dm: net: Tidy up designware driver ready for driver model

Adjust the error handling to use errno.h instead of returning -1. Change
leaf functions to pass in the arguments they require rather than struct
eth_device. Apart from simplifying the code it makes is easier to reuse
these functions for driver model, since mostly they actually only use
struct dw_eth_priv (which we can keep).

Create a stub for each Ethernet operation function. This will allow use to
share code with the driver model versions.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>

drivers/net/designware.c

@@ -6,10 +6,11 @@
  */
 
 /*
- * Designware ethernet IP driver for u-boot
+ * Designware ethernet IP driver for U-Boot
  */
 
 #include <common.h>
+#include <errno.h>
 #include <miiphy.h>
 #include <malloc.h>
 #include <linux/compiler.h>
@@ -40,7 +41,7 @@ static int dw_mdio_read(struct mii_dev *bus, int addr, int devad, int reg)
 		udelay(10);
 	};
 
-	return -1;
+	return -ETIMEDOUT;
 }
 
 static int dw_mdio_write(struct mii_dev *bus, int addr, int devad, int reg,
@@ -49,7 +50,7 @@ static int dw_mdio_write(struct mii_dev *bus, int addr, int devad, int reg,
 	struct eth_mac_regs *mac_p = bus->priv;
 	ulong start;
 	u16 miiaddr;
-	int ret = -1, timeout = CONFIG_MDIO_TIMEOUT;
+	int ret = -ETIMEDOUT, timeout = CONFIG_MDIO_TIMEOUT;
 
 	writel(val, &mac_p->miidata);
 	miiaddr = ((addr << MIIADDRSHIFT) & MII_ADDRMSK) |
@@ -69,27 +70,26 @@ static int dw_mdio_write(struct mii_dev *bus, int addr, int devad, int reg,
 	return ret;
 }
 
-static int dw_mdio_init(char *name, struct eth_mac_regs *mac_regs_p)
+static int dw_mdio_init(const char *name, struct eth_mac_regs *mac_regs_p)
 {
 	struct mii_dev *bus = mdio_alloc();
 
 	if (!bus) {
 		printf("Failed to allocate MDIO bus\n");
-		return -1;
+		return -ENOMEM;
 	}
 
 	bus->read = dw_mdio_read;
 	bus->write = dw_mdio_write;
-	sprintf(bus->name, name);
+	snprintf(bus->name, sizeof(bus->name), name);
 
 	bus->priv = (void *)mac_regs_p;
 
 	return mdio_register(bus);
 }
 
-static void tx_descs_init(struct eth_device *dev)
+static void tx_descs_init(struct dw_eth_dev *priv)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	struct eth_dma_regs *dma_p = priv->dma_regs_p;
 	struct dmamacdescr *desc_table_p = &priv->tx_mac_descrtable[0];
 	char *txbuffs = &priv->txbuffs[0];
@@ -128,9 +128,8 @@ static void tx_descs_init(struct eth_device *dev)
 	priv->tx_currdescnum = 0;
 }
 
-static void rx_descs_init(struct eth_device *dev)
+static void rx_descs_init(struct dw_eth_dev *priv)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	struct eth_dma_regs *dma_p = priv->dma_regs_p;
 	struct dmamacdescr *desc_table_p = &priv->rx_mac_descrtable[0];
 	char *rxbuffs = &priv->rxbuffs[0];
@@ -170,12 +169,10 @@ static void rx_descs_init(struct eth_device *dev)
 	priv->rx_currdescnum = 0;
 }
 
-static int dw_write_hwaddr(struct eth_device *dev)
+static int _dw_write_hwaddr(struct dw_eth_dev *priv, u8 *mac_id)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	struct eth_mac_regs *mac_p = priv->mac_regs_p;
 	u32 macid_lo, macid_hi;
-	u8 *mac_id = &dev->enetaddr[0];
 
 	macid_lo = mac_id[0] + (mac_id[1] << 8) + (mac_id[2] << 16) +
 		   (mac_id[3] << 24);
@@ -213,9 +210,8 @@ static void dw_adjust_link(struct eth_mac_regs *mac_p,
 	       (phydev->port == PORT_FIBRE) ? ", fiber mode" : "");
 }
 
-static void dw_eth_halt(struct eth_device *dev)
+static void _dw_eth_halt(struct dw_eth_dev *priv)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	struct eth_mac_regs *mac_p = priv->mac_regs_p;
 	struct eth_dma_regs *dma_p = priv->dma_regs_p;
 
@@ -225,12 +221,12 @@ static void dw_eth_halt(struct eth_device *dev)
 	phy_shutdown(priv->phydev);
 }
 
-static int dw_eth_init(struct eth_device *dev, bd_t *bis)
+static int _dw_eth_init(struct dw_eth_dev *priv, u8 *enetaddr)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	struct eth_mac_regs *mac_p = priv->mac_regs_p;
 	struct eth_dma_regs *dma_p = priv->dma_regs_p;
 	unsigned int start;
+	int ret;
 
 	writel(readl(&dma_p->busmode) | DMAMAC_SRST, &dma_p->busmode);
 
