1 /**
2 * Register map access API - ENCX24J600 support
3 *
4 * Copyright 2015 Gridpoint
5 *
6 * Author: Jon Ringle <jringle@gridpoint.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/delay.h>
14 #include <linux/errno.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/netdevice.h>
18 #include <linux/regmap.h>
19 #include <linux/spi/spi.h>
20
21 #include "encx24j600_hw.h"
22
is_bits_set(int value,int mask)23 static inline bool is_bits_set(int value, int mask)
24 {
25 return (value & mask) == mask;
26 }
27
encx24j600_switch_bank(struct encx24j600_context * ctx,int bank)28 static int encx24j600_switch_bank(struct encx24j600_context *ctx,
29 int bank)
30 {
31 int ret = 0;
32 int bank_opcode = BANK_SELECT(bank);
33
34 ret = spi_write(ctx->spi, &bank_opcode, 1);
35 if (ret == 0)
36 ctx->bank = bank;
37
38 return ret;
39 }
40
encx24j600_cmdn(struct encx24j600_context * ctx,u8 opcode,const void * buf,size_t len)41 static int encx24j600_cmdn(struct encx24j600_context *ctx, u8 opcode,
42 const void *buf, size_t len)
43 {
44 struct spi_message m;
45 struct spi_transfer t[2] = { { .tx_buf = &opcode, .len = 1, },
46 { .tx_buf = buf, .len = len }, };
47 spi_message_init(&m);
48 spi_message_add_tail(&t[0], &m);
49 spi_message_add_tail(&t[1], &m);
50
51 return spi_sync(ctx->spi, &m);
52 }
53
regmap_lock_mutex(void * context)54 static void regmap_lock_mutex(void *context)
55 {
56 struct encx24j600_context *ctx = context;
57
58 mutex_lock(&ctx->mutex);
59 }
60
regmap_unlock_mutex(void * context)61 static void regmap_unlock_mutex(void *context)
62 {
63 struct encx24j600_context *ctx = context;
64
65 mutex_unlock(&ctx->mutex);
66 }
67
regmap_encx24j600_sfr_read(void * context,u8 reg,u8 * val,size_t len)68 static int regmap_encx24j600_sfr_read(void *context, u8 reg, u8 *val,
69 size_t len)
70 {
71 struct encx24j600_context *ctx = context;
72 u8 banked_reg = reg & ADDR_MASK;
73 u8 bank = ((reg & BANK_MASK) >> BANK_SHIFT);
74 u8 cmd = RCRU;
75 int ret = 0;
76 int i = 0;
77 u8 tx_buf[2];
78
79 if (reg < 0x80) {
80 cmd = RCRCODE | banked_reg;
81 if ((banked_reg < 0x16) && (ctx->bank != bank))
82 ret = encx24j600_switch_bank(ctx, bank);
83 if (unlikely(ret))
84 return ret;
85 } else {
86 /* Translate registers that are more effecient using
87 * 3-byte SPI commands
88 */
89 switch (reg) {
90 case EGPRDPT:
91 cmd = RGPRDPT; break;
92 case EGPWRPT:
93 cmd = RGPWRPT; break;
94 case ERXRDPT:
95 cmd = RRXRDPT; break;
96 case ERXWRPT:
97 cmd = RRXWRPT; break;
98 case EUDARDPT:
99 cmd = RUDARDPT; break;
100 case EUDAWRPT:
101 cmd = RUDAWRPT; break;
102 case EGPDATA:
103 case ERXDATA:
104 case EUDADATA:
105 default:
106 return -EINVAL;
107 }
108 }
109
110 tx_buf[i++] = cmd;
111 if (cmd == RCRU)
112 tx_buf[i++] = reg;
113
114 ret = spi_write_then_read(ctx->spi, tx_buf, i, val, len);
115
116 return ret;
117 }
118
