toshiba_bluetooth.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Toshiba Bluetooth Enable Driver
  4 *
  5 * Copyright (C) 2009 Jes Sorensen <Jes.Sorensen@gmail.com>
  6 * Copyright (C) 2015 Azael Avalos <coproscefalo@gmail.com>
  7 *
  8 * Thanks to Matthew Garrett for background info on ACPI innards which
  9 * normal people aren't meant to understand :-)
 10 */
 11
 12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 13
 14#include <linux/kernel.h>
 15#include <linux/module.h>
 16#include <linux/init.h>
 17#include <linux/types.h>
 18#include <linux/acpi.h>
 19#include <linux/rfkill.h>
 20
 21#define BT_KILLSWITCH_MASK	0x01
 22#define BT_PLUGGED_MASK		0x40
 23#define BT_POWER_MASK		0x80
 24
 25MODULE_AUTHOR("Jes Sorensen <Jes.Sorensen@gmail.com>");
 26MODULE_DESCRIPTION("Toshiba Laptop ACPI Bluetooth Enable Driver");
 27MODULE_LICENSE("GPL");
 28
 29struct toshiba_bluetooth_dev {
 30	struct acpi_device *acpi_dev;
 31	struct rfkill *rfk;
 32
 33	bool killswitch;
 34	bool plugged;
 35	bool powered;
 36};
 37
 38static int toshiba_bt_rfkill_add(struct acpi_device *device);
 39static void toshiba_bt_rfkill_remove(struct acpi_device *device);
 40static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event);
 41
 42static const struct acpi_device_id bt_device_ids[] = {
 43	{ "TOS6205", 0},
 44	{ "", 0},
 45};
 46MODULE_DEVICE_TABLE(acpi, bt_device_ids);
 47
 48#ifdef CONFIG_PM_SLEEP
 49static int toshiba_bt_resume(struct device *dev);
 50#endif
 51static SIMPLE_DEV_PM_OPS(toshiba_bt_pm, NULL, toshiba_bt_resume);
 52
 53static struct acpi_driver toshiba_bt_rfkill_driver = {
 54	.name =		"Toshiba BT",
 55	.class =	"Toshiba",
 56	.ids =		bt_device_ids,
 57	.ops =		{
 58				.add =		toshiba_bt_rfkill_add,
 59				.remove =	toshiba_bt_rfkill_remove,
 60				.notify =	toshiba_bt_rfkill_notify,
 61			},
 62	.drv.pm =	&toshiba_bt_pm,
 63};
 64
 65static int toshiba_bluetooth_present(acpi_handle handle)
 66{
 67	acpi_status result;
 68	u64 bt_present;
 69
 70	/*
 71	 * Some Toshiba laptops may have a fake TOS6205 device in
 72	 * their ACPI BIOS, so query the _STA method to see if there
 73	 * is really anything there.
 74	 */
 75	result = acpi_evaluate_integer(handle, "_STA", NULL, &bt_present);
 76	if (ACPI_FAILURE(result)) {
 77		pr_err("ACPI call to query Bluetooth presence failed\n");
 78		return -ENXIO;
 79	}
 80
 81	if (!bt_present) {
 82		pr_info("Bluetooth device not present\n");
 83		return -ENODEV;
 84	}
 85
 86	return 0;
 87}
 88
 89static int toshiba_bluetooth_status(acpi_handle handle)
 90{
 91	acpi_status result;
 92	u64 status;
 93
 94	result = acpi_evaluate_integer(handle, "BTST", NULL, &status);
 95	if (ACPI_FAILURE(result)) {
 96		pr_err("Could not get Bluetooth device status\n");
 97		return -ENXIO;
 98	}
 99
100	return status;
101}
102
103static int toshiba_bluetooth_enable(acpi_handle handle)
104{
105	acpi_status result;
106
107	result = acpi_evaluate_object(handle, "AUSB", NULL, NULL);
108	if (ACPI_FAILURE(result)) {
109		pr_err("Could not attach USB Bluetooth device\n");
110		return -ENXIO;
111	}
112
113	result = acpi_evaluate_object(handle, "BTPO", NULL, NULL);
114	if (ACPI_FAILURE(result)) {
115		pr_err("Could not power ON Bluetooth device\n");
116		return -ENXIO;
117	}
118
119	return 0;
120}
121
122static int toshiba_bluetooth_disable(acpi_handle handle)
123{
124	acpi_status result;
125
126	result = acpi_evaluate_object(handle, "BTPF", NULL, NULL);
127	if (ACPI_FAILURE(result)) {
128		pr_err("Could not power OFF Bluetooth device\n");
129		return -ENXIO;
130	}
131
132	result = acpi_evaluate_object(handle, "DUSB", NULL, NULL);
133	if (ACPI_FAILURE(result)) {
134		pr_err("Could not detach USB Bluetooth device\n");
135		return -ENXIO;
136	}
137
138	return 0;
139}
140
141/* Helper function */
142static int toshiba_bluetooth_sync_status(struct toshiba_bluetooth_dev *bt_dev)
143{
144	int status;
145
