xref: /openbmc/linux/drivers/net/wireless/ti/wlcore/spi.c (revision 404e077a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * This file is part of wl1271
4  *
5  * Copyright (C) 2008-2009 Nokia Corporation
6  *
7  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
8  */
9 
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/swab.h>
15 #include <linux/crc7.h>
16 #include <linux/spi/spi.h>
17 #include <linux/platform_device.h>
18 #include <linux/of_irq.h>
19 #include <linux/regulator/consumer.h>
20 
21 #include "wlcore.h"
22 #include "wl12xx_80211.h"
23 #include "io.h"
24 
25 #define WSPI_CMD_READ                 0x40000000
26 #define WSPI_CMD_WRITE                0x00000000
27 #define WSPI_CMD_FIXED                0x20000000
28 #define WSPI_CMD_BYTE_LENGTH          0x1FFE0000
29 #define WSPI_CMD_BYTE_LENGTH_OFFSET   17
30 #define WSPI_CMD_BYTE_ADDR            0x0001FFFF
31 
32 #define WSPI_INIT_CMD_CRC_LEN       5
33 
34 #define WSPI_INIT_CMD_START         0x00
35 #define WSPI_INIT_CMD_TX            0x40
36 /* the extra bypass bit is sampled by the TNET as '1' */
37 #define WSPI_INIT_CMD_BYPASS_BIT    0x80
38 #define WSPI_INIT_CMD_FIXEDBUSY_LEN 0x07
39 #define WSPI_INIT_CMD_EN_FIXEDBUSY  0x80
40 #define WSPI_INIT_CMD_DIS_FIXEDBUSY 0x00
41 #define WSPI_INIT_CMD_IOD           0x40
42 #define WSPI_INIT_CMD_IP            0x20
43 #define WSPI_INIT_CMD_CS            0x10
44 #define WSPI_INIT_CMD_WS            0x08
45 #define WSPI_INIT_CMD_WSPI          0x01
46 #define WSPI_INIT_CMD_END           0x01
47 
48 #define WSPI_INIT_CMD_LEN           8
49 
50 #define HW_ACCESS_WSPI_FIXED_BUSY_LEN \
51 		((WL1271_BUSY_WORD_LEN - 4) / sizeof(u32))
52 #define HW_ACCESS_WSPI_INIT_CMD_MASK  0
53 
54 /* HW limitation: maximum possible chunk size is 4095 bytes */
55 #define WSPI_MAX_CHUNK_SIZE    4092
56 
57 /*
58  * wl18xx driver aggregation buffer size is (13 * 4K) compared to
59  * (4 * 4K) for wl12xx, so use the larger buffer needed for wl18xx
60  */
61 #define SPI_AGGR_BUFFER_SIZE (13 * SZ_4K)
62 
63 /* Maximum number of SPI write chunks */
64 #define WSPI_MAX_NUM_OF_CHUNKS \
65 	((SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) + 1)
66 
67 static const struct wilink_family_data wl127x_data = {
68 	.name = "wl127x",
69 	.nvs_name = "ti-connectivity/wl127x-nvs.bin",
70 };
71 
72 static const struct wilink_family_data wl128x_data = {
73 	.name = "wl128x",
74 	.nvs_name = "ti-connectivity/wl128x-nvs.bin",
75 };
76 
77 static const struct wilink_family_data wl18xx_data = {
78 	.name = "wl18xx",
79 	.cfg_name = "ti-connectivity/wl18xx-conf.bin",
80 	.nvs_name = "ti-connectivity/wl1271-nvs.bin",
81 };
82 
83 struct wl12xx_spi_glue {
84 	struct device *dev;
85 	struct platform_device *core;
86 	struct regulator *reg; /* Power regulator */
87 };
88 
89 static void wl12xx_spi_reset(struct device *child)
90 {
91 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
92 	u8 *cmd;
93 	struct spi_transfer t;
94 	struct spi_message m;
95 
96 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
