1 /*
2  * Ethernet driver for the WIZnet W5100/W5200/W5500 chip.
3  *
4  * Copyright (C) 2016 Akinobu Mita <akinobu.mita@gmail.com>
5  *
6  * Licensed under the GPL-2 or later.
7  *
8  * Datasheet:
9  * http://www.wiznet.co.kr/wp-content/uploads/wiznethome/Chip/W5100/Document/W5100_Datasheet_v1.2.6.pdf
10  * http://wiznethome.cafe24.com/wp-content/uploads/wiznethome/Chip/W5200/Documents/W5200_DS_V140E.pdf
11  * http://wizwiki.net/wiki/lib/exe/fetch.php?media=products:w5500:w5500_ds_v106e_141230.pdf
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/delay.h>
17 #include <linux/netdevice.h>
18 #include <linux/of_net.h>
19 #include <linux/spi/spi.h>
20 
21 #include "w5100.h"
22 
23 #define W5100_SPI_WRITE_OPCODE 0xf0
24 #define W5100_SPI_READ_OPCODE 0x0f
25 
26 static int w5100_spi_read(struct net_device *ndev, u32 addr)
27 {
28 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
29 	u8 cmd[3] = { W5100_SPI_READ_OPCODE, addr >> 8, addr & 0xff };
30 	u8 data;
31 	int ret;
32 
33 	ret = spi_write_then_read(spi, cmd, sizeof(cmd), &data, 1);
34 
35 	return ret ? ret : data;
36 }
37 
38 static int w5100_spi_write(struct net_device *ndev, u32 addr, u8 data)
39 {
40 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
41 	u8 cmd[4] = { W5100_SPI_WRITE_OPCODE, addr >> 8, addr & 0xff, data};
42 
43 	return spi_write_then_read(spi, cmd, sizeof(cmd), NULL, 0);
44 }
45 
46 static int w5100_spi_read16(struct net_device *ndev, u32 addr)
47 {
48 	u16 data;
49 	int ret;
50 
51 	ret = w5100_spi_read(ndev, addr);
52 	if (ret < 0)
53 		return ret;
54 	data = ret << 8;
55 	ret = w5100_spi_read(ndev, addr + 1);
56 
57 	return ret < 0 ? ret : data | ret;
58 }
59 
60 static int w5100_spi_write16(struct net_device *ndev, u32 addr, u16 data)
61 {
62 	int ret;
63 
64 	ret = w5100_spi_write(ndev, addr, data >> 8);
65 	if (ret)
66 		return ret;
67 
68 	return w5100_spi_write(ndev, addr + 1, data & 0xff);
69 }
70 
71 static int w5100_spi_readbulk(struct net_device *ndev, u32 addr, u8 *buf,
72 			      int len)
73 {
74 	int i;
75 
76 	for (i = 0; i < len; i++) {
77 		int ret = w5100_spi_read(ndev, addr + i);
78 
79 		if (ret < 0)
80 			return ret;
81 		buf[i] = ret;
82 	}
83 
84 	return 0;
85 }
86 
87 static int w5100_spi_writebulk(struct net_device *ndev, u32 addr, const u8 *buf,
88 			       int len)
89 {
90 	int i;
91 
92 	for (i = 0; i < len; i++) {
93 		int ret = w5100_spi_write(ndev, addr + i, buf[i]);
94 
95 		if (ret)
96 			return ret;
97 	}
98 
99 	return 0;
100 }
101 
102 static const struct w5100_ops w5100_spi_ops = {
103 	.may_sleep = true,
104 	.chip_id = W5100,
105 	.read = w5100_spi_read,
106 	.write = w5100_spi_write,
107 	.read16 = w5100_spi_read16,
108 	.write16 = w5100_spi_write16,
109 	.readbulk = w5100_spi_readbulk,
110 	.writebulk = w5100_spi_writebulk,
111 };
112 
113 #define W5200_SPI_WRITE_OPCODE 0x80
114 
115 struct w5200_spi_priv {
116 	/* Serialize access to cmd_buf */
117 	struct mutex cmd_lock;
118 
119 	/* DMA (thus cache coherency maintenance) requires the
120 	 * transfer buffers to live in their own cache lines.
