1 /*
2 * dell_led.c - Dell LED Driver
3 *
4 * Copyright (C) 2010 Dell Inc.
5 * Louis Davis <louis_davis@dell.com>
6 * Jim Dailey <jim_dailey@dell.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation.
11 *
12 */
13
14 #include <linux/acpi.h>
15 #include <linux/leds.h>
16 #include <linux/slab.h>
17 #include <linux/module.h>
18 #include <linux/dmi.h>
19 #include <linux/dell-led.h>
20
21 MODULE_AUTHOR("Louis Davis/Jim Dailey");
22 MODULE_DESCRIPTION("Dell LED Control Driver");
23 MODULE_LICENSE("GPL");
24
25 #define DELL_LED_BIOS_GUID "F6E4FE6E-909D-47cb-8BAB-C9F6F2F8D396"
26 #define DELL_APP_GUID "A80593CE-A997-11DA-B012-B622A1EF5492"
27 MODULE_ALIAS("wmi:" DELL_LED_BIOS_GUID);
28
29 /* Error Result Codes: */
30 #define INVALID_DEVICE_ID 250
31 #define INVALID_PARAMETER 251
32 #define INVALID_BUFFER 252
33 #define INTERFACE_ERROR 253
34 #define UNSUPPORTED_COMMAND 254
35 #define UNSPECIFIED_ERROR 255
36
37 /* Device ID */
38 #define DEVICE_ID_PANEL_BACK 1
39
40 /* LED Commands */
41 #define CMD_LED_ON 16
42 #define CMD_LED_OFF 17
43 #define CMD_LED_BLINK 18
44
45 struct app_wmi_args {
46 u16 class;
47 u16 selector;
48 u32 arg1;
49 u32 arg2;
50 u32 arg3;
51 u32 arg4;
52 u32 res1;
53 u32 res2;
54 u32 res3;
55 u32 res4;
56 char dummy[92];
57 };
58
59 #define GLOBAL_MIC_MUTE_ENABLE 0x364
60 #define GLOBAL_MIC_MUTE_DISABLE 0x365
61
62 struct dell_bios_data_token {
63 u16 tokenid;
64 u16 location;
65 u16 value;
66 };
67
68 struct __attribute__ ((__packed__)) dell_bios_calling_interface {
69 struct dmi_header header;
70 u16 cmd_io_addr;
71 u8 cmd_io_code;
72 u32 supported_cmds;
73 struct dell_bios_data_token damap[];
74 };
75
76 static struct dell_bios_data_token dell_mic_tokens[2];
77
dell_wmi_perform_query(struct app_wmi_args * args)78 static int dell_wmi_perform_query(struct app_wmi_args *args)
79 {
80 struct app_wmi_args *bios_return;
81 union acpi_object *obj;
82 struct acpi_buffer input;
83 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
84 acpi_status status;
85 u32 rc = -EINVAL;
86
87 input.length = 128;
88 input.pointer = args;
89
90 status = wmi_evaluate_method(DELL_APP_GUID, 0, 1, &input, &output);
91 if (!ACPI_SUCCESS(status))
92 goto err_out0;
93
94 obj = output.pointer;
95 if (!obj)
96 goto err_out0;
97
98 if (obj->type != ACPI_TYPE_BUFFER)
99 goto err_out1;
100
101 bios_return = (struct app_wmi_args *)obj->buffer.pointer;
102 rc = bios_return->res1;
103 if (rc)
104 goto err_out1;
105
106 memcpy(args, bios_return, sizeof(struct app_wmi_args));
107 rc = 0;
108
109 err_out1:
110 kfree(obj);
111 err_out0:
112 return rc;
113 }
114
find_micmute_tokens(const struct dmi_header * dm,void * dummy)115 static void __init find_micmute_tokens(const struct dmi_header *dm, void *dummy)
116 {
117 struct dell_bios_calling_interface *calling_interface;
118 struct dell_bios_data_token *token;
119 int token_size = sizeof(struct dell_bios_data_token);
120 int i = 0;
121
122 if (dm->type == 0xda && dm->length > 17) {
123 calling_interface = container_of(dm,
