[NET] smc91x: prepare for SMC_IO_SHIFT to be a platform configurable variable

Now one can use the following code

  #define SMC_IO_SHIFT	lp->io_shift

to make SMC_IO_SHIFT a variable. This, however, will slightly increase
the CPU overhead and have negative impact on the network performance.
The tradeoff is, this can be specified in the smc91x platform data so
that multiple boards support can be built in a single zImage.

Signed-off-by: Eric Miao <eric.miao@marvell.com>
Acked-by: Nicolas Pitre <nico@cam.org>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/net/smc91x.c

@@ -2050,9 +2050,11 @@ static int smc_enable_device(struct platform_device *pdev)
 	return 0;
 }
 
-static int smc_request_attrib(struct platform_device *pdev)
+static int smc_request_attrib(struct platform_device *pdev,
+			      struct net_device *ndev)
 {
 	struct resource * res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-attrib");
+	struct smc_local *lp = netdev_priv(ndev);
 
 	if (!res)
 		return 0;
@@ -2063,9 +2065,11 @@ static int smc_request_attrib(struct platform_device *pdev)
 	return 0;
 }
 
-static void smc_release_attrib(struct platform_device *pdev)
+static void smc_release_attrib(struct platform_device *pdev,
+			       struct net_device *ndev)
 {
 	struct resource * res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-attrib");
+	struct smc_local *lp = netdev_priv(ndev);
 
 	if (res)
 		release_mem_region(res->start, ATTRIB_SIZE);
@@ -2126,25 +2130,11 @@ static int smc_drv_probe(struct platform_device *pdev)
 	unsigned long irq_flags = SMC_IRQ_FLAGS;
 	int ret;
 
-	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-regs");
-	if (!res)
-		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		ret = -ENODEV;
-		goto out;
-	}
-
-
-	if (!request_mem_region(res->start, SMC_IO_EXTENT, CARDNAME)) {
-		ret = -EBUSY;
-		goto out;
-	}
-
 	ndev = alloc_etherdev(sizeof(struct smc_local));
 	if (!ndev) {
 		printk("%s: could not allocate device.\n", CARDNAME);
 		ret = -ENOMEM;
-		goto out_release_io;
+		goto out;
 	}
 	SET_NETDEV_DEV(ndev, &pdev->dev);
 
@@ -2154,9 +2144,10 @@ static int smc_drv_probe(struct platform_device *pdev)
 
 	lp = netdev_priv(ndev);
 
-	if (pd)
+	if (pd) {
 		memcpy(&lp->cfg, pd, sizeof(lp->cfg));
-	else {
+		lp->io_shift = SMC91X_IO_SHIFT(lp->cfg.flags);
+	} else {
 		lp->cfg.flags |= (SMC_CAN_USE_8BIT)  ? SMC91X_USE_8BIT  : 0;
 		lp->cfg.flags |= (SMC_CAN_USE_16BIT) ? SMC91X_USE_16BIT : 0;
 		lp->cfg.flags |= (SMC_CAN_USE_32BIT) ? SMC91X_USE_32BIT : 0;
@@ -2165,10 +2156,24 @@ static int smc_drv_probe(struct platform_device *pdev)
 
 	ndev->dma = (unsigned char)-1;
 
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-regs");
+	if (!res)
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		ret = -ENODEV;
+		goto out_free_netdev;
+	}
+
+
+	if (!request_mem_region(res->start, SMC_IO_EXTENT, CARDNAME)) {
+		ret = -EBUSY;
+		goto out_free_netdev;
+	}
+
 	ires = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!ires) {
 		ret = -ENODEV;
-		goto out_free_netdev;
+		goto out_release_io;
 	}
 
 	ndev->irq = ires->start;
@@ -2176,9 +2181,9 @@ static int smc_drv_probe(struct platform_device *pdev)
 	if (ires->flags & IRQF_TRIGGER_MASK)
 		irq_flags = ires->flags & IRQF_TRIGGER_MASK;
 
-	ret = smc_request_attrib(pdev);
+	ret = smc_request_attrib(pdev, ndev);
 	if (ret)
-		goto out_free_netdev;
+		goto out_release_io;
 #if defined(CONFIG_SA1100_ASSABET)
 	NCR_0 |= NCR_ENET_OSC_EN;
 #endif
@@ -2213,11 +2218,11 @@ static int smc_drv_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, NULL);
 	iounmap(addr);
  out_release_attrib:
-	smc_release_attrib(pdev);
- out_free_netdev:
-	free_netdev(ndev);
+	smc_release_attrib(pdev, ndev);
  out_release_io:
 	release_mem_region(res->start, SMC_IO_EXTENT);
+ out_free_netdev:
+	free_netdev(ndev);
  out:
 	printk("%s: not found (%d).\n", CARDNAME, ret);
 
@@ -2243,7 +2248,7 @@ static int smc_drv_remove(struct platform_device *pdev)
 	iounmap(lp->base);
 
 	smc_release_datacs(pdev,ndev);
-	smc_release_attrib(pdev);
+	smc_release_attrib(pdev,ndev);
 
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "smc91x-regs");
 	if (!res)

drivers/net/smc91x.h

@@ -500,6 +500,9 @@ struct smc_local {
 	void __iomem *base;
 	void __iomem *datacs;
 
+	/* the low address lines on some platforms aren't connected... */
+	int	io_shift;
+
 	struct smc91x_platdata cfg;
 };
 

include/linux/smc91x.h

@@ -7,6 +7,13 @@
 
 #define SMC91X_NOWAIT		(1 << 3)
 
+/* two bits for IO_SHIFT, let's hope later designs will keep this sane */
+#define SMC91X_IO_SHIFT_0	(0 << 4)
+#define SMC91X_IO_SHIFT_1	(1 << 4)
+#define SMC91X_IO_SHIFT_2	(2 << 4)
+#define SMC91X_IO_SHIFT_3	(3 << 4)
+#define SMC91X_IO_SHIFT(x)	(((x) >> 4) & 0x3)
+
 struct smc91x_platdata {
 	unsigned long flags;
 };