xref: /linux/drivers/platform/x86/intel/oaktrail.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Intel OakTrail Platform support
4  *
5  * Copyright (C) 2010-2011 Intel Corporation
6  * Author: Yin Kangkai (kangkai.yin@intel.com)
7  *
8  * based on Compal driver, Copyright (C) 2008 Cezary Jackiewicz
9  * <cezary.jackiewicz (at) gmail.com>, based on MSI driver
10  * Copyright (C) 2006 Lennart Poettering <mzxreary (at) 0pointer (dot) de>
11  *
12  * This driver does below things:
13  * 1. registers itself in the Linux backlight control in
14  *    /sys/class/backlight/intel_oaktrail/
15  *
16  * 2. registers in the rfkill subsystem here: /sys/class/rfkill/rfkillX/
17  *    for these components: wifi, bluetooth, wwan (3g), gps
18  *
19  * This driver might work on other products based on Oaktrail. If you
20  * want to try it you can pass force=1 as argument to the module which
21  * will force it to load even when the DMI data doesn't identify the
22  * product as compatible.
23  */
24 
25 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
26 
27 #include <linux/acpi.h>
28 #include <linux/backlight.h>
29 #include <linux/dmi.h>
30 #include <linux/err.h>
31 #include <linux/i2c.h>
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/mutex.h>
35 #include <linux/platform_device.h>
36 #include <linux/rfkill.h>
37 
38 #include <acpi/video.h>
39 
40 #define DRIVER_NAME	"intel_oaktrail"
41 #define DRIVER_VERSION	"0.4ac1"
42 
43 /*
44  * This is the devices status address in EC space, and the control bits
45  * definition:
46  *
47  * (1 << 0):	Camera enable/disable, RW.
48  * (1 << 1):	Bluetooth enable/disable, RW.
49  * (1 << 2):	GPS enable/disable, RW.
50  * (1 << 3):	WiFi enable/disable, RW.
51  * (1 << 4):	WWAN (3G) enable/disable, RW.
52  * (1 << 5):	Touchscreen enable/disable, Read Only.
53  */
54 #define OT_EC_DEVICE_STATE_ADDRESS	0xD6
55 
56 #define OT_EC_CAMERA_MASK	(1 << 0)
57 #define OT_EC_BT_MASK		(1 << 1)
58 #define OT_EC_GPS_MASK		(1 << 2)
59 #define OT_EC_WIFI_MASK		(1 << 3)
60 #define OT_EC_WWAN_MASK		(1 << 4)
61 #define OT_EC_TS_MASK		(1 << 5)
62 
63 /*
64  * This is the address in EC space and commands used to control LCD backlight:
65  *
66  * Two steps needed to change the LCD backlight:
67  *   1. write the backlight percentage into OT_EC_BL_BRIGHTNESS_ADDRESS;
68  *   2. write OT_EC_BL_CONTROL_ON_DATA into OT_EC_BL_CONTROL_ADDRESS.
69  *
70  * To read the LCD back light, just read out the value from
71  * OT_EC_BL_BRIGHTNESS_ADDRESS.
72  *
73  * LCD backlight brightness range: 0 - 100 (OT_EC_BL_BRIGHTNESS_MAX)
74  */
75 #define OT_EC_BL_BRIGHTNESS_ADDRESS	0x44
76 #define OT_EC_BL_BRIGHTNESS_MAX		100
77 #define OT_EC_BL_CONTROL_ADDRESS	0x3A
78 #define OT_EC_BL_CONTROL_ON_DATA	0x1A
79 
80 
81 static bool force;
82 module_param(force, bool, 0);
83 MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
84 
85 static struct platform_device *oaktrail_device;
86 static struct backlight_device *oaktrail_bl_device;
87 static struct rfkill *bt_rfkill;
88 static struct rfkill *gps_rfkill;
89 static struct rfkill *wifi_rfkill;
90 static struct rfkill *wwan_rfkill;
91 
92 
93 /* rfkill */
94 static int oaktrail_rfkill_set(void *data, bool blocked)
95 {
96 	u8 value;
97 	u8 result;
98 	unsigned long radio = (unsigned long) data;
99 
100 	ec_read(OT_EC_DEVICE_STATE_ADDRESS, &result);
101 
102 	if (!blocked)
103 		value = (u8) (result | radio);
