xref: /linux/drivers/net/wireless/microchip/wilc1000/spi.c (revision 9410645520e9b820069761f3450ef6661418e279)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2012 - 2018 Microchip Technology Inc., and its subsidiaries.
4  * All rights reserved.
5  */
6 
7 #include <linux/clk.h>
8 #include <linux/spi/spi.h>
9 #include <linux/crc7.h>
10 #include <linux/crc-itu-t.h>
11 #include <linux/gpio/consumer.h>
12 
13 #include "netdev.h"
14 #include "cfg80211.h"
15 
16 #define SPI_MODALIAS		"wilc1000_spi"
17 
18 static bool enable_crc7;	/* protect SPI commands with CRC7 */
19 module_param(enable_crc7, bool, 0644);
20 MODULE_PARM_DESC(enable_crc7,
21 		 "Enable CRC7 checksum to protect command transfers\n"
22 		 "\t\t\tagainst corruption during the SPI transfer.\n"
23 		 "\t\t\tCommand transfers are short and the CPU-cycle cost\n"
24 		 "\t\t\tof enabling this is small.");
25 
26 static bool enable_crc16;	/* protect SPI data with CRC16 */
27 module_param(enable_crc16, bool, 0644);
28 MODULE_PARM_DESC(enable_crc16,
29 		 "Enable CRC16 checksum to protect data transfers\n"
30 		 "\t\t\tagainst corruption during the SPI transfer.\n"
31 		 "\t\t\tData transfers can be large and the CPU-cycle cost\n"
32 		 "\t\t\tof enabling this may be substantial.");
33 
34 /*
35  * For CMD_SINGLE_READ and CMD_INTERNAL_READ, WILC may insert one or
36  * more zero bytes between the command response and the DATA Start tag
37  * (0xf3).  This behavior appears to be undocumented in "ATWILC1000
38  * USER GUIDE" (https://tinyurl.com/4hhshdts) but we have observed 1-4
39  * zero bytes when the SPI bus operates at 48MHz and none when it
40  * operates at 1MHz.
41  */
42 #define WILC_SPI_RSP_HDR_EXTRA_DATA	8
43 
44 struct wilc_spi {
45 	bool isinit;		/* true if wilc_spi_init was successful */
46 	bool probing_crc;	/* true if we're probing chip's CRC config */
47 	bool crc7_enabled;	/* true if crc7 is currently enabled */
48 	bool crc16_enabled;	/* true if crc16 is currently enabled */
49 	struct wilc_gpios {
50 		struct gpio_desc *enable;	/* ENABLE GPIO or NULL */
51 		struct gpio_desc *reset;	/* RESET GPIO or NULL */
52 	} gpios;
53 };
54 
55 static const struct wilc_hif_func wilc_hif_spi;
56 
57 static int wilc_spi_reset(struct wilc *wilc);
58 static int wilc_spi_configure_bus_protocol(struct wilc *wilc);
59 static int wilc_validate_chipid(struct wilc *wilc);
60 
61 /********************************************
62  *
63  *      Spi protocol Function
64  *
65  ********************************************/
66 
67 #define CMD_DMA_WRITE				0xc1
68 #define CMD_DMA_READ				0xc2
69 #define CMD_INTERNAL_WRITE			0xc3
70 #define CMD_INTERNAL_READ			0xc4
71 #define CMD_TERMINATE				0xc5
72 #define CMD_REPEAT				0xc6
73 #define CMD_DMA_EXT_WRITE			0xc7
74 #define CMD_DMA_EXT_READ			0xc8
75 #define CMD_SINGLE_WRITE			0xc9
76 #define CMD_SINGLE_READ				0xca
77 #define CMD_RESET				0xcf
78 
79 #define SPI_RETRY_MAX_LIMIT			10
80 #define SPI_ENABLE_VMM_RETRY_LIMIT		2
81 
82 /* SPI response fields (section 11.1.2 in ATWILC1000 User Guide): */
83 #define RSP_START_FIELD				GENMASK(7, 4)
84 #define RSP_TYPE_FIELD				GENMASK(3, 0)
85 
86 /* SPI response values for the response fields: */
87 #define RSP_START_TAG				0xc
88 #define RSP_TYPE_FIRST_PACKET			0x1
89 #define RSP_TYPE_INNER_PACKET			0x2
90 #define RSP_TYPE_LAST_PACKET			0x3
91 #define RSP_STATE_NO_ERROR			0x00
92 
93 #define PROTOCOL_REG_PKT_SZ_MASK		GENMASK(6, 4)
94 #define PROTOCOL_REG_CRC16_MASK			GENMASK(3, 3)
95 #define PROTOCOL_REG_CRC7_MASK			GENMASK(2, 2)
96 
97 /*
98  * The SPI data packet size may be any integer power of two in the
99  * range from 256 to 8192 bytes.
100  */
101 #define DATA_PKT_LOG_SZ_MIN			8	/* 256 B */
102 #define DATA_PKT_LOG_SZ_MAX			13	/* 8 KiB */
103 
104 /*
105  * Select the data packet size (log2 of number of bytes): Use the
106  * maximum data packet size.  We only retransmit complete packets, so
107  * there is no benefit from using smaller data packets.
