Commit | Line | Data |
---|---|---|
6b99076c | 1 | // SPDX-License-Identifier: GPL-2.0-only |
680ca6dc CB |
2 | /* |
3 | * SCOM FSI Client device driver | |
4 | * | |
5 | * Copyright (C) IBM Corporation 2016 | |
680ca6dc CB |
6 | */ |
7 | ||
8 | #include <linux/fsi.h> | |
9 | #include <linux/module.h> | |
10 | #include <linux/cdev.h> | |
11 | #include <linux/delay.h> | |
12 | #include <linux/fs.h> | |
13 | #include <linux/uaccess.h> | |
14 | #include <linux/slab.h> | |
680ca6dc | 15 | #include <linux/list.h> |
680ca6dc | 16 | |
6b293258 BH |
17 | #include <uapi/linux/fsi.h> |
18 | ||
680ca6dc CB |
19 | #define FSI_ENGID_SCOM 0x5 |
20 | ||
680ca6dc CB |
21 | /* SCOM engine register set */ |
22 | #define SCOM_DATA0_REG 0x00 | |
23 | #define SCOM_DATA1_REG 0x04 | |
24 | #define SCOM_CMD_REG 0x08 | |
f1433044 BH |
25 | #define SCOM_FSI2PIB_RESET_REG 0x18 |
26 | #define SCOM_STATUS_REG 0x1C /* Read */ | |
27 | #define SCOM_PIB_RESET_REG 0x1C /* Write */ | |
680ca6dc | 28 | |
f1433044 | 29 | /* Command register */ |
680ca6dc | 30 | #define SCOM_WRITE_CMD 0x80000000 |
f1433044 BH |
31 | #define SCOM_READ_CMD 0x00000000 |
32 | ||
33 | /* Status register bits */ | |
34 | #define SCOM_STATUS_ERR_SUMMARY 0x80000000 | |
35 | #define SCOM_STATUS_PROTECTION 0x01000000 | |
6b293258 | 36 | #define SCOM_STATUS_PARITY 0x04000000 |
f1433044 BH |
37 | #define SCOM_STATUS_PIB_ABORT 0x00100000 |
38 | #define SCOM_STATUS_PIB_RESP_MASK 0x00007000 | |
39 | #define SCOM_STATUS_PIB_RESP_SHIFT 12 | |
40 | ||
8919dfcb | 41 | #define SCOM_STATUS_ANY_ERR (SCOM_STATUS_PROTECTION | \ |
6b293258 | 42 | SCOM_STATUS_PARITY | \ |
f1433044 BH |
43 | SCOM_STATUS_PIB_ABORT | \ |
44 | SCOM_STATUS_PIB_RESP_MASK) | |
6b293258 BH |
45 | /* SCOM address encodings */ |
46 | #define XSCOM_ADDR_IND_FLAG BIT_ULL(63) | |
47 | #define XSCOM_ADDR_INF_FORM1 BIT_ULL(60) | |
48 | ||
49 | /* SCOM indirect stuff */ | |
50 | #define XSCOM_ADDR_DIRECT_PART 0x7fffffffull | |
51 | #define XSCOM_ADDR_INDIRECT_PART 0x000fffff00000000ull | |
52 | #define XSCOM_DATA_IND_READ BIT_ULL(63) | |
53 | #define XSCOM_DATA_IND_COMPLETE BIT_ULL(31) | |
54 | #define XSCOM_DATA_IND_ERR_MASK 0x70000000ull | |
55 | #define XSCOM_DATA_IND_ERR_SHIFT 28 | |
56 | #define XSCOM_DATA_IND_DATA 0x0000ffffull | |
57 | #define XSCOM_DATA_IND_FORM1_DATA 0x000fffffffffffffull | |
58 | #define XSCOM_ADDR_FORM1_LOW 0x000ffffffffull | |
59 | #define XSCOM_ADDR_FORM1_HI 0xfff00000000ull | |
60 | #define XSCOM_ADDR_FORM1_HI_SHIFT 20 | |
61 | ||
62 | /* Retries */ | |
63 | #define SCOM_MAX_RETRIES 100 /* Retries on busy */ | |
64 | #define SCOM_MAX_IND_RETRIES 10 /* Retries indirect not ready */ | |
680ca6dc CB |
65 | |
66 | struct scom_device { | |
67 | struct list_head link; | |
68 | struct fsi_device *fsi_dev; | |
d8f45876 BH |
69 | struct device dev; |
