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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.
4 */
5#include <linux/kernel.h>
6#include <linux/errno.h>
7#include <linux/idr.h>
8#include <linux/slab.h>
9#include <linux/module.h>
10#include <linux/of.h>
11#include <linux/of_device.h>
12#include <linux/platform_device.h>
13#include <linux/spmi.h>
14#include <linux/pm_runtime.h>
15
16#include <dt-bindings/spmi/spmi.h>
17#define CREATE_TRACE_POINTS
18#include <trace/events/spmi.h>
19
20static bool is_registered;
21static DEFINE_IDA(ctrl_ida);
22
23static void spmi_dev_release(struct device *dev)
24{
25 struct spmi_device *sdev = to_spmi_device(dev);
26
27 kfree(sdev);
28}
29
30static const struct device_type spmi_dev_type = {
31 .release = spmi_dev_release,
32};
33
34static void spmi_ctrl_release(struct device *dev)
35{
36 struct spmi_controller *ctrl = to_spmi_controller(dev);
37
38 ida_free(&ctrl_ida, ctrl->nr);
39 kfree(ctrl);
40}
41
42static const struct device_type spmi_ctrl_type = {
43 .release = spmi_ctrl_release,
44};
45
46static int spmi_device_match(struct device *dev, struct device_driver *drv)
47{
48 if (of_driver_match_device(dev, drv))
49 return 1;
50
51 if (drv->name)
52 return strncmp(dev_name(dev), drv->name,
53 SPMI_NAME_SIZE) == 0;
54
55 return 0;
56}
57
58/**
59 * spmi_device_add() - add a device previously constructed via spmi_device_alloc()
60 * @sdev: spmi_device to be added
61 */
62int spmi_device_add(struct spmi_device *sdev)
63{
64 struct spmi_controller *ctrl = sdev->ctrl;
65 int err;
66
67 dev_set_name(&sdev->dev, "%d-%02x", ctrl->nr, sdev->usid);
68
69 err = device_add(&sdev->dev);
70 if (err < 0) {
71 dev_err(&sdev->dev, "Can't add %s, status %d\n",
72 dev_name(&sdev->dev), err);
73 goto err_device_add;
74 }
75
76 dev_dbg(&sdev->dev, "device %s registered\n", dev_name(&sdev->dev));
77
78err_device_add:
79 return err;
80}
81EXPORT_SYMBOL_GPL(spmi_device_add);
82
83/**
84 * spmi_device_remove(): remove an SPMI device
85 * @sdev: spmi_device to be removed
86 */
87void spmi_device_remove(struct spmi_device *sdev)
88{
89 device_unregister(&sdev->dev);
90}
91EXPORT_SYMBOL_GPL(spmi_device_remove);
92
93static inline int
94spmi_cmd(struct spmi_controller *ctrl, u8 opcode, u8 sid)
95{
96 int ret;
97
98 if (!ctrl || !ctrl->cmd || ctrl->dev.type != &spmi_ctrl_type)
99 return -EINVAL;
100
101 ret = ctrl->cmd(ctrl, opcode, sid);
102 trace_spmi_cmd(opcode, sid, ret);
103 return ret;
104}
105
106static inline int spmi_read_cmd(struct spmi_controller *ctrl, u8 opcode,
107 u8 sid, u16 addr, u8 *buf, size_t len)
108{
109 int ret;
110
111 if (!ctrl || !ctrl->read_cmd || ctrl->dev.type != &spmi_ctrl_type)
112 return -EINVAL;
113
114 trace_spmi_read_begin(opcode, sid, addr);
115 ret = ctrl->read_cmd(ctrl, opcode, sid, addr, buf, len);
116 trace_spmi_read_end(opcode, sid, addr, ret, len, buf);
117 return ret;
118}
119
120static inline int spmi_write_cmd(struct spmi_controller *ctrl, u8 opcode,
121 u8 sid, u16 addr, const u8 *buf, size_t len)
122{
123 int ret;
124
125 if (!ctrl || !ctrl->write_cmd || ctrl->dev.type != &spmi_ctrl_type)
126 return -EINVAL;
127
128 trace_spmi_write_begin(opcode, sid, addr, len, buf);
129 ret = ctrl->write_cmd(ctrl, opcode, sid, addr, buf, len);
130 trace_spmi_write_end(opcode, sid, addr, ret);
131 return ret;
132}
133
134/**
135 * spmi_register_read() - register read
136 * @sdev: SPMI device.