121 	 */
122 	u8 cmd_buf[4] ____cacheline_aligned;
123 };
124 
125 static struct w5200_spi_priv *w5200_spi_priv(struct net_device *ndev)
126 {
127 	return w5100_ops_priv(ndev);
128 }
129 
130 static int w5200_spi_init(struct net_device *ndev)
131 {
132 	struct w5200_spi_priv *spi_priv = w5200_spi_priv(ndev);
133 
134 	mutex_init(&spi_priv->cmd_lock);
135 
136 	return 0;
137 }
138 
139 static int w5200_spi_read(struct net_device *ndev, u32 addr)
140 {
141 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
142 	u8 cmd[4] = { addr >> 8, addr & 0xff, 0, 1 };
143 	u8 data;
144 	int ret;
145 
146 	ret = spi_write_then_read(spi, cmd, sizeof(cmd), &data, 1);
147 
148 	return ret ? ret : data;
149 }
150 
151 static int w5200_spi_write(struct net_device *ndev, u32 addr, u8 data)
152 {
153 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
154 	u8 cmd[5] = { addr >> 8, addr & 0xff, W5200_SPI_WRITE_OPCODE, 1, data };
155 
156 	return spi_write_then_read(spi, cmd, sizeof(cmd), NULL, 0);
157 }
158 
159 static int w5200_spi_read16(struct net_device *ndev, u32 addr)
160 {
161 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
162 	u8 cmd[4] = { addr >> 8, addr & 0xff, 0, 2 };
163 	__be16 data;
164 	int ret;
165 
166 	ret = spi_write_then_read(spi, cmd, sizeof(cmd), &data, sizeof(data));
167 
168 	return ret ? ret : be16_to_cpu(data);
169 }
170 
171 static int w5200_spi_write16(struct net_device *ndev, u32 addr, u16 data)
172 {
173 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
174 	u8 cmd[6] = {
175 		addr >> 8, addr & 0xff,
176 		W5200_SPI_WRITE_OPCODE, 2,
177 		data >> 8, data & 0xff
178 	};
179 
180 	return spi_write_then_read(spi, cmd, sizeof(cmd), NULL, 0);
181 }
182 
183 static int w5200_spi_readbulk(struct net_device *ndev, u32 addr, u8 *buf,
184 			      int len)
185 {
186 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
187 	struct w5200_spi_priv *spi_priv = w5200_spi_priv(ndev);
188 	struct spi_transfer xfer[] = {
189 		{
190 			.tx_buf = spi_priv->cmd_buf,
191 			.len = sizeof(spi_priv->cmd_buf),
192 		},
193 		{
194 			.rx_buf = buf,
195 			.len = len,
196 		},
197 	};
198 	int ret;
199 
200 	mutex_lock(&spi_priv->cmd_lock);
201 
202 	spi_priv->cmd_buf[0] = addr >> 8;
203 	spi_priv->cmd_buf[1] = addr;
204 	spi_priv->cmd_buf[2] = len >> 8;
205 	spi_priv->cmd_buf[3] = len;
206 	ret = spi_sync_transfer(spi, xfer, ARRAY_SIZE(xfer));
207 
208 	mutex_unlock(&spi_priv->cmd_lock);
209 
210 	return ret;
211 }
212 
213 static int w5200_spi_writebulk(struct net_device *ndev, u32 addr, const u8 *buf,
214 			       int len)
215 {
216 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
217 	struct w5200_spi_priv *spi_priv = w5200_spi_priv(ndev);
218 	struct spi_transfer xfer[] = {
219 		{
220 			.tx_buf = spi_priv->cmd_buf,
221 			.len = sizeof(spi_priv->cmd_buf),
222 		},
223 		{
224 			.tx_buf = buf,
225 			.len = len,
226 		},
227 	};
228 	int ret;
229 
230 	mutex_lock(&spi_priv->cmd_lock);
231 
232 	spi_priv->cmd_buf[0] = addr >> 8;
233 	spi_priv->cmd_buf[1] = addr;
