1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * System76 ACPI Driver
4  *
5  * Copyright (C) 2019 System76
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/acpi.h>
13 #include <linux/init.h>
14 #include <linux/kernel.h>
15 #include <linux/leds.h>
16 #include <linux/module.h>
17 #include <linux/pci_ids.h>
18 #include <linux/types.h>
19 
20 struct system76_data {
21 	struct acpi_device *acpi_dev;
22 	struct led_classdev ap_led;
23 	struct led_classdev kb_led;
24 	enum led_brightness kb_brightness;
25 	enum led_brightness kb_toggle_brightness;
26 	int kb_color;
27 };
28 
29 static const struct acpi_device_id device_ids[] = {
30 	{"17761776", 0},
31 	{"", 0},
32 };
33 MODULE_DEVICE_TABLE(acpi, device_ids);
34 
35 // Array of keyboard LED brightness levels
36 static const enum led_brightness kb_levels[] = {
37 	48,
38 	72,
39 	96,
40 	144,
41 	192,
42 	255
43 };
44 
45 // Array of keyboard LED colors in 24-bit RGB format
46 static const int kb_colors[] = {
47 	0xFFFFFF,
48 	0x0000FF,
49 	0xFF0000,
50 	0xFF00FF,
51 	0x00FF00,
52 	0x00FFFF,
53 	0xFFFF00
54 };
55 
56 // Get a System76 ACPI device value by name
57 static int system76_get(struct system76_data *data, char *method)
58 {
59 	acpi_handle handle;
60 	acpi_status status;
61 	unsigned long long ret = 0;
62 
63 	handle = acpi_device_handle(data->acpi_dev);
64 	status = acpi_evaluate_integer(handle, method, NULL, &ret);
65 	if (ACPI_SUCCESS(status))
66 		return (int)ret;
67 	else
68 		return -1;
69 }
70 
71 // Set a System76 ACPI device value by name
72 static int system76_set(struct system76_data *data, char *method, int value)
73 {
74 	union acpi_object obj;
75 	struct acpi_object_list obj_list;
76 	acpi_handle handle;
77 	acpi_status status;
78 
79 	obj.type = ACPI_TYPE_INTEGER;
80 	obj.integer.value = value;
81 	obj_list.count = 1;
82 	obj_list.pointer = &obj;
83 	handle = acpi_device_handle(data->acpi_dev);
84 	status = acpi_evaluate_object(handle, method, &obj_list, NULL);
85 	if (ACPI_SUCCESS(status))
86 		return 0;
87 	else
88 		return -1;
89 }
90 
91 // Get the airplane mode LED brightness
92 static enum led_brightness ap_led_get(struct led_classdev *led)
93 {
94 	struct system76_data *data;
95 	int value;
96 
97 	data = container_of(led, struct system76_data, ap_led);
98 	value = system76_get(data, "GAPL");
99 	if (value > 0)
100 		return (enum led_brightness)value;
101 	else
102 		return LED_OFF;
103 }
104 
105 // Set the airplane mode LED brightness
106 static int ap_led_set(struct led_classdev *led, enum led_brightness value)
107 {
108 	struct system76_data *data;
109 
110 	data = container_of(led, struct system76_data, ap_led);
111 	return system76_set(data, "SAPL", value == LED_OFF ? 0 : 1);
112 }
113 
114 // Get the last set keyboard LED brightness
115 static enum led_brightness kb_led_get(struct led_classdev *led)
116 {
117 	struct system76_data *data;
118 
119 	data = container_of(led, struct system76_data, kb_led);
120 	return data->kb_brightness;
121 }
122 
123 // Set the keyboard LED brightness
124 static int kb_led_set(struct led_classdev *led, enum led_brightness value)
125 {
126 	struct system76_data *data;
127 
128 	data = container_of(led, struct system76_data, kb_led);
129 	data->kb_brightness = value;
130 	return system76_set(data, "SKBL", (int)data->kb_brightness);
131 }
132 
133 // Get the last set keyboard LED color
