xref: /openbmc/linux/drivers/net/wireless/ti/wlcore/spi.c (revision c8dbaa22)
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 };
96 
97 struct wl12xx_spi_glue {
98 	struct device *dev;
99 	struct platform_device *core;
100 	struct regulator *reg; /* Power regulator */
101 };
102 
103 static void wl12xx_spi_reset(struct device *child)
104 {
105 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
106 	u8 *cmd;
107 	struct spi_transfer t;
108 	struct spi_message m;
109 
110 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
111 	if (!cmd) {
112 		dev_err(child->parent,
113 			"could not allocate cmd for spi reset\n");
114 		return;
115 	}
116 
117 	memset(&t, 0, sizeof(t));
118 	spi_message_init(&m);
119 
120 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
121 
122 	t.tx_buf = cmd;
123 	t.len = WSPI_INIT_CMD_LEN;
124 	spi_message_add_tail(&t, &m);
125 
126 	spi_sync(to_spi_device(glue->dev), &m);
127 
128 	kfree(cmd);
129 }
130 
131 static void wl12xx_spi_init(struct device *child)
132 {
133 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
134 	struct spi_transfer t;
135 	struct spi_message m;
136 	struct spi_device *spi = to_spi_device(glue->dev);
137 	u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
138 
139 	if (!cmd) {
140 		dev_err(child->parent,
141 			"could not allocate cmd for spi init\n");
142 		return;
143 	}
144 
145 	memset(&t, 0, sizeof(t));
146 	spi_message_init(&m);
147 
148 	/*
149 	 * Set WSPI_INIT_COMMAND
150 	 * the data is being send from the MSB to LSB
151 	 */
152 	cmd[0] = 0xff;
153 	cmd[1] = 0xff;
154 	cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
155 	cmd[3] = 0;
156 	cmd[4] = 0;
157 	cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
158 	cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
159 
160 	cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
161 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
162 
163 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
164 		cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
165 	else
166 		cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
167 
168 	cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
169 
170 	/*
171 	 * The above is the logical order; it must actually be stored
172 	 * in the buffer byte-swapped.
173 	 */
174 	__swab32s((u32 *)cmd);
175 	__swab32s((u32 *)cmd+1);
176 
177 	t.tx_buf = cmd;
178 	t.len = WSPI_INIT_CMD_LEN;
179 	spi_message_add_tail(&t, &m);
180 
181 	spi_sync(to_spi_device(glue->dev), &m);
182 
183 	/* Send extra clocks with inverted CS (high). this is required
184 	 * by the wilink family in order to successfully enter WSPI mode.
185 	 */
186 	spi->mode ^= SPI_CS_HIGH;
187 	memset(&m, 0, sizeof(m));
188 	spi_message_init(&m);
189 
190 	cmd[0] = 0xff;
191 	cmd[1] = 0xff;
192 	cmd[2] = 0xff;
193 	cmd[3] = 0xff;
194 	__swab32s((u32 *)cmd);
195 
196 	t.tx_buf = cmd;
197 	t.len = 4;
198 	spi_message_add_tail(&t, &m);
199 
200 	spi_sync(to_spi_device(glue->dev), &m);
201 
202 	/* Restore chip select configration to normal */
203 	spi->mode ^= SPI_CS_HIGH;
204 	kfree(cmd);
205 }
206 
207 #define WL1271_BUSY_WORD_TIMEOUT 1000
208 
209 static int wl12xx_spi_read_busy(struct device *child)
210 {
211 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
212 	struct wl1271 *wl = dev_get_drvdata(child);
213 	struct spi_transfer t[1];
214 	struct spi_message m;
215 	u32 *busy_buf;
216 	int num_busy_bytes = 0;
217 
218 	/*
219 	 * Read further busy words from SPI until a non-busy word is
220 	 * encountered, then read the data itself into the buffer.