70 | struct cdev cdev; | |
162c3946 | 71 | struct mutex lock; |
d8f45876 | 72 | bool dead; |
680ca6dc CB |
73 | }; |
74 | ||
6b293258 BH |
75 | static int __put_scom(struct scom_device *scom_dev, uint64_t value, |
76 | uint32_t addr, uint32_t *status) | |
680ca6dc | 77 | { |
6b293258 | 78 | __be32 data, raw_status; |
680ca6dc | 79 | int rc; |
680ca6dc | 80 | |
680ca6dc CB |
81 | data = cpu_to_be32((value >> 32) & 0xffffffff); |
82 | rc = fsi_device_write(scom_dev->fsi_dev, SCOM_DATA0_REG, &data, | |
83 | sizeof(uint32_t)); | |
84 | if (rc) | |
6b293258 | 85 | return rc; |
680ca6dc CB |
86 | |
87 | data = cpu_to_be32(value & 0xffffffff); | |
88 | rc = fsi_device_write(scom_dev->fsi_dev, SCOM_DATA1_REG, &data, | |
89 | sizeof(uint32_t)); | |
90 | if (rc) | |
6b293258 | 91 | return rc; |
680ca6dc CB |
92 | |
93 | data = cpu_to_be32(SCOM_WRITE_CMD | addr); | |
162c3946 | 94 | rc = fsi_device_write(scom_dev->fsi_dev, SCOM_CMD_REG, &data, |
680ca6dc | 95 | sizeof(uint32_t)); |
6b293258 BH |
96 | if (rc) |
97 | return rc; | |
98 | rc = fsi_device_read(scom_dev->fsi_dev, SCOM_STATUS_REG, &raw_status, | |
99 | sizeof(uint32_t)); | |
100 | if (rc) | |
101 | return rc; | |
102 | *status = be32_to_cpu(raw_status); | |
103 | ||
104 | return 0; | |
680ca6dc CB |
105 | } |
106 | ||
6b293258 BH |
107 | static int __get_scom(struct scom_device *scom_dev, uint64_t *value, |
108 | uint32_t addr, uint32_t *status) | |
680ca6dc | 109 | { |
6b293258 | 110 | __be32 data, raw_status; |
680ca6dc CB |
111 | int rc; |
112 | ||
162c3946 | 113 | |
680ca6dc | 114 | *value = 0ULL; |
f1433044 | 115 | data = cpu_to_be32(SCOM_READ_CMD | addr); |
680ca6dc CB |
116 | rc = fsi_device_write(scom_dev->fsi_dev, SCOM_CMD_REG, &data, |
117 | sizeof(uint32_t)); | |
118 | if (rc) | |
6b293258 BH |
119 | return rc; |
120 | rc = fsi_device_read(scom_dev->fsi_dev, SCOM_STATUS_REG, &raw_status, | |
121 | sizeof(uint32_t)); | |
122 | if (rc) | |
123 | return rc; | |
680ca6dc | 124 | |
6b293258 BH |
125 | /* |
126 | * Read the data registers even on error, so we don't have | |
127 | * to interpret the status register here. | |
128 | */ | |
129 | rc = fsi_device_read(scom_dev->fsi_dev, SCOM_DATA0_REG, &data, | |
680ca6dc CB |
130 | sizeof(uint32_t)); |
131 | if (rc) | |
6b293258 BH |
132 | return rc; |
133 | *value |= (uint64_t)be32_to_cpu(data) << 32; | |
134 | rc = fsi_device_read(scom_dev->fsi_dev, SCOM_DATA1_REG, &data, | |
680ca6dc CB |
135 | sizeof(uint32_t)); |
136 | if (rc) | |
6b293258 BH |
137 | return rc; |
138 | *value |= be32_to_cpu(data); | |
139 | *status = be32_to_cpu(raw_status); | |
140 | ||
141 | return rc; | |
142 | } | |
143 | ||
144 | static int put_indirect_scom_form0(struct scom_device *scom, uint64_t value, | |
145 | uint64_t addr, uint32_t *status) | |
146 | { | |