regmap_encx24j600_sfr_update(struct encx24j600_context * ctx,u8 reg,u8 * val,size_t len,u8 unbanked_cmd,u8 banked_code)119 static int regmap_encx24j600_sfr_update(struct encx24j600_context *ctx,
120 u8 reg, u8 *val, size_t len,
121 u8 unbanked_cmd, u8 banked_code)
122 {
123 u8 banked_reg = reg & ADDR_MASK;
124 u8 bank = ((reg & BANK_MASK) >> BANK_SHIFT);
125 u8 cmd = unbanked_cmd;
126 struct spi_message m;
127 struct spi_transfer t[3] = { { .tx_buf = &cmd, .len = sizeof(cmd), },
128 { .tx_buf = ®, .len = sizeof(reg), },
129 { .tx_buf = val, .len = len }, };
130
131 if (reg < 0x80) {
132 int ret = 0;
133
134 cmd = banked_code | banked_reg;
135 if ((banked_reg < 0x16) && (ctx->bank != bank))
136 ret = encx24j600_switch_bank(ctx, bank);
137 if (unlikely(ret))
138 return ret;
139 } else {
140 /* Translate registers that are more effecient using
141 * 3-byte SPI commands
142 */
143 switch (reg) {
144 case EGPRDPT:
145 cmd = WGPRDPT; break;
146 case EGPWRPT:
147 cmd = WGPWRPT; break;
148 case ERXRDPT:
149 cmd = WRXRDPT; break;
150 case ERXWRPT:
151 cmd = WRXWRPT; break;
152 case EUDARDPT:
153 cmd = WUDARDPT; break;
154 case EUDAWRPT:
155 cmd = WUDAWRPT; break;
156 case EGPDATA:
157 case ERXDATA:
158 case EUDADATA:
159 default:
160 return -EINVAL;
161 }
162 }
163
164 spi_message_init(&m);
165 spi_message_add_tail(&t[0], &m);
166
167 if (cmd == unbanked_cmd) {
168 t[1].tx_buf = ®
169 spi_message_add_tail(&t[1], &m);
170 }
171
172 spi_message_add_tail(&t[2], &m);
173 return spi_sync(ctx->spi, &m);
174 }
175
regmap_encx24j600_sfr_write(void * context,u8 reg,u8 * val,size_t len)176 static int regmap_encx24j600_sfr_write(void *context, u8 reg, u8 *val,
177 size_t len)
178 {
179 struct encx24j600_context *ctx = context;
180
181 return regmap_encx24j600_sfr_update(ctx, reg, val, len, WCRU, WCRCODE);
182 }
183
regmap_encx24j600_sfr_set_bits(struct encx24j600_context * ctx,u8 reg,u8 val)184 static int regmap_encx24j600_sfr_set_bits(struct encx24j600_context *ctx,
185 u8 reg, u8 val)
186 {
187 return regmap_encx24j600_sfr_update(ctx, reg, &val, 1, BFSU, BFSCODE);
188 }
189
regmap_encx24j600_sfr_clr_bits(struct encx24j600_context * ctx,u8 reg,u8 val)190 static int regmap_encx24j600_sfr_clr_bits(struct encx24j600_context *ctx,
191 u8 reg, u8 val)
192 {
193 return regmap_encx24j600_sfr_update(ctx, reg, &val, 1, BFCU, BFCCODE);
194 }
195
regmap_encx24j600_reg_update_bits(void * context,unsigned int reg,unsigned int mask,unsigned int val)196 static int regmap_encx24j600_reg_update_bits(void *context, unsigned int reg,
197 unsigned int mask,
198 unsigned int val)
199 {
200 struct encx24j600_context *ctx = context;
201
202 int ret = 0;
203 unsigned int set_mask = mask & val;
204 unsigned int clr_mask = mask & ~val;
205
206 if ((reg >= 0x40 && reg < 0x6c) || reg >= 0x80)
207 return -EINVAL;
208
209 if (set_mask & 0xff)
210 ret = regmap_encx24j600_sfr_set_bits(ctx, reg, set_mask);
211
212 set_mask = (set_mask & 0xff00) >> 8;
213
214 if ((set_mask & 0xff) && (ret == 0))
