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/gpio/consumer.h>
9 #include <linux/gpio/machine.h>
10 #include <linux/i2c.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/overflow.h>
14 #include <linux/platform_device.h>
15 #include <linux/string_choices.h>
16 #include <linux/uuid.h>
17
18 #include "common.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
skl_int3472_log_sensor_module_name(struct int3472_discrete_device * int3472)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
skl_int3472_fill_gpiod_lookup(struct gpiod_lookup * table_entry,struct acpi_resource_gpio * agpio,const char * func,unsigned long gpio_flags)57 static int skl_int3472_fill_gpiod_lookup(struct gpiod_lookup *table_entry,
58 struct acpi_resource_gpio *agpio,
59 const char *func, 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], func, gpio_flags);
75
76 return 0;
77 }
78
skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio,const char * func,unsigned long gpio_flags)79 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
80 struct acpi_resource_gpio *agpio,
81 const char *func, 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, func, 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 *
skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio,const char * func,unsigned long gpio_flags)102 skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device *int3472,
103 struct acpi_resource_gpio *agpio,
104 const char *func, 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, func, gpio_flags);
116 if (ret)
117 return ERR_PTR(ret);
118
119 gpiod_add_lookup_table(lookup);
120 desc = devm_gpiod_get(int3472->dev, func, 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 * @func: The function, e.g. "enable"
133 * @polarity_low: GPIO_ACTIVE_LOW true if the @polarity_low is true,
134 * GPIO_ACTIVE_HIGH otherwise
135 */
136 struct int3472_gpio_map {
137 const char *hid;
138 u8 type_from;
139 u8 type_to;
140 bool polarity_low;
141 const char *func;
142 };
143
144 static const struct int3472_gpio_map int3472_gpio_map[] = {
145 { "INT347E", INT3472_GPIO_TYPE_RESET, INT3472_GPIO_TYPE_RESET, false, "enable" },
146 };
147
int3472_get_func_and_polarity(struct acpi_device * adev,u8 * type,const char ** func,unsigned long * gpio_flags)148 static void int3472_get_func_and_polarity(struct acpi_device *adev, u8 *type,
149 const char **func, unsigned long *gpio_flags)
150 {
151 unsigned int i;
152
153 for (i = 0; i < ARRAY_SIZE(int3472_gpio_map); i++) {
154 /*
155 * Map the firmware-provided GPIO to whatever a driver expects
156 * (as in DT bindings). First check if the type matches with the
157 * GPIO map, then further check that the device _HID matches.
158 */
159 if (*type != int3472_gpio_map[i].type_from)
160 continue;
161
162 if (!acpi_dev_hid_uid_match(adev, int3472_gpio_map[i].hid, NULL))
163 continue;
164
165 *type = int3472_gpio_map[i].type_to;
166 *gpio_flags = int3472_gpio_map[i].polarity_low ?
167 GPIO_ACTIVE_LOW : GPIO_ACTIVE_HIGH;
168 *func = int3472_gpio_map[i].func;
169 return;
170 }
171
172 switch (*type) {
173 case INT3472_GPIO_TYPE_RESET:
174 *func = "reset";
175 *gpio_flags = GPIO_ACTIVE_LOW;
176 break;
177 case INT3472_GPIO_TYPE_POWERDOWN:
178 *func = "powerdown";
179 *gpio_flags = GPIO_ACTIVE_LOW;
180 break;
181 case INT3472_GPIO_TYPE_CLK_ENABLE:
182 *func = "clk-enable";
183 *gpio_flags = GPIO_ACTIVE_HIGH;
184 break;
185 case INT3472_GPIO_TYPE_PRIVACY_LED:
186 *func = "privacy-led";
187 *gpio_flags = GPIO_ACTIVE_HIGH;
188 break;
189 case INT3472_GPIO_TYPE_POWER_ENABLE:
190 *func = "power-enable";
191 *gpio_flags = GPIO_ACTIVE_HIGH;
192 break;
193 default:
194 *func = "unknown";
195 *gpio_flags = GPIO_ACTIVE_HIGH;
196 break;
197 }
198 }
199
200 /**
201 * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
202 * @ares: A pointer to a &struct acpi_resource
203 * @data: A pointer to a &struct int3472_discrete_device
204 *
205 * This function handles GPIO resources that are against an INT3472
206 * ACPI device, by checking the value of the corresponding _DSM entry.