108  */
109 #define DATA_PKT_LOG_SZ				DATA_PKT_LOG_SZ_MAX
110 #define DATA_PKT_SZ				(1 << DATA_PKT_LOG_SZ)
111 
112 #define WILC_SPI_COMMAND_STAT_SUCCESS		0
113 #define WILC_GET_RESP_HDR_START(h)		(((h) >> 4) & 0xf)
114 
115 struct wilc_spi_cmd {
116 	u8 cmd_type;
117 	union {
118 		struct {
119 			u8 addr[3];
120 			u8 crc[];
121 		} __packed simple_cmd;
122 		struct {
123 			u8 addr[3];
124 			u8 size[2];
125 			u8 crc[];
126 		} __packed dma_cmd;
127 		struct {
128 			u8 addr[3];
129 			u8 size[3];
130 			u8 crc[];
131 		} __packed dma_cmd_ext;
132 		struct {
133 			u8 addr[2];
134 			__be32 data;
135 			u8 crc[];
136 		} __packed internal_w_cmd;
137 		struct {
138 			u8 addr[3];
139 			__be32 data;
140 			u8 crc[];
141 		} __packed w_cmd;
142 	} u;
143 } __packed;
144 
145 struct wilc_spi_read_rsp_data {
146 	u8 header;
147 	u8 data[4];
148 	u8 crc[];
149 } __packed;
150 
151 struct wilc_spi_rsp_data {
152 	u8 rsp_cmd_type;
153 	u8 status;
154 	u8 data[];
155 } __packed;
156 
157 struct wilc_spi_special_cmd_rsp {
158 	u8 skip_byte;
159 	u8 rsp_cmd_type;
160 	u8 status;
161 } __packed;
162 
wilc_parse_gpios(struct wilc * wilc)163 static int wilc_parse_gpios(struct wilc *wilc)
164 {
165 	struct spi_device *spi = to_spi_device(wilc->dev);
166 	struct wilc_spi *spi_priv = wilc->bus_data;
167 	struct wilc_gpios *gpios = &spi_priv->gpios;
168 
169 	/* get ENABLE pin and deassert it (if it is defined): */
170 	gpios->enable = devm_gpiod_get_optional(&spi->dev,
171 						"enable", GPIOD_OUT_LOW);
172 	/* get RESET pin and assert it (if it is defined): */
173 	if (gpios->enable) {
174 		/* if enable pin exists, reset must exist as well */
175 		gpios->reset = devm_gpiod_get(&spi->dev,
176 					      "reset", GPIOD_OUT_HIGH);
177 		if (IS_ERR(gpios->reset)) {
178 			dev_err(&spi->dev, "missing reset gpio.\n");
179 			return PTR_ERR(gpios->reset);
180 		}
181 	} else {
182 		gpios->reset = devm_gpiod_get_optional(&spi->dev,
183 						       "reset", GPIOD_OUT_HIGH);
184 	}
185 	return 0;
186 }
187 
wilc_wlan_power(struct wilc * wilc,bool on)188 static void wilc_wlan_power(struct wilc *wilc, bool on)
189 {
190 	struct wilc_spi *spi_priv = wilc->bus_data;
191 	struct wilc_gpios *gpios = &spi_priv->gpios;
192 
193 	if (on) {
194 		/* assert ENABLE: */
195 		gpiod_set_value(gpios->enable, 1);
196 		mdelay(5);
197 		/* deassert RESET: */
198 		gpiod_set_value(gpios->reset, 0);
199 	} else {
200 		/* assert RESET: */
201 		gpiod_set_value(gpios->reset, 1);
202 		/* deassert ENABLE: */
203 		gpiod_set_value(gpios->enable, 0);
204 	}
205 }
206 
wilc_bus_probe(struct spi_device * spi)207 static int wilc_bus_probe(struct spi_device *spi)
208 {
209 	struct wilc_spi *spi_priv;
210 	struct wilc_vif *vif;
211 	struct wilc *wilc;
212 	int ret;
213 
214 	spi_priv = kzalloc(sizeof(*spi_priv), GFP_KERNEL);
215 	if (!spi_priv)
216 		return -ENOMEM;
217 
218 	ret = wilc_cfg80211_init(&wilc, &spi->dev, WILC_HIF_SPI, &wilc_hif_spi);
219 	if (ret)
220 		goto free;
221 
222 	spi_set_drvdata(spi, wilc);
223 	wilc->dev = &spi->dev;
224 	wilc->bus_data = spi_priv;
225 	wilc->dev_irq_num = spi->irq;
226 
227 	ret = wilc_parse_gpios(wilc);
228 	if (ret < 0)
229 		goto netdev_cleanup;
230 
231 	wilc->rtc_clk = devm_clk_get_optional_enabled(&spi->dev, "rtc");
232 	if (IS_ERR(wilc->rtc_clk)) {
233 		ret = PTR_ERR(wilc->rtc_clk);
234 		goto netdev_cleanup;
235 	}
236 
237 	dev_info(&spi->dev, "Selected CRC config: crc7=%s, crc16=%s\n",
238 		 enable_crc7 ? "on" : "off", enable_crc16 ? "on" : "off");
239 
240 	/* we need power to configure the bus protocol and to read the chip id: */
241 
242 	wilc_wlan_power(wilc, true);
243 
244 	ret = wilc_spi_configure_bus_protocol(wilc);
245 	if (ret)
246 		goto power_down;
247 
248 	ret = wilc_validate_chipid(wilc);
249 	if (ret)
250 		goto power_down;
251 
252 	ret = wilc_load_mac_from_nv(wilc);
253 	if (ret) {
254 		pr_err("Can not retrieve MAC address from chip\n");
255 		goto power_down;
256 	}
257 
258 	wilc_wlan_power(wilc, false);
259 	vif = wilc_netdev_ifc_init(wilc, "wlan%d", WILC_STATION_MODE,
260 				   NL80211_IFTYPE_STATION, false);
261 	if (IS_ERR(vif)) {
262 		ret = PTR_ERR(vif);
263 		goto power_down;
264 	}
265 	return 0;
266 
267 power_down:
268 	wilc_wlan_power(wilc, false);
269 netdev_cleanup:
270 	wilc_netdev_cleanup(wilc);
271 free:
272 	kfree(spi_priv);
273 	return ret;
274 }
275 
wilc_bus_remove(struct spi_device * spi)276 static void wilc_bus_remove(struct spi_device *spi)
277 {
278 	struct wilc *wilc = spi_get_drvdata(spi);
279 	struct wilc_spi *spi_priv = wilc->bus_data;
280 
281 	wilc_netdev_cleanup(wilc);
282 	kfree(spi_priv);
283 }
284 
285 static const struct of_device_id wilc_of_match[] = {
286 	{ .compatible = "microchip,wilc1000", },
287 	{ /* sentinel */ }
288 };
289 MODULE_DEVICE_TABLE(of, wilc_of_match);
290 
291 static const struct spi_device_id wilc_spi_id[] = {
292 	{ "wilc1000", 0 },
293 	{ /* sentinel */ }
294 };
295 MODULE_DEVICE_TABLE(spi, wilc_spi_id);
296 
297 static struct spi_driver wilc_spi_driver = {