137 * @addr: slave register address (5-bit address).
138 * @buf: buffer to be populated with data from the Slave.
139 *
140 * Reads 1 byte of data from a Slave device register.
141 */
142int spmi_register_read(struct spmi_device *sdev, u8 addr, u8 *buf)
143{
144 /* 5-bit register address */
145 if (addr > 0x1F)
146 return -EINVAL;
147
148 return spmi_read_cmd(sdev->ctrl, SPMI_CMD_READ, sdev->usid, addr,
149 buf, 1);
150}
151EXPORT_SYMBOL_GPL(spmi_register_read);
152
153/**
154 * spmi_ext_register_read() - extended register read
155 * @sdev: SPMI device.
156 * @addr: slave register address (8-bit address).
157 * @buf: buffer to be populated with data from the Slave.
158 * @len: the request number of bytes to read (up to 16 bytes).
159 *
160 * Reads up to 16 bytes of data from the extended register space on a
161 * Slave device.
162 */
163int spmi_ext_register_read(struct spmi_device *sdev, u8 addr, u8 *buf,
164 size_t len)
165{
166 /* 8-bit register address, up to 16 bytes */
167 if (len == 0 || len > 16)
168 return -EINVAL;
169
170 return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READ, sdev->usid, addr,
171 buf, len);
172}
173EXPORT_SYMBOL_GPL(spmi_ext_register_read);
174
175/**
176 * spmi_ext_register_readl() - extended register read long
177 * @sdev: SPMI device.
178 * @addr: slave register address (16-bit address).
179 * @buf: buffer to be populated with data from the Slave.
180 * @len: the request number of bytes to read (up to 8 bytes).
181 *
182 * Reads up to 8 bytes of data from the extended register space on a
183 * Slave device using 16-bit address.
184 */
185int spmi_ext_register_readl(struct spmi_device *sdev, u16 addr, u8 *buf,
186 size_t len)
187{
188 /* 16-bit register address, up to 8 bytes */
189 if (len == 0 || len > 8)
190 return -EINVAL;
191
192 return spmi_read_cmd(sdev->ctrl, SPMI_CMD_EXT_READL, sdev->usid, addr,
193 buf, len);
194}
195EXPORT_SYMBOL_GPL(spmi_ext_register_readl);
196
197/**
198 * spmi_register_write() - register write
199 * @sdev: SPMI device
200 * @addr: slave register address (5-bit address).
201 * @data: buffer containing the data to be transferred to the Slave.
202 *
203 * Writes 1 byte of data to a Slave device register.
204 */
205int spmi_register_write(struct spmi_device *sdev, u8 addr, u8 data)
206{
207 /* 5-bit register address */
208 if (addr > 0x1F)
209 return -EINVAL;
210
211 return spmi_write_cmd(sdev->ctrl, SPMI_CMD_WRITE, sdev->usid, addr,
212 &data, 1);
213}
214EXPORT_SYMBOL_GPL(spmi_register_write);
215
216/**
217 * spmi_register_zero_write() - register zero write
218 * @sdev: SPMI device.
219 * @data: the data to be written to register 0 (7-bits).
220 *
221 * Writes data to register 0 of the Slave device.
222 */
223int spmi_register_zero_write(struct spmi_device *sdev, u8 data)
224{
225 return spmi_write_cmd(sdev->ctrl, SPMI_CMD_ZERO_WRITE, sdev->usid, 0,
226 &data, 1);
227}
228EXPORT_SYMBOL_GPL(spmi_register_zero_write);
229
230/**
231 * spmi_ext_register_write() - extended register write
232 * @sdev: SPMI device.
233 * @addr: slave register address (8-bit address).
234 * @buf: buffer containing the data to be transferred to the Slave.
235 * @len: the request number of bytes to read (up to 16 bytes).
236 *
237 * Writes up to 16 bytes of data to the extended register space of a
238 * Slave device.
