[deliverable/linux.git] / drivers / platform / x86 / dell-rbtn.c

/*
    Dell Airplane Mode Switch driver
    Copyright (C) 2014-2015  Pali Rohár <pali.rohar@gmail.com>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
*/

#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/rfkill.h>
#include <linux/input.h>

enum rbtn_type {
	RBTN_UNKNOWN,
	RBTN_TOGGLE,
	RBTN_SLIDER,
};

struct rbtn_data {
	enum rbtn_type type;
	struct rfkill *rfkill;
	struct input_dev *input_dev;
};


/*
 * acpi functions
 */

static enum rbtn_type rbtn_check(struct acpi_device *device)
{
	unsigned long long output;
	acpi_status status;

	status = acpi_evaluate_integer(device->handle, "CRBT", NULL, &output);
	if (ACPI_FAILURE(status))
		return RBTN_UNKNOWN;

	switch (output) {
	case 0:
	case 1:
		return RBTN_TOGGLE;
	case 2:
	case 3:
		return RBTN_SLIDER;
	default:
		return RBTN_UNKNOWN;
	}
}

static int rbtn_get(struct acpi_device *device)
{
	unsigned long long output;
	acpi_status status;

	status = acpi_evaluate_integer(device->handle, "GRBT", NULL, &output);
	if (ACPI_FAILURE(status))
		return -EINVAL;

	return !output;
}

static int rbtn_acquire(struct acpi_device *device, bool enable)
{
	struct acpi_object_list input;
	union acpi_object param;
	acpi_status status;

	param.type = ACPI_TYPE_INTEGER;
	param.integer.value = enable;
	input.count = 1;
	input.pointer = &param;

	status = acpi_evaluate_object(device->handle, "ARBT", &input, NULL);
	if (ACPI_FAILURE(status))
		return -EINVAL;

	return 0;
}


/*
 * rfkill device
 */

static void rbtn_rfkill_query(struct rfkill *rfkill, void *data)
{
	struct acpi_device *device = data;
	int state;

	state = rbtn_get(device);
	if (state < 0)
		return;

	rfkill_set_states(rfkill, state, state);
}

static int rbtn_rfkill_set_block(void *data, bool blocked)
{
	/* NOTE: setting soft rfkill state is not supported */
	return -EINVAL;
}

static struct rfkill_ops rbtn_ops = {
	.query = rbtn_rfkill_query,
	.set_block = rbtn_rfkill_set_block,
};

static int rbtn_rfkill_init(struct acpi_device *device)
{
	struct rbtn_data *rbtn_data = device->driver_data;
	int ret;

	if (rbtn_data->rfkill)
		return 0;

	/*
	 * NOTE: rbtn controls all radio devices, not only WLAN
	 *       but rfkill interface does not support "ANY" type
	 *       so "WLAN" type is used
	 */
	rbtn_data->rfkill = rfkill_alloc("dell-rbtn", &device->dev,
					 RFKILL_TYPE_WLAN, &rbtn_ops, device);
	if (!rbtn_data->rfkill)
		return -ENOMEM;

	ret = rfkill_register(rbtn_data->rfkill);
	if (ret) {
		rfkill_destroy(rbtn_data->rfkill);
		rbtn_data->rfkill = NULL;
		return ret;
	}

	return 0;
}

static void rbtn_rfkill_exit(struct acpi_device *device)
{
	struct rbtn_data *rbtn_data = device->driver_data;

	if (!rbtn_data->rfkill)
		return;

	rfkill_unregister(rbtn_data->rfkill);
	rfkill_destroy(rbtn_data->rfkill);
	rbtn_data->rfkill = NULL;
}

static void rbtn_rfkill_event(struct acpi_device *device)
{
	struct rbtn_data *rbtn_data = device->driver_data;

	if (rbtn_data->rfkill)
		rbtn_rfkill_query(rbtn_data->rfkill, device);
}


/*
 * input device
 */

static int rbtn_input_init(struct rbtn_data *rbtn_data)
{
	int ret;

