summaryrefslogtreecommitdiff
path: root/drivers/input/rmi4/rmi_bus.c
blob: ef7a66230d83c8d59ba4f88ae980a5642c34a84d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
/*
 * Copyright (c) 2011-2016 Synaptics Incorporated
 * Copyright (c) 2011 Unixphere
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/kconfig.h>
#include <linux/list.h>
#include <linux/pm.h>
#include <linux/rmi.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/of.h>
#include "rmi_bus.h"
#include "rmi_driver.h"

static int debug_flags;
module_param(debug_flags, int, 0644);
MODULE_PARM_DESC(debug_flags, "control debugging information");

void rmi_dbg(int flags, struct device *dev, const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;

	if (flags & debug_flags) {
		va_start(args, fmt);

		vaf.fmt = fmt;
		vaf.va = &args;

		dev_printk(KERN_DEBUG, dev, "%pV", &vaf);

		va_end(args);
	}
}
EXPORT_SYMBOL_GPL(rmi_dbg);

/*
 * RMI Physical devices
 *
 * Physical RMI device consists of several functions serving particular
 * purpose. For example F11 is a 2D touch sensor while F01 is a generic
 * function present in every RMI device.
 */

static void rmi_release_device(struct device *dev)
{
	struct rmi_device *rmi_dev = to_rmi_device(dev);

	kfree(rmi_dev);
}

static struct device_type rmi_device_type = {
	.name		= "rmi4_sensor",
	.release	= rmi_release_device,
};

bool rmi_is_physical_device(struct device *dev)
{
	return dev->type == &rmi_device_type;
}

/**
 * rmi_register_transport_device - register a transport device connection
 * on the RMI bus.  Transport drivers provide communication from the devices
 * on a bus (such as SPI, I2C, and so on) to the RMI4 sensor.
 *
 * @xport: the transport device to register
 */
int rmi_register_transport_device(struct rmi_transport_dev *xport)
{
	static atomic_t transport_device_count = ATOMIC_INIT(0);
	struct rmi_device *rmi_dev;
	int error;

	rmi_dev = kzalloc(sizeof(struct rmi_device), GFP_KERNEL);
	if (!rmi_dev)
		return -ENOMEM;

	device_initialize(&rmi_dev->dev);

	rmi_dev->xport = xport;
	rmi_dev->number = atomic_inc_return(&transport_device_count) - 1;

	dev_set_name(&rmi_dev->dev, "rmi4-%02d", rmi_dev->number);

	rmi_dev->dev.bus = &rmi_bus_type;
	rmi_dev->dev.type = &rmi_device_type;

	xport->rmi_dev = rmi_dev;

	error = device_add(&rmi_dev->dev);
	if (error)
		goto err_put_device;

	rmi_dbg(RMI_DEBUG_CORE, xport->dev,
		"%s: Registered %s as %s.\n", __func__,
		dev_name(rmi_dev->xport->dev), dev_name(&rmi_dev->dev));

	return 0;

err_put_device:
	put_device(&rmi_dev->dev);
	return error;
}
EXPORT_SYMBOL_GPL(rmi_register_transport_device);

/**
 * rmi_unregister_transport_device - unregister a transport device connection
 * @xport: the transport driver to unregister
 *
 */
void rmi_unregister_transport_device(struct rmi_transport_dev *xport)
{
	struct rmi_device *rmi_dev = xport->rmi_dev;

	device_del(&rmi_dev->dev);
	put_device(&rmi_dev->dev);
}
EXPORT_SYMBOL(rmi_unregister_transport_device);


