1 // SPDX-License-Identifier: GPL-2.0
2 /* Author: Dan Scally <djrscally@gmail.com> */
3
4 #include <linux/acpi.h>
5 #include <linux/clkdev.h>
6 #include <linux/clk-provider.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/uuid.h>
16
17 #include "common.h"
18
19 /*
20 * 79234640-9e10-4fea-a5c1-b5aa8b19756f
21 * This _DSM GUID returns information about the GPIO lines mapped to a
22 * discrete INT3472 device. Function number 1 returns a count of the GPIO
23 * lines that are mapped. Subsequent functions return 32 bit ints encoding
24 * information about the GPIO line, including its purpose.
25 */
26 static const guid_t int3472_gpio_guid =
27 GUID_INIT(0x79234640, 0x9e10, 0x4fea,
28 0xa5, 0xc1, 0xb5, 0xaa, 0x8b, 0x19, 0x75, 0x6f);
29
30 /*
31 * 822ace8f-2814-4174-a56b-5f029fe079ee
32 * This _DSM GUID returns a string from the sensor device, which acts as a
33 * module identifier.
34 */
35 static const guid_t cio2_sensor_module_guid =
36 GUID_INIT(0x822ace8f, 0x2814, 0x4174,
37 0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee);
38
39 /*
40 * Here follows platform specific mapping information that we can pass to
41 * the functions mapping resources to the sensors. Where the sensors have
42 * a power enable pin defined in DSDT we need to provide a supply name so
43 * the sensor drivers can find the regulator. The device name will be derived
44 * from the sensor's ACPI device within the code. Optionally, we can provide a
45 * NULL terminated array of function name mappings to deal with any platform
46 * specific deviations from the documented behaviour of GPIOs.
47 *
48 * Map a GPIO function name to NULL to prevent the driver from mapping that
49 * GPIO at all.
50 */
51
52 static const struct int3472_gpio_function_remap ov2680_gpio_function_remaps[] = {
53 { "reset", NULL },
54 { "powerdown", "reset" },
55 { }
56 };
57
58 static const struct int3472_sensor_config int3472_sensor_configs[] = {
59 /* Lenovo Miix 510-12ISK - OV2680, Front */
60 { "GNDF140809R", { 0 }, ov2680_gpio_function_remaps },
61 /* Lenovo Miix 510-12ISK - OV5648, Rear */
62 { "GEFF150023R", REGULATOR_SUPPLY("avdd", NULL), NULL },
63 /* Surface Go 1&2 - OV5693, Front */
64 { "YHCU", REGULATOR_SUPPLY("avdd", NULL), NULL },
65 };
66
67 static const struct int3472_sensor_config *
skl_int3472_get_sensor_module_config(struct int3472_discrete_device * int3472)68 skl_int3472_get_sensor_module_config(struct int3472_discrete_device *int3472)
69 {
70 union acpi_object *obj;
71 unsigned int i;
72
73 obj = acpi_evaluate_dsm_typed(int3472->sensor->handle,
74 &cio2_sensor_module_guid, 0x00,
75 0x01, NULL, ACPI_TYPE_STRING);
76
77 if (!obj) {
78 dev_err(int3472->dev,
79 "Failed to get sensor module string from _DSM\n");
80 return ERR_PTR(-ENODEV);
81 }
82
83 if (obj->string.type != ACPI_TYPE_STRING) {
84 dev_err(int3472->dev,
85 "Sensor _DSM returned a non-string value\n");
86
87 ACPI_FREE(obj);
88 return ERR_PTR(-EINVAL);
89 }
90
91 for (i = 0; i < ARRAY_SIZE(int3472_sensor_configs); i++) {
92 if (!strcmp(int3472_sensor_configs[i].sensor_module_name,
93 obj->string.pointer))
94 break;
95 }
96
97 ACPI_FREE(obj);
98
99 if (i >= ARRAY_SIZE(int3472_sensor_configs))
100 return ERR_PTR(-EINVAL);
101
102 return &int3472_sensor_configs[i];
103 }
104
skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio,const char * func,u32 polarity)105 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
106 struct acpi_resource_gpio *agpio,
107 const char *func, u32 polarity)
108 {
109 const struct int3472_sensor_config *sensor_config;
110 char *path = agpio->resource_source.string_ptr;
111 struct gpiod_lookup *table_entry;
112 struct acpi_device *adev;
113 acpi_handle handle;
114 acpi_status status;
115
116 if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) {
117 dev_warn(int3472->dev, "Too many GPIOs mapped\n");
