xref: /openbmc/linux/drivers/net/wireless/ti/wlcore/spi.c (revision 612a462a)
1 /*
2  * This file is part of wl1271
3  *
4  * Copyright (C) 2008-2009 Nokia Corporation
5  *
6  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * version 2 as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20  * 02110-1301 USA
21  *
22  */
23 
24 #include <linux/interrupt.h>
25 #include <linux/irq.h>
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/swab.h>
29 #include <linux/crc7.h>
30 #include <linux/spi/spi.h>
31 #include <linux/wl12xx.h>
32 #include <linux/platform_device.h>
33 #include <linux/of_irq.h>
34 #include <linux/regulator/consumer.h>
35 
36 #include "wlcore.h"
37 #include "wl12xx_80211.h"
38 #include "io.h"
39 
40 #define WSPI_CMD_READ                 0x40000000
41 #define WSPI_CMD_WRITE                0x00000000
42 #define WSPI_CMD_FIXED                0x20000000
43 #define WSPI_CMD_BYTE_LENGTH          0x1FFE0000
44 #define WSPI_CMD_BYTE_LENGTH_OFFSET   17
45 #define WSPI_CMD_BYTE_ADDR            0x0001FFFF
46 
47 #define WSPI_INIT_CMD_CRC_LEN       5
48 
49 #define WSPI_INIT_CMD_START         0x00
50 #define WSPI_INIT_CMD_TX            0x40
51 /* the extra bypass bit is sampled by the TNET as '1' */
52 #define WSPI_INIT_CMD_BYPASS_BIT    0x80
53 #define WSPI_INIT_CMD_FIXEDBUSY_LEN 0x07
54 #define WSPI_INIT_CMD_EN_FIXEDBUSY  0x80
55 #define WSPI_INIT_CMD_DIS_FIXEDBUSY 0x00
56 #define WSPI_INIT_CMD_IOD           0x40
57 #define WSPI_INIT_CMD_IP            0x20
58 #define WSPI_INIT_CMD_CS            0x10
59 #define WSPI_INIT_CMD_WS            0x08
60 #define WSPI_INIT_CMD_WSPI          0x01
61 #define WSPI_INIT_CMD_END           0x01
62 
63 #define WSPI_INIT_CMD_LEN           8
64 
65 #define HW_ACCESS_WSPI_FIXED_BUSY_LEN \
66 		((WL1271_BUSY_WORD_LEN - 4) / sizeof(u32))
67 #define HW_ACCESS_WSPI_INIT_CMD_MASK  0
68 
69 /* HW limitation: maximum possible chunk size is 4095 bytes */
70 #define WSPI_MAX_CHUNK_SIZE    4092
71 
72 /*
73  * wl18xx driver aggregation buffer size is (13 * 4K) compared to
74  * (4 * 4K) for wl12xx, so use the larger buffer needed for wl18xx
75  */
76 #define SPI_AGGR_BUFFER_SIZE (13 * SZ_4K)
77 
78 /* Maximum number of SPI write chunks */
79 #define WSPI_MAX_NUM_OF_CHUNKS \
80 	((SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) + 1)
81 
82 static const struct wilink_family_data wl127x_data = {
83 	.name = "wl127x",
84 	.nvs_name = "ti-connectivity/wl127x-nvs.bin",
85 };
86 
87 static const struct wilink_family_data wl128x_data = {
88 	.name = "wl128x",
89 	.nvs_name = "ti-connectivity/wl128x-nvs.bin",
90 };
91 
92 static const struct wilink_family_data wl18xx_data = {
93 	.name = "wl18xx",
94 	.cfg_name = "ti-connectivity/wl18xx-conf.bin",
95 	.nvs_name = "ti-connectivity/wl1271-nvs.bin",
96 };
97 
98 struct wl12xx_spi_glue {
99 	struct device *dev;
100 	struct platform_device *core;
101 	struct regulator *reg; /* Power regulator */
102 };
103 
104 static void wl12xx_spi_reset(struct device *child)
105 {
106 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
107 	u8 *cmd;
108 	struct spi_transfer t;