97 	if (!cmd) {
98 		dev_err(child->parent,
99 			"could not allocate cmd for spi reset\n");
100 		return;
101 	}
102 
103 	memset(&t, 0, sizeof(t));
104 	spi_message_init(&m);
105 
106 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
107 
108 	t.tx_buf = cmd;
109 	t.len = WSPI_INIT_CMD_LEN;
110 	spi_message_add_tail(&t, &m);
111 
112 	spi_sync(to_spi_device(glue->dev), &m);
113 
114 	kfree(cmd);
115 }
116 
117 static void wl12xx_spi_init(struct device *child)
118 {
119 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
120 	struct spi_transfer t;
121 	struct spi_message m;
122 	struct spi_device *spi = to_spi_device(glue->dev);
123 	u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
124 
125 	if (!cmd) {
126 		dev_err(child->parent,
127 			"could not allocate cmd for spi init\n");
128 		return;
129 	}
130 
131 	memset(&t, 0, sizeof(t));
132 	spi_message_init(&m);
133 
134 	/*
135 	 * Set WSPI_INIT_COMMAND
136 	 * the data is being send from the MSB to LSB
137 	 */
138 	cmd[0] = 0xff;
139 	cmd[1] = 0xff;
140 	cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
141 	cmd[3] = 0;
142 	cmd[4] = 0;
143 	cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
144 	cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
145 
146 	cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
147 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
148 
149 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
150 		cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
151 	else
152 		cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
153 
154 	cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
155 
156 	/*
157 	 * The above is the logical order; it must actually be stored
158 	 * in the buffer byte-swapped.
159 	 */
160 	__swab32s((u32 *)cmd);
161 	__swab32s((u32 *)cmd+1);
162 
163 	t.tx_buf = cmd;
164 	t.len = WSPI_INIT_CMD_LEN;
165 	spi_message_add_tail(&t, &m);
166 
167 	spi_sync(to_spi_device(glue->dev), &m);
168 
169 	/* Send extra clocks with inverted CS (high). this is required
170 	 * by the wilink family in order to successfully enter WSPI mode.
171 	 */
172 	spi->mode ^= SPI_CS_HIGH;
173 	memset(&m, 0, sizeof(m));
174 	spi_message_init(&m);
175 
176 	cmd[0] = 0xff;
177 	cmd[1] = 0xff;
178 	cmd[2] = 0xff;
179 	cmd[3] = 0xff;
180 	__swab32s((u32 *)cmd);
181 
182 	t.tx_buf = cmd;
183 	t.len = 4;
184 	spi_message_add_tail(&t, &m);
185 
186 	spi_sync(to_spi_device(glue->dev), &m);
187 
188 	/* Restore chip select configuration to normal */
189 	spi->mode ^= SPI_CS_HIGH;
190 	kfree(cmd);
191 }
192 
193 #define WL1271_BUSY_WORD_TIMEOUT 1000
194 
195 static int wl12xx_spi_read_busy(struct device *child)
196 {
197 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
198 	struct wl1271 *wl = dev_get_drvdata(child);
199 	struct spi_transfer t[1];
200 	struct spi_message m;
201 	u32 *busy_buf;
202 	int num_busy_bytes = 0;
203 
204 	/*
205 	 * Read further busy words from SPI until a non-busy word is
206 	 * encountered, then read the data itself into the buffer.
