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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
18struct i2c_acpi_handler_data {
19 struct acpi_connection_info info;
20 struct i2c_adapter *adapter;
21};
22
23struct 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
33struct 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 */
55bool 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}
70EXPORT_SYMBOL_GPL(i2c_acpi_get_i2c_resource);
71
72static 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 */
90int 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}
102EXPORT_SYMBOL_GPL(i2c_acpi_client_count);
103
104static 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
131static 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
140struct i2c_acpi_irq_context {
141 int irq;
142 bool wake_capable;
143};
144
145static 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
176static 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 */
202int 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
232static 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
277static 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
295static 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 */
320void 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
345static 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
358static 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 */
388u32 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}
424EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed);
425
426struct 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}
441EXPORT_SYMBOL_GPL(i2c_acpi_find_adapter_by_handle);
442
443static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
444{
445 struct device *dev;
446 struct i2c_client *client;
447
448 dev = bus_find_device_by_acpi_dev(&i2c_bus_type, adev);
449 if (!dev)
450 return NULL;
451
452 client = i2c_verify_client(dev);
453 if (!client)
454 put_device(dev);
455
456 return client;
457}
458
459static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
460 void *arg)
461{
462 struct acpi_device *adev = arg;
463 struct i2c_board_info info;
464 acpi_handle adapter_handle;
465 struct i2c_adapter *adapter;
466 struct i2c_client *client;
467
468 switch (value) {
469 case ACPI_RECONFIG_DEVICE_ADD:
470 if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle))
471 break;
472
473 adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
474 if (!adapter)
475 break;
476
477 i2c_acpi_register_device(adapter, adev, &info);
478 put_device(&adapter->dev);
479 break;
480 case ACPI_RECONFIG_DEVICE_REMOVE:
481 if (!acpi_device_enumerated(adev))
482 break;
483
484 client = i2c_acpi_find_client_by_adev(adev);
485 if (!client)
486 break;
487
488 i2c_unregister_device(client);
489 put_device(&client->dev);
490 break;
491 }
492
493 return NOTIFY_OK;
494}
495
496struct 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 */
518struct 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}
553EXPORT_SYMBOL_GPL(i2c_acpi_new_device_by_fwnode);
554
555bool 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}
563EXPORT_SYMBOL_GPL(i2c_acpi_waive_d0_probe);
564
565#ifdef CONFIG_ACPI_I2C_OPREGION
566static 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
609static 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
642static acpi_status
643i2c_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
759int 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
800void 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 */
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
18struct i2c_acpi_handler_data {
19 struct acpi_connection_info info;
20 struct i2c_adapter *adapter;
21};
22
23struct gsb_buffer {
24 u8 status;
25 u8 len;
26 union {
27 u16 wdata;
28 u8 bdata;
29 u8 data[0];
30 };
31} __packed;
32
33struct 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 */
55bool 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}
70EXPORT_SYMBOL_GPL(i2c_acpi_get_i2c_resource);
71
72static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data)
73{
74 struct i2c_acpi_lookup *lookup = data;
75 struct i2c_board_info *info = lookup->info;
76 struct acpi_resource_i2c_serialbus *sb;
77 acpi_status status;
78
79 if (info->addr || !i2c_acpi_get_i2c_resource(ares, &sb))
80 return 1;
81
82 if (lookup->index != -1 && lookup->n++ != lookup->index)
83 return 1;
84
85 status = acpi_get_handle(lookup->device_handle,
86 sb->resource_source.string_ptr,
87 &lookup->adapter_handle);
88 if (ACPI_FAILURE(status))
89 return 1;
90
91 info->addr = sb->slave_address;
92 lookup->speed = sb->connection_speed;
93 if (sb->access_mode == ACPI_I2C_10BIT_MODE)
94 info->flags |= I2C_CLIENT_TEN;
95
96 return 1;
97}
98
99static const struct acpi_device_id i2c_acpi_ignored_device_ids[] = {
100 /*
101 * ACPI video acpi_devices, which are handled by the acpi-video driver
102 * sometimes contain a SERIAL_TYPE_I2C ACPI resource, ignore these.