221 	 */
222 
223 	num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
224 	busy_buf = wl->buffer_busyword;
225 	while (num_busy_bytes) {
226 		num_busy_bytes--;
227 		spi_message_init(&m);
228 		memset(t, 0, sizeof(t));
229 		t[0].rx_buf = busy_buf;
230 		t[0].len = sizeof(u32);
231 		t[0].cs_change = true;
232 		spi_message_add_tail(&t[0], &m);
233 		spi_sync(to_spi_device(glue->dev), &m);
234 
235 		if (*busy_buf & 0x1)
236 			return 0;
237 	}
238 
239 	/* The SPI bus is unresponsive, the read failed. */
240 	dev_err(child->parent, "SPI read busy-word timeout!\n");
241 	return -ETIMEDOUT;
242 }
243 
244 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
245 					    void *buf, size_t len, bool fixed)
246 {
247 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
248 	struct wl1271 *wl = dev_get_drvdata(child);
249 	struct spi_transfer t[2];
250 	struct spi_message m;
251 	u32 *busy_buf;
252 	u32 *cmd;
253 	u32 chunk_len;
254 
255 	while (len > 0) {
256 		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
257 
258 		cmd = &wl->buffer_cmd;
259 		busy_buf = wl->buffer_busyword;
260 
261 		*cmd = 0;
262 		*cmd |= WSPI_CMD_READ;
263 		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
264 			WSPI_CMD_BYTE_LENGTH;
265 		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
266 
267 		if (fixed)
268 			*cmd |= WSPI_CMD_FIXED;
269 
270 		spi_message_init(&m);
271 		memset(t, 0, sizeof(t));
272 
273 		t[0].tx_buf = cmd;
274 		t[0].len = 4;
275 		t[0].cs_change = true;
276 		spi_message_add_tail(&t[0], &m);
277 
278 		/* Busy and non busy words read */
279 		t[1].rx_buf = busy_buf;
280 		t[1].len = WL1271_BUSY_WORD_LEN;
281 		t[1].cs_change = true;
282 		spi_message_add_tail(&t[1], &m);
283 
284 		spi_sync(to_spi_device(glue->dev), &m);
285 
286 		if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
287 		    wl12xx_spi_read_busy(child)) {
288 			memset(buf, 0, chunk_len);
289 			return 0;
290 		}
291 
292 		spi_message_init(&m);
293 		memset(t, 0, sizeof(t));
294 
295 		t[0].rx_buf = buf;
296 		t[0].len = chunk_len;
297 		t[0].cs_change = true;
298 		spi_message_add_tail(&t[0], &m);
299 
300 		spi_sync(to_spi_device(glue->dev), &m);
301 
302 		if (!fixed)
303 			addr += chunk_len;
304 		buf += chunk_len;
305 		len -= chunk_len;
306 	}
307 
308 	return 0;
309 }
310 
311 static int __wl12xx_spi_raw_write(struct device *child, int addr,
312 				  void *buf, size_t len, bool fixed)
313 {
314 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
315 	struct spi_transfer *t;
316 	struct spi_message m;
317 	u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
318 	u32 *cmd;
319 	u32 chunk_len;
320 	int i;
321 
322 	/* SPI write buffers - 2 for each chunk */
323 	t = kzalloc(sizeof(*t) * 2 * WSPI_MAX_NUM_OF_CHUNKS, GFP_KERNEL);
324 	if (!t)
325 		return -ENOMEM;
326 
327 	WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
328 
329 	spi_message_init(&m);
330 
331 	cmd = &commands[0];
332 	i = 0;
333 	while (len > 0) {
334 		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
335 
336 		*cmd = 0;
337 		*cmd |= WSPI_CMD_WRITE;
338 		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
339 			WSPI_CMD_BYTE_LENGTH;
340 		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
341 
342 		if (fixed)
343 			*cmd |= WSPI_CMD_FIXED;
344 
345 		t[i].tx_buf = cmd;
346 		t[i].len = sizeof(*cmd);
347 		spi_message_add_tail(&t[i++], &m);
348 
349 		t[i].tx_buf = buf;
350 		t[i].len = chunk_len;
351 		spi_message_add_tail(&t[i++], &m);
352 
353 		if (!fixed)
354 			addr += chunk_len;
355 		buf += chunk_len;
356 		len -= chunk_len;
357 		cmd++;
358 	}
359 
360 	spi_sync(to_spi_device(glue->dev), &m);
361 
362 	kfree(t);
363 	return 0;
364 }
365 
366 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
367 					     void *buf, size_t len, bool fixed)
368 {
369 	/* The ELP wakeup write may fail the first time due to internal
370 	 * hardware latency. It is safer to send the wakeup command twice to
371 	 * avoid unexpected failures.