@@ -238,7 +234,7 @@ static int dw_eth_init(struct eth_device *dev, bd_t *bis)
 	while (readl(&dma_p->busmode) & DMAMAC_SRST) {
 		if (get_timer(start) >= CONFIG_MACRESET_TIMEOUT) {
 			printf("DMA reset timeout\n");
-			return -1;
+			return -ETIMEDOUT;
 		}
 
 		mdelay(100);
@@ -246,10 +242,10 @@ static int dw_eth_init(struct eth_device *dev, bd_t *bis)
 
 	/* Soft reset above clears HW address registers.
 	 * So we have to set it here once again */
-	dw_write_hwaddr(dev);
+	_dw_write_hwaddr(priv, enetaddr);
 
-	rx_descs_init(dev);
-	tx_descs_init(dev);
+	rx_descs_init(priv);
+	tx_descs_init(priv);
 
 	writel(FIXEDBURST | PRIORXTX_41 | DMA_PBL, &dma_p->busmode);
 
@@ -268,25 +264,25 @@ static int dw_eth_init(struct eth_device *dev, bd_t *bis)
 #endif
 
 	/* Start up the PHY */
-	if (phy_startup(priv->phydev)) {
+	ret = phy_startup(priv->phydev);
+	if (ret) {
 		printf("Could not initialize PHY %s\n",
 		       priv->phydev->dev->name);
-		return -1;
+		return ret;
 	}
 
 	dw_adjust_link(mac_p, priv->phydev);
 
 	if (!priv->phydev->link)
-		return -1;
+		return -EIO;
 
 	writel(readl(&mac_p->conf) | RXENABLE | TXENABLE, &mac_p->conf);
 
 	return 0;
 }
 
-static int dw_eth_send(struct eth_device *dev, void *packet, int length)
+static int _dw_eth_send(struct dw_eth_dev *priv, void *packet, int length)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	struct eth_dma_regs *dma_p = priv->dma_regs_p;
 	u32 desc_num = priv->tx_currdescnum;
 	struct dmamacdescr *desc_p = &priv->tx_mac_descrtable[desc_num];
@@ -309,7 +305,7 @@ static int dw_eth_send(struct eth_device *dev, void *packet, int length)
 	/* Check if the descriptor is owned by CPU */
 	if (desc_p->txrx_status & DESC_TXSTS_OWNBYDMA) {
 		printf("CPU not owner of tx frame\n");
-		return -1;
+		return -EPERM;
 	}
 
 	memcpy(desc_p->dmamac_addr, packet, length);
@@ -347,9 +343,8 @@ static int dw_eth_send(struct eth_device *dev, void *packet, int length)
 	return 0;
 }
 
-static int dw_eth_recv(struct eth_device *dev)
+static int _dw_eth_recv(struct dw_eth_dev *priv)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	u32 status, desc_num = priv->rx_currdescnum;
 	struct dmamacdescr *desc_p = &priv->rx_mac_descrtable[desc_num];
 	int length = 0;
@@ -395,9 +390,8 @@ static int dw_eth_recv(struct eth_device *dev)
 	return length;
 }
 
-static int dw_phy_init(struct eth_device *dev)
+static int dw_phy_init(struct dw_eth_dev *priv, void *dev)
 {
-	struct dw_eth_dev *priv = dev->priv;
 	struct phy_device *phydev;
 	int mask = 0xffffffff;
 
@@ -407,7 +401,7 @@ static int dw_phy_init(struct eth_device *dev)
 
 	phydev = phy_find_by_mask(priv->bus, mask, priv->interface);
 	if (!phydev)
-		return -1;
+		return -ENODEV;
 
 	phy_connect_dev(phydev, dev);
 
@@ -417,7 +411,32 @@ static int dw_phy_init(struct eth_device *dev)
 	priv->phydev = phydev;
 	phy_config(phydev);
 
-	return 1;
+	return 0;
+}
+
+static int dw_eth_init(struct eth_device *dev, bd_t *bis)
+{
+	return _dw_eth_init(dev->priv, dev->enetaddr);
+}
+
+static int dw_eth_send(struct eth_device *dev, void *packet, int length)
+{
+	return _dw_eth_send(dev->priv, packet, length);
+}
+
+static int dw_eth_recv(struct eth_device *dev)
+{
+	return _dw_eth_recv(dev->priv);
+}
+
+static void dw_eth_halt(struct eth_device *dev)
+{
+	return _dw_eth_halt(dev->priv);
+}
+
+static int dw_write_hwaddr(struct eth_device *dev)
+{
+	return _dw_write_hwaddr(dev->priv, dev->enetaddr);
 }
 
 int designware_initialize(ulong base_addr, u32 interface)
@@ -465,5 +484,5 @@ int designware_initialize(ulong base_addr, u32 interface)
 	dw_mdio_init(dev->name, priv->mac_regs_p);
 	priv->bus = miiphy_get_dev_by_name(dev->name);
 
-	return dw_phy_init(dev);
+	return dw_phy_init(priv, dev);
 }