1 // SPDX-License-Identifier: GPL-2.0
2 /* Author: Dan Scally <djrscally@gmail.com> */
3
4 #include <linux/acpi.h>
5 #include <linux/bitfield.h>
6 #include <linux/device.h>
7 #include <linux/gpio/consumer.h>
8 #include <linux/gpio/machine.h>
9 #include <linux/i2c.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/overflow.h>
13 #include <linux/platform_device.h>
14 #include <linux/string_choices.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 #define INT3472_GPIO_DSM_TYPE GENMASK(7, 0)
31 #define INT3472_GPIO_DSM_PIN GENMASK(15, 8)
32 #define INT3472_GPIO_DSM_SENSOR_ON_VAL GENMASK(31, 24)
33
34 /*
35 * 822ace8f-2814-4174-a56b-5f029fe079ee
36 * This _DSM GUID returns a string from the sensor device, which acts as a
37 * module identifier.
38 */
39 static const guid_t cio2_sensor_module_guid =
40 GUID_INIT(0x822ace8f, 0x2814, 0x4174,
41 0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee);
42
skl_int3472_log_sensor_module_name(struct int3472_discrete_device * int3472)43 static void skl_int3472_log_sensor_module_name(struct int3472_discrete_device *int3472)
44 {
45 union acpi_object *obj;
46
47 obj = acpi_evaluate_dsm_typed(int3472->sensor->handle,
48 &cio2_sensor_module_guid, 0x00,
49 0x01, NULL, ACPI_TYPE_STRING);
50 if (obj) {
51 dev_dbg(int3472->dev, "Sensor module id: '%s'\n", obj->string.pointer);
52 ACPI_FREE(obj);
53 }
54 }
55
skl_int3472_fill_gpiod_lookup(struct gpiod_lookup * table_entry,struct acpi_resource_gpio * agpio,const char * func,u32 polarity)56 static int skl_int3472_fill_gpiod_lookup(struct gpiod_lookup *table_entry,
57 struct acpi_resource_gpio *agpio,
58 const char *func, u32 polarity)
59 {
60 char *path = agpio->resource_source.string_ptr;
61 struct acpi_device *adev;
62 acpi_handle handle;
63 acpi_status status;
64
65 status = acpi_get_handle(NULL, path, &handle);
66 if (ACPI_FAILURE(status))
67 return -EINVAL;
68
69 adev = acpi_fetch_acpi_dev(handle);
70 if (!adev)
71 return -ENODEV;
72
73 *table_entry = GPIO_LOOKUP(acpi_dev_name(adev), agpio->pin_table[0], func, polarity);
74
75 return 0;
76 }
77
skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio,const char * func,u32 polarity)78 static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
79 struct acpi_resource_gpio *agpio,
80 const char *func, u32 polarity)
81 {
82 int ret;
83
84 if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) {
85 dev_warn(int3472->dev, "Too many GPIOs mapped\n");
86 return -EINVAL;
87 }
88
89 ret = skl_int3472_fill_gpiod_lookup(&int3472->gpios.table[int3472->n_sensor_gpios],
90 agpio, func, polarity);
91 if (ret)
92 return ret;
93
94 int3472->n_sensor_gpios++;
95
96 return 0;
97 }
98
99 /* This should *really* only be used when there's no other way... */
100 static struct gpio_desc *
skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device * int3472,struct acpi_resource_gpio * agpio,const char * func,u32 polarity)101 skl_int3472_gpiod_get_from_temp_lookup(struct int3472_discrete_device *int3472,
102 struct acpi_resource_gpio *agpio,
103 const char *func, u32 polarity)
104 {
105 struct gpio_desc *desc;
106 int ret;
107
108 struct gpiod_lookup_table *lookup __free(kfree) =
109 kzalloc(struct_size(lookup, table, 2), GFP_KERNEL);
110 if (!lookup)
111 return ERR_PTR(-ENOMEM);
112
113 lookup->dev_id = dev_name(int3472->dev);
114 ret = skl_int3472_fill_gpiod_lookup(&lookup->table[0], agpio, func, polarity);
115 if (ret)
116 return ERR_PTR(ret);
117
118 gpiod_add_lookup_table(lookup);
119 desc = devm_gpiod_get(int3472->dev, func, GPIOD_OUT_LOW);
120 gpiod_remove_lookup_table(lookup);
121
122 return desc;
123 }
124
int3472_get_func_and_polarity(u8 type,const char ** func,u32 * polarity)125 static void int3472_get_func_and_polarity(u8 type, const char **func, u32 *polarity)
126 {
127 switch (type) {
128 case INT3472_GPIO_TYPE_RESET:
129 *func = "reset";
130 *polarity = GPIO_ACTIVE_LOW;
131 break;
132 case INT3472_GPIO_TYPE_POWERDOWN:
133 *func = "powerdown";
134 *polarity = GPIO_ACTIVE_LOW;
135 break;
136 case INT3472_GPIO_TYPE_CLK_ENABLE:
137 *func = "clk-enable";
138 *polarity = GPIO_ACTIVE_HIGH;
139 break;
140 case INT3472_GPIO_TYPE_PRIVACY_LED:
141 *func = "privacy-led";
142 *polarity = GPIO_ACTIVE_HIGH;
143 break;
144 case INT3472_GPIO_TYPE_POWER_ENABLE:
145 *func = "power-enable";
146 *polarity = GPIO_ACTIVE_HIGH;
147 break;
148 default:
149 *func = "unknown";
150 *polarity = GPIO_ACTIVE_HIGH;
151 break;
152 }
153 }
154
155 /**
156 * skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
157 * @ares: A pointer to a &struct acpi_resource
158 * @data: A pointer to a &struct int3472_discrete_device
159 *
160 * This function handles GPIO resources that are against an INT3472
161 * ACPI device, by checking the value of the corresponding _DSM entry.
