[RFC PATCH] net: dm9000: add support for device tree probing

[Daniel Morsing]

This patch adds support for probing the dm9000 driver through device
trees.

The patch works by supplying its own platform_data struct when probed
via device tree. This allows us to rely on the existing options parsing
in the driver and avoid ifdeffery in the probe function.

Signed-off-by: Daniel Morsing <daniel.morsing at gmail.com>
---
 Documentation/devicetree/bindings/net/dm9000.txt |   46 ++++++++++++
 drivers/net/dm9000.c                             |   85 ++++++++++++++++++++++
 2 files changed, 131 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/dm9000.txt

diff --git a/Documentation/devicetree/bindings/net/dm9000.txt b/Documentation/devicetree/bindings/net/dm9000.txt
new file mode 100644
index 0000000..f13ce20
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/dm9000.txt
@@ -0,0 +1,46 @@
+Davicom DM9000 ethernet controller
+
+Required properties:
+
+ - compatible : Should be "davicom,dm9000"
+
+ - interrupts : Interrupt controller specific encoding, which specifies 1
+   or 2 interrupts. The first interrupt is for rx/tx received and is required
+   by the driver to function. The second interrupt is for wake on lan support
+   and is optional.
+
+ - interrupt-flags : A one cell value which specifies the flag values for
+   the first interrupt, corresponding to the IORESOURCE_IRQ_* flags. An
+   example is using the value <8> for specifying the IORESOURCE_IRQ_LOWLEVEL
+   flag
+
+ - reg : 2 Physical address specifiers, where the first specifies the address
+   register of device, and the second specifies the data register of the device
+
+Optional properties:
+
+ - local-mac-address : Binary data specifying a mac address override
+
+ - The following properties are all empty properties and specify one of the
+   flags that can be passed with the platform data to the driver. For specifics
+   about what the flags mean, see Documentation/networking/dm9000.txt
+
+   8bitonly:	DM9000_PLATF_8BITONLY
+   16bitonly:	DM9000_PLATF_16BITONLY
+   32bitonly:	DM9000_PLATF_32BITONLY
+   ext-phy:	DM9000_PLATF_EXT_PHY
+   no-eeprom:	DM9000_PLATF_NO_EEPROM
+   simple-phy:	DM9000_PLATF_SIMPLE_PHY
+
+Example:
+
+ethernet0 at 2c000000 {
+	compatible = "davicom,dm9000";
+	reg = <0x2c000000 0x04>,
+	      <0x2c000400 0x04>;
+	interrupts = <185>;
+	interrupt-flags = <8>; /* IORESOURCE_IRQ_LOWLEVEL */
+	local-mac-address = [02 65 16 01 c0 09];
+	16bitonly;
+	no-eeprom;
+};
diff --git a/drivers/net/dm9000.c b/drivers/net/dm9000.c
index 8ef31dc..4ad5043 100644
--- a/drivers/net/dm9000.c
+++ b/drivers/net/dm9000.c
@@ -35,6 +35,7 @@
 #include <linux/platform_device.h>
 #include <linux/irq.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 #include <asm/delay.h>
 #include <asm/irq.h>
@@ -1350,6 +1351,77 @@ static const struct net_device_ops dm9000_netdev_ops = {
 #endif
 };
 
+#ifdef CONFIG_OF
+static const struct of_device_id dm9000_of_match[] = {
+	{ .compatible = "davicom,dm9000" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, dm9000_of_match);
+
+static const struct {
+	const char *property;
+	unsigned int flag;
+} property_lookup[] __devinitconst = {
+	{ "8bitonly", DM9000_PLATF_8BITONLY},
+	{ "16bitonly", DM9000_PLATF_16BITONLY},
+	{ "32bitonly", DM9000_PLATF_32BITONLY},
+	{ "ext-phy", DM9000_PLATF_EXT_PHY},
+	{ "no-eeprom", DM9000_PLATF_NO_EEPROM},
+	{ "simple-phy", DM9000_PLATF_SIMPLE_PHY},
+	{},
+};
+
+static int __devinit
+dm9000_dt_fill_platdata(struct platform_device *pdev,
+			struct dm9000_plat_data *pdata)
+{
+	struct resource *irq_res;
+	struct device_node *of_node = pdev->dev.of_node;
+	const u8 *mac_addr;
+
+	u32 intflags;
+	int i;
+
+	if (of_property_read_u32(of_node, "interrupt-flags", &intflags)) {
+		dev_err(&pdev->dev,
+			"interrupt-flags property not found in device tree\n");
+		return -EINVAL;
+	}
+
+	irq_res  = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!irq_res) {
+		dev_err(&pdev->dev, "No irq found in device tree\n");
+		return -EINVAL;
+	}
+	irq_res->flags |= intflags;
+
+	for (i = 0; property_lookup[i].property; i++) {
+		struct property *prop;
+		prop = of_find_property(of_node, property_lookup[i].property,
+					NULL);
+		if (prop) {
+			pdata->flags |= property_lookup[i].flag;
+			dev_dbg(&pdev->dev, "%s property found in device tree\n",
+					property_lookup[i].property);
+		}
+	}
+
+	mac_addr = of_get_property(of_node, "local-mac-address", NULL);
+	if (mac_addr)
+		memcpy(pdata->dev_addr, mac_addr, 6);
+
+	return 0;
+}
+
+#else
+#define dm9000_of_match NULL
+static inline int dm9000_dt_fill_platdata(struct platform_device *pdev,
+					   struct dm9000_plat_data *pdata)
+{
+	return 0;
+}
+#endif /* CONFIG_OF */
+
 /*
  * Search DM9000 board, allocate space and register it
  */
@@ -1359,12 +1431,24 @@ dm9000_probe(struct platform_device *pdev)
 	struct dm9000_plat_data *pdata = pdev->dev.platform_data;
 	struct board_info *db;	/* Point a board information structure */
 	struct net_device *ndev;
+	struct dm9000_plat_data pdata_of;
 	const unsigned char *mac_src;
 	int ret = 0;
 	int iosize;
 	int i;
 	u32 id_val;
 
+	if (pdev->dev.of_node) {
+		if (!pdata) {
+			memset(&pdata_of, 0, sizeof(pdata_of));
+			pdata = &pdata_of;
+		}
+
+		ret = dm9000_dt_fill_platdata(pdev, pdata);
+		if (ret < 0)
+			return ret;
+	}
+
 	/* Init network device */
 	ndev = alloc_etherdev(sizeof(struct board_info));
 	if (!ndev) {
@@ -1677,6 +1761,7 @@ static struct platform_driver dm9000_driver = {
 		.name    = "dm9000",
 		.owner	 = THIS_MODULE,
 		.pm	 = &dm9000_drv_pm_ops,
+		.of_match_table = dm9000_of_match,
 	},
 	.probe   = dm9000_probe,
 	.remove  = __devexit_p(dm9000_drv_remove),
-- 
1.7.6