215 ret = regmap_encx24j600_sfr_set_bits(ctx, reg + 1, set_mask);
216
217 if ((clr_mask & 0xff) && (ret == 0))
218 ret = regmap_encx24j600_sfr_clr_bits(ctx, reg, clr_mask);
219
220 clr_mask = (clr_mask & 0xff00) >> 8;
221
222 if ((clr_mask & 0xff) && (ret == 0))
223 ret = regmap_encx24j600_sfr_clr_bits(ctx, reg + 1, clr_mask);
224
225 return ret;
226 }
227
regmap_encx24j600_spi_write(void * context,u8 reg,const u8 * data,size_t count)228 int regmap_encx24j600_spi_write(void *context, u8 reg, const u8 *data,
229 size_t count)
230 {
231 struct encx24j600_context *ctx = context;
232
233 if (reg < 0xc0)
234 return encx24j600_cmdn(ctx, reg, data, count);
235
236 /* SPI 1-byte command. Ignore data */
237 return spi_write(ctx->spi, ®, 1);
238 }
239 EXPORT_SYMBOL_GPL(regmap_encx24j600_spi_write);
240
regmap_encx24j600_spi_read(void * context,u8 reg,u8 * data,size_t count)241 int regmap_encx24j600_spi_read(void *context, u8 reg, u8 *data, size_t count)
242 {
243 struct encx24j600_context *ctx = context;
244
245 if (reg == RBSEL && count > 1)
246 count = 1;
247
248 return spi_write_then_read(ctx->spi, ®, sizeof(reg), data, count);
249 }
250 EXPORT_SYMBOL_GPL(regmap_encx24j600_spi_read);
251
regmap_encx24j600_write(void * context,const void * data,size_t len)252 static int regmap_encx24j600_write(void *context, const void *data,
253 size_t len)
254 {
255 u8 *dout = (u8 *)data;
256 u8 reg = dout[0];
257 ++dout;
258 --len;
259
260 if (reg > 0xa0)
261 return regmap_encx24j600_spi_write(context, reg, dout, len);
262
263 if (len > 2)
264 return -EINVAL;
265
266 return regmap_encx24j600_sfr_write(context, reg, dout, len);
267 }
268
regmap_encx24j600_read(void * context,const void * reg_buf,size_t reg_size,void * val,size_t val_size)269 static int regmap_encx24j600_read(void *context,
270 const void *reg_buf, size_t reg_size,
271 void *val, size_t val_size)
272 {
273 u8 reg = *(const u8 *)reg_buf;
274
275 if (reg_size != 1) {
276 pr_err("%s: reg=%02x reg_size=%zu\n", __func__, reg, reg_size);
277 return -EINVAL;
278 }
279
280 if (reg > 0xa0)
281 return regmap_encx24j600_spi_read(context, reg, val, val_size);
282
283 if (val_size > 2) {
284 pr_err("%s: reg=%02x val_size=%zu\n", __func__, reg, val_size);
285 return -EINVAL;
286 }
287
288 return regmap_encx24j600_sfr_read(context, reg, val, val_size);
289 }
290
encx24j600_regmap_readable(struct device * dev,unsigned int reg)291 static bool encx24j600_regmap_readable(struct device *dev, unsigned int reg)
292 {
293 if ((reg < 0x36) ||
294 ((reg >= 0x40) && (reg < 0x4c)) ||
295 ((reg >= 0x52) && (reg < 0x56)) ||
296 ((reg >= 0x60) && (reg < 0x66)) ||
297 ((reg >= 0x68) && (reg < 0x80)) ||
298 ((reg >= 0x86) && (reg < 0x92)) ||
299 (reg == 0xc8))
300 return true;
301 else
302 return false;
303 }
304
encx24j600_regmap_writeable(struct device * dev,unsigned int reg)305 static bool encx24j600_regmap_writeable(struct device *dev, unsigned int reg)
306 {
