gpd-fan.c

  1// SPDX-License-Identifier: GPL-2.0+
  2
  3/* Platform driver for GPD devices that expose fan control via hwmon sysfs.
  4 *
  5 * Fan control is provided via pwm interface in the range [0-255].
  6 * Each model has a different range in the EC, the written value is scaled to
  7 * accommodate for that.
  8 *
  9 * Based on this repo:
 10 * https://github.com/Cryolitia/gpd-fan-driver
 11 *
 12 * Copyright (c) 2024 Cryolitia PukNgae
 13 */
 14
 15#include <linux/dmi.h>
 16#include <linux/hwmon.h>
 17#include <linux/io.h>
 18#include <linux/ioport.h>
 19#include <linux/kernel.h>
 20#include <linux/module.h>
 21#include <linux/platform_device.h>
 22
 23#define DRIVER_NAME "gpdfan"
 24#define GPD_PWM_CTR_OFFSET 0x1841
 25
 26static char *gpd_fan_board = "";
 27module_param(gpd_fan_board, charp, 0444);
 28
 29enum gpd_board {
 30	win_mini,
 31	win4_6800u,
 32	win_max_2,
 33	duo,
 34};
 35
 36enum FAN_PWM_ENABLE {
 37	DISABLE		= 0,
 38	MANUAL		= 1,
 39	AUTOMATIC	= 2,
 40};
 41
 42static struct {
 43	enum FAN_PWM_ENABLE pwm_enable;
 44	u8 pwm_value;
 45
 46	const struct gpd_fan_drvdata *drvdata;
 47} gpd_driver_priv;
 48
 49struct gpd_fan_drvdata {
 50	const char *board_name; // Board name for module param comparison
 51	const enum gpd_board board;
 52
 53	const u8 addr_port;
 54	const u8 data_port;
 55	const u16 manual_control_enable;
 56	const u16 rpm_read;
 57	const u16 pwm_write;
 58	const u16 pwm_max;
 59};
 60
 61static struct gpd_fan_drvdata gpd_win_mini_drvdata = {
 62	.board_name		= "win_mini",
 63	.board			= win_mini,
 64
 65	.addr_port		= 0x4E,
 66	.data_port		= 0x4F,
 67	.manual_control_enable	= 0x047A,
 68	.rpm_read		= 0x0478,
 69	.pwm_write		= 0x047A,
 70	.pwm_max		= 244,
 71};
 72
 73static struct gpd_fan_drvdata gpd_duo_drvdata = {
 74	.board_name		= "duo",
 75	.board			= duo,
 76
 77	.addr_port		= 0x4E,
 78	.data_port		= 0x4F,
 79	.manual_control_enable	= 0x047A,
 80	.rpm_read		= 0x0478,
 81	.pwm_write		= 0x047A,
 82	.pwm_max		= 244,
 83};
 84
 85static struct gpd_fan_drvdata gpd_win4_drvdata = {
 86	.board_name		= "win4",
 87	.board			= win4_6800u,
 88
 89	.addr_port		= 0x2E,
 90	.data_port		= 0x2F,
 91	.manual_control_enable	= 0xC311,
 92	.rpm_read		= 0xC880,
 93	.pwm_write		= 0xC311,
 94	.pwm_max		= 127,
 95};
 96
 97static struct gpd_fan_drvdata gpd_wm2_drvdata = {
 98	.board_name		= "wm2",
 99	.board			= win_max_2,
100
101	.addr_port		= 0x4E,
102	.data_port		= 0x4F,
103	.manual_control_enable	= 0x0275,
104	.rpm_read		= 0x0218,
105	.pwm_write		= 0x1809,
106	.pwm_max		= 184,
107};
108
109static const struct dmi_system_id dmi_table[] = {
110	{
111		// GPD Win Mini
112		// GPD Win Mini with AMD Ryzen 8840U
113		.matches = {
114			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
115			DMI_MATCH(DMI_PRODUCT_NAME, "G1617-01")
116		},
117		.driver_data = &gpd_win_mini_drvdata,
118	},
119	{
120		// GPD Win Mini
121		// GPD Win Mini with AMD Ryzen HX370
122		.matches = {
123			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
124			DMI_MATCH(DMI_PRODUCT_NAME, "G1617-02")
125		},
126		.driver_data = &gpd_win_mini_drvdata,
127	},
128	{
129		// GPD Win Mini
130		// GPD Win Mini with AMD Ryzen HX370
131		.matches = {
132			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
133			DMI_MATCH(DMI_PRODUCT_NAME, "G1617-02-L")
134		},
135		.driver_data = &gpd_win_mini_drvdata,
136	},
137	{
138		// GPD Win 4 with AMD Ryzen 6800U
139		.matches = {
140			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
141			DMI_MATCH(DMI_PRODUCT_NAME, "G1618-04"),
142			DMI_MATCH(DMI_BOARD_VERSION, "Default string"),