298 	.driver = {
299 		.name = SPI_MODALIAS,
300 		.of_match_table = wilc_of_match,
301 	},
302 	.id_table = wilc_spi_id,
303 	.probe =  wilc_bus_probe,
304 	.remove = wilc_bus_remove,
305 };
306 module_spi_driver(wilc_spi_driver);
307 MODULE_DESCRIPTION("Atmel WILC1000 SPI wireless driver");
308 MODULE_LICENSE("GPL");
309 
wilc_spi_tx(struct wilc * wilc,u8 * b,u32 len)310 static int wilc_spi_tx(struct wilc *wilc, u8 *b, u32 len)
311 {
312 	struct spi_device *spi = to_spi_device(wilc->dev);
313 	int ret;
314 	struct spi_message msg;
315 
316 	if (len > 0 && b) {
317 		struct spi_transfer tr = {
318 			.tx_buf = b,
319 			.len = len,
320 			.delay = {
321 				.value = 0,
322 				.unit = SPI_DELAY_UNIT_USECS
323 			},
324 		};
325 		char *r_buffer = kzalloc(len, GFP_KERNEL);
326 
327 		if (!r_buffer)
328 			return -ENOMEM;
329 
330 		tr.rx_buf = r_buffer;
331 		dev_dbg(&spi->dev, "Request writing %d bytes\n", len);
332 
333 		memset(&msg, 0, sizeof(msg));
334 		spi_message_init(&msg);
335 		spi_message_add_tail(&tr, &msg);
336 
337 		ret = spi_sync(spi, &msg);
338 		if (ret < 0)
339 			dev_err(&spi->dev, "SPI transaction failed\n");
340 
341 		kfree(r_buffer);
342 	} else {
343 		dev_err(&spi->dev,
344 			"can't write data with the following length: %d\n",
345 			len);
346 		ret = -EINVAL;
347 	}
348 
349 	return ret;
350 }
351 
wilc_spi_rx(struct wilc * wilc,u8 * rb,u32 rlen)352 static int wilc_spi_rx(struct wilc *wilc, u8 *rb, u32 rlen)
353 {
354 	struct spi_device *spi = to_spi_device(wilc->dev);
355 	int ret;
356 
357 	if (rlen > 0) {
358 		struct spi_message msg;
359 		struct spi_transfer tr = {
360 			.rx_buf = rb,
361 			.len = rlen,
362 			.delay = {
363 				.value = 0,
364 				.unit = SPI_DELAY_UNIT_USECS
365 			},
366 
367 		};
368 		char *t_buffer = kzalloc(rlen, GFP_KERNEL);
369 
370 		if (!t_buffer)
371 			return -ENOMEM;
372 
373 		tr.tx_buf = t_buffer;
374 
375 		memset(&msg, 0, sizeof(msg));
376 		spi_message_init(&msg);
377 		spi_message_add_tail(&tr, &msg);
378 
379 		ret = spi_sync(spi, &msg);
380 		if (ret < 0)
381 			dev_err(&spi->dev, "SPI transaction failed\n");
382 		kfree(t_buffer);
383 	} else {
384 		dev_err(&spi->dev,
385 			"can't read data with the following length: %u\n",
386 			rlen);
387 		ret = -EINVAL;
388 	}
389 
390 	return ret;
391 }
392 
wilc_spi_tx_rx(struct wilc * wilc,u8 * wb,u8 * rb,u32 rlen)393 static int wilc_spi_tx_rx(struct wilc *wilc, u8 *wb, u8 *rb, u32 rlen)
394 {
395 	struct spi_device *spi = to_spi_device(wilc->dev);
396 	int ret;
397 
398 	if (rlen > 0) {
399 		struct spi_message msg;
400 		struct spi_transfer tr = {
401 			.rx_buf = rb,
402 			.tx_buf = wb,
403 			.len = rlen,
404 			.bits_per_word = 8,
405 			.delay = {
406 				.value = 0,
407 				.unit = SPI_DELAY_UNIT_USECS
408 			},
409 
410 		};
411 
412 		memset(&msg, 0, sizeof(msg));
413 		spi_message_init(&msg);
414 		spi_message_add_tail(&tr, &msg);
415 		ret = spi_sync(spi, &msg);
416 		if (ret < 0)
417 			dev_err(&spi->dev, "SPI transaction failed\n");
418 	} else {
419 		dev_err(&spi->dev,
420 			"can't read data with the following length: %u\n",
421 			rlen);
422 		ret = -EINVAL;
423 	}
424 
425 	return ret;
426 }
427 
spi_data_write(struct wilc * wilc,u8 * b,u32 sz)428 static int spi_data_write(struct wilc *wilc, u8 *b, u32 sz)
429 {
430 	struct spi_device *spi = to_spi_device(wilc->dev);
431 	struct wilc_spi *spi_priv = wilc->bus_data;
432 	int ix, nbytes;
433 	int result = 0;
434 	u8 cmd, order, crc[2];
435 	u16 crc_calc;
436 
437 	/*
438 	 * Data
439 	 */
440 	ix = 0;
441 	do {
442 		if (sz <= DATA_PKT_SZ) {
443 			nbytes = sz;
444 			order = 0x3;
445 		} else {
446 			nbytes = DATA_PKT_SZ;
447 			if (ix == 0)
448 				order = 0x1;
449 			else
450 				order = 0x02;
451 		}
452 
453 		/*
454 		 * Write command
455 		 */
456 		cmd = 0xf0;
457 		cmd |= order;
458 
459 		if (wilc_spi_tx(wilc, &cmd, 1)) {
460 			dev_err(&spi->dev,
461 				"Failed data block cmd write, bus error...\n");
462 			result = -EINVAL;
463 			break;
464 		}
465 
466 		/*
467 		 * Write data
468 		 */
469 		if (wilc_spi_tx(wilc, &b[ix], nbytes)) {
470 			dev_err(&spi->dev,
471 				"Failed data block write, bus error...\n");
472 			result = -EINVAL;
473 			break;
474 		}
475 
476 		/*
477 		 * Write CRC
478 		 */
479 		if (spi_priv->crc16_enabled) {
480 			crc_calc = crc_itu_t(0xffff, &b[ix], nbytes);
481 			crc[0] = crc_calc >> 8;
482 			crc[1] = crc_calc;
483 			if (wilc_spi_tx(wilc, crc, 2)) {
484 				dev_err(&spi->dev, "Failed data block crc write, bus error...\n");
485 				result = -EINVAL;
486 				break;
487 			}
488 		}
489 
490 		/*
491 		 * No need to wait for response
492 		 */
493 		ix += nbytes;
494 		sz -= nbytes;
495 	} while (sz);
496 
497 	return result;
498 }
499 
500 /********************************************
501  *
502  *      Spi Internal Read/Write Function
503  *
504  ********************************************/
wilc_get_crc7(u8 * buffer,u32 len)505 static u8 wilc_get_crc7(u8 *buffer, u32 len)
506 {
507 	return crc7_be(0xfe, buffer, len) | 0x01;
