1/*
2 * This file is part of wl1271
3 *
4 * Copyright (C) 2008-2009 Nokia Corporation
5 *
6 * Contact: Luciano Coelho <luciano.coelho@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 *
22 */
23
24#include <linux/interrupt.h>
25#include <linux/irq.h>
26#include <linux/module.h>
27#include <linux/crc7.h>
28#include <linux/spi/spi.h>
29#include <linux/wl12xx.h>
30#include <linux/platform_device.h>
31#include <linux/slab.h>
32
33#include "wl12xx.h"
34#include "wl12xx_80211.h"
35#include "io.h"
36
37#include "reg.h"
38
39#define WSPI_CMD_READ                 0x40000000
40#define WSPI_CMD_WRITE                0x00000000
41#define WSPI_CMD_FIXED                0x20000000
42#define WSPI_CMD_BYTE_LENGTH          0x1FFE0000
43#define WSPI_CMD_BYTE_LENGTH_OFFSET   17
44#define WSPI_CMD_BYTE_ADDR            0x0001FFFF
45
46#define WSPI_INIT_CMD_CRC_LEN       5
47
48#define WSPI_INIT_CMD_START         0x00
49#define WSPI_INIT_CMD_TX            0x40
50/* the extra bypass bit is sampled by the TNET as '1' */
51#define WSPI_INIT_CMD_BYPASS_BIT    0x80
52#define WSPI_INIT_CMD_FIXEDBUSY_LEN 0x07
53#define WSPI_INIT_CMD_EN_FIXEDBUSY  0x80
54#define WSPI_INIT_CMD_DIS_FIXEDBUSY 0x00
55#define WSPI_INIT_CMD_IOD           0x40
56#define WSPI_INIT_CMD_IP            0x20
57#define WSPI_INIT_CMD_CS            0x10
58#define WSPI_INIT_CMD_WS            0x08
59#define WSPI_INIT_CMD_WSPI          0x01
60#define WSPI_INIT_CMD_END           0x01
61
62#define WSPI_INIT_CMD_LEN           8
63
64#define HW_ACCESS_WSPI_FIXED_BUSY_LEN \
65		((WL1271_BUSY_WORD_LEN - 4) / sizeof(u32))
66#define HW_ACCESS_WSPI_INIT_CMD_MASK  0
67
68/* HW limitation: maximum possible chunk size is 4095 bytes */
69#define WSPI_MAX_CHUNK_SIZE    4092
70
71#define WSPI_MAX_NUM_OF_CHUNKS (WL1271_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE)
72
73struct wl12xx_spi_glue {
74	struct device *dev;
75	struct platform_device *core;
76};
77
78static void wl12xx_spi_reset(struct device *child)
79{
80	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
81	u8 *cmd;
82	struct spi_transfer t;
83	struct spi_message m;
84
85	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
86	if (!cmd) {
87		dev_err(child->parent,
88			"could not allocate cmd for spi reset\n");
89		return;
90	}
91
92	memset(&t, 0, sizeof(t));
93	spi_message_init(&m);
94
95	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
96
97	t.tx_buf = cmd;
98	t.len = WSPI_INIT_CMD_LEN;
99	spi_message_add_tail(&t, &m);
100
101	spi_sync(to_spi_device(glue->dev), &m);
102
103	kfree(cmd);
104}
105
106static void wl12xx_spi_init(struct device *child)
107{
108	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
109	u8 crc[WSPI_INIT_CMD_CRC_LEN], *cmd;
110	struct spi_transfer t;
111	struct spi_message m;
112
113	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
114	if (!cmd) {
115		dev_err(child->parent,
116			"could not allocate cmd for spi init\n");
117		return;
118	}
119
120	memset(crc, 0, sizeof(crc));
121	memset(&t, 0, sizeof(t));
122	spi_message_init(&m);
123
124	/*
125	 * Set WSPI_INIT_COMMAND
126	 * the data is being send from the MSB to LSB
127	 */
128	cmd[2] = 0xff;
129	cmd[3] = 0xff;
130	cmd[1] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
131	cmd[0] = 0;
132	cmd[7] = 0;
133	cmd[6] |= HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
134	cmd[6] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
135
136	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
137		cmd[5] |=  WSPI_INIT_CMD_DIS_FIXEDBUSY;
138	else
139		cmd[5] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
140
141	cmd[5] |= WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
142		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
143
144	crc[0] = cmd[1];
145	crc[1] = cmd[0];
146	crc[2] = cmd[7];
147	crc[3] = cmd[6];
148	crc[4] = cmd[5];
149
150	cmd[4] |= crc7(0, crc, WSPI_INIT_CMD_CRC_LEN) << 1;
151	cmd[4] |= WSPI_INIT_CMD_END;
152
153	t.tx_buf = cmd;
154	t.len = WSPI_INIT_CMD_LEN;
155	spi_message_add_tail(&t, &m);
156
157	spi_sync(to_spi_device(glue->dev), &m);
158	kfree(cmd);
159}
160
161#define WL1271_BUSY_WORD_TIMEOUT 1000
162
163static int wl12xx_spi_read_busy(struct device *child)
164{
165	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
166	struct wl1271 *wl = dev_get_drvdata(child);
167	struct spi_transfer t[1];
168	struct spi_message m;
169	u32 *busy_buf;
170	int num_busy_bytes = 0;
171
172	/*
173	 * Read further busy words from SPI until a non-busy word is
174	 * encountered, then read the data itself into the buffer.
