USB: Davicom DM9601 usbnet driver

This patch adds a driver for the Davicom DM9601 USB 1.1 10/100Mbps
ethernet adaptor using the usbnet framework.

See http://www.davicom.com.tw/eng/products/dm9601.htm for details.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

4 files changed, 623 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index c268b51..a9c1319 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3392,6 +3392,13 @@ L:	linux-usb-devel@lists.sourceforge.net
 S:	Maintained
 W:	http://www.kroah.com/linux-usb/
 
+USB DAVICOM DM9601 DRIVER
+P:	Peter Korsgaard
+M:	jacmet@sunsite.dk
+L:	linux-usb-devel@lists.sourceforge.net
+W:	http://www.linux-usb.org/usbnet
+S:	Maintained
+
 USB EHCI DRIVER
 P:	David Brownell
 M:	dbrownell@users.sourceforge.net
diff --git a/drivers/usb/net/Kconfig b/drivers/usb/net/Kconfig
index 0f3d7db..3de564b 100644
--- a/drivers/usb/net/Kconfig
+++ b/drivers/usb/net/Kconfig
@@ -186,6 +186,15 @@ config USB_NET_CDCETHER
 	  IEEE 802 "local assignment" bit is set in the address, a "usbX"
 	  name is used instead.
 
+config USB_NET_DM9601
+	tristate "Davicom DM9601 based USB 1.1 10/100 ethernet devices"
+	depends on USB_USBNET
+	select CRC32
+	select USB_USBNET_MII
+	help
+	  This option adds support for Davicom DM9601 based USB 1.1
+	  10/100 Ethernet adapters.
+
 config USB_NET_GL620A
 	tristate "GeneSys GL620USB-A based cables"
 	depends on USB_USBNET
diff --git a/drivers/usb/net/Makefile b/drivers/usb/net/Makefile
index 7b51964..595a539 100644
--- a/drivers/usb/net/Makefile
+++ b/drivers/usb/net/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_USB_PEGASUS)	+= pegasus.o
 obj-$(CONFIG_USB_RTL8150)	+= rtl8150.o
 obj-$(CONFIG_USB_NET_AX8817X)	+= asix.o
 obj-$(CONFIG_USB_NET_CDCETHER)	+= cdc_ether.o
+obj-$(CONFIG_USB_NET_DM9601)	+= dm9601.o
 obj-$(CONFIG_USB_NET_GL620A)	+= gl620a.o
 obj-$(CONFIG_USB_NET_NET1080)	+= net1080.o
 obj-$(CONFIG_USB_NET_PLUSB)	+= plusb.o
diff --git a/drivers/usb/net/dm9601.c b/drivers/usb/net/dm9601.c
new file mode 100644
index 0000000..4a932e1
--- /dev/null
+++ b/drivers/usb/net/dm9601.c
@@ -0,0 +1,606 @@
+/*
+ * Davicom DM9601 USB 1.1 10/100Mbps ethernet devices
+ *
+ * Peter Korsgaard <jacmet@sunsite.dk>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2.  This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+//#define DEBUG
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/mii.h>
+#include <linux/usb.h>
+#include <linux/crc32.h>
+
+#include "usbnet.h"
+
+/* datasheet:
+ http://www.davicom.com.tw/big5/download/Data%20Sheet/DM9601-DS-P01-930914.pdf
+*/
+
+/* control requests */
+#define DM_READ_REGS	0x00
+#define DM_WRITE_REGS	0x01
+#define DM_READ_MEMS	0x02
+#define DM_WRITE_REG	0x03
+#define DM_WRITE_MEMS	0x05
+#define DM_WRITE_MEM	0x07
+
+/* registers */
