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 u8 data[0];
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
i2c_acpi_do_lookup(struct acpi_device * adev,struct i2c_acpi_lookup * lookup)140 static int i2c_acpi_do_lookup(struct acpi_device *adev,
141 struct i2c_acpi_lookup *lookup)
142 {
143 struct i2c_board_info *info = lookup->info;
144 struct list_head resource_list;
145 int ret;
146
147 if (acpi_bus_get_status(adev) || !adev->status.present)
148 return -EINVAL;
149
150 if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0)
151 return -ENODEV;
152
153 memset(info, 0, sizeof(*info));
154 lookup->device_handle = acpi_device_handle(adev);
155
156 /* Look up for I2cSerialBus resource */
157 INIT_LIST_HEAD(&resource_list);
158 ret = acpi_dev_get_resources(adev, &resource_list,
159 i2c_acpi_fill_info, lookup);
160 acpi_dev_free_resource_list(&resource_list);
161
162 if (ret < 0 || !info->addr)
163 return -EINVAL;
164
165 return 0;
166 }
167
i2c_acpi_add_resource(struct acpi_resource * ares,void * data)168 static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
169 {
170 int *irq = data;
171 struct resource r;
172
173 if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
174 *irq = i2c_dev_irq_from_resources(&r, 1);
175
176 return 1; /* No need to add resource to the list */
177 }
178
179 /**
180 * i2c_acpi_get_irq - get device IRQ number from ACPI
181 * @client: Pointer to the I2C client device
182 *
183 * Find the IRQ number used by a specific client device.
184 *
185 * Return: The IRQ number or an error code.
186 */
i2c_acpi_get_irq(struct i2c_client * client)187 int i2c_acpi_get_irq(struct i2c_client *client)
188 {
189 struct acpi_device *adev = ACPI_COMPANION(&client->dev);
190 struct list_head resource_list;
191 int irq = -ENOENT;
192 int ret;
193
194 INIT_LIST_HEAD(&resource_list);
195
196 ret = acpi_dev_get_resources(adev, &resource_list,
197 i2c_acpi_add_resource, &irq);
198 if (ret < 0)
199 return ret;
200
201 acpi_dev_free_resource_list(&resource_list);
202
203 if (irq == -ENOENT)
204 irq = acpi_dev_gpio_irq_get(adev, 0);
205
206 return irq;
207 }
208
i2c_acpi_get_info(struct acpi_device * adev,struct i2c_board_info * info,struct i2c_adapter * adapter,acpi_handle * adapter_handle)209 static int i2c_acpi_get_info(struct acpi_device *adev,
210 struct i2c_board_info *info,
211 struct i2c_adapter *adapter,
212 acpi_handle *adapter_handle)
213 {
214 struct i2c_acpi_lookup lookup;
215 int ret;
216
217 memset(&lookup, 0, sizeof(lookup));
218 lookup.info = info;
219 lookup.index = -1;
220
221 if (acpi_device_enumerated(adev))
222 return -EINVAL;
223
224 ret = i2c_acpi_do_lookup(adev, &lookup);
225 if (ret)
226 return ret;
227
228 if (adapter) {
229 /* The adapter must match the one in I2cSerialBus() connector */
230 if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle)
231 return -ENODEV;
232 } else {
233 struct acpi_device *adapter_adev;
234
235 /* The adapter must be present */
236 if (acpi_bus_get_device(lookup.adapter_handle, &adapter_adev))
237 return -ENODEV;
238 if (acpi_bus_get_status(adapter_adev) ||
239 !adapter_adev->status.present)
240 return -ENODEV;
241 }
242
243 info->fwnode = acpi_fwnode_handle(adev);
244 if (adapter_handle)
245 *adapter_handle = lookup.adapter_handle;
246
247 acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
248 sizeof(info->type));
249
250 return 0;
251 }
252
i2c_acpi_register_device(struct i2c_adapter * adapter,struct acpi_device * adev,struct i2c_board_info * info)253 static void i2c_acpi_register_device(struct i2c_adapter *adapter,
254 struct acpi_device *adev,
255 struct i2c_board_info *info)
256 {
257 adev->power.flags.ignore_parent = true;
258 acpi_device_set_enumerated(adev);
259
260 if (IS_ERR(i2c_new_client_device(adapter, info)))
261 adev->power.flags.ignore_parent = false;
262 }
263
i2c_acpi_add_device(acpi_handle handle,u32 level,void * data,void ** return_value)264 static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
265 void *data, void **return_value)
266 {
267 struct i2c_adapter *adapter = data;
268 struct acpi_device *adev;
269 struct i2c_board_info info;
270
271 if (acpi_bus_get_device(handle, &adev))
272 return AE_OK;
273
274 if (i2c_acpi_get_info(adev, &info, adapter, NULL))
275 return AE_OK;
276
277 i2c_acpi_register_device(adapter, adev, &info);
278
279 return AE_OK;
280 }
281
282 #define I2C_ACPI_MAX_SCAN_DEPTH 32
283
284 /**
285 * i2c_acpi_register_devices - enumerate I2C slave devices behind adapter
286 * @adap: pointer to adapter
287 *
288 * Enumerate all I2C slave devices behind this adapter by walking the ACPI
289 * namespace. When a device is found it will be added to the Linux device
290 * model and bound to the corresponding ACPI handle.