147 | uint64_t ind_data, ind_addr; | |
148 | int rc, retries, err = 0; | |
149 | ||
150 | if (value & ~XSCOM_DATA_IND_DATA) | |
151 | return -EINVAL; | |
152 | ||
153 | ind_addr = addr & XSCOM_ADDR_DIRECT_PART; | |
154 | ind_data = (addr & XSCOM_ADDR_INDIRECT_PART) | value; | |
155 | rc = __put_scom(scom, ind_data, ind_addr, status); | |
156 | if (rc || (*status & SCOM_STATUS_ANY_ERR)) | |
157 | return rc; | |
158 | ||
159 | for (retries = 0; retries < SCOM_MAX_IND_RETRIES; retries++) { | |
160 | rc = __get_scom(scom, &ind_data, addr, status); | |
161 | if (rc || (*status & SCOM_STATUS_ANY_ERR)) | |
162 | return rc; | |
163 | ||
164 | err = (ind_data & XSCOM_DATA_IND_ERR_MASK) >> XSCOM_DATA_IND_ERR_SHIFT; | |
165 | *status = err << SCOM_STATUS_PIB_RESP_SHIFT; | |
166 | if ((ind_data & XSCOM_DATA_IND_COMPLETE) || (err != SCOM_PIB_BLOCKED)) | |
167 | return 0; | |
168 | ||
169 | msleep(1); | |
170 | } | |
171 | return rc; | |
172 | } | |
173 | ||
174 | static int put_indirect_scom_form1(struct scom_device *scom, uint64_t value, | |
175 | uint64_t addr, uint32_t *status) | |
176 | { | |
177 | uint64_t ind_data, ind_addr; | |
178 | ||
179 | if (value & ~XSCOM_DATA_IND_FORM1_DATA) | |
180 | return -EINVAL; | |
181 | ||
182 | ind_addr = addr & XSCOM_ADDR_FORM1_LOW; | |
183 | ind_data = value | (addr & XSCOM_ADDR_FORM1_HI) << XSCOM_ADDR_FORM1_HI_SHIFT; | |
184 | return __put_scom(scom, ind_data, ind_addr, status); | |
185 | } | |
186 | ||
187 | static int get_indirect_scom_form0(struct scom_device *scom, uint64_t *value, | |
188 | uint64_t addr, uint32_t *status) | |
189 | { | |
190 | uint64_t ind_data, ind_addr; | |
191 | int rc, retries, err = 0; | |
192 | ||
193 | ind_addr = addr & XSCOM_ADDR_DIRECT_PART; | |
194 | ind_data = (addr & XSCOM_ADDR_INDIRECT_PART) | XSCOM_DATA_IND_READ; | |
195 | rc = __put_scom(scom, ind_data, ind_addr, status); | |
196 | if (rc || (*status & SCOM_STATUS_ANY_ERR)) | |
197 | return rc; | |
198 | ||
199 | for (retries = 0; retries < SCOM_MAX_IND_RETRIES; retries++) { | |
200 | rc = __get_scom(scom, &ind_data, addr, status); | |
201 | if (rc || (*status & SCOM_STATUS_ANY_ERR)) | |
202 | return rc; | |
203 | ||
204 | err = (ind_data & XSCOM_DATA_IND_ERR_MASK) >> XSCOM_DATA_IND_ERR_SHIFT; | |
205 | *status = err << SCOM_STATUS_PIB_RESP_SHIFT; | |
206 | *value = ind_data & XSCOM_DATA_IND_DATA; | |
207 | ||
208 | if ((ind_data & XSCOM_DATA_IND_COMPLETE) || (err != SCOM_PIB_BLOCKED)) | |
209 | return 0; | |
210 | ||
211 | msleep(1); | |
212 | } | |
213 | return rc; | |
214 | } | |
215 | ||
216 | static int raw_put_scom(struct scom_device *scom, uint64_t value, | |
217 | uint64_t addr, uint32_t *status) | |
218 | { | |
219 | if (addr & XSCOM_ADDR_IND_FLAG) { | |
220 | if (addr & XSCOM_ADDR_INF_FORM1) | |
221 | return put_indirect_scom_form1(scom, value, addr, status); | |