134 static ssize_t kb_led_color_show(
135 	struct device *dev,
136 	struct device_attribute *dev_attr,
137 	char *buf)
138 {
139 	struct led_classdev *led;
140 	struct system76_data *data;
141 
142 	led = (struct led_classdev *)dev->driver_data;
143 	data = container_of(led, struct system76_data, kb_led);
144 	return sprintf(buf, "%06X\n", data->kb_color);
145 }
146 
147 // Set the keyboard LED color
148 static ssize_t kb_led_color_store(
149 	struct device *dev,
150 	struct device_attribute *dev_attr,
151 	const char *buf,
152 	size_t size)
153 {
154 	struct led_classdev *led;
155 	struct system76_data *data;
156 	unsigned int val;
157 	int ret;
158 
159 	led = (struct led_classdev *)dev->driver_data;
160 	data = container_of(led, struct system76_data, kb_led);
161 	ret = kstrtouint(buf, 16, &val);
162 	if (ret)
163 		return ret;
164 	if (val > 0xFFFFFF)
165 		return -EINVAL;
166 	data->kb_color = (int)val;
167 	system76_set(data, "SKBC", data->kb_color);
168 
169 	return size;
170 }
171 
172 static const struct device_attribute kb_led_color_dev_attr = {
173 	.attr = {
174 		.name = "color",
175 		.mode = 0644,
176 	},
177 	.show = kb_led_color_show,
178 	.store = kb_led_color_store,
179 };
180 
181 // Notify that the keyboard LED was changed by hardware
182 static void kb_led_notify(struct system76_data *data)
183 {
184 	led_classdev_notify_brightness_hw_changed(
185 		&data->kb_led,
186 		data->kb_brightness
187 	);
188 }
189 
190 // Read keyboard LED brightness as set by hardware
191 static void kb_led_hotkey_hardware(struct system76_data *data)
192 {
193 	int value;
194 
195 	value = system76_get(data, "GKBL");
196 	if (value < 0)
197 		return;
198 	data->kb_brightness = value;
199 	kb_led_notify(data);
200 }
201 
202 // Toggle the keyboard LED
203 static void kb_led_hotkey_toggle(struct system76_data *data)
204 {
205 	if (data->kb_brightness > 0) {
206 		data->kb_toggle_brightness = data->kb_brightness;
207 		kb_led_set(&data->kb_led, 0);
208 	} else {
209 		kb_led_set(&data->kb_led, data->kb_toggle_brightness);
210 	}
211 	kb_led_notify(data);
212 }
213 
214 // Decrease the keyboard LED brightness
215 static void kb_led_hotkey_down(struct system76_data *data)
216 {
217 	int i;
218 
219 	if (data->kb_brightness > 0) {
220 		for (i = ARRAY_SIZE(kb_levels); i > 0; i--) {
221 			if (kb_levels[i - 1] < data->kb_brightness) {
222 				kb_led_set(&data->kb_led, kb_levels[i - 1]);
223 				break;
224 			}
225 		}
226 	} else {
227 		kb_led_set(&data->kb_led, data->kb_toggle_brightness);
228 	}
229 	kb_led_notify(data);
230 }
231 
232 // Increase the keyboard LED brightness
233 static void kb_led_hotkey_up(struct system76_data *data)
234 {
235 	int i;
236 
237 	if (data->kb_brightness > 0) {
238 		for (i = 0; i < ARRAY_SIZE(kb_levels); i++) {
239 			if (kb_levels[i] > data->kb_brightness) {
240 				kb_led_set(&data->kb_led, kb_levels[i]);
241 				break;
242 			}
243 		}
244 	} else {
245 		kb_led_set(&data->kb_led, data->kb_toggle_brightness);
246 	}
247 	kb_led_notify(data);
248 }
249 
250 // Cycle the keyboard LED color
251 static void kb_led_hotkey_color(struct system76_data *data)
252 {
253 	int i;
254 
255 	if (data->kb_color < 0)
256 		return;
257 	if (data->kb_brightness > 0) {
258 		for (i = 0; i < ARRAY_SIZE(kb_colors); i++) {
259 			if (kb_colors[i] == data->kb_color)
260 				break;
261 		}
262 		i += 1;