	rbtn_data->input_dev = input_allocate_device();
	if (!rbtn_data->input_dev)
		return -ENOMEM;

	rbtn_data->input_dev->name = "DELL Wireless hotkeys";
	rbtn_data->input_dev->phys = "dellabce/input0";
	rbtn_data->input_dev->id.bustype = BUS_HOST;
	rbtn_data->input_dev->evbit[0] = BIT(EV_KEY);
	set_bit(KEY_RFKILL, rbtn_data->input_dev->keybit);

	ret = input_register_device(rbtn_data->input_dev);
	if (ret) {
		input_free_device(rbtn_data->input_dev);
		rbtn_data->input_dev = NULL;
		return ret;
	}

	return 0;
}

static void rbtn_input_exit(struct rbtn_data *rbtn_data)
{
	input_unregister_device(rbtn_data->input_dev);
	rbtn_data->input_dev = NULL;
}

static void rbtn_input_event(struct rbtn_data *rbtn_data)
{
	input_report_key(rbtn_data->input_dev, KEY_RFKILL, 1);
	input_sync(rbtn_data->input_dev);
	input_report_key(rbtn_data->input_dev, KEY_RFKILL, 0);
	input_sync(rbtn_data->input_dev);
}


/*
 * acpi driver
 */

static int rbtn_add(struct acpi_device *device);
static int rbtn_remove(struct acpi_device *device);
static void rbtn_notify(struct acpi_device *device, u32 event);

static const struct acpi_device_id rbtn_ids[] = {
	{ "DELRBTN", 0 },
	{ "DELLABCE", 0 },
	{ "", 0 },
};

static struct acpi_driver rbtn_driver = {
	.name = "dell-rbtn",
	.ids = rbtn_ids,
	.ops = {
		.add = rbtn_add,
		.remove = rbtn_remove,
		.notify = rbtn_notify,
	},
	.owner = THIS_MODULE,
};


/*
 * notifier export functions
 */

static bool auto_remove_rfkill = true;

static ATOMIC_NOTIFIER_HEAD(rbtn_chain_head);

static int rbtn_inc_count(struct device *dev, void *data)
{
	struct acpi_device *device = to_acpi_device(dev);
	struct rbtn_data *rbtn_data = device->driver_data;
	int *count = data;

	if (rbtn_data->type == RBTN_SLIDER)
		(*count)++;

	return 0;
}

static int rbtn_switch_dev(struct device *dev, void *data)
{
	struct acpi_device *device = to_acpi_device(dev);
	struct rbtn_data *rbtn_data = device->driver_data;
	bool enable = data;

	if (rbtn_data->type != RBTN_SLIDER)
		return 0;

	if (enable)
		rbtn_rfkill_init(device);
	else
		rbtn_rfkill_exit(device);

	return 0;
}

int dell_rbtn_notifier_register(struct notifier_block *nb)
{
	bool first;
	int count;
	int ret;

	count = 0;
	ret = driver_for_each_device(&rbtn_driver.drv, NULL, &count,
				     rbtn_inc_count);
	if (ret || count == 0)
		return -ENODEV;

	first = !rbtn_chain_head.head;

	ret = atomic_notifier_chain_register(&rbtn_chain_head, nb);
	if (ret != 0)
		return ret;

	if (auto_remove_rfkill && first)
		ret = driver_for_each_device(&rbtn_driver.drv, NULL,
					     (void *)false, rbtn_switch_dev);

	return ret;
}
EXPORT_SYMBOL_GPL(dell_rbtn_notifier_register);

int dell_rbtn_notifier_unregister(struct notifier_block *nb)
{
	int ret;

	ret = atomic_notifier_chain_unregister(&rbtn_chain_head, nb);
	if (ret != 0)
		return ret;

	if (auto_remove_rfkill && !rbtn_chain_head.head)
		ret = driver_for_each_device(&rbtn_driver.drv, NULL,
					     (void *)true, rbtn_switch_dev);

	return ret;
}
EXPORT_SYMBOL_GPL(dell_rbtn_notifier_unregister);