508 }
509 
wilc_spi_single_read(struct wilc * wilc,u8 cmd,u32 adr,void * b,u8 clockless)510 static int wilc_spi_single_read(struct wilc *wilc, u8 cmd, u32 adr, void *b,
511 				u8 clockless)
512 {
513 	struct spi_device *spi = to_spi_device(wilc->dev);
514 	struct wilc_spi *spi_priv = wilc->bus_data;
515 	u8 wb[32], rb[32];
516 	int cmd_len, resp_len, i;
517 	u16 crc_calc, crc_recv;
518 	struct wilc_spi_cmd *c;
519 	struct wilc_spi_rsp_data *r;
520 	struct wilc_spi_read_rsp_data *r_data;
521 
522 	memset(wb, 0x0, sizeof(wb));
523 	memset(rb, 0x0, sizeof(rb));
524 	c = (struct wilc_spi_cmd *)wb;
525 	c->cmd_type = cmd;
526 	if (cmd == CMD_SINGLE_READ) {
527 		c->u.simple_cmd.addr[0] = adr >> 16;
528 		c->u.simple_cmd.addr[1] = adr >> 8;
529 		c->u.simple_cmd.addr[2] = adr;
530 	} else if (cmd == CMD_INTERNAL_READ) {
531 		c->u.simple_cmd.addr[0] = adr >> 8;
532 		if (clockless == 1)
533 			c->u.simple_cmd.addr[0] |= BIT(7);
534 		c->u.simple_cmd.addr[1] = adr;
535 		c->u.simple_cmd.addr[2] = 0x0;
536 	} else {
537 		dev_err(&spi->dev, "cmd [%x] not supported\n", cmd);
538 		return -EINVAL;
539 	}
540 
541 	cmd_len = offsetof(struct wilc_spi_cmd, u.simple_cmd.crc);
542 	resp_len = sizeof(*r) + sizeof(*r_data) + WILC_SPI_RSP_HDR_EXTRA_DATA;
543 
544 	if (spi_priv->crc7_enabled) {
545 		c->u.simple_cmd.crc[0] = wilc_get_crc7(wb, cmd_len);
546 		cmd_len += 1;
547 		resp_len += 2;
548 	}
549 
550 	if (cmd_len + resp_len > ARRAY_SIZE(wb)) {
551 		dev_err(&spi->dev,
552 			"spi buffer size too small (%d) (%d) (%zu)\n",
553 			cmd_len, resp_len, ARRAY_SIZE(wb));
554 		return -EINVAL;
555 	}
556 
557 	if (wilc_spi_tx_rx(wilc, wb, rb, cmd_len + resp_len)) {
558 		dev_err(&spi->dev, "Failed cmd write, bus error...\n");
559 		return -EINVAL;
560 	}
561 
562 	r = (struct wilc_spi_rsp_data *)&rb[cmd_len];
563 	if (r->rsp_cmd_type != cmd && !clockless) {
564 		if (!spi_priv->probing_crc)
565 			dev_err(&spi->dev,
566 				"Failed cmd, cmd (%02x), resp (%02x)\n",
567 				cmd, r->rsp_cmd_type);
568 		return -EINVAL;
569 	}
570 
571 	if (r->status != WILC_SPI_COMMAND_STAT_SUCCESS && !clockless) {
572 		dev_err(&spi->dev, "Failed cmd state response state (%02x)\n",
573 			r->status);
574 		return -EINVAL;
575 	}
576 
577 	for (i = 0; i < WILC_SPI_RSP_HDR_EXTRA_DATA; ++i)
578 		if (WILC_GET_RESP_HDR_START(r->data[i]) == 0xf)
579 			break;
580 
581 	if (i >= WILC_SPI_RSP_HDR_EXTRA_DATA) {
582 		dev_err(&spi->dev, "Error, data start missing\n");
583 		return -EINVAL;
584 	}
585 
586 	r_data = (struct wilc_spi_read_rsp_data *)&r->data[i];
587 
588 	if (b)
589 		memcpy(b, r_data->data, 4);
590 
591 	if (!clockless && spi_priv->crc16_enabled) {
592 		crc_recv = (r_data->crc[0] << 8) | r_data->crc[1];
593 		crc_calc = crc_itu_t(0xffff, r_data->data, 4);
594 		if (crc_recv != crc_calc) {
595 			dev_err(&spi->dev, "%s: bad CRC 0x%04x "
596 				"(calculated 0x%04x)\n", __func__,
597 				crc_recv, crc_calc);
598 			return -EINVAL;
599 		}
600 	}
601 
602 	return 0;
603 }
604 
wilc_spi_write_cmd(struct wilc * wilc,u8 cmd,u32 adr,u32 data,u8 clockless)605 static int wilc_spi_write_cmd(struct wilc *wilc, u8 cmd, u32 adr, u32 data,
606 			      u8 clockless)
607 {
608 	struct spi_device *spi = to_spi_device(wilc->dev);
609 	struct wilc_spi *spi_priv = wilc->bus_data;
610 	u8 wb[32], rb[32];
611 	int cmd_len, resp_len;
612 	struct wilc_spi_cmd *c;
613 	struct wilc_spi_rsp_data *r;
614 
615 	memset(wb, 0x0, sizeof(wb));
616 	memset(rb, 0x0, sizeof(rb));
617 	c = (struct wilc_spi_cmd *)wb;
618 	c->cmd_type = cmd;
619 	if (cmd == CMD_INTERNAL_WRITE) {
620 		c->u.internal_w_cmd.addr[0] = adr >> 8;
621 		if (clockless == 1)
622 			c->u.internal_w_cmd.addr[0] |= BIT(7);
623 
624 		c->u.internal_w_cmd.addr[1] = adr;
625 		c->u.internal_w_cmd.data = cpu_to_be32(data);
626 		cmd_len = offsetof(struct wilc_spi_cmd, u.internal_w_cmd.crc);
627 		if (spi_priv->crc7_enabled)
628 			c->u.internal_w_cmd.crc[0] = wilc_get_crc7(wb, cmd_len);
629 	} else if (cmd == CMD_SINGLE_WRITE) {
630 		c->u.w_cmd.addr[0] = adr >> 16;
631 		c->u.w_cmd.addr[1] = adr >> 8;
632 		c->u.w_cmd.addr[2] = adr;
633 		c->u.w_cmd.data = cpu_to_be32(data);
634 		cmd_len = offsetof(struct wilc_spi_cmd, u.w_cmd.crc);
635 		if (spi_priv->crc7_enabled)
636 			c->u.w_cmd.crc[0] = wilc_get_crc7(wb, cmd_len);
637 	} else {
638 		dev_err(&spi->dev, "write cmd [%x] not supported\n", cmd);
639 		return -EINVAL;
640 	}
641 
642 	if (spi_priv->crc7_enabled)
643 		cmd_len += 1;
644 
645 	resp_len = sizeof(*r);
646 
647 	if (cmd_len + resp_len > ARRAY_SIZE(wb)) {
648 		dev_err(&spi->dev,
649 			"spi buffer size too small (%d) (%d) (%zu)\n",
650 			cmd_len, resp_len, ARRAY_SIZE(wb));
651 		return -EINVAL;
652 	}
653 
654 	if (wilc_spi_tx_rx(wilc, wb, rb, cmd_len + resp_len)) {
655 		dev_err(&spi->dev, "Failed cmd write, bus error...\n");
656 		return -EINVAL;
657 	}
658 
659 	r = (struct wilc_spi_rsp_data *)&rb[cmd_len];
660 	/*
661 	 * Clockless registers operations might return unexptected responses,
662 	 * even if successful.