222 | else | |
223 | return put_indirect_scom_form0(scom, value, addr, status); | |
224 | } else | |
225 | return __put_scom(scom, value, addr, status); | |
226 | } | |
227 | ||
228 | static int raw_get_scom(struct scom_device *scom, uint64_t *value, | |
229 | uint64_t addr, uint32_t *status) | |
230 | { | |
231 | if (addr & XSCOM_ADDR_IND_FLAG) { | |
232 | if (addr & XSCOM_ADDR_INF_FORM1) | |
233 | return -ENXIO; | |
234 | return get_indirect_scom_form0(scom, value, addr, status); | |
235 | } else | |
236 | return __get_scom(scom, value, addr, status); | |
237 | } | |
238 | ||
239 | static int handle_fsi2pib_status(struct scom_device *scom, uint32_t status) | |
240 | { | |
241 | uint32_t dummy = -1; | |
242 | ||
243 | if (status & SCOM_STATUS_PROTECTION) | |
244 | return -EPERM; | |
245 | if (status & SCOM_STATUS_PARITY) { | |
246 | fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, &dummy, | |
247 | sizeof(uint32_t)); | |
248 | return -EIO; | |
249 | } | |
250 | /* Return -EBUSY on PIB abort to force a retry */ | |
251 | if (status & SCOM_STATUS_PIB_ABORT) | |
252 | return -EBUSY; | |
6b293258 BH |
253 | return 0; |
254 | } | |
255 | ||
256 | static int handle_pib_status(struct scom_device *scom, uint8_t status) | |
257 | { | |
258 | uint32_t dummy = -1; | |
259 | ||
260 | if (status == SCOM_PIB_SUCCESS) | |
261 | return 0; | |
262 | if (status == SCOM_PIB_BLOCKED) | |
263 | return -EBUSY; | |
264 | ||
265 | /* Reset the bridge */ | |
266 | fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, &dummy, | |
267 | sizeof(uint32_t)); | |
268 | ||
269 | switch(status) { | |
270 | case SCOM_PIB_OFFLINE: | |
271 | return -ENODEV; | |
272 | case SCOM_PIB_BAD_ADDR: | |
273 | return -ENXIO; | |
274 | case SCOM_PIB_TIMEOUT: | |
275 | return -ETIMEDOUT; | |
276 | case SCOM_PIB_PARTIAL: | |
277 | case SCOM_PIB_CLK_ERR: | |
278 | case SCOM_PIB_PARITY_ERR: | |
279 | default: | |
280 | return -EIO; | |
281 | } | |
282 | } | |
283 | ||
284 | static int put_scom(struct scom_device *scom, uint64_t value, | |
285 | uint64_t addr) | |
286 | { | |
287 | uint32_t status, dummy = -1; | |
288 | int rc, retries; | |
289 | ||
290 | for (retries = 0; retries < SCOM_MAX_RETRIES; retries++) { | |
291 | rc = raw_put_scom(scom, value, addr, &status); | |
292 | if (rc) { | |
293 | /* Try resetting the bridge if FSI fails */ | |
294 | if (rc != -ENODEV && retries == 0) { | |
295 | fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, | |
296 | &dummy, sizeof(uint32_t)); | |
297 | rc = -EBUSY; | |
298 | } else | |
299 | return rc; | |
300 | } else | |
301 | rc = handle_fsi2pib_status(scom, status); | |
302 | if (rc && rc != -EBUSY) | |
303 | break; | |
304 | if (rc == 0) { | |
305 | rc = handle_pib_status(scom, | |
306 | (status & SCOM_STATUS_PIB_RESP_MASK) | |