/*
 * acpi driver functions
 */

static int rbtn_add(struct acpi_device *device)
{
	struct rbtn_data *rbtn_data;
	enum rbtn_type type;
	int ret = 0;

	type = rbtn_check(device);
	if (type == RBTN_UNKNOWN) {
		dev_info(&device->dev, "Unknown device type\n");
		return -EINVAL;
	}

	ret = rbtn_acquire(device, true);
	if (ret < 0) {
		dev_err(&device->dev, "Cannot enable device\n");
		return ret;
	}

	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
	if (!rbtn_data)
		return -ENOMEM;

	rbtn_data->type = type;
	device->driver_data = rbtn_data;

	switch (rbtn_data->type) {
	case RBTN_TOGGLE:
		ret = rbtn_input_init(rbtn_data);
		break;
	case RBTN_SLIDER:
		if (auto_remove_rfkill && rbtn_chain_head.head)
			ret = 0;
		else
			ret = rbtn_rfkill_init(device);
		break;
	default:
		ret = -EINVAL;
	}

	return ret;

}

static int rbtn_remove(struct acpi_device *device)
{
	struct rbtn_data *rbtn_data = device->driver_data;

	switch (rbtn_data->type) {
	case RBTN_TOGGLE:
		rbtn_input_exit(rbtn_data);
		break;
	case RBTN_SLIDER:
		rbtn_rfkill_exit(device);
		break;
	default:
		break;
	}

	rbtn_acquire(device, false);
	device->driver_data = NULL;

	return 0;
}

static void rbtn_notify(struct acpi_device *device, u32 event)
{
	struct rbtn_data *rbtn_data = device->driver_data;

	if (event != 0x80) {
		dev_info(&device->dev, "Received unknown event (0x%x)\n",
			 event);
		return;
	}

	switch (rbtn_data->type) {
	case RBTN_TOGGLE:
		rbtn_input_event(rbtn_data);
		break;
	case RBTN_SLIDER:
		rbtn_rfkill_event(device);
		atomic_notifier_call_chain(&rbtn_chain_head, event, device);
		break;
	default:
		break;
	}
}


/*
 * module functions
 */

module_acpi_driver(rbtn_driver);

module_param(auto_remove_rfkill, bool, 0444);

