Merge tag 'misc-habanalabs-next-2020-09-25' of git://people.freedesktop.org/~gabbayo...
[linux-2.6-block.git] / drivers / slimbus / core.c
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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2011-2017, The Linux Foundation
4 */
5
6#include <linux/kernel.h>
7#include <linux/errno.h>
8#include <linux/slab.h>
9#include <linux/init.h>
46a2bb5a 10#include <linux/idr.h>
7588a511 11#include <linux/of.h>
9e663f48 12#include <linux/of_device.h>
4b14e62a 13#include <linux/pm_runtime.h>
3648e78e 14#include <linux/slimbus.h>
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15#include "slimbus.h"
16
17static DEFINE_IDA(ctrl_ida);
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18
19static const struct slim_device_id *slim_match(const struct slim_device_id *id,
20 const struct slim_device *sbdev)
21{
22 while (id->manf_id != 0 || id->prod_code != 0) {
23 if (id->manf_id == sbdev->e_addr.manf_id &&
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24 id->prod_code == sbdev->e_addr.prod_code &&
25 id->dev_index == sbdev->e_addr.dev_index &&
26 id->instance == sbdev->e_addr.instance)
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27 return id;
28 id++;
29 }
30 return NULL;
31}
32
33static int slim_device_match(struct device *dev, struct device_driver *drv)
34{
35 struct slim_device *sbdev = to_slim_device(dev);
36 struct slim_driver *sbdrv = to_slim_driver(drv);
37
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38 /* Attempt an OF style match first */
39 if (of_driver_match_device(dev, drv))
40 return 1;
41
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42 return !!slim_match(sbdrv->id_table, sbdev);
43}
44
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45static void slim_device_update_status(struct slim_device *sbdev,
46 enum slim_device_status status)
47{
48 struct slim_driver *sbdrv;
49
50 if (sbdev->status == status)
51 return;
52
53 sbdev->status = status;
54 if (!sbdev->dev.driver)
55 return;
56
57 sbdrv = to_slim_driver(sbdev->dev.driver);
58 if (sbdrv->device_status)
59 sbdrv->device_status(sbdev, sbdev->status);
60}
61
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62static int slim_device_probe(struct device *dev)
63{
64 struct slim_device *sbdev = to_slim_device(dev);
65 struct slim_driver *sbdrv = to_slim_driver(dev->driver);
8f3d5fcd 66 int ret;
3648e78e 67
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68 ret = sbdrv->probe(sbdev);
69 if (ret)
70 return ret;
71
72 /* try getting the logical address after probe */
73 ret = slim_get_logical_addr(sbdev);
74 if (!ret) {
380c6246 75 slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_UP);
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76 } else {
77 dev_err(&sbdev->dev, "Failed to get logical address\n");
78 ret = -EPROBE_DEFER;
79 }
80
81 return ret;
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82}
83
84static int slim_device_remove(struct device *dev)
85{
86 struct slim_device *sbdev = to_slim_device(dev);
87 struct slim_driver *sbdrv;
88
89 if (dev->driver) {
90 sbdrv = to_slim_driver(dev->driver);
91 if (sbdrv->remove)
92 sbdrv->remove(sbdev);
93 }
94
95 return 0;
96}
97
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98static int slim_device_uevent(struct device *dev, struct kobj_uevent_env *env)
99{
100 struct slim_device *sbdev = to_slim_device(dev);
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101
102 return add_uevent_var(env, "MODALIAS=slim:%s", dev_name(&sbdev->dev));
103}
104
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105struct bus_type slimbus_bus = {
106 .name = "slimbus",
107 .match = slim_device_match,
108 .probe = slim_device_probe,
109 .remove = slim_device_remove,
9e663f48 110 .uevent = slim_device_uevent,
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111};
112EXPORT_SYMBOL_GPL(slimbus_bus);
113
114/*
115 * __slim_driver_register() - Client driver registration with SLIMbus
116 *
117 * @drv:Client driver to be associated with client-device.
118 * @owner: owning module/driver
119 *
120 * This API will register the client driver with the SLIMbus
121 * It is called from the driver's module-init function.