663 	 */
664 	if (r->rsp_cmd_type != cmd && !clockless) {
665 		dev_err(&spi->dev,
666 			"Failed cmd response, cmd (%02x), resp (%02x)\n",
667 			cmd, r->rsp_cmd_type);
668 		return -EINVAL;
669 	}
670 
671 	if (r->status != WILC_SPI_COMMAND_STAT_SUCCESS && !clockless) {
672 		dev_err(&spi->dev, "Failed cmd state response state (%02x)\n",
673 			r->status);
674 		return -EINVAL;
675 	}
676 
677 	return 0;
678 }
679 
wilc_spi_dma_rw(struct wilc * wilc,u8 cmd,u32 adr,u8 * b,u32 sz)680 static int wilc_spi_dma_rw(struct wilc *wilc, u8 cmd, u32 adr, u8 *b, u32 sz)
681 {
682 	struct spi_device *spi = to_spi_device(wilc->dev);
683 	struct wilc_spi *spi_priv = wilc->bus_data;
684 	u16 crc_recv, crc_calc;
685 	u8 wb[32], rb[32];
686 	int cmd_len, resp_len;
687 	int retry, ix = 0;
688 	u8 crc[2];
689 	struct wilc_spi_cmd *c;
690 	struct wilc_spi_rsp_data *r;
691 
692 	memset(wb, 0x0, sizeof(wb));
693 	memset(rb, 0x0, sizeof(rb));
694 	c = (struct wilc_spi_cmd *)wb;
695 	c->cmd_type = cmd;
696 	if (cmd == CMD_DMA_WRITE || cmd == CMD_DMA_READ) {
697 		c->u.dma_cmd.addr[0] = adr >> 16;
698 		c->u.dma_cmd.addr[1] = adr >> 8;
699 		c->u.dma_cmd.addr[2] = adr;
700 		c->u.dma_cmd.size[0] = sz >> 8;
701 		c->u.dma_cmd.size[1] = sz;
702 		cmd_len = offsetof(struct wilc_spi_cmd, u.dma_cmd.crc);
703 		if (spi_priv->crc7_enabled)
704 			c->u.dma_cmd.crc[0] = wilc_get_crc7(wb, cmd_len);
705 	} else if (cmd == CMD_DMA_EXT_WRITE || cmd == CMD_DMA_EXT_READ) {
706 		c->u.dma_cmd_ext.addr[0] = adr >> 16;
707 		c->u.dma_cmd_ext.addr[1] = adr >> 8;
708 		c->u.dma_cmd_ext.addr[2] = adr;
709 		c->u.dma_cmd_ext.size[0] = sz >> 16;
710 		c->u.dma_cmd_ext.size[1] = sz >> 8;
711 		c->u.dma_cmd_ext.size[2] = sz;
712 		cmd_len = offsetof(struct wilc_spi_cmd, u.dma_cmd_ext.crc);
713 		if (spi_priv->crc7_enabled)
714 			c->u.dma_cmd_ext.crc[0] = wilc_get_crc7(wb, cmd_len);
715 	} else {
716 		dev_err(&spi->dev, "dma read write cmd [%x] not supported\n",
717 			cmd);
718 		return -EINVAL;
719 	}
720 	if (spi_priv->crc7_enabled)
721 		cmd_len += 1;
722 
723 	resp_len = sizeof(*r);
724 
725 	if (cmd_len + resp_len > ARRAY_SIZE(wb)) {
726 		dev_err(&spi->dev, "spi buffer size too small (%d)(%d) (%zu)\n",
727 			cmd_len, resp_len, ARRAY_SIZE(wb));
728 		return -EINVAL;
729 	}
730 
731 	if (wilc_spi_tx_rx(wilc, wb, rb, cmd_len + resp_len)) {
732 		dev_err(&spi->dev, "Failed cmd write, bus error...\n");
733 		return -EINVAL;
734 	}
735 
736 	r = (struct wilc_spi_rsp_data *)&rb[cmd_len];
737 	if (r->rsp_cmd_type != cmd) {
738 		dev_err(&spi->dev,
739 			"Failed cmd response, cmd (%02x), resp (%02x)\n",
740 			cmd, r->rsp_cmd_type);
741 		return -EINVAL;
742 	}
743 
744 	if (r->status != WILC_SPI_COMMAND_STAT_SUCCESS) {
745 		dev_err(&spi->dev, "Failed cmd state response state (%02x)\n",
746 			r->status);
747 		return -EINVAL;
748 	}
749 
750 	if (cmd == CMD_DMA_WRITE || cmd == CMD_DMA_EXT_WRITE)
751 		return 0;
752 
753 	while (sz > 0) {
754 		int nbytes;
755 		u8 rsp;
756 
757 		nbytes = min_t(u32, sz, DATA_PKT_SZ);
758 
759 		/*
760 		 * Data Response header
761 		 */
762 		retry = 100;
763 		do {
764 			if (wilc_spi_rx(wilc, &rsp, 1)) {
765 				dev_err(&spi->dev,
766 					"Failed resp read, bus err\n");
767 				return -EINVAL;
768 			}
769 			if (WILC_GET_RESP_HDR_START(rsp) == 0xf)
770 				break;
771 		} while (retry--);
772 
773 		/*
774 		 * Read bytes
775 		 */
776 		if (wilc_spi_rx(wilc, &b[ix], nbytes)) {
777 			dev_err(&spi->dev,
778 				"Failed block read, bus err\n");
779 			return -EINVAL;
780 		}
781 
782 		/*
783 		 * Read CRC
784 		 */
785 		if (spi_priv->crc16_enabled) {
786 			if (wilc_spi_rx(wilc, crc, 2)) {
787 				dev_err(&spi->dev,
788 					"Failed block CRC read, bus err\n");
789 				return -EINVAL;
790 			}
791 			crc_recv = (crc[0] << 8) | crc[1];
792 			crc_calc = crc_itu_t(0xffff, &b[ix], nbytes);
793 			if (crc_recv != crc_calc) {
794 				dev_err(&spi->dev, "%s: bad CRC 0x%04x "
795 					"(calculated 0x%04x)\n", __func__,
796 					crc_recv, crc_calc);
797 				return -EINVAL;
798 			}
799 		}
800 
801 		ix += nbytes;
802 		sz -= nbytes;
803 	}
804 	return 0;
805 }
806 
wilc_spi_special_cmd(struct wilc * wilc,u8 cmd)807 static int wilc_spi_special_cmd(struct wilc *wilc, u8 cmd)
808 {
809 	struct spi_device *spi = to_spi_device(wilc->dev);
810 	struct wilc_spi *spi_priv = wilc->bus_data;
811 	u8 wb[32], rb[32];
812 	int cmd_len, resp_len = 0;
813 	struct wilc_spi_cmd *c;
814 	struct wilc_spi_special_cmd_rsp *r;
815 
816 	if (cmd != CMD_TERMINATE && cmd != CMD_REPEAT && cmd != CMD_RESET)
817 		return -EINVAL;
818 
819 	memset(wb, 0x0, sizeof(wb));
820 	memset(rb, 0x0, sizeof(rb));
821 	c = (struct wilc_spi_cmd *)wb;
822 	c->cmd_type = cmd;
823 
824 	if (cmd == CMD_RESET)
825 		memset(c->u.simple_cmd.addr, 0xFF, 3);
826 
827 	cmd_len = offsetof(struct wilc_spi_cmd, u.simple_cmd.crc);
828 	resp_len = sizeof(*r);
829 
830 	if (spi_priv->crc7_enabled) {
831 		c->u.simple_cmd.crc[0] = wilc_get_crc7(wb, cmd_len);
832 		cmd_len += 1;
833 	}
834 	if (cmd_len + resp_len > ARRAY_SIZE(wb)) {
835 		dev_err(&spi->dev, "spi buffer size too small (%d) (%d) (%zu)\n",
836 			cmd_len, resp_len, ARRAY_SIZE(wb));
837 		return -EINVAL;
838 	}
839 
840 	if (wilc_spi_tx_rx(wilc, wb, rb, cmd_len + resp_len)) {
841 		dev_err(&spi->dev, "Failed cmd write, bus error...\n");
842 		return -EINVAL;
843 	}
844 
845 	r = (struct wilc_spi_special_cmd_rsp *)&rb[cmd_len];
846 	if (r->rsp_cmd_type != cmd) {
