xref: /openbmc/linux/drivers/net/usb/sr9700.c (revision 4aea96f4)
1 /*
2  * CoreChip-sz SR9700 one chip USB 1.1 Ethernet Devices
3  *
4  * Author : Liu Junliang <liujunliang_ljl@163.com>
5  *
6  * Based on dm9601.c
7  *
8  * This file is licensed under the terms of the GNU General Public License
9  * version 2.  This program is licensed "as is" without any warranty of any
10  * kind, whether express or implied.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/sched.h>
15 #include <linux/stddef.h>
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/ethtool.h>
19 #include <linux/mii.h>
20 #include <linux/usb.h>
21 #include <linux/crc32.h>
22 #include <linux/usb/usbnet.h>
23 
24 #include "sr9700.h"
25 
26 static int sr_read(struct usbnet *dev, u8 reg, u16 length, void *data)
27 {
28 	int err;
29 
30 	err = usbnet_read_cmd(dev, SR_RD_REGS, SR_REQ_RD_REG, 0, reg, data,
31 			      length);
32 	if ((err != length) && (err >= 0))
33 		err = -EINVAL;
34 	return err;
35 }
36 
37 static int sr_write(struct usbnet *dev, u8 reg, u16 length, void *data)
38 {
39 	int err;
40 
41 	err = usbnet_write_cmd(dev, SR_WR_REGS, SR_REQ_WR_REG, 0, reg, data,
42 			       length);
43 	if ((err >= 0) && (err < length))
44 		err = -EINVAL;
45 	return err;
46 }
47 
48 static int sr_read_reg(struct usbnet *dev, u8 reg, u8 *value)
49 {
50 	return sr_read(dev, reg, 1, value);
51 }
52 
53 static int sr_write_reg(struct usbnet *dev, u8 reg, u8 value)
54 {
55 	return usbnet_write_cmd(dev, SR_WR_REGS, SR_REQ_WR_REG,
56 				value, reg, NULL, 0);
57 }
58 
59 static void sr_write_async(struct usbnet *dev, u8 reg, u16 length, void *data)
60 {
61 	usbnet_write_cmd_async(dev, SR_WR_REGS, SR_REQ_WR_REG,
62 			       0, reg, data, length);
63 }
64 
65 static void sr_write_reg_async(struct usbnet *dev, u8 reg, u8 value)
66 {
67 	usbnet_write_cmd_async(dev, SR_WR_REGS, SR_REQ_WR_REG,
68 			       value, reg, NULL, 0);
69 }
70 
71 static int wait_phy_eeprom_ready(struct usbnet *dev, int phy)
72 {
73 	int i;
74 
75 	for (i = 0; i < SR_SHARE_TIMEOUT; i++) {
76 		u8 tmp = 0;
77 		int ret;
78 
79 		udelay(1);
80 		ret = sr_read_reg(dev, SR_EPCR, &tmp);
81 		if (ret < 0)
82 			return ret;
83 
84 		/* ready */
85 		if (!(tmp & EPCR_ERRE))
86 			return 0;
87 	}
88 
89 	netdev_err(dev->net, "%s write timed out!\n", phy ? "phy" : "eeprom");
90 
91 	return -EIO;
92 }
93 
94 static int sr_share_read_word(struct usbnet *dev, int phy, u8 reg,
95 			      __le16 *value)
96 {
97 	int ret;
98 
99 	mutex_lock(&dev->phy_mutex);
100 
101 	sr_write_reg(dev, SR_EPAR, phy ? (reg | EPAR_PHY_ADR) : reg);
102 	sr_write_reg(dev, SR_EPCR, phy ? (EPCR_EPOS | EPCR_ERPRR) : EPCR_ERPRR);
103 
104 	ret = wait_phy_eeprom_ready(dev, phy);
105 	if (ret < 0)
106 		goto out_unlock;
107 
108 	sr_write_reg(dev, SR_EPCR, 0x0);
109 	ret = sr_read(dev, SR_EPDR, 2, value);
110 
111 	netdev_dbg(dev->net, "read shared %d 0x%02x returned 0x%04x, %d\n",
112 		   phy, reg, *value, ret);
113 
114 out_unlock:
115 	mutex_unlock(&dev->phy_mutex);
116 	return ret;
117 }
118 
119 static int sr_share_write_word(struct usbnet *dev, int phy, u8 reg,
120 			       __le16 value)
121 {
122 	int ret;
123 
124 	mutex_lock(&dev->phy_mutex);
125 
126 	ret = sr_write(dev, SR_EPDR, 2, &value);
127 	if (ret < 0)
128 		goto out_unlock;