239 */
240int spmi_ext_register_write(struct spmi_device *sdev, u8 addr, const u8 *buf,
241 size_t len)
242{
243 /* 8-bit register address, up to 16 bytes */
244 if (len == 0 || len > 16)
245 return -EINVAL;
246
247 return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITE, sdev->usid, addr,
248 buf, len);
249}
250EXPORT_SYMBOL_GPL(spmi_ext_register_write);
251
252/**
253 * spmi_ext_register_writel() - extended register write long
254 * @sdev: SPMI device.
255 * @addr: slave register address (16-bit address).
256 * @buf: buffer containing the data to be transferred to the Slave.
257 * @len: the request number of bytes to read (up to 8 bytes).
258 *
259 * Writes up to 8 bytes of data to the extended register space of a
260 * Slave device using 16-bit address.
261 */
262int spmi_ext_register_writel(struct spmi_device *sdev, u16 addr, const u8 *buf,
263 size_t len)
264{
265 /* 4-bit Slave Identifier, 16-bit register address, up to 8 bytes */
266 if (len == 0 || len > 8)
267 return -EINVAL;
268
269 return spmi_write_cmd(sdev->ctrl, SPMI_CMD_EXT_WRITEL, sdev->usid,
270 addr, buf, len);
271}
272EXPORT_SYMBOL_GPL(spmi_ext_register_writel);
273
274/**
275 * spmi_command_reset() - sends RESET command to the specified slave
276 * @sdev: SPMI device.
277 *
278 * The Reset command initializes the Slave and forces all registers to
279 * their reset values. The Slave shall enter the STARTUP state after
280 * receiving a Reset command.
281 */
282int spmi_command_reset(struct spmi_device *sdev)
283{
284 return spmi_cmd(sdev->ctrl, SPMI_CMD_RESET, sdev->usid);
285}
286EXPORT_SYMBOL_GPL(spmi_command_reset);
287
288/**
289 * spmi_command_sleep() - sends SLEEP command to the specified SPMI device
290 * @sdev: SPMI device.
291 *
292 * The Sleep command causes the Slave to enter the user defined SLEEP state.
293 */
294int spmi_command_sleep(struct spmi_device *sdev)
295{
296 return spmi_cmd(sdev->ctrl, SPMI_CMD_SLEEP, sdev->usid);
297}
298EXPORT_SYMBOL_GPL(spmi_command_sleep);
299
300/**
301 * spmi_command_wakeup() - sends WAKEUP command to the specified SPMI device
302 * @sdev: SPMI device.
303 *
304 * The Wakeup command causes the Slave to move from the SLEEP state to
305 * the ACTIVE state.
306 */
307int spmi_command_wakeup(struct spmi_device *sdev)
308{
309 return spmi_cmd(sdev->ctrl, SPMI_CMD_WAKEUP, sdev->usid);
310}
311EXPORT_SYMBOL_GPL(spmi_command_wakeup);
312
313/**
314 * spmi_command_shutdown() - sends SHUTDOWN command to the specified SPMI device
315 * @sdev: SPMI device.
316 *
317 * The Shutdown command causes the Slave to enter the SHUTDOWN state.
318 */
319int spmi_command_shutdown(struct spmi_device *sdev)
320{
321 return spmi_cmd(sdev->ctrl, SPMI_CMD_SHUTDOWN, sdev->usid);
322}
323EXPORT_SYMBOL_GPL(spmi_command_shutdown);
324
325static int spmi_drv_probe(struct device *dev)
326{
327 const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);
328 struct spmi_device *sdev = to_spmi_device(dev);
329 int err;
330
331 pm_runtime_get_noresume(dev);
332 pm_runtime_set_active(dev);
333 pm_runtime_enable(dev);
334
335 err = sdrv->probe(sdev);
336 if (err)
337 goto fail_probe;
338
339 return 0;
340
341fail_probe:
342 pm_runtime_disable(dev);
343 pm_runtime_set_suspended(dev);
344 pm_runtime_put_noidle(dev);
345 return err;
346}
347
348static void spmi_drv_remove(struct device *dev)
349{
350 const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);
351
352 pm_runtime_get_sync(dev);
353 sdrv->remove(to_spmi_device(dev));
354 pm_runtime_put_noidle(dev);
355
356 pm_runtime_disable(dev);
357 pm_runtime_set_suspended(dev);
358 pm_runtime_put_noidle(dev);
359}
360
361static void spmi_drv_shutdown(struct device *dev)
362{
363 const struct spmi_driver *sdrv = to_spmi_driver(dev->driver);
364
365 if (sdrv && sdrv->shutdown)
366 sdrv->shutdown(to_spmi_device(dev));
367}
368
369static int spmi_drv_uevent(struct device *dev, struct kobj_uevent_env *env)
370{
371 int ret;
372
373 ret = of_device_uevent_modalias(dev, env);
374 if (ret != -ENODEV)
375 return ret;
376
377 return 0;
378}
379
380static struct bus_type spmi_bus_type = {
381 .name = "spmi",
382 .match = spmi_device_match,
383 .probe = spmi_drv_probe,
384 .remove = spmi_drv_remove,
385 .shutdown = spmi_drv_shutdown,
386 .uevent = spmi_drv_uevent,
387};
388
389/**
390 * spmi_device_from_of() - get the associated SPMI device from a device node
391 *
392 * @np: device node
393 *
394 * Returns the struct spmi_device associated with a device node or NULL.
