phy: move fixed_phy MII register generation to a library

Move the fixed_phy MII register generation to a library to allow other
software phy implementations to use this code.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/Kconfig

@@ -12,6 +12,9 @@ menuconfig PHYLIB
 
 if PHYLIB
 
+config SWPHY
+	bool
+
 comment "MII PHY device drivers"
 
 config AQUANTIA_PHY
@@ -159,6 +162,7 @@ config MICROCHIP_PHY
 config FIXED_PHY
 	tristate "Driver for MDIO Bus/PHY emulation with fixed speed/link PHYs"
 	depends on PHYLIB
+	select SWPHY
 	---help---
 	  Adds the platform "fixed" MDIO Bus to cover the boards that use
 	  PHYs that are not connected to the real MDIO bus.

drivers/net/phy/Makefile

@@ -1,6 +1,7 @@
 # Makefile for Linux PHY drivers
 
-libphy-objs			:= phy.o phy_device.o mdio_bus.o mdio_device.o
+libphy-y			:= phy.o phy_device.o mdio_bus.o mdio_device.o
+libphy-$(CONFIG_SWPHY)		+= swphy.o
 
 obj-$(CONFIG_PHYLIB)		+= libphy.o
 obj-$(CONFIG_AQUANTIA_PHY)	+= aquantia.o

drivers/net/phy/fixed_phy.c

@@ -24,6 +24,8 @@
 #include <linux/of.h>
 #include <linux/gpio.h>
 
+#include "swphy.h"
+
 #define MII_REGS_NUM 29
 
 struct fixed_mdio_bus {
@@ -48,101 +50,10 @@ static struct fixed_mdio_bus platform_fmb = {
 
 static int fixed_phy_update_regs(struct fixed_phy *fp)
 {
-	u16 bmsr = BMSR_ANEGCAPABLE;
-	u16 bmcr = 0;
-	u16 lpagb = 0;
-	u16 lpa = 0;
-
 	if (gpio_is_valid(fp->link_gpio))
 		fp->status.link = !!gpio_get_value_cansleep(fp->link_gpio);
 
-	if (fp->status.duplex) {
-		switch (fp->status.speed) {
-		case 1000:
-			bmsr |= BMSR_ESTATEN;
-			break;
-		case 100:
-			bmsr |= BMSR_100FULL;
-			break;
-		case 10:
-			bmsr |= BMSR_10FULL;
-			break;
-		default:
-			break;
-		}
-	} else {
-		switch (fp->status.speed) {
-		case 1000:
-			bmsr |= BMSR_ESTATEN;
-			break;
-		case 100:
-			bmsr |= BMSR_100HALF;
-			break;
-		case 10:
-			bmsr |= BMSR_10HALF;
-			break;
-		default:
-			break;
-		}
-	}
-
-	if (fp->status.link) {
-		bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE;
-
-		if (fp->status.duplex) {
-			bmcr |= BMCR_FULLDPLX;
-
-			switch (fp->status.speed) {
-			case 1000:
-				bmcr |= BMCR_SPEED1000;
-				lpagb |= LPA_1000FULL;
-				break;
-			case 100:
-				bmcr |= BMCR_SPEED100;
-				lpa |= LPA_100FULL;
-				break;
-			case 10:
-				lpa |= LPA_10FULL;
-				break;
-			default:
-				pr_warn("fixed phy: unknown speed\n");
-				return -EINVAL;
-			}
-		} else {
-			switch (fp->status.speed) {
-			case 1000:
-				bmcr |= BMCR_SPEED1000;
-				lpagb |= LPA_1000HALF;
-				break;
-			case 100:
-				bmcr |= BMCR_SPEED100;
-				lpa |= LPA_100HALF;
-				break;
-			case 10:
-				lpa |= LPA_10HALF;
-				break;
-			default:
-				pr_warn("fixed phy: unknown speed\n");
-			return -EINVAL;
-			}
-		}
-
-		if (fp->status.pause)
-			lpa |= LPA_PAUSE_CAP;
-
-		if (fp->status.asym_pause)
-			lpa |= LPA_PAUSE_ASYM;
-	}
-
-	fp->regs[MII_PHYSID1] = 0;
-	fp->regs[MII_PHYSID2] = 0;
-
-	fp->regs[MII_BMSR] = bmsr;
-	fp->regs[MII_BMCR] = bmcr;
-	fp->regs[MII_LPA] = lpa;
-	fp->regs[MII_STAT1000] = lpagb;
-
-	return 0;
+	return swphy_update_regs(fp->regs, &fp->status);
 }
 
