1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2016 Robert Jarzmik <robert.jarzmik@free.fr> |
4 | */ |
5 | |
6 | #include <linux/module.h> |
7 | #include <linux/bitops.h> |
8 | #include <linux/clk.h> |
9 | #include <linux/device.h> |
10 | #include <linux/idr.h> |
11 | #include <linux/list.h> |
12 | #include <linux/mutex.h> |
13 | #include <linux/of.h> |
14 | #include <linux/pm.h> |
15 | #include <linux/pm_runtime.h> |
16 | #include <linux/slab.h> |
17 | #include <linux/sysfs.h> |
18 | #include <sound/ac97_codec.h> |
19 | #include <sound/ac97/codec.h> |
20 | #include <sound/ac97/controller.h> |
21 | #include <sound/ac97/regs.h> |
22 | |
23 | #include "ac97_core.h" |
24 | |
25 | /* |
26 | * Protects ac97_controllers and each ac97_controller structure. |
27 | */ |
28 | static DEFINE_MUTEX(ac97_controllers_mutex); |
29 | static DEFINE_IDR(ac97_adapter_idr); |
30 | static LIST_HEAD(ac97_controllers); |
31 | |
32 | static inline struct ac97_controller* |
33 | to_ac97_controller(struct device *ac97_adapter) |
34 | { |
35 | return container_of(ac97_adapter, struct ac97_controller, adap); |
36 | } |
37 | |
38 | static int ac97_unbound_ctrl_write(struct ac97_controller *adrv, int slot, |
39 | unsigned short reg, unsigned short val) |
40 | { |
41 | return -ENODEV; |
42 | } |
43 | |
44 | static int ac97_unbound_ctrl_read(struct ac97_controller *adrv, int slot, |
45 | unsigned short reg) |
46 | { |
47 | return -ENODEV; |
48 | } |
49 | |
50 | static const struct ac97_controller_ops ac97_unbound_ctrl_ops = { |
51 | .write = ac97_unbound_ctrl_write, |
52 | .read = ac97_unbound_ctrl_read, |
53 | }; |
54 | |
55 | static struct ac97_controller ac97_unbound_ctrl = { |
56 | .ops = &ac97_unbound_ctrl_ops, |
57 | }; |
58 | |
59 | static struct ac97_codec_device * |
60 | ac97_codec_find(struct ac97_controller *ac97_ctrl, unsigned int codec_num) |
61 | { |
62 | if (codec_num >= AC97_BUS_MAX_CODECS) |
63 | return ERR_PTR(error: -EINVAL); |
64 | |
65 | return ac97_ctrl->codecs[codec_num]; |
66 | } |
67 | |
68 | static struct device_node * |
69 | ac97_of_get_child_device(struct ac97_controller *ac97_ctrl, int idx, |
70 | unsigned int vendor_id) |
71 | { |
72 | struct device_node *node; |
73 | u32 reg; |
74 | char compat[] = "ac97,0000,0000" ; |
75 | |
76 | snprintf(buf: compat, size: sizeof(compat), fmt: "ac97,%04x,%04x" , |
77 | vendor_id >> 16, vendor_id & 0xffff); |
78 | |
79 | for_each_child_of_node(ac97_ctrl->parent->of_node, node) { |
80 | if ((idx != of_property_read_u32(np: node, propname: "reg" , out_value: ®)) || |
81 | !of_device_is_compatible(device: node, compat)) |
82 | continue; |
83 | return node; |
84 | } |
85 | |
86 | return NULL; |
87 | } |
88 | |
89 | static void ac97_codec_release(struct device *dev) |
90 | { |
91 | struct ac97_codec_device *adev; |
92 | struct ac97_controller *ac97_ctrl; |
93 | |
94 | adev = to_ac97_device(d: dev); |
95 | ac97_ctrl = adev->ac97_ctrl; |