118 return -EINVAL;
119 }
120
121 sensor_config = int3472->sensor_config;
122 if (!IS_ERR(sensor_config) && sensor_config->function_maps) {
123 const struct int3472_gpio_function_remap *remap;
124
125 for (remap = sensor_config->function_maps; remap->documented; remap++) {
126 if (!strcmp(func, remap->documented)) {
127 func = remap->actual;
128 break;
129 }
130 }
131 }
132
133 /* Functions mapped to NULL should not be mapped to the sensor */
134 if (!func)
135 return 0;
136
137 status = acpi_get_handle(NULL, path, &handle);
138 if (ACPI_FAILURE(status))
139 return -EINVAL;
140
141 adev = acpi_fetch_acpi_dev(handle);
142 if (!adev)
143 return -ENODEV;
144
145 table_entry = &int3472->gpios.table[int3472->n_sensor_gpios];
146 table_entry->key = acpi_dev_name(adev);
147 table_entry->chip_hwnum = agpio->pin_table[0];
148 table_entry->con_id = func;
149 table_entry->idx = 0;
150 table_entry->flags = polarity;
151
152 int3472->n_sensor_gpios++;
153
154 return 0;
155 }
156
skl_int3472_map_gpio_to_clk(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio,u8 type)157 static int skl_int3472_map_gpio_to_clk(struct int3472_discrete_device *int3472,
158 struct acpi_resource_gpio *agpio, u8 type)
159 {
160 char *path = agpio->resource_source.string_ptr;
161 u16 pin = agpio->pin_table[0];
162 struct gpio_desc *gpio;
163
164 switch (type) {
165 case INT3472_GPIO_TYPE_CLK_ENABLE:
166 gpio = acpi_get_and_request_gpiod(path, pin, "int3472,clk-enable");
167 if (IS_ERR(gpio))
168 return (PTR_ERR(gpio));
169
170 int3472->clock.ena_gpio = gpio;
171 break;
172 case INT3472_GPIO_TYPE_PRIVACY_LED:
173 gpio = acpi_get_and_request_gpiod(path, pin, "int3472,privacy-led");
174 if (IS_ERR(gpio))
175 return (PTR_ERR(gpio));
176
177 int3472->clock.led_gpio = gpio;
178 break;
179 default:
180 dev_err(int3472->dev, "Invalid GPIO type 0x%02x for clock\n", type);
181 break;
182 }
183
184 return 0;
185 }
186
187 /**
188 * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
189 * @ares: A pointer to a &struct acpi_resource
190 * @data: A pointer to a &struct int3472_discrete_device
191 *
192 * This function handles GPIO resources that are against an INT3472
193 * ACPI device, by checking the value of the corresponding _DSM entry.
194 * This will return a 32bit int, where the lowest byte represents the
195 * function of the GPIO pin:
196 *
197 * 0x00 Reset
198 * 0x01 Power down
199 * 0x0b Power enable
200 * 0x0c Clock enable
201 * 0x0d Privacy LED
202 *
203 * There are some known platform specific quirks where that does not quite
204 * hold up; for example where a pin with type 0x01 (Power down) is mapped to
205 * a sensor pin that performs a reset function or entries in _CRS and _DSM that
206 * do not actually correspond to a physical connection. These will be handled
207 * by the mapping sub-functions.
208 *
209 * GPIOs will either be mapped directly to the sensor device or else used
210 * to create clocks and regulators via the usual frameworks.
211 *
212 * Return:
213 * * 1 - To continue the loop
214 * * 0 - When all resources found are handled properly.
215 * * -EINVAL - If the resource is not a GPIO IO resource
216 * * -ENODEV - If the resource has no corresponding _DSM entry
217 * * -Other - Errors propagated from one of the sub-functions.
218 */
skl_int3472_handle_gpio_resources(struct acpi_resource * ares,void * data)219 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
220 void *data)
221 {
222 struct int3472_discrete_device *int3472 = data;
223 struct acpi_resource_gpio *agpio;
224 union acpi_object *obj;
225 const char *err_msg;
226 int ret;
227 u8 type;
228
229 if (!acpi_gpio_get_io_resource(ares, &agpio))
230 return 1;
231
232 /*
233 * ngpios + 2 because the index of this _DSM function is 1-based and
234 * the first function is just a count.