291 */
i2c_acpi_register_devices(struct i2c_adapter * adap)292 void i2c_acpi_register_devices(struct i2c_adapter *adap)
293 {
294 struct acpi_device *adev;
295 acpi_status status;
296
297 if (!has_acpi_companion(&adap->dev))
298 return;
299
300 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
301 I2C_ACPI_MAX_SCAN_DEPTH,
302 i2c_acpi_add_device, NULL,
303 adap, NULL);
304 if (ACPI_FAILURE(status))
305 dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
306
307 if (!adap->dev.parent)
308 return;
309
310 adev = ACPI_COMPANION(adap->dev.parent);
311 if (!adev)
312 return;
313
314 acpi_dev_clear_dependencies(adev);
315 }
316
317 static const struct acpi_device_id i2c_acpi_force_400khz_device_ids[] = {
318 /*
319 * These Silead touchscreen controllers only work at 400KHz, for
320 * some reason they do not work at 100KHz. On some devices the ACPI
321 * tables list another device at their bus as only being capable
322 * of 100KHz, testing has shown that these other devices work fine
323 * at 400KHz (as can be expected of any recent i2c hw) so we force
324 * the speed of the bus to 400 KHz if a Silead device is present.
325 */
326 { "MSSL1680", 0 },
327 {}
328 };
329
i2c_acpi_lookup_speed(acpi_handle handle,u32 level,void * data,void ** return_value)330 static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level,
331 void *data, void **return_value)
332 {
333 struct i2c_acpi_lookup *lookup = data;
334 struct acpi_device *adev;
335
336 if (acpi_bus_get_device(handle, &adev))
337 return AE_OK;
338
339 if (i2c_acpi_do_lookup(adev, lookup))
340 return AE_OK;
341
342 if (lookup->search_handle != lookup->adapter_handle)
343 return AE_OK;
344
345 if (lookup->speed <= lookup->min_speed)
346 lookup->min_speed = lookup->speed;
347
348 if (acpi_match_device_ids(adev, i2c_acpi_force_400khz_device_ids) == 0)
349 lookup->force_speed = I2C_MAX_FAST_MODE_FREQ;
350
351 return AE_OK;
352 }
353
354 /**
355 * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI
356 * @dev: The device owning the bus
357 *
358 * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves
359 * devices connected to this bus and use the speed of slowest device.
