xref: /openbmc/linux/drivers/net/wireless/ti/wl1251/spi.c (revision f3539c12)
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/swab.h>
27 #include <linux/crc7.h>
28 #include <linux/spi/spi.h>
29 #include <linux/wl12xx.h>
30 #include <linux/gpio.h>
31 #include <linux/of.h>
32 #include <linux/of_gpio.h>
33 #include <linux/regulator/consumer.h>
34 
35 #include "wl1251.h"
36 #include "reg.h"
37 #include "spi.h"
38 
39 static irqreturn_t wl1251_irq(int irq, void *cookie)
40 {
41 	struct wl1251 *wl;
42 
43 	wl1251_debug(DEBUG_IRQ, "IRQ");
44 
45 	wl = cookie;
46 
47 	ieee80211_queue_work(wl->hw, &wl->irq_work);
48 
49 	return IRQ_HANDLED;
50 }
51 
52 static struct spi_device *wl_to_spi(struct wl1251 *wl)
53 {
54 	return wl->if_priv;
55 }
56 
57 static void wl1251_spi_reset(struct wl1251 *wl)
58 {
59 	u8 *cmd;
60 	struct spi_transfer t;
61 	struct spi_message m;
62 
63 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
64 	if (!cmd) {
65 		wl1251_error("could not allocate cmd for spi reset");
66 		return;
67 	}
68 
69 	memset(&t, 0, sizeof(t));
70 	spi_message_init(&m);
71 
72 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
73 
74 	t.tx_buf = cmd;
75 	t.len = WSPI_INIT_CMD_LEN;
76 	spi_message_add_tail(&t, &m);
77 
78 	spi_sync(wl_to_spi(wl), &m);
79 
80 	wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
81 
82 	kfree(cmd);
83 }
84 
85 static void wl1251_spi_wake(struct wl1251 *wl)
86 {
87 	struct spi_transfer t;
88 	struct spi_message m;
89 	u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
90 
91 	if (!cmd) {
92 		wl1251_error("could not allocate cmd for spi init");
93 		return;
94 	}
95 
96 	memset(&t, 0, sizeof(t));
97 	spi_message_init(&m);
98 
99 	/* Set WSPI_INIT_COMMAND
100 	 * the data is being send from the MSB to LSB
101 	 */
102 	cmd[0] = 0xff;
103 	cmd[1] = 0xff;
104 	cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
105 	cmd[3] = 0;
106 	cmd[4] = 0;
107 	cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
108 	cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
109 
110 	cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
111 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
112 
113 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
114 		cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
115 	else
116 		cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
117 
118 	cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
119 	/*
120 	 * The above is the logical order; it must actually be stored
121 	 * in the buffer byte-swapped.
122 	 */
123 	__swab32s((u32 *)cmd);
124 	__swab32s((u32 *)cmd+1);
125 
126 	t.tx_buf = cmd;
127 	t.len = WSPI_INIT_CMD_LEN;
128 	spi_message_add_tail(&t, &m);
129 
130 	spi_sync(wl_to_spi(wl), &m);
131 
132 	wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
133 
134 	kfree(cmd);
135 }
136 
137 static void wl1251_spi_reset_wake(struct wl1251 *wl)
138 {
139 	wl1251_spi_reset(wl);
140 	wl1251_spi_wake(wl);
141 }
142 
143 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
144 			    size_t len)
145 {
146 	struct spi_transfer t[3];
147 	struct spi_message m;
148 	u8 *busy_buf;
149 	u32 *cmd;
150 
151 	cmd = &wl->buffer_cmd;
152 	busy_buf = wl->buffer_busyword;
153 
154 	*cmd = 0;
155 	*cmd |= WSPI_CMD_READ;
156 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
157 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
158 
159 	spi_message_init(&m);
160 	memset(t, 0, sizeof(t));
161 
162 	t[0].tx_buf = cmd;
163 	t[0].len = 4;
164 	spi_message_add_tail(&t[0], &m);
165 
166 	/* Busy and non busy words read */
167 	t[1].rx_buf = busy_buf;
168 	t[1].len = WL1251_BUSY_WORD_LEN;
169 	spi_message_add_tail(&t[1], &m);
170 
171 	t[2].rx_buf = buf;
172 	t[2].len = len;
173 	spi_message_add_tail(&t[2], &m);
174 
175 	spi_sync(wl_to_spi(wl), &m);
176 
177 	/* FIXME: check busy words */
178 
179 	wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
180 	wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
181 }
182 
183 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
184 			     size_t len)
185 {
186 	struct spi_transfer t[2];
187 	struct spi_message m;
188 	u32 *cmd;
189 
190 	cmd = &wl->buffer_cmd;
191 
192 	*cmd = 0;
193 	*cmd |= WSPI_CMD_WRITE;
194 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
195 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
