1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * omap_device implementation
4 *
5 * Copyright (C) 2009-2010 Nokia Corporation
6 * Paul Walmsley, Kevin Hilman
7 *
8 * Developed in collaboration with (alphabetical order): Benoit
9 * Cousson, Thara Gopinath, Tony Lindgren, Rajendra Nayak, Vikram
10 * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
11 * Woodruff
12 *
13 * This code provides a consistent interface for OMAP device drivers
14 * to control power management and interconnect properties of their
15 * devices.
16 *
17 * In the medium- to long-term, this code should be implemented as a
18 * proper omap_bus/omap_device in Linux, no more platform_data func
19 * pointers
20 */
21#undef DEBUG
22
23#include <linux/kernel.h>
24#include <linux/platform_device.h>
25#include <linux/slab.h>
26#include <linux/err.h>
27#include <linux/io.h>
28#include <linux/clk.h>
29#include <linux/clkdev.h>
30#include <linux/pm_domain.h>
31#include <linux/pm_runtime.h>
32#include <linux/of.h>
33#include <linux/of_address.h>
34#include <linux/of_irq.h>
35#include <linux/notifier.h>
36
37#include "common.h"
38#include "soc.h"
39#include "omap_device.h"
40#include "omap_hwmod.h"
41
42static struct omap_device *omap_device_alloc(struct platform_device *pdev,
43 struct omap_hwmod **ohs, int oh_cnt);
44static void omap_device_delete(struct omap_device *od);
45static struct dev_pm_domain omap_device_fail_pm_domain;
46static struct dev_pm_domain omap_device_pm_domain;
47
48/* Private functions */
49
50static void _add_clkdev(struct omap_device *od, const char *clk_alias,
51 const char *clk_name)
52{
53 struct clk *r;
54 int rc;
55
56 if (!clk_alias || !clk_name)
57 return;
58
59 dev_dbg(&od->pdev->dev, "Creating %s -> %s\n", clk_alias, clk_name);
60
61 r = clk_get_sys(dev_id: dev_name(dev: &od->pdev->dev), con_id: clk_alias);
62 if (!IS_ERR(ptr: r)) {
63 dev_dbg(&od->pdev->dev,
64 "alias %s already exists\n", clk_alias);
65 clk_put(clk: r);
66 return;
67 }
68
69 r = clk_get_sys(NULL, con_id: clk_name);
70
71 if (IS_ERR(ptr: r)) {
72 struct of_phandle_args clkspec;
73
74 clkspec.np = of_find_node_by_name(NULL, name: clk_name);
75
76 r = of_clk_get_from_provider(clkspec: &clkspec);
77
78 rc = clk_register_clkdev(r, clk_alias,
79 dev_name(dev: &od->pdev->dev));
80 } else {
81 rc = clk_add_alias(clk_alias, dev_name(dev: &od->pdev->dev),
82 clk_name, NULL);
83 }
84
85 if (rc) {
86 if (rc == -ENODEV || rc == -ENOMEM)
87 dev_err(&od->pdev->dev,
88 "clkdev_alloc for %s failed\n", clk_alias);
89 else
90 dev_err(&od->pdev->dev,
91 "clk_get for %s failed\n", clk_name);
92 }
93}
94
95/**
96 * _add_hwmod_clocks_clkdev - Add clkdev entry for hwmod optional clocks
97 * and main clock
98 * @od: struct omap_device *od
99 * @oh: struct omap_hwmod *oh
100 *
101 * For the main clock and every optional clock present per hwmod per
102 * omap_device, this function adds an entry in the clkdev table of the
103 * form <dev-id=dev_name, con-id=role> if it does not exist already.
104 *
105 * This allows drivers to get a pointer to its optional clocks based on its role
106 * by calling clk_get(<dev*>, <role>).
107 * In the case of the main clock, a "fck" alias is used.
108 *
109 * No return value.