372 	 */
373 	if (addr == HW_ACCESS_ELP_CTRL_REG)
374 		__wl12xx_spi_raw_write(child, addr, buf, len, fixed);
375 
376 	return __wl12xx_spi_raw_write(child, addr, buf, len, fixed);
377 }
378 
379 /**
380  * wl12xx_spi_set_power - power on/off the wl12xx unit
381  * @child: wl12xx device handle.
382  * @enable: true/false to power on/off the unit.
383  *
384  * use the WiFi enable regulator to enable/disable the WiFi unit.
385  */
386 static int wl12xx_spi_set_power(struct device *child, bool enable)
387 {
388 	int ret = 0;
389 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
390 
391 	WARN_ON(!glue->reg);
392 
393 	/* Update regulator state */
394 	if (enable) {
395 		ret = regulator_enable(glue->reg);
396 		if (ret)
397 			dev_err(child, "Power enable failure\n");
398 	} else {
399 		ret =  regulator_disable(glue->reg);
400 		if (ret)
401 			dev_err(child, "Power disable failure\n");
402 	}
403 
404 	return ret;
405 }
406 
407 /**
408  * wl12xx_spi_set_block_size
409  *
410  * This function is not needed for spi mode, but need to be present.
411  * Without it defined the wlcore fallback to use the wrong packet
412  * allignment on tx.
413  */
414 static void wl12xx_spi_set_block_size(struct device *child,
415 				      unsigned int blksz)
416 {
417 }
418 
419 static struct wl1271_if_operations spi_ops = {
420 	.read		= wl12xx_spi_raw_read,
421 	.write		= wl12xx_spi_raw_write,
422 	.reset		= wl12xx_spi_reset,
423 	.init		= wl12xx_spi_init,
424 	.power		= wl12xx_spi_set_power,
425 	.set_block_size = wl12xx_spi_set_block_size,
426 };
427 
428 static const struct of_device_id wlcore_spi_of_match_table[] = {
429 	{ .compatible = "ti,wl1271", .data = &wl127x_data},
430 	{ .compatible = "ti,wl1273", .data = &wl127x_data},
431 	{ .compatible = "ti,wl1281", .data = &wl128x_data},
432 	{ .compatible = "ti,wl1283", .data = &wl128x_data},
433 	{ .compatible = "ti,wl1285", .data = &wl128x_data},
434 	{ .compatible = "ti,wl1801", .data = &wl18xx_data},
435 	{ .compatible = "ti,wl1805", .data = &wl18xx_data},
436 	{ .compatible = "ti,wl1807", .data = &wl18xx_data},
437 	{ .compatible = "ti,wl1831", .data = &wl18xx_data},
438 	{ .compatible = "ti,wl1835", .data = &wl18xx_data},
439 	{ .compatible = "ti,wl1837", .data = &wl18xx_data},
440 	{ }
441 };
442 MODULE_DEVICE_TABLE(of, wlcore_spi_of_match_table);
443 
444 /**
445  * wlcore_probe_of - DT node parsing.
446  * @spi: SPI slave device parameters.
447  * @res: resource parameters.
448  * @glue: wl12xx SPI bus to slave device glue parameters.