124 struct dell_bios_calling_interface, header);
125
126 token = &calling_interface->damap[i];
127 while (token->tokenid != 0xffff) {
128 if (token->tokenid == GLOBAL_MIC_MUTE_DISABLE)
129 memcpy(&dell_mic_tokens[0], token, token_size);
130 else if (token->tokenid == GLOBAL_MIC_MUTE_ENABLE)
131 memcpy(&dell_mic_tokens[1], token, token_size);
132
133 i++;
134 token = &calling_interface->damap[i];
135 }
136 }
137 }
138
dell_micmute_led_set(int state)139 static int dell_micmute_led_set(int state)
140 {
141 struct app_wmi_args args;
142 struct dell_bios_data_token *token;
143
144 if (!wmi_has_guid(DELL_APP_GUID))
145 return -ENODEV;
146
147 if (state == 0 || state == 1)
148 token = &dell_mic_tokens[state];
149 else
150 return -EINVAL;
151
152 memset(&args, 0, sizeof(struct app_wmi_args));
153
154 args.class = 1;
155 args.arg1 = token->location;
156 args.arg2 = token->value;
157
158 dell_wmi_perform_query(&args);
159
160 return state;
161 }
162
dell_app_wmi_led_set(int whichled,int on)163 int dell_app_wmi_led_set(int whichled, int on)
164 {
165 int state = 0;
166
167 switch (whichled) {
168 case DELL_LED_MICMUTE:
169 state = dell_micmute_led_set(on);
170 break;
171 default:
172 pr_warn("led type %x is not supported\n", whichled);
173 break;
174 }
175
176 return state;
177 }
178 EXPORT_SYMBOL_GPL(dell_app_wmi_led_set);
179
dell_micmute_led_init(void)180 static int __init dell_micmute_led_init(void)
181 {
182 memset(dell_mic_tokens, 0, sizeof(struct dell_bios_data_token) * 2);
183 dmi_walk(find_micmute_tokens, NULL);
184
185 return 0;
186 }
187
188 struct bios_args {
189 unsigned char length;
190 unsigned char result_code;
191 unsigned char device_id;
192 unsigned char command;
193 unsigned char on_time;
194 unsigned char off_time;
195 };
196
dell_led_perform_fn(u8 length,u8 result_code,u8 device_id,u8 command,u8 on_time,u8 off_time)197 static int dell_led_perform_fn(u8 length,
198 u8 result_code,
199 u8 device_id,
200 u8 command,
201 u8 on_time,
202 u8 off_time)
203 {
204 struct bios_args *bios_return;
205 u8 return_code;
206 union acpi_object *obj;
207 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
208 struct acpi_buffer input;
209 acpi_status status;
210
211 struct bios_args args;
212 args.length = length;
213 args.result_code = result_code;
214 args.device_id = device_id;
215 args.command = command;
216 args.on_time = on_time;
217 args.off_time = off_time;
218
219 input.length = sizeof(struct bios_args);
220 input.pointer = &args;
221
222 status = wmi_evaluate_method(DELL_LED_BIOS_GUID,
223 1,
224 1,
225 &input,
226 &output);
227
228 if (ACPI_FAILURE(status))
229 return status;
230
231 obj = output.pointer;
232
233 if (!obj)
234 return -EINVAL;
235 else if (obj->type != ACPI_TYPE_BUFFER) {
236 kfree(obj);
237 return -EINVAL;
238 }
239
240 bios_return = ((struct bios_args *)obj->buffer.pointer);
241 return_code = bios_return->result_code;
242
243 kfree(obj);
244
245 return return_code;
246 }
247
led_on(void)248 static int led_on(void)
249 {
