xref: /linux/drivers/platform/x86/intel/int3472/discrete.c (revision 6d47b4f08436cb682fb2644e6265a3897fd42a77)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Author: Dan Scally <djrscally@gmail.com> */
3 
4 #include <linux/acpi.h>
5 #include <linux/array_size.h>
6 #include <linux/bitfield.h>
7 #include <linux/device.h>
8 #include <linux/dmi.h>
9 #include <linux/gpio/consumer.h>
10 #include <linux/gpio/machine.h>
11 #include <linux/i2c.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/overflow.h>
15 #include <linux/platform_data/x86/int3472.h>
16 #include <linux/platform_device.h>
17 #include <linux/string_choices.h>
18 #include <linux/uuid.h>
19 
20 /*
21  * 79234640-9e10-4fea-a5c1-b5aa8b19756f
22  * This _DSM GUID returns information about the GPIO lines mapped to a
23  * discrete INT3472 device. Function number 1 returns a count of the GPIO
24  * lines that are mapped. Subsequent functions return 32 bit ints encoding
25  * information about the GPIO line, including its purpose.
26  */
27 static const guid_t int3472_gpio_guid =
28 	GUID_INIT(0x79234640, 0x9e10, 0x4fea,
29 		  0xa5, 0xc1, 0xb5, 0xaa, 0x8b, 0x19, 0x75, 0x6f);
30 
31 #define INT3472_GPIO_DSM_TYPE				GENMASK(7, 0)
32 #define INT3472_GPIO_DSM_PIN				GENMASK(15, 8)
33 #define INT3472_GPIO_DSM_SENSOR_ON_VAL			GENMASK(31, 24)
34 
35 /*
36  * 822ace8f-2814-4174-a56b-5f029fe079ee
37  * This _DSM GUID returns a string from the sensor device, which acts as a
38  * module identifier.
39  */
40 static const guid_t cio2_sensor_module_guid =
41 	GUID_INIT(0x822ace8f, 0x2814, 0x4174,
42 		  0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee);
43 
44 static void skl_int3472_log_sensor_module_name(struct int3472_discrete_device *int3472)
45 {
46 	union acpi_object *obj;
47 
48 	obj = acpi_evaluate_dsm_typed(int3472->sensor->handle,
49 				      &cio2_sensor_module_guid, 0x00,
50 				      0x01, NULL, ACPI_TYPE_STRING);
51 	if (obj) {
52 		dev_dbg(int3472->dev, "Sensor module id: '%s'\n", obj->string.pointer);
53 		ACPI_FREE(obj);
54 	}
55 }
56 
57 static int skl_int3472_fill_gpiod_lookup(struct gpiod_lookup *table_entry,
58 					 struct acpi_resource_gpio *agpio,
59 					 const char *con_id, unsigned long gpio_flags)
60 {
61 	char *path = agpio->resource_source.string_ptr;
62 	struct acpi_device *adev;
63 	acpi_handle handle;
64 	acpi_status status;
65 
66 	status = acpi_get_handle(NULL, path, &handle);
67 	if (ACPI_FAILURE(status))
68 		return -EINVAL;
69 
70 	adev = acpi_fetch_acpi_dev(handle);
71 	if (!adev)
72 		return -ENODEV;
73 
74 	*table_entry = GPIO_LOOKUP(acpi_dev_name(adev), agpio->pin_table[0], con_id, gpio_flags);
75 
76 	return 0;
77 }
78 
79 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
80 					  struct acpi_resource_gpio *agpio,
81 					  const char *con_id, unsigned long gpio_flags)
82 {
83 	int ret;
84 
85 	if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) {
86 		dev_warn(int3472->dev, "Too many GPIOs mapped\n");
87 		return -EINVAL;
88 	}
89 
90 	ret = skl_int3472_fill_gpiod_lookup(&int3472->gpios.table[int3472->n_sensor_gpios],
91 					    agpio, con_id, gpio_flags);
92 	if (ret)
93 		return ret;
94 
95 	int3472->n_sensor_gpios++;
96 
97 	return 0;
98 }
99 
100 /* This should *really* only be used when there's no other way... */
101 static struct gpio_desc *