207 * This will return a 32bit int, where the lowest byte represents the
208 * function of the GPIO pin:
209 *
210 * 0x00 Reset
211 * 0x01 Power down
212 * 0x0b Power enable
213 * 0x0c Clock enable
214 * 0x0d Privacy LED
215 *
216 * There are some known platform specific quirks where that does not quite
217 * hold up; for example where a pin with type 0x01 (Power down) is mapped to
218 * a sensor pin that performs a reset function or entries in _CRS and _DSM that
219 * do not actually correspond to a physical connection. These will be handled
220 * by the mapping sub-functions.
221 *
222 * GPIOs will either be mapped directly to the sensor device or else used
223 * to create clocks and regulators via the usual frameworks.
224 *
225 * Return:
226 * * 1 - Continue the loop without adding a copy of the resource to
227 * * the list passed to acpi_dev_get_resources()
228 * * 0 - Continue the loop after adding a copy of the resource to
229 * * the list passed to acpi_dev_get_resources()
230 * * -errno - Error, break loop
231 */
skl_int3472_handle_gpio_resources(struct acpi_resource * ares,void * data)232 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
233 void *data)
234 {
235 struct int3472_discrete_device *int3472 = data;
236 struct acpi_resource_gpio *agpio;
237 u8 active_value, pin, type;
238 union acpi_object *obj;
239 struct gpio_desc *gpio;
240 const char *err_msg;
241 const char *func;
242 unsigned long gpio_flags;
243 int ret;
244
245 if (!acpi_gpio_get_io_resource(ares, &agpio))
246 return 1;
247
248 /*
249 * ngpios + 2 because the index of this _DSM function is 1-based and
250 * the first function is just a count.
251 */
252 obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
253 &int3472_gpio_guid, 0x00,
254 int3472->ngpios + 2,
255 NULL, ACPI_TYPE_INTEGER);
256
257 if (!obj) {
258 dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
259 agpio->pin_table[0]);
260 return 1;
261 }
262
263 type = FIELD_GET(INT3472_GPIO_DSM_TYPE, obj->integer.value);
264
265 int3472_get_func_and_polarity(int3472->sensor, &type, &func, &gpio_flags);
266
267 pin = FIELD_GET(INT3472_GPIO_DSM_PIN, obj->integer.value);
268 /* Pin field is not really used under Windows and wraps around at 8 bits */
269 if (pin != (agpio->pin_table[0] & 0xff))
270 dev_dbg(int3472->dev, FW_BUG "%s %s pin number mismatch _DSM %d resource %d\n",
271 func, agpio->resource_source.string_ptr, pin, agpio->pin_table[0]);
272
273 active_value = FIELD_GET(INT3472_GPIO_DSM_SENSOR_ON_VAL, obj->integer.value);
274 if (!active_value)
275 gpio_flags ^= GPIO_ACTIVE_LOW;
276
277 dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", func,
278 agpio->resource_source.string_ptr, agpio->pin_table[0],
279 str_high_low(gpio_flags == GPIO_ACTIVE_HIGH));
280
281 switch (type) {
282 case INT3472_GPIO_TYPE_RESET:
283 case INT3472_GPIO_TYPE_POWERDOWN:
284 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, gpio_flags);
285 if (ret)
286 err_msg = "Failed to map GPIO pin to sensor\n";
287
288 break;
289 case INT3472_GPIO_TYPE_CLK_ENABLE:
290 case INT3472_GPIO_TYPE_PRIVACY_LED:
291 case INT3472_GPIO_TYPE_POWER_ENABLE:
292 gpio = skl_int3472_gpiod_get_from_temp_lookup(int3472, agpio, func, gpio_flags);
293 if (IS_ERR(gpio)) {
294 ret = PTR_ERR(gpio);
295 err_msg = "Failed to get GPIO\n";
296 break;
297 }
298
299 switch (type) {
300 case INT3472_GPIO_TYPE_CLK_ENABLE:
301 ret = skl_int3472_register_gpio_clock(int3472, gpio);
302 if (ret)
303 err_msg = "Failed to register clock\n";
304
305 break;
306 case INT3472_GPIO_TYPE_PRIVACY_LED:
307 ret = skl_int3472_register_pled(int3472, gpio);
308 if (ret)
309 err_msg = "Failed to register LED\n";
310
311 break;
312 case INT3472_GPIO_TYPE_POWER_ENABLE:
313 ret = skl_int3472_register_regulator(int3472, gpio);