250 return dell_led_perform_fn(3, /* Length of command */
251 INTERFACE_ERROR, /* Init to INTERFACE_ERROR */
252 DEVICE_ID_PANEL_BACK, /* Device ID */
253 CMD_LED_ON, /* Command */
254 0, /* not used */
255 0); /* not used */
256 }
257
led_off(void)258 static int led_off(void)
259 {
260 return dell_led_perform_fn(3, /* Length of command */
261 INTERFACE_ERROR, /* Init to INTERFACE_ERROR */
262 DEVICE_ID_PANEL_BACK, /* Device ID */
263 CMD_LED_OFF, /* Command */
264 0, /* not used */
265 0); /* not used */
266 }
267
led_blink(unsigned char on_eighths,unsigned char off_eighths)268 static int led_blink(unsigned char on_eighths,
269 unsigned char off_eighths)
270 {
271 return dell_led_perform_fn(5, /* Length of command */
272 INTERFACE_ERROR, /* Init to INTERFACE_ERROR */
273 DEVICE_ID_PANEL_BACK, /* Device ID */
274 CMD_LED_BLINK, /* Command */
275 on_eighths, /* blink on in eigths of a second */
276 off_eighths); /* blink off in eights of a second */
277 }
278
dell_led_set(struct led_classdev * led_cdev,enum led_brightness value)279 static void dell_led_set(struct led_classdev *led_cdev,
280 enum led_brightness value)
281 {
282 if (value == LED_OFF)
283 led_off();
284 else
285 led_on();
286 }
287
dell_led_blink(struct led_classdev * led_cdev,unsigned long * delay_on,unsigned long * delay_off)288 static int dell_led_blink(struct led_classdev *led_cdev,
289 unsigned long *delay_on,
290 unsigned long *delay_off)
291 {
292 unsigned long on_eighths;
293 unsigned long off_eighths;
294
295 /* The Dell LED delay is based on 125ms intervals.
296 Need to round up to next interval. */
297
298 on_eighths = (*delay_on + 124) / 125;
299 if (0 == on_eighths)
300 on_eighths = 1;
301 if (on_eighths > 255)
302 on_eighths = 255;
303 *delay_on = on_eighths * 125;
304
305 off_eighths = (*delay_off + 124) / 125;
306 if (0 == off_eighths)
307 off_eighths = 1;
308 if (off_eighths > 255)
309 off_eighths = 255;
310 *delay_off = off_eighths * 125;
311
312 led_blink(on_eighths, off_eighths);
313
314 return 0;
315 }
316
317 static struct led_classdev dell_led = {
318 .name = "dell::lid",
319 .brightness = LED_OFF,
320 .max_brightness = 1,
321 .brightness_set = dell_led_set,
322 .blink_set = dell_led_blink,
323 .flags = LED_CORE_SUSPENDRESUME,
324 };
325
dell_led_init(void)326 static int __init dell_led_init(void)
327 {
328 int error = 0;
329
330 if (!wmi_has_guid(DELL_LED_BIOS_GUID) && !wmi_has_guid(DELL_APP_GUID))
331 return -ENODEV;
332
333 if (wmi_has_guid(DELL_APP_GUID))
334 error = dell_micmute_led_init();
335
336 if (wmi_has_guid(DELL_LED_BIOS_GUID)) {
337 error = led_off();
338 if (error != 0)
339 return -ENODEV;
340
341 error = led_classdev_register(NULL, &dell_led);
342 }
343
344 return error;
345 }
346
dell_led_exit(void)347 static void __exit dell_led_exit(void)
348 {
349 int error = 0;
350
351 if (wmi_has_guid(DELL_LED_BIOS_GUID)) {
352 error = led_off();
353 if (error == 0)
354 led_classdev_unregister(&dell_led);
355 }
356 }
357
358 module_init(dell_led_init);
359 module_exit(dell_led_exit);
360