847 		if (!spi_priv->probing_crc)
848 			dev_err(&spi->dev,
849 				"Failed cmd response, cmd (%02x), resp (%02x)\n",
850 				cmd, r->rsp_cmd_type);
851 		return -EINVAL;
852 	}
853 
854 	if (r->status != WILC_SPI_COMMAND_STAT_SUCCESS) {
855 		dev_err(&spi->dev, "Failed cmd state response state (%02x)\n",
856 			r->status);
857 		return -EINVAL;
858 	}
859 	return 0;
860 }
861 
wilc_spi_reset_cmd_sequence(struct wilc * wl,u8 attempt,u32 addr)862 static void wilc_spi_reset_cmd_sequence(struct wilc *wl, u8 attempt, u32 addr)
863 {
864 	struct spi_device *spi = to_spi_device(wl->dev);
865 	struct wilc_spi *spi_priv = wl->bus_data;
866 
867 	if (!spi_priv->probing_crc)
868 		dev_err(&spi->dev, "Reset and retry %d %x\n", attempt, addr);
869 
870 	usleep_range(1000, 1100);
871 	wilc_spi_reset(wl);
872 	usleep_range(1000, 1100);
873 }
874 
wilc_spi_read_reg(struct wilc * wilc,u32 addr,u32 * data)875 static int wilc_spi_read_reg(struct wilc *wilc, u32 addr, u32 *data)
876 {
877 	struct spi_device *spi = to_spi_device(wilc->dev);
878 	int result;
879 	u8 cmd = CMD_SINGLE_READ;
880 	u8 clockless = 0;
881 	u8 i;
882 
883 	if (addr <= WILC_SPI_CLOCKLESS_ADDR_LIMIT) {
884 		/* Clockless register */
885 		cmd = CMD_INTERNAL_READ;
886 		clockless = 1;
887 	}
888 
889 	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {
890 		result = wilc_spi_single_read(wilc, cmd, addr, data, clockless);
891 		if (!result) {
892 			le32_to_cpus(data);
893 			return 0;
894 		}
895 
896 		/* retry is not applicable for clockless registers */
897 		if (clockless)
898 			break;
899 
900 		dev_err(&spi->dev, "Failed cmd, read reg (%08x)...\n", addr);
901 		wilc_spi_reset_cmd_sequence(wilc, i, addr);
902 	}
903 
904 	return result;
905 }
906 
wilc_spi_read(struct wilc * wilc,u32 addr,u8 * buf,u32 size)907 static int wilc_spi_read(struct wilc *wilc, u32 addr, u8 *buf, u32 size)
908 {
909 	struct spi_device *spi = to_spi_device(wilc->dev);
910 	int result;
911 	u8 i;
912 
913 	if (size <= 4)
914 		return -EINVAL;
915 
916 	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {
917 		result = wilc_spi_dma_rw(wilc, CMD_DMA_EXT_READ, addr,
918 					 buf, size);
919 		if (!result)
920 			return 0;
921 
922 		dev_err(&spi->dev, "Failed cmd, read block (%08x)...\n", addr);
923 
924 		wilc_spi_reset_cmd_sequence(wilc, i, addr);
925 	}
926 
927 	return result;
928 }
929 
spi_internal_write(struct wilc * wilc,u32 adr,u32 dat)930 static int spi_internal_write(struct wilc *wilc, u32 adr, u32 dat)
931 {
932 	struct spi_device *spi = to_spi_device(wilc->dev);
933 	int result;
934 	u8 i;
935 
936 	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {
937 		result = wilc_spi_write_cmd(wilc, CMD_INTERNAL_WRITE, adr,
938 					    dat, 0);
939 		if (!result)
940 			return 0;
941 		dev_err(&spi->dev, "Failed internal write cmd...\n");
942 
943 		wilc_spi_reset_cmd_sequence(wilc, i, adr);
944 	}
945 
946 	return result;
947 }
948 
spi_internal_read(struct wilc * wilc,u32 adr,u32 * data)949 static int spi_internal_read(struct wilc *wilc, u32 adr, u32 *data)
950 {
951 	struct spi_device *spi = to_spi_device(wilc->dev);
952 	struct wilc_spi *spi_priv = wilc->bus_data;
953 	int result;
954 	u8 i;
955 
956 	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {
957 		result = wilc_spi_single_read(wilc, CMD_INTERNAL_READ, adr,
958 					      data, 0);
959 		if (!result) {
960 			le32_to_cpus(data);
961 			return 0;
962 		}
963 		if (!spi_priv->probing_crc)
964 			dev_err(&spi->dev, "Failed internal read cmd...\n");
965 
966 		wilc_spi_reset_cmd_sequence(wilc, i, adr);
967 	}
968 
969 	return result;
970 }
971 
972 /********************************************
973  *
974  *      Spi interfaces
975  *
976  ********************************************/
977 
wilc_spi_write_reg(struct wilc * wilc,u32 addr,u32 data)978 static int wilc_spi_write_reg(struct wilc *wilc, u32 addr, u32 data)
979 {
980 	struct spi_device *spi = to_spi_device(wilc->dev);
981 	int result;
982 	u8 cmd = CMD_SINGLE_WRITE;
983 	u8 clockless = 0;
984 	u8 i;
985 
986 	if (addr <= WILC_SPI_CLOCKLESS_ADDR_LIMIT) {
987 		/* Clockless register */
988 		cmd = CMD_INTERNAL_WRITE;
989 		clockless = 1;
990 	}
991 
992 	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {
993 		result = wilc_spi_write_cmd(wilc, cmd, addr, data, clockless);
994 		if (!result)
995 			return 0;
996 
997 		dev_err(&spi->dev, "Failed cmd, write reg (%08x)...\n", addr);
998 
999 		if (clockless)
1000 			break;
1001 
1002 		wilc_spi_reset_cmd_sequence(wilc, i, addr);
1003 	}
1004 	return result;
1005 }
1006 
spi_data_rsp(struct wilc * wilc,u8 cmd)1007 static int spi_data_rsp(struct wilc *wilc, u8 cmd)
1008 {
1009 	struct spi_device *spi = to_spi_device(wilc->dev);
1010 	int result, i;
1011 	u8 rsp[4];
1012 
1013 	/*
1014 	 * The response to data packets is two bytes long.  For
1015 	 * efficiency's sake, wilc_spi_write() wisely ignores the
1016 	 * responses for all packets but the final one.  The downside
1017 	 * of that optimization is that when the final data packet is
1018 	 * short, we may receive (part of) the response to the
1019 	 * second-to-last packet before the one for the final packet.
1020 	 * To handle this, we always read 4 bytes and then search for
1021 	 * the last byte that contains the "Response Start" code (0xc
1022 	 * in the top 4 bits).  We then know that this byte is the
1023 	 * first response byte of the final data packet.