110 */
111static void _add_hwmod_clocks_clkdev(struct omap_device *od,
112 struct omap_hwmod *oh)
113{
114 int i;
115
116 _add_clkdev(od, clk_alias: "fck", clk_name: oh->main_clk);
117
118 for (i = 0; i < oh->opt_clks_cnt; i++)
119 _add_clkdev(od, clk_alias: oh->opt_clks[i].role, clk_name: oh->opt_clks[i].clk);
120}
121
122
123/**
124 * omap_device_build_from_dt - build an omap_device with multiple hwmods
125 * @pdev: The platform device to update.
126 *
127 * Function for building an omap_device already registered from device-tree
128 *
129 * Returns 0 or PTR_ERR() on error.
130 */
131static int omap_device_build_from_dt(struct platform_device *pdev)
132{
133 struct omap_hwmod **hwmods;
134 struct omap_device *od;
135 struct omap_hwmod *oh;
136 struct device_node *node = pdev->dev.of_node;
137 struct resource res;
138 const char *oh_name;
139 int oh_cnt, i, ret = 0;
140 bool device_active = false, skip_pm_domain = false;
141
142 oh_cnt = of_property_count_strings(np: node, propname: "ti,hwmods");
143 if (oh_cnt <= 0) {
144 dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
145 return -ENODEV;
146 }
147
148 /* SDMA still needs special handling for omap_device_build() */
149 ret = of_property_read_string_index(np: node, propname: "ti,hwmods", index: 0, output: &oh_name);
150 if (!ret && (!strncmp("dma_system", oh_name, 10) ||
151 !strncmp("dma", oh_name, 3)))
152 skip_pm_domain = true;
153
154 /* Use ti-sysc driver instead of omap_device? */
155 if (!skip_pm_domain &&
156 !omap_hwmod_parse_module_range(NULL, node, &res))
157 return -ENODEV;
158
159 hwmods = kcalloc(n: oh_cnt, size: sizeof(struct omap_hwmod *), GFP_KERNEL);
160 if (!hwmods) {
161 ret = -ENOMEM;
162 goto odbfd_exit;
163 }
164
165 for (i = 0; i < oh_cnt; i++) {
166 of_property_read_string_index(np: node, propname: "ti,hwmods", index: i, output: &oh_name);
167 oh = omap_hwmod_lookup(oh_name);
168 if (!oh) {
169 dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
170 oh_name);
171 ret = -EINVAL;
172 goto odbfd_exit1;
173 }
174 hwmods[i] = oh;
175 if (oh->flags & HWMOD_INIT_NO_IDLE)
176 device_active = true;
177 }
178
179 od = omap_device_alloc(pdev, ohs: hwmods, oh_cnt);
180 if (IS_ERR(ptr: od)) {
181 dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
182 oh_name);
183 ret = PTR_ERR(ptr: od);
184 goto odbfd_exit1;
185 }
186
187 /* Fix up missing resource names */
188 for (i = 0; i < pdev->num_resources; i++) {
189 struct resource *r = &pdev->resource[i];
190
191 if (r->name == NULL)
192 r->name = dev_name(dev: &pdev->dev);
193 }
194
195 if (!skip_pm_domain) {
196 dev_pm_domain_set(dev: &pdev->dev, pd: &omap_device_pm_domain);
197 if (device_active) {
198 omap_device_enable(pdev);
199 pm_runtime_set_active(dev: &pdev->dev);
200 }
201 }
202
203odbfd_exit1:
204 kfree(objp: hwmods);
205odbfd_exit:
206 /* if data/we are at fault.. load up a fail handler */
207 if (ret)
208 dev_pm_domain_set(dev: &pdev->dev, pd: &omap_device_fail_pm_domain);
209
210 return ret;
211}
212
213static int _omap_device_notifier_call(struct notifier_block *nb,
214 unsigned long event, void *dev)
215{
216 struct platform_device *pdev = to_platform_device(dev);
217 struct omap_device *od;
218 int err;
219
220 switch (event) {
221 case BUS_NOTIFY_REMOVED_DEVICE:
222 if (pdev->archdata.od)
223 omap_device_delete(od: pdev->archdata.od);
224 break;
225 case BUS_NOTIFY_UNBOUND_DRIVER:
226 od = to_omap_device(pdev);
227 if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) {