449  * @pdev_data: wlcore device parameters
450  */
451 static int wlcore_probe_of(struct spi_device *spi, struct wl12xx_spi_glue *glue,
452 			   struct wlcore_platdev_data *pdev_data)
453 {
454 	struct device_node *dt_node = spi->dev.of_node;
455 	const struct of_device_id *of_id;
456 
457 	of_id = of_match_node(wlcore_spi_of_match_table, dt_node);
458 	if (!of_id)
459 		return -ENODEV;
460 
461 	pdev_data->family = of_id->data;
462 	dev_info(&spi->dev, "selected chip family is %s\n",
463 		 pdev_data->family->name);
464 
465 	if (of_find_property(dt_node, "clock-xtal", NULL))
466 		pdev_data->ref_clock_xtal = true;
467 
468 	/* optional clock frequency params */
469 	of_property_read_u32(dt_node, "ref-clock-frequency",
470 			     &pdev_data->ref_clock_freq);
471 	of_property_read_u32(dt_node, "tcxo-clock-frequency",
472 			     &pdev_data->tcxo_clock_freq);
473 
474 	return 0;
475 }
476 
477 static int wl1271_probe(struct spi_device *spi)
478 {
479 	struct wl12xx_spi_glue *glue;
480 	struct wlcore_platdev_data *pdev_data;
481 	struct resource res[1];
482 	int ret;
483 
484 	pdev_data = devm_kzalloc(&spi->dev, sizeof(*pdev_data), GFP_KERNEL);
485 	if (!pdev_data)
486 		return -ENOMEM;
487 
488 	pdev_data->if_ops = &spi_ops;
489 
490 	glue = devm_kzalloc(&spi->dev, sizeof(*glue), GFP_KERNEL);
491 	if (!glue) {
492 		dev_err(&spi->dev, "can't allocate glue\n");
493 		return -ENOMEM;
494 	}
495 
496 	glue->dev = &spi->dev;
497 
498 	spi_set_drvdata(spi, glue);
499 
500 	/* This is the only SPI value that we need to set here, the rest
501 	 * comes from the board-peripherals file */
502 	spi->bits_per_word = 32;
503 
504 	glue->reg = devm_regulator_get(&spi->dev, "vwlan");
505 	if (PTR_ERR(glue->reg) == -EPROBE_DEFER)
506 		return -EPROBE_DEFER;
507 	if (IS_ERR(glue->reg)) {
508 		dev_err(glue->dev, "can't get regulator\n");
509 		return PTR_ERR(glue->reg);
510 	}
511 
512 	ret = wlcore_probe_of(spi, glue, pdev_data);
513 	if (ret) {
514 		dev_err(glue->dev,
515 			"can't get device tree parameters (%d)\n", ret);
516 		return ret;
517 	}
518 
519 	ret = spi_setup(spi);
520 	if (ret < 0) {
521 		dev_err(glue->dev, "spi_setup failed\n");
522 		return ret;
523 	}
524 
525 	glue->core = platform_device_alloc(pdev_data->family->name,
526 					   PLATFORM_DEVID_AUTO);
527 	if (!glue->core) {
528 		dev_err(glue->dev, "can't allocate platform_device\n");
529 		return -ENOMEM;
530 	}
531 
532 	glue->core->dev.parent = &spi->dev;
533 
534 	memset(res, 0x00, sizeof(res));
535 
536 	res[0].start = spi->irq;
537 	res[0].flags = IORESOURCE_IRQ | irq_get_trigger_type(spi->irq);
538 	res[0].name = "irq";
539 
540 	ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
541 	if (ret) {
542 		dev_err(glue->dev, "can't add resources\n");
543 		goto out_dev_put;
544 	}
545 
546 	ret = platform_device_add_data(glue->core, pdev_data,
547 				       sizeof(*pdev_data));
548 	if (ret) {
549 		dev_err(glue->dev, "can't add platform data\n");
550 		goto out_dev_put;
551 	}
552 
553 	ret = platform_device_add(glue->core);
554 	if (ret) {
555 		dev_err(glue->dev, "can't register platform device\n");
556 		goto out_dev_put;
557 	}
558 
559 	return 0;
560 
561 out_dev_put:
562 	platform_device_put(glue->core);
563 	return ret;
564 }
565 
566 static int wl1271_remove(struct spi_device *spi)
567 {
568 	struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
569 
570 	platform_device_unregister(glue->core);
571 
572 	return 0;
573 }
574 
575 static struct spi_driver wl1271_spi_driver = {
576 	.driver = {
577 		.name		= "wl1271_spi",
578 		.of_match_table = of_match_ptr(wlcore_spi_of_match_table),
579 	},
580 
581 	.probe		= wl1271_probe,
582 	.remove		= wl1271_remove,
583 };
584 
585 module_spi_driver(wl1271_spi_driver);
586 MODULE_LICENSE("GPL");
587 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
588 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
589 MODULE_ALIAS("spi:wl1271");
590