xref: /openbmc/linux/drivers/net/wireless/ti/wl1251/spi.c (revision afb46f79)
1 /*
2  * This file is part of wl1251
3  *
4  * Copyright (C) 2008 Nokia Corporation
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * version 2 as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
18  * 02110-1301 USA
19  *
20  */
21 
22 #include <linux/interrupt.h>
23 #include <linux/irq.h>
24 #include <linux/module.h>
25 #include <linux/slab.h>
26 #include <linux/crc7.h>
27 #include <linux/spi/spi.h>
28 #include <linux/wl12xx.h>
29 #include <linux/gpio.h>
30 #include <linux/of.h>
31 #include <linux/of_gpio.h>
32 #include <linux/regulator/consumer.h>
33 
34 #include "wl1251.h"
35 #include "reg.h"
36 #include "spi.h"
37 
38 static irqreturn_t wl1251_irq(int irq, void *cookie)
39 {
40 	struct wl1251 *wl;
41 
42 	wl1251_debug(DEBUG_IRQ, "IRQ");
43 
44 	wl = cookie;
45 
46 	ieee80211_queue_work(wl->hw, &wl->irq_work);
47 
48 	return IRQ_HANDLED;
49 }
50 
51 static struct spi_device *wl_to_spi(struct wl1251 *wl)
52 {
53 	return wl->if_priv;
54 }
55 
56 static void wl1251_spi_reset(struct wl1251 *wl)
57 {
58 	u8 *cmd;
59 	struct spi_transfer t;
60 	struct spi_message m;
61 
62 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
63 	if (!cmd) {
64 		wl1251_error("could not allocate cmd for spi reset");
65 		return;
66 	}
67 
68 	memset(&t, 0, sizeof(t));
69 	spi_message_init(&m);
70 
71 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
72 
73 	t.tx_buf = cmd;
74 	t.len = WSPI_INIT_CMD_LEN;
75 	spi_message_add_tail(&t, &m);
76 
77 	spi_sync(wl_to_spi(wl), &m);
78 
79 	wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
80 
81 	kfree(cmd);
82 }
83 
84 static void wl1251_spi_wake(struct wl1251 *wl)
85 {
86 	u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
87 	struct spi_transfer t;
88 	struct spi_message m;
89 
90 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
91 	if (!cmd) {
92 		wl1251_error("could not allocate cmd for spi init");
93 		return;
94 	}
95 
96 	memset(crc, 0, sizeof(crc));
97 	memset(&t, 0, sizeof(t));
98 	spi_message_init(&m);
99 
100 	/* Set WSPI_INIT_COMMAND
101 	 * the data is being send from the MSB to LSB
102 	 */
103 	cmd[2] = 0xff;
104 	cmd[3] = 0xff;
105 	cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
106 	cmd[0] = 0;
107 	cmd[7] = 0;
108 	cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
109 	cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
110 
111 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
112 		cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
113 	else
114 		cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
115 
116 	cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
117 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
118 
119 	crc[0] = cmd[1];
120 	crc[1] = cmd[0];
121 	crc[2] = cmd[7];
122 	crc[3] = cmd[6];
123 	crc[4] = cmd[5];
124 
125 	cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
126 	cmd[4] |= WSPI_INIT_CMD_END;
127 
128 	t.tx_buf = cmd;
129 	t.len = WSPI_INIT_CMD_LEN;
130 	spi_message_add_tail(&t, &m);
131 
132 	spi_sync(wl_to_spi(wl), &m);
133 
134 	wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
135 
136 	kfree(cmd);
137 }
138 
139 static void wl1251_spi_reset_wake(struct wl1251 *wl)
140 {
141 	wl1251_spi_reset(wl);
142 	wl1251_spi_wake(wl);
143 }
144 
145 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
146 			    size_t len)
147 {
148 	struct spi_transfer t[3];
149 	struct spi_message m;
150 	u8 *busy_buf;
151 	u32 *cmd;
152 
153 	cmd = &wl->buffer_cmd;
154 	busy_buf = wl->buffer_busyword;
155 
156 	*cmd = 0;
157 	*cmd |= WSPI_CMD_READ;
158 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
159 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
160 
161 	spi_message_init(&m);
162 	memset(t, 0, sizeof(t));
163 
164 	t[0].tx_buf = cmd;
165 	t[0].len = 4;
166 	spi_message_add_tail(&t[0], &m);
167 
168 	/* Busy and non busy words read */
169 	t[1].rx_buf = busy_buf;
170 	t[1].len = WL1251_BUSY_WORD_LEN;
171 	spi_message_add_tail(&t[1], &m);
172 
173 	t[2].rx_buf = buf;
174 	t[2].len = len;
175 	spi_message_add_tail(&t[2], &m);
176 
177 	spi_sync(wl_to_spi(wl), &m);
178 
179 	/* FIXME: check busy words */
180 
181 	wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
182 	wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
183 }
184 
185 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
186 			     size_t len)
187 {
188 	struct spi_transfer t[2];
189 	struct spi_message m;
190 	u32 *cmd;
191 
192 	cmd = &wl->buffer_cmd;
