1 /*
2 * B53 register access through SPI
3 *
4 * Copyright (C) 2011-2013 Jonas Gorski <jogo@openwrt.org>
5 *
6 * Permission to use, copy, modify, and/or distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <linux/unaligned.h>
20
21 #include <linux/delay.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/spi/spi.h>
25 #include <linux/platform_data/b53.h>
26
27 #include "b53_priv.h"
28
29 #define B53_SPI_DATA 0xf0
30
31 #define B53_SPI_STATUS 0xfe
32 #define B53_SPI_CMD_SPIF BIT(7)
33 #define B53_SPI_CMD_RACK BIT(5)
34
35 #define B53_SPI_CMD_READ 0x00
36 #define B53_SPI_CMD_WRITE 0x01
37 #define B53_SPI_CMD_NORMAL 0x60
38 #define B53_SPI_CMD_FAST 0x10
39
40 #define B53_SPI_PAGE_SELECT 0xff
41
b53_spi_read_reg(struct spi_device * spi,u8 reg,u8 * val,unsigned int len)42 static inline int b53_spi_read_reg(struct spi_device *spi, u8 reg, u8 *val,
43 unsigned int len)
44 {
45 u8 txbuf[2];
46
47 txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_READ;
48 txbuf[1] = reg;
49
50 return spi_write_then_read(spi, txbuf, 2, val, len);
51 }
52
b53_spi_clear_status(struct spi_device * spi)53 static inline int b53_spi_clear_status(struct spi_device *spi)
54 {
55 unsigned int i;
56 u8 rxbuf;
57 int ret;
58
59 for (i = 0; i < 10; i++) {
60 ret = b53_spi_read_reg(spi, B53_SPI_STATUS, &rxbuf, 1);
61 if (ret)
62 return ret;
63
64 if (!(rxbuf & B53_SPI_CMD_SPIF))
65 break;
66
67 mdelay(1);
68 }
69
70 if (i == 10)
71 return -EIO;
72
73 return 0;
74 }
75
b53_spi_set_page(struct spi_device * spi,u8 page)76 static inline int b53_spi_set_page(struct spi_device *spi, u8 page)
77 {
78 u8 txbuf[3];
79
80 txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
81 txbuf[1] = B53_SPI_PAGE_SELECT;
82 txbuf[2] = page;
83
84 return spi_write(spi, txbuf, sizeof(txbuf));
85 }
86
b53_prepare_reg_access(struct spi_device * spi,u8 page)87 static inline int b53_prepare_reg_access(struct spi_device *spi, u8 page)
88 {
89 int ret = b53_spi_clear_status(spi);
90
91 if (ret)
92 return ret;
93
94 return b53_spi_set_page(spi, page);
95 }
96
b53_spi_prepare_reg_read(struct spi_device * spi,u8 reg)97 static int b53_spi_prepare_reg_read(struct spi_device *spi, u8 reg)
98 {
99 u8 rxbuf;
100 int retry_count;
101 int ret;
102
103 ret = b53_spi_read_reg(spi, reg, &rxbuf, 1);
104 if (ret)
105 return ret;
106
107 for (retry_count = 0; retry_count < 10; retry_count++) {
108 ret = b53_spi_read_reg(spi, B53_SPI_STATUS, &rxbuf, 1);
109 if (ret)
110 return ret;
111
112 if (rxbuf & B53_SPI_CMD_RACK)
113 break;
114
115 mdelay(1);
116 }
117
118 if (retry_count == 10)
119 return -EIO;
120
121 return 0;
122 }
123
b53_spi_read(struct b53_device * dev,u8 page,u8 reg,u8 * data,unsigned int len)124 static int b53_spi_read(struct b53_device *dev, u8 page, u8 reg, u8 *data,
125 unsigned int len)
126 {
127 struct spi_device *spi = dev->priv;
128 int ret;
129
130 ret = b53_prepare_reg_access(spi, page);
131 if (ret)
132 return ret;
133
134 ret = b53_spi_prepare_reg_read(spi, reg);
135 if (ret)
136 return ret;
137
138 return b53_spi_read_reg(spi, B53_SPI_DATA, data, len);
139 }
140
b53_spi_read8(struct b53_device * dev,u8 page,u8 reg,u8 * val)141 static int b53_spi_read8(struct b53_device *dev, u8 page, u8 reg, u8 *val)