129 
130 	sr_write_reg(dev, SR_EPAR, phy ? (reg | EPAR_PHY_ADR) : reg);
131 	sr_write_reg(dev, SR_EPCR, phy ? (EPCR_WEP | EPCR_EPOS | EPCR_ERPRW) :
132 		    (EPCR_WEP | EPCR_ERPRW));
133 
134 	ret = wait_phy_eeprom_ready(dev, phy);
135 	if (ret < 0)
136 		goto out_unlock;
137 
138 	sr_write_reg(dev, SR_EPCR, 0x0);
139 
140 out_unlock:
141 	mutex_unlock(&dev->phy_mutex);
142 	return ret;
143 }
144 
145 static int sr_read_eeprom_word(struct usbnet *dev, u8 offset, void *value)
146 {
147 	return sr_share_read_word(dev, 0, offset, value);
148 }
149 
150 static int sr9700_get_eeprom_len(struct net_device *netdev)
151 {
152 	return SR_EEPROM_LEN;
153 }
154 
155 static int sr9700_get_eeprom(struct net_device *netdev,
156 			     struct ethtool_eeprom *eeprom, u8 *data)
157 {
158 	struct usbnet *dev = netdev_priv(netdev);
159 	__le16 *buf = (__le16 *)data;
160 	int ret = 0;
161 	int i;
162 
163 	/* access is 16bit */
164 	if ((eeprom->offset & 0x01) || (eeprom->len & 0x01))
165 		return -EINVAL;
166 
167 	for (i = 0; i < eeprom->len / 2; i++) {
168 		ret = sr_read_eeprom_word(dev, eeprom->offset / 2 + i, buf + i);
169 		if (ret < 0)
170 			break;
171 	}
172 
173 	return ret;
174 }
175 
176 static int sr_mdio_read(struct net_device *netdev, int phy_id, int loc)
177 {
178 	struct usbnet *dev = netdev_priv(netdev);
179 	__le16 res;
180 	int rc = 0;
181 
182 	if (phy_id) {
183 		netdev_dbg(netdev, "Only internal phy supported\n");
184 		return 0;
185 	}
186 
187 	/* Access NSR_LINKST bit for link status instead of MII_BMSR */
188 	if (loc == MII_BMSR) {
189 		u8 value;
190 
191 		sr_read_reg(dev, SR_NSR, &value);
192 		if (value & NSR_LINKST)
193 			rc = 1;
194 	}
195 	sr_share_read_word(dev, 1, loc, &res);
196 	if (rc == 1)
197 		res = le16_to_cpu(res) | BMSR_LSTATUS;
198 	else
199 		res = le16_to_cpu(res) & ~BMSR_LSTATUS;
200 
201 	netdev_dbg(netdev, "sr_mdio_read() phy_id=0x%02x, loc=0x%02x, returns=0x%04x\n",
202 		   phy_id, loc, res);
203 
204 	return res;
205 }
206 
207 static void sr_mdio_write(struct net_device *netdev, int phy_id, int loc,
208 			  int val)
209 {
210 	struct usbnet *dev = netdev_priv(netdev);
211 	__le16 res = cpu_to_le16(val);
212 
213 	if (phy_id) {
214 		netdev_dbg(netdev, "Only internal phy supported\n");
215 		return;
216 	}
217 
218 	netdev_dbg(netdev, "sr_mdio_write() phy_id=0x%02x, loc=0x%02x, val=0x%04x\n",
219 		   phy_id, loc, val);
220 
221 	sr_share_write_word(dev, 1, loc, res);
222 }
223 
224 static u32 sr9700_get_link(struct net_device *netdev)
225 {
226 	struct usbnet *dev = netdev_priv(netdev);
227 	u8 value = 0;
228 	int rc = 0;
229 
230 	/* Get the Link Status directly */
231 	sr_read_reg(dev, SR_NSR, &value);
232 	if (value & NSR_LINKST)
233 		rc = 1;
234 
235 	return rc;
236 }
237 
238 static int sr9700_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
239 {
240 	struct usbnet *dev = netdev_priv(netdev);
241 
242 	return generic_mii_ioctl(&dev->mii, if_mii(rq), cmd, NULL);
243 }
244 
245 static const struct ethtool_ops sr9700_ethtool_ops = {
246 	.get_drvinfo	= usbnet_get_drvinfo,
247 	.get_link	= sr9700_get_link,
248 	.get_msglevel	= usbnet_get_msglevel,
249 	.set_msglevel	= usbnet_set_msglevel,
250 	.get_eeprom_len	= sr9700_get_eeprom_len,
251 	.get_eeprom	= sr9700_get_eeprom,