395 */
396struct spmi_device *spmi_device_from_of(struct device_node *np)
397{
398 struct device *dev = bus_find_device_by_of_node(&spmi_bus_type, np);
399
400 if (dev)
401 return to_spmi_device(dev);
402 return NULL;
403}
404EXPORT_SYMBOL_GPL(spmi_device_from_of);
405
406/**
407 * spmi_controller_alloc() - Allocate a new SPMI device
408 * @ctrl: associated controller
409 *
410 * Caller is responsible for either calling spmi_device_add() to add the
411 * newly allocated controller, or calling spmi_device_put() to discard it.
412 */
413struct spmi_device *spmi_device_alloc(struct spmi_controller *ctrl)
414{
415 struct spmi_device *sdev;
416
417 sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
418 if (!sdev)
419 return NULL;
420
421 sdev->ctrl = ctrl;
422 device_initialize(&sdev->dev);
423 sdev->dev.parent = &ctrl->dev;
424 sdev->dev.bus = &spmi_bus_type;
425 sdev->dev.type = &spmi_dev_type;
426 return sdev;
427}
428EXPORT_SYMBOL_GPL(spmi_device_alloc);
429
430/**
431 * spmi_controller_alloc() - Allocate a new SPMI controller
432 * @parent: parent device
433 * @size: size of private data
434 *
435 * Caller is responsible for either calling spmi_controller_add() to add the
436 * newly allocated controller, or calling spmi_controller_put() to discard it.
437 * The allocated private data region may be accessed via
438 * spmi_controller_get_drvdata()
439 */
440struct spmi_controller *spmi_controller_alloc(struct device *parent,
441 size_t size)
442{
443 struct spmi_controller *ctrl;
444 int id;
445
446 if (WARN_ON(!parent))
447 return NULL;
448
449 ctrl = kzalloc(sizeof(*ctrl) + size, GFP_KERNEL);
450 if (!ctrl)
451 return NULL;
452
453 device_initialize(&ctrl->dev);
454 ctrl->dev.type = &spmi_ctrl_type;
455 ctrl->dev.bus = &spmi_bus_type;
456 ctrl->dev.parent = parent;
457 ctrl->dev.of_node = parent->of_node;
458 spmi_controller_set_drvdata(ctrl, &ctrl[1]);
459
460 id = ida_alloc(&ctrl_ida, GFP_KERNEL);
461 if (id < 0) {
462 dev_err(parent,
463 "unable to allocate SPMI controller identifier.\n");
464 spmi_controller_put(ctrl);
465 return NULL;
466 }
467
468 ctrl->nr = id;
469 dev_set_name(&ctrl->dev, "spmi-%d", id);
470
471 dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);
472 return ctrl;
473}
474EXPORT_SYMBOL_GPL(spmi_controller_alloc);
475
476static void of_spmi_register_devices(struct spmi_controller *ctrl)
477{
478 struct device_node *node;
479 int err;
480
481 if (!ctrl->dev.of_node)
482 return;
483
484 for_each_available_child_of_node(ctrl->dev.of_node, node) {
485 struct spmi_device *sdev;
486 u32 reg[2];
487
488 dev_dbg(&ctrl->dev, "adding child %pOF\n", node);
489
490 err = of_property_read_u32_array(node, "reg", reg, 2);
491 if (err) {
492 dev_err(&ctrl->dev,
493 "node %pOF err (%d) does not have 'reg' property\n",
494 node, err);
495 continue;
496 }
497
498 if (reg[1] != SPMI_USID) {
499 dev_err(&ctrl->dev,
500 "node %pOF contains unsupported 'reg' entry\n",
501 node);