235 */
236 obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
237 &int3472_gpio_guid, 0x00,
238 int3472->ngpios + 2,
239 NULL, ACPI_TYPE_INTEGER);
240
241 if (!obj) {
242 dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
243 agpio->pin_table[0]);
244 return 1;
245 }
246
247 type = obj->integer.value & 0xff;
248
249 switch (type) {
250 case INT3472_GPIO_TYPE_RESET:
251 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, "reset",
252 GPIO_ACTIVE_LOW);
253 if (ret)
254 err_msg = "Failed to map reset pin to sensor\n";
255
256 break;
257 case INT3472_GPIO_TYPE_POWERDOWN:
258 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, "powerdown",
259 GPIO_ACTIVE_LOW);
260 if (ret)
261 err_msg = "Failed to map powerdown pin to sensor\n";
262
263 break;
264 case INT3472_GPIO_TYPE_CLK_ENABLE:
265 case INT3472_GPIO_TYPE_PRIVACY_LED:
266 ret = skl_int3472_map_gpio_to_clk(int3472, agpio, type);
267 if (ret)
268 err_msg = "Failed to map GPIO to clock\n";
269
270 break;
271 case INT3472_GPIO_TYPE_POWER_ENABLE:
272 ret = skl_int3472_register_regulator(int3472, agpio);
273 if (ret)
274 err_msg = "Failed to map regulator to sensor\n";
275
276 break;
277 default:
278 dev_warn(int3472->dev,
279 "GPIO type 0x%02x unknown; the sensor may not work\n",
280 type);
281 ret = 1;
282 break;
283 }
284
285 int3472->ngpios++;
286 ACPI_FREE(obj);
287
288 if (ret < 0)
289 return dev_err_probe(int3472->dev, ret, err_msg);
290
291 return ret;
292 }
293
skl_int3472_parse_crs(struct int3472_discrete_device * int3472)294 static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
295 {
296 LIST_HEAD(resource_list);
297 int ret;
298
299 /*
300 * No error check, because not having a sensor config is not necessarily
301 * a failure mode.
302 */
303 int3472->sensor_config = skl_int3472_get_sensor_module_config(int3472);
304
305 ret = acpi_dev_get_resources(int3472->adev, &resource_list,
306 skl_int3472_handle_gpio_resources,
307 int3472);
308 if (ret < 0)
309 return ret;
310
311 acpi_dev_free_resource_list(&resource_list);
312
313 /*
314 * If we find no clock enable GPIO pin then the privacy LED won't work.
315 * We've never seen that situation, but it's possible. Warn the user so
316 * it's clear what's happened.
317 */
318 if (int3472->clock.ena_gpio) {
319 ret = skl_int3472_register_clock(int3472);
320 if (ret)
321 return ret;
322 } else {
323 if (int3472->clock.led_gpio)
324 dev_warn(int3472->dev,
325 "No clk GPIO. The privacy LED won't work\n");
326 }
327
328 int3472->gpios.dev_id = int3472->sensor_name;
329 gpiod_add_lookup_table(&int3472->gpios);
330
331 return 0;
332 }
333
skl_int3472_discrete_remove(struct platform_device * pdev)334 static int skl_int3472_discrete_remove(struct platform_device *pdev)
335 {
336 struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev);
337
338 gpiod_remove_lookup_table(&int3472->gpios);
339
340 if (int3472->clock.cl)
341 skl_int3472_unregister_clock(int3472);
342
343 gpiod_put(int3472->clock.ena_gpio);
344 gpiod_put(int3472->clock.led_gpio);
345
346 skl_int3472_unregister_regulator(int3472);
347
348 return 0;
349 }
350
skl_int3472_discrete_probe(struct platform_device * pdev)351 static int skl_int3472_discrete_probe(struct platform_device *pdev)
352 {
353 struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
354 struct int3472_discrete_device *int3472;
355 struct int3472_cldb cldb;
356 int ret;
357
358 ret = skl_int3472_fill_cldb(adev, &cldb);
359 if (ret) {
360 dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
361 return ret;
362 }
363
364 if (cldb.control_logic_type != 1) {
365 dev_err(&pdev->dev, "Unsupported control logic type %u\n",
366 cldb.control_logic_type);
367 return -EINVAL;
368 }
369
370 /* Max num GPIOs we've seen plus a terminator */
371 int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
372 INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
373 if (!int3472)
374 return -ENOMEM;
375
376 int3472->adev = adev;
377 int3472->dev = &pdev->dev;
378 platform_set_drvdata(pdev, int3472);
379
380 ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
381 &int3472->sensor_name);
382 if (ret)
383 return ret;
384
385 /*
386 * Initialising this list means we can call gpiod_remove_lookup_table()
387 * in failure paths without issue.
388 */
389 INIT_LIST_HEAD(&int3472->gpios.list);
390
391 ret = skl_int3472_parse_crs(int3472);
392 if (ret) {
393 skl_int3472_discrete_remove(pdev);
394 return ret;
395 }
396
397 acpi_dev_clear_dependencies(adev);
398 return 0;
399 }
400
401 static const struct acpi_device_id int3472_device_id[] = {
402 { "INT3472", 0 },
403 { }
404 };
405 MODULE_DEVICE_TABLE(acpi, int3472_device_id);
406
407 static struct platform_driver int3472_discrete = {
408 .driver = {
409 .name = "int3472-discrete",
410 .acpi_match_table = int3472_device_id,
411 },
412 .probe = skl_int3472_discrete_probe,
413 .remove = skl_int3472_discrete_remove,
414 };
415 module_platform_driver(int3472_discrete);
416
417 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
418 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
419 MODULE_LICENSE("GPL v2");
420