360 *
361 * Returns the speed in Hz or zero
362 */
i2c_acpi_find_bus_speed(struct device * dev)363 u32 i2c_acpi_find_bus_speed(struct device *dev)
364 {
365 struct i2c_acpi_lookup lookup;
366 struct i2c_board_info dummy;
367 acpi_status status;
368
369 if (!has_acpi_companion(dev))
370 return 0;
371
372 memset(&lookup, 0, sizeof(lookup));
373 lookup.search_handle = ACPI_HANDLE(dev);
374 lookup.min_speed = UINT_MAX;
375 lookup.info = &dummy;
376 lookup.index = -1;
377
378 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
379 I2C_ACPI_MAX_SCAN_DEPTH,
380 i2c_acpi_lookup_speed, NULL,
381 &lookup, NULL);
382
383 if (ACPI_FAILURE(status)) {
384 dev_warn(dev, "unable to find I2C bus speed from ACPI\n");
385 return 0;
386 }
387
388 if (lookup.force_speed) {
389 if (lookup.force_speed != lookup.min_speed)
390 dev_warn(dev, FW_BUG "DSDT uses known not-working I2C bus speed %d, forcing it to %d\n",
391 lookup.min_speed, lookup.force_speed);
392 return lookup.force_speed;
393 } else if (lookup.min_speed != UINT_MAX) {
394 return lookup.min_speed;
395 } else {
396 return 0;
397 }
398 }
399 EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed);
400
i2c_acpi_find_match_adapter(struct device * dev,const void * data)401 static int i2c_acpi_find_match_adapter(struct device *dev, const void *data)
402 {
403 struct i2c_adapter *adapter = i2c_verify_adapter(dev);
404
405 if (!adapter)
406 return 0;
407
408 return ACPI_HANDLE(dev) == (acpi_handle)data;
409 }
410
i2c_acpi_find_adapter_by_handle(acpi_handle handle)411 struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle)
412 {
413 struct device *dev;
414
415 dev = bus_find_device(&i2c_bus_type, NULL, handle,
416 i2c_acpi_find_match_adapter);
417
418 return dev ? i2c_verify_adapter(dev) : NULL;
419 }
420 EXPORT_SYMBOL_GPL(i2c_acpi_find_adapter_by_handle);
421
i2c_acpi_find_client_by_adev(struct acpi_device * adev)422 static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
423 {
424 struct device *dev;
425 struct i2c_client *client;
426
427 dev = bus_find_device_by_acpi_dev(&i2c_bus_type, adev);
428 if (!dev)
429 return NULL;
430
431 client = i2c_verify_client(dev);
432 if (!client)
433 put_device(dev);
434
435 return client;
436 }
437
i2c_acpi_notify(struct notifier_block * nb,unsigned long value,void * arg)438 static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
439 void *arg)
440 {
441 struct acpi_device *adev = arg;
442 struct i2c_board_info info;
443 acpi_handle adapter_handle;
444 struct i2c_adapter *adapter;
445 struct i2c_client *client;
446
447 switch (value) {
448 case ACPI_RECONFIG_DEVICE_ADD:
449 if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle))
450 break;
451
452 adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
453 if (!adapter)
454 break;
455
456 i2c_acpi_register_device(adapter, adev, &info);
457 put_device(&adapter->dev);
458 break;
459 case ACPI_RECONFIG_DEVICE_REMOVE:
460 if (!acpi_device_enumerated(adev))
461 break;
462
463 client = i2c_acpi_find_client_by_adev(adev);
464 if (!client)
465 break;
466
467 i2c_unregister_device(client);
468 put_device(&client->dev);
469 break;
470 }
471
472 return NOTIFY_OK;
473 }
474
475 struct notifier_block i2c_acpi_notifier = {
476 .notifier_call = i2c_acpi_notify,
477 };
478
479 /**
480 * i2c_acpi_new_device - Create i2c-client for the Nth I2cSerialBus resource
481 * @dev: Device owning the ACPI resources to get the client from
482 * @index: Index of ACPI resource to get
483 * @info: describes the I2C device; note this is modified (addr gets set)
484 * Context: can sleep
485 *
486 * By default the i2c subsys creates an i2c-client for the first I2cSerialBus
487 * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus
488 * resources, in that case this function can be used to create an i2c-client
489 * for other I2cSerialBus resources in the Current Resource Settings table.
490 *
491 * Also see i2c_new_client_device, which this function calls to create the
492 * i2c-client.
493 *
494 * Returns a pointer to the new i2c-client, or error pointer in case of failure.
495 * Specifically, -EPROBE_DEFER is returned if the adapter is not found.
