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