+#define DM_NET_CTRL	0x00
+#define DM_RX_CTRL	0x05
+#define DM_SHARED_CTRL	0x0b
+#define DM_SHARED_ADDR	0x0c
+#define DM_SHARED_DATA	0x0d	/* low + high */
+#define DM_PHY_ADDR	0x10	/* 6 bytes */
+#define DM_MCAST_ADDR	0x16	/* 8 bytes */
+#define DM_GPR_CTRL	0x1e
+#define DM_GPR_DATA	0x1f
+
+#define DM_MAX_MCAST	64
+#define DM_MCAST_SIZE	8
+#define DM_EEPROM_LEN	256
+#define DM_TX_OVERHEAD	2	/* 2 byte header */
+#define DM_RX_OVERHEAD	7	/* 3 byte header + 4 byte crc tail */
+#define DM_TIMEOUT	1000
+
+
+static int dm_read(struct usbnet *dev, u8 reg, u16 length, void *data)
+{
+	devdbg(dev, "dm_read() reg=0x%02x length=%d", reg, length);
+	return usb_control_msg(dev->udev,
+			       usb_rcvctrlpipe(dev->udev, 0),
+			       DM_READ_REGS,
+			       USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+			       0, reg, data, length, USB_CTRL_SET_TIMEOUT);
+}
+
+static int dm_read_reg(struct usbnet *dev, u8 reg, u8 *value)
+{
+	return dm_read(dev, reg, 1, value);
+}
+
+static int dm_write(struct usbnet *dev, u8 reg, u16 length, void *data)
+{
+	devdbg(dev, "dm_write() reg=0x%02x, length=%d", reg, length);
+	return usb_control_msg(dev->udev,
+			       usb_sndctrlpipe(dev->udev, 0),
+			       DM_WRITE_REGS,
+			       USB_DIR_OUT | USB_TYPE_VENDOR |USB_RECIP_DEVICE,
+			       0, reg, data, length, USB_CTRL_SET_TIMEOUT);
+}
+
+static int dm_write_reg(struct usbnet *dev, u8 reg, u8 value)
+{
+	devdbg(dev, "dm_write_reg() reg=0x%02x, value=0x%02x", reg, value);
+	return usb_control_msg(dev->udev,
+			       usb_sndctrlpipe(dev->udev, 0),
+			       DM_WRITE_REG,
+			       USB_DIR_OUT | USB_TYPE_VENDOR |USB_RECIP_DEVICE,
+			       value, reg, 0, 0, USB_CTRL_SET_TIMEOUT);
+}
+
+static void dm_write_async_callback(struct urb *urb)
+{
+	struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
+
+	if (urb->status < 0)
+		printk(KERN_DEBUG "dm_write_async_callback() failed with %d",
+		       urb->status);
+
+	kfree(req);
+	usb_free_urb(urb);
+}
+
+static void dm_write_async(struct usbnet *dev, u8 reg, u16 length, void *data)
+{
+	struct usb_ctrlrequest *req;
+	struct urb *urb;
+	int status;
+
+	devdbg(dev, "dm_write_async() reg=0x%02x length=%d", reg, length);
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		deverr(dev, "Error allocating URB in dm_write_async!");
+		return;
+	}
+
+	req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
+	if (!req) {
+		deverr(dev, "Failed to allocate memory for control request");
+		usb_free_urb(urb);
+		return;
+	}
+
+	req->bRequestType = USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE;
+	req->bRequest = DM_WRITE_REGS;
+	req->wValue = 0;
+	req->wIndex = cpu_to_le16(reg);
+	req->wLength = cpu_to_le16(length);
+
+	usb_fill_control_urb(urb, dev->udev,
+			     usb_sndctrlpipe(dev->udev, 0),