/* Function specific stuff */

static void rmi_release_function(struct device *dev)
{
	struct rmi_function *fn = to_rmi_function(dev);

	kfree(fn);
}

static struct device_type rmi_function_type = {
	.name		= "rmi4_function",
	.release	= rmi_release_function,
};

bool rmi_is_function_device(struct device *dev)
{
	return dev->type == &rmi_function_type;
}

static int rmi_function_match(struct device *dev, struct device_driver *drv)
{
	struct rmi_function_handler *handler = to_rmi_function_handler(drv);
	struct rmi_function *fn = to_rmi_function(dev);

	return fn->fd.function_number == handler->func;
}

#ifdef CONFIG_OF
static void rmi_function_of_probe(struct rmi_function *fn)
{
	char of_name[9];
	struct device_node *node = fn->rmi_dev->xport->dev->of_node;

	snprintf(of_name, sizeof(of_name), "rmi4-f%02x",
		fn->fd.function_number);
	fn->dev.of_node = of_get_child_by_name(node, of_name);
}
#else
static inline void rmi_function_of_probe(struct rmi_function *fn)
{}
#endif

static int rmi_function_probe(struct device *dev)
{
	struct rmi_function *fn = to_rmi_function(dev);
	struct rmi_function_handler *handler =
					to_rmi_function_handler(dev->driver);
	int error;

	rmi_function_of_probe(fn);

	if (handler->probe) {
		error = handler->probe(fn);
		return error;
	}

	return 0;
}

static int rmi_function_remove(struct device *dev)
{
	struct rmi_function *fn = to_rmi_function(dev);
	struct rmi_function_handler *handler =
					to_rmi_function_handler(dev->driver);

	if (handler->remove)
		handler->remove(fn);

	return 0;
}

int rmi_register_function(struct rmi_function *fn)
{
	struct rmi_device *rmi_dev = fn->rmi_dev;
	int error;

	device_initialize(&fn->dev);

	dev_set_name(&fn->dev, "%s.fn%02x",
		     dev_name(&rmi_dev->dev), fn->fd.function_number);

	fn->dev.parent = &rmi_dev->dev;
	fn->dev.type = &rmi_function_type;
	fn->dev.bus = &rmi_bus_type;

	error = device_add(&fn->dev);
	if (error) {
		dev_err(&rmi_dev->dev,
			"Failed device_register function device %s\n",
			dev_name(&fn->dev));
		goto err_put_device;
	}

	rmi_dbg(RMI_DEBUG_CORE, &rmi_dev->dev, "Registered F%02X.\n",
			fn->fd.function_number);

	return 0;

err_put_device:
	put_device(&fn->dev);
	return error;
}

void rmi_unregister_function(struct rmi_function *fn)
{
	rmi_dbg(RMI_DEBUG_CORE, &fn->dev, "Unregistering F%02X.\n",
			fn->fd.function_number);

	device_del(&fn->dev);
	of_node_put(fn->dev.of_node);
	put_device(&fn->dev);
}

/**
 * rmi_register_function_handler - register a handler for an RMI function
 * @handler: RMI handler that should be registered.
 * @module: pointer to module that implements the handler
 * @mod_name: name of the module implementing the handler
 *
 * This function performs additional setup of RMI function handler and
 * registers it with the RMI core so that it can be bound to
 * RMI function devices.
 */
int __rmi_register_function_handler(struct rmi_function_handler *handler,
				     struct module *owner,
				     const char *mod_name)
{
	struct device_driver *driver = &handler->driver;
	int error;

	driver->bus = &rmi_bus_type;
	driver->owner = owner;
	driver->mod_name = mod_name;
	driver->probe = rmi_function_probe;
	driver->remove = rmi_function_remove;

	error = driver_register(&handler->driver);
	if (error) {
		pr_err("driver_register() failed for %s, error: %d\n",
			handler->driver.name, error);
		return error;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(__rmi_register_function_handler);

/**
 * rmi_unregister_function_handler - unregister given RMI function handler
 * @handler: RMI handler that should be unregistered.
 *
 * This function unregisters given function handler from RMI core which
 * causes it to be unbound from the function devices.
 */
void rmi_unregister_function_handler(struct rmi_function_handler *handler)
{
	driver_unregister(&handler->driver);
}
EXPORT_SYMBOL_GPL(rmi_unregister_function_handler);