96 | ac97_ctrl->codecs[adev->num] = NULL; |
97 | of_node_put(node: dev->of_node); |
98 | kfree(objp: adev); |
99 | } |
100 | |
101 | static int ac97_codec_add(struct ac97_controller *ac97_ctrl, int idx, |
102 | unsigned int vendor_id) |
103 | { |
104 | struct ac97_codec_device *codec; |
105 | int ret; |
106 | |
107 | codec = kzalloc(size: sizeof(*codec), GFP_KERNEL); |
108 | if (!codec) |
109 | return -ENOMEM; |
110 | ac97_ctrl->codecs[idx] = codec; |
111 | codec->vendor_id = vendor_id; |
112 | codec->dev.release = ac97_codec_release; |
113 | codec->dev.bus = &ac97_bus_type; |
114 | codec->dev.parent = &ac97_ctrl->adap; |
115 | codec->num = idx; |
116 | codec->ac97_ctrl = ac97_ctrl; |
117 | |
118 | device_initialize(dev: &codec->dev); |
119 | dev_set_name(dev: &codec->dev, name: "%s:%u" , dev_name(dev: ac97_ctrl->parent), idx); |
120 | codec->dev.of_node = ac97_of_get_child_device(ac97_ctrl, idx, |
121 | vendor_id); |
122 | |
123 | ret = device_add(dev: &codec->dev); |
124 | if (ret) { |
125 | put_device(dev: &codec->dev); |
126 | return ret; |
127 | } |
128 | |
129 | return 0; |
130 | } |
131 | |
132 | unsigned int snd_ac97_bus_scan_one(struct ac97_controller *adrv, |
133 | unsigned int codec_num) |
134 | { |
135 | unsigned short vid1, vid2; |
136 | int ret; |
137 | |
138 | ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID1); |
139 | vid1 = (ret & 0xffff); |
140 | if (ret < 0) |
141 | return 0; |
142 | |
143 | ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID2); |
144 | vid2 = (ret & 0xffff); |
145 | if (ret < 0) |
146 | return 0; |
147 | |
148 | dev_dbg(&adrv->adap, "%s(codec_num=%u): vendor_id=0x%08x\n" , |
149 | __func__, codec_num, AC97_ID(vid1, vid2)); |
150 | return AC97_ID(vid1, vid2); |
151 | } |
152 | |
153 | static int ac97_bus_scan(struct ac97_controller *ac97_ctrl) |
154 | { |
155 | int ret, i; |
156 | unsigned int vendor_id; |
157 | |
158 | for (i = 0; i < AC97_BUS_MAX_CODECS; i++) { |
159 | if (ac97_codec_find(ac97_ctrl, codec_num: i)) |
160 | continue; |
161 | if (!(ac97_ctrl->slots_available & BIT(i))) |
162 | continue; |
163 | vendor_id = snd_ac97_bus_scan_one(adrv: ac97_ctrl, codec_num: i); |
164 | if (!vendor_id) |
165 | continue; |
166 | |
167 | ret = ac97_codec_add(ac97_ctrl, idx: i, vendor_id); |
168 | if (ret < 0) |
169 | return ret; |
170 | } |
171 | return 0; |
172 | } |
173 | |
174 | static int ac97_bus_reset(struct ac97_controller *ac97_ctrl) |
175 | { |
176 | ac97_ctrl->ops->reset(ac97_ctrl); |
177 | |
178 | return 0; |
179 | } |
180 | |
181 | /** |
182 | * snd_ac97_codec_driver_register - register an AC97 codec driver |
183 | * @dev: AC97 driver codec to register |
184 | * |
185 | * Register an AC97 codec driver to the ac97 bus driver, aka. the AC97 digital |
186 | * controller. |
187 | * |
188 | * Returns 0 on success or error code |
189 | */ |
190 | int snd_ac97_codec_driver_register(struct ac97_codec_driver *drv) |
191 | { |
192 | drv->driver.bus = &ac97_bus_type; |