207 	 */
208 
209 	num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
210 	busy_buf = wl->buffer_busyword;
211 	while (num_busy_bytes) {
212 		num_busy_bytes--;
213 		spi_message_init(&m);
214 		memset(t, 0, sizeof(t));
215 		t[0].rx_buf = busy_buf;
216 		t[0].len = sizeof(u32);
217 		t[0].cs_change = true;
218 		spi_message_add_tail(&t[0], &m);
219 		spi_sync(to_spi_device(glue->dev), &m);
220 
221 		if (*busy_buf & 0x1)
222 			return 0;
223 	}
224 
225 	/* The SPI bus is unresponsive, the read failed. */
226 	dev_err(child->parent, "SPI read busy-word timeout!\n");
227 	return -ETIMEDOUT;
228 }
229 
230 static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
231 					    void *buf, size_t len, bool fixed)
232 {
233 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
234 	struct wl1271 *wl = dev_get_drvdata(child);
235 	struct spi_transfer t[2];
236 	struct spi_message m;
237 	u32 *busy_buf;
238 	u32 *cmd;
239 	u32 chunk_len;
240 
241 	while (len > 0) {
242 		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
243 
244 		cmd = &wl->buffer_cmd;
245 		busy_buf = wl->buffer_busyword;
246 
247 		*cmd = 0;
248 		*cmd |= WSPI_CMD_READ;
249 		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
250 			WSPI_CMD_BYTE_LENGTH;
251 		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
252 
253 		if (fixed)
254 			*cmd |= WSPI_CMD_FIXED;
255 
256 		spi_message_init(&m);
257 		memset(t, 0, sizeof(t));
258 
259 		t[0].tx_buf = cmd;
260 		t[0].len = 4;
261 		t[0].cs_change = true;
262 		spi_message_add_tail(&t[0], &m);
263 
264 		/* Busy and non busy words read */
265 		t[1].rx_buf = busy_buf;
266 		t[1].len = WL1271_BUSY_WORD_LEN;
267 		t[1].cs_change = true;
268 		spi_message_add_tail(&t[1], &m);
269 
270 		spi_sync(to_spi_device(glue->dev), &m);
271 
272 		if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
273 		    wl12xx_spi_read_busy(child)) {
274 			memset(buf, 0, chunk_len);
275 			return 0;
276 		}
277 
278 		spi_message_init(&m);
279 		memset(t, 0, sizeof(t));
280 
281 		t[0].rx_buf = buf;
282 		t[0].len = chunk_len;
283 		t[0].cs_change = true;
284 		spi_message_add_tail(&t[0], &m);
285 
286 		spi_sync(to_spi_device(glue->dev), &m);
287 
288 		if (!fixed)
289 			addr += chunk_len;
290 		buf += chunk_len;
291 		len -= chunk_len;
292 	}
293 
294 	return 0;
295 }
296 
297 static int __wl12xx_spi_raw_write(struct device *child, int addr,
298 				  void *buf, size_t len, bool fixed)
299 {
300 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
301 	struct spi_transfer *t;
302 	struct spi_message m;
303 	u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
304 	u32 *cmd;
305 	u32 chunk_len;
306 	int i;
307 
308 	/* SPI write buffers - 2 for each chunk */
309 	t = kzalloc(sizeof(*t) * 2 * WSPI_MAX_NUM_OF_CHUNKS, GFP_KERNEL);
310 	if (!t)
311 		return -ENOMEM;
312 
313 	WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
314 
315 	spi_message_init(&m);
316 
317 	cmd = &commands[0];
318 	i = 0;
319 	while (len > 0) {
320 		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
321 
322 		*cmd = 0;
323 		*cmd |= WSPI_CMD_WRITE;
324 		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
325 			WSPI_CMD_BYTE_LENGTH;
326 		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
327 
328 		if (fixed)
329 			*cmd |= WSPI_CMD_FIXED;
330 
331 		t[i].tx_buf = cmd;
332 		t[i].len = sizeof(*cmd);
333 		spi_message_add_tail(&t[i++], &m);
334 
335 		t[i].tx_buf = buf;
336 		t[i].len = chunk_len;
337 		spi_message_add_tail(&t[i++], &m);
338 
339 		if (!fixed)
340 			addr += chunk_len;
341 		buf += chunk_len;
342 		len -= chunk_len;
343 		cmd++;
344 	}
345 
346 	spi_sync(to_spi_device(glue->dev), &m);
347 
348 	kfree(t);
349 	return 0;
350 }
351 
352 static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
353 					     void *buf, size_t len, bool fixed)
354 {
355 	/* The ELP wakeup write may fail the first time due to internal
356 	 * hardware latency. It is safer to send the wakeup command twice to
357 	 * avoid unexpected failures.