143		},
144		.driver_data = &gpd_win4_drvdata,
145	},
146	{
147		// GPD Win 4 with Ryzen 7840U
148		.matches = {
149			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
150			DMI_MATCH(DMI_PRODUCT_NAME, "G1618-04"),
151			DMI_MATCH(DMI_BOARD_VERSION, "Ver. 1.0"),
152		},
153		// Since 7840U, win4 uses the same drvdata as wm2
154		.driver_data = &gpd_wm2_drvdata,
155	},
156	{
157		// GPD Win 4 with Ryzen 7840U (another)
158		.matches = {
159			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
160			DMI_MATCH(DMI_PRODUCT_NAME, "G1618-04"),
161			DMI_MATCH(DMI_BOARD_VERSION, "Ver.1.0"),
162		},
163		.driver_data = &gpd_wm2_drvdata,
164	},
165	{
166		// GPD Win Max 2 with Ryzen 6800U
167		// GPD Win Max 2 2023 with Ryzen 7840U
168		// GPD Win Max 2 2024 with Ryzen 8840U
169		.matches = {
170			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
171			DMI_MATCH(DMI_PRODUCT_NAME, "G1619-04"),
172		},
173		.driver_data = &gpd_wm2_drvdata,
174	},
175	{
176		// GPD Win Max 2 with AMD Ryzen HX370
177		.matches = {
178			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
179			DMI_MATCH(DMI_PRODUCT_NAME, "G1619-05"),
180		},
181		.driver_data = &gpd_wm2_drvdata,
182	},
183	{
184		// GPD Duo
185		.matches = {
186			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
187			DMI_MATCH(DMI_PRODUCT_NAME, "G1622-01"),
188		},
189		.driver_data = &gpd_duo_drvdata,
190	},
191	{
192		// GPD Duo (another)
193		.matches = {
194			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
195			DMI_MATCH(DMI_PRODUCT_NAME, "G1622-01-L"),
196		},
197		.driver_data = &gpd_duo_drvdata,
198	},
199	{
200		// GPD Pocket 4
201		.matches = {
202			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
203			DMI_MATCH(DMI_PRODUCT_NAME, "G1628-04"),
204		},
205		.driver_data = &gpd_win_mini_drvdata,
206	},
207	{
208		// GPD Pocket 4 (another)
209		.matches = {
210			DMI_MATCH(DMI_SYS_VENDOR, "GPD"),
211			DMI_MATCH(DMI_PRODUCT_NAME, "G1628-04-L"),
212		},
213		.driver_data = &gpd_win_mini_drvdata,
214	},
215	{}
216};
217
218static const struct gpd_fan_drvdata *gpd_module_drvdata[] = {
219	&gpd_win_mini_drvdata, &gpd_win4_drvdata, &gpd_wm2_drvdata, NULL
220};
221
222// Helper functions to handle EC read/write
223static void gpd_ecram_read(u16 offset, u8 *val)
224{
225	u16 addr_port = gpd_driver_priv.drvdata->addr_port;
226	u16 data_port = gpd_driver_priv.drvdata->data_port;
227
228	outb(0x2E, addr_port);
229	outb(0x11, data_port);
230	outb(0x2F, addr_port);
231	outb((u8)((offset >> 8) & 0xFF), data_port);
232
233	outb(0x2E, addr_port);
234	outb(0x10, data_port);
235	outb(0x2F, addr_port);
236	outb((u8)(offset & 0xFF), data_port);
237
238	outb(0x2E, addr_port);
239	outb(0x12, data_port);
240	outb(0x2F, addr_port);
241	*val = inb(data_port);
242}
243
244static void gpd_ecram_write(u16 offset, u8 value)
245{
246	u16 addr_port = gpd_driver_priv.drvdata->addr_port;
247	u16 data_port = gpd_driver_priv.drvdata->data_port;
248
249	outb(0x2E, addr_port);
250	outb(0x11, data_port);
251	outb(0x2F, addr_port);
252	outb((u8)((offset >> 8) & 0xFF), data_port);
253
254	outb(0x2E, addr_port);
255	outb(0x10, data_port);
256	outb(0x2F, addr_port);
257	outb((u8)(offset & 0xFF), data_port);
258
259	outb(0x2E, addr_port);
260	outb(0x12, data_port);
261	outb(0x2F, addr_port);
262	outb(value, data_port);
263}
264
265static int gpd_generic_read_rpm(void)
266{
267	const struct gpd_fan_drvdata *const drvdata = gpd_driver_priv.drvdata;
268	u8 high, low;
269
270	gpd_ecram_read(drvdata->rpm_read, &high);
