xref: /linux/drivers/hwmon/oxp-sensors.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9) 
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Platform driver for OneXPlayer, AOK ZOE, and Aya Neo Handhelds that expose
4  * fan reading and control via hwmon sysfs.
5  *
6  * Old OXP boards have the same DMI strings and they are told apart by
7  * the boot cpu vendor (Intel/AMD). Currently only AMD boards are
8  * supported but the code is made to be simple to add other handheld
9  * boards in the future.
10  * Fan control is provided via pwm interface in the range [0-255].
11  * Old AMD boards use [0-100] as range in the EC, the written value is
12  * scaled to accommodate for that. Newer boards like the mini PRO and
13  * AOK ZOE are not scaled but have the same EC layout.
14  *
15  * Copyright (C) 2022 Joaquín I. Aramendía <samsagax@gmail.com>
16  */
17 
18 #include <linux/acpi.h>
19 #include <linux/dmi.h>
20 #include <linux/hwmon.h>
21 #include <linux/init.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/platform_device.h>
25 #include <linux/processor.h>
26 
27 /* Handle ACPI lock mechanism */
28 static u32 oxp_mutex;
29 
30 #define ACPI_LOCK_DELAY_MS	500
31 
32 static bool lock_global_acpi_lock(void)
33 {
34 	return ACPI_SUCCESS(acpi_acquire_global_lock(ACPI_LOCK_DELAY_MS, &oxp_mutex));
35 }
36 
37 static bool unlock_global_acpi_lock(void)
38 {
39 	return ACPI_SUCCESS(acpi_release_global_lock(oxp_mutex));
40 }
41 
42 enum oxp_board {
43 	aok_zoe_a1 = 1,
44 	aya_neo_2,
45 	aya_neo_air,
46 	aya_neo_air_plus_mendo,
47 	aya_neo_air_pro,
48 	aya_neo_geek,
49 	oxp_mini_amd,
50 	oxp_mini_amd_a07,
51 	oxp_mini_amd_pro,
52 };
53 
54 static enum oxp_board board;
55 
56 /* Fan reading and PWM */
57 #define OXP_SENSOR_FAN_REG		0x76 /* Fan reading is 2 registers long */
58 #define OXP_SENSOR_PWM_ENABLE_REG	0x4A /* PWM enable is 1 register long */
59 #define OXP_SENSOR_PWM_REG		0x4B /* PWM reading is 1 register long */
60 
61 /* Turbo button takeover function
62  * Older boards have different values and EC registers
63  * for the same function
64  */
65 #define OXP_OLD_TURBO_SWITCH_REG	0x1E
66 #define OXP_OLD_TURBO_TAKE_VAL		0x01
67 #define OXP_OLD_TURBO_RETURN_VAL	0x00
68 
69 #define OXP_TURBO_SWITCH_REG		0xF1
70 #define OXP_TURBO_TAKE_VAL		0x40
71 #define OXP_TURBO_RETURN_VAL		0x00
72 
73 static const struct dmi_system_id dmi_table[] = {
74 	{
75 		.matches = {
76 			DMI_MATCH(DMI_BOARD_VENDOR, "AOKZOE"),
77 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "AOKZOE A1 AR07"),
78 		},
79 		.driver_data = (void *)aok_zoe_a1,
80 	},
81 	{
82 		.matches = {
83 			DMI_MATCH(DMI_BOARD_VENDOR, "AOKZOE"),
84 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "AOKZOE A1 Pro"),
85 		},
86 		.driver_data = (void *)aok_zoe_a1,
87 	},
88 	{
89 		.matches = {
90 			DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"),
91 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "AYANEO 2"),
92 		},
93 		.driver_data = (void *)aya_neo_2,
94 	},
95 	{
96 		.matches = {
97 			DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"),
98 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "AIR"),
99 		},
100 		.driver_data = (void *)aya_neo_air,
101 	},
102 	{
103 		.matches = {
104 			DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"),