193 
194 	*cmd = 0;
195 	*cmd |= WSPI_CMD_WRITE;
196 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
197 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
198 
199 	spi_message_init(&m);
200 	memset(t, 0, sizeof(t));
201 
202 	t[0].tx_buf = cmd;
203 	t[0].len = sizeof(*cmd);
204 	spi_message_add_tail(&t[0], &m);
205 
206 	t[1].tx_buf = buf;
207 	t[1].len = len;
208 	spi_message_add_tail(&t[1], &m);
209 
210 	spi_sync(wl_to_spi(wl), &m);
211 
212 	wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
213 	wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
214 }
215 
216 static void wl1251_spi_enable_irq(struct wl1251 *wl)
217 {
218 	return enable_irq(wl->irq);
219 }
220 
221 static void wl1251_spi_disable_irq(struct wl1251 *wl)
222 {
223 	return disable_irq(wl->irq);
224 }
225 
226 static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
227 {
228 	if (gpio_is_valid(wl->power_gpio))
229 		gpio_set_value(wl->power_gpio, enable);
230 
231 	return 0;
232 }
233 
234 static const struct wl1251_if_operations wl1251_spi_ops = {
235 	.read = wl1251_spi_read,
236 	.write = wl1251_spi_write,
237 	.reset = wl1251_spi_reset_wake,
238 	.enable_irq = wl1251_spi_enable_irq,
239 	.disable_irq = wl1251_spi_disable_irq,
240 	.power = wl1251_spi_set_power,
241 };
242 
243 static int wl1251_spi_probe(struct spi_device *spi)
244 {
245 	struct wl1251_platform_data *pdata = dev_get_platdata(&spi->dev);
246 	struct device_node *np = spi->dev.of_node;
247 	struct ieee80211_hw *hw;
248 	struct wl1251 *wl;
249 	int ret;
250 
251 	if (!np && !pdata) {
252 		wl1251_error("no platform data");
253 		return -ENODEV;
254 	}
255 
256 	hw = wl1251_alloc_hw();
257 	if (IS_ERR(hw))
258 		return PTR_ERR(hw);
259 
260 	wl = hw->priv;
261 
262 	SET_IEEE80211_DEV(hw, &spi->dev);
263 	spi_set_drvdata(spi, wl);
264 	wl->if_priv = spi;
265 	wl->if_ops = &wl1251_spi_ops;
266 
267 	/* This is the only SPI value that we need to set here, the rest
268 	 * comes from the board-peripherals file
269 	 */
270 	spi->bits_per_word = 32;
271 
272 	ret = spi_setup(spi);
273 	if (ret < 0) {
274 		wl1251_error("spi_setup failed");
275 		goto out_free;
276 	}
277 
278 	if (np) {
279 		wl->use_eeprom = of_property_read_bool(np, "ti,wl1251-has-eeprom");
280 		wl->power_gpio = of_get_named_gpio(np, "ti,power-gpio", 0);
281 	} else if (pdata) {
282 		wl->power_gpio = pdata->power_gpio;
283 		wl->use_eeprom = pdata->use_eeprom;
284 	}
285 
286 	if (wl->power_gpio == -EPROBE_DEFER) {
287 		ret = -EPROBE_DEFER;
288 		goto out_free;
289 	}
290 
291 	if (gpio_is_valid(wl->power_gpio)) {
292 		ret = devm_gpio_request_one(&spi->dev, wl->power_gpio,
293 					GPIOF_OUT_INIT_LOW, "wl1251 power");
294 		if (ret) {
295 			wl1251_error("Failed to request gpio: %d\n", ret);
296 			goto out_free;
297 		}
298 	} else {
299 		wl1251_error("set power gpio missing in platform data");
300 		ret = -ENODEV;
301 		goto out_free;
302 	}
303 
304 	wl->irq = spi->irq;
305 	if (wl->irq < 0) {
306 		wl1251_error("irq missing in platform data");
307 		ret = -ENODEV;
308 		goto out_free;
309 	}
310 
311 	irq_set_status_flags(wl->irq, IRQ_NOAUTOEN);
312 	ret = devm_request_irq(&spi->dev, wl->irq, wl1251_irq, 0,
313 							DRIVER_NAME, wl);
314 	if (ret < 0) {
315 		wl1251_error("request_irq() failed: %d", ret);
316 		goto out_free;
317 	}
318 
319 	irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
320 
321 	wl->vio = devm_regulator_get(&spi->dev, "vio");
322 	if (IS_ERR(wl->vio)) {
323 		ret = PTR_ERR(wl->vio);
324 		wl1251_error("vio regulator missing: %d", ret);
325 		goto out_free;
326 	}
327 
328 	ret = regulator_enable(wl->vio);
329 	if (ret)
330 		goto out_free;
331 
332 	ret = wl1251_init_ieee80211(wl);
333 	if (ret)
334 		goto disable_regulator;
335 
336 	return 0;
337 
338 disable_regulator:
339 	regulator_disable(wl->vio);
340 out_free:
341 	ieee80211_free_hw(hw);
342 
343 	return ret;
344 }
345 
346 static int wl1251_spi_remove(struct spi_device *spi)
347 {
348 	struct wl1251 *wl = spi_get_drvdata(spi);
349 
350 	free_irq(wl->irq, wl);
351 	wl1251_free_hw(wl);
352 	regulator_disable(wl->vio);
353 
354 	return 0;
355 }
356 
357 static struct spi_driver wl1251_spi_driver = {
358 	.driver = {
359 		.name		= DRIVER_NAME,
360 		.owner		= THIS_MODULE,
361 	},
362 
363 	.probe		= wl1251_spi_probe,
364 	.remove		= wl1251_spi_remove,
365 };
366 
367 module_spi_driver(wl1251_spi_driver);
368 
369 MODULE_LICENSE("GPL");
370 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
371 MODULE_ALIAS("spi:wl1251");
372