1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux I2C core ACPI support code
4 *
5 * Copyright (C) 2014 Intel Corp, Author: Lan Tianyu <tianyu.lan@intel.com>
6 */
7
8 #include <linux/acpi.h>
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/i2c.h>
12 #include <linux/list.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15
16 #include "i2c-core.h"
17
18 struct i2c_acpi_handler_data {
19 struct acpi_connection_info info;
20 struct i2c_adapter *adapter;
21 };
22
23 struct gsb_buffer {
24 u8 status;
25 u8 len;
26 union {
27 u16 wdata;
28 u8 bdata;
29 DECLARE_FLEX_ARRAY(u8, data);
30 };
31 } __packed;
32
33 struct i2c_acpi_lookup {
34 struct i2c_board_info *info;
35 acpi_handle adapter_handle;
36 acpi_handle device_handle;
37 acpi_handle search_handle;
38 int n;
39 int index;
40 u32 speed;
41 u32 min_speed;
42 u32 force_speed;
43 };
44
45 /**
46 * i2c_acpi_get_i2c_resource - Gets I2cSerialBus resource if type matches
47 * @ares: ACPI resource
48 * @i2c: Pointer to I2cSerialBus resource will be returned here
49 *
50 * Checks if the given ACPI resource is of type I2cSerialBus.
51 * In this case, returns a pointer to it to the caller.
52 *
53 * Returns true if resource type is of I2cSerialBus, otherwise false.
54 */
i2c_acpi_get_i2c_resource(struct acpi_resource * ares,struct acpi_resource_i2c_serialbus ** i2c)55 bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares,
56 struct acpi_resource_i2c_serialbus **i2c)
57 {
58 struct acpi_resource_i2c_serialbus *sb;
59
60 if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
61 return false;
62
63 sb = &ares->data.i2c_serial_bus;
64 if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C)
65 return false;
66
67 *i2c = sb;
68 return true;
69 }
70 EXPORT_SYMBOL_GPL(i2c_acpi_get_i2c_resource);
71
i2c_acpi_resource_count(struct acpi_resource * ares,void * data)72 static int i2c_acpi_resource_count(struct acpi_resource *ares, void *data)
73 {
74 struct acpi_resource_i2c_serialbus *sb;
75 int *count = data;
76
77 if (i2c_acpi_get_i2c_resource(ares, &sb))
78 *count = *count + 1;
79
80 return 1;
81 }
82
83 /**
84 * i2c_acpi_client_count - Count the number of I2cSerialBus resources
85 * @adev: ACPI device
86 *
87 * Returns the number of I2cSerialBus resources in the ACPI-device's
88 * resource-list; or a negative error code.
89 */
i2c_acpi_client_count(struct acpi_device * adev)90 int i2c_acpi_client_count(struct acpi_device *adev)
91 {
92 int ret, count = 0;
93 LIST_HEAD(r);
94
95 ret = acpi_dev_get_resources(adev, &r, i2c_acpi_resource_count, &count);
96 if (ret < 0)
97 return ret;
98
99 acpi_dev_free_resource_list(&r);
100 return count;
101 }
102 EXPORT_SYMBOL_GPL(i2c_acpi_client_count);
103
i2c_acpi_fill_info(struct acpi_resource * ares,void * data)104 static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data)
105 {
106 struct i2c_acpi_lookup *lookup = data;
107 struct i2c_board_info *info = lookup->info;
108 struct acpi_resource_i2c_serialbus *sb;
109 acpi_status status;
110
111 if (info->addr || !i2c_acpi_get_i2c_resource(ares, &sb))
112 return 1;
113
114 if (lookup->index != -1 && lookup->n++ != lookup->index)
115 return 1;
116
117 status = acpi_get_handle(lookup->device_handle,
118 sb->resource_source.string_ptr,
119 &lookup->adapter_handle);
120 if (ACPI_FAILURE(status))
121 return 1;
122
123 info->addr = sb->slave_address;
124 lookup->speed = sb->connection_speed;
125 if (sb->access_mode == ACPI_I2C_10BIT_MODE)
126 info->flags |= I2C_CLIENT_TEN;
127
128 return 1;
129 }
130
131 static const struct acpi_device_id i2c_acpi_ignored_device_ids[] = {
132 /*
133 * ACPI video acpi_devices, which are handled by the acpi-video driver
134 * sometimes contain a SERIAL_TYPE_I2C ACPI resource, ignore these.
135 */
136 { ACPI_VIDEO_HID, 0 },
137 {}
138 };
139
140 struct i2c_acpi_irq_context {
141 int irq;
142 bool wake_capable;
143 };
144
i2c_acpi_do_lookup(struct acpi_device * adev,struct i2c_acpi_lookup * lookup)145 static int i2c_acpi_do_lookup(struct acpi_device *adev,
146 struct i2c_acpi_lookup *lookup)
147 {
148 struct i2c_board_info *info = lookup->info;
149 struct list_head resource_list;
150 int ret;
151
152 if (acpi_bus_get_status(adev))
153 return -EINVAL;
154
155 if (!acpi_dev_ready_for_enumeration(adev))
156 return -ENODEV;
157
158 if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0)
159 return -ENODEV;
160
161 memset(info, 0, sizeof(*info));
162 lookup->device_handle = acpi_device_handle(adev);
163
164 /* Look up for I2cSerialBus resource */
165 INIT_LIST_HEAD(&resource_list);
166 ret = acpi_dev_get_resources(adev, &resource_list,
167 i2c_acpi_fill_info, lookup);
168 acpi_dev_free_resource_list(&resource_list);
169
170 if (ret < 0 || !info->addr)
171 return -EINVAL;
172
173 return 0;
174 }
175
i2c_acpi_add_irq_resource(struct acpi_resource * ares,void * data)176 static int i2c_acpi_add_irq_resource(struct acpi_resource *ares, void *data)
177 {
178 struct i2c_acpi_irq_context *irq_ctx = data;
179 struct resource r;
180
181 if (irq_ctx->irq > 0)
182 return 1;
183
184 if (!acpi_dev_resource_interrupt(ares, 0, &r))
185 return 1;
186
187 irq_ctx->irq = i2c_dev_irq_from_resources(&r, 1);
188 irq_ctx->wake_capable = r.flags & IORESOURCE_IRQ_WAKECAPABLE;
189
190 return 1; /* No need to add resource to the list */
191 }
192
193 /**
194 * i2c_acpi_get_irq - get device IRQ number from ACPI
195 * @client: Pointer to the I2C client device
196 * @wake_capable: Set to true if the IRQ is wake capable
197 *
198 * Find the IRQ number used by a specific client device.
199 *
200 * Return: The IRQ number or an error code.
201 */
i2c_acpi_get_irq(struct i2c_client * client,bool * wake_capable)202 int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
203 {
204 struct acpi_device *adev = ACPI_COMPANION(&client->dev);
205 struct list_head resource_list;
206 struct i2c_acpi_irq_context irq_ctx = {
207 .irq = -ENOENT,
208 };
209 int ret;
210
211 INIT_LIST_HEAD(&resource_list);
212
213 ret = acpi_dev_get_resources(adev, &resource_list,
214 i2c_acpi_add_irq_resource, &irq_ctx);
215 if (ret < 0)
216 return ret;
217
218 acpi_dev_free_resource_list(&resource_list);
219
220 if (irq_ctx.irq == -ENOENT)
221 irq_ctx.irq = acpi_dev_gpio_irq_wake_get(adev, 0, &irq_ctx.wake_capable);
222
223 if (irq_ctx.irq < 0)
224 return irq_ctx.irq;
225
226 if (wake_capable)
227 *wake_capable = irq_ctx.wake_capable;
228
229 return irq_ctx.irq;
230 }
231
i2c_acpi_get_info(struct acpi_device * adev,struct i2c_board_info * info,struct i2c_adapter * adapter,acpi_handle * adapter_handle)232 static int i2c_acpi_get_info(struct acpi_device *adev,
233 struct i2c_board_info *info,
234 struct i2c_adapter *adapter,
235 acpi_handle *adapter_handle)
236 {
237 struct i2c_acpi_lookup lookup;
238 int ret;
239
240 memset(&lookup, 0, sizeof(lookup));
241 lookup.info = info;
242 lookup.index = -1;
243
244 if (acpi_device_enumerated(adev))
245 return -EINVAL;
246
247 ret = i2c_acpi_do_lookup(adev, &lookup);
248 if (ret)
249 return ret;
250
251 if (adapter) {
252 /* The adapter must match the one in I2cSerialBus() connector */
253 if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle)
254 return -ENODEV;
255 } else {
256 struct acpi_device *adapter_adev;
257
258 /* The adapter must be present */
259 adapter_adev = acpi_fetch_acpi_dev(lookup.adapter_handle);
260 if (!adapter_adev)
261 return -ENODEV;
262 if (acpi_bus_get_status(adapter_adev) ||
263 !adapter_adev->status.present)
264 return -ENODEV;
265 }
266
267 info->fwnode = acpi_fwnode_handle(adev);
268 if (adapter_handle)
269 *adapter_handle = lookup.adapter_handle;
270
271 acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
272 sizeof(info->type));
273
274 return 0;
275 }
276
i2c_acpi_register_device(struct i2c_adapter * adapter,struct acpi_device * adev,struct i2c_board_info * info)277 static void i2c_acpi_register_device(struct i2c_adapter *adapter,
278 struct acpi_device *adev,
279 struct i2c_board_info *info)
280 {
281 /*
282 * Skip registration on boards where the ACPI tables are
283 * known to contain bogus I2C devices.
284 */
285 if (acpi_quirk_skip_i2c_client_enumeration(adev))
286 return;
287
288 adev->power.flags.ignore_parent = true;
289 acpi_device_set_enumerated(adev);
290
291 if (IS_ERR(i2c_new_client_device(adapter, info)))
292 adev->power.flags.ignore_parent = false;
293 }
294
i2c_acpi_add_device(acpi_handle handle,u32 level,void * data,void ** return_value)295 static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
296 void *data, void **return_value)
297 {
298 struct i2c_adapter *adapter = data;
299 struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
300 struct i2c_board_info info;
301
302 if (!adev || i2c_acpi_get_info(adev, &info, adapter, NULL))
303 return AE_OK;
304
305 i2c_acpi_register_device(adapter, adev, &info);
306
307 return AE_OK;
308 }
309
310 #define I2C_ACPI_MAX_SCAN_DEPTH 32
311
312 /**
313 * i2c_acpi_register_devices - enumerate I2C slave devices behind adapter
314 * @adap: pointer to adapter
315 *
316 * Enumerate all I2C slave devices behind this adapter by walking the ACPI
317 * namespace. When a device is found it will be added to the Linux device
318 * model and bound to the corresponding ACPI handle.
319 */
i2c_acpi_register_devices(struct i2c_adapter * adap)320 void i2c_acpi_register_devices(struct i2c_adapter *adap)
321 {
322 struct acpi_device *adev;
323 acpi_status status;
324
325 if (!has_acpi_companion(&adap->dev))
326 return;
327
328 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
329 I2C_ACPI_MAX_SCAN_DEPTH,
330 i2c_acpi_add_device, NULL,
331 adap, NULL);
332 if (ACPI_FAILURE(status))
333 dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
334
335 if (!adap->dev.parent)
336 return;
337
338 adev = ACPI_COMPANION(adap->dev.parent);
339 if (!adev)
340 return;
341
342 acpi_dev_clear_dependencies(adev);
343 }
344
345 static const struct acpi_device_id i2c_acpi_force_400khz_device_ids[] = {
346 /*
347 * These Silead touchscreen controllers only work at 400KHz, for
348 * some reason they do not work at 100KHz. On some devices the ACPI
349 * tables list another device at their bus as only being capable
350 * of 100KHz, testing has shown that these other devices work fine
351 * at 400KHz (as can be expected of any recent i2c hw) so we force
352 * the speed of the bus to 400 KHz if a Silead device is present.
353 */
354 { "MSSL1680", 0 },
355 {}
356 };
357
i2c_acpi_lookup_speed(acpi_handle handle,u32 level,void * data,void ** return_value)358 static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level,
359 void *data, void **return_value)
360 {
361 struct i2c_acpi_lookup *lookup = data;
362 struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
363
364 if (!adev || i2c_acpi_do_lookup(adev, lookup))
365 return AE_OK;
366
367 if (lookup->search_handle != lookup->adapter_handle)
368 return AE_OK;
369
370 if (lookup->speed <= lookup->min_speed)
371 lookup->min_speed = lookup->speed;
372
373 if (acpi_match_device_ids(adev, i2c_acpi_force_400khz_device_ids) == 0)
374 lookup->force_speed = I2C_MAX_FAST_MODE_FREQ;
375
376 return AE_OK;
377 }
378
379 /**
380 * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI
381 * @dev: The device owning the bus
382 *
383 * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves
384 * devices connected to this bus and use the speed of slowest device.
385 *
386 * Returns the speed in Hz or zero
387 */
i2c_acpi_find_bus_speed(struct device * dev)388 u32 i2c_acpi_find_bus_speed(struct device *dev)
389 {
390 struct i2c_acpi_lookup lookup;
391 struct i2c_board_info dummy;
392 acpi_status status;
393
394 if (!has_acpi_companion(dev))
395 return 0;
396
397 memset(&lookup, 0, sizeof(lookup));
398 lookup.search_handle = ACPI_HANDLE(dev);
399 lookup.min_speed = UINT_MAX;
400 lookup.info = &dummy;
401 lookup.index = -1;
402
403 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
404 I2C_ACPI_MAX_SCAN_DEPTH,
405 i2c_acpi_lookup_speed, NULL,
406 &lookup, NULL);
407
408 if (ACPI_FAILURE(status)) {
409 dev_warn(dev, "unable to find I2C bus speed from ACPI\n");
410 return 0;
411 }
412
413 if (lookup.force_speed) {
414 if (lookup.force_speed != lookup.min_speed)
415 dev_warn(dev, FW_BUG "DSDT uses known not-working I2C bus speed %d, forcing it to %d\n",
416 lookup.min_speed, lookup.force_speed);
417 return lookup.force_speed;
418 } else if (lookup.min_speed != UINT_MAX) {
419 return lookup.min_speed;
420 } else {
421 return 0;
422 }
423 }
424 EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed);
425
i2c_acpi_find_adapter_by_handle(acpi_handle handle)426 struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle)
427 {
428 struct i2c_adapter *adapter;
429 struct device *dev;
430
431 dev = bus_find_device(&i2c_bus_type, NULL, handle, device_match_acpi_handle);
432 if (!dev)
433 return NULL;
434
435 adapter = i2c_verify_adapter(dev);
436 if (!adapter)
437 put_device(dev);
438
439 return adapter;
440 }
441 EXPORT_SYMBOL_GPL(i2c_acpi_find_adapter_by_handle);
442
i2c_acpi_find_client_by_adev(struct acpi_device * adev)443 static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
444 {
445 return i2c_find_device_by_fwnode(acpi_fwnode_handle(adev));
446 }
447
i2c_acpi_find_adapter_by_adev(struct acpi_device * adev)448 static struct i2c_adapter *i2c_acpi_find_adapter_by_adev(struct acpi_device *adev)
449 {
450 return i2c_find_adapter_by_fwnode(acpi_fwnode_handle(adev));
451 }
452
i2c_acpi_notify(struct notifier_block * nb,unsigned long value,void * arg)453 static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
454 void *arg)
455 {
456 struct acpi_device *adev = arg;
457 struct i2c_board_info info;
458 acpi_handle adapter_handle;
459 struct i2c_adapter *adapter;
460 struct i2c_client *client;
461
462 switch (value) {
463 case ACPI_RECONFIG_DEVICE_ADD:
464 if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle))
465 break;
466
467 adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
468 if (!adapter)
469 break;
470
471 i2c_acpi_register_device(adapter, adev, &info);
472 put_device(&adapter->dev);
473 break;
474 case ACPI_RECONFIG_DEVICE_REMOVE:
475 if (!acpi_device_enumerated(adev))
476 break;
477
478 client = i2c_acpi_find_client_by_adev(adev);
479 if (client) {
480 i2c_unregister_device(client);
481 put_device(&client->dev);
482 }
483
484 adapter = i2c_acpi_find_adapter_by_adev(adev);
485 if (adapter) {
486 acpi_unbind_one(&adapter->dev);
487 put_device(&adapter->dev);
488 }
489
490 break;
491 }
492
493 return NOTIFY_OK;
494 }
495
496 struct notifier_block i2c_acpi_notifier = {
497 .notifier_call = i2c_acpi_notify,
498 };
499
500 /**
501 * i2c_acpi_new_device_by_fwnode - Create i2c-client for the Nth I2cSerialBus resource
502 * @fwnode: fwnode with the ACPI resources to get the client from
503 * @index: Index of ACPI resource to get
504 * @info: describes the I2C device; note this is modified (addr gets set)
505 * Context: can sleep
506 *
507 * By default the i2c subsys creates an i2c-client for the first I2cSerialBus
508 * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus
509 * resources, in that case this function can be used to create an i2c-client
510 * for other I2cSerialBus resources in the Current Resource Settings table.
511 *
512 * Also see i2c_new_client_device, which this function calls to create the
513 * i2c-client.
514 *
515 * Returns a pointer to the new i2c-client, or error pointer in case of failure.
516 * Specifically, -EPROBE_DEFER is returned if the adapter is not found.
517 */
i2c_acpi_new_device_by_fwnode(struct fwnode_handle * fwnode,int index,struct i2c_board_info * info)518 struct i2c_client *i2c_acpi_new_device_by_fwnode(struct fwnode_handle *fwnode,
519 int index,
520 struct i2c_board_info *info)
521 {
522 struct i2c_acpi_lookup lookup;
523 struct i2c_adapter *adapter;
524 struct acpi_device *adev;
525 LIST_HEAD(resource_list);
526 int ret;
527
528 adev = to_acpi_device_node(fwnode);
529 if (!adev)
530 return ERR_PTR(-ENODEV);
531
532 memset(&lookup, 0, sizeof(lookup));
533 lookup.info = info;
534 lookup.device_handle = acpi_device_handle(adev);
535 lookup.index = index;
536
537 ret = acpi_dev_get_resources(adev, &resource_list,
538 i2c_acpi_fill_info, &lookup);
539 if (ret < 0)
540 return ERR_PTR(ret);
541
542 acpi_dev_free_resource_list(&resource_list);
543
544 if (!info->addr)
545 return ERR_PTR(-EADDRNOTAVAIL);
546
547 adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle);
548 if (!adapter)
549 return ERR_PTR(-EPROBE_DEFER);
550
551 return i2c_new_client_device(adapter, info);
552 }
553 EXPORT_SYMBOL_GPL(i2c_acpi_new_device_by_fwnode);
554
i2c_acpi_waive_d0_probe(struct device * dev)555 bool i2c_acpi_waive_d0_probe(struct device *dev)
556 {
557 struct i2c_driver *driver = to_i2c_driver(dev->driver);
558 struct acpi_device *adev = ACPI_COMPANION(dev);
559
560 return driver->flags & I2C_DRV_ACPI_WAIVE_D0_PROBE &&
561 adev && adev->power.state_for_enumeration >= adev->power.state;
562 }
563 EXPORT_SYMBOL_GPL(i2c_acpi_waive_d0_probe);
564
565 #ifdef CONFIG_ACPI_I2C_OPREGION
acpi_gsb_i2c_read_bytes(struct i2c_client * client,u8 cmd,u8 * data,u8 data_len)566 static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
567 u8 cmd, u8 *data, u8 data_len)
568 {
569
570 struct i2c_msg msgs[2];
571 int ret;
572 u8 *buffer;
573
574 buffer = kzalloc(data_len, GFP_KERNEL);
575 if (!buffer)
576 return AE_NO_MEMORY;
577
578 msgs[0].addr = client->addr;
579 msgs[0].flags = client->flags;
580 msgs[0].len = 1;
581 msgs[0].buf = &cmd;
582
583 msgs[1].addr = client->addr;
584 msgs[1].flags = client->flags | I2C_M_RD;
585 msgs[1].len = data_len;
586 msgs[1].buf = buffer;
587
588 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
589 if (ret < 0) {
590 /* Getting a NACK is unfortunately normal with some DSTDs */
591 if (ret == -EREMOTEIO)
592 dev_dbg(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n",
593 data_len, client->addr, cmd, ret);
594 else
595 dev_err(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n",
596 data_len, client->addr, cmd, ret);
597 /* 2 transfers must have completed successfully */
598 } else if (ret == 2) {
599 memcpy(data, buffer, data_len);
600 ret = 0;
601 } else {
602 ret = -EIO;
603 }
604
605 kfree(buffer);
606 return ret;
607 }
608
acpi_gsb_i2c_write_bytes(struct i2c_client * client,u8 cmd,u8 * data,u8 data_len)609 static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
610 u8 cmd, u8 *data, u8 data_len)
611 {
612
613 struct i2c_msg msgs[1];
614 u8 *buffer;
615 int ret = AE_OK;
616
617 buffer = kzalloc(data_len + 1, GFP_KERNEL);
618 if (!buffer)
619 return AE_NO_MEMORY;
620
621 buffer[0] = cmd;
622 memcpy(buffer + 1, data, data_len);
623
624 msgs[0].addr = client->addr;
625 msgs[0].flags = client->flags;
626 msgs[0].len = data_len + 1;
627 msgs[0].buf = buffer;
628
629 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
630
631 kfree(buffer);
632
633 if (ret < 0) {
634 dev_err(&client->adapter->dev, "i2c write failed: %d\n", ret);
635 return ret;
636 }
637
638 /* 1 transfer must have completed successfully */
639 return (ret == 1) ? 0 : -EIO;
640 }
641
642 static acpi_status
i2c_acpi_space_handler(u32 function,acpi_physical_address command,u32 bits,u64 * value64,void * handler_context,void * region_context)643 i2c_acpi_space_handler(u32 function, acpi_physical_address command,
644 u32 bits, u64 *value64,
645 void *handler_context, void *region_context)
646 {
647 struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
648 struct i2c_acpi_handler_data *data = handler_context;
649 struct acpi_connection_info *info = &data->info;
650 struct acpi_resource_i2c_serialbus *sb;
651 struct i2c_adapter *adapter = data->adapter;
652 struct i2c_client *client;
653 struct acpi_resource *ares;
654 u32 accessor_type = function >> 16;
655 u8 action = function & ACPI_IO_MASK;
656 acpi_status ret;
657 int status;
658
659 ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
660 if (ACPI_FAILURE(ret))
661 return ret;
662
663 client = kzalloc(sizeof(*client), GFP_KERNEL);
664 if (!client) {
665 ret = AE_NO_MEMORY;
666 goto err;
667 }
668
669 if (!value64 || !i2c_acpi_get_i2c_resource(ares, &sb)) {
670 ret = AE_BAD_PARAMETER;
671 goto err;
672 }
673
674 client->adapter = adapter;
675 client->addr = sb->slave_address;
676
677 if (sb->access_mode == ACPI_I2C_10BIT_MODE)
678 client->flags |= I2C_CLIENT_TEN;
679
680 switch (accessor_type) {
681 case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
682 if (action == ACPI_READ) {
683 status = i2c_smbus_read_byte(client);