271	gpd_ecram_read(drvdata->rpm_read + 1, &low);
272
273	return (u16)high << 8 | low;
274}
275
276static int gpd_wm2_read_rpm(void)
277{
278	for (u16 pwm_ctr_offset = GPD_PWM_CTR_OFFSET;
279	     pwm_ctr_offset <= GPD_PWM_CTR_OFFSET + 2; pwm_ctr_offset++) {
280		u8 PWMCTR;
281
282		gpd_ecram_read(pwm_ctr_offset, &PWMCTR);
283
284		if (PWMCTR != 0xB8)
285			gpd_ecram_write(pwm_ctr_offset, 0xB8);
286	}
287
288	return gpd_generic_read_rpm();
289}
290
291// Read value for fan1_input
292static int gpd_read_rpm(void)
293{
294	switch (gpd_driver_priv.drvdata->board) {
295	case win4_6800u:
296	case win_mini:
297	case duo:
298		return gpd_generic_read_rpm();
299	case win_max_2:
300		return gpd_wm2_read_rpm();
301	}
302
303	return 0;
304}
305
306static int gpd_wm2_read_pwm(void)
307{
308	const struct gpd_fan_drvdata *const drvdata = gpd_driver_priv.drvdata;
309	u8 var;
310
311	gpd_ecram_read(drvdata->pwm_write, &var);
312
313	// Match gpd_generic_write_pwm(u8) below
314	return DIV_ROUND_CLOSEST((var - 1) * 255, (drvdata->pwm_max - 1));
315}
316
317// Read value for pwm1
318static int gpd_read_pwm(void)
319{
320	switch (gpd_driver_priv.drvdata->board) {
321	case win_mini:
322	case duo:
323	case win4_6800u:
324		switch (gpd_driver_priv.pwm_enable) {
325		case DISABLE:
326			return 255;
327		case MANUAL:
328			return gpd_driver_priv.pwm_value;
329		case AUTOMATIC:
330			return -EOPNOTSUPP;
331		}
332		break;
333	case win_max_2:
334		return gpd_wm2_read_pwm();
335	}
336	return 0;
337}
338
339// PWM value's range in EC is 1 - pwm_max, cast 0 - 255 to it.
340static inline u8 gpd_cast_pwm_range(u8 val)
341{
342	const struct gpd_fan_drvdata *const drvdata = gpd_driver_priv.drvdata;
343
344	return DIV_ROUND_CLOSEST(val * (drvdata->pwm_max - 1), 255) + 1;
345}
346
347static void gpd_generic_write_pwm(u8 val)
348{
349	const struct gpd_fan_drvdata *const drvdata = gpd_driver_priv.drvdata;
350	u8 pwm_reg;
351
352	pwm_reg = gpd_cast_pwm_range(val);
353	gpd_ecram_write(drvdata->pwm_write, pwm_reg);
354}
355
356static void gpd_duo_write_pwm(u8 val)
357{
358	const struct gpd_fan_drvdata *const drvdata = gpd_driver_priv.drvdata;
359	u8 pwm_reg;
360
361	pwm_reg = gpd_cast_pwm_range(val);
362	gpd_ecram_write(drvdata->pwm_write, pwm_reg);
363	gpd_ecram_write(drvdata->pwm_write + 1, pwm_reg);
364}
365
366// Write value for pwm1
367static int gpd_write_pwm(u8 val)
368{
369	if (gpd_driver_priv.pwm_enable != MANUAL)
370		return -EPERM;
371
372	switch (gpd_driver_priv.drvdata->board) {
373	case duo:
374		gpd_duo_write_pwm(val);
375		break;
376	case win_mini:
377	case win4_6800u:
378	case win_max_2:
379		gpd_generic_write_pwm(val);
380		break;
381	}
382
383	return 0;
384}
385
386static void gpd_win_mini_set_pwm_enable(enum FAN_PWM_ENABLE pwm_enable)
387{
388	switch (pwm_enable) {
389	case DISABLE:
390		gpd_generic_write_pwm(255);
391		break;
392	case MANUAL:
393		gpd_generic_write_pwm(gpd_driver_priv.pwm_value);
394		break;
395	case AUTOMATIC:
396		gpd_ecram_write(gpd_driver_priv.drvdata->pwm_write, 0);
397		break;
398	}
399}
400
401static void gpd_duo_set_pwm_enable(enum FAN_PWM_ENABLE pwm_enable)
402{
403	switch (pwm_enable) {
404	case DISABLE:
405		gpd_duo_write_pwm(255);
406		break;
407	case MANUAL:
408		gpd_duo_write_pwm(gpd_driver_priv.pwm_value);
409		break;
410	case AUTOMATIC:
411		gpd_ecram_write(gpd_driver_priv.drvdata->pwm_write, 0);
412		break;
413	}
414}
415
416static void gpd_wm2_set_pwm_enable(enum FAN_PWM_ENABLE enable)
417{
418	const struct gpd_fan_drvdata *const drvdata = gpd_driver_priv.drvdata;
419
420	switch (enable) {
421	case DISABLE:
422		gpd_generic_write_pwm(255);
423		gpd_ecram_write(drvdata->manual_control_enable, 1);
424		break;
425	case MANUAL:
426		gpd_generic_write_pwm(gpd_driver_priv.pwm_value);
427		gpd_ecram_write(drvdata->manual_control_enable, 1);
428		break;
429	case AUTOMATIC:
430		gpd_ecram_write(drvdata->manual_control_enable, 0);
431		break;
432	}
433}
434
435// Write value for pwm1_enable
436static void gpd_set_pwm_enable(enum FAN_PWM_ENABLE enable)
437{
438	if (enable == MANUAL)
439		// Set pwm_value to max firstly when switching to manual mode, in
440		// consideration of device safety.
441		gpd_driver_priv.pwm_value = 255;
442
443	switch (gpd_driver_priv.drvdata->board) {
444	case win_mini:
445	case win4_6800u:
446		gpd_win_mini_set_pwm_enable(enable);
447		break;
448	case duo:
449		gpd_duo_set_pwm_enable(enable);
450		break;
451	case win_max_2:
452		gpd_wm2_set_pwm_enable(enable);
453		break;
454	}
455}
456
457static umode_t gpd_fan_hwmon_is_visible(__always_unused const void *drvdata,
458					enum hwmon_sensor_types type, u32 attr,
459					__always_unused int channel)
460{
461	if (type == hwmon_fan && attr == hwmon_fan_input) {
462		return 0444;
463	} else if (type == hwmon_pwm) {
464		switch (attr) {
465		case hwmon_pwm_enable:
466		case hwmon_pwm_input:
467			return 0644;
468		default:
469			return 0;
470		}
471	}
472	return 0;
473}
474
475static int gpd_fan_hwmon_read(__always_unused struct device *dev,
476			      enum hwmon_sensor_types type, u32 attr,
477			      __always_unused int channel, long *val)
478{
479	int ret;
480
481	if (type == hwmon_fan) {
482		if (attr == hwmon_fan_input) {
483			ret = gpd_read_rpm();
484
485			if (ret < 0)
486				return ret;
487
488			*val = ret;
489			return 0;
490		}
491	} else if (type == hwmon_pwm) {
492		switch (attr) {
493		case hwmon_pwm_enable:
494			*val = gpd_driver_priv.pwm_enable;
495			return 0;
496		case hwmon_pwm_input:
497			ret = gpd_read_pwm();
498
499			if (ret < 0)
500				return ret;
501
502			*val = ret;
503			return 0;
504		}
505	}
506
507	return -EOPNOTSUPP;
508}
509
510static int gpd_fan_hwmon_write(__always_unused struct device *dev,
511			       enum hwmon_sensor_types type, u32 attr,
512			       __always_unused int channel, long val)
513{
514	if (type == hwmon_pwm) {
515		switch (attr) {
516		case hwmon_pwm_enable:
517			if (!in_range(val, 0, 3))
518				return -EINVAL;
519
520			gpd_driver_priv.pwm_enable = val;
521
522			gpd_set_pwm_enable(gpd_driver_priv.pwm_enable);
523			return 0;
524		case hwmon_pwm_input:
525			if (!in_range(val, 0, 256))
526				return -EINVAL;
527
528			gpd_driver_priv.pwm_value = val;
529
530			return gpd_write_pwm(val);
531		}
532	}
533
534	return -EOPNOTSUPP;
535}
536
537static const struct hwmon_ops gpd_fan_ops = {
538	.is_visible = gpd_fan_hwmon_is_visible,
539	.read = gpd_fan_hwmon_read,
540	.write = gpd_fan_hwmon_write,
541};
542
543static const struct hwmon_channel_info *gpd_fan_hwmon_channel_info[] = {
544	HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT),
545	HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
546	NULL
547};
548
549static struct hwmon_chip_info gpd_fan_chip_info = {
550	.ops = &gpd_fan_ops,
551	.info = gpd_fan_hwmon_channel_info
552};
553
554static void gpd_win4_init_ec(void)
555{
556	u8 chip_id, chip_ver;
557
558	gpd_ecram_read(0x2000, &chip_id);
559
560	if (chip_id == 0x55) {
561		gpd_ecram_read(0x1060, &chip_ver);
562		gpd_ecram_write(0x1060, chip_ver | 0x80);
563	}
564}
565
566static void gpd_init_ec(void)
567{
568	// The buggy firmware won't initialize EC properly on boot.