1024 	 */
1025 	result = wilc_spi_rx(wilc, rsp, sizeof(rsp));
1026 	if (result) {
1027 		dev_err(&spi->dev, "Failed bus error...\n");
1028 		return result;
1029 	}
1030 
1031 	for (i = sizeof(rsp) - 2; i >= 0; --i)
1032 		if (FIELD_GET(RSP_START_FIELD, rsp[i]) == RSP_START_TAG)
1033 			break;
1034 
1035 	if (i < 0) {
1036 		dev_err(&spi->dev,
1037 			"Data packet response missing (%02x %02x %02x %02x)\n",
1038 			rsp[0], rsp[1], rsp[2], rsp[3]);
1039 		return -1;
1040 	}
1041 
1042 	/* rsp[i] is the last response start byte */
1043 
1044 	if (FIELD_GET(RSP_TYPE_FIELD, rsp[i]) != RSP_TYPE_LAST_PACKET
1045 	    || rsp[i + 1] != RSP_STATE_NO_ERROR) {
1046 		dev_err(&spi->dev, "Data response error (%02x %02x)\n",
1047 			rsp[i], rsp[i + 1]);
1048 		return -1;
1049 	}
1050 	return 0;
1051 }
1052 
wilc_spi_write(struct wilc * wilc,u32 addr,u8 * buf,u32 size)1053 static int wilc_spi_write(struct wilc *wilc, u32 addr, u8 *buf, u32 size)
1054 {
1055 	struct spi_device *spi = to_spi_device(wilc->dev);
1056 	int result;
1057 	u8 i;
1058 
1059 	/*
1060 	 * has to be greated than 4
1061 	 */
1062 	if (size <= 4)
1063 		return -EINVAL;
1064 
1065 	for (i = 0; i < SPI_RETRY_MAX_LIMIT; i++) {
1066 		result = wilc_spi_dma_rw(wilc, CMD_DMA_EXT_WRITE, addr,
1067 					 NULL, size);
1068 		if (result) {
1069 			dev_err(&spi->dev,
1070 				"Failed cmd, write block (%08x)...\n", addr);
1071 			wilc_spi_reset_cmd_sequence(wilc, i, addr);
1072 			continue;
1073 		}
1074 
1075 		/*
1076 		 * Data
1077 		 */
1078 		result = spi_data_write(wilc, buf, size);
1079 		if (result) {
1080 			dev_err(&spi->dev, "Failed block data write...\n");
1081 			wilc_spi_reset_cmd_sequence(wilc, i, addr);
1082 			continue;
1083 		}
1084 
1085 		/*
1086 		 * Data response
1087 		 */
1088 		result = spi_data_rsp(wilc, CMD_DMA_EXT_WRITE);
1089 		if (result) {
1090 			dev_err(&spi->dev, "Failed block data rsp...\n");
1091 			wilc_spi_reset_cmd_sequence(wilc, i, addr);
1092 			continue;
1093 		}
1094 		break;
1095 	}
1096 	return result;
1097 }
1098 
1099 /********************************************
1100  *
1101  *      Bus interfaces
1102  *
1103  ********************************************/
1104 
wilc_spi_reset(struct wilc * wilc)1105 static int wilc_spi_reset(struct wilc *wilc)
1106 {
1107 	struct spi_device *spi = to_spi_device(wilc->dev);
1108 	struct wilc_spi *spi_priv = wilc->bus_data;
1109 	int result;
1110 
1111 	result = wilc_spi_special_cmd(wilc, CMD_RESET);
1112 	if (result && !spi_priv->probing_crc)
1113 		dev_err(&spi->dev, "Failed cmd reset\n");
1114 
1115 	return result;
1116 }
1117 
wilc_spi_is_init(struct wilc * wilc)1118 static bool wilc_spi_is_init(struct wilc *wilc)
1119 {
1120 	struct wilc_spi *spi_priv = wilc->bus_data;
1121 
1122 	return spi_priv->isinit;
1123 }
1124 
wilc_spi_deinit(struct wilc * wilc)1125 static int wilc_spi_deinit(struct wilc *wilc)
1126 {
1127 	struct wilc_spi *spi_priv = wilc->bus_data;
1128 
1129 	spi_priv->isinit = false;
1130 	wilc_wlan_power(wilc, false);
1131 	return 0;
1132 }
1133 
wilc_spi_init(struct wilc * wilc,bool resume)1134 static int wilc_spi_init(struct wilc *wilc, bool resume)
1135 {
1136 	struct wilc_spi *spi_priv = wilc->bus_data;
1137 	int ret;
1138 
1139 	if (spi_priv->isinit) {
1140 		/* Confirm we can read chipid register without error: */
1141 		if (wilc_validate_chipid(wilc) == 0)
1142 			return 0;
1143 	}
1144 
1145 	wilc_wlan_power(wilc, true);
1146 
1147 	ret = wilc_spi_configure_bus_protocol(wilc);
1148 	if (ret) {
1149 		wilc_wlan_power(wilc, false);
1150 		return ret;
1151 	}
1152 
1153 	spi_priv->isinit = true;
1154 
1155 	return 0;
1156 }
1157 
wilc_spi_configure_bus_protocol(struct wilc * wilc)1158 static int wilc_spi_configure_bus_protocol(struct wilc *wilc)
1159 {
1160 	struct spi_device *spi = to_spi_device(wilc->dev);
1161 	struct wilc_spi *spi_priv = wilc->bus_data;
1162 	u32 reg;
1163 	int ret, i;
1164 
1165 	/*
1166 	 * Infer the CRC settings that are currently in effect.  This
1167 	 * is necessary because we can't be sure that the chip has
1168 	 * been RESET (e.g, after module unload and reload).
