1/*
2 * MosChips MCS7830 based USB 2.0 Ethernet Devices
3 *
4 * based on usbnet.c, asix.c and the vendor provided mcs7830 driver
5 *
6 * Copyright (C) 2006 Arnd Bergmann <arnd@arndb.de>
7 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
8 * Copyright (C) 2005 Phil Chang <pchang23@sbcglobal.net>
9 * Copyright (c) 2002-2003 TiVo Inc.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
24 */
25
26#include <linux/crc32.h>
27#include <linux/etherdevice.h>
28#include <linux/ethtool.h>
29#include <linux/init.h>
30#include <linux/mii.h>
31#include <linux/module.h>
32#include <linux/netdevice.h>
33#include <linux/usb.h>
34
35#include "usbnet.h"
36
37/* requests */
38#define MCS7830_RD_BMREQ	(USB_DIR_IN  | USB_TYPE_VENDOR | \
39				 USB_RECIP_DEVICE)
40#define MCS7830_WR_BMREQ	(USB_DIR_OUT | USB_TYPE_VENDOR | \
41				 USB_RECIP_DEVICE)
42#define MCS7830_RD_BREQ		0x0E
43#define MCS7830_WR_BREQ		0x0D
44
45#define MCS7830_CTRL_TIMEOUT	1000
46#define MCS7830_MAX_MCAST	64
47
48#define MCS7830_VENDOR_ID	0x9710
49#define MCS7830_PRODUCT_ID	0x7830
50
51#define MCS7830_MII_ADVERTISE	(ADVERTISE_PAUSE_CAP | ADVERTISE_100FULL | \
52				 ADVERTISE_100HALF | ADVERTISE_10FULL | \
53				 ADVERTISE_10HALF | ADVERTISE_CSMA)
54
55/* HIF_REG_XX coressponding index value */
56enum {
57	HIF_REG_MULTICAST_HASH			= 0x00,
58	HIF_REG_PACKET_GAP1			= 0x08,
59	HIF_REG_PACKET_GAP2			= 0x09,
60	HIF_REG_PHY_DATA			= 0x0a,
61	HIF_REG_PHY_CMD1			= 0x0c,
62	   HIF_REG_PHY_CMD1_READ		= 0x40,
63	   HIF_REG_PHY_CMD1_WRITE		= 0x20,
64	   HIF_REG_PHY_CMD1_PHYADDR		= 0x01,
65	HIF_REG_PHY_CMD2			= 0x0d,
66	   HIF_REG_PHY_CMD2_PEND_FLAG_BIT	= 0x80,
67	   HIF_REG_PHY_CMD2_READY_FLAG_BIT	= 0x40,
68	HIF_REG_CONFIG				= 0x0e,
69	   HIF_REG_CONFIG_CFG			= 0x80,
70	   HIF_REG_CONFIG_SPEED100		= 0x40,
71	   HIF_REG_CONFIG_FULLDUPLEX_ENABLE	= 0x20,
72	   HIF_REG_CONFIG_RXENABLE		= 0x10,
73	   HIF_REG_CONFIG_TXENABLE		= 0x08,
74	   HIF_REG_CONFIG_SLEEPMODE		= 0x04,
75	   HIF_REG_CONFIG_ALLMULTICAST		= 0x02,
76	   HIF_REG_CONFIG_PROMISCIOUS		= 0x01,
77	HIF_REG_ETHERNET_ADDR			= 0x0f,
78	HIF_REG_22				= 0x15,
79	HIF_REG_PAUSE_THRESHOLD			= 0x16,
80	   HIF_REG_PAUSE_THRESHOLD_DEFAULT	= 0,
81};
82
83struct mcs7830_data {
84	u8 multi_filter[8];
85	u8 config;
86};
87
88static const char driver_name[] = "MOSCHIP usb-ethernet driver";
89
90static int mcs7830_get_reg(struct usbnet *dev, u16 index, u16 size, void *data)
91{
92	struct usb_device *xdev = dev->udev;
93	int ret;
94
95	ret = usb_control_msg(xdev, usb_rcvctrlpipe(xdev, 0), MCS7830_RD_BREQ,
96			      MCS7830_RD_BMREQ, 0x0000, index, data,
97			      size, msecs_to_jiffies(MCS7830_CTRL_TIMEOUT));
98	return ret;
99}
100
101static int mcs7830_set_reg(struct usbnet *dev, u16 index, u16 size, void *data)
102{
103	struct usb_device *xdev = dev->udev;
104	int ret;
105
106	ret = usb_control_msg(xdev, usb_sndctrlpipe(xdev, 0), MCS7830_WR_BREQ,