122 */
123int __slim_driver_register(struct slim_driver *drv, struct module *owner)
124{
125 /* ID table and probe are mandatory */
14a649d3 126 if (!(drv->driver.of_match_table || drv->id_table) || !drv->probe)
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127 return -EINVAL;
128
129 drv->driver.bus = &slimbus_bus;
130 drv->driver.owner = owner;
131
132 return driver_register(&drv->driver);
133}
134EXPORT_SYMBOL_GPL(__slim_driver_register);
135
136/*
137 * slim_driver_unregister() - Undo effect of slim_driver_register
138 *
139 * @drv: Client driver to be unregistered
140 */
141void slim_driver_unregister(struct slim_driver *drv)
142{
143 driver_unregister(&drv->driver);
144}
145EXPORT_SYMBOL_GPL(slim_driver_unregister);
146
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147static void slim_dev_release(struct device *dev)
148{
149 struct slim_device *sbdev = to_slim_device(dev);
150
151 kfree(sbdev);
152}
153
154static int slim_add_device(struct slim_controller *ctrl,
155 struct slim_device *sbdev,
156 struct device_node *node)
157{
158 sbdev->dev.bus = &slimbus_bus;
159 sbdev->dev.parent = ctrl->dev;
160 sbdev->dev.release = slim_dev_release;
161 sbdev->dev.driver = NULL;
162 sbdev->ctrl = ctrl;
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163 INIT_LIST_HEAD(&sbdev->stream_list);
164 spin_lock_init(&sbdev->stream_list_lock);
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165 sbdev->dev.of_node = of_node_get(node);
166 sbdev->dev.fwnode = of_fwnode_handle(node);
7588a511 167
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168 dev_set_name(&sbdev->dev, "%x:%x:%x:%x",
169 sbdev->e_addr.manf_id,
170 sbdev->e_addr.prod_code,
171 sbdev->e_addr.dev_index,
172 sbdev->e_addr.instance);
173
174 return device_register(&sbdev->dev);
175}
176
177static struct slim_device *slim_alloc_device(struct slim_controller *ctrl,
178 struct slim_eaddr *eaddr,
179 struct device_node *node)
180{
181 struct slim_device *sbdev;
182 int ret;
183
184 sbdev = kzalloc(sizeof(*sbdev), GFP_KERNEL);
185 if (!sbdev)
186 return NULL;
187
188 sbdev->e_addr = *eaddr;
189 ret = slim_add_device(ctrl, sbdev, node);
190 if (ret) {
bd329f02 191 put_device(&sbdev->dev);
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192 return NULL;
193 }
194
195 return sbdev;
196}
197
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198static void of_register_slim_devices(struct slim_controller *ctrl)
199{
200 struct device *dev = ctrl->dev;
201 struct device_node *node;
202
203 if (!ctrl->dev->of_node)
204 return;
205
206 for_each_child_of_node(ctrl->dev->of_node, node) {
207 struct slim_device *sbdev;
208 struct slim_eaddr e_addr;
209 const char *compat = NULL;
210 int reg[2], ret;
211 int manf_id, prod_code;
212
213 compat = of_get_property(node, "compatible", NULL);
214 if (!compat)
215 continue;
216
217 ret = sscanf(compat, "slim%x,%x", &manf_id, &prod_code);
218 if (ret != 2) {
219 dev_err(dev, "Manf ID & Product code not found %s\n",
220 compat);
221 continue;
222 }
223
224 ret = of_property_read_u32_array(node, "reg", reg, 2);
225 if (ret) {
226 dev_err(dev, "Device and Instance id not found:%d\n",
227 ret);
228 continue;
229 }
230
231 e_addr.dev_index = reg[0];
232 e_addr.instance = reg[1];
233 e_addr.manf_id = manf_id;
234 e_addr.prod_code = prod_code;
235
236 sbdev = slim_alloc_device(ctrl, &e_addr, node);
237 if (!sbdev)
238 continue;
239 }
240}
241
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242/*
243 * slim_register_controller() - Controller bring-up and registration.
244 *
245 * @ctrl: Controller to be registered.
246 *
247 * A controller is registered with the framework using this API.
248 * If devices on a controller were registered before controller,
249 * this will make sure that they get probed when controller is up
250 */
251int slim_register_controller(struct slim_controller *ctrl)
252{
253 int id;
254
255 id = ida_simple_get(&ctrl_ida, 0, 0, GFP_KERNEL);
256 if (id < 0)
257 return id;
258
259 ctrl->id = id;
260
261 if (!ctrl->min_cg)
262 ctrl->min_cg = SLIM_MIN_CLK_GEAR;
263 if (!ctrl->max_cg)
264 ctrl->max_cg = SLIM_MAX_CLK_GEAR;
265
266 ida_init(&ctrl->laddr_ida);
267 idr_init(&ctrl->tid_idr);
268 mutex_init(&ctrl->lock);
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269 mutex_init(&ctrl->sched.m_reconf);
270 init_completion(&ctrl->sched.pause_comp);
8147760d 271 spin_lock_init(&ctrl->txn_lock);
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272
273 dev_dbg(ctrl->dev, "Bus [%s] registered:dev:%p\n",
274 ctrl->name, ctrl->dev);
275
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276 of_register_slim_devices(ctrl);
277
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278 return 0;
279}
280EXPORT_SYMBOL_GPL(slim_register_controller);
281
282/* slim_remove_device: Remove the effect of slim_add_device() */
283static void slim_remove_device(struct slim_device *sbdev)
284{
01360857 285 of_node_put(sbdev->dev.of_node);
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286 device_unregister(&sbdev->dev);
287}
288
289static int slim_ctrl_remove_device(struct device *dev, void *null)
290{
291 slim_remove_device(to_slim_device(dev));
292 return 0;
293}
294
295/**
296 * slim_unregister_controller() - Controller tear-down.