496 */
i2c_acpi_new_device(struct device * dev,int index,struct i2c_board_info * info)497 struct i2c_client *i2c_acpi_new_device(struct device *dev, int index,
498 struct i2c_board_info *info)
499 {
500 struct acpi_device *adev = ACPI_COMPANION(dev);
501 struct i2c_acpi_lookup lookup;
502 struct i2c_adapter *adapter;
503 LIST_HEAD(resource_list);
504 int ret;
505
506 memset(&lookup, 0, sizeof(lookup));
507 lookup.info = info;
508 lookup.device_handle = acpi_device_handle(adev);
509 lookup.index = index;
510
511 ret = acpi_dev_get_resources(adev, &resource_list,
512 i2c_acpi_fill_info, &lookup);
513 if (ret < 0)
514 return ERR_PTR(ret);
515
516 acpi_dev_free_resource_list(&resource_list);
517
518 if (!info->addr)
519 return ERR_PTR(-EADDRNOTAVAIL);
520
521 adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle);
522 if (!adapter)
523 return ERR_PTR(-EPROBE_DEFER);
524
525 return i2c_new_client_device(adapter, info);
526 }
527 EXPORT_SYMBOL_GPL(i2c_acpi_new_device);
528
529 #ifdef CONFIG_ACPI_I2C_OPREGION
acpi_gsb_i2c_read_bytes(struct i2c_client * client,u8 cmd,u8 * data,u8 data_len)530 static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
531 u8 cmd, u8 *data, u8 data_len)
532 {
533
534 struct i2c_msg msgs[2];
535 int ret;
536 u8 *buffer;
537
538 buffer = kzalloc(data_len, GFP_KERNEL);
539 if (!buffer)
540 return AE_NO_MEMORY;
541
542 msgs[0].addr = client->addr;
543 msgs[0].flags = client->flags;
544 msgs[0].len = 1;
545 msgs[0].buf = &cmd;
546
547 msgs[1].addr = client->addr;
548 msgs[1].flags = client->flags | I2C_M_RD;
549 msgs[1].len = data_len;
550 msgs[1].buf = buffer;
551
552 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
553 if (ret < 0) {
554 /* Getting a NACK is unfortunately normal with some DSTDs */
555 if (ret == -EREMOTEIO)
556 dev_dbg(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n",
557 data_len, client->addr, cmd, ret);
558 else
559 dev_err(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n",
560 data_len, client->addr, cmd, ret);
561 /* 2 transfers must have completed successfully */
562 } else if (ret == 2) {
563 memcpy(data, buffer, data_len);
564 ret = 0;
565 } else {
566 ret = -EIO;
567 }
568
569 kfree(buffer);
570 return ret;
571 }
572
acpi_gsb_i2c_write_bytes(struct i2c_client * client,u8 cmd,u8 * data,u8 data_len)573 static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
574 u8 cmd, u8 *data, u8 data_len)
575 {
576
577 struct i2c_msg msgs[1];
578 u8 *buffer;
579 int ret = AE_OK;
580
581 buffer = kzalloc(data_len + 1, GFP_KERNEL);
582 if (!buffer)
583 return AE_NO_MEMORY;
584
585 buffer[0] = cmd;
586 memcpy(buffer + 1, data, data_len);
587
588 msgs[0].addr = client->addr;
589 msgs[0].flags = client->flags;
590 msgs[0].len = data_len + 1;
591 msgs[0].buf = buffer;
592
593 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
594
595 kfree(buffer);
596
597 if (ret < 0) {
598 dev_err(&client->adapter->dev, "i2c write failed: %d\n", ret);
599 return ret;
600 }
601
602 /* 1 transfer must have completed successfully */
603 return (ret == 1) ? 0 : -EIO;
604 }
605
606 static acpi_status
i2c_acpi_space_handler(u32 function,acpi_physical_address command,u32 bits,u64 * value64,void * handler_context,void * region_context)607 i2c_acpi_space_handler(u32 function, acpi_physical_address command,
608 u32 bits, u64 *value64,
609 void *handler_context, void *region_context)
610 {
611 struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
612 struct i2c_acpi_handler_data *data = handler_context;
613 struct acpi_connection_info *info = &data->info;
614 struct acpi_resource_i2c_serialbus *sb;
615 struct i2c_adapter *adapter = data->adapter;
616 struct i2c_client *client;
617 struct acpi_resource *ares;
618 u32 accessor_type = function >> 16;
619 u8 action = function & ACPI_IO_MASK;
620 acpi_status ret;
621 int status;
622
623 ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
624 if (ACPI_FAILURE(ret))
625 return ret;