307 | >> SCOM_STATUS_PIB_RESP_SHIFT); | |
308 | if (rc && rc != -EBUSY) | |
309 | break; | |
310 | } | |
311 | if (rc == 0) | |
312 | break; | |
313 | msleep(1); | |
314 | } | |
315 | return rc; | |
316 | } | |
680ca6dc | 317 | |
6b293258 BH |
318 | static int get_scom(struct scom_device *scom, uint64_t *value, |
319 | uint64_t addr) | |
320 | { | |
321 | uint32_t status, dummy = -1; | |
322 | int rc, retries; | |
323 | ||
324 | for (retries = 0; retries < SCOM_MAX_RETRIES; retries++) { | |
325 | rc = raw_get_scom(scom, value, addr, &status); | |
326 | if (rc) { | |
327 | /* Try resetting the bridge if FSI fails */ | |
328 | if (rc != -ENODEV && retries == 0) { | |
329 | fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, | |
330 | &dummy, sizeof(uint32_t)); | |
331 | rc = -EBUSY; | |
332 | } else | |
333 | return rc; | |
334 | } else | |
335 | rc = handle_fsi2pib_status(scom, status); | |
336 | if (rc && rc != -EBUSY) | |
337 | break; | |
338 | if (rc == 0) { | |
339 | rc = handle_pib_status(scom, | |
340 | (status & SCOM_STATUS_PIB_RESP_MASK) | |
341 | >> SCOM_STATUS_PIB_RESP_SHIFT); | |
342 | if (rc && rc != -EBUSY) | |
343 | break; | |
344 | } | |
345 | if (rc == 0) | |
346 | break; | |
347 | msleep(1); | |
348 | } | |
162c3946 | 349 | return rc; |
680ca6dc CB |
350 | } |
351 | ||
352 | static ssize_t scom_read(struct file *filep, char __user *buf, size_t len, | |
bd213364 | 353 | loff_t *offset) |
680ca6dc | 354 | { |
d8f45876 | 355 | struct scom_device *scom = filep->private_data; |
680ca6dc CB |
356 | struct device *dev = &scom->fsi_dev->dev; |
357 | uint64_t val; | |
6b293258 | 358 | int rc; |
680ca6dc CB |
359 | |
360 | if (len != sizeof(uint64_t)) | |
361 | return -EINVAL; | |
362 | ||
6b293258 | 363 | mutex_lock(&scom->lock); |
d8f45876 BH |
364 | if (scom->dead) |
365 | rc = -ENODEV; | |
366 | else | |
367 | rc = get_scom(scom, &val, *offset); | |
6b293258 | 368 | mutex_unlock(&scom->lock); |
680ca6dc CB |
369 | if (rc) { |
370 | dev_dbg(dev, "get_scom fail:%d\n", rc); | |
371 | return rc; | |
372 | } | |
373 | ||
374 | rc = copy_to_user(buf, &val, len); | |
375 | if (rc) | |
376 | dev_dbg(dev, "copy to user failed:%d\n", rc); | |
377 | ||
378 | return rc ? rc : len; | |
379 | } | |
380 | ||
381 | static ssize_t scom_write(struct file *filep, const char __user *buf, | |
bd213364 | 382 | size_t len, loff_t *offset) |
680ca6dc CB |
383 | { |
384 | int rc; | |
d8f45876 | 385 | struct scom_device *scom = filep->private_data; |
680ca6dc CB |
386 | struct device *dev = &scom->fsi_dev->dev; |
387 | uint64_t val; | |
388 | ||
389 | if (len != sizeof(uint64_t)) | |
390 | return -EINVAL; | |
391 | ||
392 | rc = copy_from_user(&val, buf, len); | |
393 | if (rc) { | |
394 | dev_dbg(dev, "copy from user failed:%d\n", rc); | |
395 | return -EINVAL; | |
396 | } | |