107			      MCS7830_WR_BMREQ, 0x0000, index, data,
108			      size, msecs_to_jiffies(MCS7830_CTRL_TIMEOUT));
109	return ret;
110}
111
112static void mcs7830_async_cmd_callback(struct urb *urb)
113{
114	struct usb_ctrlrequest *req = (struct usb_ctrlrequest *)urb->context;
115
116	if (urb->status < 0)
117		printk(KERN_DEBUG "mcs7830_async_cmd_callback() failed with %d",
118			urb->status);
119
120	kfree(req);
121	usb_free_urb(urb);
122}
123
124static void mcs7830_set_reg_async(struct usbnet *dev, u16 index, u16 size, void *data)
125{
126	struct usb_ctrlrequest *req;
127	int ret;
128	struct urb *urb;
129
130	urb = usb_alloc_urb(0, GFP_ATOMIC);
131	if (!urb) {
132		dev_dbg(&dev->udev->dev, "Error allocating URB "
133				"in write_cmd_async!");
134		return;
135	}
136
137	req = kmalloc(sizeof *req, GFP_ATOMIC);
138	if (!req) {
139		dev_err(&dev->udev->dev, "Failed to allocate memory for "
140				"control request");
141		goto out;
142	}
143	req->bRequestType = MCS7830_WR_BMREQ;
144	req->bRequest = MCS7830_WR_BREQ;
145	req->wValue = 0;
146	req->wIndex = cpu_to_le16(index);
147	req->wLength = cpu_to_le16(size);
148
149	usb_fill_control_urb(urb, dev->udev,
150			     usb_sndctrlpipe(dev->udev, 0),
151			     (void *)req, data, size,
152			     mcs7830_async_cmd_callback, req);
153
154	ret = usb_submit_urb(urb, GFP_ATOMIC);
155	if (ret < 0) {
156		dev_err(&dev->udev->dev, "Error submitting the control "
157				"message: ret=%d", ret);
158		goto out;
159	}
160	return;
161out:
162	kfree(req);
163	usb_free_urb(urb);
164}
165
166static int mcs7830_get_address(struct usbnet *dev)
167{
168	int ret;
169	ret = mcs7830_get_reg(dev, HIF_REG_ETHERNET_ADDR, ETH_ALEN,
170				   dev->net->dev_addr);
171	if (ret < 0)
172		return ret;
173	return 0;
174}
175
176static int mcs7830_read_phy(struct usbnet *dev, u8 index)
177{
178	int ret;
179	int i;
180	__le16 val;
181
182	u8 cmd[2] = {
183		HIF_REG_PHY_CMD1_READ | HIF_REG_PHY_CMD1_PHYADDR,
184		HIF_REG_PHY_CMD2_PEND_FLAG_BIT | index,
185	};
186
187	mutex_lock(&dev->phy_mutex);
188	/* write the MII command */
189	ret = mcs7830_set_reg(dev, HIF_REG_PHY_CMD1, 2, cmd);
190	if (ret < 0)
191		goto out;
192
193	/* wait for the data to become valid, should be within < 1ms */
194	for (i = 0; i < 10; i++) {
195		ret = mcs7830_get_reg(dev, HIF_REG_PHY_CMD1, 2, cmd);
196		if ((ret < 0) || (cmd[1] & HIF_REG_PHY_CMD2_READY_FLAG_BIT))
197			break;
198		ret = -EIO;
199		msleep(1);
200	}
201	if (ret < 0)
202		goto out;
203
204	/* read actual register contents */
205	ret = mcs7830_get_reg(dev, HIF_REG_PHY_DATA, 2, &val);
206	if (ret < 0)
207		goto out;
208	ret = le16_to_cpu(val);
209	dev_dbg(&dev->udev->dev, "read PHY reg %02x: %04x (%d tries)\n",
210		index, val, i);
211out:
212	mutex_unlock(&dev->phy_mutex);
213	return ret;
214}
215