102 skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device *int3472,
103 				       struct acpi_resource_gpio *agpio,
104 				       const char *con_id, unsigned long gpio_flags)
105 {
106 	struct gpio_desc *desc;
107 	int ret;
108 
109 	struct gpiod_lookup_table *lookup __free(kfree) =
110 			kzalloc(struct_size(lookup, table, 2), GFP_KERNEL);
111 	if (!lookup)
112 		return ERR_PTR(-ENOMEM);
113 
114 	lookup->dev_id = dev_name(int3472->dev);
115 	ret = skl_int3472_fill_gpiod_lookup(&lookup->table[0], agpio, con_id, gpio_flags);
116 	if (ret)
117 		return ERR_PTR(ret);
118 
119 	gpiod_add_lookup_table(lookup);
120 	desc = gpiod_get(int3472->dev, con_id, GPIOD_OUT_LOW);
121 	gpiod_remove_lookup_table(lookup);
122 
123 	return desc;
124 }
125 
126 /**
127  * struct int3472_gpio_map - Map GPIOs to whatever is expected by the
128  * sensor driver (as in DT bindings)
129  * @hid: The ACPI HID of the device without the instance number e.g. INT347E
130  * @type_from: The GPIO type from ACPI ?SDT
131  * @type_to: The assigned GPIO type, typically same as @type_from
132  * @enable_time_us: Enable time in usec for GPIOs mapped to regulators
133  * @con_id: The name of the GPIO for the device
134  * @polarity_low: GPIO_ACTIVE_LOW true if the @polarity_low is true,
135  * GPIO_ACTIVE_HIGH otherwise
136  */
137 struct int3472_gpio_map {
138 	const char *hid;
139 	u8 type_from;
140 	u8 type_to;
141 	bool polarity_low;
142 	unsigned int enable_time_us;
143 	const char *con_id;
144 };
145 
146 static const struct int3472_gpio_map int3472_gpio_map[] = {
147 	{	/* mt9m114 designs declare a powerdown pin which controls the regulators */
148 		.hid = "INT33F0",
149 		.type_from = INT3472_GPIO_TYPE_POWERDOWN,
150 		.type_to = INT3472_GPIO_TYPE_POWER_ENABLE,
151 		.con_id = "vdd",
152 		.enable_time_us = GPIO_REGULATOR_ENABLE_TIME,
153 	},
154 	{	/* ov7251 driver / DT-bindings expect "enable" as con_id for reset */
155 		.hid = "INT347E",
156 		.type_from = INT3472_GPIO_TYPE_RESET,
157 		.type_to = INT3472_GPIO_TYPE_RESET,
158 		.con_id = "enable",
159 	},
160 	{	/* ov08x40's handshake pin needs a 45 ms delay on some HP laptops */
161 		.hid = "OVTI08F4",
162 		.type_from = INT3472_GPIO_TYPE_HANDSHAKE,
163 		.type_to = INT3472_GPIO_TYPE_HANDSHAKE,
164 		.con_id = "dvdd",
165 		.enable_time_us = 45 * USEC_PER_MSEC,
166 	},
167 };
168 
169 static void int3472_get_con_id_and_polarity(struct int3472_discrete_device *int3472, u8 *type,
170 					    const char **con_id, unsigned long *gpio_flags,
171 					    unsigned int *enable_time_us)
172 {
173 	struct acpi_device *adev = int3472->sensor;
174 	unsigned int i;
175 
176 	for (i = 0; i < ARRAY_SIZE(int3472_gpio_map); i++) {
177 		/*
178 		 * Map the firmware-provided GPIO to whatever a driver expects
179 		 * (as in DT bindings). First check if the type matches with the
180 		 * GPIO map, then further check that the device _HID matches.
181 		 */
182 		if (*type != int3472_gpio_map[i].type_from)
183 			continue;
184 
185 		if (!acpi_dev_hid_uid_match(adev, int3472_gpio_map[i].hid, NULL))
186 			continue;
187 
188 		dev_dbg(int3472->dev, "mapping type 0x%02x pin to 0x%02x %s\n",
189 			*type, int3472_gpio_map[i].type_to, int3472_gpio_map[i].con_id);
190 
191 		*type = int3472_gpio_map[i].type_to;
192 		*gpio_flags = int3472_gpio_map[i].polarity_low ?