297 *
298 * @ctrl: Controller to tear-down.
299 */
300int slim_unregister_controller(struct slim_controller *ctrl)
301{
302 /* Remove all clients */
303 device_for_each_child(ctrl->dev, NULL, slim_ctrl_remove_device);
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304 /* Enter Clock Pause */
305 slim_ctrl_clk_pause(ctrl, false, 0);
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306 ida_simple_remove(&ctrl_ida, ctrl->id);
307
308 return 0;
309}
310EXPORT_SYMBOL_GPL(slim_unregister_controller);
311
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312/**
313 * slim_report_absent() - Controller calls this function when a device
314 * reports absent, OR when the device cannot be communicated with
315 *
316 * @sbdev: Device that cannot be reached, or sent report absent
317 */
318void slim_report_absent(struct slim_device *sbdev)
319{
320 struct slim_controller *ctrl = sbdev->ctrl;
321
322 if (!ctrl)
323 return;
324
325 /* invalidate logical addresses */
326 mutex_lock(&ctrl->lock);
327 sbdev->is_laddr_valid = false;
328 mutex_unlock(&ctrl->lock);
329
330 ida_simple_remove(&ctrl->laddr_ida, sbdev->laddr);
331 slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_DOWN);
332}
333EXPORT_SYMBOL_GPL(slim_report_absent);
334
335static bool slim_eaddr_equal(struct slim_eaddr *a, struct slim_eaddr *b)
336{
337 return (a->manf_id == b->manf_id &&
338 a->prod_code == b->prod_code &&
339 a->dev_index == b->dev_index &&
340 a->instance == b->instance);
341}
342
343static int slim_match_dev(struct device *dev, void *data)
344{
345 struct slim_eaddr *e_addr = data;
346 struct slim_device *sbdev = to_slim_device(dev);
347
348 return slim_eaddr_equal(&sbdev->e_addr, e_addr);
349}
350
351static struct slim_device *find_slim_device(struct slim_controller *ctrl,
352 struct slim_eaddr *eaddr)
353{
354 struct slim_device *sbdev;
355 struct device *dev;
356
357 dev = device_find_child(ctrl->dev, eaddr, slim_match_dev);
358 if (dev) {
359 sbdev = to_slim_device(dev);
360 return sbdev;
361 }
362
363 return NULL;
364}
365
366/**
367 * slim_get_device() - get handle to a device.
368 *
369 * @ctrl: Controller on which this device will be added/queried
370 * @e_addr: Enumeration address of the device to be queried
371 *
372 * Return: pointer to a device if it has already reported. Creates a new
373 * device and returns pointer to it if the device has not yet enumerated.
374 */
375struct slim_device *slim_get_device(struct slim_controller *ctrl,
376 struct slim_eaddr *e_addr)
377{
378 struct slim_device *sbdev;
379
380 sbdev = find_slim_device(ctrl, e_addr);
381 if (!sbdev) {
382 sbdev = slim_alloc_device(ctrl, e_addr, NULL);
383 if (!sbdev)
384 return ERR_PTR(-ENOMEM);
385 }
386
387 return sbdev;
388}
389EXPORT_SYMBOL_GPL(slim_get_device);
390
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391static int of_slim_match_dev(struct device *dev, void *data)
392{
393 struct device_node *np = data;
394 struct slim_device *sbdev = to_slim_device(dev);
395
396 return (sbdev->dev.of_node == np);
397}
398
399static struct slim_device *of_find_slim_device(struct slim_controller *ctrl,
400 struct device_node *np)
401{
402 struct slim_device *sbdev;
403 struct device *dev;
404
405 dev = device_find_child(ctrl->dev, np, of_slim_match_dev);
406 if (dev) {
407 sbdev = to_slim_device(dev);
408 return sbdev;
409 }
410
411 return NULL;
412}
413
414/**
415 * of_slim_get_device() - get handle to a device using dt node.