193 | return driver_register(drv: &drv->driver); |
194 | } |
195 | EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_register); |
196 | |
197 | /** |
198 | * snd_ac97_codec_driver_unregister - unregister an AC97 codec driver |
199 | * @dev: AC97 codec driver to unregister |
200 | * |
201 | * Unregister a previously registered ac97 codec driver. |
202 | */ |
203 | void snd_ac97_codec_driver_unregister(struct ac97_codec_driver *drv) |
204 | { |
205 | driver_unregister(drv: &drv->driver); |
206 | } |
207 | EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_unregister); |
208 | |
209 | /** |
210 | * snd_ac97_codec_get_platdata - get platform_data |
211 | * @adev: the ac97 codec device |
212 | * |
213 | * For legacy platforms, in order to have platform_data in codec drivers |
214 | * available, while ac97 device are auto-created upon probe, this retrieves the |
215 | * platdata which was setup on ac97 controller registration. |
216 | * |
217 | * Returns the platform data pointer |
218 | */ |
219 | void *snd_ac97_codec_get_platdata(const struct ac97_codec_device *adev) |
220 | { |
221 | struct ac97_controller *ac97_ctrl = adev->ac97_ctrl; |
222 | |
223 | return ac97_ctrl->codecs_pdata[adev->num]; |
224 | } |
225 | EXPORT_SYMBOL_GPL(snd_ac97_codec_get_platdata); |
226 | |
227 | static void ac97_ctrl_codecs_unregister(struct ac97_controller *ac97_ctrl) |
228 | { |
229 | int i; |
230 | |
231 | for (i = 0; i < AC97_BUS_MAX_CODECS; i++) |
232 | if (ac97_ctrl->codecs[i]) { |
233 | ac97_ctrl->codecs[i]->ac97_ctrl = &ac97_unbound_ctrl; |
234 | device_unregister(dev: &ac97_ctrl->codecs[i]->dev); |
235 | } |
236 | } |
237 | |
238 | static ssize_t cold_reset_store(struct device *dev, |
239 | struct device_attribute *attr, const char *buf, |
240 | size_t len) |
241 | { |
242 | struct ac97_controller *ac97_ctrl; |
243 | |
244 | mutex_lock(&ac97_controllers_mutex); |
245 | ac97_ctrl = to_ac97_controller(ac97_adapter: dev); |
246 | ac97_ctrl->ops->reset(ac97_ctrl); |
247 | mutex_unlock(lock: &ac97_controllers_mutex); |
248 | return len; |
249 | } |
250 | static DEVICE_ATTR_WO(cold_reset); |
251 | |
252 | static ssize_t warm_reset_store(struct device *dev, |
253 | struct device_attribute *attr, const char *buf, |
254 | size_t len) |
255 | { |
256 | struct ac97_controller *ac97_ctrl; |
257 | |
258 | if (!dev) |
259 | return -ENODEV; |
260 | |
261 | mutex_lock(&ac97_controllers_mutex); |
262 | ac97_ctrl = to_ac97_controller(ac97_adapter: dev); |
263 | ac97_ctrl->ops->warm_reset(ac97_ctrl); |
264 | mutex_unlock(lock: &ac97_controllers_mutex); |
265 | return len; |
266 | } |
267 | static DEVICE_ATTR_WO(warm_reset); |
268 | |
269 | static struct attribute *ac97_controller_device_attrs[] = { |
270 | &dev_attr_cold_reset.attr, |
271 | &dev_attr_warm_reset.attr, |
272 | NULL |
273 | }; |
274 | |
275 | static const struct attribute_group ac97_adapter_attr_group = { |
276 | .name = "ac97_operations" , |
