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/fb.h>
32 #include <linux/i2c.h>
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/mutex.h>
36 #include <linux/platform_device.h>
37 #include <linux/rfkill.h>
38
39 #include <acpi/video.h>
40
41 #define DRIVER_NAME "intel_oaktrail"
42 #define DRIVER_VERSION "0.4ac1"
43
44 /*
45 * This is the devices status address in EC space, and the control bits
46 * definition:
47 *
48 * (1 << 0): Camera enable/disable, RW.
49 * (1 << 1): Bluetooth enable/disable, RW.
50 * (1 << 2): GPS enable/disable, RW.
51 * (1 << 3): WiFi enable/disable, RW.
52 * (1 << 4): WWAN (3G) enable/disable, RW.
53 * (1 << 5): Touchscreen enable/disable, Read Only.
54 */
55 #define OT_EC_DEVICE_STATE_ADDRESS 0xD6
56
57 #define OT_EC_CAMERA_MASK (1 << 0)
58 #define OT_EC_BT_MASK (1 << 1)
59 #define OT_EC_GPS_MASK (1 << 2)
60 #define OT_EC_WIFI_MASK (1 << 3)
61 #define OT_EC_WWAN_MASK (1 << 4)
62 #define OT_EC_TS_MASK (1 << 5)
63
64 /*
65 * This is the address in EC space and commands used to control LCD backlight:
66 *
67 * Two steps needed to change the LCD backlight:
68 * 1. write the backlight percentage into OT_EC_BL_BRIGHTNESS_ADDRESS;
69 * 2. write OT_EC_BL_CONTROL_ON_DATA into OT_EC_BL_CONTROL_ADDRESS.
70 *
71 * To read the LCD back light, just read out the value from
72 * OT_EC_BL_BRIGHTNESS_ADDRESS.
73 *
74 * LCD backlight brightness range: 0 - 100 (OT_EC_BL_BRIGHTNESS_MAX)
75 */
76 #define OT_EC_BL_BRIGHTNESS_ADDRESS 0x44
77 #define OT_EC_BL_BRIGHTNESS_MAX 100
78 #define OT_EC_BL_CONTROL_ADDRESS 0x3A
79 #define OT_EC_BL_CONTROL_ON_DATA 0x1A
80
81
82 static bool force;
83 module_param(force, bool, 0);
84 MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
85
86 static struct platform_device *oaktrail_device;
87 static struct backlight_device *oaktrail_bl_device;
88 static struct rfkill *bt_rfkill;
89 static struct rfkill *gps_rfkill;
90 static struct rfkill *wifi_rfkill;
91 static struct rfkill *wwan_rfkill;
92
93
94 /* rfkill */
oaktrail_rfkill_set(void * data,bool blocked)95 static int oaktrail_rfkill_set(void *data, bool blocked)
96 {
97 u8 value;
98 u8 result;
99 unsigned long radio = (unsigned long) data;
100
101 ec_read(OT_EC_DEVICE_STATE_ADDRESS, &result);
102
103 if (!blocked)
104 value = (u8) (result | radio);
105 else
106 value = (u8) (result & ~radio);
107
108 ec_write(OT_EC_DEVICE_STATE_ADDRESS, value);
109
110 return 0;
111 }
112
113 static const struct rfkill_ops oaktrail_rfkill_ops = {
114 .set_block = oaktrail_rfkill_set,
115 };
116
oaktrail_rfkill_new(char * name,enum rfkill_type type,unsigned long mask)117 static struct rfkill *oaktrail_rfkill_new(char *name, enum rfkill_type type,
118 unsigned long mask)
119 {
120 struct rfkill *rfkill_dev;
121 u8 value;
122 int err;
123
124 rfkill_dev = rfkill_alloc(name, &oaktrail_device->dev, type,
125 &oaktrail_rfkill_ops, (void *)mask);
126 if (!rfkill_dev)
127 return ERR_PTR(-ENOMEM);
128
129 ec_read(OT_EC_DEVICE_STATE_ADDRESS, &value);
130 rfkill_init_sw_state(rfkill_dev, (value & mask) != 1);
131
132 err = rfkill_register(rfkill_dev);
133 if (err) {
134 rfkill_destroy(rfkill_dev);