502 continue;
503 }
504
505 if (reg[0] >= SPMI_MAX_SLAVE_ID) {
506 dev_err(&ctrl->dev, "invalid usid on node %pOF\n", node);
507 continue;
508 }
509
510 dev_dbg(&ctrl->dev, "read usid %02x\n", reg[0]);
511
512 sdev = spmi_device_alloc(ctrl);
513 if (!sdev)
514 continue;
515
516 sdev->dev.of_node = node;
517 sdev->usid = (u8)reg[0];
518
519 err = spmi_device_add(sdev);
520 if (err) {
521 dev_err(&sdev->dev,
522 "failure adding device. status %d\n", err);
523 spmi_device_put(sdev);
524 }
525 }
526}
527
528/**
529 * spmi_controller_add() - Add an SPMI controller
530 * @ctrl: controller to be registered.
531 *
532 * Register a controller previously allocated via spmi_controller_alloc() with
533 * the SPMI core.
534 */
535int spmi_controller_add(struct spmi_controller *ctrl)
536{
537 int ret;
538
539 /* Can't register until after driver model init */
540 if (WARN_ON(!is_registered))
541 return -EAGAIN;
542
543 ret = device_add(&ctrl->dev);
544 if (ret)
545 return ret;
546
547 if (IS_ENABLED(CONFIG_OF))
548 of_spmi_register_devices(ctrl);
549
550 dev_dbg(&ctrl->dev, "spmi-%d registered: dev:%p\n",
551 ctrl->nr, &ctrl->dev);
552
553 return 0;
554};
555EXPORT_SYMBOL_GPL(spmi_controller_add);
556
557/* Remove a device associated with a controller */
558static int spmi_ctrl_remove_device(struct device *dev, void *data)
559{
560 struct spmi_device *spmidev = to_spmi_device(dev);
561
562 if (dev->type == &spmi_dev_type)
563 spmi_device_remove(spmidev);
564 return 0;
565}
566
567/**
568 * spmi_controller_remove(): remove an SPMI controller
569 * @ctrl: controller to remove
570 *
571 * Remove a SPMI controller. Caller is responsible for calling
572 * spmi_controller_put() to discard the allocated controller.
573 */
574void spmi_controller_remove(struct spmi_controller *ctrl)
575{
576 if (!ctrl)
577 return;
578
579 device_for_each_child(&ctrl->dev, NULL, spmi_ctrl_remove_device);
580 device_del(&ctrl->dev);
581}
582EXPORT_SYMBOL_GPL(spmi_controller_remove);
583
584/**
585 * spmi_driver_register() - Register client driver with SPMI core
586 * @sdrv: client driver to be associated with client-device.
587 *
588 * This API will register the client driver with the SPMI framework.
589 * It is typically called from the driver's module-init function.
590 */
591int __spmi_driver_register(struct spmi_driver *sdrv, struct module *owner)
592{
593 sdrv->driver.bus = &spmi_bus_type;
594 sdrv->driver.owner = owner;
595 return driver_register(&sdrv->driver);
596}
597EXPORT_SYMBOL_GPL(__spmi_driver_register);
598
599static void __exit spmi_exit(void)
600{
601 bus_unregister(&spmi_bus_type);
602}
603module_exit(spmi_exit);
604
605static int __init spmi_init(void)
606{
607 int ret;
608
609 ret = bus_register(&spmi_bus_type);
610 if (ret)
611 return ret;
612
613 is_registered = true;
614 return 0;
615}
616postcore_initcall(spmi_init);
617
618MODULE_LICENSE("GPL v2");
619MODULE_DESCRIPTION("SPMI module");
620MODULE_ALIAS("platform:spmi");