+			     (void *)req, data, length,
+			     dm_write_async_callback, req);
+
+	status = usb_submit_urb(urb, GFP_ATOMIC);
+	if (status < 0) {
+		deverr(dev, "Error submitting the control message: status=%d",
+		       status);
+		kfree(req);
+		usb_free_urb(urb);
+	}
+}
+
+static void dm_write_reg_async(struct usbnet *dev, u8 reg, u8 value)
+{
+	struct usb_ctrlrequest *req;
+	struct urb *urb;
+	int status;
+
+	devdbg(dev, "dm_write_reg_async() reg=0x%02x value=0x%02x",
+	       reg, value);
+
+	urb = usb_alloc_urb(0, GFP_ATOMIC);
+	if (!urb) {
+		deverr(dev, "Error allocating URB in dm_write_async!");
+		return;
+	}
+
+	req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC);
+	if (!req) {
+		deverr(dev, "Failed to allocate memory for control request");
+		usb_free_urb(urb);
+		return;
+	}
+
+	req->bRequestType = USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE;
+	req->bRequest = DM_WRITE_REG;
+	req->wValue = cpu_to_le16(value);
+	req->wIndex = cpu_to_le16(reg);
+	req->wLength = 0;
+
+	usb_fill_control_urb(urb, dev->udev,
+			     usb_sndctrlpipe(dev->udev, 0),
+			     (void *)req, 0, 0, dm_write_async_callback, req);
+
+	status = usb_submit_urb(urb, GFP_ATOMIC);
+	if (status < 0) {
+		deverr(dev, "Error submitting the control message: status=%d",
+		       status);
+		kfree(req);
+		usb_free_urb(urb);
+	}
+}
+
+static int dm_read_shared_word(struct usbnet *dev, int phy, u8 reg, u16 *value)
+{
+	int ret, i;
+
+	mutex_lock(&dev->phy_mutex);
+
+	dm_write_reg(dev, DM_SHARED_ADDR, phy ? (reg | 0x40) : reg);
+	dm_write_reg(dev, DM_SHARED_CTRL, phy ? 0xc : 0x4);
+
+	for (i = 0; i < DM_TIMEOUT; i++) {
+		u8 tmp;
+
+		udelay(1);
+		ret = dm_read_reg(dev, DM_SHARED_CTRL, &tmp);
+		if (ret < 0)
+			goto out;
+
+		/* ready */
+		if ((tmp & 1) == 0)
+			break;
+	}
+
+	if (i == DM_TIMEOUT) {
+		deverr(dev, "%s read timed out!", phy ? "phy" : "eeprom");
+		ret = -EIO;
+		goto out;
+	}
+
+	dm_write_reg(dev, DM_SHARED_CTRL, 0x0);
+	ret = dm_read(dev, DM_SHARED_DATA, 2, value);
+
+	devdbg(dev, "read shared %d 0x%02x returned 0x%04x, %d",
+	       phy, reg, *value, ret);
+
+ out:
+	mutex_unlock(&dev->phy_mutex);
+	return ret;
+}
+
+static int dm_write_shared_word(struct usbnet *dev, int phy, u8 reg, u16 value)
+{
+	int ret, i;
+
+	mutex_lock(&dev->phy_mutex);
+
+	ret = dm_write(dev, DM_SHARED_DATA, 2, &value);
+	if (ret < 0)
+		goto out;
+
+	dm_write_reg(dev, DM_SHARED_ADDR, phy ? (reg | 0x40) : reg);
+	dm_write_reg(dev, DM_SHARED_CTRL, phy ? 0x1c : 0x14);
+
+	for (i = 0; i < DM_TIMEOUT; i++) {
+		u8 tmp;
+
+		udelay(1);
+		ret = dm_read_reg(dev, DM_SHARED_CTRL, &tmp);
+		if (ret < 0)
+			goto out;
+
+		/* ready */
+		if ((tmp & 1) == 0)
+			break;
+	}
+
+	if (i == DM_TIMEOUT) {
+		deverr(dev, "%s write timed out!", phy ? "phy" : "eeprom");