MODULE_PARM_DESC(auto_remove_rfkill, "Automatically remove rfkill devices when "
				     "other modules start receiving events "
				     "from this module and re-add them when "
				     "the last module stops receiving events "
				     "(default true)");
MODULE_DEVICE_TABLE(acpi, rbtn_ids);
MODULE_DESCRIPTION("Dell Airplane Mode Switch driver");
MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
817a5cdb PR	1	/*
	2	Dell Airplane Mode Switch driver
	3	Copyright (C) 2014-2015 Pali Rohár <pali.rohar@gmail.com>
	4
	5	This program is free software; you can redistribute it and/or modify
	6	it under the terms of the GNU General Public License as published by
	7	the Free Software Foundation; either version 2 of the License, or
	8	(at your option) any later version.
	9
	10	This program is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	GNU General Public License for more details.
	14	*/
	15
	16	#include <linux/module.h>
	17	#include <linux/acpi.h>
	18	#include <linux/rfkill.h>
	19	#include <linux/input.h>
	20
	21	enum rbtn_type {
	22	RBTN_UNKNOWN,
	23	RBTN_TOGGLE,
	24	RBTN_SLIDER,
	25	};
	26
	27	struct rbtn_data {
	28	enum rbtn_type type;
	29	struct rfkill *rfkill;
	30	struct input_dev *input_dev;
	31	};
	32
	33
	34	/*
	35	* acpi functions
	36	*/
	37
	38	static enum rbtn_type rbtn_check(struct acpi_device *device)
	39	{
	40	unsigned long long output;
	41	acpi_status status;
	42
	43	status = acpi_evaluate_integer(device->handle, "CRBT", NULL, &output);
	44	if (ACPI_FAILURE(status))
	45	return RBTN_UNKNOWN;
	46
	47	switch (output) {
	48	case 0:
	49	case 1:
	50	return RBTN_TOGGLE;
	51	case 2:
	52	case 3:
	53	return RBTN_SLIDER;
	54	default:
	55	return RBTN_UNKNOWN;
	56	}
	57	}
	58
	59	static int rbtn_get(struct acpi_device *device)
	60	{
	61	unsigned long long output;
	62	acpi_status status;
	63
	64	status = acpi_evaluate_integer(device->handle, "GRBT", NULL, &output);
65	if (ACPI_FAILURE(status))
66	return -EINVAL;
67
68	return !output;
69	}
70
71	static int rbtn_acquire(struct acpi_device *device, bool enable)
72	{
73	struct acpi_object_list input;
74	union acpi_object param;
75	acpi_status status;
76
77	param.type = ACPI_TYPE_INTEGER;
78	param.integer.value = enable;
79	input.count = 1;
80	input.pointer = &param;
81
82	status = acpi_evaluate_object(device->handle, "ARBT", &input, NULL);
83	if (ACPI_FAILURE(status))
84	return -EINVAL;
85
86	return 0;
87	}
88
89
90	/*
91	* rfkill device
92	*/
93
94	static void rbtn_rfkill_query(struct rfkill rfkill, void data)
95	{
96	struct acpi_device *device = data;
97	int state;
98
99	state = rbtn_get(device);
100	if (state < 0)
101	return;
102
103	rfkill_set_states(rfkill, state, state);
104	}
105
106	static int rbtn_rfkill_set_block(void *data, bool blocked)
107	{
108	/* NOTE: setting soft rfkill state is not supported */
109	return -EINVAL;
110	}
111
112	static struct rfkill_ops rbtn_ops = {
113	.query = rbtn_rfkill_query,
114	.set_block = rbtn_rfkill_set_block,
115	};
116
117	static int rbtn_rfkill_init(struct acpi_device *device)
118	{
119	struct rbtn_data *rbtn_data = device->driver_data;
120	int ret;
121
122	if (rbtn_data->rfkill)
123	return 0;
124
125	/*
126	* NOTE: rbtn controls all radio devices, not only WLAN
127	* but rfkill interface does not support "ANY" type
128	* so "WLAN" type is used
129	*/
130	rbtn_data->rfkill = rfkill_alloc("dell-rbtn", &device->dev,
131	RFKILL_TYPE_WLAN, &rbtn_ops, device);
132	if (!rbtn_data->rfkill)
133	return -ENOMEM;
134