216static int mcs7830_write_phy(struct usbnet *dev, u8 index, u16 val)
217{
218	int ret;
219	int i;
220	__le16 le_val;
221
222	u8 cmd[2] = {
223		HIF_REG_PHY_CMD1_WRITE | HIF_REG_PHY_CMD1_PHYADDR,
224		HIF_REG_PHY_CMD2_PEND_FLAG_BIT | (index & 0x1F),
225	};
226
227	mutex_lock(&dev->phy_mutex);
228
229	/* write the new register contents */
230	le_val = cpu_to_le16(val);
231	ret = mcs7830_set_reg(dev, HIF_REG_PHY_DATA, 2, &le_val);
232	if (ret < 0)
233		goto out;
234
235	/* write the MII command */
236	ret = mcs7830_set_reg(dev, HIF_REG_PHY_CMD1, 2, cmd);
237	if (ret < 0)
238		goto out;
239
240	/* wait for the command to be accepted by the PHY */
241	for (i = 0; i < 10; i++) {
242		ret = mcs7830_get_reg(dev, HIF_REG_PHY_CMD1, 2, cmd);
243		if ((ret < 0) || (cmd[1] & HIF_REG_PHY_CMD2_READY_FLAG_BIT))
244			break;
245		ret = -EIO;
246		msleep(1);
247	}
248	if (ret < 0)
249		goto out;
250
251	ret = 0;
252	dev_dbg(&dev->udev->dev, "write PHY reg %02x: %04x (%d tries)\n",
253		index, val, i);
254out:
255	mutex_unlock(&dev->phy_mutex);
256	return ret;
257}
258
259/*
260 * This algorithm comes from the original mcs7830 version 1.4 driver,
261 * not sure if it is needed.
262 */
263static int mcs7830_set_autoneg(struct usbnet *dev, int ptrUserPhyMode)
264{
265	int ret;
266	/* Enable all media types */
267	ret = mcs7830_write_phy(dev, MII_ADVERTISE, MCS7830_MII_ADVERTISE);
268
269	/* First reset BMCR */
270	if (!ret)
271		ret = mcs7830_write_phy(dev, MII_BMCR, 0x0000);
272	/* Enable Auto Neg */
273	if (!ret)
274		ret = mcs7830_write_phy(dev, MII_BMCR, BMCR_ANENABLE);
275	/* Restart Auto Neg (Keep the Enable Auto Neg Bit Set) */
276	if (!ret)
277		ret = mcs7830_write_phy(dev, MII_BMCR,
278				BMCR_ANENABLE | BMCR_ANRESTART	);
279	return ret < 0 ? : 0;
280}
281
282
283/*
284 * if we can read register 22, the chip revision is C or higher
285 */
286static int mcs7830_get_rev(struct usbnet *dev)
287{
288	u8 dummy[2];
289	int ret;
290	ret = mcs7830_get_reg(dev, HIF_REG_22, 2, dummy);
291	if (ret > 0)
292		return 2; /* Rev C or later */
293	return 1; /* earlier revision */
294}
295
296/*
297 * On rev. C we need to set the pause threshold
298 */
299static void mcs7830_rev_C_fixup(struct usbnet *dev)
300{
301	u8 pause_threshold = HIF_REG_PAUSE_THRESHOLD_DEFAULT;
302	int retry;
303
304	for (retry = 0; retry < 2; retry++) {
305		if (mcs7830_get_rev(dev) == 2) {
306			dev_info(&dev->udev->dev, "applying rev.C fixup\n");
307			mcs7830_set_reg(dev, HIF_REG_PAUSE_THRESHOLD,
308					1, &pause_threshold);
309		}
310		msleep(1);
311	}
312}
313
314static int mcs7830_init_dev(struct usbnet *dev)
315{
316	int ret;
317	int retry;
318
319	/* Read MAC address from EEPROM */
320	ret = -EINVAL;
321	for (retry = 0; retry < 5 && ret; retry++)
322		ret = mcs7830_get_address(dev);
323	if (ret) {
324		dev_warn(&dev->udev->dev, "Cannot read MAC address\n");
325		goto out;