307 if ((reg < 0x12) ||
308 ((reg >= 0x14) && (reg < 0x1a)) ||
309 ((reg >= 0x1c) && (reg < 0x36)) ||
310 ((reg >= 0x40) && (reg < 0x4c)) ||
311 ((reg >= 0x52) && (reg < 0x56)) ||
312 ((reg >= 0x60) && (reg < 0x68)) ||
313 ((reg >= 0x6c) && (reg < 0x80)) ||
314 ((reg >= 0x86) && (reg < 0x92)) ||
315 ((reg >= 0xc0) && (reg < 0xc8)) ||
316 ((reg >= 0xca) && (reg < 0xf0)))
317 return true;
318 else
319 return false;
320 }
321
encx24j600_regmap_volatile(struct device * dev,unsigned int reg)322 static bool encx24j600_regmap_volatile(struct device *dev, unsigned int reg)
323 {
324 switch (reg) {
325 case ERXHEAD:
326 case EDMACS:
327 case ETXSTAT:
328 case ETXWIRE:
329 case ECON1: /* Can be modified via single byte cmds */
330 case ECON2: /* Can be modified via single byte cmds */
331 case ESTAT:
332 case EIR: /* Can be modified via single byte cmds */
333 case MIRD:
334 case MISTAT:
335 return true;
336 default:
337 break;
338 }
339
340 return false;
341 }
342
encx24j600_regmap_precious(struct device * dev,unsigned int reg)343 static bool encx24j600_regmap_precious(struct device *dev, unsigned int reg)
344 {
345 /* single byte cmds are precious */
346 if (((reg >= 0xc0) && (reg < 0xc8)) ||
347 ((reg >= 0xca) && (reg < 0xf0)))
348 return true;
349 else
350 return false;
351 }
352
regmap_encx24j600_phy_reg_read(void * context,unsigned int reg,unsigned int * val)353 static int regmap_encx24j600_phy_reg_read(void *context, unsigned int reg,
354 unsigned int *val)
355 {
356 struct encx24j600_context *ctx = context;
357 int ret;
358 unsigned int mistat;
359
360 reg = MIREGADR_VAL | (reg & PHREG_MASK);
361 ret = regmap_write(ctx->regmap, MIREGADR, reg);
362 if (unlikely(ret))
363 goto err_out;
364
365 ret = regmap_write(ctx->regmap, MICMD, MIIRD);
366 if (unlikely(ret))
367 goto err_out;
368
369 usleep_range(26, 100);
370 while ((ret = regmap_read(ctx->regmap, MISTAT, &mistat) != 0) &&
371 (mistat & BUSY))
372 cpu_relax();
373
374 if (unlikely(ret))
375 goto err_out;
376
377 ret = regmap_write(ctx->regmap, MICMD, 0);
378 if (unlikely(ret))
379 goto err_out;
380
381 ret = regmap_read(ctx->regmap, MIRD, val);
382
383 err_out:
384 if (ret)
385 pr_err("%s: error %d reading reg %02x\n", __func__, ret,
386 reg & PHREG_MASK);
387
388 return ret;
389 }
390
regmap_encx24j600_phy_reg_write(void * context,unsigned int reg,unsigned int val)391 static int regmap_encx24j600_phy_reg_write(void *context, unsigned int reg,
392 unsigned int val)
393 {
394 struct encx24j600_context *ctx = context;
395 int ret;
396 unsigned int mistat;
397
398 reg = MIREGADR_VAL | (reg & PHREG_MASK);
399 ret = regmap_write(ctx->regmap, MIREGADR, reg);
400 if (unlikely(ret))
401 goto err_out;
402
403 ret = regmap_write(ctx->regmap, MIWR, val);
404 if (unlikely(ret))
405 goto err_out;
406
407 usleep_range(26, 100);
408 while ((ret = regmap_read(ctx->regmap, MISTAT, &mistat) != 0) &&
409 (mistat & BUSY))
410 cpu_relax();
411