109 	struct spi_message m;
110 
111 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
112 	if (!cmd) {
113 		dev_err(child->parent,
114 			"could not allocate cmd for spi reset\n");
115 		return;
116 	}
117 
118 	memset(&t, 0, sizeof(t));
119 	spi_message_init(&m);
120 
121 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
122 
123 	t.tx_buf = cmd;
124 	t.len = WSPI_INIT_CMD_LEN;
125 	spi_message_add_tail(&t, &m);
126 
127 	spi_sync(to_spi_device(glue->dev), &m);
128 
129 	kfree(cmd);
130 }
131 
132 static void wl12xx_spi_init(struct device *child)
133 {
134 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
135 	struct spi_transfer t;
136 	struct spi_message m;
137 	struct spi_device *spi = to_spi_device(glue->dev);
138 	u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
139 
140 	if (!cmd) {
141 		dev_err(child->parent,
142 			"could not allocate cmd for spi init\n");
143 		return;
144 	}
145 
146 	memset(&t, 0, sizeof(t));
147 	spi_message_init(&m);
148 
149 	/*
150 	 * Set WSPI_INIT_COMMAND
151 	 * the data is being send from the MSB to LSB
152 	 */
153 	cmd[0] = 0xff;
154 	cmd[1] = 0xff;
155 	cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
156 	cmd[3] = 0;
157 	cmd[4] = 0;
158 	cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
159 	cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
160 
161 	cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
162 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
163 
164 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
165 		cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
166 	else
167 		cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
168 
169 	cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
170 
171 	/*
172 	 * The above is the logical order; it must actually be stored
173 	 * in the buffer byte-swapped.
174 	 */
175 	__swab32s((u32 *)cmd);
176 	__swab32s((u32 *)cmd+1);
177 
178 	t.tx_buf = cmd;
179 	t.len = WSPI_INIT_CMD_LEN;
180 	spi_message_add_tail(&t, &m);
181 
182 	spi_sync(to_spi_device(glue->dev), &m);
183 
184 	/* Send extra clocks with inverted CS (high). this is required
185 	 * by the wilink family in order to successfully enter WSPI mode.
186 	 */
187 	spi->mode ^= SPI_CS_HIGH;
188 	memset(&m, 0, sizeof(m));
189 	spi_message_init(&m);
190 
191 	cmd[0] = 0xff;
192 	cmd[1] = 0xff;
193 	cmd[2] = 0xff;
194 	cmd[3] = 0xff;
195 	__swab32s((u32 *)cmd);
196 
197 	t.tx_buf = cmd;
198 	t.len = 4;
199 	spi_message_add_tail(&t, &m);
200 
201 	spi_sync(to_spi_device(glue->dev), &m);
202 
203 	/* Restore chip select configration to normal */
204 	spi->mode ^= SPI_CS_HIGH;
205 	kfree(cmd);
206 }
207 
208 #define WL1271_BUSY_WORD_TIMEOUT 1000
209 
210 static int wl12xx_spi_read_busy(struct device *child)
211 {
212 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
213 	struct wl1271 *wl = dev_get_drvdata(child);
214 	struct spi_transfer t[1];
215 	struct spi_message m;
216 	u32 *busy_buf;
217 	int num_busy_bytes = 0;
218 
219 	/*
220 	 * Read further busy words from SPI until a non-busy word is
221 	 * encountered, then read the data itself into the buffer.