135	ret = rfkill_register(rbtn_data->rfkill);
136	if (ret) {
137	rfkill_destroy(rbtn_data->rfkill);
138	rbtn_data->rfkill = NULL;
139	return ret;
140	}
141
142	return 0;
143	}
144
145	static void rbtn_rfkill_exit(struct acpi_device *device)
146	{
147	struct rbtn_data *rbtn_data = device->driver_data;
148
149	if (!rbtn_data->rfkill)
150	return;
151
152	rfkill_unregister(rbtn_data->rfkill);
153	rfkill_destroy(rbtn_data->rfkill);
154	rbtn_data->rfkill = NULL;
155	}
156
157	static void rbtn_rfkill_event(struct acpi_device *device)
158	{
159	struct rbtn_data *rbtn_data = device->driver_data;
160
161	if (rbtn_data->rfkill)
162	rbtn_rfkill_query(rbtn_data->rfkill, device);
163	}
164
165
166	/*
167	* input device
168	*/
169
170	static int rbtn_input_init(struct rbtn_data *rbtn_data)
171	{
172	int ret;
173
174	rbtn_data->input_dev = input_allocate_device();
175	if (!rbtn_data->input_dev)
176	return -ENOMEM;
177
178	rbtn_data->input_dev->name = "DELL Wireless hotkeys";
179	rbtn_data->input_dev->phys = "dellabce/input0";
180	rbtn_data->input_dev->id.bustype = BUS_HOST;
181	rbtn_data->input_dev->evbit[0] = BIT(EV_KEY);
182	set_bit(KEY_RFKILL, rbtn_data->input_dev->keybit);
183
184	ret = input_register_device(rbtn_data->input_dev);
185	if (ret) {
186	input_free_device(rbtn_data->input_dev);
187	rbtn_data->input_dev = NULL;
188	return ret;
189	}
190
191	return 0;
192	}
193
194	static void rbtn_input_exit(struct rbtn_data *rbtn_data)
195	{
196	input_unregister_device(rbtn_data->input_dev);
197	rbtn_data->input_dev = NULL;
198	}
199
200	static void rbtn_input_event(struct rbtn_data *rbtn_data)
201	{
202	input_report_key(rbtn_data->input_dev, KEY_RFKILL, 1);
203	input_sync(rbtn_data->input_dev);
204	input_report_key(rbtn_data->input_dev, KEY_RFKILL, 0);
205	input_sync(rbtn_data->input_dev);
206	}
207
208
209	/*
210	* acpi driver
211	*/
212
213	static int rbtn_add(struct acpi_device *device);
214	static int rbtn_remove(struct acpi_device *device);
215	static void rbtn_notify(struct acpi_device *device, u32 event);
216
217	static const struct acpi_device_id rbtn_ids[] = {
218	{ "DELRBTN", 0 },
219	{ "DELLABCE", 0 },
220	{ "", 0 },
221	};
222
223	static struct acpi_driver rbtn_driver = {
224	.name = "dell-rbtn",
225	.ids = rbtn_ids,
226	.ops = {
227	.add = rbtn_add,
228	.remove = rbtn_remove,
229	.notify = rbtn_notify,
230	},
231	.owner = THIS_MODULE,
232	};
233
234
b05ffc95 PR	235	/*
	236	* notifier export functions
	237	*/
	238
	239	static bool auto_remove_rfkill = true;
	240
	241	static ATOMIC_NOTIFIER_HEAD(rbtn_chain_head);
	242
	243	static int rbtn_inc_count(struct device dev, void data)
	244	{
	245	struct acpi_device *device = to_acpi_device(dev);
	246	struct rbtn_data *rbtn_data = device->driver_data;
	247	int *count = data;
	248
	249	if (rbtn_data->type == RBTN_SLIDER)
	250	(*count)++;
	251
	252	return 0;
	253	}
	254
	255	static int rbtn_switch_dev(struct device dev, void data)
	256	{
	257	struct acpi_device *device = to_acpi_device(dev);
	258	struct rbtn_data *rbtn_data = device->driver_data;
	259	bool enable = data;
	260
	261	if (rbtn_data->type != RBTN_SLIDER)
	262	return 0;
	263
	264	if (enable)
	265	rbtn_rfkill_init(device);
	266	else
	267	rbtn_rfkill_exit(device);
	268
	269	return 0;
	270	}
	271
	272	int dell_rbtn_notifier_register(struct notifier_block *nb)
	273	{
	274	bool first;
	275	int count;
	276	int ret;
	277
	278	count = 0;
	279	ret = driver_for_each_device(&rbtn_driver.drv, NULL, &count,
	280	rbtn_inc_count);