277 | .attrs = ac97_controller_device_attrs, |
278 | }; |
279 | |
280 | static const struct attribute_group *ac97_adapter_groups[] = { |
281 | &ac97_adapter_attr_group, |
282 | NULL, |
283 | }; |
284 | |
285 | static void ac97_del_adapter(struct ac97_controller *ac97_ctrl) |
286 | { |
287 | mutex_lock(&ac97_controllers_mutex); |
288 | ac97_ctrl_codecs_unregister(ac97_ctrl); |
289 | list_del(entry: &ac97_ctrl->controllers); |
290 | mutex_unlock(lock: &ac97_controllers_mutex); |
291 | |
292 | device_unregister(dev: &ac97_ctrl->adap); |
293 | } |
294 | |
295 | static void ac97_adapter_release(struct device *dev) |
296 | { |
297 | struct ac97_controller *ac97_ctrl; |
298 | |
299 | ac97_ctrl = to_ac97_controller(ac97_adapter: dev); |
300 | idr_remove(&ac97_adapter_idr, id: ac97_ctrl->nr); |
301 | dev_dbg(&ac97_ctrl->adap, "adapter unregistered by %s\n" , |
302 | dev_name(ac97_ctrl->parent)); |
303 | } |
304 | |
305 | static const struct device_type ac97_adapter_type = { |
306 | .groups = ac97_adapter_groups, |
307 | .release = ac97_adapter_release, |
308 | }; |
309 | |
310 | static int ac97_add_adapter(struct ac97_controller *ac97_ctrl) |
311 | { |
312 | int ret; |
313 | |
314 | mutex_lock(&ac97_controllers_mutex); |
315 | ret = idr_alloc(&ac97_adapter_idr, ptr: ac97_ctrl, start: 0, end: 0, GFP_KERNEL); |
316 | ac97_ctrl->nr = ret; |
317 | if (ret >= 0) { |
318 | dev_set_name(dev: &ac97_ctrl->adap, name: "ac97-%d" , ret); |
319 | ac97_ctrl->adap.type = &ac97_adapter_type; |
320 | ac97_ctrl->adap.parent = ac97_ctrl->parent; |
321 | ret = device_register(dev: &ac97_ctrl->adap); |
322 | if (ret) |
323 | put_device(dev: &ac97_ctrl->adap); |
324 | } |
325 | if (!ret) |
326 | list_add(new: &ac97_ctrl->controllers, head: &ac97_controllers); |
327 | mutex_unlock(lock: &ac97_controllers_mutex); |
328 | |
329 | if (!ret) |
330 | dev_dbg(&ac97_ctrl->adap, "adapter registered by %s\n" , |
331 | dev_name(ac97_ctrl->parent)); |
332 | return ret; |
333 | } |
334 | |
335 | /** |
336 | * snd_ac97_controller_register - register an ac97 controller |
337 | * @ops: the ac97 bus operations |
338 | * @dev: the device providing the ac97 DC function |
339 | * @slots_available: mask of the ac97 codecs that can be scanned and probed |
340 | * bit0 => codec 0, bit1 => codec 1 ... bit 3 => codec 3 |
341 | * |
342 | * Register a digital controller which can control up to 4 ac97 codecs. This is |
343 | * the controller side of the AC97 AC-link, while the slave side are the codecs. |
344 | * |
345 | * Returns a valid controller upon success, negative pointer value upon error |
346 | */ |
347 | struct ac97_controller *snd_ac97_controller_register( |
348 | const struct ac97_controller_ops *ops, struct device *dev, |
349 | unsigned short slots_available, void **codecs_pdata) |
350 | { |
351 | struct ac97_controller *ac97_ctrl; |
352 | int ret, i; |
353 | |
354 | ac97_ctrl = kzalloc(size: sizeof(*ac97_ctrl), GFP_KERNEL); |
355 | if (!ac97_ctrl) |