234 	spi_priv->cmd_buf[2] = W5200_SPI_WRITE_OPCODE | (len >> 8);
235 	spi_priv->cmd_buf[3] = len;
236 	ret = spi_sync_transfer(spi, xfer, ARRAY_SIZE(xfer));
237 
238 	mutex_unlock(&spi_priv->cmd_lock);
239 
240 	return ret;
241 }
242 
243 static const struct w5100_ops w5200_ops = {
244 	.may_sleep = true,
245 	.chip_id = W5200,
246 	.read = w5200_spi_read,
247 	.write = w5200_spi_write,
248 	.read16 = w5200_spi_read16,
249 	.write16 = w5200_spi_write16,
250 	.readbulk = w5200_spi_readbulk,
251 	.writebulk = w5200_spi_writebulk,
252 	.init = w5200_spi_init,
253 };
254 
255 #define W5500_SPI_BLOCK_SELECT(addr) (((addr) >> 16) & 0x1f)
256 #define W5500_SPI_READ_CONTROL(addr) (W5500_SPI_BLOCK_SELECT(addr) << 3)
257 #define W5500_SPI_WRITE_CONTROL(addr)	\
258 	((W5500_SPI_BLOCK_SELECT(addr) << 3) | BIT(2))
259 
260 struct w5500_spi_priv {
261 	/* Serialize access to cmd_buf */
262 	struct mutex cmd_lock;
263 
264 	/* DMA (thus cache coherency maintenance) requires the
265 	 * transfer buffers to live in their own cache lines.
266 	 */
267 	u8 cmd_buf[3] ____cacheline_aligned;
268 };
269 
270 static struct w5500_spi_priv *w5500_spi_priv(struct net_device *ndev)
271 {
272 	return w5100_ops_priv(ndev);
273 }
274 
275 static int w5500_spi_init(struct net_device *ndev)
276 {
277 	struct w5500_spi_priv *spi_priv = w5500_spi_priv(ndev);
278 
279 	mutex_init(&spi_priv->cmd_lock);
280 
281 	return 0;
282 }
283 
284 static int w5500_spi_read(struct net_device *ndev, u32 addr)
285 {
286 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
287 	u8 cmd[3] = {
288 		addr >> 8,
289 		addr,
290 		W5500_SPI_READ_CONTROL(addr)
291 	};
292 	u8 data;
293 	int ret;
294 
295 	ret = spi_write_then_read(spi, cmd, sizeof(cmd), &data, 1);
296 
297 	return ret ? ret : data;
298 }
299 
300 static int w5500_spi_write(struct net_device *ndev, u32 addr, u8 data)
301 {
302 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
303 	u8 cmd[4] = {
304 		addr >> 8,
305 		addr,
306 		W5500_SPI_WRITE_CONTROL(addr),
307 		data
308 	};
309 
310 	return spi_write_then_read(spi, cmd, sizeof(cmd), NULL, 0);
311 }
312 
313 static int w5500_spi_read16(struct net_device *ndev, u32 addr)
314 {
315 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
316 	u8 cmd[3] = {
317 		addr >> 8,
318 		addr,
319 		W5500_SPI_READ_CONTROL(addr)
320 	};
321 	__be16 data;
322 	int ret;
323 
324 	ret = spi_write_then_read(spi, cmd, sizeof(cmd), &data, sizeof(data));
325 
326 	return ret ? ret : be16_to_cpu(data);
327 }
328 
329 static int w5500_spi_write16(struct net_device *ndev, u32 addr, u16 data)
330 {
331 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
332 	u8 cmd[5] = {
333 		addr >> 8,
334 		addr,
335 		W5500_SPI_WRITE_CONTROL(addr),
336 		data >> 8,
337 		data
338 	};
339 
340 	return spi_write_then_read(spi, cmd, sizeof(cmd), NULL, 0);
341 }
342 
343 static int w5500_spi_readbulk(struct net_device *ndev, u32 addr, u8 *buf,
344 			      int len)
345 {
346 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
347 	struct w5500_spi_priv *spi_priv = w5500_spi_priv(ndev);
348 	struct spi_transfer xfer[] = {