263 		if (i >= ARRAY_SIZE(kb_colors))
264 			i = 0;
265 		data->kb_color = kb_colors[i];
266 		system76_set(data, "SKBC", data->kb_color);
267 	} else {
268 		kb_led_set(&data->kb_led, data->kb_toggle_brightness);
269 	}
270 	kb_led_notify(data);
271 }
272 
273 // Handle ACPI notification
274 static void system76_notify(struct acpi_device *acpi_dev, u32 event)
275 {
276 	struct system76_data *data;
277 
278 	data = acpi_driver_data(acpi_dev);
279 	switch (event) {
280 	case 0x80:
281 		kb_led_hotkey_hardware(data);
282 		break;
283 	case 0x81:
284 		kb_led_hotkey_toggle(data);
285 		break;
286 	case 0x82:
287 		kb_led_hotkey_down(data);
288 		break;
289 	case 0x83:
290 		kb_led_hotkey_up(data);
291 		break;
292 	case 0x84:
293 		kb_led_hotkey_color(data);
294 		break;
295 	}
296 }
297 
298 // Add a System76 ACPI device
299 static int system76_add(struct acpi_device *acpi_dev)
300 {
301 	struct system76_data *data;
302 	int err;
303 
304 	data = devm_kzalloc(&acpi_dev->dev, sizeof(*data), GFP_KERNEL);
305 	if (!data)
306 		return -ENOMEM;
307 	acpi_dev->driver_data = data;
308 	data->acpi_dev = acpi_dev;
309 
310 	err = system76_get(data, "INIT");
311 	if (err)
312 		return err;
313 	data->ap_led.name = "system76_acpi::airplane";
314 	data->ap_led.flags = LED_CORE_SUSPENDRESUME;
315 	data->ap_led.brightness_get = ap_led_get;
316 	data->ap_led.brightness_set_blocking = ap_led_set;
317 	data->ap_led.max_brightness = 1;
318 	data->ap_led.default_trigger = "rfkill-none";
319 	err = devm_led_classdev_register(&acpi_dev->dev, &data->ap_led);
320 	if (err)
321 		return err;
322 
323 	data->kb_led.name = "system76_acpi::kbd_backlight";
324 	data->kb_led.flags = LED_BRIGHT_HW_CHANGED | LED_CORE_SUSPENDRESUME;
325 	data->kb_led.brightness_get = kb_led_get;
326 	data->kb_led.brightness_set_blocking = kb_led_set;
327 	if (acpi_has_method(acpi_device_handle(data->acpi_dev), "SKBC")) {
328 		data->kb_led.max_brightness = 255;
329 		data->kb_toggle_brightness = 72;
330 		data->kb_color = 0xffffff;
331 		system76_set(data, "SKBC", data->kb_color);
332 	} else {
333 		data->kb_led.max_brightness = 5;
334 		data->kb_color = -1;
335 	}
336 	err = devm_led_classdev_register(&acpi_dev->dev, &data->kb_led);
337 	if (err)
338 		return err;
339 
340 	if (data->kb_color >= 0) {
341 		err = device_create_file(
342 			data->kb_led.dev,
343 			&kb_led_color_dev_attr
344 		);
345 		if (err)
346 			return err;
347 	}
348 
349 	return 0;
350 }
351 
352 // Remove a System76 ACPI device
353 static int system76_remove(struct acpi_device *acpi_dev)
354 {
355 	struct system76_data *data;
356 
357 	data = acpi_driver_data(acpi_dev);
358 	if (data->kb_color >= 0)
359 		device_remove_file(data->kb_led.dev, &kb_led_color_dev_attr);
360 
361 	devm_led_classdev_unregister(&acpi_dev->dev, &data->ap_led);
362 
363 	devm_led_classdev_unregister(&acpi_dev->dev, &data->kb_led);
364 
365 	system76_get(data, "FINI");
366 
367 	return 0;
368 }
369 
370 static struct acpi_driver system76_driver = {
371 	.name = "System76 ACPI Driver",
372 	.class = "hotkey",
373 	.ids = device_ids,
374 	.ops = {
375 		.add = system76_add,
376 		.remove = system76_remove,
377 		.notify = system76_notify,
378 	},
379 };
380 module_acpi_driver(system76_driver);
381 
382 MODULE_DESCRIPTION("System76 ACPI Driver");
383 MODULE_AUTHOR("Jeremy Soller <jeremy@system76.com>");
384 MODULE_LICENSE("GPL");
385