162 * This will return a 32bit int, where the lowest byte represents the
163 * function of the GPIO pin:
164 *
165 * 0x00 Reset
166 * 0x01 Power down
167 * 0x0b Power enable
168 * 0x0c Clock enable
169 * 0x0d Privacy LED
170 *
171 * There are some known platform specific quirks where that does not quite
172 * hold up; for example where a pin with type 0x01 (Power down) is mapped to
173 * a sensor pin that performs a reset function or entries in _CRS and _DSM that
174 * do not actually correspond to a physical connection. These will be handled
175 * by the mapping sub-functions.
176 *
177 * GPIOs will either be mapped directly to the sensor device or else used
178 * to create clocks and regulators via the usual frameworks.
179 *
180 * Return:
181 * * 1 - To continue the loop
182 * * 0 - When all resources found are handled properly.
183 * * -EINVAL - If the resource is not a GPIO IO resource
184 * * -ENODEV - If the resource has no corresponding _DSM entry
185 * * -Other - Errors propagated from one of the sub-functions.
186 */
skl_int3472_handle_gpio_resources(struct acpi_resource * ares,void * data)187 static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
188 void *data)
189 {
190 struct int3472_discrete_device *int3472 = data;
191 struct acpi_resource_gpio *agpio;
192 u8 active_value, pin, type;
193 union acpi_object *obj;
194 struct gpio_desc *gpio;
195 const char *err_msg;
196 const char *func;
197 u32 polarity;
198 int ret;
199
200 if (!acpi_gpio_get_io_resource(ares, &agpio))
201 return 1;
202
203 /*
204 * ngpios + 2 because the index of this _DSM function is 1-based and
205 * the first function is just a count.
206 */
207 obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
208 &int3472_gpio_guid, 0x00,
209 int3472->ngpios + 2,
210 NULL, ACPI_TYPE_INTEGER);
211
212 if (!obj) {
213 dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
214 agpio->pin_table[0]);
215 return 1;
216 }
217
218 type = FIELD_GET(INT3472_GPIO_DSM_TYPE, obj->integer.value);
219
220 int3472_get_func_and_polarity(type, &func, &polarity);
221
222 pin = FIELD_GET(INT3472_GPIO_DSM_PIN, obj->integer.value);
223 if (pin != agpio->pin_table[0])
224 dev_warn(int3472->dev, "%s %s pin number mismatch _DSM %d resource %d\n",
225 func, agpio->resource_source.string_ptr, pin,
226 agpio->pin_table[0]);
227
228 active_value = FIELD_GET(INT3472_GPIO_DSM_SENSOR_ON_VAL, obj->integer.value);
229 if (!active_value)
230 polarity ^= GPIO_ACTIVE_LOW;
231
232 dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", func,
233 agpio->resource_source.string_ptr, agpio->pin_table[0],
234 str_high_low(polarity == GPIO_ACTIVE_HIGH));
235
236 switch (type) {
237 case INT3472_GPIO_TYPE_RESET:
238 case INT3472_GPIO_TYPE_POWERDOWN:
239 ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, polarity);
240 if (ret)
241 err_msg = "Failed to map GPIO pin to sensor\n";
242
243 break;
244 case INT3472_GPIO_TYPE_CLK_ENABLE:
245 case INT3472_GPIO_TYPE_PRIVACY_LED:
246 case INT3472_GPIO_TYPE_POWER_ENABLE:
247 gpio = skl_int3472_gpiod_get_from_temp_lookup(int3472, agpio, func, polarity);
248 if (IS_ERR(gpio)) {
249 ret = PTR_ERR(gpio);
250 err_msg = "Failed to get GPIO\n";
251 break;
252 }
253
254 switch (type) {
255 case INT3472_GPIO_TYPE_CLK_ENABLE:
256 ret = skl_int3472_register_gpio_clock(int3472, gpio);
257 if (ret)
258 err_msg = "Failed to register clock\n";
259
260 break;
261 case INT3472_GPIO_TYPE_PRIVACY_LED:
262 ret = skl_int3472_register_pled(int3472, gpio);
263 if (ret)
264 err_msg = "Failed to register LED\n";
265
266 break;
267 case INT3472_GPIO_TYPE_POWER_ENABLE:
268 ret = skl_int3472_register_regulator(int3472, gpio);