104 	else
105 		value = (u8) (result & ~radio);
106 
107 	ec_write(OT_EC_DEVICE_STATE_ADDRESS, value);
108 
109 	return 0;
110 }
111 
112 static const struct rfkill_ops oaktrail_rfkill_ops = {
113 	.set_block = oaktrail_rfkill_set,
114 };
115 
116 static struct rfkill *oaktrail_rfkill_new(char *name, enum rfkill_type type,
117 					  unsigned long mask)
118 {
119 	struct rfkill *rfkill_dev;
120 	u8 value;
121 	int err;
122 
123 	rfkill_dev = rfkill_alloc(name, &oaktrail_device->dev, type,
124 				  &oaktrail_rfkill_ops, (void *)mask);
125 	if (!rfkill_dev)
126 		return ERR_PTR(-ENOMEM);
127 
128 	ec_read(OT_EC_DEVICE_STATE_ADDRESS, &value);
129 	rfkill_init_sw_state(rfkill_dev, (value & mask) != 1);
130 
131 	err = rfkill_register(rfkill_dev);
132 	if (err) {
133 		rfkill_destroy(rfkill_dev);
134 		return ERR_PTR(err);
135 	}
136 
137 	return rfkill_dev;
138 }
139 
140 static inline void __oaktrail_rfkill_cleanup(struct rfkill *rf)
141 {
142 	if (rf) {
143 		rfkill_unregister(rf);
144 		rfkill_destroy(rf);
145 	}
146 }
147 
148 static void oaktrail_rfkill_cleanup(void)
149 {
150 	__oaktrail_rfkill_cleanup(wifi_rfkill);
151 	__oaktrail_rfkill_cleanup(bt_rfkill);
152 	__oaktrail_rfkill_cleanup(gps_rfkill);
153 	__oaktrail_rfkill_cleanup(wwan_rfkill);
154 }
155 
156 static int oaktrail_rfkill_init(void)
157 {
158 	int ret;
159 
160 	wifi_rfkill = oaktrail_rfkill_new("oaktrail-wifi",
161 					  RFKILL_TYPE_WLAN,
162 					  OT_EC_WIFI_MASK);
163 	if (IS_ERR(wifi_rfkill)) {
164 		ret = PTR_ERR(wifi_rfkill);
165 		wifi_rfkill = NULL;
166 		goto cleanup;
167 	}
168 
169 	bt_rfkill = oaktrail_rfkill_new("oaktrail-bluetooth",
170 					RFKILL_TYPE_BLUETOOTH,
171 					OT_EC_BT_MASK);
172 	if (IS_ERR(bt_rfkill)) {
173 		ret = PTR_ERR(bt_rfkill);
174 		bt_rfkill = NULL;
175 		goto cleanup;
176 	}
177 
178 	gps_rfkill = oaktrail_rfkill_new("oaktrail-gps",
179 					 RFKILL_TYPE_GPS,
180 					 OT_EC_GPS_MASK);
181 	if (IS_ERR(gps_rfkill)) {
182 		ret = PTR_ERR(gps_rfkill);
183 		gps_rfkill = NULL;
184 		goto cleanup;
185 	}
186 
187 	wwan_rfkill = oaktrail_rfkill_new("oaktrail-wwan",
188 					  RFKILL_TYPE_WWAN,
189 					  OT_EC_WWAN_MASK);
190 	if (IS_ERR(wwan_rfkill)) {
191 		ret = PTR_ERR(wwan_rfkill);
192 		wwan_rfkill = NULL;
193 		goto cleanup;
194 	}
195 
196 	return 0;
197 
198 cleanup:
199 	oaktrail_rfkill_cleanup();
200 	return ret;
201 }
202 
203 
204 /* backlight */
205 static int get_backlight_brightness(struct backlight_device *b)
206 {
207 	u8 value;
208 	ec_read(OT_EC_BL_BRIGHTNESS_ADDRESS, &value);
209 
210 	return value;
211 }
212 
213 static int set_backlight_brightness(struct backlight_device *b)
214 {
215 	u8 percent = (u8) b->props.brightness;
216 	if (percent < 0 || percent > OT_EC_BL_BRIGHTNESS_MAX)
217 		return -EINVAL;
218 
219 	ec_write(OT_EC_BL_BRIGHTNESS_ADDRESS, percent);
220 	ec_write(OT_EC_BL_CONTROL_ADDRESS, OT_EC_BL_CONTROL_ON_DATA);
221 
222 	return 0;
223 }
224 
225 static const struct backlight_ops oaktrail_bl_ops = {
226 	.get_brightness = get_backlight_brightness,
227 	.update_status	= set_backlight_brightness,
228 };
229 
230 static int oaktrail_backlight_init(void)
231 {
232 	struct backlight_device *bd;
233 	struct backlight_properties props;
234 
235 	memset(&props, 0, sizeof(struct backlight_properties));
236 	props.type = BACKLIGHT_PLATFORM;
237 	props.max_brightness = OT_EC_BL_BRIGHTNESS_MAX;
238 	bd = backlight_device_register(DRIVER_NAME,