326	}
327
328	/* Set up PHY */
329	ret = mcs7830_set_autoneg(dev, 0);
330	if (ret) {
331		dev_info(&dev->udev->dev, "Cannot set autoneg\n");
332		goto out;
333	}
334
335	mcs7830_rev_C_fixup(dev);
336	ret = 0;
337out:
338	return ret;
339}
340
341static int mcs7830_mdio_read(struct net_device *netdev, int phy_id,
342			     int location)
343{
344	struct usbnet *dev = netdev->priv;
345	return mcs7830_read_phy(dev, location);
346}
347
348static void mcs7830_mdio_write(struct net_device *netdev, int phy_id,
349				int location, int val)
350{
351	struct usbnet *dev = netdev->priv;
352	mcs7830_write_phy(dev, location, val);
353}
354
355static int mcs7830_ioctl(struct net_device *net, struct ifreq *rq, int cmd)
356{
357	struct usbnet *dev = netdev_priv(net);
358	return generic_mii_ioctl(&dev->mii, if_mii(rq), cmd, NULL);
359}
360
361/* credits go to asix_set_multicast */
362static void mcs7830_set_multicast(struct net_device *net)
363{
364	struct usbnet *dev = netdev_priv(net);
365	struct mcs7830_data *data = (struct mcs7830_data *)&dev->data;
366
367	data->config = HIF_REG_CONFIG_TXENABLE;
368
369	/* this should not be needed, but it doesn't work otherwise */
370	data->config |= HIF_REG_CONFIG_ALLMULTICAST;
371
372	if (net->flags & IFF_PROMISC) {
373		data->config |= HIF_REG_CONFIG_PROMISCIOUS;
374	} else if (net->flags & IFF_ALLMULTI
375		   || net->mc_count > MCS7830_MAX_MCAST) {
376		data->config |= HIF_REG_CONFIG_ALLMULTICAST;
377	} else if (net->mc_count == 0) {
378		/* just broadcast and directed */
379	} else {
380		/* We use the 20 byte dev->data
381		 * for our 8 byte filter buffer
382		 * to avoid allocating memory that
383		 * is tricky to free later */
384		struct dev_mc_list *mc_list = net->mc_list;
385		u32 crc_bits;
386		int i;
387
388		memset(data->multi_filter, 0, sizeof data->multi_filter);
389
390		/* Build the multicast hash filter. */
391		for (i = 0; i < net->mc_count; i++) {
392			crc_bits = ether_crc(ETH_ALEN, mc_list->dmi_addr) >> 26;
393			data->multi_filter[crc_bits >> 3] |= 1 << (crc_bits & 7);
394			mc_list = mc_list->next;
395		}
396
397		mcs7830_set_reg_async(dev, HIF_REG_MULTICAST_HASH,
398				sizeof data->multi_filter,
399				data->multi_filter);
400	}
401
402	mcs7830_set_reg_async(dev, HIF_REG_CONFIG, 1, &data->config);
403}
404
405static int mcs7830_get_regs_len(struct net_device *net)
406{
407	struct usbnet *dev = netdev_priv(net);
408
409	switch (mcs7830_get_rev(dev)) {
410	case 1:
411		return 21;
412	case 2:
413		return 32;
414	}
415	return 0;
416}
417
418static void mcs7830_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *drvinfo)
419{
420	usbnet_get_drvinfo(net, drvinfo);
421	drvinfo->regdump_len = mcs7830_get_regs_len(net);
422}
423
424static void mcs7830_get_regs(struct net_device *net, struct ethtool_regs *regs, void *data)
425{
426	struct usbnet *dev = netdev_priv(net);