626
627 client = kzalloc(sizeof(*client), GFP_KERNEL);
628 if (!client) {
629 ret = AE_NO_MEMORY;
630 goto err;
631 }
632
633 if (!value64 || !i2c_acpi_get_i2c_resource(ares, &sb)) {
634 ret = AE_BAD_PARAMETER;
635 goto err;
636 }
637
638 client->adapter = adapter;
639 client->addr = sb->slave_address;
640
641 if (sb->access_mode == ACPI_I2C_10BIT_MODE)
642 client->flags |= I2C_CLIENT_TEN;
643
644 switch (accessor_type) {
645 case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
646 if (action == ACPI_READ) {
647 status = i2c_smbus_read_byte(client);
648 if (status >= 0) {
649 gsb->bdata = status;
650 status = 0;
651 }
652 } else {
653 status = i2c_smbus_write_byte(client, gsb->bdata);
654 }
655 break;
656
657 case ACPI_GSB_ACCESS_ATTRIB_BYTE:
658 if (action == ACPI_READ) {
659 status = i2c_smbus_read_byte_data(client, command);
660 if (status >= 0) {
661 gsb->bdata = status;
662 status = 0;
663 }
664 } else {
665 status = i2c_smbus_write_byte_data(client, command,
666 gsb->bdata);
667 }
668 break;
669
670 case ACPI_GSB_ACCESS_ATTRIB_WORD:
671 if (action == ACPI_READ) {
672 status = i2c_smbus_read_word_data(client, command);
673 if (status >= 0) {
674 gsb->wdata = status;
675 status = 0;
676 }
677 } else {
678 status = i2c_smbus_write_word_data(client, command,
679 gsb->wdata);
680 }
681 break;
682
683 case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
684 if (action == ACPI_READ) {
685 status = i2c_smbus_read_block_data(client, command,
686 gsb->data);
687 if (status >= 0) {
688 gsb->len = status;
689 status = 0;
690 }
691 } else {
692 status = i2c_smbus_write_block_data(client, command,
693 gsb->len, gsb->data);
694 }
695 break;
696
697 case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
698 if (action == ACPI_READ) {
699 status = acpi_gsb_i2c_read_bytes(client, command,
700 gsb->data, info->access_length);
701 } else {
702 status = acpi_gsb_i2c_write_bytes(client, command,
703 gsb->data, info->access_length);
704 }
705 break;
706
707 default:
708 dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n",
709 accessor_type, client->addr);
710 ret = AE_BAD_PARAMETER;
711 goto err;
712 }
713
714 gsb->status = status;
715
716 err:
717 kfree(client);
718 ACPI_FREE(ares);
719 return ret;
720 }
721
722
i2c_acpi_install_space_handler(struct i2c_adapter * adapter)723 int i2c_acpi_install_space_handler(struct i2c_adapter *adapter)
724 {
725 acpi_handle handle;
726 struct i2c_acpi_handler_data *data;
727 acpi_status status;
728
729 if (!adapter->dev.parent)
730 return -ENODEV;
731
732 handle = ACPI_HANDLE(adapter->dev.parent);
733
734 if (!handle)
735 return -ENODEV;
736
737 data = kzalloc(sizeof(struct i2c_acpi_handler_data),
738 GFP_KERNEL);
739 if (!data)
740 return -ENOMEM;
741
742 data->adapter = adapter;
743 status = acpi_bus_attach_private_data(handle, (void *)data);
744 if (ACPI_FAILURE(status)) {
745 kfree(data);
746 return -ENOMEM;
747 }
748
749 status = acpi_install_address_space_handler(handle,
750 ACPI_ADR_SPACE_GSBUS,
751 &i2c_acpi_space_handler,
752 NULL,
753 data);
754 if (ACPI_FAILURE(status)) {
755 dev_err(&adapter->dev, "Error installing i2c space handler\n");
756 acpi_bus_detach_private_data(handle);
757 kfree(data);
758 return -ENOMEM;
759 }
760
761 return 0;
762 }
763
i2c_acpi_remove_space_handler(struct i2c_adapter * adapter)764 void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter)
765 {
766 acpi_handle handle;
767 struct i2c_acpi_handler_data *data;
768 acpi_status status;
769
770 if (!adapter->dev.parent)
771 return;
772
773 handle = ACPI_HANDLE(adapter->dev.parent);
774
775 if (!handle)
776 return;
777
778 acpi_remove_address_space_handler(handle,
779 ACPI_ADR_SPACE_GSBUS,
780 &i2c_acpi_space_handler);
781
782 status = acpi_bus_get_private_data(handle, (void **)&data);
783 if (ACPI_SUCCESS(status))
784 kfree(data);
785
786 acpi_bus_detach_private_data(handle);
787 }
788 #endif /* CONFIG_ACPI_I2C_OPREGION */
789