discrete.c

  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 */
 27static 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 */
 40static const guid_t cio2_sensor_module_guid =
 41	GUID_INIT(0x822ace8f, 0x2814, 0x4174,
 42		  0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee);
 43
 44static 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
 57static 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
 79static 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... */
101static struct gpio_desc *
102skl_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 */
137struct 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
146static 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
169static 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_HOTPLUG_DETECT:
219		*con_id = "hpd";
220		*gpio_flags = GPIO_ACTIVE_HIGH;
221		break;
222	case INT3472_GPIO_TYPE_POWER_ENABLE:
223		*con_id = "avdd";
224		*gpio_flags = GPIO_ACTIVE_HIGH;
225		break;
226	case INT3472_GPIO_TYPE_HANDSHAKE:
227		*con_id = "dvdd";
228		*gpio_flags = GPIO_ACTIVE_HIGH;
229		/* Setups using a handshake pin need 25 ms enable delay */
230		*enable_time_us = 25 * USEC_PER_MSEC;
231		break;
232	default:
233		*con_id = "unknown";
234		*gpio_flags = GPIO_ACTIVE_HIGH;
235		break;
236	}
237}
238
239/**
240 * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
241 * @ares: A pointer to a &struct acpi_resource
242 * @data: A pointer to a &struct int3472_discrete_device
243 *
244 * This function handles GPIO resources that are against an INT3472
245 * ACPI device, by checking the value of the corresponding _DSM entry.
246 * This will return a 32bit int, where the lowest byte represents the
247 * function of the GPIO pin:
248 *
249 * 0x00 Reset
250 * 0x01 Power down
251 * 0x0b Power enable
252 * 0x0c Clock enable
253 * 0x0d Privacy LED
254 * 0x13 Hotplug detect
255 *
256 * There are some known platform specific quirks where that does not quite
257 * hold up; for example where a pin with type 0x01 (Power down) is mapped to
258 * a sensor pin that performs a reset function or entries in _CRS and _DSM that
259 * do not actually correspond to a physical connection. These will be handled
260 * by the mapping sub-functions.
261 *
262 * GPIOs will either be mapped directly to the sensor device or else used
263 * to create clocks and regulators via the usual frameworks.
264 *
265 * Return:
266 * * 1		- Continue the loop without adding a copy of the resource to
267 * *		  the list passed to acpi_dev_get_resources()
268 * * 0		- Continue the loop after adding a copy of the resource to
269 * *		  the list passed to acpi_dev_get_resources()
270 * * -errno	- Error, break loop
271 */
272static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
273					     void *data)
274{
275	struct int3472_discrete_device *int3472 = data;
276	const char *second_sensor = NULL;
277	struct acpi_resource_gpio *agpio;
278	unsigned int enable_time_us;
279	u8 active_value, pin, type;
280	unsigned long gpio_flags;
281	union acpi_object *obj;
282	struct gpio_desc *gpio;
283	const char *err_msg;
284	const char *con_id;
285	int ret;
286
287	if (!acpi_gpio_get_io_resource(ares, &agpio))
288		return 1;
289
290	/*
291	 * ngpios + 2 because the index of this _DSM function is 1-based and
292	 * the first function is just a count.
293	 */
294	obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
295				      &int3472_gpio_guid, 0x00,
296				      int3472->ngpios + 2,
297				      NULL, ACPI_TYPE_INTEGER);
298
299	if (!obj) {
300		dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
301			 agpio->pin_table[0]);
302		return 1;
303	}
304
305	type = FIELD_GET(INT3472_GPIO_DSM_TYPE, obj->integer.value);
306
307	int3472_get_con_id_and_polarity(int3472, &type, &con_id, &gpio_flags, &enable_time_us);
308
309	pin = FIELD_GET(INT3472_GPIO_DSM_PIN, obj->integer.value);
310	/* Pin field is not really used under Windows and wraps around at 8 bits */
311	if (pin != (agpio->pin_table[0] & 0xff))
312		dev_dbg(int3472->dev, FW_BUG "%s %s pin number mismatch _DSM %d resource %d\n",
313			con_id, agpio->resource_source.string_ptr, pin, agpio->pin_table[0]);
314
315	active_value = FIELD_GET(INT3472_GPIO_DSM_SENSOR_ON_VAL, obj->integer.value);
316	if (!active_value)
317		gpio_flags ^= GPIO_ACTIVE_LOW;
318
319	dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", con_id,
320		agpio->resource_source.string_ptr, agpio->pin_table[0],
321		str_high_low(gpio_flags == GPIO_ACTIVE_HIGH));
322
323	switch (type) {
324	case INT3472_GPIO_TYPE_RESET:
325	case INT3472_GPIO_TYPE_POWERDOWN:
326	case INT3472_GPIO_TYPE_HOTPLUG_DETECT:
327		ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, con_id, gpio_flags);
328		if (ret)
329			err_msg = "Failed to map GPIO pin to sensor\n";
330
331		break;
332	case INT3472_GPIO_TYPE_CLK_ENABLE:
333	case INT3472_GPIO_TYPE_PRIVACY_LED:
334	case INT3472_GPIO_TYPE_POWER_ENABLE:
335	case INT3472_GPIO_TYPE_HANDSHAKE:
336		gpio = skl_int3472_gpiod_get_from_temp_lookup(int3472, agpio, con_id, gpio_flags);
337		if (IS_ERR(gpio)) {
338			ret = PTR_ERR(gpio);
339			err_msg = "Failed to get GPIO\n";
340			break;
341		}
342
343		switch (type) {
344		case INT3472_GPIO_TYPE_CLK_ENABLE:
345			ret = skl_int3472_register_gpio_clock(int3472, gpio);
346			if (ret)
347				err_msg = "Failed to register clock\n";
348
349			break;
350		case INT3472_GPIO_TYPE_PRIVACY_LED:
351			ret = skl_int3472_register_pled(int3472, gpio);
352			if (ret)
353				err_msg = "Failed to register LED\n";
354
355			break;
356		case INT3472_GPIO_TYPE_POWER_ENABLE:
357			second_sensor = int3472->quirks.avdd_second_sensor;
358			fallthrough;
359		case INT3472_GPIO_TYPE_HANDSHAKE:
360			ret = skl_int3472_register_regulator(int3472, gpio, enable_time_us,
361							     con_id, second_sensor);
362			if (ret)
363				err_msg = "Failed to register regulator\n";
364
365			break;
366		default: /* Never reached */
367			ret = -EINVAL;
368			break;
369		}
370
371		if (ret)
372			gpiod_put(gpio);
373
374		break;
375	default:
376		dev_warn(int3472->dev,
377			 "GPIO type 0x%02x unknown; the sensor may not work\n",
378			 type);
379		ret = 1;
380		break;
381	}
382
383	int3472->ngpios++;
384	ACPI_FREE(obj);
385
386	if (ret < 0)
387		return dev_err_probe(int3472->dev, ret, err_msg);
388
389	/* Tell acpi_dev_get_resources() to not make a copy of the resource */
390	return 1;
391}
392
393int int3472_discrete_parse_crs(struct int3472_discrete_device *int3472)
394{
395	LIST_HEAD(resource_list);
396	int ret;
397
398	skl_int3472_log_sensor_module_name(int3472);
399
400	ret = acpi_dev_get_resources(int3472->adev, &resource_list,
401				     skl_int3472_handle_gpio_resources,
402				     int3472);
403	if (ret < 0)
404		return ret;
405
406	acpi_dev_free_resource_list(&resource_list);
407
408	/* Register _DSM based clock (no-op if a GPIO clock was already registered) */
409	ret = skl_int3472_register_dsm_clock(int3472);
410	if (ret < 0)
411		return ret;
412
413	int3472->gpios.dev_id = int3472->sensor_name;
414	gpiod_add_lookup_table(&int3472->gpios);
415
416	return 0;
417}
418EXPORT_SYMBOL_NS_GPL(int3472_discrete_parse_crs, "INTEL_INT3472_DISCRETE");
419
420void int3472_discrete_cleanup(struct int3472_discrete_device *int3472)
421{
422	gpiod_remove_lookup_table(&int3472->gpios);
423
424	skl_int3472_unregister_clock(int3472);
425	skl_int3472_unregister_pled(int3472);
426	skl_int3472_unregister_regulator(int3472);
427}
428EXPORT_SYMBOL_NS_GPL(int3472_discrete_cleanup, "INTEL_INT3472_DISCRETE");
429
430static void skl_int3472_discrete_remove(struct platform_device *pdev)
431{
432	int3472_discrete_cleanup(platform_get_drvdata(pdev));
433}
434
435static int skl_int3472_discrete_probe(struct platform_device *pdev)
436{
437	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
438	const struct int3472_discrete_quirks *quirks = NULL;
439	struct int3472_discrete_device *int3472;
440	const struct dmi_system_id *id;
441	struct int3472_cldb cldb;
442	int ret;
443
444	if (!adev)
445		return -ENODEV;
446
447	id = dmi_first_match(skl_int3472_discrete_quirks);
448	if (id)
449		quirks = id->driver_data;
450
451	ret = skl_int3472_fill_cldb(adev, &cldb);
452	if (ret) {
453		dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
454		return ret;
455	}
456
457	if (cldb.control_logic_type != 1) {
458		dev_err(&pdev->dev, "Unsupported control logic type %u\n",
459			cldb.control_logic_type);
460		return -EINVAL;
461	}
462
463	/* Max num GPIOs we've seen plus a terminator */
464	int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
465			       INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
466	if (!int3472)
467		return -ENOMEM;
468
469	int3472->adev = adev;
470	int3472->dev = &pdev->dev;
471	platform_set_drvdata(pdev, int3472);
472	int3472->clock.imgclk_index = cldb.clock_source;
473
474	if (quirks)
475		int3472->quirks = *quirks;
476
477	ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
478						   &int3472->sensor_name);
479	if (ret)
480		return ret;
481
482	/*
483	 * Initialising this list means we can call gpiod_remove_lookup_table()
484	 * in failure paths without issue.
485	 */
486	INIT_LIST_HEAD(&int3472->gpios.list);
487
488	ret = int3472_discrete_parse_crs(int3472);
489	if (ret) {
490		skl_int3472_discrete_remove(pdev);
491		return ret;
492	}
493
494	acpi_dev_clear_dependencies(adev);
495	return 0;
496}
497
498static const struct acpi_device_id int3472_device_id[] = {
499	{ "INT3472", 0 },
500	{ }
501};
502MODULE_DEVICE_TABLE(acpi, int3472_device_id);
503
504static struct platform_driver int3472_discrete = {
505	.driver = {
506		.name = "int3472-discrete",
507		.acpi_match_table = int3472_device_id,
508	},
509	.probe = skl_int3472_discrete_probe,
510	.remove = skl_int3472_discrete_remove,
511};
512module_platform_driver(int3472_discrete);
513
514MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
515MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
516MODULE_LICENSE("GPL v2");
517MODULE_IMPORT_NS("INTEL_INT3472");