/* Bus specific stuff */

static int rmi_bus_match(struct device *dev, struct device_driver *drv)
{
	bool physical = rmi_is_physical_device(dev);

	/* First see if types are not compatible */
	if (physical != rmi_is_physical_driver(drv))
		return 0;

	return physical || rmi_function_match(dev, drv);
}

struct bus_type rmi_bus_type = {
	.match		= rmi_bus_match,
	.name		= "rmi4",
};

static struct rmi_function_handler *fn_handlers[] = {
	&rmi_f01_handler,
#ifdef CONFIG_RMI4_F11
	&rmi_f11_handler,
#endif
#ifdef CONFIG_RMI4_F12
	&rmi_f12_handler,
#endif
#ifdef CONFIG_RMI4_F30
	&rmi_f30_handler,
#endif
#ifdef CONFIG_RMI4_F34
	&rmi_f34_handler,
#endif
#ifdef CONFIG_RMI4_F54
	&rmi_f54_handler,
#endif
};

static void __rmi_unregister_function_handlers(int start_idx)
{
	int i;

	for (i = start_idx; i >= 0; i--)
		rmi_unregister_function_handler(fn_handlers[i]);
}

static void rmi_unregister_function_handlers(void)
{
	__rmi_unregister_function_handlers(ARRAY_SIZE(fn_handlers) - 1);
}

static int rmi_register_function_handlers(void)
{
	int ret;
	int i;

	for (i = 0; i < ARRAY_SIZE(fn_handlers); i++)	{
		ret = rmi_register_function_handler(fn_handlers[i]);
		if (ret) {
			pr_err("%s: error registering the RMI F%02x handler: %d\n",
				__func__, fn_handlers[i]->func, ret);
			goto err_unregister_function_handlers;
		}
	}

	return 0;

err_unregister_function_handlers:
	__rmi_unregister_function_handlers(i - 1);
	return ret;
}

int rmi_of_property_read_u32(struct device *dev, u32 *result,
				const char *prop, bool optional)
{
	int retval;
	u32 val = 0;

	retval = of_property_read_u32(dev->of_node, prop, &val);
	if (retval && (!optional && retval == -EINVAL)) {
		dev_err(dev, "Failed to get %s value: %d\n",
			prop, retval);
		return retval;
	}
	*result = val;

	return 0;
}
EXPORT_SYMBOL_GPL(rmi_of_property_read_u32);

static int __init rmi_bus_init(void)
{
	int error;

	error = bus_register(&rmi_bus_type);
	if (error) {
		pr_err("%s: error registering the RMI bus: %d\n",
			__func__, error);
		return error;
	}

	error = rmi_register_function_handlers();
	if (error)
		goto err_unregister_bus;

	error = rmi_register_physical_driver();
	if (error) {
		pr_err("%s: error registering the RMI physical driver: %d\n",
			__func__, error);
		goto err_unregister_bus;
	}

	return 0;

err_unregister_bus:
	bus_unregister(&rmi_bus_type);
	return error;
}
module_init(rmi_bus_init);

static void __exit rmi_bus_exit(void)
{
	/*
	 * We should only ever get here if all drivers are unloaded, so
	 * all we have to do at this point is unregister ourselves.
	 */

	rmi_unregister_physical_driver();
	rmi_unregister_function_handlers();
	bus_unregister(&rmi_bus_type);
}
module_exit(rmi_bus_exit);

MODULE_AUTHOR("Christopher Heiny <cheiny@synaptics.com");
MODULE_AUTHOR("Andrew Duggan <aduggan@synaptics.com");
MODULE_DESCRIPTION("RMI bus");
MODULE_LICENSE("GPL");
MODULE_VERSION(RMI_DRIVER_VERSION);