228 dev_info(dev, "enabled after unload, idling\n");
229 err = omap_device_idle(pdev);
230 if (err)
231 dev_err(dev, "failed to idle\n");
232 }
233 break;
234 case BUS_NOTIFY_BIND_DRIVER:
235 od = to_omap_device(pdev);
236 if (od) {
237 od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
238 if (od->_state == OMAP_DEVICE_STATE_ENABLED &&
239 pm_runtime_status_suspended(dev)) {
240 pm_runtime_set_active(dev);
241 }
242 }
243 break;
244 case BUS_NOTIFY_ADD_DEVICE:
245 if (pdev->dev.of_node)
246 omap_device_build_from_dt(pdev);
247 fallthrough;
248 default:
249 od = to_omap_device(pdev);
250 if (od)
251 od->_driver_status = event;
252 }
253
254 return NOTIFY_DONE;
255}
256
257/**
258 * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
259 * @od: struct omap_device *od
260 *
261 * Enable all underlying hwmods. Returns 0.
262 */
263static int _omap_device_enable_hwmods(struct omap_device *od)
264{
265 int ret = 0;
266 int i;
267
268 for (i = 0; i < od->hwmods_cnt; i++)
269 ret |= omap_hwmod_enable(od->hwmods[i]);
270
271 return ret;
272}
273
274/**
275 * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
276 * @od: struct omap_device *od
277 *
278 * Idle all underlying hwmods. Returns 0.
279 */
280static int _omap_device_idle_hwmods(struct omap_device *od)
281{
282 int ret = 0;
283 int i;
284
285 for (i = 0; i < od->hwmods_cnt; i++)
286 ret |= omap_hwmod_idle(od->hwmods[i]);
287
288 return ret;
289}
290
291/* Public functions for use by core code */
292
293/**
294 * omap_device_alloc - allocate an omap_device
295 * @pdev: platform_device that will be included in this omap_device
296 * @ohs: ptr to the omap_hwmod for this omap_device
297 * @oh_cnt: the size of the ohs list
298 *
299 * Convenience function for allocating an omap_device structure and filling
300 * hwmods, and resources.
301 *
302 * Returns an struct omap_device pointer or ERR_PTR() on error;
303 */
304static struct omap_device *omap_device_alloc(struct platform_device *pdev,
305 struct omap_hwmod **ohs, int oh_cnt)
306{
307 int ret = -ENOMEM;
308 struct omap_device *od;
309 int i;
310 struct omap_hwmod **hwmods;
311
312 od = kzalloc(size: sizeof(struct omap_device), GFP_KERNEL);
313 if (!od)
314 goto oda_exit1;
315
316 od->hwmods_cnt = oh_cnt;
317
318 hwmods = kmemdup(p: ohs, size: sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
319 if (!hwmods)
320 goto oda_exit2;
321
322 od->hwmods = hwmods;
323 od->pdev = pdev;
324 pdev->archdata.od = od;
325
326 for (i = 0; i < oh_cnt; i++) {
327 hwmods[i]->od = od;
328 _add_hwmod_clocks_clkdev(od, oh: hwmods[i]);
329 }
330
331 return od;
332
333oda_exit2:
334 kfree(objp: od);
335oda_exit1:
336 dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
337
338 return ERR_PTR(error: ret);
339}
340
341static void omap_device_delete(struct omap_device *od)
342{
343 if (!od)
344 return;
345
346 od->pdev->archdata.od = NULL;
347 kfree(objp: od->hwmods);
348 kfree(objp: od);
349}
350
351#ifdef CONFIG_PM
352static int _od_runtime_suspend(struct device *dev)
353{
354 struct platform_device *pdev = to_platform_device(dev);
355 int ret;
356
357 ret = pm_generic_runtime_suspend(dev);
358 if (ret)
359 return ret;
360
361 return omap_device_idle(pdev);
362}
363
364static int _od_runtime_resume(struct device *dev)
365{
366 struct platform_device *pdev = to_platform_device(dev);
367 int ret;
368
369 ret = omap_device_enable(pdev);
370 if (ret) {
371 dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