356 | return ERR_PTR(error: -ENOMEM); |
357 | |
358 | for (i = 0; i < AC97_BUS_MAX_CODECS && codecs_pdata; i++) |
359 | ac97_ctrl->codecs_pdata[i] = codecs_pdata[i]; |
360 | |
361 | ac97_ctrl->ops = ops; |
362 | ac97_ctrl->slots_available = slots_available; |
363 | ac97_ctrl->parent = dev; |
364 | ret = ac97_add_adapter(ac97_ctrl); |
365 | |
366 | if (ret) |
367 | goto err; |
368 | ac97_bus_reset(ac97_ctrl); |
369 | ac97_bus_scan(ac97_ctrl); |
370 | |
371 | return ac97_ctrl; |
372 | err: |
373 | kfree(objp: ac97_ctrl); |
374 | return ERR_PTR(error: ret); |
375 | } |
376 | EXPORT_SYMBOL_GPL(snd_ac97_controller_register); |
377 | |
378 | /** |
379 | * snd_ac97_controller_unregister - unregister an ac97 controller |
380 | * @ac97_ctrl: the device previously provided to ac97_controller_register() |
381 | * |
382 | */ |
383 | void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl) |
384 | { |
385 | ac97_del_adapter(ac97_ctrl); |
386 | } |
387 | EXPORT_SYMBOL_GPL(snd_ac97_controller_unregister); |
388 | |
389 | #ifdef CONFIG_PM |
390 | static int ac97_pm_runtime_suspend(struct device *dev) |
391 | { |
392 | struct ac97_codec_device *codec = to_ac97_device(d: dev); |
393 | int ret = pm_generic_runtime_suspend(dev); |
394 | |
395 | if (ret == 0 && dev->driver) { |
396 | if (pm_runtime_is_irq_safe(dev)) |
397 | clk_disable(clk: codec->clk); |
398 | else |
399 | clk_disable_unprepare(clk: codec->clk); |
400 | } |
401 | |
402 | return ret; |
403 | } |
404 | |
405 | static int ac97_pm_runtime_resume(struct device *dev) |
406 | { |
407 | struct ac97_codec_device *codec = to_ac97_device(d: dev); |
408 | int ret; |
409 | |
410 | if (dev->driver) { |
411 | if (pm_runtime_is_irq_safe(dev)) |
412 | ret = clk_enable(clk: codec->clk); |
413 | else |
414 | ret = clk_prepare_enable(clk: codec->clk); |
415 | if (ret) |
416 | return ret; |
417 | } |
418 | |
419 | return pm_generic_runtime_resume(dev); |
420 | } |
421 | #endif /* CONFIG_PM */ |
422 | |
423 | static const struct dev_pm_ops ac97_pm = { |
424 | .suspend = pm_generic_suspend, |
425 | .resume = pm_generic_resume, |
426 | .freeze = pm_generic_freeze, |
427 | .thaw = pm_generic_thaw, |
428 | .poweroff = pm_generic_poweroff, |
429 | .restore = pm_generic_restore, |
430 | SET_RUNTIME_PM_OPS( |
431 | ac97_pm_runtime_suspend, |
432 | ac97_pm_runtime_resume, |
433 | NULL) |
434 | }; |
435 | |
436 | static int ac97_get_enable_clk(struct ac97_codec_device *adev) |
437 | { |
438 | int ret; |
439 | |
440 | adev->clk = clk_get(dev: &adev->dev, id: "ac97_clk" ); |
441 | if (IS_ERR(ptr: adev->clk)) |
442 | return PTR_ERR(ptr: adev->clk); |
443 | |
444 | ret = clk_prepare_enable(clk: adev->clk); |
445 | if (ret) |
446 | clk_put(clk: adev->clk); |
447 | |
448 | return ret; |
449 | } |
450 | |
451 | static void ac97_put_disable_clk(struct ac97_codec_device *adev) |
452 | { |
453 | clk_disable_unprepare(clk: adev->clk); |
454 | clk_put(clk: adev->clk); |