397 | ||
6b293258 | 398 | mutex_lock(&scom->lock); |
d8f45876 BH |
399 | if (scom->dead) |
400 | rc = -ENODEV; | |
401 | else | |
402 | rc = put_scom(scom, val, *offset); | |
6b293258 | 403 | mutex_unlock(&scom->lock); |
680ca6dc CB |
404 | if (rc) { |
405 | dev_dbg(dev, "put_scom failed with:%d\n", rc); | |
406 | return rc; | |
407 | } | |
408 | ||
409 | return len; | |
410 | } | |
411 | ||
412 | static loff_t scom_llseek(struct file *file, loff_t offset, int whence) | |
413 | { | |
414 | switch (whence) { | |
415 | case SEEK_CUR: | |
416 | break; | |
417 | case SEEK_SET: | |
418 | file->f_pos = offset; | |
419 | break; | |
420 | default: | |
421 | return -EINVAL; | |
422 | } | |
423 | ||
424 | return offset; | |
425 | } | |
426 | ||
6b293258 BH |
427 | static void raw_convert_status(struct scom_access *acc, uint32_t status) |
428 | { | |
429 | acc->pib_status = (status & SCOM_STATUS_PIB_RESP_MASK) >> | |
430 | SCOM_STATUS_PIB_RESP_SHIFT; | |
431 | acc->intf_errors = 0; | |
432 | ||
433 | if (status & SCOM_STATUS_PROTECTION) | |
434 | acc->intf_errors |= SCOM_INTF_ERR_PROTECTION; | |
435 | else if (status & SCOM_STATUS_PARITY) | |
436 | acc->intf_errors |= SCOM_INTF_ERR_PARITY; | |
437 | else if (status & SCOM_STATUS_PIB_ABORT) | |
438 | acc->intf_errors |= SCOM_INTF_ERR_ABORT; | |
439 | else if (status & SCOM_STATUS_ERR_SUMMARY) | |
440 | acc->intf_errors |= SCOM_INTF_ERR_UNKNOWN; | |
441 | } | |
442 | ||
443 | static int scom_raw_read(struct scom_device *scom, void __user *argp) | |
444 | { | |
445 | struct scom_access acc; | |
446 | uint32_t status; | |
447 | int rc; | |
448 | ||
449 | if (copy_from_user(&acc, argp, sizeof(struct scom_access))) | |
450 | return -EFAULT; | |
451 | ||
452 | rc = raw_get_scom(scom, &acc.data, acc.addr, &status); | |
453 | if (rc) | |
454 | return rc; | |
455 | raw_convert_status(&acc, status); | |
456 | if (copy_to_user(argp, &acc, sizeof(struct scom_access))) | |
457 | return -EFAULT; | |
458 | return 0; | |
459 | } | |
460 | ||
461 | static int scom_raw_write(struct scom_device *scom, void __user *argp) | |
462 | { | |
463 | u64 prev_data, mask, data; | |
464 | struct scom_access acc; | |
465 | uint32_t status; | |
466 | int rc; | |
467 | ||
468 | if (copy_from_user(&acc, argp, sizeof(struct scom_access))) | |
469 | return -EFAULT; | |
470 | ||
471 | if (acc.mask) { | |
472 | rc = raw_get_scom(scom, &prev_data, acc.addr, &status); | |
473 | if (rc) | |
474 | return rc; | |
475 | if (status & SCOM_STATUS_ANY_ERR) | |
476 | goto fail; | |
477 | mask = acc.mask; | |
478 | } else { | |
479 | prev_data = mask = -1ull; | |
480 | } | |
481 | data = (prev_data & ~mask) | (acc.data & mask); | |
482 | rc = raw_put_scom(scom, data, acc.addr, &status); | |
483 | if (rc) | |
484 | return rc; | |
485 | fail: | |
486 | raw_convert_status(&acc, status); | |