	281	if (ret \|\| count == 0)
	282	return -ENODEV;
	283
	284	first = !rbtn_chain_head.head;
	285
	286	ret = atomic_notifier_chain_register(&rbtn_chain_head, nb);
	287	if (ret != 0)
	288	return ret;
	289
	290	if (auto_remove_rfkill && first)
	291	ret = driver_for_each_device(&rbtn_driver.drv, NULL,
	292	(void *)false, rbtn_switch_dev);
	293
	294	return ret;
	295	}
	296	EXPORT_SYMBOL_GPL(dell_rbtn_notifier_register);
	297
	298	int dell_rbtn_notifier_unregister(struct notifier_block *nb)
299	{
300	int ret;
301
302	ret = atomic_notifier_chain_unregister(&rbtn_chain_head, nb);
303	if (ret != 0)
304	return ret;
305
306	if (auto_remove_rfkill && !rbtn_chain_head.head)
307	ret = driver_for_each_device(&rbtn_driver.drv, NULL,
308	(void *)true, rbtn_switch_dev);
309
310	return ret;
311	}
312	EXPORT_SYMBOL_GPL(dell_rbtn_notifier_unregister);
313
314
817a5cdb PR	315	/*
	316	* acpi driver functions
	317	*/
	318
	319	static int rbtn_add(struct acpi_device *device)
	320	{
	321	struct rbtn_data *rbtn_data;
	322	enum rbtn_type type;
	323	int ret = 0;
	324
	325	type = rbtn_check(device);
	326	if (type == RBTN_UNKNOWN) {
	327	dev_info(&device->dev, "Unknown device type\n");
	328	return -EINVAL;
	329	}
	330
	331	ret = rbtn_acquire(device, true);
	332	if (ret < 0) {
	333	dev_err(&device->dev, "Cannot enable device\n");
	334	return ret;
	335	}
	336
	337	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
	338	if (!rbtn_data)
	339	return -ENOMEM;
	340
	341	rbtn_data->type = type;
	342	device->driver_data = rbtn_data;
	343
	344	switch (rbtn_data->type) {
	345	case RBTN_TOGGLE:
	346	ret = rbtn_input_init(rbtn_data);
	347	break;
	348	case RBTN_SLIDER:
b05ffc95 PR	349	if (auto_remove_rfkill && rbtn_chain_head.head)
	350	ret = 0;
	351	else
	352	ret = rbtn_rfkill_init(device);
817a5cdb PR	353	break;
	354	default:
	355	ret = -EINVAL;
	356	}
	357
	358	return ret;
	359
	360	}
	361
	362	static int rbtn_remove(struct acpi_device *device)
	363	{
	364	struct rbtn_data *rbtn_data = device->driver_data;
	365
	366	switch (rbtn_data->type) {
	367	case RBTN_TOGGLE:
	368	rbtn_input_exit(rbtn_data);
	369	break;
	370	case RBTN_SLIDER:
	371	rbtn_rfkill_exit(device);
	372	break;
	373	default:
	374	break;
	375	}
	376
	377	rbtn_acquire(device, false);
	378	device->driver_data = NULL;
	379
	380	return 0;
	381	}
	382
	383	static void rbtn_notify(struct acpi_device *device, u32 event)
	384	{
	385	struct rbtn_data *rbtn_data = device->driver_data;
	386
	387	if (event != 0x80) {
	388	dev_info(&device->dev, "Received unknown event (0x%x)\n",
	389	event);
	390	return;
	391	}
	392
	393	switch (rbtn_data->type) {
	394	case RBTN_TOGGLE:
	395	rbtn_input_event(rbtn_data);
	396	break;
	397	case RBTN_SLIDER:
	398	rbtn_rfkill_event(device);
b05ffc95	399	atomic_notifier_call_chain(&rbtn_chain_head, event, device);
817a5cdb PR	400	break;
	401	default:
	402	break;
	403	}
	404	}
	405
	406
	407	/*
	408	* module functions
	409	*/
	410
	411	module_acpi_driver(rbtn_driver);
	412
b05ffc95 PR	413	module_param(auto_remove_rfkill, bool, 0444);
	414
	415	MODULE_PARM_DESC(auto_remove_rfkill, "Automatically remove rfkill devices when "
	416	"other modules start receiving events "
	417	"from this module and re-add them when "
	418	"the last module stops receiving events "
	419	"(default true)");
817a5cdb PR	420	MODULE_DEVICE_TABLE(acpi, rbtn_ids);
	421	MODULE_DESCRIPTION("Dell Airplane Mode Switch driver");
	422	MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
	423	MODULE_LICENSE("GPL");