+		ret = -EIO;
+		goto out;
+	}
+
+	dm_write_reg(dev, DM_SHARED_CTRL, 0x0);
+
+out:
+	mutex_unlock(&dev->phy_mutex);
+	return ret;
+}
+
+static int dm_read_eeprom_word(struct usbnet *dev, u8 offset, void *value)
+{
+	return dm_read_shared_word(dev, 0, offset, value);
+}
+
+
+
+static int dm9601_get_eeprom_len(struct net_device *dev)
+{
+	return DM_EEPROM_LEN;
+}
+
+static int dm9601_get_eeprom(struct net_device *net,
+			     struct ethtool_eeprom *eeprom, u8 * data)
+{
+	struct usbnet *dev = netdev_priv(net);
+	u16 *ebuf = (u16 *) data;
+	int i;
+
+	/* access is 16bit */
+	if ((eeprom->offset % 2) || (eeprom->len % 2))
+		return -EINVAL;
+
+	for (i = 0; i < eeprom->len / 2; i++) {
+		if (dm_read_eeprom_word(dev, eeprom->offset / 2 + i,
+					&ebuf[i]) < 0)
+			return -EINVAL;
+	}
+	return 0;
+}
+
+static int dm9601_mdio_read(struct net_device *netdev, int phy_id, int loc)
+{
+	struct usbnet *dev = netdev_priv(netdev);
+
+	u16 res;
+
+	if (phy_id) {
+		devdbg(dev, "Only internal phy supported");
+		return 0;
+	}
+
+	dm_read_shared_word(dev, 1, loc, &res);
+
+	devdbg(dev,
+	       "dm9601_mdio_read() phy_id=0x%02x, loc=0x%02x, returns=0x%04x",
+	       phy_id, loc, le16_to_cpu(res));
+
+	return le16_to_cpu(res);
+}
+
+static void dm9601_mdio_write(struct net_device *netdev, int phy_id, int loc,
+			      int val)
+{
+	struct usbnet *dev = netdev_priv(netdev);
+	u16 res = cpu_to_le16(val);
+
+	if (phy_id) {
+		devdbg(dev, "Only internal phy supported");
+		return;
+	}
+
+	devdbg(dev,"dm9601_mdio_write() phy_id=0x%02x, loc=0x%02x, val=0x%04x",
+	       phy_id, loc, val);
+
+	dm_write_shared_word(dev, 1, loc, res);
+}
+
+static void dm9601_get_drvinfo(struct net_device *net,
+			       struct ethtool_drvinfo *info)
+{
+	/* Inherit standard device info */
+	usbnet_get_drvinfo(net, info);
+	info->eedump_len = DM_EEPROM_LEN;
+}
+
+static u32 dm9601_get_link(struct net_device *net)
+{
+	struct usbnet *dev = netdev_priv(net);
+
+	return mii_link_ok(&dev->mii);
+}
+
+static int dm9601_ioctl(struct net_device *net, struct ifreq *rq, int cmd)
+{
+	struct usbnet *dev = netdev_priv(net);
+
+	return generic_mii_ioctl(&dev->mii, if_mii(rq), cmd, NULL);
+}
+
+static struct ethtool_ops dm9601_ethtool_ops = {
+	.get_drvinfo	= dm9601_get_drvinfo,
+	.get_link	= dm9601_get_link,
+	.get_msglevel	= usbnet_get_msglevel,
+	.set_msglevel	= usbnet_set_msglevel,
+	.get_eeprom_len	= dm9601_get_eeprom_len,
+	.get_eeprom	= dm9601_get_eeprom,
+	.get_settings	= usbnet_get_settings,
+	.set_settings	= usbnet_set_settings,
+	.nway_reset	= usbnet_nway_reset,
+};
+
+static void dm9601_set_multicast(struct net_device *net)
+{
+	struct usbnet *dev = netdev_priv(net);
+	/* We use the 20 byte dev->data for our 8 byte filter buffer
