindings/net/microchip-lan78xx.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _DT_BINDINGS_MICROCHIP_LAN78XX_H
+#define _DT_BINDINGS_MICROCHIP_LAN78XX_H
+
+/* LED modes for LAN7800/LAN7850 embedded PHY */
+
+#define LAN78XX_LINK_ACTIVITY           0
+#define LAN78XX_LINK_1000_ACTIVITY      1
+#define LAN78XX_LINK_100_ACTIVITY       2
+#define LAN78XX_LINK_10_ACTIVITY        3
+#define LAN78XX_LINK_100_1000_ACTIVITY  4
+#define LAN78XX_LINK_10_1000_ACTIVITY   5
+#define LAN78XX_LINK_10_100_ACTIVITY    6
+#define LAN78XX_DUPLEX_COLLISION        8
+#define LAN78XX_COLLISION               9
+#define LAN78XX_ACTIVITY                10
+#define LAN78XX_AUTONEG_FAULT           12
+#define LAN78XX_FORCE_LED_OFF           14
+#define LAN78XX_FORCE_LED_ON            15
+
+#endif
diff --git a/include/linux/microchipphy.h b/include/linux/microchipphy.h
index eb492d4..8e4015e 100644
--- a/include/linux/microchipphy.h
+++ b/include/linux/microchipphy.h
@@ -70,4 +70,7 @@
 #define	LAN88XX_MMD3_CHIP_ID			(32877)
 #define	LAN88XX_MMD3_CHIP_REV			(32878)
 
+/* Registers specific to the LAN7800/LAN7850 embedded phy */
+#define LAN78XX_PHY_LED_MODE_SELECT		(0x1D)
+
 #endif /* _MICROCHIPPHY_H */
-- 
2.7.4

[PATCH v3 3/3] dt-bindings: Document the DT bindings for lan78xx

[Phil Elwell]

The Microchip LAN78XX family of devices are Ethernet controllers with
a USB interface. Despite being discoverable devices it can be useful to
be able to configure them from Device Tree, particularly in low-cost
applications without an EEPROM or programmed OTP.

Document the supported properties in a bindings file.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 .../devicetree/bindings/net/microchip,lan78xx.txt  | 54 ++++++++++++++++++++++
 MAINTAINERS                                        |  1 +
 2 files changed, 55 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/microchip,lan78xx.txt

diff --git a/Documentation/devicetree/bindings/net/microchip,lan78xx.txt b/Documentation/devicetree/bindings/net/microchip,lan78xx.txt
new file mode 100644
index 0000000..a5d701b
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/microchip,lan78xx.txt
@@ -0,0 +1,54 @@
+Microchip LAN78xx Gigabit Ethernet controller
+
+The LAN78XX devices are usually configured by programming their OTP or with
+an external EEPROM, but some platforms (e.g. Raspberry Pi 3 B+) have neither.
+The Device Tree properties, if present, override the OTP and EEPROM.
+
+Required properties:
+- compatible: Should be one of "usb424,7800", "usb424,7801" or "usb424,7850".
+
+Optional properties:
+- local-mac-address:   see ethernet.txt
+- mac-address:         see ethernet.txt
+
+Optional properties of the embedded PHY:
+- microchip,led-modes: a 0..4 element vector, with each element configuring
+  the operating mode of an LED. Omitted LEDs are turned off. Allowed values
+  are defined in "include/dt-bindings/net/microchip-lan78xx.h".
+
+Example:
+
+/* Based on the configuration for a Raspberry Pi 3 B+ */
+&usb {
+	usb1@1 {
+		compatible = "usb424,2514";
+		reg = <1>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		usb1_1@1 {
+			compatible = "usb424,2514";
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			ethernet: usbether@1 {
+				compatible = "usb424,7800";
+				reg = <1>;
+				local-mac-address = [ 00 11 22 33 44 55 ];
+
+				mdio {
+					#address-cells = <0x1>;
+					#size-cells = <0x0>;
+					eth_phy: ethernet-phy@1 {
+						reg = <1>;
+						microchip,led-modes = <
+						 	LAN78XX_LINK_1000_ACTIVITY
+							LAN78XX_LINK_10_100_ACTIVITY
+						>;
+					};
+				};
+			};
+		};
+	};
+};
diff --git a/MAINTAINERS b/MAINTAINERS
index 23735d9..91cb961 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14572,6 +14572,7 @@ M:	Woojung Huh <woojung.huh@microchip.com>
 M:	Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>
 L:	netdev@vger.kernel.org
 S:	Maintained
+F:	Documentation/devicetree/bindings/net/microchip,lan78xx.txt
 F:	drivers/net/usb/lan78xx.*
 F:	include/dt-bindings/net/microchip-lan78xx.h
 
-- 
2.7.4

Re: [PATCH v3 2/3] lan78xx: Read LED states from Device Tree

[Andrew Lunn]

> @@ -2077,6 +2085,28 @@ static int lan78xx_phy_init(struct lan78xx_net *dev)
>  	mii_adv = (u32)mii_advertise_flowctrl(dev->fc_request_control);
>  	phydev->advertising |= mii_adv_to_ethtool_adv_t(mii_adv);
>  
> +	if (phydev->mdio.dev.of_node) {
> +		u32 reg;
> +		int len;
> +
> +		len = of_property_count_elems_of_size(phydev->mdio.dev.of_node,
> +						      "microchip,led-modes",
> +						      sizeof(u32));
> +		if (len >= 0) {
> +			/* Ensure the appropriate LEDs are enabled */
> +			lan78xx_read_reg(dev, HW_CFG, &reg);
> +			reg &= ~(HW_CFG_LED0_EN_ |
> +				 HW_CFG_LED1_EN_ |
> +				 HW_CFG_LED2_EN_ |
> +				 HW_CFG_LED3_EN_);
> +			reg |= (len > 0) * HW_CFG_LED0_EN_ |
> +				(len > 1) * HW_CFG_LED1_EN_ |
> +				(len > 2) * HW_CFG_LED2_EN_ |
> +				(len > 3) * HW_CFG_LED3_EN_;
> +			lan78xx_write_reg(dev, HW_CFG, reg);
> +		}
> +	}
> +

Humm. Not nice. But i cannot think of a cleaner way of doing this.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew

Re: [PATCH v3 3/3] dt-bindings: Document the DT bindings for lan78xx

[Andrew Lunn]

On Thu, Apr 19, 2018 at 03:32:05PM +0100, Phil Elwell wrote:
> The Microchip LAN78XX family of devices are Ethernet controllers with
> a USB interface. Despite being discoverable devices it can be useful to
> be able to configure them from Device Tree, particularly in low-cost
> applications without an EEPROM or programmed OTP.
> 
> Document the supported properties in a bindings file.
> 
> Signed-off-by: Phil Elwell <phil@raspberrypi.org>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew