1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * DMI based code to deal with broken DSDTs on X86 tablets which ship with
4 * Android as (part of) the factory image. The factory kernels shipped on these
5 * devices typically have a bunch of things hardcoded, rather than specified
6 * in their DSDT.
7 *
8 * Copyright (C) 2021-2023 Hans de Goede <hdegoede@redhat.com>
9 */
10
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13 #include <linux/acpi.h>
14 #include <linux/dmi.h>
15 #include <linux/gpio/driver.h>
16 #include <linux/gpio/machine.h>
17 #include <linux/irq.h>
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
20 #include <linux/serdev.h>
21 #include <linux/string.h>
22
23 #include "x86-android-tablets.h"
24 /* For gpiochip_get_desc() which is EXPORT_SYMBOL_GPL() */
25 #include "../../../gpio/gpiolib.h"
26 #include "../../../gpio/gpiolib-acpi.h"
27
gpiochip_find_match_label(struct gpio_chip * gc,void * data)28 static int gpiochip_find_match_label(struct gpio_chip *gc, void *data)
29 {
30 return gc->label && !strcmp(gc->label, data);
31 }
32
x86_android_tablet_get_gpiod(const char * label,int pin,struct gpio_desc ** desc)33 int x86_android_tablet_get_gpiod(const char *label, int pin, struct gpio_desc **desc)
34 {
35 struct gpio_desc *gpiod;
36 struct gpio_chip *chip;
37
38 chip = gpiochip_find((void *)label, gpiochip_find_match_label);
39 if (!chip) {
40 pr_err("error cannot find GPIO chip %s\n", label);
41 return -ENODEV;
42 }
43
44 gpiod = gpiochip_get_desc(chip, pin);
45 if (IS_ERR(gpiod)) {
46 pr_err("error %ld getting GPIO %s %d\n", PTR_ERR(gpiod), label, pin);
47 return PTR_ERR(gpiod);
48 }
49
50 *desc = gpiod;
51 return 0;
52 }
53
x86_acpi_irq_helper_get(const struct x86_acpi_irq_data * data)54 int x86_acpi_irq_helper_get(const struct x86_acpi_irq_data *data)
55 {
56 struct irq_fwspec fwspec = { };
57 struct irq_domain *domain;
58 struct acpi_device *adev;
59 struct gpio_desc *gpiod;
60 unsigned int irq_type;
61 acpi_handle handle;
62 acpi_status status;
63 int irq, ret;
64
65 switch (data->type) {
66 case X86_ACPI_IRQ_TYPE_APIC:
67 /*
68 * The DSDT may already reference the GSI in a device skipped by
69 * acpi_quirk_skip_i2c_client_enumeration(). Unregister the GSI
70 * to avoid EBUSY errors in this case.
71 */
72 acpi_unregister_gsi(data->index);
73 irq = acpi_register_gsi(NULL, data->index, data->trigger, data->polarity);
74 if (irq < 0)
75 pr_err("error %d getting APIC IRQ %d\n", irq, data->index);
76
77 return irq;
78 case X86_ACPI_IRQ_TYPE_GPIOINT:
79 /* Like acpi_dev_gpio_irq_get(), but without parsing ACPI resources */
80 ret = x86_android_tablet_get_gpiod(data->chip, data->index, &gpiod);
81 if (ret)
82 return ret;
83
84 irq = gpiod_to_irq(gpiod);
85 if (irq < 0) {
86 pr_err("error %d getting IRQ %s %d\n", irq, data->chip, data->index);
87 return irq;
88 }
89
90 irq_type = acpi_dev_get_irq_type(data->trigger, data->polarity);
91 if (irq_type != IRQ_TYPE_NONE && irq_type != irq_get_trigger_type(irq))
92 irq_set_irq_type(irq, irq_type);
93
94 return irq;
95 case X86_ACPI_IRQ_TYPE_PMIC:
96 status = acpi_get_handle(NULL, data->chip, &handle);
97 if (ACPI_FAILURE(status)) {
98 pr_err("error could not get %s handle\n", data->chip);
99 return -ENODEV;
100 }
101
102 adev = acpi_fetch_acpi_dev(handle);
103 if (!adev) {
104 pr_err("error could not get %s adev\n", data->chip);
105 return -ENODEV;
106 }
107
108 fwspec.fwnode = acpi_fwnode_handle(adev);
109 domain = irq_find_matching_fwspec(&fwspec, data->domain);
110 if (!domain) {
111 pr_err("error could not find IRQ domain for %s\n", data->chip);
112 return -ENODEV;
113 }
114
115 return irq_create_mapping(domain, data->index);
116 default:
117 return 0;
118 }
119 }
120
121 static int i2c_client_count;
122 static int pdev_count;
123 static int serdev_count;
124 static struct i2c_client **i2c_clients;
125 static struct platform_device **pdevs;
126 static struct serdev_device **serdevs;
127 static struct gpio_keys_button *buttons;
128 static struct gpiod_lookup_table * const *gpiod_lookup_tables;
129 static const struct software_node *bat_swnode;
130 static void (*exit_handler)(void);
131
x86_instantiate_i2c_client(const struct x86_dev_info * dev_info,int idx)132 static __init int x86_instantiate_i2c_client(const struct x86_dev_info *dev_info,
133 int idx)
134 {
135 const struct x86_i2c_client_info *client_info = &dev_info->i2c_client_info[idx];
136 struct i2c_board_info board_info = client_info->board_info;
137 struct i2c_adapter *adap;
138 acpi_handle handle;
139 acpi_status status;
140
141 board_info.irq = x86_acpi_irq_helper_get(&client_info->irq_data);
142 if (board_info.irq < 0)
143 return board_info.irq;
144
145 status = acpi_get_handle(NULL, client_info->adapter_path, &handle);
146 if (ACPI_FAILURE(status)) {
147 pr_err("Error could not get %s handle\n", client_info->adapter_path);
148 return -ENODEV;
149 }
150
151 adap = i2c_acpi_find_adapter_by_handle(handle);
152 if (!adap) {
153 pr_err("error could not get %s adapter\n", client_info->adapter_path);
154 return -ENODEV;
155 }
156
157 i2c_clients[idx] = i2c_new_client_device(adap, &board_info);
158 put_device(&adap->dev);
159 if (IS_ERR(i2c_clients[idx]))
160 return dev_err_probe(&adap->dev, PTR_ERR(i2c_clients[idx]),
161 "creating I2C-client %d\n", idx);
162
163 return 0;
164 }
165
x86_instantiate_serdev(const struct x86_serdev_info * info,int idx)166 static __init int x86_instantiate_serdev(const struct x86_serdev_info *info, int idx)
167 {
168 struct acpi_device *ctrl_adev, *serdev_adev;
169 struct serdev_device *serdev;
170 struct device *ctrl_dev;
171 int ret = -ENODEV;
172
173 ctrl_adev = acpi_dev_get_first_match_dev(info->ctrl_hid, info->ctrl_uid, -1);
174 if (!ctrl_adev) {
175 pr_err("error could not get %s/%s ctrl adev\n",
176 info->ctrl_hid, info->ctrl_uid);
177 return -ENODEV;
178 }
179
180 serdev_adev = acpi_dev_get_first_match_dev(info->serdev_hid, NULL, -1);
181 if (!serdev_adev) {
182 pr_err("error could not get %s serdev adev\n", info->serdev_hid);
183 goto put_ctrl_adev;
184 }
185
186 /* get_first_physical_node() returns a weak ref, no need to put() it */
187 ctrl_dev = acpi_get_first_physical_node(ctrl_adev);
188 if (!ctrl_dev) {
189 pr_err("error could not get %s/%s ctrl physical dev\n",
190 info->ctrl_hid, info->ctrl_uid);
191 goto put_serdev_adev;
192 }
193
194 /* ctrl_dev now points to the controller's parent, get the controller */
195 ctrl_dev = device_find_child_by_name(ctrl_dev, info->ctrl_devname);
196 if (!ctrl_dev) {
197 pr_err("error could not get %s/%s %s ctrl dev\n",
198 info->ctrl_hid, info->ctrl_uid, info->ctrl_devname);
199 goto put_serdev_adev;
200 }
201
202 serdev = serdev_device_alloc(to_serdev_controller(ctrl_dev));
203 if (!serdev) {
204 ret = -ENOMEM;
205 goto put_serdev_adev;
206 }
207
208 ACPI_COMPANION_SET(&serdev->dev, serdev_adev);
209 acpi_device_set_enumerated(serdev_adev);
210
211 ret = serdev_device_add(serdev);
212 if (ret) {
213 dev_err(&serdev->dev, "error %d adding serdev\n", ret);
214 serdev_device_put(serdev);
215 goto put_serdev_adev;
216 }
217
218 serdevs[idx] = serdev;
219
220 put_serdev_adev:
221 acpi_dev_put(serdev_adev);
222 put_ctrl_adev:
223 acpi_dev_put(ctrl_adev);
224 return ret;
225 }
226
x86_android_tablet_cleanup(void)227 static void x86_android_tablet_cleanup(void)
228 {
229 int i;
230
231 for (i = 0; i < serdev_count; i++) {
232 if (serdevs[i])
233 serdev_device_remove(serdevs[i]);
234 }
235
236 kfree(serdevs);
237
238 for (i = 0; i < pdev_count; i++)
239 platform_device_unregister(pdevs[i]);
240
241 kfree(pdevs);
242 kfree(buttons);
243
244 for (i = 0; i < i2c_client_count; i++)
245 i2c_unregister_device(i2c_clients[i]);
246
247 kfree(i2c_clients);
248
249 if (exit_handler)
250 exit_handler();
251
252 for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++)
253 gpiod_remove_lookup_table(gpiod_lookup_tables[i]);
254
255 software_node_unregister(bat_swnode);
256 }
257
x86_android_tablet_init(void)258 static __init int x86_android_tablet_init(void)
259 {
260 const struct x86_dev_info *dev_info;
261 const struct dmi_system_id *id;
262 struct gpio_chip *chip;
263 int i, ret = 0;
264
265 id = dmi_first_match(x86_android_tablet_ids);
266 if (!id)
267 return -ENODEV;
268
269 dev_info = id->driver_data;
270
271 /*
272 * The broken DSDTs on these devices often also include broken
273 * _AEI (ACPI Event Interrupt) handlers, disable these.