487 | if (copy_to_user(argp, &acc, sizeof(struct scom_access))) | |
488 | return -EFAULT; | |
489 | return 0; | |
490 | } | |
491 | ||
492 | static int scom_reset(struct scom_device *scom, void __user *argp) | |
493 | { | |
494 | uint32_t flags, dummy = -1; | |
495 | int rc = 0; | |
496 | ||
497 | if (get_user(flags, (__u32 __user *)argp)) | |
498 | return -EFAULT; | |
499 | if (flags & SCOM_RESET_PIB) | |
500 | rc = fsi_device_write(scom->fsi_dev, SCOM_PIB_RESET_REG, &dummy, | |
501 | sizeof(uint32_t)); | |
502 | if (!rc && (flags & (SCOM_RESET_PIB | SCOM_RESET_INTF))) | |
503 | rc = fsi_device_write(scom->fsi_dev, SCOM_FSI2PIB_RESET_REG, &dummy, | |
504 | sizeof(uint32_t)); | |
505 | return rc; | |
506 | } | |
507 | ||
508 | static int scom_check(struct scom_device *scom, void __user *argp) | |
509 | { | |
510 | /* Still need to find out how to get "protected" */ | |
511 | return put_user(SCOM_CHECK_SUPPORTED, (__u32 __user *)argp); | |
512 | } | |
513 | ||
514 | static long scom_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
515 | { | |
d8f45876 | 516 | struct scom_device *scom = file->private_data; |
6b293258 BH |
517 | void __user *argp = (void __user *)arg; |
518 | int rc = -ENOTTY; | |
519 | ||
520 | mutex_lock(&scom->lock); | |
d8f45876 BH |
521 | if (scom->dead) { |
522 | mutex_unlock(&scom->lock); | |
523 | return -ENODEV; | |
524 | } | |
6b293258 BH |
525 | switch(cmd) { |
526 | case FSI_SCOM_CHECK: | |
527 | rc = scom_check(scom, argp); | |
528 | break; | |
529 | case FSI_SCOM_READ: | |
530 | rc = scom_raw_read(scom, argp); | |
531 | break; | |
532 | case FSI_SCOM_WRITE: | |
533 | rc = scom_raw_write(scom, argp); | |
534 | break; | |
535 | case FSI_SCOM_RESET: | |
536 | rc = scom_reset(scom, argp); | |
537 | break; | |
538 | } | |
539 | mutex_unlock(&scom->lock); | |
540 | return rc; | |
541 | } | |
542 | ||
d8f45876 BH |
543 | static int scom_open(struct inode *inode, struct file *file) |
544 | { | |
545 | struct scom_device *scom = container_of(inode->i_cdev, struct scom_device, cdev); | |
546 | ||
547 | file->private_data = scom; | |
548 | ||
549 | return 0; | |
550 | } | |
551 | ||
680ca6dc | 552 | static const struct file_operations scom_fops = { |
6b293258 | 553 | .owner = THIS_MODULE, |
d8f45876 | 554 | .open = scom_open, |
6b293258 BH |
555 | .llseek = scom_llseek, |
556 | .read = scom_read, | |
557 | .write = scom_write, | |
558 | .unlocked_ioctl = scom_ioctl, | |
680ca6dc CB |
559 | }; |
560 | ||
d8f45876 BH |
561 | static void scom_free(struct device *dev) |
562 | { | |
563 | struct scom_device *scom = container_of(dev, struct scom_device, dev); | |
564 | ||
565 | put_device(&scom->fsi_dev->dev); | |
566 | kfree(scom); | |
567 | } | |
568 | ||
680ca6dc CB |
569 | static int scom_probe(struct device *dev) |
570 | { | |
