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 */
28static u32 oxp_mutex;
29
30#define ACPI_LOCK_DELAY_MS 500
31
32static bool lock_global_acpi_lock(void)
33{
34 return ACPI_SUCCESS(acpi_acquire_global_lock(ACPI_LOCK_DELAY_MS, &oxp_mutex));
35}
36
37static bool unlock_global_acpi_lock(void)
38{
39 return ACPI_SUCCESS(acpi_release_global_lock(oxp_mutex));
40}
41
42enum 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
54static 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
73static 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 */
148static 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(addr: reg + i, val: &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
172static 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(addr: reg, val: value);
180
181 if (!unlock_global_acpi_lock())
182 return -EBUSY;
183
184 return ret;
185}
186
187/* Turbo button toggle functions */
188static 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, value: val);
207}
208
209static 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, value: val);
228}
229
230/* Callbacks for turbo toggle attribute */
231static 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
245static 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(s: buf, res: &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
267static 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, size: 1, val: &val);
287 if (retval)
288 return retval;
289
290 return sysfs_emit(buf, fmt: "%d\n", !!val);
291}
292
293static DEVICE_ATTR_RW(tt_toggle);
294
295/* PWM enable/disable functions */
296static int oxp_pwm_enable(void)
297{
298 return write_to_ec(OXP_SENSOR_PWM_ENABLE_REG, value: 0x01);
299}
300
301static int oxp_pwm_disable(void)
302{
303 return write_to_ec(OXP_SENSOR_PWM_ENABLE_REG, value: 0x00);
304}
305
306/* Callbacks for hwmon interface */
307static 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
320static 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, size: 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, size: 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, size: 1, val);
358 default:
359 break;
360 }
361 break;
362 default:
363 break;
364 }
365 return -EOPNOTSUPP;
366}
367
368static 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, value: 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 */
410static 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
418static struct attribute *oxp_ec_attrs[] = {
419 &dev_attr_tt_toggle.attr,
420 NULL
421};
422
423static struct attribute_group oxp_ec_attribute_group = {
424 .is_visible = tt_toggle_is_visible,
425 .attrs = oxp_ec_attrs,
426};
427
428static const struct attribute_group *oxp_ec_groups[] = {
429 &oxp_ec_attribute_group,
430 NULL
431};
432
433static 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
439static 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 */
445static 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, name: "oxpec", NULL,
451 info: &oxp_ec_chip_info, NULL);
452
453 return PTR_ERR_OR_ZERO(ptr: hwdev);
454}
455
456static 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
464static struct platform_device *oxp_platform_device;
465
466static 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(list: 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(ptr: oxp_platform_device);
488}
489
490static void __exit oxp_platform_exit(void)
491{
492 platform_device_unregister(oxp_platform_device);
493 platform_driver_unregister(&oxp_platform_driver);
494}
495
496MODULE_DEVICE_TABLE(dmi, dmi_table);
497
498module_init(oxp_platform_init);
499module_exit(oxp_platform_exit);
500
501MODULE_AUTHOR("Joaquín Ignacio Aramendía <samsagax@gmail.com>");
502MODULE_DESCRIPTION("Platform driver that handles EC sensors of OneXPlayer devices");
503MODULE_LICENSE("GPL");
504

source code of linux/drivers/hwmon/oxp-sensors.c