358 	 */
359 	if (addr == HW_ACCESS_ELP_CTRL_REG)
360 		__wl12xx_spi_raw_write(child, addr, buf, len, fixed);
361 
362 	return __wl12xx_spi_raw_write(child, addr, buf, len, fixed);
363 }
364 
365 /**
366  * wl12xx_spi_set_power - power on/off the wl12xx unit
367  * @child: wl12xx device handle.
368  * @enable: true/false to power on/off the unit.
369  *
370  * use the WiFi enable regulator to enable/disable the WiFi unit.
371  */
372 static int wl12xx_spi_set_power(struct device *child, bool enable)
373 {
374 	int ret = 0;
375 	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
376 
377 	WARN_ON(!glue->reg);
378 
379 	/* Update regulator state */
380 	if (enable) {
381 		ret = regulator_enable(glue->reg);
382 		if (ret)
383 			dev_err(child, "Power enable failure\n");
384 	} else {
385 		ret =  regulator_disable(glue->reg);
386 		if (ret)
387 			dev_err(child, "Power disable failure\n");
388 	}
389 
390 	return ret;
391 }
392 
393 /*
394  * wl12xx_spi_set_block_size
395  *
396  * This function is not needed for spi mode, but need to be present.
397  * Without it defined the wlcore fallback to use the wrong packet
398  * allignment on tx.
399  */
400 static void wl12xx_spi_set_block_size(struct device *child,
401 				      unsigned int blksz)
402 {
403 }
404 
405 static struct wl1271_if_operations spi_ops = {
406 	.read		= wl12xx_spi_raw_read,
407 	.write		= wl12xx_spi_raw_write,
408 	.reset		= wl12xx_spi_reset,
409 	.init		= wl12xx_spi_init,
410 	.power		= wl12xx_spi_set_power,
411 	.set_block_size = wl12xx_spi_set_block_size,
412 };
413 
414 static const struct of_device_id wlcore_spi_of_match_table[] = {
415 	{ .compatible = "ti,wl1271", .data = &wl127x_data},
416 	{ .compatible = "ti,wl1273", .data = &wl127x_data},
417 	{ .compatible = "ti,wl1281", .data = &wl128x_data},
418 	{ .compatible = "ti,wl1283", .data = &wl128x_data},
419 	{ .compatible = "ti,wl1285", .data = &wl128x_data},
420 	{ .compatible = "ti,wl1801", .data = &wl18xx_data},
421 	{ .compatible = "ti,wl1805", .data = &wl18xx_data},
422 	{ .compatible = "ti,wl1807", .data = &wl18xx_data},
423 	{ .compatible = "ti,wl1831", .data = &wl18xx_data},
424 	{ .compatible = "ti,wl1835", .data = &wl18xx_data},
425 	{ .compatible = "ti,wl1837", .data = &wl18xx_data},
426 	{ }
427 };
428 MODULE_DEVICE_TABLE(of, wlcore_spi_of_match_table);
429 
430 /**
431  * wlcore_probe_of - DT node parsing.
432  * @spi: SPI slave device parameters.
433  * @glue: wl12xx SPI bus to slave device glue parameters.