222 	 */
223 
224 	num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
225 	busy_buf = wl->buffer_busyword;
226 	while (num_busy_bytes) {
227 		num_busy_bytes--;
228 		spi_message_init(&m);
229 		memset(t, 0, sizeof(t));
230 		t[0].rx_buf = busy_buf;
231 		t[0].len = sizeof(u32);
232 		t[0].cs_change = true;
233 		spi_message_add_tail(&t[0], &m);
234 		spi_sync(to_spi_device(glue->dev), &m);
235 
236 		if (*busy_buf & 0x1)
237 			return 0;
238 	}
239 
240 	/* The SPI bus is unresponsive, the read failed. */
241 	dev_err(child->parent, "SPI read busy-word timeout!\n");
242 	return -ETIMEDOUT;
243 }
244 
245 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
246 					    void *buf, size_t len, bool fixed)
247 {
248 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
249 	struct wl1271 *wl = dev_get_drvdata(child);
250 	struct spi_transfer t[2];
251 	struct spi_message m;
252 	u32 *busy_buf;
253 	u32 *cmd;
254 	u32 chunk_len;
255 
256 	while (len > 0) {
257 		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
258 
259 		cmd = &wl->buffer_cmd;
260 		busy_buf = wl->buffer_busyword;
261 
262 		*cmd = 0;
263 		*cmd |= WSPI_CMD_READ;
264 		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
265 			WSPI_CMD_BYTE_LENGTH;
266 		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
267 
268 		if (fixed)
269 			*cmd |= WSPI_CMD_FIXED;
270 
271 		spi_message_init(&m);
272 		memset(t, 0, sizeof(t));
273 
274 		t[0].tx_buf = cmd;
275 		t[0].len = 4;
276 		t[0].cs_change = true;
277 		spi_message_add_tail(&t[0], &m);
278 
279 		/* Busy and non busy words read */
280 		t[1].rx_buf = busy_buf;
281 		t[1].len = WL1271_BUSY_WORD_LEN;
282 		t[1].cs_change = true;
283 		spi_message_add_tail(&t[1], &m);
284 
285 		spi_sync(to_spi_device(glue->dev), &m);
286 
287 		if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
288 		    wl12xx_spi_read_busy(child)) {
289 			memset(buf, 0, chunk_len);
290 			return 0;
291 		}
292 
293 		spi_message_init(&m);
294 		memset(t, 0, sizeof(t));
295 
296 		t[0].rx_buf = buf;
297 		t[0].len = chunk_len;
298 		t[0].cs_change = true;
299 		spi_message_add_tail(&t[0], &m);
300 
301 		spi_sync(to_spi_device(glue->dev), &m);
302 
303 		if (!fixed)
304 			addr += chunk_len;
305 		buf += chunk_len;
306 		len -= chunk_len;
307 	}
308 
309 	return 0;
310 }
311 
312 static int __wl12xx_spi_raw_write(struct device *child, int addr,
313 				  void *buf, size_t len, bool fixed)
314 {
315 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
316 	struct spi_transfer *t;
317 	struct spi_message m;
318 	u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
319 	u32 *cmd;
320 	u32 chunk_len;
321 	int i;
322 
323 	/* SPI write buffers - 2 for each chunk */
324 	t = kzalloc(sizeof(*t) * 2 * WSPI_MAX_NUM_OF_CHUNKS, GFP_KERNEL);
325 	if (!t)
326 		return -ENOMEM;
327 
328 	WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
329 
330 	spi_message_init(&m);
331 
332 	cmd = &commands[0];
333 	i = 0;
334 	while (len > 0) {
335 		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
336 
337 		*cmd = 0;
338 		*cmd |= WSPI_CMD_WRITE;
339 		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
340 			WSPI_CMD_BYTE_LENGTH;
341 		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
342 
343 		if (fixed)
344 			*cmd |= WSPI_CMD_FIXED;
345 
346 		t[i].tx_buf = cmd;
347 		t[i].len = sizeof(*cmd);
348 		spi_message_add_tail(&t[i++], &m);
349 
350 		t[i].tx_buf = buf;
351 		t[i].len = chunk_len;
352 		spi_message_add_tail(&t[i++], &m);
353 
354 		if (!fixed)
355 			addr += chunk_len;
356 		buf += chunk_len;
357 		len -= chunk_len;
358 		cmd++;
359 	}
360 
361 	spi_sync(to_spi_device(glue->dev), &m);
362 
363 	kfree(t);
364 	return 0;
365 }
366 
367 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
368 					     void *buf, size_t len, bool fixed)
369 {
370 	/* The ELP wakeup write may fail the first time due to internal
371 	 * hardware latency. It is safer to send the wakeup command twice to
372 	 * avoid unexpected failures.
