xref: /openbmc/linux/drivers/net/wireless/ti/wl1251/spi.c (revision 54cbac81)
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 
30 #include "wl1251.h"
31 #include "reg.h"
32 #include "spi.h"
33 
34 static irqreturn_t wl1251_irq(int irq, void *cookie)
35 {
36 	struct wl1251 *wl;
37 
38 	wl1251_debug(DEBUG_IRQ, "IRQ");
39 
40 	wl = cookie;
41 
42 	ieee80211_queue_work(wl->hw, &wl->irq_work);
43 
44 	return IRQ_HANDLED;
45 }
46 
47 static struct spi_device *wl_to_spi(struct wl1251 *wl)
48 {
49 	return wl->if_priv;
50 }
51 
52 static void wl1251_spi_reset(struct wl1251 *wl)
53 {
54 	u8 *cmd;
55 	struct spi_transfer t;
56 	struct spi_message m;
57 
58 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
59 	if (!cmd) {
60 		wl1251_error("could not allocate cmd for spi reset");
61 		return;
62 	}
63 
64 	memset(&t, 0, sizeof(t));
65 	spi_message_init(&m);
66 
67 	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
68 
69 	t.tx_buf = cmd;
70 	t.len = WSPI_INIT_CMD_LEN;
71 	spi_message_add_tail(&t, &m);
72 
73 	spi_sync(wl_to_spi(wl), &m);
74 
75 	wl1251_dump(DEBUG_SPI, "spi reset -> ", cmd, WSPI_INIT_CMD_LEN);
76 
77 	kfree(cmd);
78 }
79 
80 static void wl1251_spi_wake(struct wl1251 *wl)
81 {
82 	u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
83 	struct spi_transfer t;
84 	struct spi_message m;
85 
86 	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
87 	if (!cmd) {
88 		wl1251_error("could not allocate cmd for spi init");
89 		return;
90 	}
91 
92 	memset(crc, 0, sizeof(crc));
93 	memset(&t, 0, sizeof(t));
94 	spi_message_init(&m);
95 
96 	/*
97 	 * Set WSPI_INIT_COMMAND
98 	 * the data is being send from the MSB to LSB
99 	 */
100 	cmd[2] = 0xff;
101 	cmd[3] = 0xff;
102 	cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
103 	cmd[0] = 0;
104 	cmd[7] = 0;
105 	cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
106 	cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
107 
108 	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
109 		cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
110 	else
111 		cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
112 
113 	cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
114 		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
115 
116 	crc[0] = cmd[1];
117 	crc[1] = cmd[0];
118 	crc[2] = cmd[7];
119 	crc[3] = cmd[6];
120 	crc[4] = cmd[5];
121 
122 	cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
123 	cmd[4] |= WSPI_INIT_CMD_END;
124 
125 	t.tx_buf = cmd;
126 	t.len = WSPI_INIT_CMD_LEN;
127 	spi_message_add_tail(&t, &m);
128 
129 	spi_sync(wl_to_spi(wl), &m);
130 
131 	wl1251_dump(DEBUG_SPI, "spi init -> ", cmd, WSPI_INIT_CMD_LEN);
132 
133 	kfree(cmd);
134 }
135 
136 static void wl1251_spi_reset_wake(struct wl1251 *wl)
137 {
138 	wl1251_spi_reset(wl);
139 	wl1251_spi_wake(wl);
140 }
141 
142 static void wl1251_spi_read(struct wl1251 *wl, int addr, void *buf,
143 			    size_t len)
144 {
145 	struct spi_transfer t[3];
146 	struct spi_message m;
147 	u8 *busy_buf;
148 	u32 *cmd;
149 
150 	cmd = &wl->buffer_cmd;
151 	busy_buf = wl->buffer_busyword;
152 
153 	*cmd = 0;
154 	*cmd |= WSPI_CMD_READ;
155 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
156 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
157 
158 	spi_message_init(&m);
159 	memset(t, 0, sizeof(t));
160 
161 	t[0].tx_buf = cmd;
162 	t[0].len = 4;
163 	spi_message_add_tail(&t[0], &m);
164 
165 	/* Busy and non busy words read */
166 	t[1].rx_buf = busy_buf;
167 	t[1].len = WL1251_BUSY_WORD_LEN;
168 	spi_message_add_tail(&t[1], &m);
169 
170 	t[2].rx_buf = buf;
171 	t[2].len = len;
172 	spi_message_add_tail(&t[2], &m);
173 
174 	spi_sync(wl_to_spi(wl), &m);
175 
176 	/* FIXME: check busy words */
177 
178 	wl1251_dump(DEBUG_SPI, "spi_read cmd -> ", cmd, sizeof(*cmd));
179 	wl1251_dump(DEBUG_SPI, "spi_read buf <- ", buf, len);
180 }
181 
182 static void wl1251_spi_write(struct wl1251 *wl, int addr, void *buf,
183 			     size_t len)
184 {
185 	struct spi_transfer t[2];
186 	struct spi_message m;