193 			      GPIO_ACTIVE_LOW : GPIO_ACTIVE_HIGH;
194 		*con_id = int3472_gpio_map[i].con_id;
195 		*enable_time_us = int3472_gpio_map[i].enable_time_us;
196 		return;
197 	}
198 
199 	*enable_time_us = GPIO_REGULATOR_ENABLE_TIME;
200 
201 	switch (*type) {
202 	case INT3472_GPIO_TYPE_RESET:
203 		*con_id = "reset";
204 		*gpio_flags = GPIO_ACTIVE_LOW;
205 		break;
206 	case INT3472_GPIO_TYPE_POWERDOWN:
207 		*con_id = "powerdown";
208 		*gpio_flags = GPIO_ACTIVE_LOW;
209 		break;
210 	case INT3472_GPIO_TYPE_CLK_ENABLE:
211 		*con_id = "clk-enable";
212 		*gpio_flags = GPIO_ACTIVE_HIGH;
213 		break;
214 	case INT3472_GPIO_TYPE_PRIVACY_LED:
215 		*con_id = "privacy-led";
216 		*gpio_flags = GPIO_ACTIVE_HIGH;
217 		break;
218 	case INT3472_GPIO_TYPE_POWER_ENABLE:
219 		*con_id = "avdd";
220 		*gpio_flags = GPIO_ACTIVE_HIGH;
221 		break;
222 	case INT3472_GPIO_TYPE_HANDSHAKE:
223 		*con_id = "dvdd";
224 		*gpio_flags = GPIO_ACTIVE_HIGH;
225 		/* Setups using a handshake pin need 25 ms enable delay */
226 		*enable_time_us = 25 * USEC_PER_MSEC;
227 		break;
228 	default:
229 		*con_id = "unknown";
230 		*gpio_flags = GPIO_ACTIVE_HIGH;
231 		break;
232 	}
233 }
234 
235 /**
236  * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
237  * @ares: A pointer to a &struct acpi_resource
238  * @data: A pointer to a &struct int3472_discrete_device
239  *
240  * This function handles GPIO resources that are against an INT3472
241  * ACPI device, by checking the value of the corresponding _DSM entry.
242  * This will return a 32bit int, where the lowest byte represents the
243  * function of the GPIO pin:
244  *
245  * 0x00 Reset
246  * 0x01 Power down
247  * 0x0b Power enable
248  * 0x0c Clock enable
249  * 0x0d Privacy LED
250  *
251  * There are some known platform specific quirks where that does not quite
252  * hold up; for example where a pin with type 0x01 (Power down) is mapped to
253  * a sensor pin that performs a reset function or entries in _CRS and _DSM that
254  * do not actually correspond to a physical connection. These will be handled
255  * by the mapping sub-functions.
256  *
257  * GPIOs will either be mapped directly to the sensor device or else used
258  * to create clocks and regulators via the usual frameworks.
259  *
260  * Return:
261  * * 1		- Continue the loop without adding a copy of the resource to
262  * *		  the list passed to acpi_dev_get_resources()
263  * * 0		- Continue the loop after adding a copy of the resource to
264  * *		  the list passed to acpi_dev_get_resources()
265  * * -errno	- Error, break loop
266  */
267 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
268 					     void *data)
269 {
270 	struct int3472_discrete_device *int3472 = data;
271 	const char *second_sensor = NULL;
272 	struct acpi_resource_gpio *agpio;
273 	unsigned int enable_time_us;
274 	u8 active_value, pin, type;
275 	unsigned long gpio_flags;
276 	union acpi_object *obj;
277 	struct gpio_desc *gpio;
278 	const char *err_msg;
279 	const char *con_id;
280 	int ret;
281 
282 	if (!acpi_gpio_get_io_resource(ares, &agpio))
283 		return 1;
284 
285 	/*
286 	 * ngpios + 2 because the index of this _DSM function is 1-based and
287 	 * the first function is just a count.