274 */
275 if (dev_info->invalid_aei_gpiochip) {
276 chip = gpiochip_find(dev_info->invalid_aei_gpiochip,
277 gpiochip_find_match_label);
278 if (!chip) {
279 pr_err("error cannot find GPIO chip %s\n", dev_info->invalid_aei_gpiochip);
280 return -ENODEV;
281 }
282 acpi_gpiochip_free_interrupts(chip);
283 }
284
285 /*
286 * Since this runs from module_init() it cannot use -EPROBE_DEFER,
287 * instead pre-load any modules which are listed as requirements.
288 */
289 for (i = 0; dev_info->modules && dev_info->modules[i]; i++)
290 request_module(dev_info->modules[i]);
291
292 bat_swnode = dev_info->bat_swnode;
293 if (bat_swnode) {
294 ret = software_node_register(bat_swnode);
295 if (ret)
296 return ret;
297 }
298
299 gpiod_lookup_tables = dev_info->gpiod_lookup_tables;
300 for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++)
301 gpiod_add_lookup_table(gpiod_lookup_tables[i]);
302
303 if (dev_info->init) {
304 ret = dev_info->init();
305 if (ret < 0) {
306 x86_android_tablet_cleanup();
307 return ret;
308 }
309 exit_handler = dev_info->exit;
310 }
311
312 i2c_clients = kcalloc(dev_info->i2c_client_count, sizeof(*i2c_clients), GFP_KERNEL);
313 if (!i2c_clients) {
314 x86_android_tablet_cleanup();
315 return -ENOMEM;
316 }
317
318 i2c_client_count = dev_info->i2c_client_count;
319 for (i = 0; i < i2c_client_count; i++) {
320 ret = x86_instantiate_i2c_client(dev_info, i);
321 if (ret < 0) {
322 x86_android_tablet_cleanup();
323 return ret;
324 }
325 }
326
327 /* + 1 to make space for (optional) gpio_keys_button pdev */
328 pdevs = kcalloc(dev_info->pdev_count + 1, sizeof(*pdevs), GFP_KERNEL);
329 if (!pdevs) {
330 x86_android_tablet_cleanup();
331 return -ENOMEM;
332 }
333
334 pdev_count = dev_info->pdev_count;
335 for (i = 0; i < pdev_count; i++) {
336 pdevs[i] = platform_device_register_full(&dev_info->pdev_info[i]);
337 if (IS_ERR(pdevs[i])) {
338 x86_android_tablet_cleanup();
339 return PTR_ERR(pdevs[i]);
340 }
341 }
342
343 serdevs = kcalloc(dev_info->serdev_count, sizeof(*serdevs), GFP_KERNEL);
344 if (!serdevs) {
345 x86_android_tablet_cleanup();
346 return -ENOMEM;
347 }
348
349 serdev_count = dev_info->serdev_count;
350 for (i = 0; i < serdev_count; i++) {
351 ret = x86_instantiate_serdev(&dev_info->serdev_info[i], i);
352 if (ret < 0) {
353 x86_android_tablet_cleanup();
354 return ret;
355 }
356 }
357
358 if (dev_info->gpio_button_count) {
359 struct gpio_keys_platform_data pdata = { };
360 struct gpio_desc *gpiod;
361
362 buttons = kcalloc(dev_info->gpio_button_count, sizeof(*buttons), GFP_KERNEL);
363 if (!buttons) {
364 x86_android_tablet_cleanup();
365 return -ENOMEM;
366 }
367
368 for (i = 0; i < dev_info->gpio_button_count; i++) {
369 ret = x86_android_tablet_get_gpiod(dev_info->gpio_button[i].chip,
370 dev_info->gpio_button[i].pin, &gpiod);
371 if (ret < 0) {
372 x86_android_tablet_cleanup();
373 return ret;
374 }
375
376 buttons[i] = dev_info->gpio_button[i].button;
377 buttons[i].gpio = desc_to_gpio(gpiod);
378 }
379
380 pdata.buttons = buttons;
381 pdata.nbuttons = dev_info->gpio_button_count;
382
383 pdevs[pdev_count] = platform_device_register_data(NULL, "gpio-keys",
384 PLATFORM_DEVID_AUTO,
385 &pdata, sizeof(pdata));
386 if (IS_ERR(pdevs[pdev_count])) {
387 x86_android_tablet_cleanup();
388 return PTR_ERR(pdevs[pdev_count]);
389 }
390 pdev_count++;
391 }
392
393 return 0;
394 }
395
396 module_init(x86_android_tablet_init);
397 module_exit(x86_android_tablet_cleanup);
398
399 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
400 MODULE_DESCRIPTION("X86 Android tablets DSDT fixups driver");
401 MODULE_LICENSE("GPL");
402