349 		{
350 			.tx_buf = spi_priv->cmd_buf,
351 			.len = sizeof(spi_priv->cmd_buf),
352 		},
353 		{
354 			.rx_buf = buf,
355 			.len = len,
356 		},
357 	};
358 	int ret;
359 
360 	mutex_lock(&spi_priv->cmd_lock);
361 
362 	spi_priv->cmd_buf[0] = addr >> 8;
363 	spi_priv->cmd_buf[1] = addr;
364 	spi_priv->cmd_buf[2] = W5500_SPI_READ_CONTROL(addr);
365 	ret = spi_sync_transfer(spi, xfer, ARRAY_SIZE(xfer));
366 
367 	mutex_unlock(&spi_priv->cmd_lock);
368 
369 	return ret;
370 }
371 
372 static int w5500_spi_writebulk(struct net_device *ndev, u32 addr, const u8 *buf,
373 			       int len)
374 {
375 	struct spi_device *spi = to_spi_device(ndev->dev.parent);
376 	struct w5500_spi_priv *spi_priv = w5500_spi_priv(ndev);
377 	struct spi_transfer xfer[] = {
378 		{
379 			.tx_buf = spi_priv->cmd_buf,
380 			.len = sizeof(spi_priv->cmd_buf),
381 		},
382 		{
383 			.tx_buf = buf,
384 			.len = len,
385 		},
386 	};
387 	int ret;
388 
389 	mutex_lock(&spi_priv->cmd_lock);
390 
391 	spi_priv->cmd_buf[0] = addr >> 8;
392 	spi_priv->cmd_buf[1] = addr;
393 	spi_priv->cmd_buf[2] = W5500_SPI_WRITE_CONTROL(addr);
394 	ret = spi_sync_transfer(spi, xfer, ARRAY_SIZE(xfer));
395 
396 	mutex_unlock(&spi_priv->cmd_lock);
397 
398 	return ret;
399 }
400 
401 static const struct w5100_ops w5500_ops = {
402 	.may_sleep = true,
403 	.chip_id = W5500,
404 	.read = w5500_spi_read,
405 	.write = w5500_spi_write,
406 	.read16 = w5500_spi_read16,
407 	.write16 = w5500_spi_write16,
408 	.readbulk = w5500_spi_readbulk,
409 	.writebulk = w5500_spi_writebulk,
410 	.init = w5500_spi_init,
411 };
412 
413 static int w5100_spi_probe(struct spi_device *spi)
414 {
415 	const struct spi_device_id *id = spi_get_device_id(spi);
416 	const struct w5100_ops *ops;
417 	int priv_size;
418 	const void *mac = of_get_mac_address(spi->dev.of_node);
419 
420 	switch (id->driver_data) {
421 	case W5100:
422 		ops = &w5100_spi_ops;
423 		priv_size = 0;
424 		break;
425 	case W5200:
426 		ops = &w5200_ops;
427 		priv_size = sizeof(struct w5200_spi_priv);
428 		break;
429 	case W5500:
430 		ops = &w5500_ops;
431 		priv_size = sizeof(struct w5500_spi_priv);
432 		break;
433 	default:
434 		return -EINVAL;
435 	}
436 
437 	return w5100_probe(&spi->dev, ops, priv_size, mac, spi->irq, -EINVAL);
438 }
439 
440 static int w5100_spi_remove(struct spi_device *spi)
441 {
442 	return w5100_remove(&spi->dev);
443 }
444 
445 static const struct spi_device_id w5100_spi_ids[] = {
446 	{ "w5100", W5100 },
447 	{ "w5200", W5200 },
448 	{ "w5500", W5500 },
449 	{}
450 };
451 MODULE_DEVICE_TABLE(spi, w5100_spi_ids);
452 
453 static struct spi_driver w5100_spi_driver = {
454 	.driver		= {
455 		.name	= "w5100",
456 		.pm	= &w5100_pm_ops,
457 	},
458 	.probe		= w5100_spi_probe,
459 	.remove		= w5100_spi_remove,
460 	.id_table	= w5100_spi_ids,
461 };
462 module_spi_driver(w5100_spi_driver);
463 
464 MODULE_DESCRIPTION("WIZnet W5100/W5200/W5500 Ethernet driver for SPI mode");
465 MODULE_AUTHOR("Akinobu Mita <akinobu.mita@gmail.com>");
466 MODULE_LICENSE("GPL");
467