288 	 */
289 	obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
290 				      &int3472_gpio_guid, 0x00,
291 				      int3472->ngpios + 2,
292 				      NULL, ACPI_TYPE_INTEGER);
293 
294 	if (!obj) {
295 		dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
296 			 agpio->pin_table[0]);
297 		return 1;
298 	}
299 
300 	type = FIELD_GET(INT3472_GPIO_DSM_TYPE, obj->integer.value);
301 
302 	int3472_get_con_id_and_polarity(int3472, &type, &con_id, &gpio_flags, &enable_time_us);
303 
304 	pin = FIELD_GET(INT3472_GPIO_DSM_PIN, obj->integer.value);
305 	/* Pin field is not really used under Windows and wraps around at 8 bits */
306 	if (pin != (agpio->pin_table[0] & 0xff))
307 		dev_dbg(int3472->dev, FW_BUG "%s %s pin number mismatch _DSM %d resource %d\n",
308 			con_id, agpio->resource_source.string_ptr, pin, agpio->pin_table[0]);
309 
310 	active_value = FIELD_GET(INT3472_GPIO_DSM_SENSOR_ON_VAL, obj->integer.value);
311 	if (!active_value)
312 		gpio_flags ^= GPIO_ACTIVE_LOW;
313 
314 	dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", con_id,
315 		agpio->resource_source.string_ptr, agpio->pin_table[0],
316 		str_high_low(gpio_flags == GPIO_ACTIVE_HIGH));
317 
318 	switch (type) {
319 	case INT3472_GPIO_TYPE_RESET:
320 	case INT3472_GPIO_TYPE_POWERDOWN:
321 		ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, con_id, gpio_flags);
322 		if (ret)
323 			err_msg = "Failed to map GPIO pin to sensor\n";
324 
325 		break;
326 	case INT3472_GPIO_TYPE_CLK_ENABLE:
327 	case INT3472_GPIO_TYPE_PRIVACY_LED:
328 	case INT3472_GPIO_TYPE_POWER_ENABLE:
329 	case INT3472_GPIO_TYPE_HANDSHAKE:
330 		gpio = skl_int3472_gpiod_get_from_temp_lookup(int3472, agpio, con_id, gpio_flags);
331 		if (IS_ERR(gpio)) {
332 			ret = PTR_ERR(gpio);
333 			err_msg = "Failed to get GPIO\n";
334 			break;
335 		}
336 
337 		switch (type) {
338 		case INT3472_GPIO_TYPE_CLK_ENABLE:
339 			ret = skl_int3472_register_gpio_clock(int3472, gpio);
340 			if (ret)
341 				err_msg = "Failed to register clock\n";
342 
343 			break;
344 		case INT3472_GPIO_TYPE_PRIVACY_LED:
345 			ret = skl_int3472_register_pled(int3472, gpio);
346 			if (ret)
347 				err_msg = "Failed to register LED\n";
348 
349 			break;
350 		case INT3472_GPIO_TYPE_POWER_ENABLE:
351 			second_sensor = int3472->quirks.avdd_second_sensor;
352 			fallthrough;
353 		case INT3472_GPIO_TYPE_HANDSHAKE:
354 			ret = skl_int3472_register_regulator(int3472, gpio, enable_time_us,
355 							     con_id, second_sensor);
356 			if (ret)
357 				err_msg = "Failed to register regulator\n";
358 
359 			break;
360 		default: /* Never reached */
361 			ret = -EINVAL;
362 			break;
363 		}
364 
365 		if (ret)
366 			gpiod_put(gpio);
367 
368 		break;
369 	default:
370 		dev_warn(int3472->dev,
371 			 "GPIO type 0x%02x unknown; the sensor may not work\n",
372 			 type);
373 		ret = 1;
374 		break;
375 	}
376 
377 	int3472->ngpios++;
378 	ACPI_FREE(obj);
379 
380 	if (ret < 0)
381 		return dev_err_probe(int3472->dev, ret, err_msg);
382 
383 	/* Tell acpi_dev_get_resources() to not make a copy of the resource */
384 	return 1;
385 }
386 
387 int int3472_discrete_parse_crs(struct int3472_discrete_device *int3472)
388 {
389 	LIST_HEAD(resource_list);
390 	int ret;
391 
392 	skl_int3472_log_sensor_module_name(int3472);
393 
394 	ret = acpi_dev_get_resources(int3472->adev, &resource_list,
395 				     skl_int3472_handle_gpio_resources,