372 return ret;
373 }
374
375 return pm_generic_runtime_resume(dev);
376}
377
378static int _od_fail_runtime_suspend(struct device *dev)
379{
380 dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
381 return -ENODEV;
382}
383
384static int _od_fail_runtime_resume(struct device *dev)
385{
386 dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
387 return -ENODEV;
388}
389
390#endif
391
392#ifdef CONFIG_SUSPEND
393static int _od_suspend_noirq(struct device *dev)
394{
395 struct platform_device *pdev = to_platform_device(dev);
396 struct omap_device *od = to_omap_device(pdev);
397 int ret;
398
399 /* Don't attempt late suspend on a driver that is not bound */
400 if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
401 return 0;
402
403 ret = pm_generic_suspend_noirq(dev);
404
405 if (!ret && !pm_runtime_status_suspended(dev)) {
406 if (pm_generic_runtime_suspend(dev) == 0) {
407 omap_device_idle(pdev);
408 od->flags |= OMAP_DEVICE_SUSPENDED;
409 }
410 }
411
412 return ret;
413}
414
415static int _od_resume_noirq(struct device *dev)
416{
417 struct platform_device *pdev = to_platform_device(dev);
418 struct omap_device *od = to_omap_device(pdev);
419
420 if (od->flags & OMAP_DEVICE_SUSPENDED) {
421 od->flags &= ~OMAP_DEVICE_SUSPENDED;
422 omap_device_enable(pdev);
423 pm_generic_runtime_resume(dev);
424 }
425
426 return pm_generic_resume_noirq(dev);
427}
428#else
429#define _od_suspend_noirq NULL
430#define _od_resume_noirq NULL
431#endif
432
433static struct dev_pm_domain omap_device_fail_pm_domain = {
434 .ops = {
435 SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
436 _od_fail_runtime_resume, NULL)
437 }
438};
439
440static struct dev_pm_domain omap_device_pm_domain = {
441 .ops = {
442 SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
443 NULL)
444 USE_PLATFORM_PM_SLEEP_OPS
445 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
446 _od_resume_noirq)
447 }
448};
449
450/* Public functions for use by device drivers through struct platform_data */
451
452/**
453 * omap_device_enable - fully activate an omap_device
454 * @pdev: the platform device to activate
455 *
456 * Do whatever is necessary for the hwmods underlying omap_device @od
457 * to be accessible and ready to operate. This generally involves
458 * enabling clocks, setting SYSCONFIG registers; and in the future may
459 * involve remuxing pins. Device drivers should call this function
460 * indirectly via pm_runtime_get*(). Returns -EINVAL if called when
461 * the omap_device is already enabled, or passes along the return
462 * value of _omap_device_enable_hwmods().
463 */
464int omap_device_enable(struct platform_device *pdev)
465{
466 int ret;
467 struct omap_device *od;
468
469 od = to_omap_device(pdev);
470
471 if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
472 dev_warn(&pdev->dev,
473 "omap_device: %s() called from invalid state %d\n",
474 __func__, od->_state);
475 return -EINVAL;
476 }
477
478 ret = _omap_device_enable_hwmods(od);
479
480 if (ret == 0)
481 od->_state = OMAP_DEVICE_STATE_ENABLED;
482
483 return ret;
484}
485
486/**
487 * omap_device_idle - idle an omap_device
488 * @pdev: The platform_device (omap_device) to idle
489 *
490 * Idle omap_device @od. Device drivers call this function indirectly
491 * via pm_runtime_put*(). Returns -EINVAL if the omap_device is not
492 * currently enabled, or passes along the return value of
493 * _omap_device_idle_hwmods().
