xref: /openbmc/linux/drivers/net/wireless/ti/wl1251/spi.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * This file is part of wl1251
4  *
5  * Copyright (C) 2008 Nokia Corporation
6  */
7 
8 #include <linux/interrupt.h>
9 #include <linux/irq.h>
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/swab.h>
13 #include <linux/crc7.h>
14 #include <linux/spi/spi.h>
15 #include <linux/wl12xx.h>
16 #include <linux/gpio.h>
17 #include <linux/of.h>
18 #include <linux/of_gpio.h>
19 #include <linux/regulator/consumer.h>
20 
21 #include "wl1251.h"
22 #include "reg.h"
23 #include "spi.h"
24 
25 static irqreturn_t wl1251_irq(int irq, void *cookie)
26 {
27 	struct wl1251 *wl;
28 
29 	wl1251_debug(DEBUG_IRQ, "IRQ");
30 
31 	wl = cookie;
32 
33 	ieee80211_queue_work(wl->hw, &wl->irq_work);
34 
35 	return IRQ_HANDLED;
36 }
37 
38 static struct spi_device *wl_to_spi(struct wl1251 *wl)
39 {
40 	return wl->if_priv;
41 }
42 
43 static void wl1251_spi_reset(struct wl1251 *wl)
44 {
45 	u8 *cmd;
46 	struct spi_transfer t;
47 	struct spi_message m;
48 
49 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
50 	if (!cmd) {
51 		wl1251_error("could not allocate cmd for spi reset");
52 		return;
53 	}
54 
55 	memset(&t, 0, sizeof(t));
56 	spi_message_init(&m);
57 
58 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
59 
60 	t.tx_buf = cmd;
61 	t.len = WSPI_INIT_CMD_LEN;
62 	spi_message_add_tail(&t, &m);
63 
64 	spi_sync(wl_to_spi(wl), &m);
65 
66 	wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
67 
68 	kfree(cmd);
69 }
70 
71 static void wl1251_spi_wake(struct wl1251 *wl)
72 {
73 	struct spi_transfer t;
74 	struct spi_message m;
75 	u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
76 
77 	if (!cmd) {
78 		wl1251_error("could not allocate cmd for spi init");
79 		return;
80 	}
81 
82 	memset(&t, 0, sizeof(t));
83 	spi_message_init(&m);
84 
85 	/* Set WSPI_INIT_COMMAND
86 	 * the data is being send from the MSB to LSB
87 	 */
88 	cmd[0] = 0xff;
89 	cmd[1] = 0xff;
90 	cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
91 	cmd[3] = 0;
92 	cmd[4] = 0;
93 	cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
94 	cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
95 
96 	cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
97 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
98 
99 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
100 		cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
101 	else
102 		cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
103 
104 	cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
105 	/*
106 	 * The above is the logical order; it must actually be stored
107 	 * in the buffer byte-swapped.
108 	 */
109 	__swab32s((u32 *)cmd);
110 	__swab32s((u32 *)cmd+1);
111 
112 	t.tx_buf = cmd;
113 	t.len = WSPI_INIT_CMD_LEN;
114 	spi_message_add_tail(&t, &m);
115 
116 	spi_sync(wl_to_spi(wl), &m);
117 
118 	wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
119 
120 	kfree(cmd);
121 }
122 
123 static void wl1251_spi_reset_wake(struct wl1251 *wl)
124 {
125 	wl1251_spi_reset(wl);
126 	wl1251_spi_wake(wl);
127 }
128 
129 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
130 			    size_t len)
131 {
132 	struct spi_transfer t[3];
133 	struct spi_message m;
134 	u8 *busy_buf;
135 	u32 *cmd;
136 
137 	cmd = &wl->buffer_cmd;
138 	busy_buf = wl->buffer_busyword;
139 
140 	*cmd = 0;
141 	*cmd |= WSPI_CMD_READ;
142 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
143 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
144 
145 	spi_message_init(&m);
146 	memset(t, 0, sizeof(t));
147 
148 	t[0].tx_buf = cmd;
149 	t[0].len = 4;
150 	spi_message_add_tail(&t[0], &m);
151 
152 	/* Busy and non busy words read */
153 	t[1].rx_buf = busy_buf;
154 	t[1].len = WL1251_BUSY_WORD_LEN;
155 	spi_message_add_tail(&t[1], &m);
156 
157 	t[2].rx_buf = buf;
158 	t[2].len = len;
159 	spi_message_add_tail(&t[2], &m);
160 
161 	spi_sync(wl_to_spi(wl), &m);
162 
163 	/* FIXME: check busy words */
164 
165 	wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
166 	wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
167 }
168 
169 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
170 			     size_t len)
171 {
172 	struct spi_transfer t[2];
173 	struct spi_message m;
174 	u32 *cmd;
175 
176 	cmd = &wl->buffer_cmd;
177 
178 	*cmd = 0;
179 	*cmd |= WSPI_CMD_WRITE;