455 | } |
456 | |
457 | static ssize_t vendor_id_show(struct device *dev, |
458 | struct device_attribute *attr, char *buf) |
459 | { |
460 | struct ac97_codec_device *codec = to_ac97_device(d: dev); |
461 | |
462 | return sysfs_emit(buf, fmt: "%08x" , codec->vendor_id); |
463 | } |
464 | static DEVICE_ATTR_RO(vendor_id); |
465 | |
466 | static struct attribute *ac97_dev_attrs[] = { |
467 | &dev_attr_vendor_id.attr, |
468 | NULL, |
469 | }; |
470 | ATTRIBUTE_GROUPS(ac97_dev); |
471 | |
472 | static int ac97_bus_match(struct device *dev, struct device_driver *drv) |
473 | { |
474 | struct ac97_codec_device *adev = to_ac97_device(d: dev); |
475 | struct ac97_codec_driver *adrv = to_ac97_driver(d: drv); |
476 | const struct ac97_id *id = adrv->id_table; |
477 | int i = 0; |
478 | |
479 | if (adev->vendor_id == 0x0 || adev->vendor_id == 0xffffffff) |
480 | return false; |
481 | |
482 | do { |
483 | if (ac97_ids_match(id1: id[i].id, id2: adev->vendor_id, mask: id[i].mask)) |
484 | return true; |
485 | } while (id[i++].id); |
486 | |
487 | return false; |
488 | } |
489 | |
490 | static int ac97_bus_probe(struct device *dev) |
491 | { |
492 | struct ac97_codec_device *adev = to_ac97_device(d: dev); |
493 | struct ac97_codec_driver *adrv = to_ac97_driver(d: dev->driver); |
494 | int ret; |
495 | |
496 | ret = ac97_get_enable_clk(adev); |
497 | if (ret) |
498 | return ret; |
499 | |
500 | pm_runtime_get_noresume(dev); |
501 | pm_runtime_set_active(dev); |
502 | pm_runtime_enable(dev); |
503 | |
504 | ret = adrv->probe(adev); |
505 | if (ret == 0) |
506 | return 0; |
507 | |
508 | pm_runtime_disable(dev); |
509 | pm_runtime_set_suspended(dev); |
510 | pm_runtime_put_noidle(dev); |
511 | ac97_put_disable_clk(adev); |
512 | |
513 | return ret; |
514 | } |
515 | |
516 | static void ac97_bus_remove(struct device *dev) |
517 | { |
518 | struct ac97_codec_device *adev = to_ac97_device(d: dev); |
519 | struct ac97_codec_driver *adrv = to_ac97_driver(d: dev->driver); |
520 | int ret; |
521 | |
522 | ret = pm_runtime_resume_and_get(dev); |
523 | if (ret < 0) |
524 | return; |
525 | |
526 | adrv->remove(adev); |
527 | pm_runtime_put_noidle(dev); |
528 | ac97_put_disable_clk(adev); |
529 | |
530 | pm_runtime_disable(dev); |
531 | } |
532 | |
533 | const struct bus_type ac97_bus_type = { |
534 | .name = "ac97bus" , |
535 | .dev_groups = ac97_dev_groups, |
536 | .match = ac97_bus_match, |
537 | .pm = &ac97_pm, |
538 | .probe = ac97_bus_probe, |
539 | .remove = ac97_bus_remove, |
540 | }; |
541 | |
542 | static int __init ac97_bus_init(void) |
543 | { |
544 | return bus_register(bus: &ac97_bus_type); |
545 | } |
546 | subsys_initcall(ac97_bus_init); |
547 | |
548 | static void __exit ac97_bus_exit(void) |
549 | { |
550 | bus_unregister(bus: &ac97_bus_type); |
551 | } |
552 | module_exit(ac97_bus_exit); |
553 | |
554 | MODULE_LICENSE("GPL" ); |
555 | MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>" ); |
556 | |