494 */
495int omap_device_idle(struct platform_device *pdev)
496{
497 int ret;
498 struct omap_device *od;
499
500 od = to_omap_device(pdev);
501
502 if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
503 dev_warn(&pdev->dev,
504 "omap_device: %s() called from invalid state %d\n",
505 __func__, od->_state);
506 return -EINVAL;
507 }
508
509 ret = _omap_device_idle_hwmods(od);
510
511 if (ret == 0)
512 od->_state = OMAP_DEVICE_STATE_IDLE;
513
514 return ret;
515}
516
517/**
518 * omap_device_assert_hardreset - set a device's hardreset line
519 * @pdev: struct platform_device * to reset
520 * @name: const char * name of the reset line
521 *
522 * Set the hardreset line identified by @name on the IP blocks
523 * associated with the hwmods backing the platform_device @pdev. All
524 * of the hwmods associated with @pdev must have the same hardreset
525 * line linked to them for this to work. Passes along the return value
526 * of omap_hwmod_assert_hardreset() in the event of any failure, or
527 * returns 0 upon success.
528 */
529int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
530{
531 struct omap_device *od = to_omap_device(pdev);
532 int ret = 0;
533 int i;
534
535 for (i = 0; i < od->hwmods_cnt; i++) {
536 ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
537 if (ret)
538 break;
539 }
540
541 return ret;
542}
543
544/**
545 * omap_device_deassert_hardreset - release a device's hardreset line
546 * @pdev: struct platform_device * to reset
547 * @name: const char * name of the reset line
548 *
549 * Release the hardreset line identified by @name on the IP blocks
550 * associated with the hwmods backing the platform_device @pdev. All
551 * of the hwmods associated with @pdev must have the same hardreset
552 * line linked to them for this to work. Passes along the return
553 * value of omap_hwmod_deassert_hardreset() in the event of any
554 * failure, or returns 0 upon success.
555 */
556int omap_device_deassert_hardreset(struct platform_device *pdev,
557 const char *name)
558{
559 struct omap_device *od = to_omap_device(pdev);
560 int ret = 0;
561 int i;
562
563 for (i = 0; i < od->hwmods_cnt; i++) {
564 ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
565 if (ret)
566 break;
567 }
568
569 return ret;
570}
571
572static struct notifier_block platform_nb = {
573 .notifier_call = _omap_device_notifier_call,
574};
575
576static int __init omap_device_init(void)
577{
578 bus_register_notifier(bus: &platform_bus_type, nb: &platform_nb);
579 return 0;
580}
581omap_postcore_initcall(omap_device_init);
582
583/**
584 * omap_device_late_idle - idle devices without drivers
585 * @dev: struct device * associated with omap_device
586 * @data: unused
587 *
588 * Check the driver bound status of this device, and idle it
589 * if there is no driver attached.
590 */
591static int __init omap_device_late_idle(struct device *dev, void *data)
592{
593 struct platform_device *pdev = to_platform_device(dev);
594 struct omap_device *od = to_omap_device(pdev);
595 int i;
596
597 if (!od)
598 return 0;
599
600 /*
601 * If omap_device state is enabled, but has no driver bound,
602 * idle it.
603 */
604
605 /*
606 * Some devices (like memory controllers) are always kept
607 * enabled, and should not be idled even with no drivers.
608 */
609 for (i = 0; i < od->hwmods_cnt; i++)
610 if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
611 return 0;
612
613 if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
614 od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
615 if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
616 dev_warn(dev, "%s: enabled but no driver. Idling\n",
617 __func__);
618 omap_device_idle(pdev);
619 }
620 }
621
622 return 0;
623}
624
625static int __init omap_device_late_init(void)
626{
627 bus_for_each_dev(bus: &platform_bus_type, NULL, NULL, fn: omap_device_late_idle);
628
629 return 0;
630}
631omap_late_initcall_sync(omap_device_late_init);
632

source code of linux/arch/arm/mach-omap2/omap_device.c