373 	 */
374 	if (addr == HW_ACCESS_ELP_CTRL_REG)
375 		__wl12xx_spi_raw_write(child, addr, buf, len, fixed);
376 
377 	return __wl12xx_spi_raw_write(child, addr, buf, len, fixed);
378 }
379 
380 /**
381  * wl12xx_spi_set_power - power on/off the wl12xx unit
382  * @child: wl12xx device handle.
383  * @enable: true/false to power on/off the unit.
384  *
385  * use the WiFi enable regulator to enable/disable the WiFi unit.
386  */
387 static int wl12xx_spi_set_power(struct device *child, bool enable)
388 {
389 	int ret = 0;
390 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
391 
392 	WARN_ON(!glue->reg);
393 
394 	/* Update regulator state */
395 	if (enable) {
396 		ret = regulator_enable(glue->reg);
397 		if (ret)
398 			dev_err(child, "Power enable failure\n");
399 	} else {
400 		ret =  regulator_disable(glue->reg);
401 		if (ret)
402 			dev_err(child, "Power disable failure\n");
403 	}
404 
405 	return ret;
406 }
407 
408 /**
409  * wl12xx_spi_set_block_size
410  *
411  * This function is not needed for spi mode, but need to be present.
412  * Without it defined the wlcore fallback to use the wrong packet
413  * allignment on tx.
414  */
415 static void wl12xx_spi_set_block_size(struct device *child,
416 				      unsigned int blksz)
417 {
418 }
419 
420 static struct wl1271_if_operations spi_ops = {
421 	.read		= wl12xx_spi_raw_read,
422 	.write		= wl12xx_spi_raw_write,
423 	.reset		= wl12xx_spi_reset,
424 	.init		= wl12xx_spi_init,
425 	.power		= wl12xx_spi_set_power,
426 	.set_block_size = wl12xx_spi_set_block_size,
427 };
428 
429 static const struct of_device_id wlcore_spi_of_match_table[] = {
430 	{ .compatible = "ti,wl1271", .data = &wl127x_data},
431 	{ .compatible = "ti,wl1273", .data = &wl127x_data},
432 	{ .compatible = "ti,wl1281", .data = &wl128x_data},
433 	{ .compatible = "ti,wl1283", .data = &wl128x_data},
434 	{ .compatible = "ti,wl1285", .data = &wl128x_data},
435 	{ .compatible = "ti,wl1801", .data = &wl18xx_data},
436 	{ .compatible = "ti,wl1805", .data = &wl18xx_data},
437 	{ .compatible = "ti,wl1807", .data = &wl18xx_data},
438 	{ .compatible = "ti,wl1831", .data = &wl18xx_data},
439 	{ .compatible = "ti,wl1835", .data = &wl18xx_data},
440 	{ .compatible = "ti,wl1837", .data = &wl18xx_data},
441 	{ }
442 };
443 MODULE_DEVICE_TABLE(of, wlcore_spi_of_match_table);
444 
445 /**
446  * wlcore_probe_of - DT node parsing.
447  * @spi: SPI slave device parameters.
448  * @res: resource parameters.
449  * @glue: wl12xx SPI bus to slave device glue parameters.