142 {
143 return b53_spi_read(dev, page, reg, val, 1);
144 }
145
b53_spi_read16(struct b53_device * dev,u8 page,u8 reg,u16 * val)146 static int b53_spi_read16(struct b53_device *dev, u8 page, u8 reg, u16 *val)
147 {
148 __le16 value;
149 int ret;
150
151 ret = b53_spi_read(dev, page, reg, (u8 *)&value, 2);
152
153 if (!ret)
154 *val = le16_to_cpu(value);
155
156 return ret;
157 }
158
b53_spi_read32(struct b53_device * dev,u8 page,u8 reg,u32 * val)159 static int b53_spi_read32(struct b53_device *dev, u8 page, u8 reg, u32 *val)
160 {
161 __le32 value;
162 int ret;
163
164 ret = b53_spi_read(dev, page, reg, (u8 *)&value, 4);
165
166 if (!ret)
167 *val = le32_to_cpu(value);
168
169 return ret;
170 }
171
b53_spi_read48(struct b53_device * dev,u8 page,u8 reg,u64 * val)172 static int b53_spi_read48(struct b53_device *dev, u8 page, u8 reg, u64 *val)
173 {
174 __le64 value;
175 int ret;
176
177 *val = 0;
178 ret = b53_spi_read(dev, page, reg, (u8 *)&value, 6);
179 if (!ret)
180 *val = le64_to_cpu(value);
181
182 return ret;
183 }
184
b53_spi_read64(struct b53_device * dev,u8 page,u8 reg,u64 * val)185 static int b53_spi_read64(struct b53_device *dev, u8 page, u8 reg, u64 *val)
186 {
187 __le64 value;
188 int ret;
189
190 ret = b53_spi_read(dev, page, reg, (u8 *)&value, 8);
191
192 if (!ret)
193 *val = le64_to_cpu(value);
194
195 return ret;
196 }
197
b53_spi_write8(struct b53_device * dev,u8 page,u8 reg,u8 value)198 static int b53_spi_write8(struct b53_device *dev, u8 page, u8 reg, u8 value)
199 {
200 struct spi_device *spi = dev->priv;
201 int ret;
202 u8 txbuf[3];
203
204 ret = b53_prepare_reg_access(spi, page);
205 if (ret)
206 return ret;
207
208 txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
209 txbuf[1] = reg;
210 txbuf[2] = value;
211
212 return spi_write(spi, txbuf, sizeof(txbuf));
213 }
214
b53_spi_write16(struct b53_device * dev,u8 page,u8 reg,u16 value)215 static int b53_spi_write16(struct b53_device *dev, u8 page, u8 reg, u16 value)
216 {
217 struct spi_device *spi = dev->priv;
218 int ret;
219 u8 txbuf[4];
220
221 ret = b53_prepare_reg_access(spi, page);
222 if (ret)
223 return ret;
224
225 txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
226 txbuf[1] = reg;
227 put_unaligned_le16(value, &txbuf[2]);
228
229 return spi_write(spi, txbuf, sizeof(txbuf));
230 }
231
b53_spi_write32(struct b53_device * dev,u8 page,u8 reg,u32 value)232 static int b53_spi_write32(struct b53_device *dev, u8 page, u8 reg, u32 value)
233 {
234 struct spi_device *spi = dev->priv;
235 int ret;
236 u8 txbuf[6];
237
238 ret = b53_prepare_reg_access(spi, page);
239 if (ret)
240 return ret;
241
242 txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
243 txbuf[1] = reg;
244 put_unaligned_le32(value, &txbuf[2]);
245
246 return spi_write(spi, txbuf, sizeof(txbuf));
247 }
248
b53_spi_write48(struct b53_device * dev,u8 page,u8 reg,u64 value)249 static int b53_spi_write48(struct b53_device *dev, u8 page, u8 reg, u64 value)
250 {
251 struct spi_device *spi = dev->priv;
252 int ret;
253 u8 txbuf[10];
254
255 ret = b53_prepare_reg_access(spi, page);
256 if (ret)
257 return ret;
258