146	status = toshiba_bluetooth_status(bt_dev->acpi_dev->handle);
147	if (status < 0) {
148		pr_err("Could not sync bluetooth device status\n");
149		return status;
150	}
151
152	bt_dev->killswitch = (status & BT_KILLSWITCH_MASK) ? true : false;
153	bt_dev->plugged = (status & BT_PLUGGED_MASK) ? true : false;
154	bt_dev->powered = (status & BT_POWER_MASK) ? true : false;
155
156	pr_debug("Bluetooth status %d killswitch %d plugged %d powered %d\n",
157		 status, bt_dev->killswitch, bt_dev->plugged, bt_dev->powered);
158
159	return 0;
160}
161
162/* RFKill handlers */
163static int bt_rfkill_set_block(void *data, bool blocked)
164{
165	struct toshiba_bluetooth_dev *bt_dev = data;
166	int ret;
167
168	ret = toshiba_bluetooth_sync_status(bt_dev);
169	if (ret)
170		return ret;
171
172	if (!bt_dev->killswitch)
173		return 0;
174
175	if (blocked)
176		ret = toshiba_bluetooth_disable(bt_dev->acpi_dev->handle);
177	else
178		ret = toshiba_bluetooth_enable(bt_dev->acpi_dev->handle);
179
180	return ret;
181}
182
183static void bt_rfkill_poll(struct rfkill *rfkill, void *data)
184{
185	struct toshiba_bluetooth_dev *bt_dev = data;
186
187	if (toshiba_bluetooth_sync_status(bt_dev))
188		return;
189
190	/*
191	 * Note the Toshiba Bluetooth RFKill switch seems to be a strange
192	 * fish. It only provides a BT event when the switch is flipped to
193	 * the 'on' position. When flipping it to 'off', the USB device is
194	 * simply pulled away underneath us, without any BT event being
195	 * delivered.
196	 */
197	rfkill_set_hw_state(bt_dev->rfk, !bt_dev->killswitch);
198}
199
200static const struct rfkill_ops rfk_ops = {
201	.set_block = bt_rfkill_set_block,
202	.poll = bt_rfkill_poll,
203};
204
205/* ACPI driver functions */
206static void toshiba_bt_rfkill_notify(struct acpi_device *device, u32 event)
207{
208	struct toshiba_bluetooth_dev *bt_dev = acpi_driver_data(device);
209
210	if (toshiba_bluetooth_sync_status(bt_dev))
211		return;
212
213	rfkill_set_hw_state(bt_dev->rfk, !bt_dev->killswitch);
214}
215
216#ifdef CONFIG_PM_SLEEP
217static int toshiba_bt_resume(struct device *dev)
218{
219	struct toshiba_bluetooth_dev *bt_dev;
220	int ret;
221
222	bt_dev = acpi_driver_data(to_acpi_device(dev));
223
224	ret = toshiba_bluetooth_sync_status(bt_dev);
225	if (ret)
226		return ret;
227
228	rfkill_set_hw_state(bt_dev->rfk, !bt_dev->killswitch);
229
230	return 0;
231}
232#endif
233
234static int toshiba_bt_rfkill_add(struct acpi_device *device)
235{
236	struct toshiba_bluetooth_dev *bt_dev;
237	int result;
238
239	result = toshiba_bluetooth_present(device->handle);
240	if (result)
241		return result;
242
243	pr_info("Toshiba ACPI Bluetooth device driver\n");
244
245	bt_dev = kzalloc(sizeof(*bt_dev), GFP_KERNEL);
246	if (!bt_dev)
247		return -ENOMEM;
248	bt_dev->acpi_dev = device;
249	device->driver_data = bt_dev;
250	dev_set_drvdata(&device->dev, bt_dev);
251
252	result = toshiba_bluetooth_sync_status(bt_dev);
253	if (result) {
254		kfree(bt_dev);
255		return result;
256	}
257
258	bt_dev->rfk = rfkill_alloc("Toshiba Bluetooth",
259				   &device->dev,
260				   RFKILL_TYPE_BLUETOOTH,
261				   &rfk_ops,
262				   bt_dev);
263	if (!bt_dev->rfk) {
264		pr_err("Unable to allocate rfkill device\n");
265		kfree(bt_dev);
266		return -ENOMEM;
267	}
268
269	rfkill_set_hw_state(bt_dev->rfk, !bt_dev->killswitch);
270
271	result = rfkill_register(bt_dev->rfk);
272	if (result) {
273		pr_err("Unable to register rfkill device\n");
274		rfkill_destroy(bt_dev->rfk);
275		kfree(bt_dev);
276	}
277
278	return result;
279}
280
281static void toshiba_bt_rfkill_remove(struct acpi_device *device)
282{
283	struct toshiba_bluetooth_dev *bt_dev = acpi_driver_data(device);
284
285	/* clean up */
286	if (bt_dev->rfk) {
287		rfkill_unregister(bt_dev->rfk);
288		rfkill_destroy(bt_dev->rfk);
289	}
290
291	kfree(bt_dev);
292
293	toshiba_bluetooth_disable(device->handle);
294}
295
296module_acpi_driver(toshiba_bt_rfkill_driver);