427
428	regs->version = mcs7830_get_rev(dev);
429	mcs7830_get_reg(dev, 0, regs->len, data);
430}
431
432static struct ethtool_ops mcs7830_ethtool_ops = {
433	.get_drvinfo		= mcs7830_get_drvinfo,
434	.get_regs_len		= mcs7830_get_regs_len,
435	.get_regs		= mcs7830_get_regs,
436
437	/* common usbnet calls */
438	.get_link		= usbnet_get_link,
439	.get_msglevel		= usbnet_get_msglevel,
440	.set_msglevel		= usbnet_set_msglevel,
441	.get_settings		= usbnet_get_settings,
442	.set_settings		= usbnet_set_settings,
443	.nway_reset		= usbnet_nway_reset,
444};
445
446static int mcs7830_bind(struct usbnet *dev, struct usb_interface *udev)
447{
448	struct net_device *net = dev->net;
449	int ret;
450
451	ret = mcs7830_init_dev(dev);
452	if (ret)
453		goto out;
454
455	net->do_ioctl = mcs7830_ioctl;
456	net->ethtool_ops = &mcs7830_ethtool_ops;
457	net->set_multicast_list = mcs7830_set_multicast;
458	mcs7830_set_multicast(net);
459
460	/* reserve space for the status byte on rx */
461	dev->rx_urb_size = ETH_FRAME_LEN + 1;
462
463	dev->mii.mdio_read = mcs7830_mdio_read;
464	dev->mii.mdio_write = mcs7830_mdio_write;
465	dev->mii.dev = net;
466	dev->mii.phy_id_mask = 0x3f;
467	dev->mii.reg_num_mask = 0x1f;
468	dev->mii.phy_id = *((u8 *) net->dev_addr + 1);
469
470	ret = usbnet_get_endpoints(dev, udev);
471out:
472	return ret;
473}
474
475/* The chip always appends a status bytes that we need to strip */
476static int mcs7830_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
477{
478	u8 status;
479
480	if (skb->len == 0) {
481		dev_err(&dev->udev->dev, "unexpected empty rx frame\n");
482		return 0;
483	}
484
485	skb_trim(skb, skb->len - 1);
486	status = skb->data[skb->len];
487
488	if (status != 0x20)
489		dev_dbg(&dev->udev->dev, "rx fixup status %x\n", status);
490
491	return skb->len > 0;
492}
493
494static const struct driver_info moschip_info = {
495	.description	= "MOSCHIP 7830 usb-NET adapter",
496	.bind		= mcs7830_bind,
497	.rx_fixup	= mcs7830_rx_fixup,
498	.flags		= FLAG_ETHER,
499	.in		= 1,
500	.out		= 2,
501};
502
503static const struct usb_device_id products[] = {
504	{
505		USB_DEVICE(MCS7830_VENDOR_ID, MCS7830_PRODUCT_ID),
506		.driver_info = (unsigned long) &moschip_info,
507	},
508	{},
509};
510MODULE_DEVICE_TABLE(usb, products);
511
512static struct usb_driver mcs7830_driver = {
513	.name = driver_name,
514	.id_table = products,
515	.probe = usbnet_probe,
516	.disconnect = usbnet_disconnect,
517	.suspend = usbnet_suspend,
518	.resume = usbnet_resume,
519};
520
521static int __init mcs7830_init(void)
522{
523	return usb_register(&mcs7830_driver);
524}
525module_init(mcs7830_init);
526
527static void __exit mcs7830_exit(void)
528{
529	usb_deregister(&mcs7830_driver);
530}
531module_exit(mcs7830_exit);
532
533MODULE_DESCRIPTION("USB to network adapter MCS7830)");
534MODULE_LICENSE("GPL");
535