239 				       &oaktrail_device->dev, NULL,
240 				       &oaktrail_bl_ops,
241 				       &props);
242 
243 	if (IS_ERR(bd)) {
244 		oaktrail_bl_device = NULL;
245 		pr_warn("Unable to register backlight device\n");
246 		return PTR_ERR(bd);
247 	}
248 
249 	oaktrail_bl_device = bd;
250 
251 	bd->props.brightness = get_backlight_brightness(bd);
252 	bd->props.power = BACKLIGHT_POWER_ON;
253 	backlight_update_status(bd);
254 
255 	return 0;
256 }
257 
258 static void oaktrail_backlight_exit(void)
259 {
260 	backlight_device_unregister(oaktrail_bl_device);
261 }
262 
263 static int oaktrail_probe(struct platform_device *pdev)
264 {
265 	return 0;
266 }
267 
268 static struct platform_driver oaktrail_driver = {
269 	.driver = {
270 		.name = DRIVER_NAME,
271 	},
272 	.probe	= oaktrail_probe,
273 };
274 
275 static int dmi_check_cb(const struct dmi_system_id *id)
276 {
277 	pr_info("Identified model '%s'\n", id->ident);
278 	return 0;
279 }
280 
281 static const struct dmi_system_id oaktrail_dmi_table[] __initconst = {
282 	{
283 		.ident = "OakTrail platform",
284 		.matches = {
285 			DMI_MATCH(DMI_PRODUCT_NAME, "OakTrail platform"),
286 		},
287 		.callback = dmi_check_cb
288 	},
289 	{ }
290 };
291 MODULE_DEVICE_TABLE(dmi, oaktrail_dmi_table);
292 
293 static int __init oaktrail_init(void)
294 {
295 	int ret;
296 
297 	if (acpi_disabled) {
298 		pr_err("ACPI needs to be enabled for this driver to work!\n");
299 		return -ENODEV;
300 	}
301 
302 	if (!force && !dmi_check_system(oaktrail_dmi_table)) {
303 		pr_err("Platform not recognized (You could try the module's force-parameter)");
304 		return -ENODEV;
305 	}
306 
307 	ret = platform_driver_register(&oaktrail_driver);
308 	if (ret) {
309 		pr_warn("Unable to register platform driver\n");
310 		goto err_driver_reg;
311 	}
312 
313 	oaktrail_device = platform_device_alloc(DRIVER_NAME, PLATFORM_DEVID_NONE);
314 	if (!oaktrail_device) {
315 		pr_warn("Unable to allocate platform device\n");
316 		ret = -ENOMEM;
317 		goto err_device_alloc;
318 	}
319 
320 	ret = platform_device_add(oaktrail_device);
321 	if (ret) {
322 		pr_warn("Unable to add platform device\n");
323 		goto err_device_add;
324 	}
325 
326 	if (acpi_video_get_backlight_type() == acpi_backlight_vendor) {
327 		ret = oaktrail_backlight_init();
328 		if (ret)
329 			goto err_backlight;
330 	}
331 
332 	ret = oaktrail_rfkill_init();
333 	if (ret) {
334 		pr_warn("Setup rfkill failed\n");
335 		goto err_rfkill;
336 	}
337 
338 	pr_info("Driver "DRIVER_VERSION" successfully loaded\n");
339 	return 0;
340 
341 err_rfkill:
342 	oaktrail_backlight_exit();
343 err_backlight:
344 	platform_device_del(oaktrail_device);
345 err_device_add:
346 	platform_device_put(oaktrail_device);
347 err_device_alloc:
348 	platform_driver_unregister(&oaktrail_driver);
349 err_driver_reg:
350 
351 	return ret;
352 }
353 
354 static void __exit oaktrail_cleanup(void)
355 {
356 	oaktrail_backlight_exit();
357 	oaktrail_rfkill_cleanup();
358 	platform_device_unregister(oaktrail_device);
359 	platform_driver_unregister(&oaktrail_driver);
360 
361 	pr_info("Driver unloaded\n");
362 }
363 
364 module_init(oaktrail_init);
365 module_exit(oaktrail_cleanup);
366 
367 MODULE_AUTHOR("Yin Kangkai <kangkai.yin@intel.com>");
368 MODULE_DESCRIPTION("Intel Oaktrail Platform ACPI Extras");
369 MODULE_VERSION(DRIVER_VERSION);
370 MODULE_LICENSE("GPL");
371