135 return ERR_PTR(err);
136 }
137
138 return rfkill_dev;
139 }
140
__oaktrail_rfkill_cleanup(struct rfkill * rf)141 static inline void __oaktrail_rfkill_cleanup(struct rfkill *rf)
142 {
143 if (rf) {
144 rfkill_unregister(rf);
145 rfkill_destroy(rf);
146 }
147 }
148
oaktrail_rfkill_cleanup(void)149 static void oaktrail_rfkill_cleanup(void)
150 {
151 __oaktrail_rfkill_cleanup(wifi_rfkill);
152 __oaktrail_rfkill_cleanup(bt_rfkill);
153 __oaktrail_rfkill_cleanup(gps_rfkill);
154 __oaktrail_rfkill_cleanup(wwan_rfkill);
155 }
156
oaktrail_rfkill_init(void)157 static int oaktrail_rfkill_init(void)
158 {
159 int ret;
160
161 wifi_rfkill = oaktrail_rfkill_new("oaktrail-wifi",
162 RFKILL_TYPE_WLAN,
163 OT_EC_WIFI_MASK);
164 if (IS_ERR(wifi_rfkill)) {
165 ret = PTR_ERR(wifi_rfkill);
166 wifi_rfkill = NULL;
167 goto cleanup;
168 }
169
170 bt_rfkill = oaktrail_rfkill_new("oaktrail-bluetooth",
171 RFKILL_TYPE_BLUETOOTH,
172 OT_EC_BT_MASK);
173 if (IS_ERR(bt_rfkill)) {
174 ret = PTR_ERR(bt_rfkill);
175 bt_rfkill = NULL;
176 goto cleanup;
177 }
178
179 gps_rfkill = oaktrail_rfkill_new("oaktrail-gps",
180 RFKILL_TYPE_GPS,
181 OT_EC_GPS_MASK);
182 if (IS_ERR(gps_rfkill)) {
183 ret = PTR_ERR(gps_rfkill);
184 gps_rfkill = NULL;
185 goto cleanup;
186 }
187
188 wwan_rfkill = oaktrail_rfkill_new("oaktrail-wwan",
189 RFKILL_TYPE_WWAN,
190 OT_EC_WWAN_MASK);
191 if (IS_ERR(wwan_rfkill)) {
192 ret = PTR_ERR(wwan_rfkill);
193 wwan_rfkill = NULL;
194 goto cleanup;
195 }
196
197 return 0;
198
199 cleanup:
200 oaktrail_rfkill_cleanup();
201 return ret;
202 }
203
204
205 /* backlight */
get_backlight_brightness(struct backlight_device * b)206 static int get_backlight_brightness(struct backlight_device *b)
207 {
208 u8 value;
209 ec_read(OT_EC_BL_BRIGHTNESS_ADDRESS, &value);
210
211 return value;
212 }
213
set_backlight_brightness(struct backlight_device * b)214 static int set_backlight_brightness(struct backlight_device *b)
215 {
216 u8 percent = (u8) b->props.brightness;
217 if (percent < 0 || percent > OT_EC_BL_BRIGHTNESS_MAX)
218 return -EINVAL;
219
220 ec_write(OT_EC_BL_BRIGHTNESS_ADDRESS, percent);
221 ec_write(OT_EC_BL_CONTROL_ADDRESS, OT_EC_BL_CONTROL_ON_DATA);
222
223 return 0;
224 }
225
226 static const struct backlight_ops oaktrail_bl_ops = {
227 .get_brightness = get_backlight_brightness,
228 .update_status = set_backlight_brightness,
229 };
230
oaktrail_backlight_init(void)231 static int oaktrail_backlight_init(void)
232 {
233 struct backlight_device *bd;
234 struct backlight_properties props;
235
236 memset(&props, 0, sizeof(struct backlight_properties));
237 props.type = BACKLIGHT_PLATFORM;
238 props.max_brightness = OT_EC_BL_BRIGHTNESS_MAX;
239 bd = backlight_device_register(DRIVER_NAME,
240 &oaktrail_device->dev, NULL,
241 &oaktrail_bl_ops,
242 &props);
243
244 if (IS_ERR(bd)) {
245 oaktrail_bl_device = NULL;
246 pr_warn("Unable to register backlight device\n");
247 return PTR_ERR(bd);
248 }
249
250 oaktrail_bl_device = bd;
251
252 bd->props.brightness = get_backlight_brightness(bd);
253 bd->props.power = FB_BLANK_UNBLANK;
254 backlight_update_status(bd);
255
256 return 0;
257 }
258