175	 */
176
177	num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
178	busy_buf = wl->buffer_busyword;
179	while (num_busy_bytes) {
180		num_busy_bytes--;
181		spi_message_init(&m);
182		memset(t, 0, sizeof(t));
183		t[0].rx_buf = busy_buf;
184		t[0].len = sizeof(u32);
185		t[0].cs_change = true;
186		spi_message_add_tail(&t[0], &m);
187		spi_sync(to_spi_device(glue->dev), &m);
188
189		if (*busy_buf & 0x1)
190			return 0;
191	}
192
193	/* The SPI bus is unresponsive, the read failed. */
194	dev_err(child->parent, "SPI read busy-word timeout!\n");
195	return -ETIMEDOUT;
196}
197
198static void wl12xx_spi_raw_read(struct device *child, int addr, void *buf,
199				size_t len, bool fixed)
200{
201	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
202	struct wl1271 *wl = dev_get_drvdata(child);
203	struct spi_transfer t[2];
204	struct spi_message m;
205	u32 *busy_buf;
206	u32 *cmd;
207	u32 chunk_len;
208
209	while (len > 0) {
210		chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
211
212		cmd = &wl->buffer_cmd;
213		busy_buf = wl->buffer_busyword;
214
215		*cmd = 0;
216		*cmd |= WSPI_CMD_READ;
217		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
218			WSPI_CMD_BYTE_LENGTH;
219		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
220
221		if (fixed)
222			*cmd |= WSPI_CMD_FIXED;
223
224		spi_message_init(&m);
225		memset(t, 0, sizeof(t));
226
227		t[0].tx_buf = cmd;
228		t[0].len = 4;
229		t[0].cs_change = true;
230		spi_message_add_tail(&t[0], &m);
231
232		/* Busy and non busy words read */
233		t[1].rx_buf = busy_buf;
234		t[1].len = WL1271_BUSY_WORD_LEN;
235		t[1].cs_change = true;
236		spi_message_add_tail(&t[1], &m);
237
238		spi_sync(to_spi_device(glue->dev), &m);
239
240		if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
241		    wl12xx_spi_read_busy(child)) {
242			memset(buf, 0, chunk_len);
243			return;
244		}
245
246		spi_message_init(&m);
247		memset(t, 0, sizeof(t));
248
249		t[0].rx_buf = buf;
250		t[0].len = chunk_len;
251		t[0].cs_change = true;
252		spi_message_add_tail(&t[0], &m);
253
254		spi_sync(to_spi_device(glue->dev), &m);
255
256		if (!fixed)
257			addr += chunk_len;
258		buf += chunk_len;
259		len -= chunk_len;
260	}
261}
262
263static void wl12xx_spi_raw_write(struct device *child, int addr, void *buf,
264				 size_t len, bool fixed)
265{
266	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
267	struct spi_transfer t[2 * WSPI_MAX_NUM_OF_CHUNKS];
268	struct spi_message m;
269	u32 commands[WSPI_MAX_NUM_OF_CHUNKS];
270	u32 *cmd;
271	u32 chunk_len;
272	int i;
273
274	WARN_ON(len > WL1271_AGGR_BUFFER_SIZE);
275
276	spi_message_init(&m);
277	memset(t, 0, sizeof(t));
278
279	cmd = &commands[0];
280	i = 0;
281	while (len > 0) {
282		chunk_len = min((size_t)WSPI_MAX_CHUNK_SIZE, len);
283
284		*cmd = 0;
285		*cmd |= WSPI_CMD_WRITE;
286		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
287			WSPI_CMD_BYTE_LENGTH;
288		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
289
290		if (fixed)
291			*cmd |= WSPI_CMD_FIXED;
292
293		t[i].tx_buf = cmd;
294		t[i].len = sizeof(*cmd);
295		spi_message_add_tail(&t[i++], &m);
296
297		t[i].tx_buf = buf;
298		t[i].len = chunk_len;
299		spi_message_add_tail(&t[i++], &m);