1169 	 */
1170 	spi_priv->probing_crc = true;
1171 	spi_priv->crc7_enabled = enable_crc7;
1172 	spi_priv->crc16_enabled = false; /* don't check CRC16 during probing */
1173 	for (i = 0; i < 2; ++i) {
1174 		ret = spi_internal_read(wilc, WILC_SPI_PROTOCOL_OFFSET, &reg);
1175 		if (ret == 0)
1176 			break;
1177 		spi_priv->crc7_enabled = !enable_crc7;
1178 	}
1179 	if (ret) {
1180 		dev_err(&spi->dev, "Failed with CRC7 on and off.\n");
1181 		return ret;
1182 	}
1183 
1184 	/* set up the desired CRC configuration: */
1185 	reg &= ~(PROTOCOL_REG_CRC7_MASK | PROTOCOL_REG_CRC16_MASK);
1186 	if (enable_crc7)
1187 		reg |= PROTOCOL_REG_CRC7_MASK;
1188 	if (enable_crc16)
1189 		reg |= PROTOCOL_REG_CRC16_MASK;
1190 
1191 	/* set up the data packet size: */
1192 	BUILD_BUG_ON(DATA_PKT_LOG_SZ < DATA_PKT_LOG_SZ_MIN
1193 		     || DATA_PKT_LOG_SZ > DATA_PKT_LOG_SZ_MAX);
1194 	reg &= ~PROTOCOL_REG_PKT_SZ_MASK;
1195 	reg |= FIELD_PREP(PROTOCOL_REG_PKT_SZ_MASK,
1196 			  DATA_PKT_LOG_SZ - DATA_PKT_LOG_SZ_MIN);
1197 
1198 	/* establish the new setup: */
1199 	ret = spi_internal_write(wilc, WILC_SPI_PROTOCOL_OFFSET, reg);
1200 	if (ret) {
1201 		dev_err(&spi->dev,
1202 			"[wilc spi %d]: Failed internal write reg\n",
1203 			__LINE__);
1204 		return ret;
1205 	}
1206 	/* update our state to match new protocol settings: */
1207 	spi_priv->crc7_enabled = enable_crc7;
1208 	spi_priv->crc16_enabled = enable_crc16;
1209 
1210 	/* re-read to make sure new settings are in effect: */
1211 	spi_internal_read(wilc, WILC_SPI_PROTOCOL_OFFSET, &reg);
1212 
1213 	spi_priv->probing_crc = false;
1214 
1215 	return 0;
1216 }
1217 
wilc_validate_chipid(struct wilc * wilc)1218 static int wilc_validate_chipid(struct wilc *wilc)
1219 {
1220 	struct spi_device *spi = to_spi_device(wilc->dev);
1221 	u32 chipid;
1222 	int ret;
1223 
1224 	/*
1225 	 * make sure can read chip id without protocol error
1226 	 */
1227 	ret = wilc_spi_read_reg(wilc, WILC_CHIPID, &chipid);
1228 	if (ret) {
1229 		dev_err(&spi->dev, "Fail cmd read chip id...\n");
1230 		return ret;
1231 	}
1232 	if (!is_wilc1000(chipid)) {
1233 		dev_err(&spi->dev, "Unknown chip id 0x%x\n", chipid);
1234 		return -ENODEV;
1235 	}
1236 	return 0;
1237 }
1238 
wilc_spi_read_size(struct wilc * wilc,u32 * size)1239 static int wilc_spi_read_size(struct wilc *wilc, u32 *size)
1240 {
1241 	int ret;
1242 
1243 	ret = spi_internal_read(wilc,
1244 				WILC_SPI_INT_STATUS - WILC_SPI_REG_BASE, size);
1245 	*size = FIELD_GET(IRQ_DMA_WD_CNT_MASK, *size);
1246 
1247 	return ret;
1248 }
1249 
wilc_spi_read_int(struct wilc * wilc,u32 * int_status)1250 static int wilc_spi_read_int(struct wilc *wilc, u32 *int_status)
1251 {
1252 	return spi_internal_read(wilc, WILC_SPI_INT_STATUS - WILC_SPI_REG_BASE,
1253 				 int_status);
1254 }
1255 
wilc_spi_clear_int_ext(struct wilc * wilc,u32 val)1256 static int wilc_spi_clear_int_ext(struct wilc *wilc, u32 val)
1257 {
1258 	int ret;
1259 	int retry = SPI_ENABLE_VMM_RETRY_LIMIT;
1260 	u32 check;
1261 
1262 	while (retry) {
1263 		ret = spi_internal_write(wilc,
1264 					 WILC_SPI_INT_CLEAR - WILC_SPI_REG_BASE,
1265 					 val);
1266 		if (ret)
1267 			break;
1268 
1269 		ret = spi_internal_read(wilc,
1270 					WILC_SPI_INT_CLEAR - WILC_SPI_REG_BASE,
1271 					&check);
1272 		if (ret || ((check & EN_VMM) == (val & EN_VMM)))
1273 			break;
1274 
1275 		retry--;
1276 	}
1277 	return ret;
1278 }
1279 
wilc_spi_sync_ext(struct wilc * wilc,int nint)1280 static int wilc_spi_sync_ext(struct wilc *wilc, int nint)
1281 {
1282 	struct spi_device *spi = to_spi_device(wilc->dev);
1283 	u32 reg;
1284 	int ret, i;
1285 
1286 	if (nint > MAX_NUM_INT) {
1287 		dev_err(&spi->dev, "Too many interrupts (%d)...\n", nint);
1288 		return -EINVAL;
1289 	}
1290 
1291 	/*
1292 	 * interrupt pin mux select
1293 	 */
1294 	ret = wilc_spi_read_reg(wilc, WILC_PIN_MUX_0, &reg);
1295 	if (ret) {
1296 		dev_err(&spi->dev, "Failed read reg (%08x)...\n",
1297 			WILC_PIN_MUX_0);
1298 		return ret;
1299 	}
1300 	reg |= BIT(8);
1301 	ret = wilc_spi_write_reg(wilc, WILC_PIN_MUX_0, reg);
1302 	if (ret) {
1303 		dev_err(&spi->dev, "Failed write reg (%08x)...\n",
1304 			WILC_PIN_MUX_0);
1305 		return ret;
1306 	}
1307 
1308 	/*
1309 	 * interrupt enable
1310 	 */
1311 	ret = wilc_spi_read_reg(wilc, WILC_INTR_ENABLE, &reg);
1312 	if (ret) {
1313 		dev_err(&spi->dev, "Failed read reg (%08x)...\n",
1314 			WILC_INTR_ENABLE);
1315 		return ret;
1316 	}
1317 
1318 	for (i = 0; (i < 5) && (nint > 0); i++, nint--)
1319 		reg |= (BIT((27 + i)));
1320 
1321 	ret = wilc_spi_write_reg(wilc, WILC_INTR_ENABLE, reg);
1322 	if (ret) {
1323 		dev_err(&spi->dev, "Failed write reg (%08x)...\n",
1324 			WILC_INTR_ENABLE);
1325 		return ret;
1326 	}
1327 	if (nint) {
1328 		ret = wilc_spi_read_reg(wilc, WILC_INTR2_ENABLE, &reg);
1329 		if (ret) {
1330 			dev_err(&spi->dev, "Failed read reg (%08x)...\n",
1331 				WILC_INTR2_ENABLE);
1332 			return ret;
1333 		}
1334 
1335 		for (i = 0; (i < 3) && (nint > 0); i++, nint--)
1336 			reg |= BIT(i);
1337 
1338 		ret = wilc_spi_write_reg(wilc, WILC_INTR2_ENABLE, reg);
1339 		if (ret) {
1340 			dev_err(&spi->dev, "Failed write reg (%08x)...\n",
1341 				WILC_INTR2_ENABLE);
1342 			return ret;
1343 		}
1344 	}
1345 
1346 	return 0;
1347 }
1348 
1349 /* Global spi HIF function table */
1350 static const struct wilc_hif_func wilc_hif_spi = {
1351 	.hif_init = wilc_spi_init,
1352 	.hif_deinit = wilc_spi_deinit,
1353 	.hif_read_reg = wilc_spi_read_reg,
1354 	.hif_write_reg = wilc_spi_write_reg,
1355 	.hif_block_rx = wilc_spi_read,
1356 	.hif_block_tx = wilc_spi_write,
1357 	.hif_read_int = wilc_spi_read_int,
1358 	.hif_clear_int_ext = wilc_spi_clear_int_ext,
1359 	.hif_read_size = wilc_spi_read_size,
1360 	.hif_block_tx_ext = wilc_spi_write,
1361 	.hif_block_rx_ext = wilc_spi_read,
1362 	.hif_sync_ext = wilc_spi_sync_ext,
1363 	.hif_reset = wilc_spi_reset,
1364 	.hif_is_init = wilc_spi_is_init,
1365 };
1366