180 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
181 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
182 
183 	spi_message_init(&m);
184 	memset(t, 0, sizeof(t));
185 
186 	t[0].tx_buf = cmd;
187 	t[0].len = sizeof(*cmd);
188 	spi_message_add_tail(&t[0], &m);
189 
190 	t[1].tx_buf = buf;
191 	t[1].len = len;
192 	spi_message_add_tail(&t[1], &m);
193 
194 	spi_sync(wl_to_spi(wl), &m);
195 
196 	wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
197 	wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
198 }
199 
200 static void wl1251_spi_enable_irq(struct wl1251 *wl)
201 {
202 	return enable_irq(wl->irq);
203 }
204 
205 static void wl1251_spi_disable_irq(struct wl1251 *wl)
206 {
207 	return disable_irq(wl->irq);
208 }
209 
210 static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
211 {
212 	if (gpio_is_valid(wl->power_gpio))
213 		gpio_set_value(wl->power_gpio, enable);
214 
215 	return 0;
216 }
217 
218 static const struct wl1251_if_operations wl1251_spi_ops = {
219 	.read = wl1251_spi_read,
220 	.write = wl1251_spi_write,
221 	.reset = wl1251_spi_reset_wake,
222 	.enable_irq = wl1251_spi_enable_irq,
223 	.disable_irq = wl1251_spi_disable_irq,
224 	.power = wl1251_spi_set_power,
225 };
226 
227 static int wl1251_spi_probe(struct spi_device *spi)
228 {
229 	struct wl1251_platform_data *pdata = dev_get_platdata(&spi->dev);
230 	struct device_node *np = spi->dev.of_node;
231 	struct ieee80211_hw *hw;
232 	struct wl1251 *wl;
233 	int ret;
234 
235 	if (!np && !pdata) {
236 		wl1251_error("no platform data");
237 		return -ENODEV;
238 	}
239 
240 	hw = wl1251_alloc_hw();
241 	if (IS_ERR(hw))
242 		return PTR_ERR(hw);
243 
244 	wl = hw->priv;
245 
246 	SET_IEEE80211_DEV(hw, &spi->dev);
247 	spi_set_drvdata(spi, wl);
248 	wl->if_priv = spi;
249 	wl->if_ops = &wl1251_spi_ops;
250 
251 	/* This is the only SPI value that we need to set here, the rest
252 	 * comes from the board-peripherals file
253 	 */
254 	spi->bits_per_word = 32;
255 
256 	ret = spi_setup(spi);
257 	if (ret < 0) {
258 		wl1251_error("spi_setup failed");
259 		goto out_free;
260 	}
261 
262 	if (np) {
263 		wl->use_eeprom = of_property_read_bool(np, "ti,wl1251-has-eeprom");
264 		wl->power_gpio = of_get_named_gpio(np, "ti,power-gpio", 0);
265 	} else if (pdata) {
266 		wl->power_gpio = pdata->power_gpio;
267 		wl->use_eeprom = pdata->use_eeprom;
268 	}
269 
270 	if (wl->power_gpio == -EPROBE_DEFER) {
271 		ret = -EPROBE_DEFER;
272 		goto out_free;
273 	}
274 
275 	if (gpio_is_valid(wl->power_gpio)) {
276 		ret = devm_gpio_request_one(&spi->dev, wl->power_gpio,
277 					GPIOF_OUT_INIT_LOW, "wl1251 power");
278 		if (ret) {
279 			wl1251_error("Failed to request gpio: %d\n", ret);
280 			goto out_free;
281 		}
282 	} else {
283 		wl1251_error("set power gpio missing in platform data");
284 		ret = -ENODEV;
285 		goto out_free;
286 	}
287 
288 	wl->irq = spi->irq;
289 	if (wl->irq < 0) {
290 		wl1251_error("irq missing in platform data");
291 		ret = -ENODEV;
292 		goto out_free;
293 	}
294 
295 	irq_set_status_flags(wl->irq, IRQ_NOAUTOEN);
296 	ret = devm_request_irq(&spi->dev, wl->irq, wl1251_irq, 0,
297 							DRIVER_NAME, wl);
298 	if (ret < 0) {
299 		wl1251_error("request_irq() failed: %d", ret);
300 		goto out_free;
301 	}
302 
303 	irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
304 
305 	wl->vio = devm_regulator_get(&spi->dev, "vio");
306 	if (IS_ERR(wl->vio)) {
307 		ret = PTR_ERR(wl->vio);
308 		wl1251_error("vio regulator missing: %d", ret);
309 		goto out_free;
310 	}
311 
312 	ret = regulator_enable(wl->vio);
313 	if (ret)
314 		goto out_free;
315 
316 	ret = wl1251_init_ieee80211(wl);
317 	if (ret)
318 		goto disable_regulator;
319 
320 	return 0;
321 
322 disable_regulator:
323 	regulator_disable(wl->vio);
324 out_free:
325 	ieee80211_free_hw(hw);
326 
327 	return ret;
328 }
329 
330 static void wl1251_spi_remove(struct spi_device *spi)
331 {
332 	struct wl1251 *wl = spi_get_drvdata(spi);
333 
334 	wl1251_free_hw(wl);
335 	regulator_disable(wl->vio);
336 }
337 
338 static struct spi_driver wl1251_spi_driver = {
339 	.driver = {
340 		.name		= DRIVER_NAME,
341 	},
342 
343 	.probe		= wl1251_spi_probe,
344 	.remove		= wl1251_spi_remove,
345 };
346 
347 module_spi_driver(wl1251_spi_driver);
348 
349 MODULE_LICENSE("GPL");
350 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
351 MODULE_ALIAS("spi:wl1251");
352