187 	u32 *cmd;
188 
189 	cmd = &wl->buffer_cmd;
190 
191 	*cmd = 0;
192 	*cmd |= WSPI_CMD_WRITE;
193 	*cmd |= (len << WSPI_CMD_BYTE_LENGTH_OFFSET) & WSPI_CMD_BYTE_LENGTH;
194 	*cmd |= addr & WSPI_CMD_BYTE_ADDR;
195 
196 	spi_message_init(&m);
197 	memset(t, 0, sizeof(t));
198 
199 	t[0].tx_buf = cmd;
200 	t[0].len = sizeof(*cmd);
201 	spi_message_add_tail(&t[0], &m);
202 
203 	t[1].tx_buf = buf;
204 	t[1].len = len;
205 	spi_message_add_tail(&t[1], &m);
206 
207 	spi_sync(wl_to_spi(wl), &m);
208 
209 	wl1251_dump(DEBUG_SPI, "spi_write cmd -> ", cmd, sizeof(*cmd));
210 	wl1251_dump(DEBUG_SPI, "spi_write buf -> ", buf, len);
211 }
212 
213 static void wl1251_spi_enable_irq(struct wl1251 *wl)
214 {
215 	return enable_irq(wl->irq);
216 }
217 
218 static void wl1251_spi_disable_irq(struct wl1251 *wl)
219 {
220 	return disable_irq(wl->irq);
221 }
222 
223 static int wl1251_spi_set_power(struct wl1251 *wl, bool enable)
224 {
225 	if (wl->set_power)
226 		wl->set_power(enable);
227 
228 	return 0;
229 }
230 
231 static const struct wl1251_if_operations wl1251_spi_ops = {
232 	.read = wl1251_spi_read,
233 	.write = wl1251_spi_write,
234 	.reset = wl1251_spi_reset_wake,
235 	.enable_irq = wl1251_spi_enable_irq,
236 	.disable_irq = wl1251_spi_disable_irq,
237 	.power = wl1251_spi_set_power,
238 };
239 
240 static int wl1251_spi_probe(struct spi_device *spi)
241 {
242 	struct wl12xx_platform_data *pdata;
243 	struct ieee80211_hw *hw;
244 	struct wl1251 *wl;
245 	int ret;
246 
247 	pdata = spi->dev.platform_data;
248 	if (!pdata) {
249 		wl1251_error("no platform data");
250 		return -ENODEV;
251 	}
252 
253 	hw = wl1251_alloc_hw();
254 	if (IS_ERR(hw))
255 		return PTR_ERR(hw);
256 
257 	wl = hw->priv;
258 
259 	SET_IEEE80211_DEV(hw, &spi->dev);
260 	dev_set_drvdata(&spi->dev, wl);
261 	wl->if_priv = spi;
262 	wl->if_ops = &wl1251_spi_ops;
263 
264 	/* This is the only SPI value that we need to set here, the rest
265 	 * comes from the board-peripherals file */
266 	spi->bits_per_word = 32;
267 
268 	ret = spi_setup(spi);
269 	if (ret < 0) {
270 		wl1251_error("spi_setup failed");
271 		goto out_free;
272 	}
273 
274 	wl->set_power = pdata->set_power;
275 	if (!wl->set_power) {
276 		wl1251_error("set power function missing in platform data");
277 		return -ENODEV;
278 	}
279 
280 	wl->irq = spi->irq;
281 	if (wl->irq < 0) {
282 		wl1251_error("irq missing in platform data");
283 		return -ENODEV;
284 	}
285 
286 	wl->use_eeprom = pdata->use_eeprom;
287 
288 	irq_set_status_flags(wl->irq, IRQ_NOAUTOEN);
289 	ret = request_irq(wl->irq, wl1251_irq, 0, DRIVER_NAME, wl);
290 	if (ret < 0) {
291 		wl1251_error("request_irq() failed: %d", ret);
292 		goto out_free;
293 	}
294 
295 	irq_set_irq_type(wl->irq, IRQ_TYPE_EDGE_RISING);
296 
297 	ret = wl1251_init_ieee80211(wl);
298 	if (ret)
299 		goto out_irq;
300 
301 	return 0;
302 
303  out_irq:
304 	free_irq(wl->irq, wl);
305 
306  out_free:
307 	ieee80211_free_hw(hw);
308 
309 	return ret;
310 }
311 
312 static int wl1251_spi_remove(struct spi_device *spi)
313 {
314 	struct wl1251 *wl = dev_get_drvdata(&spi->dev);
315 
316 	free_irq(wl->irq, wl);
317 	wl1251_free_hw(wl);
318 
319 	return 0;
320 }
321 
322 static struct spi_driver wl1251_spi_driver = {
323 	.driver = {
324 		.name		= DRIVER_NAME,
325 		.owner		= THIS_MODULE,
326 	},
327 
328 	.probe		= wl1251_spi_probe,
329 	.remove		= wl1251_spi_remove,
330 };
331 
332 static int __init wl1251_spi_init(void)
333 {
334 	int ret;
335 
336 	ret = spi_register_driver(&wl1251_spi_driver);
337 	if (ret < 0) {
338 		wl1251_error("failed to register spi driver: %d", ret);
339 		goto out;
340 	}
341 
342 out:
343 	return ret;
344 }
345 
346 static void __exit wl1251_spi_exit(void)
347 {
348 	spi_unregister_driver(&wl1251_spi_driver);
349 
350 	wl1251_notice("unloaded");
351 }
352 
353 module_init(wl1251_spi_init);
354 module_exit(wl1251_spi_exit);
355 
356 MODULE_LICENSE("GPL");
357 MODULE_AUTHOR("Kalle Valo <kvalo@adurom.com>");
358 MODULE_ALIAS("spi:wl1251");
359