434  * @pdev_data: wlcore device parameters
435  */
436 static int wlcore_probe_of(struct spi_device *spi, struct wl12xx_spi_glue *glue,
437 			   struct wlcore_platdev_data *pdev_data)
438 {
439 	struct device_node *dt_node = spi->dev.of_node;
440 	const struct of_device_id *of_id;
441 
442 	of_id = of_match_node(wlcore_spi_of_match_table, dt_node);
443 	if (!of_id)
444 		return -ENODEV;
445 
446 	pdev_data->family = of_id->data;
447 	dev_info(&spi->dev, "selected chip family is %s\n",
448 		 pdev_data->family->name);
449 
450 	pdev_data->ref_clock_xtal = of_property_read_bool(dt_node, "clock-xtal");
451 
452 	/* optional clock frequency params */
453 	of_property_read_u32(dt_node, "ref-clock-frequency",
454 			     &pdev_data->ref_clock_freq);
455 	of_property_read_u32(dt_node, "tcxo-clock-frequency",
456 			     &pdev_data->tcxo_clock_freq);
457 
458 	return 0;
459 }
460 
461 static int wl1271_probe(struct spi_device *spi)
462 {
463 	struct wl12xx_spi_glue *glue;
464 	struct wlcore_platdev_data *pdev_data;
465 	struct resource res[1];
466 	int ret;
467 
468 	pdev_data = devm_kzalloc(&spi->dev, sizeof(*pdev_data), GFP_KERNEL);
469 	if (!pdev_data)
470 		return -ENOMEM;
471 
472 	pdev_data->if_ops = &spi_ops;
473 
474 	glue = devm_kzalloc(&spi->dev, sizeof(*glue), GFP_KERNEL);
475 	if (!glue) {
476 		dev_err(&spi->dev, "can't allocate glue\n");
477 		return -ENOMEM;
478 	}
479 
480 	glue->dev = &spi->dev;
481 
482 	spi_set_drvdata(spi, glue);
483 
484 	/* This is the only SPI value that we need to set here, the rest
485 	 * comes from the board-peripherals file */
486 	spi->bits_per_word = 32;
487 
488 	glue->reg = devm_regulator_get(&spi->dev, "vwlan");
489 	if (IS_ERR(glue->reg))
490 		return dev_err_probe(glue->dev, PTR_ERR(glue->reg),
491 				     "can't get regulator\n");
492 
493 	ret = wlcore_probe_of(spi, glue, pdev_data);
494 	if (ret) {
495 		dev_err(glue->dev,
496 			"can't get device tree parameters (%d)\n", ret);
497 		return ret;
498 	}
499 
500 	ret = spi_setup(spi);
501 	if (ret < 0) {
502 		dev_err(glue->dev, "spi_setup failed\n");
503 		return ret;
504 	}
505 
506 	glue->core = platform_device_alloc(pdev_data->family->name,
507 					   PLATFORM_DEVID_AUTO);
508 	if (!glue->core) {
509 		dev_err(glue->dev, "can't allocate platform_device\n");
510 		return -ENOMEM;
511 	}
512 
513 	glue->core->dev.parent = &spi->dev;
514 
515 	memset(res, 0x00, sizeof(res));
516 
517 	res[0].start = spi->irq;
518 	res[0].flags = IORESOURCE_IRQ | irq_get_trigger_type(spi->irq);
519 	res[0].name = "irq";
520 
521 	ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
522 	if (ret) {
523 		dev_err(glue->dev, "can't add resources\n");
524 		goto out_dev_put;
525 	}
526 
527 	ret = platform_device_add_data(glue->core, pdev_data,
528 				       sizeof(*pdev_data));
529 	if (ret) {
530 		dev_err(glue->dev, "can't add platform data\n");
531 		goto out_dev_put;
532 	}
533 
534 	ret = platform_device_add(glue->core);
535 	if (ret) {
536 		dev_err(glue->dev, "can't register platform device\n");
537 		goto out_dev_put;
538 	}
539 
540 	return 0;
541 
542 out_dev_put:
543 	platform_device_put(glue->core);
544 	return ret;
545 }
546 
547 static void wl1271_remove(struct spi_device *spi)
548 {
549 	struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
550 
551 	platform_device_unregister(glue->core);
552 }
553 
554 static struct spi_driver wl1271_spi_driver = {
555 	.driver = {
556 		.name		= "wl1271_spi",
557 		.of_match_table = of_match_ptr(wlcore_spi_of_match_table),
558 	},
559 
560 	.probe		= wl1271_probe,
561 	.remove		= wl1271_remove,
562 };
563 
564 module_spi_driver(wl1271_spi_driver);
565 MODULE_LICENSE("GPL");
566 MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
567 MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
568 MODULE_ALIAS("spi:wl1271");
569