396 				     int3472);
397 	if (ret < 0)
398 		return ret;
399 
400 	acpi_dev_free_resource_list(&resource_list);
401 
402 	/* Register _DSM based clock (no-op if a GPIO clock was already registered) */
403 	ret = skl_int3472_register_dsm_clock(int3472);
404 	if (ret < 0)
405 		return ret;
406 
407 	int3472->gpios.dev_id = int3472->sensor_name;
408 	gpiod_add_lookup_table(&int3472->gpios);
409 
410 	return 0;
411 }
412 EXPORT_SYMBOL_NS_GPL(int3472_discrete_parse_crs, "INTEL_INT3472_DISCRETE");
413 
414 void int3472_discrete_cleanup(struct int3472_discrete_device *int3472)
415 {
416 	gpiod_remove_lookup_table(&int3472->gpios);
417 
418 	skl_int3472_unregister_clock(int3472);
419 	skl_int3472_unregister_pled(int3472);
420 	skl_int3472_unregister_regulator(int3472);
421 }
422 EXPORT_SYMBOL_NS_GPL(int3472_discrete_cleanup, "INTEL_INT3472_DISCRETE");
423 
424 static void skl_int3472_discrete_remove(struct platform_device *pdev)
425 {
426 	int3472_discrete_cleanup(platform_get_drvdata(pdev));
427 }
428 
429 static int skl_int3472_discrete_probe(struct platform_device *pdev)
430 {
431 	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
432 	const struct int3472_discrete_quirks *quirks = NULL;
433 	struct int3472_discrete_device *int3472;
434 	const struct dmi_system_id *id;
435 	struct int3472_cldb cldb;
436 	int ret;
437 
438 	if (!adev)
439 		return -ENODEV;
440 
441 	id = dmi_first_match(skl_int3472_discrete_quirks);
442 	if (id)
443 		quirks = id->driver_data;
444 
445 	ret = skl_int3472_fill_cldb(adev, &cldb);
446 	if (ret) {
447 		dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
448 		return ret;
449 	}
450 
451 	if (cldb.control_logic_type != 1) {
452 		dev_err(&pdev->dev, "Unsupported control logic type %u\n",
453 			cldb.control_logic_type);
454 		return -EINVAL;
455 	}
456 
457 	/* Max num GPIOs we've seen plus a terminator */
458 	int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
459 			       INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
460 	if (!int3472)
461 		return -ENOMEM;
462 
463 	int3472->adev = adev;
464 	int3472->dev = &pdev->dev;
465 	platform_set_drvdata(pdev, int3472);
466 	int3472->clock.imgclk_index = cldb.clock_source;
467 
468 	if (quirks)
469 		int3472->quirks = *quirks;
470 
471 	ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
472 						   &int3472->sensor_name);
473 	if (ret)
474 		return ret;
475 
476 	/*
477 	 * Initialising this list means we can call gpiod_remove_lookup_table()
478 	 * in failure paths without issue.
479 	 */
480 	INIT_LIST_HEAD(&int3472->gpios.list);
481 
482 	ret = int3472_discrete_parse_crs(int3472);
483 	if (ret) {
484 		skl_int3472_discrete_remove(pdev);
485 		return ret;
486 	}
487 
488 	acpi_dev_clear_dependencies(adev);
489 	return 0;
490 }
491 
492 static const struct acpi_device_id int3472_device_id[] = {
493 	{ "INT3472", 0 },
494 	{ }
495 };
496 MODULE_DEVICE_TABLE(acpi, int3472_device_id);
497 
498 static struct platform_driver int3472_discrete = {
499 	.driver = {
500 		.name = "int3472-discrete",
501 		.acpi_match_table = int3472_device_id,
502 	},
503 	.probe = skl_int3472_discrete_probe,
504 	.remove = skl_int3472_discrete_remove,
505 };
506 module_platform_driver(int3472_discrete);
507 
508 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
509 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
510 MODULE_LICENSE("GPL v2");
511 MODULE_IMPORT_NS("INTEL_INT3472");
512