 static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num)

drivers/net/phy/swphy.c

@@ -0,0 +1,126 @@
+/*
+ * Software PHY emulation
+ *
+ * Code taken from fixed_phy.c by Russell King <rmk+kernel@arm.linux.org.uk>
+ *
+ * Author: Vitaly Bordug <vbordug@ru.mvista.com>
+ *         Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * Copyright (c) 2006-2007 MontaVista Software, Inc.
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+#include <linux/export.h>
+#include <linux/mii.h>
+#include <linux/phy.h>
+#include <linux/phy_fixed.h>
+
+#include "swphy.h"
+
+/**
+ * swphy_update_regs - update MII register array with fixed phy state
+ * @regs: array of 32 registers to update
+ * @state: fixed phy status
+ *
+ * Update the array of MII registers with the fixed phy link, speed,
+ * duplex and pause mode settings.
+ */
+int swphy_update_regs(u16 *regs, const struct fixed_phy_status *state)
+{
+	u16 bmsr = BMSR_ANEGCAPABLE;
+	u16 bmcr = 0;
+	u16 lpagb = 0;
+	u16 lpa = 0;
+
+	if (state->duplex) {
+		switch (state->speed) {
+		case 1000:
+			bmsr |= BMSR_ESTATEN;
+			break;
+		case 100:
+			bmsr |= BMSR_100FULL;
+			break;
+		case 10:
+			bmsr |= BMSR_10FULL;
+			break;
+		default:
+			break;
+		}
+	} else {
+		switch (state->speed) {
+		case 1000:
+			bmsr |= BMSR_ESTATEN;
+			break;
+		case 100:
+			bmsr |= BMSR_100HALF;
+			break;
+		case 10:
+			bmsr |= BMSR_10HALF;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (state->link) {
+		bmsr |= BMSR_LSTATUS | BMSR_ANEGCOMPLETE;
+
+		if (state->duplex) {
+			bmcr |= BMCR_FULLDPLX;
+
+			switch (state->speed) {
+			case 1000:
+				bmcr |= BMCR_SPEED1000;
+				lpagb |= LPA_1000FULL;
+				break;
+			case 100:
+				bmcr |= BMCR_SPEED100;
+				lpa |= LPA_100FULL;
+				break;
+			case 10:
+				lpa |= LPA_10FULL;
+				break;
+			default:
+				pr_warn("swphy: unknown speed\n");
+				return -EINVAL;
+			}
+		} else {
+			switch (state->speed) {
+			case 1000:
+				bmcr |= BMCR_SPEED1000;
+				lpagb |= LPA_1000HALF;
+				break;
+			case 100:
+				bmcr |= BMCR_SPEED100;
+				lpa |= LPA_100HALF;
+				break;
+			case 10:
+				lpa |= LPA_10HALF;
+				break;
+			default:
+				pr_warn("swphy: unknown speed\n");
+				return -EINVAL;
+			}
+		}
+
+		if (state->pause)
+			lpa |= LPA_PAUSE_CAP;
+
+		if (state->asym_pause)
+			lpa |= LPA_PAUSE_ASYM;
+	}
+
+	regs[MII_PHYSID1] = 0;
+	regs[MII_PHYSID2] = 0;
+
+	regs[MII_BMSR] = bmsr;
+	regs[MII_BMCR] = bmcr;
+	regs[MII_LPA] = lpa;
+	regs[MII_STAT1000] = lpagb;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(swphy_update_regs);

drivers/net/phy/swphy.h

@@ -0,0 +1,8 @@
+#ifndef SWPHY_H
+#define SWPHY_H
+
+struct fixed_phy_status;
+
+int swphy_update_regs(u16 *regs, const struct fixed_phy_status *state);
+
+#endif