252 	.nway_reset	= usbnet_nway_reset,
253 	.get_link_ksettings	= usbnet_get_link_ksettings,
254 	.set_link_ksettings	= usbnet_set_link_ksettings,
255 };
256 
257 static void sr9700_set_multicast(struct net_device *netdev)
258 {
259 	struct usbnet *dev = netdev_priv(netdev);
260 	/* We use the 20 byte dev->data for our 8 byte filter buffer
261 	 * to avoid allocating memory that is tricky to free later
262 	 */
263 	u8 *hashes = (u8 *)&dev->data;
264 	/* rx_ctl setting : enable, disable_long, disable_crc */
265 	u8 rx_ctl = RCR_RXEN | RCR_DIS_CRC | RCR_DIS_LONG;
266 
267 	memset(hashes, 0x00, SR_MCAST_SIZE);
268 	/* broadcast address */
269 	hashes[SR_MCAST_SIZE - 1] |= SR_MCAST_ADDR_FLAG;
270 	if (netdev->flags & IFF_PROMISC) {
271 		rx_ctl |= RCR_PRMSC;
272 	} else if (netdev->flags & IFF_ALLMULTI ||
273 		   netdev_mc_count(netdev) > SR_MCAST_MAX) {
274 		rx_ctl |= RCR_RUNT;
275 	} else if (!netdev_mc_empty(netdev)) {
276 		struct netdev_hw_addr *ha;
277 
278 		netdev_for_each_mc_addr(ha, netdev) {
279 			u32 crc = ether_crc(ETH_ALEN, ha->addr) >> 26;
280 			hashes[crc >> 3] |= 1 << (crc & 0x7);
281 		}
282 	}
283 
284 	sr_write_async(dev, SR_MAR, SR_MCAST_SIZE, hashes);
285 	sr_write_reg_async(dev, SR_RCR, rx_ctl);
286 }
287 
288 static int sr9700_set_mac_address(struct net_device *netdev, void *p)
289 {
290 	struct usbnet *dev = netdev_priv(netdev);
291 	struct sockaddr *addr = p;
292 
293 	if (!is_valid_ether_addr(addr->sa_data)) {
294 		netdev_err(netdev, "not setting invalid mac address %pM\n",
295 			   addr->sa_data);
296 		return -EINVAL;
297 	}
298 
299 	memcpy(netdev->dev_addr, addr->sa_data, netdev->addr_len);
300 	sr_write_async(dev, SR_PAR, 6, netdev->dev_addr);
301 
302 	return 0;
303 }
304 
305 static const struct net_device_ops sr9700_netdev_ops = {
306 	.ndo_open		= usbnet_open,
307 	.ndo_stop		= usbnet_stop,
308 	.ndo_start_xmit		= usbnet_start_xmit,
309 	.ndo_tx_timeout		= usbnet_tx_timeout,
310 	.ndo_change_mtu		= usbnet_change_mtu,
311 	.ndo_get_stats64	= usbnet_get_stats64,
312 	.ndo_validate_addr	= eth_validate_addr,
313 	.ndo_do_ioctl		= sr9700_ioctl,
314 	.ndo_set_rx_mode	= sr9700_set_multicast,
315 	.ndo_set_mac_address	= sr9700_set_mac_address,
316 };
317 
318 static int sr9700_bind(struct usbnet *dev, struct usb_interface *intf)
319 {
320 	struct net_device *netdev;
321 	struct mii_if_info *mii;
322 	int ret;
323 
324 	ret = usbnet_get_endpoints(dev, intf);
325 	if (ret)
326 		goto out;
327 
328 	netdev = dev->net;
329 
330 	netdev->netdev_ops = &sr9700_netdev_ops;
331 	netdev->ethtool_ops = &sr9700_ethtool_ops;
332 	netdev->hard_header_len += SR_TX_OVERHEAD;
333 	dev->hard_mtu = netdev->mtu + netdev->hard_header_len;
334 	/* bulkin buffer is preferably not less than 3K */
335 	dev->rx_urb_size = 3072;
336 
337 	mii = &dev->mii;
338 	mii->dev = netdev;
339 	mii->mdio_read = sr_mdio_read;
340 	mii->mdio_write = sr_mdio_write;
341 	mii->phy_id_mask = 0x1f;
342 	mii->reg_num_mask = 0x1f;
343 
344 	sr_write_reg(dev, SR_NCR, NCR_RST);
345 	udelay(20);
346 
347 	/* read MAC
348 	 * After Chip Power on, the Chip will reload the MAC from
349 	 * EEPROM automatically to PAR. In case there is no EEPROM externally,
350 	 * a default MAC address is stored in PAR for making chip work properly.