416 *
417 * @ctrl: Controller on which this device will be added/queried
418 * @np: node pointer to device
419 *
420 * Return: pointer to a device if it has already reported. Creates a new
421 * device and returns pointer to it if the device has not yet enumerated.
422 */
423struct slim_device *of_slim_get_device(struct slim_controller *ctrl,
424 struct device_node *np)
425{
426 return of_find_slim_device(ctrl, np);
427}
428EXPORT_SYMBOL_GPL(of_slim_get_device);
429
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430static int slim_device_alloc_laddr(struct slim_device *sbdev,
431 bool report_present)
432{
433 struct slim_controller *ctrl = sbdev->ctrl;
434 u8 laddr;
435 int ret;
436
437 mutex_lock(&ctrl->lock);
438 if (ctrl->get_laddr) {
439 ret = ctrl->get_laddr(ctrl, &sbdev->e_addr, &laddr);
440 if (ret < 0)
441 goto err;
442 } else if (report_present) {
443 ret = ida_simple_get(&ctrl->laddr_ida,
444 0, SLIM_LA_MANAGER - 1, GFP_KERNEL);
445 if (ret < 0)
446 goto err;
447
448 laddr = ret;
449 } else {
450 ret = -EINVAL;
451 goto err;
452 }
453
454 if (ctrl->set_laddr) {
455 ret = ctrl->set_laddr(ctrl, &sbdev->e_addr, laddr);
456 if (ret) {
457 ret = -EINVAL;
458 goto err;
459 }
460 }
461
462 sbdev->laddr = laddr;
463 sbdev->is_laddr_valid = true;
cfb32101 464 mutex_unlock(&ctrl->lock);
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465
466 slim_device_update_status(sbdev, SLIM_DEVICE_STATUS_UP);
467
468 dev_dbg(ctrl->dev, "setting slimbus l-addr:%x, ea:%x,%x,%x,%x\n",
469 laddr, sbdev->e_addr.manf_id, sbdev->e_addr.prod_code,
470 sbdev->e_addr.dev_index, sbdev->e_addr.instance);
471
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472 return 0;
473
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474err:
475 mutex_unlock(&ctrl->lock);
476 return ret;
477
478}
479
480/**
481 * slim_device_report_present() - Report enumerated device.
482 *
483 * @ctrl: Controller with which device is enumerated.
484 * @e_addr: Enumeration address of the device.
485 * @laddr: Return logical address (if valid flag is false)
486 *
487 * Called by controller in response to REPORT_PRESENT. Framework will assign
488 * a logical address to this enumeration address.
489 * Function returns -EXFULL to indicate that all logical addresses are already
490 * taken.
491 */
492int slim_device_report_present(struct slim_controller *ctrl,
493 struct slim_eaddr *e_addr, u8 *laddr)
494{
495 struct slim_device *sbdev;
496 int ret;
497
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498 ret = pm_runtime_get_sync(ctrl->dev);
499
500 if (ctrl->sched.clk_state != SLIM_CLK_ACTIVE) {
501 dev_err(ctrl->dev, "slim ctrl not active,state:%d, ret:%d\n",
502 ctrl->sched.clk_state, ret);
503 goto slimbus_not_active;
504 }
505
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506 sbdev = slim_get_device(ctrl, e_addr);
507 if (IS_ERR(sbdev))
508 return -ENODEV;
509
510 if (sbdev->is_laddr_valid) {
511 *laddr = sbdev->laddr;
512 return 0;
513 }
514
515 ret = slim_device_alloc_laddr(sbdev, true);
516
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517slimbus_not_active:
518 pm_runtime_mark_last_busy(ctrl->dev);
519 pm_runtime_put_autosuspend(ctrl->dev);
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520 return ret;
521}
522EXPORT_SYMBOL_GPL(slim_device_report_present);
523
524/**
525 * slim_get_logical_addr() - get/allocate logical address of a SLIMbus device.
526 *
527 * @sbdev: client handle requesting the address.
528 *
529 * Return: zero if a logical address is valid or a new logical address
530 * has been assigned. error code in case of error.
531 */
532int slim_get_logical_addr(struct slim_device *sbdev)
533{
534 if (!sbdev->is_laddr_valid)
535 return slim_device_alloc_laddr(sbdev, false);
536
537 return 0;
538}
539EXPORT_SYMBOL_GPL(slim_get_logical_addr);
540
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541static void __exit slimbus_exit(void)
542{
543 bus_unregister(&slimbus_bus);
544}
545module_exit(slimbus_exit);
546
547static int __init slimbus_init(void)
548{
549 return bus_register(&slimbus_bus);
550}
551postcore_initcall(slimbus_init);
552
553MODULE_LICENSE("GPL v2");
554MODULE_DESCRIPTION("SLIMbus core");