259 txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
260 txbuf[1] = reg;
261 put_unaligned_le64(value, &txbuf[2]);
262
263 return spi_write(spi, txbuf, sizeof(txbuf) - 2);
264 }
265
b53_spi_write64(struct b53_device * dev,u8 page,u8 reg,u64 value)266 static int b53_spi_write64(struct b53_device *dev, u8 page, u8 reg, u64 value)
267 {
268 struct spi_device *spi = dev->priv;
269 int ret;
270 u8 txbuf[10];
271
272 ret = b53_prepare_reg_access(spi, page);
273 if (ret)
274 return ret;
275
276 txbuf[0] = B53_SPI_CMD_NORMAL | B53_SPI_CMD_WRITE;
277 txbuf[1] = reg;
278 put_unaligned_le64(value, &txbuf[2]);
279
280 return spi_write(spi, txbuf, sizeof(txbuf));
281 }
282
283 static const struct b53_io_ops b53_spi_ops = {
284 .read8 = b53_spi_read8,
285 .read16 = b53_spi_read16,
286 .read32 = b53_spi_read32,
287 .read48 = b53_spi_read48,
288 .read64 = b53_spi_read64,
289 .write8 = b53_spi_write8,
290 .write16 = b53_spi_write16,
291 .write32 = b53_spi_write32,
292 .write48 = b53_spi_write48,
293 .write64 = b53_spi_write64,
294 };
295
b53_spi_probe(struct spi_device * spi)296 static int b53_spi_probe(struct spi_device *spi)
297 {
298 struct b53_device *dev;
299 int ret;
300
301 dev = b53_switch_alloc(&spi->dev, &b53_spi_ops, spi);
302 if (!dev)
303 return -ENOMEM;
304
305 if (spi->dev.platform_data)
306 dev->pdata = spi->dev.platform_data;
307
308 ret = b53_switch_register(dev);
309 if (ret)
310 return ret;
311
312 spi_set_drvdata(spi, dev);
313
314 return 0;
315 }
316
b53_spi_remove(struct spi_device * spi)317 static void b53_spi_remove(struct spi_device *spi)
318 {
319 struct b53_device *dev = spi_get_drvdata(spi);
320
321 if (dev)
322 b53_switch_remove(dev);
323 }
324
b53_spi_shutdown(struct spi_device * spi)325 static void b53_spi_shutdown(struct spi_device *spi)
326 {
327 struct b53_device *dev = spi_get_drvdata(spi);
328
329 if (dev)
330 b53_switch_shutdown(dev);
331
332 spi_set_drvdata(spi, NULL);
333 }
334
335 static const struct of_device_id b53_spi_of_match[] = {
336 { .compatible = "brcm,bcm5325" },
337 { .compatible = "brcm,bcm5365" },
338 { .compatible = "brcm,bcm5395" },
339 { .compatible = "brcm,bcm5397" },
340 { .compatible = "brcm,bcm5398" },
341 { .compatible = "brcm,bcm53115" },
342 { .compatible = "brcm,bcm53125" },
343 { .compatible = "brcm,bcm53128" },
344 { /* sentinel */ }
345 };
346 MODULE_DEVICE_TABLE(of, b53_spi_of_match);
347
348 static const struct spi_device_id b53_spi_ids[] = {
349 { .name = "bcm5325" },
350 { .name = "bcm5365" },
351 { .name = "bcm5395" },
352 { .name = "bcm5397" },
353 { .name = "bcm5398" },
354 { .name = "bcm53115" },
355 { .name = "bcm53125" },
356 { .name = "bcm53128" },
357 { /* sentinel */ }
358 };
359 MODULE_DEVICE_TABLE(spi, b53_spi_ids);
360
361 static struct spi_driver b53_spi_driver = {
362 .driver = {
363 .name = "b53-switch",
364 .of_match_table = b53_spi_of_match,
365 },
366 .probe = b53_spi_probe,
367 .remove = b53_spi_remove,
368 .shutdown = b53_spi_shutdown,
369 .id_table = b53_spi_ids,
370 };
371
372 module_spi_driver(b53_spi_driver);
373
374 MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
375 MODULE_DESCRIPTION("B53 SPI access driver");
376 MODULE_LICENSE("Dual BSD/GPL");
377