351 	 */
352 	if (sr_read(dev, SR_PAR, ETH_ALEN, netdev->dev_addr) < 0) {
353 		netdev_err(netdev, "Error reading MAC address\n");
354 		ret = -ENODEV;
355 		goto out;
356 	}
357 
358 	/* power up and reset phy */
359 	sr_write_reg(dev, SR_PRR, PRR_PHY_RST);
360 	/* at least 10ms, here 20ms for safe */
361 	msleep(20);
362 	sr_write_reg(dev, SR_PRR, 0);
363 	/* at least 1ms, here 2ms for reading right register */
364 	udelay(2 * 1000);
365 
366 	/* receive broadcast packets */
367 	sr9700_set_multicast(netdev);
368 
369 	sr_mdio_write(netdev, mii->phy_id, MII_BMCR, BMCR_RESET);
370 	sr_mdio_write(netdev, mii->phy_id, MII_ADVERTISE, ADVERTISE_ALL |
371 		      ADVERTISE_CSMA | ADVERTISE_PAUSE_CAP);
372 	mii_nway_restart(mii);
373 
374 out:
375 	return ret;
376 }
377 
378 static int sr9700_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
379 {
380 	struct sk_buff *sr_skb;
381 	int len;
382 
383 	/* skb content (packets) format :
384 	 *                    p0            p1            p2    ......    pm
385 	 *                 /      \
386 	 *            /                \
387 	 *        /                            \
388 	 *  /                                        \
389 	 * p0b0 p0b1 p0b2 p0b3 ...... p0b(n-4) p0b(n-3)...p0bn
390 	 *
391 	 * p0 : packet 0
392 	 * p0b0 : packet 0 byte 0
393 	 *
394 	 * b0: rx status
395 	 * b1: packet length (incl crc) low
396 	 * b2: packet length (incl crc) high
397 	 * b3..n-4: packet data
398 	 * bn-3..bn: ethernet packet crc
399 	 */
400 	if (unlikely(skb->len < SR_RX_OVERHEAD)) {
401 		netdev_err(dev->net, "unexpected tiny rx frame\n");
402 		return 0;
403 	}
404 
405 	/* one skb may contains multiple packets */
406 	while (skb->len > SR_RX_OVERHEAD) {
407 		if (skb->data[0] != 0x40)
408 			return 0;
409 
410 		/* ignore the CRC length */
411 		len = (skb->data[1] | (skb->data[2] << 8)) - 4;
412 
413 		if (len > ETH_FRAME_LEN)
414 			return 0;
415 
416 		/* the last packet of current skb */
417 		if (skb->len == (len + SR_RX_OVERHEAD))	{
418 			skb_pull(skb, 3);
419 			skb->len = len;
420 			skb_set_tail_pointer(skb, len);
421 			skb->truesize = len + sizeof(struct sk_buff);
422 			return 2;
423 		}
424 
425 		/* skb_clone is used for address align */
426 		sr_skb = skb_clone(skb, GFP_ATOMIC);
427 		if (!sr_skb)
428 			return 0;
429 
430 		sr_skb->len = len;
431 		sr_skb->data = skb->data + 3;
432 		skb_set_tail_pointer(sr_skb, len);
433 		sr_skb->truesize = len + sizeof(struct sk_buff);
434 		usbnet_skb_return(dev, sr_skb);
435 
436 		skb_pull(skb, len + SR_RX_OVERHEAD);
437 	};
438 
439 	return 0;
440 }
441 
442 static struct sk_buff *sr9700_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
443 				       gfp_t flags)
444 {
445 	int len;
446 
447 	/* SR9700 can only send out one ethernet packet at once.