300
301		if (!fixed)
302			addr += chunk_len;
303		buf += chunk_len;
304		len -= chunk_len;
305		cmd++;
306	}
307
308	spi_sync(to_spi_device(glue->dev), &m);
309}
310
311static struct wl1271_if_operations spi_ops = {
312	.read		= wl12xx_spi_raw_read,
313	.write		= wl12xx_spi_raw_write,
314	.reset		= wl12xx_spi_reset,
315	.init		= wl12xx_spi_init,
316	.set_block_size = NULL,
317};
318
319static int __devinit wl1271_probe(struct spi_device *spi)
320{
321	struct wl12xx_spi_glue *glue;
322	struct wl12xx_platform_data *pdata;
323	struct resource res[1];
324	int ret = -ENOMEM;
325
326	pdata = spi->dev.platform_data;
327	if (!pdata) {
328		dev_err(&spi->dev, "no platform data\n");
329		return -ENODEV;
330	}
331
332	pdata->ops = &spi_ops;
333
334	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
335	if (!glue) {
336		dev_err(&spi->dev, "can't allocate glue\n");
337		goto out;
338	}
339
340	glue->dev = &spi->dev;
341
342	spi_set_drvdata(spi, glue);
343
344	/* This is the only SPI value that we need to set here, the rest
345	 * comes from the board-peripherals file */
346	spi->bits_per_word = 32;
347
348	ret = spi_setup(spi);
349	if (ret < 0) {
350		dev_err(glue->dev, "spi_setup failed\n");
351		goto out_free_glue;
352	}
353
354	glue->core = platform_device_alloc("wl12xx", -1);
355	if (!glue->core) {
356		dev_err(glue->dev, "can't allocate platform_device\n");
357		ret = -ENOMEM;
358		goto out_free_glue;
359	}
360
361	glue->core->dev.parent = &spi->dev;
362
363	memset(res, 0x00, sizeof(res));
364
365	res[0].start = spi->irq;
366	res[0].flags = IORESOURCE_IRQ;
367	res[0].name = "irq";
368
369	ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
370	if (ret) {
371		dev_err(glue->dev, "can't add resources\n");
372		goto out_dev_put;
373	}
374
375	ret = platform_device_add_data(glue->core, pdata, sizeof(*pdata));
376	if (ret) {
377		dev_err(glue->dev, "can't add platform data\n");
378		goto out_dev_put;
379	}
380
381	ret = platform_device_add(glue->core);
382	if (ret) {
383		dev_err(glue->dev, "can't register platform device\n");
384		goto out_dev_put;
385	}
386
387	return 0;
388
389out_dev_put:
390	platform_device_put(glue->core);
391
392out_free_glue:
393	kfree(glue);
394out:
395	return ret;
396}
397
398static int __devexit wl1271_remove(struct spi_device *spi)
399{
400	struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
401
402	platform_device_del(glue->core);
403	platform_device_put(glue->core);
404	kfree(glue);
405
406	return 0;
407}
408
409
410static struct spi_driver wl1271_spi_driver = {
411	.driver = {
412		.name		= "wl1271_spi",
413		.owner		= THIS_MODULE,
414	},
415
416	.probe		= wl1271_probe,
417	.remove		= __devexit_p(wl1271_remove),
418};
419
420static int __init wl1271_init(void)
421{
422	return spi_register_driver(&wl1271_spi_driver);
423}
424
425static void __exit wl1271_exit(void)
426{
427	spi_unregister_driver(&wl1271_spi_driver);
428}
429
430module_init(wl1271_init);
431module_exit(wl1271_exit);
432
433MODULE_LICENSE("GPL");
434MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
435MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
436MODULE_FIRMWARE(WL127X_FW_NAME);
437MODULE_FIRMWARE(WL128X_FW_NAME);
438MODULE_ALIAS("spi:wl1271");
439