105 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "AB05-Mendocino"),
106 		},
107 		.driver_data = (void *)aya_neo_air_plus_mendo,
108 	},
109 	{
110 		.matches = {
111 			DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"),
112 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "AIR Pro"),
113 		},
114 		.driver_data = (void *)aya_neo_air_pro,
115 	},
116 	{
117 		.matches = {
118 			DMI_MATCH(DMI_BOARD_VENDOR, "AYANEO"),
119 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "GEEK"),
120 		},
121 		.driver_data = (void *)aya_neo_geek,
122 	},
123 	{
124 		.matches = {
125 			DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"),
126 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "ONE XPLAYER"),
127 		},
128 		.driver_data = (void *)oxp_mini_amd,
129 	},
130 	{
131 		.matches = {
132 			DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"),
133 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "ONEXPLAYER mini A07"),
134 		},
135 		.driver_data = (void *)oxp_mini_amd_a07,
136 	},
137 	{
138 		.matches = {
139 			DMI_MATCH(DMI_BOARD_VENDOR, "ONE-NETBOOK"),
140 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "ONEXPLAYER Mini Pro"),
141 		},
142 		.driver_data = (void *)oxp_mini_amd_pro,
143 	},
144 	{},
145 };
146 
147 /* Helper functions to handle EC read/write */
148 static int read_from_ec(u8 reg, int size, long *val)
149 {
150 	int i;
151 	int ret;
152 	u8 buffer;
153 
154 	if (!lock_global_acpi_lock())
155 		return -EBUSY;
156 
157 	*val = 0;
158 	for (i = 0; i < size; i++) {
159 		ret = ec_read(reg + i, &buffer);
160 		if (ret)
161 			return ret;
162 		*val <<= i * 8;
163 		*val += buffer;
164 	}
165 
166 	if (!unlock_global_acpi_lock())
167 		return -EBUSY;
168 
169 	return 0;
170 }
171 
172 static int write_to_ec(u8 reg, u8 value)
173 {
174 	int ret;
175 
176 	if (!lock_global_acpi_lock())
177 		return -EBUSY;
178 
179 	ret = ec_write(reg, value);
180 
181 	if (!unlock_global_acpi_lock())
182 		return -EBUSY;
183 
184 	return ret;
185 }
186 
187 /* Turbo button toggle functions */
188 static int tt_toggle_enable(void)
189 {
190 	u8 reg;
191 	u8 val;
192 
193 	switch (board) {
194 	case oxp_mini_amd_a07:
195 		reg = OXP_OLD_TURBO_SWITCH_REG;
196 		val = OXP_OLD_TURBO_TAKE_VAL;
197 		break;
198 	case oxp_mini_amd_pro:
199 	case aok_zoe_a1:
200 		reg = OXP_TURBO_SWITCH_REG;
201 		val = OXP_TURBO_TAKE_VAL;
202 		break;
203 	default:
204 		return -EINVAL;
205 	}
206 	return write_to_ec(reg, val);
207 }
208 
209 static int tt_toggle_disable(void)
210 {
211 	u8 reg;
212 	u8 val;
213 
214 	switch (board) {
215 	case oxp_mini_amd_a07:
216 		reg = OXP_OLD_TURBO_SWITCH_REG;
217 		val = OXP_OLD_TURBO_RETURN_VAL;
218 		break;
219 	case oxp_mini_amd_pro:
220 	case aok_zoe_a1:
221 		reg = OXP_TURBO_SWITCH_REG;
222 		val = OXP_TURBO_RETURN_VAL;
223 		break;
224 	default:
225 		return -EINVAL;
226 	}
227 	return write_to_ec(reg, val);
228 }
229 
230 /* Callbacks for turbo toggle attribute */
231 static umode_t tt_toggle_is_visible(struct kobject *kobj,
232 				    struct attribute *attr, int n)
233 {
234 	switch (board) {
235 	case aok_zoe_a1:
236 	case oxp_mini_amd_a07:
237 	case oxp_mini_amd_pro:
238 		return attr->mode;
239 	default:
240 		break;
241 	}
242 	return 0;
243 }