448 	 *
449 	 * b0 b1 b2 b3 ...... b(n-4) b(n-3)...bn
450 	 *
451 	 * b0: rx status
452 	 * b1: packet length (incl crc) low
453 	 * b2: packet length (incl crc) high
454 	 * b3..n-4: packet data
455 	 * bn-3..bn: ethernet packet crc
456 	 */
457 
458 	len = skb->len;
459 
460 	if (skb_cow_head(skb, SR_TX_OVERHEAD)) {
461 		dev_kfree_skb_any(skb);
462 		return NULL;
463 	}
464 
465 	__skb_push(skb, SR_TX_OVERHEAD);
466 
467 	/* usbnet adds padding if length is a multiple of packet size
468 	 * if so, adjust length value in header
469 	 */
470 	if ((skb->len % dev->maxpacket) == 0)
471 		len++;
472 
473 	skb->data[0] = len;
474 	skb->data[1] = len >> 8;
475 
476 	return skb;
477 }
478 
479 static void sr9700_status(struct usbnet *dev, struct urb *urb)
480 {
481 	int link;
482 	u8 *buf;
483 
484 	/* format:
485 	   b0: net status
486 	   b1: tx status 1
487 	   b2: tx status 2
488 	   b3: rx status
489 	   b4: rx overflow
490 	   b5: rx count
491 	   b6: tx count
492 	   b7: gpr
493 	*/
494 
495 	if (urb->actual_length < 8)
496 		return;
497 
498 	buf = urb->transfer_buffer;
499 
500 	link = !!(buf[0] & 0x40);
501 	if (netif_carrier_ok(dev->net) != link) {
502 		usbnet_link_change(dev, link, 1);
503 		netdev_dbg(dev->net, "Link Status is: %d\n", link);
504 	}
505 }
506 
507 static int sr9700_link_reset(struct usbnet *dev)
508 {
509 	struct ethtool_cmd ecmd;
510 
511 	mii_check_media(&dev->mii, 1, 1);
512 	mii_ethtool_gset(&dev->mii, &ecmd);
513 
514 	netdev_dbg(dev->net, "link_reset() speed: %d duplex: %d\n",
515 		   ecmd.speed, ecmd.duplex);
516 
517 	return 0;
518 }
519 
520 static const struct driver_info sr9700_driver_info = {
521 	.description	= "CoreChip SR9700 USB Ethernet",
522 	.flags		= FLAG_ETHER,
523 	.bind		= sr9700_bind,
524 	.rx_fixup	= sr9700_rx_fixup,
525 	.tx_fixup	= sr9700_tx_fixup,
526 	.status		= sr9700_status,
527 	.link_reset	= sr9700_link_reset,
528 	.reset		= sr9700_link_reset,
529 };
530 
531 static const struct usb_device_id products[] = {
532 	{
533 		USB_DEVICE(0x0fe6, 0x9700),	/* SR9700 device */
534 		.driver_info = (unsigned long)&sr9700_driver_info,
535 	},
536 	{},			/* END */
537 };
538 
539 MODULE_DEVICE_TABLE(usb, products);
540 
541 static struct usb_driver sr9700_usb_driver = {
542 	.name		= "sr9700",
543 	.id_table	= products,
544 	.probe		= usbnet_probe,
545 	.disconnect	= usbnet_disconnect,
546 	.suspend	= usbnet_suspend,
547 	.resume		= usbnet_resume,
548 	.disable_hub_initiated_lpm = 1,
549 };
550 
551 module_usb_driver(sr9700_usb_driver);
552 
553 MODULE_AUTHOR("liujl <liujunliang_ljl@163.com>");
554 MODULE_DESCRIPTION("SR9700 one chip USB 1.1 USB to Ethernet device from http://www.corechip-sz.com/");
555 MODULE_LICENSE("GPL");
556