684 if (status >= 0) {
685 gsb->bdata = status;
686 status = 0;
687 }
688 } else {
689 status = i2c_smbus_write_byte(client, gsb->bdata);
690 }
691 break;
692
693 case ACPI_GSB_ACCESS_ATTRIB_BYTE:
694 if (action == ACPI_READ) {
695 status = i2c_smbus_read_byte_data(client, command);
696 if (status >= 0) {
697 gsb->bdata = status;
698 status = 0;
699 }
700 } else {
701 status = i2c_smbus_write_byte_data(client, command,
702 gsb->bdata);
703 }
704 break;
705
706 case ACPI_GSB_ACCESS_ATTRIB_WORD:
707 if (action == ACPI_READ) {
708 status = i2c_smbus_read_word_data(client, command);
709 if (status >= 0) {
710 gsb->wdata = status;
711 status = 0;
712 }
713 } else {
714 status = i2c_smbus_write_word_data(client, command,
715 gsb->wdata);
716 }
717 break;
718
719 case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
720 if (action == ACPI_READ) {
721 status = i2c_smbus_read_block_data(client, command,
722 gsb->data);
723 if (status >= 0) {
724 gsb->len = status;
725 status = 0;
726 }
727 } else {
728 status = i2c_smbus_write_block_data(client, command,
729 gsb->len, gsb->data);
730 }
731 break;
732
733 case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
734 if (action == ACPI_READ) {
735 status = acpi_gsb_i2c_read_bytes(client, command,
736 gsb->data, info->access_length);
737 } else {
738 status = acpi_gsb_i2c_write_bytes(client, command,
739 gsb->data, info->access_length);
740 }
741 break;
742
743 default:
744 dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n",
745 accessor_type, client->addr);
746 ret = AE_BAD_PARAMETER;
747 goto err;
748 }
749
750 gsb->status = status;
751
752 err:
753 kfree(client);
754 ACPI_FREE(ares);
755 return ret;
756 }
757
758
i2c_acpi_install_space_handler(struct i2c_adapter * adapter)759 int i2c_acpi_install_space_handler(struct i2c_adapter *adapter)
760 {
761 acpi_handle handle;
762 struct i2c_acpi_handler_data *data;
763 acpi_status status;
764
765 if (!adapter->dev.parent)
766 return -ENODEV;
767
768 handle = ACPI_HANDLE(adapter->dev.parent);
769
770 if (!handle)
771 return -ENODEV;
772
773 data = kzalloc(sizeof(struct i2c_acpi_handler_data),
774 GFP_KERNEL);
775 if (!data)
776 return -ENOMEM;
777
778 data->adapter = adapter;
779 status = acpi_bus_attach_private_data(handle, (void *)data);
780 if (ACPI_FAILURE(status)) {
781 kfree(data);
782 return -ENOMEM;
783 }
784
785 status = acpi_install_address_space_handler(handle,
786 ACPI_ADR_SPACE_GSBUS,
787 &i2c_acpi_space_handler,
788 NULL,
789 data);
790 if (ACPI_FAILURE(status)) {
791 dev_err(&adapter->dev, "Error installing i2c space handler\n");
792 acpi_bus_detach_private_data(handle);
793 kfree(data);
794 return -ENOMEM;
795 }
796
797 return 0;
798 }
799
i2c_acpi_remove_space_handler(struct i2c_adapter * adapter)800 void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter)
801 {
802 acpi_handle handle;
803 struct i2c_acpi_handler_data *data;
804 acpi_status status;
805
806 if (!adapter->dev.parent)
807 return;
808
809 handle = ACPI_HANDLE(adapter->dev.parent);
810
811 if (!handle)
812 return;
813
814 acpi_remove_address_space_handler(handle,
815 ACPI_ADR_SPACE_GSBUS,
816 &i2c_acpi_space_handler);
817
818 status = acpi_bus_get_private_data(handle, (void **)&data);
819 if (ACPI_SUCCESS(status))
820 kfree(data);
821
822 acpi_bus_detach_private_data(handle);
823 }
824 #endif /* CONFIG_ACPI_I2C_OPREGION */
825