oaktrail_backlight_exit(void)259 static void oaktrail_backlight_exit(void)
260 {
261 backlight_device_unregister(oaktrail_bl_device);
262 }
263
oaktrail_probe(struct platform_device * pdev)264 static int oaktrail_probe(struct platform_device *pdev)
265 {
266 return 0;
267 }
268
oaktrail_remove(struct platform_device * pdev)269 static int oaktrail_remove(struct platform_device *pdev)
270 {
271 return 0;
272 }
273
274 static struct platform_driver oaktrail_driver = {
275 .driver = {
276 .name = DRIVER_NAME,
277 },
278 .probe = oaktrail_probe,
279 .remove = oaktrail_remove,
280 };
281
dmi_check_cb(const struct dmi_system_id * id)282 static int dmi_check_cb(const struct dmi_system_id *id)
283 {
284 pr_info("Identified model '%s'\n", id->ident);
285 return 0;
286 }
287
288 static const struct dmi_system_id oaktrail_dmi_table[] __initconst = {
289 {
290 .ident = "OakTrail platform",
291 .matches = {
292 DMI_MATCH(DMI_PRODUCT_NAME, "OakTrail platform"),
293 },
294 .callback = dmi_check_cb
295 },
296 { }
297 };
298 MODULE_DEVICE_TABLE(dmi, oaktrail_dmi_table);
299
oaktrail_init(void)300 static int __init oaktrail_init(void)
301 {
302 int ret;
303
304 if (acpi_disabled) {
305 pr_err("ACPI needs to be enabled for this driver to work!\n");
306 return -ENODEV;
307 }
308
309 if (!force && !dmi_check_system(oaktrail_dmi_table)) {
310 pr_err("Platform not recognized (You could try the module's force-parameter)");
311 return -ENODEV;
312 }
313
314 ret = platform_driver_register(&oaktrail_driver);
315 if (ret) {
316 pr_warn("Unable to register platform driver\n");
317 goto err_driver_reg;
318 }
319
320 oaktrail_device = platform_device_alloc(DRIVER_NAME, -1);
321 if (!oaktrail_device) {
322 pr_warn("Unable to allocate platform device\n");
323 ret = -ENOMEM;
324 goto err_device_alloc;
325 }
326
327 ret = platform_device_add(oaktrail_device);
328 if (ret) {
329 pr_warn("Unable to add platform device\n");
330 goto err_device_add;
331 }
332
333 if (acpi_video_get_backlight_type() == acpi_backlight_vendor) {
334 ret = oaktrail_backlight_init();
335 if (ret)
336 goto err_backlight;
337 }
338
339 ret = oaktrail_rfkill_init();
340 if (ret) {
341 pr_warn("Setup rfkill failed\n");
342 goto err_rfkill;
343 }
344
345 pr_info("Driver "DRIVER_VERSION" successfully loaded\n");
346 return 0;
347
348 err_rfkill:
349 oaktrail_backlight_exit();
350 err_backlight:
351 platform_device_del(oaktrail_device);
352 err_device_add:
353 platform_device_put(oaktrail_device);
354 err_device_alloc:
355 platform_driver_unregister(&oaktrail_driver);
356 err_driver_reg:
357
358 return ret;
359 }
360
oaktrail_cleanup(void)361 static void __exit oaktrail_cleanup(void)
362 {
363 oaktrail_backlight_exit();
364 oaktrail_rfkill_cleanup();
365 platform_device_unregister(oaktrail_device);
366 platform_driver_unregister(&oaktrail_driver);
367
368 pr_info("Driver unloaded\n");
369 }
370
371 module_init(oaktrail_init);
372 module_exit(oaktrail_cleanup);
373
374 MODULE_AUTHOR("Yin Kangkai (kangkai.yin@intel.com)");
375 MODULE_DESCRIPTION("Intel Oaktrail Platform ACPI Extras");
376 MODULE_VERSION(DRIVER_VERSION);
377 MODULE_LICENSE("GPL");
378