+	 * to avoid allocating memory that is tricky to free later */
+	u8 *hashes = (u8 *) & dev->data;
+	u8 rx_ctl = 0x01;
+
+	memset(hashes, 0x00, DM_MCAST_SIZE);
+	hashes[DM_MCAST_SIZE - 1] |= 0x80;	/* broadcast address */
+
+	if (net->flags & IFF_PROMISC) {
+		rx_ctl |= 0x02;
+	} else if (net->flags & IFF_ALLMULTI || net->mc_count > DM_MAX_MCAST) {
+		rx_ctl |= 0x04;
+	} else if (net->mc_count) {
+		struct dev_mc_list *mc_list = net->mc_list;
+		int i;
+
+		for (i = 0; i < net->mc_count; i++) {
+			u32 crc = ether_crc(ETH_ALEN, mc_list->dmi_addr) >> 26;
+			hashes[crc >> 3] |= 1 << (crc & 0x7);
+		}
+	}
+
+	dm_write_async(dev, DM_MCAST_ADDR, DM_MCAST_SIZE, hashes);
+	dm_write_reg_async(dev, DM_RX_CTRL, rx_ctl);
+}
+
+static int dm9601_bind(struct usbnet *dev, struct usb_interface *intf)
+{
+	int ret;
+
+	ret = usbnet_get_endpoints(dev, intf);
+	if (ret)
+		goto out;
+
+	dev->net->do_ioctl = dm9601_ioctl;
+	dev->net->set_multicast_list = dm9601_set_multicast;
+	dev->net->ethtool_ops = &dm9601_ethtool_ops;
+	dev->net->hard_header_len += DM_TX_OVERHEAD;
+	dev->hard_mtu = dev->net->mtu + dev->net->hard_header_len;
+	dev->rx_urb_size = dev->net->mtu + DM_RX_OVERHEAD;
+
+	dev->mii.dev = dev->net;
+	dev->mii.mdio_read = dm9601_mdio_read;
+	dev->mii.mdio_write = dm9601_mdio_write;
+	dev->mii.phy_id_mask = 0x1f;
+	dev->mii.reg_num_mask = 0x1f;
+
+	/* reset */
+	ret = dm_write_reg(dev, DM_NET_CTRL, 1);
+	udelay(20);
+
+	/* read MAC */
+	ret = dm_read(dev, DM_PHY_ADDR, ETH_ALEN, dev->net->dev_addr);
+	if (ret < 0) {
+		printk(KERN_ERR "Error reading MAC address\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+
+	/* power up phy */
+	dm_write_reg(dev, DM_GPR_CTRL, 1);
+	dm_write_reg(dev, DM_GPR_DATA, 0);
+
+	/* receive broadcast packets */
+	dm9601_set_multicast(dev->net);
+
+	dm9601_mdio_write(dev->net, dev->mii.phy_id, MII_BMCR, BMCR_RESET);
+	dm9601_mdio_write(dev->net, dev->mii.phy_id, MII_ADVERTISE,
+			  ADVERTISE_ALL | ADVERTISE_CSMA | ADVERTISE_PAUSE_CAP);
+	mii_nway_restart(&dev->mii);
+
+out:
+	return ret;
+}
+
+static int dm9601_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
+{
+	u8 status;
+	int len;
+
+	/* format:
+	   b0: rx status
+	   b1: packet length (incl crc) low
+	   b2: packet length (incl crc) high
+	   b3..n-4: packet data
+	   bn-3..bn: ethernet crc
+	 */
+
+	if (unlikely(skb->len < DM_RX_OVERHEAD)) {
+		dev_err(&dev->udev->dev, "unexpected tiny rx frame\n");
+		return 0;
+	}
+
+	status = skb->data[0];
+	len = (skb->data[1] | (skb->data[2] << 8)) - 4;
+
+	if (unlikely(status & 0xbf)) {
+		if (status & 0x01) dev->stats.rx_fifo_errors++;
+		if (status & 0x02) dev->stats.rx_crc_errors++;
+		if (status & 0x04) dev->stats.rx_frame_errors++;
+		if (status & 0x20) dev->stats.rx_missed_errors++;
+		if (status & 0x90) dev->stats.rx_length_errors++;