196 
197 	spi_message_init(&m);
198 	memset(t, 0, sizeof(t));
199 
200 	t[0].tx_buf = cmd;
201 	t[0].len = sizeof(*cmd);
202 	spi_message_add_tail(&t[0], &m);
203 
204 	t[1].tx_buf = buf;
205 	t[1].len = len;
206 	spi_message_add_tail(&t[1], &m);
207 
208 	spi_sync(wl_to_spi(wl), &m);
209 
210 	wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
211 	wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
212 }
213 
214 static void wl1251_spi_enable_irq(struct wl1251 *wl)
215 {
216 	return enable_irq(wl->irq);
217 }
218 
219 static void wl1251_spi_disable_irq(struct wl1251 *wl)
220 {
221 	return disable_irq(wl->irq);
222 }
223 
224 static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
225 {
226 	if (gpio_is_valid(wl->power_gpio))
227 		gpio_set_value(wl->power_gpio, enable);
228 
229 	return 0;
230 }
231 
232 static const struct wl1251_if_operations wl1251_spi_ops = {
233 	.read = wl1251_spi_read,
234 	.write = wl1251_spi_write,
235 	.reset = wl1251_spi_reset_wake,
236 	.enable_irq = wl1251_spi_enable_irq,
237 	.disable_irq = wl1251_spi_disable_irq,
238 	.power = wl1251_spi_set_power,
239 };
240 
241 static int wl1251_spi_probe(struct spi_device *spi)
242 {
243 	struct wl1251_platform_data *pdata = dev_get_platdata(&spi->dev);
244 	struct device_node *np = spi->dev.of_node;
245 	struct ieee80211_hw *hw;
246 	struct wl1251 *wl;
247 	int ret;
248 
249 	if (!np && !pdata) {
250 		wl1251_error("no platform data");
251 		return -ENODEV;
252 	}
253 
254 	hw = wl1251_alloc_hw();
255 	if (IS_ERR(hw))
256 		return PTR_ERR(hw);
257 
258 	wl = hw->priv;
259 
260 	SET_IEEE80211_DEV(hw, &spi->dev);
261 	spi_set_drvdata(spi, wl);
262 	wl->if_priv = spi;
263 	wl->if_ops = &wl1251_spi_ops;
264 
265 	/* This is the only SPI value that we need to set here, the rest
266 	 * comes from the board-peripherals file
267 	 */
268 	spi->bits_per_word = 32;
269 
270 	ret = spi_setup(spi);
271 	if (ret < 0) {
272 		wl1251_error("spi_setup failed");
273 		goto out_free;
274 	}
275 
276 	if (np) {
277 		wl->use_eeprom = of_property_read_bool(np, "ti,wl1251-has-eeprom");
278 		wl->power_gpio = of_get_named_gpio(np, "ti,power-gpio", 0);
279 	} else if (pdata) {
280 		wl->power_gpio = pdata->power_gpio;
281 		wl->use_eeprom = pdata->use_eeprom;
282 	}
283 
284 	if (wl->power_gpio == -EPROBE_DEFER) {
285 		ret = -EPROBE_DEFER;
286 		goto out_free;
287 	}
288 
289 	if (gpio_is_valid(wl->power_gpio)) {
290 		ret = devm_gpio_request_one(&spi->dev, wl->power_gpio,
291 					GPIOF_OUT_INIT_LOW, "wl1251 power");
292 		if (ret) {
293 			wl1251_error("Failed to request gpio: %d\n", ret);
294 			goto out_free;
295 		}
296 	} else {
297 		wl1251_error("set power gpio missing in platform data");
298 		ret = -ENODEV;
299 		goto out_free;
300 	}
301 
302 	wl->irq = spi->irq;
303 	if (wl->irq < 0) {
304 		wl1251_error("irq missing in platform data");
305 		ret = -ENODEV;
306 		goto out_free;
307 	}
308 
309 	irq_set_status_flags(wl->irq, IRQ_NOAUTOEN);
310 	ret = devm_request_irq(&spi->dev, wl->irq, wl1251_irq, 0,
311 							DRIVER_NAME, wl);
312 	if (ret < 0) {
313 		wl1251_error("request_irq() failed: %d", ret);
314 		goto out_free;
315 	}
316 
317 	irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
318 
319 	wl->vio = devm_regulator_get(&spi->dev, "vio");
320 	if (IS_ERR(wl->vio)) {
321 		ret = PTR_ERR(wl->vio);
322 		wl1251_error("vio regulator missing: %d", ret);
323 		goto out_free;
324 	}
325 
326 	ret = regulator_enable(wl->vio);
327 	if (ret)
328 		goto out_free;
329 
330 	ret = wl1251_init_ieee80211(wl);
331 	if (ret)
332 		goto disable_regulator;
333 
334 	return 0;
335 
336 disable_regulator:
337 	regulator_disable(wl->vio);
338 out_free:
339 	ieee80211_free_hw(hw);
340 
341 	return ret;
342 }
343 
344 static int wl1251_spi_remove(struct spi_device *spi)
345 {
346 	struct wl1251 *wl = spi_get_drvdata(spi);
347 
348 	wl1251_free_hw(wl);
349 	regulator_disable(wl->vio);
350 
351 	return 0;
352 }
353 
354 static struct spi_driver wl1251_spi_driver = {
355 	.driver = {
356 		.name		= DRIVER_NAME,
357 	},
358 
359 	.probe		= wl1251_spi_probe,
360 	.remove		= wl1251_spi_remove,
361 };
362 
363 module_spi_driver(wl1251_spi_driver);
364 
365 MODULE_LICENSE("GPL");
366 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
367 MODULE_ALIAS("spi:wl1251");
368