269 if (ret)
270 err_msg = "Failed to map regulator to sensor\n";
271
272 break;
273 default: /* Never reached */
274 ret = -EINVAL;
275 break;
276 }
277 break;
278 default:
279 dev_warn(int3472->dev,
280 "GPIO type 0x%02x unknown; the sensor may not work\n",
281 type);
282 ret = 1;
283 break;
284 }
285
286 int3472->ngpios++;
287 ACPI_FREE(obj);
288
289 if (ret < 0)
290 return dev_err_probe(int3472->dev, ret, err_msg);
291
292 return ret;
293 }
294
skl_int3472_parse_crs(struct int3472_discrete_device * int3472)295 static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
296 {
297 LIST_HEAD(resource_list);
298 int ret;
299
300 skl_int3472_log_sensor_module_name(int3472);
301
302 ret = acpi_dev_get_resources(int3472->adev, &resource_list,
303 skl_int3472_handle_gpio_resources,
304 int3472);
305 if (ret < 0)
306 return ret;
307
308 acpi_dev_free_resource_list(&resource_list);
309
310 /* Register _DSM based clock (no-op if a GPIO clock was already registered) */
311 ret = skl_int3472_register_dsm_clock(int3472);
312 if (ret < 0)
313 return ret;
314
315 int3472->gpios.dev_id = int3472->sensor_name;
316 gpiod_add_lookup_table(&int3472->gpios);
317
318 return 0;
319 }
320
skl_int3472_discrete_remove(struct platform_device * pdev)321 static void skl_int3472_discrete_remove(struct platform_device *pdev)
322 {
323 struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev);
324
325 gpiod_remove_lookup_table(&int3472->gpios);
326
327 skl_int3472_unregister_clock(int3472);
328 skl_int3472_unregister_pled(int3472);
329 skl_int3472_unregister_regulator(int3472);
330 }
331
skl_int3472_discrete_probe(struct platform_device * pdev)332 static int skl_int3472_discrete_probe(struct platform_device *pdev)
333 {
334 struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
335 struct int3472_discrete_device *int3472;
336 struct int3472_cldb cldb;
337 int ret;
338
339 ret = skl_int3472_fill_cldb(adev, &cldb);
340 if (ret) {
341 dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
342 return ret;
343 }
344
345 if (cldb.control_logic_type != 1) {
346 dev_err(&pdev->dev, "Unsupported control logic type %u\n",
347 cldb.control_logic_type);
348 return -EINVAL;
349 }
350
351 /* Max num GPIOs we've seen plus a terminator */
352 int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
353 INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
354 if (!int3472)
355 return -ENOMEM;
356
357 int3472->adev = adev;
358 int3472->dev = &pdev->dev;
359 platform_set_drvdata(pdev, int3472);
360 int3472->clock.imgclk_index = cldb.clock_source;
361
362 ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
363 &int3472->sensor_name);
364 if (ret)
365 return ret;
366
367 /*
368 * Initialising this list means we can call gpiod_remove_lookup_table()
369 * in failure paths without issue.
370 */
371 INIT_LIST_HEAD(&int3472->gpios.list);
372
373 ret = skl_int3472_parse_crs(int3472);
374 if (ret) {
375 skl_int3472_discrete_remove(pdev);
376 return ret;
377 }
378
379 acpi_dev_clear_dependencies(adev);
380 return 0;
381 }
382
383 static const struct acpi_device_id int3472_device_id[] = {
384 { "INT3472", 0 },
385 { }
386 };
387 MODULE_DEVICE_TABLE(acpi, int3472_device_id);
388
389 static struct platform_driver int3472_discrete = {
390 .driver = {
391 .name = "int3472-discrete",
392 .acpi_match_table = int3472_device_id,
393 },
394 .probe = skl_int3472_discrete_probe,
395 .remove = skl_int3472_discrete_remove,
396 };
397 module_platform_driver(int3472_discrete);
398
399 MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
400 MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
401 MODULE_LICENSE("GPL v2");
402