450  * @pdev_data: wlcore device parameters
451  */
452 static int wlcore_probe_of(struct spi_device *spi, struct wl12xx_spi_glue *glue,
453 			   struct wlcore_platdev_data *pdev_data)
454 {
455 	struct device_node *dt_node = spi->dev.of_node;
456 	const struct of_device_id *of_id;
457 
458 	of_id = of_match_node(wlcore_spi_of_match_table, dt_node);
459 	if (!of_id)
460 		return -ENODEV;
461 
462 	pdev_data->family = of_id->data;
463 	dev_info(&spi->dev, "selected chip family is %s\n",
464 		 pdev_data->family->name);
465 
466 	if (of_find_property(dt_node, "clock-xtal", NULL))
467 		pdev_data->ref_clock_xtal = true;
468 
469 	/* optional clock frequency params */
470 	of_property_read_u32(dt_node, "ref-clock-frequency",
471 			     &pdev_data->ref_clock_freq);
472 	of_property_read_u32(dt_node, "tcxo-clock-frequency",
473 			     &pdev_data->tcxo_clock_freq);
474 
475 	return 0;
476 }
477 
478 static int wl1271_probe(struct spi_device *spi)
479 {
480 	struct wl12xx_spi_glue *glue;
481 	struct wlcore_platdev_data *pdev_data;
482 	struct resource res[1];
483 	int ret;
484 
485 	pdev_data = devm_kzalloc(&spi->dev, sizeof(*pdev_data), GFP_KERNEL);
486 	if (!pdev_data)
487 		return -ENOMEM;
488 
489 	pdev_data->if_ops = &spi_ops;
490 
491 	glue = devm_kzalloc(&spi->dev, sizeof(*glue), GFP_KERNEL);
492 	if (!glue) {
493 		dev_err(&spi->dev, "can't allocate glue\n");
494 		return -ENOMEM;
495 	}
496 
497 	glue->dev = &spi->dev;
498 
499 	spi_set_drvdata(spi, glue);
500 
501 	/* This is the only SPI value that we need to set here, the rest
502 	 * comes from the board-peripherals file */
503 	spi->bits_per_word = 32;
504 
505 	glue->reg = devm_regulator_get(&spi->dev, "vwlan");
506 	if (PTR_ERR(glue->reg) == -EPROBE_DEFER)
507 		return -EPROBE_DEFER;
508 	if (IS_ERR(glue->reg)) {
509 		dev_err(glue->dev, "can't get regulator\n");
510 		return PTR_ERR(glue->reg);
511 	}
512 
513 	ret = wlcore_probe_of(spi, glue, pdev_data);
514 	if (ret) {
515 		dev_err(glue->dev,
516 			"can't get device tree parameters (%d)\n", ret);
517 		return ret;
518 	}
519 
520 	ret = spi_setup(spi);
521 	if (ret < 0) {
522 		dev_err(glue->dev, "spi_setup failed\n");
523 		return ret;
524 	}
525 
526 	glue->core = platform_device_alloc(pdev_data->family->name,
527 					   PLATFORM_DEVID_AUTO);
528 	if (!glue->core) {
529 		dev_err(glue->dev, "can't allocate platform_device\n");
530 		return -ENOMEM;
531 	}
532 
533 	glue->core->dev.parent = &spi->dev;
534 
535 	memset(res, 0x00, sizeof(res));
536 
537 	res[0].start = spi->irq;
538 	res[0].flags = IORESOURCE_IRQ | irq_get_trigger_type(spi->irq);
539 	res[0].name = "irq";
540 
541 	ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
542 	if (ret) {
543 		dev_err(glue->dev, "can't add resources\n");
544 		goto out_dev_put;
545 	}
546 
547 	ret = platform_device_add_data(glue->core, pdev_data,
548 				       sizeof(*pdev_data));
549 	if (ret) {
550 		dev_err(glue->dev, "can't add platform data\n");
551 		goto out_dev_put;
552 	}
553 
554 	ret = platform_device_add(glue->core);
555 	if (ret) {
556 		dev_err(glue->dev, "can't register platform device\n");
557 		goto out_dev_put;
558 	}
559 
560 	return 0;
561 
562 out_dev_put:
563 	platform_device_put(glue->core);
564 	return ret;
565 }
566 
567 static int wl1271_remove(struct spi_device *spi)
568 {
569 	struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
570 
571 	platform_device_unregister(glue->core);
572 
573 	return 0;
574 }
575 
576 static struct spi_driver wl1271_spi_driver = {
577 	.driver = {
578 		.name		= "wl1271_spi",
579 		.of_match_table = of_match_ptr(wlcore_spi_of_match_table),
580 	},
581 
582 	.probe		= wl1271_probe,
583 	.remove		= wl1271_remove,
584 };
585 
586 module_spi_driver(wl1271_spi_driver);
587 MODULE_LICENSE("GPL");
588 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
589 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
590 MODULE_ALIAS("spi:wl1271");
591