+		return 0;
+	}
+
+	skb_pull(skb, 3);
+	skb_trim(skb, len);
+
+	return 1;
+}
+
+static struct sk_buff *dm9601_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
+				       gfp_t flags)
+{
+	int len;
+
+	/* format:
+	   b0: packet length low
+	   b1: packet length high
+	   b3..n: packet data
+	*/
+
+	if (skb_headroom(skb) < DM_TX_OVERHEAD) {
+		struct sk_buff *skb2;
+
+		skb2 = skb_copy_expand(skb, DM_TX_OVERHEAD, 0, flags);
+		dev_kfree_skb_any(skb);
+		skb = skb2;
+		if (!skb)
+			return NULL;
+	}
+
+	__skb_push(skb, DM_TX_OVERHEAD);
+
+	len = skb->len;
+	/* usbnet adds padding if length is a multiple of packet size
+	   if so, adjust length value in header */
+	if ((len % dev->maxpacket) == 0)
+		len++;
+
+	skb->data[0] = len;
+	skb->data[1] = len >> 8;
+
+	return skb;
+}
+
+static void dm9601_status(struct usbnet *dev, struct urb *urb)
+{
+	int link;
+	u8 *buf;
+
+	/* format:
+	   b0: net status
+	   b1: tx status 1
+	   b2: tx status 2
+	   b3: rx status
+	   b4: rx overflow
+	   b5: rx count
+	   b6: tx count
+	   b7: gpr
+	*/
+
+	if (urb->actual_length < 8)
+		return;
+
+	buf = urb->transfer_buffer;
+
+	link = !!(buf[0] & 0x40);
+	if (netif_carrier_ok(dev->net) != link) {
+		if (link) {
+			netif_carrier_on(dev->net);
+			usbnet_defer_kevent (dev, EVENT_LINK_RESET);
+		}
+		else
+			netif_carrier_off(dev->net);
+		devdbg(dev, "Link Status is: %d", link);
+	}
+}
+
+static int dm9601_link_reset(struct usbnet *dev)
+{
+	struct ethtool_cmd ecmd;
+
+	mii_check_media(&dev->mii, 1, 1);
+	mii_ethtool_gset(&dev->mii, &ecmd);
+
+	devdbg(dev, "link_reset() speed: %d duplex: %d",
+	       ecmd.speed, ecmd.duplex);
+
+	return 0;
+}
+
+static const struct driver_info dm9601_info = {
+	.description	= "Davicom DM9601 USB Ethernet",
+	.flags		= FLAG_ETHER,
+	.bind		= dm9601_bind,
+	.rx_fixup	= dm9601_rx_fixup,
+	.tx_fixup	= dm9601_tx_fixup,
+	.status		= dm9601_status,
+	.link_reset	= dm9601_link_reset,
+	.reset		= dm9601_link_reset,
+};
+
+static const struct usb_device_id products[] = {
+	{
+	 USB_DEVICE(0x0a46, 0x9601),	/* Davicom USB-100 */
+	 .driver_info = (unsigned long)&dm9601_info,
+	 },
+	{},			// END
+};
+
+MODULE_DEVICE_TABLE(usb, products);
+
+static struct usb_driver dm9601_driver = {
+	.name = "dm9601",
+	.id_table = products,
+	.probe = usbnet_probe,
+	.disconnect = usbnet_disconnect,
+	.suspend = usbnet_suspend,
+	.resume = usbnet_resume,
+};
+
+static int __init dm9601_init(void)
+{
+	return usb_register(&dm9601_driver);
+}
+
+static void __exit dm9601_exit(void)
+{
+	usb_deregister(&dm9601_driver);
+}
+
+module_init(dm9601_init);
+module_exit(dm9601_exit);
+
+MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>");
+MODULE_DESCRIPTION("Davicom DM9601 USB 1.1 ethernet devices");
+MODULE_LICENSE("GPL");