412 err_out:
413 if (ret)
414 pr_err("%s: error %d writing reg %02x=%04x\n", __func__, ret,
415 reg & PHREG_MASK, val);
416
417 return ret;
418 }
419
encx24j600_phymap_readable(struct device * dev,unsigned int reg)420 static bool encx24j600_phymap_readable(struct device *dev, unsigned int reg)
421 {
422 switch (reg) {
423 case PHCON1:
424 case PHSTAT1:
425 case PHANA:
426 case PHANLPA:
427 case PHANE:
428 case PHCON2:
429 case PHSTAT2:
430 case PHSTAT3:
431 return true;
432 default:
433 return false;
434 }
435 }
436
encx24j600_phymap_writeable(struct device * dev,unsigned int reg)437 static bool encx24j600_phymap_writeable(struct device *dev, unsigned int reg)
438 {
439 switch (reg) {
440 case PHCON1:
441 case PHCON2:
442 case PHANA:
443 return true;
444 case PHSTAT1:
445 case PHSTAT2:
446 case PHSTAT3:
447 case PHANLPA:
448 case PHANE:
449 default:
450 return false;
451 }
452 }
453
encx24j600_phymap_volatile(struct device * dev,unsigned int reg)454 static bool encx24j600_phymap_volatile(struct device *dev, unsigned int reg)
455 {
456 switch (reg) {
457 case PHSTAT1:
458 case PHSTAT2:
459 case PHSTAT3:
460 case PHANLPA:
461 case PHANE:
462 case PHCON2:
463 return true;
464 default:
465 return false;
466 }
467 }
468
469 static struct regmap_config regcfg = {
470 .name = "reg",
471 .reg_bits = 8,
472 .val_bits = 16,
473 .max_register = 0xee,
474 .reg_stride = 2,
475 .cache_type = REGCACHE_RBTREE,
476 .val_format_endian = REGMAP_ENDIAN_LITTLE,
477 .readable_reg = encx24j600_regmap_readable,
478 .writeable_reg = encx24j600_regmap_writeable,
479 .volatile_reg = encx24j600_regmap_volatile,
480 .precious_reg = encx24j600_regmap_precious,
481 .lock = regmap_lock_mutex,
482 .unlock = regmap_unlock_mutex,
483 };
484
485 static struct regmap_bus regmap_encx24j600 = {
486 .write = regmap_encx24j600_write,
487 .read = regmap_encx24j600_read,
488 .reg_update_bits = regmap_encx24j600_reg_update_bits,
489 };
490
491 static struct regmap_config phycfg = {
492 .name = "phy",
493 .reg_bits = 8,
494 .val_bits = 16,
495 .max_register = 0x1f,
496 .cache_type = REGCACHE_RBTREE,
497 .val_format_endian = REGMAP_ENDIAN_LITTLE,
498 .readable_reg = encx24j600_phymap_readable,
499 .writeable_reg = encx24j600_phymap_writeable,
500 .volatile_reg = encx24j600_phymap_volatile,
501 };
502
503 static struct regmap_bus phymap_encx24j600 = {
504 .reg_write = regmap_encx24j600_phy_reg_write,
505 .reg_read = regmap_encx24j600_phy_reg_read,
506 };
507
devm_regmap_init_encx24j600(struct device * dev,struct encx24j600_context * ctx)508 void devm_regmap_init_encx24j600(struct device *dev,
509 struct encx24j600_context *ctx)
510 {
511 mutex_init(&ctx->mutex);
512 regcfg.lock_arg = ctx;
513 ctx->regmap = devm_regmap_init(dev, ®map_encx24j600, ctx, ®cfg);
514 ctx->phymap = devm_regmap_init(dev, &phymap_encx24j600, ctx, &phycfg);
515 }
516 EXPORT_SYMBOL_GPL(devm_regmap_init_encx24j600);
517
518 MODULE_LICENSE("GPL");
519