244 
245 static ssize_t tt_toggle_store(struct device *dev,
246 			       struct device_attribute *attr, const char *buf,
247 			       size_t count)
248 {
249 	int rval;
250 	bool value;
251 
252 	rval = kstrtobool(buf, &value);
253 	if (rval)
254 		return rval;
255 
256 	if (value) {
257 		rval = tt_toggle_enable();
258 	} else {
259 		rval = tt_toggle_disable();
260 	}
261 	if (rval)
262 		return rval;
263 
264 	return count;
265 }
266 
267 static ssize_t tt_toggle_show(struct device *dev,
268 			      struct device_attribute *attr, char *buf)
269 {
270 	int retval;
271 	u8 reg;
272 	long val;
273 
274 	switch (board) {
275 	case oxp_mini_amd_a07:
276 		reg = OXP_OLD_TURBO_SWITCH_REG;
277 		break;
278 	case oxp_mini_amd_pro:
279 	case aok_zoe_a1:
280 		reg = OXP_TURBO_SWITCH_REG;
281 		break;
282 	default:
283 		return -EINVAL;
284 	}
285 
286 	retval = read_from_ec(reg, 1, &val);
287 	if (retval)
288 		return retval;
289 
290 	return sysfs_emit(buf, "%d\n", !!val);
291 }
292 
293 static DEVICE_ATTR_RW(tt_toggle);
294 
295 /* PWM enable/disable functions */
296 static int oxp_pwm_enable(void)
297 {
298 	return write_to_ec(OXP_SENSOR_PWM_ENABLE_REG, 0x01);
299 }
300 
301 static int oxp_pwm_disable(void)
302 {
303 	return write_to_ec(OXP_SENSOR_PWM_ENABLE_REG, 0x00);
304 }
305 
306 /* Callbacks for hwmon interface */
307 static umode_t oxp_ec_hwmon_is_visible(const void *drvdata,
308 				       enum hwmon_sensor_types type, u32 attr, int channel)
309 {
310 	switch (type) {
311 	case hwmon_fan:
312 		return 0444;
313 	case hwmon_pwm:
314 		return 0644;
315 	default:
316 		return 0;
317 	}
318 }
319 
320 static int oxp_platform_read(struct device *dev, enum hwmon_sensor_types type,
321 			     u32 attr, int channel, long *val)
322 {
323 	int ret;
324 
325 	switch (type) {
326 	case hwmon_fan:
327 		switch (attr) {
328 		case hwmon_fan_input:
329 			return read_from_ec(OXP_SENSOR_FAN_REG, 2, val);
330 		default:
331 			break;
332 		}
333 		break;
334 	case hwmon_pwm:
335 		switch (attr) {
336 		case hwmon_pwm_input:
337 			ret = read_from_ec(OXP_SENSOR_PWM_REG, 1, val);
338 			if (ret)
339 				return ret;
340 			switch (board) {
341 			case aya_neo_2:
342 			case aya_neo_air:
343 			case aya_neo_air_plus_mendo:
344 			case aya_neo_air_pro:
345 			case aya_neo_geek:
346 			case oxp_mini_amd:
347 			case oxp_mini_amd_a07:
348 				*val = (*val * 255) / 100;
349 				break;
350 			case oxp_mini_amd_pro:
351 			case aok_zoe_a1:
352 			default:
353 				break;
354 			}
355 			return 0;
356 		case hwmon_pwm_enable:
357 			return read_from_ec(OXP_SENSOR_PWM_ENABLE_REG, 1, val);
358 		default:
359 			break;
360 		}
361 		break;
362 	default:
363 		break;
364 	}
365 	return -EOPNOTSUPP;
366 }
367 
368 static int oxp_platform_write(struct device *dev, enum hwmon_sensor_types type,
369 			      u32 attr, int channel, long val)
370 {
371 	switch (type) {
372 	case hwmon_pwm:
373 		switch (attr) {
374 		case hwmon_pwm_enable:
375 			if (val == 1)
376 				return oxp_pwm_enable();
377 			else if (val == 0)
378 				return oxp_pwm_disable();
379 			return -EINVAL;
380 		case hwmon_pwm_input:
381 			if (val < 0 || val > 255)
382 				return -EINVAL;
383 			switch (board) {
384 			case aya_neo_2:
385 			case aya_neo_air:
386 			case aya_neo_air_plus_mendo:
387 			case aya_neo_air_pro:
388 			case aya_neo_geek:
389 			case oxp_mini_amd:
390 			case oxp_mini_amd_a07:
391 				val = (val * 100) / 255;
392 				break;
393 			case aok_zoe_a1:
394 			case oxp_mini_amd_pro:
395 			default:
396 				break;
397 			}
398 			return write_to_ec(OXP_SENSOR_PWM_REG, val);
399 		default:
400 			break;
401 		}
402 		break;
403 	default:
404 		break;
405 	}
406 	return -EOPNOTSUPP;
407 }
408 
409 /* Known sensors in the OXP EC controllers */
410 static const struct hwmon_channel_info * const oxp_platform_sensors[] = {
411 	HWMON_CHANNEL_INFO(fan,
412 			   HWMON_F_INPUT),
413 	HWMON_CHANNEL_INFO(pwm,
414 			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
415 	NULL,
416 };
417 
418 static struct attribute *oxp_ec_attrs[] = {
419 	&dev_attr_tt_toggle.attr,
420 	NULL
421 };
422 
423 static struct attribute_group oxp_ec_attribute_group = {
424 	.is_visible = tt_toggle_is_visible,
425 	.attrs = oxp_ec_attrs,
426 };
427 
428 static const struct attribute_group *oxp_ec_groups[] = {
429 	&oxp_ec_attribute_group,
430 	NULL
431 };
432 
433 static const struct hwmon_ops oxp_ec_hwmon_ops = {
434 	.is_visible = oxp_ec_hwmon_is_visible,
435 	.read = oxp_platform_read,
436 	.write = oxp_platform_write,
437 };
438 
439 static const struct hwmon_chip_info oxp_ec_chip_info = {
440 	.ops = &oxp_ec_hwmon_ops,
441 	.info = oxp_platform_sensors,
442 };
443 
444 /* Initialization logic */
445 static int oxp_platform_probe(struct platform_device *pdev)
446 {
447 	struct device *dev = &pdev->dev;
448 	struct device *hwdev;
449 
450 	hwdev = devm_hwmon_device_register_with_info(dev, "oxpec", NULL,
451 						     &oxp_ec_chip_info, NULL);
452 
453 	return PTR_ERR_OR_ZERO(hwdev);
454 }
455 
456 static struct platform_driver oxp_platform_driver = {
457 	.driver = {
458 		.name = "oxp-platform",
459 		.dev_groups = oxp_ec_groups,
460 	},
461 	.probe = oxp_platform_probe,
462 };
463 
464 static struct platform_device *oxp_platform_device;
465 
466 static int __init oxp_platform_init(void)
467 {
468 	const struct dmi_system_id *dmi_entry;
469 
470 	/*
471 	 * Have to check for AMD processor here because DMI strings are the
472 	 * same between Intel and AMD boards, the only way to tell them apart
473 	 * is the CPU.
474 	 * Intel boards seem to have different EC registers and values to
475 	 * read/write.
476 	 */
477 	dmi_entry = dmi_first_match(dmi_table);
478 	if (!dmi_entry || boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
479 		return -ENODEV;
480 
481 	board = (enum oxp_board)(unsigned long)dmi_entry->driver_data;
482 
483 	oxp_platform_device =
484 		platform_create_bundle(&oxp_platform_driver,
485 				       oxp_platform_probe, NULL, 0, NULL, 0);
486 
487 	return PTR_ERR_OR_ZERO(oxp_platform_device);
488 }
489 
490 static void __exit oxp_platform_exit(void)
491 {
492 	platform_device_unregister(oxp_platform_device);
493 	platform_driver_unregister(&oxp_platform_driver);
494 }
495 
496 MODULE_DEVICE_TABLE(dmi, dmi_table);
497 
498 module_init(oxp_platform_init);
499 module_exit(oxp_platform_exit);
500 
501 MODULE_AUTHOR("Joaquín Ignacio Aramendía <samsagax@gmail.com>");
502 MODULE_DESCRIPTION("Platform driver that handles EC sensors of OneXPlayer devices");
503 MODULE_LICENSE("GPL");
504