569	// Before its initialization, reading RPM will always return 0,
570	// and writing PWM will have no effect.
571	// Initialize it manually on driver load.
572	if (gpd_driver_priv.drvdata->board == win4_6800u)
573		gpd_win4_init_ec();
574}
575
576static int gpd_fan_probe(struct platform_device *pdev)
577{
578	struct device *dev = &pdev->dev;
579	const struct resource *region;
580	const struct resource *res;
581	const struct device *hwdev;
582
583	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
584	if (!res)
585		return dev_err_probe(dev, -EINVAL,
586				     "Failed to get platform resource\n");
587
588	region = devm_request_region(dev, res->start,
589				     resource_size(res), DRIVER_NAME);
590	if (!region)
591		return dev_err_probe(dev, -EBUSY,
592				     "Failed to request region\n");
593
594	hwdev = devm_hwmon_device_register_with_info(dev,
595						     DRIVER_NAME,
596						     NULL,
597						     &gpd_fan_chip_info,
598						     NULL);
599	if (IS_ERR(hwdev))
600		return dev_err_probe(dev, PTR_ERR(hwdev),
601				     "Failed to register hwmon device\n");
602
603	gpd_init_ec();
604
605	return 0;
606}
607
608static void gpd_fan_remove(__always_unused struct platform_device *pdev)
609{
610	gpd_driver_priv.pwm_enable = AUTOMATIC;
611	gpd_set_pwm_enable(AUTOMATIC);
612}
613
614static struct platform_driver gpd_fan_driver = {
615	.probe = gpd_fan_probe,
616	.remove = gpd_fan_remove,
617	.driver = {
618		.name = KBUILD_MODNAME,
619	},
620};
621
622static struct platform_device *gpd_fan_platform_device;
623
624static int __init gpd_fan_init(void)
625{
626	const struct gpd_fan_drvdata *match = NULL;
627
628	for (const struct gpd_fan_drvdata **p = gpd_module_drvdata; *p; p++) {
629		if (strcmp(gpd_fan_board, (*p)->board_name) == 0) {
630			match = *p;
631			break;
632		}
633	}
634
635	if (!match) {
636		const struct dmi_system_id *dmi_match =
637			dmi_first_match(dmi_table);
638		if (dmi_match)
639			match = dmi_match->driver_data;
640	}
641
642	if (!match)
643		return -ENODEV;
644
645	gpd_driver_priv.pwm_enable = AUTOMATIC;
646	gpd_driver_priv.pwm_value = 255;
647	gpd_driver_priv.drvdata = match;
648
649	struct resource gpd_fan_resources[] = {
650		{
651			.start = match->addr_port,
652			.end = match->data_port,
653			.flags = IORESOURCE_IO,
654		},
655	};
656
657	gpd_fan_platform_device = platform_create_bundle(&gpd_fan_driver,
658							 gpd_fan_probe,
659							 gpd_fan_resources,
660							 1, NULL, 0);
661
662	if (IS_ERR(gpd_fan_platform_device)) {
663		pr_warn("Failed to create platform device\n");
664		return PTR_ERR(gpd_fan_platform_device);
665	}
666
667	return 0;
668}
669
670static void __exit gpd_fan_exit(void)
671{
672	platform_device_unregister(gpd_fan_platform_device);
673	platform_driver_unregister(&gpd_fan_driver);
674}
675
676MODULE_DEVICE_TABLE(dmi, dmi_table);
677
678module_init(gpd_fan_init);
679module_exit(gpd_fan_exit);
680
681MODULE_LICENSE("GPL");
682MODULE_AUTHOR("Cryolitia PukNgae <cryolitia@uniontech.com>");
683MODULE_DESCRIPTION("GPD Devices fan control driver");