571 | struct fsi_device *fsi_dev = to_fsi_dev(dev); | |
572 | struct scom_device *scom; | |
d8f45876 | 573 | int rc, didx; |
680ca6dc | 574 | |
d8f45876 | 575 | scom = kzalloc(sizeof(*scom), GFP_KERNEL); |
680ca6dc CB |
576 | if (!scom) |
577 | return -ENOMEM; | |
d8f45876 | 578 | dev_set_drvdata(dev, scom); |
162c3946 | 579 | mutex_init(&scom->lock); |
d8f45876 BH |
580 | |
581 | /* Grab a reference to the device (parent of our cdev), we'll drop it later */ | |
582 | if (!get_device(dev)) { | |
583 | kfree(scom); | |
584 | return -ENODEV; | |
585 | } | |
aa1221b2 | 586 | scom->fsi_dev = fsi_dev; |
d8f45876 BH |
587 | |
588 | /* Create chardev for userspace access */ | |
589 | scom->dev.type = &fsi_cdev_type; | |
590 | scom->dev.parent = dev; | |
591 | scom->dev.release = scom_free; | |
592 | device_initialize(&scom->dev); | |
593 | ||
594 | /* Allocate a minor in the FSI space */ | |
595 | rc = fsi_get_new_minor(fsi_dev, fsi_dev_scom, &scom->dev.devt, &didx); | |
596 | if (rc) | |
597 | goto err; | |
598 | ||
599 | dev_set_name(&scom->dev, "scom%d", didx); | |
600 | cdev_init(&scom->cdev, &scom_fops); | |
601 | rc = cdev_device_add(&scom->cdev, &scom->dev); | |
602 | if (rc) { | |
603 | dev_err(dev, "Error %d creating char device %s\n", | |
604 | rc, dev_name(&scom->dev)); | |
605 | goto err_free_minor; | |
606 | } | |
607 | ||
608 | return 0; | |
609 | err_free_minor: | |
610 | fsi_free_minor(scom->dev.devt); | |
611 | err: | |
612 | put_device(&scom->dev); | |
613 | return rc; | |
680ca6dc CB |
614 | } |
615 | ||
616 | static int scom_remove(struct device *dev) | |
617 | { | |
d8f45876 | 618 | struct scom_device *scom = dev_get_drvdata(dev); |
680ca6dc | 619 | |
d8f45876 BH |
620 | mutex_lock(&scom->lock); |
621 | scom->dead = true; | |
622 | mutex_unlock(&scom->lock); | |
623 | cdev_device_del(&scom->cdev, &scom->dev); | |
624 | fsi_free_minor(scom->dev.devt); | |
625 | put_device(&scom->dev); | |
680ca6dc CB |
626 | |
627 | return 0; | |
628 | } | |
629 | ||
630 | static struct fsi_device_id scom_ids[] = { | |
631 | { | |
632 | .engine_type = FSI_ENGID_SCOM, | |
633 | .version = FSI_VERSION_ANY, | |
634 | }, | |
635 | { 0 } | |
636 | }; | |
637 | ||
638 | static struct fsi_driver scom_drv = { | |
639 | .id_table = scom_ids, | |
640 | .drv = { | |
641 | .name = "scom", | |
642 | .bus = &fsi_bus_type, | |
643 | .probe = scom_probe, | |
644 | .remove = scom_remove, | |
645 | } | |
646 | }; | |
647 | ||
648 | static int scom_init(void) | |
649 | { | |
680ca6dc CB |
650 | return fsi_driver_register(&scom_drv); |
651 | } | |
652 | ||
653 | static void scom_exit(void) | |
654 | { | |
680ca6dc CB |
655 | fsi_driver_unregister(&scom_drv); |
656 | } | |
657 | ||
658 | module_init(scom_init); | |
659 | module_exit(scom_exit); | |
660 | MODULE_LICENSE("GPL"); |