314 if (ret)
315 err_msg = "Failed to map regulator to sensor\n";
316
317 break;
318 default: /* Never reached */
319 ret = -EINVAL;
320 break;
321 }
322 break;
323 default:
324 dev_warn(int3472->dev,
325 "GPIO type 0x%02x unknown; the sensor may not work\n",
326 type);
327 ret = 1;
328 break;
329 }
330
331 int3472->ngpios++;
332 ACPI_FREE(obj);
333
334 if (ret < 0)
335 return dev_err_probe(int3472->dev, ret, err_msg);
336
337 /* Tell acpi_dev_get_resources() to not make a copy of the resource */
338 return 1;
339 }
340
skl_int3472_parse_crs(struct int3472_discrete_device * int3472)341 static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
342 {
343 LIST_HEAD(resource_list);
344 int ret;
345
346 skl_int3472_log_sensor_module_name(int3472);
347
348 ret = acpi_dev_get_resources(int3472->adev, &resource_list,
349 skl_int3472_handle_gpio_resources,
350 int3472);
351 if (ret < 0)
352 return ret;
353
354 acpi_dev_free_resource_list(&resource_list);
355
356 /* Register _DSM based clock (no-op if a GPIO clock was already registered) */
357 ret = skl_int3472_register_dsm_clock(int3472);
358 if (ret < 0)
359 return ret;
360
361 int3472->gpios.dev_id = int3472->sensor_name;
362 gpiod_add_lookup_table(&int3472->gpios);
363
364 return 0;
365 }
366
skl_int3472_discrete_remove(struct platform_device * pdev)367 static void skl_int3472_discrete_remove(struct platform_device *pdev)
368 {
369 struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev);
370
371 gpiod_remove_lookup_table(&int3472->gpios);
372
373 skl_int3472_unregister_clock(int3472);
374 skl_int3472_unregister_pled(int3472);
375 skl_int3472_unregister_regulator(int3472);
376 }
377
skl_int3472_discrete_probe(struct platform_device * pdev)378 static int skl_int3472_discrete_probe(struct platform_device *pdev)
379 {
380 struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
381 struct int3472_discrete_device *int3472;
382 struct int3472_cldb cldb;
383 int ret;
384
385 if (!adev)
386 return -ENODEV;
387
388 ret = skl_int3472_fill_cldb(adev, &cldb);
389 if (ret) {
390 dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
391 return ret;
392 }
393
394 if (cldb.control_logic_type != 1) {
395 dev_err(&pdev->dev, "Unsupported control logic type %u\n",
396 cldb.control_logic_type);
397 return -EINVAL;
398 }
399
400 /* Max num GPIOs we've seen plus a terminator */
401 int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
402 INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
403 if (!int3472)
404 return -ENOMEM;
405
406 int3472->adev = adev;
407 int3472->dev = &pdev->dev;
408 platform_set_drvdata(pdev, int3472);
409 int3472->clock.imgclk_index = cldb.clock_source;
410
411 ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
412 &int3472->sensor_name);
413 if (ret)
414 return ret;
415
416 /*
417 * Initialising this list means we can call gpiod_remove_lookup_table()
418 * in failure paths without issue.
419 */
420 INIT_LIST_HEAD(&int3472->gpios.list);
421
422 ret = skl_int3472_parse_crs(int3472);
423 if (ret) {
424 skl_int3472_discrete_remove(pdev);
425 return ret;
426 }
427
428 acpi_dev_clear_dependencies(adev);
429 return 0;
430 }
431
432 static const struct acpi_device_id int3472_device_id[] = {
433 { "INT3472", 0 },
434 { }
435 };
436 MODULE_DEVICE_TABLE(acpi, int3472_device_id);
437
438 static struct platform_driver int3472_discrete = {
439 .driver = {
440 .name = "int3472-discrete",
441 .acpi_match_table = int3472_device_id,
442 },
443 .probe = skl_int3472_discrete_probe,
444 .remove = skl_int3472_discrete_remove,
445 };
446 module_platform_driver(int3472_discrete);
447
448 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
449 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
450 MODULE_LICENSE("GPL v2");
451