103 */
104 { ACPI_VIDEO_HID, 0 },
105 {}
106};
107
108static int i2c_acpi_do_lookup(struct acpi_device *adev,
109 struct i2c_acpi_lookup *lookup)
110{
111 struct i2c_board_info *info = lookup->info;
112 struct list_head resource_list;
113 int ret;
114
115 if (acpi_bus_get_status(adev) || !adev->status.present)
116 return -EINVAL;
117
118 if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0)
119 return -ENODEV;
120
121 memset(info, 0, sizeof(*info));
122 lookup->device_handle = acpi_device_handle(adev);
123
124 /* Look up for I2cSerialBus resource */
125 INIT_LIST_HEAD(&resource_list);
126 ret = acpi_dev_get_resources(adev, &resource_list,
127 i2c_acpi_fill_info, lookup);
128 acpi_dev_free_resource_list(&resource_list);
129
130 if (ret < 0 || !info->addr)
131 return -EINVAL;
132
133 return 0;
134}
135
136static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
137{
138 int *irq = data;
139 struct resource r;
140
141 if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
142 *irq = i2c_dev_irq_from_resources(&r, 1);
143
144 return 1; /* No need to add resource to the list */
145}
146
147/**
148 * i2c_acpi_get_irq - get device IRQ number from ACPI
149 * @client: Pointer to the I2C client device
150 *
151 * Find the IRQ number used by a specific client device.
152 *
153 * Return: The IRQ number or an error code.
154 */
155int i2c_acpi_get_irq(struct i2c_client *client)
156{
157 struct acpi_device *adev = ACPI_COMPANION(&client->dev);
158 struct list_head resource_list;
159 int irq = -ENOENT;
160 int ret;
161
162 INIT_LIST_HEAD(&resource_list);
163
164 ret = acpi_dev_get_resources(adev, &resource_list,
165 i2c_acpi_add_resource, &irq);
166 if (ret < 0)
167 return ret;
168
169 acpi_dev_free_resource_list(&resource_list);
170
171 if (irq == -ENOENT)
172 irq = acpi_dev_gpio_irq_get(adev, 0);
173
174 return irq;
175}
176
177static int i2c_acpi_get_info(struct acpi_device *adev,
178 struct i2c_board_info *info,
179 struct i2c_adapter *adapter,
180 acpi_handle *adapter_handle)
181{
182 struct i2c_acpi_lookup lookup;
183 int ret;
184
185 memset(&lookup, 0, sizeof(lookup));
186 lookup.info = info;
187 lookup.index = -1;
188
189 if (acpi_device_enumerated(adev))
190 return -EINVAL;
191
192 ret = i2c_acpi_do_lookup(adev, &lookup);
193 if (ret)
194 return ret;
195
196 if (adapter) {
197 /* The adapter must match the one in I2cSerialBus() connector */
198 if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle)
199 return -ENODEV;
200 } else {
201 struct acpi_device *adapter_adev;
202
203 /* The adapter must be present */
204 if (acpi_bus_get_device(lookup.adapter_handle, &adapter_adev))
205 return -ENODEV;
206 if (acpi_bus_get_status(adapter_adev) ||
207 !adapter_adev->status.present)
208 return -ENODEV;
209 }
210
211 info->fwnode = acpi_fwnode_handle(adev);
212 if (adapter_handle)
213 *adapter_handle = lookup.adapter_handle;
214
215 acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
216 sizeof(info->type));
217
218 return 0;
219}
220
221static void i2c_acpi_register_device(struct i2c_adapter *adapter,
222 struct acpi_device *adev,
223 struct i2c_board_info *info)
224{
225 adev->power.flags.ignore_parent = true;
226 acpi_device_set_enumerated(adev);
227
228 if (!i2c_new_device(adapter, info)) {
229 adev->power.flags.ignore_parent = false;
230 dev_err(&adapter->dev,
231 "failed to add I2C device %s from ACPI\n",
232 dev_name(&adev->dev));
233 }
234}
235
236static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
237 void *data, void **return_value)
238{
239 struct i2c_adapter *adapter = data;
240 struct acpi_device *adev;
241 struct i2c_board_info info;
242
243 if (acpi_bus_get_device(handle, &adev))
244 return AE_OK;
245
246 if (i2c_acpi_get_info(adev, &info, adapter, NULL))
247 return AE_OK;
248
249 i2c_acpi_register_device(adapter, adev, &info);
250
251 return AE_OK;
252}
253
254#define I2C_ACPI_MAX_SCAN_DEPTH 32
255
256/**
257 * i2c_acpi_register_devices - enumerate I2C slave devices behind adapter
258 * @adap: pointer to adapter
259 *
260 * Enumerate all I2C slave devices behind this adapter by walking the ACPI
261 * namespace. When a device is found it will be added to the Linux device
262 * model and bound to the corresponding ACPI handle.
263 */
264void i2c_acpi_register_devices(struct i2c_adapter *adap)
265{
266 acpi_status status;
267
268 if (!has_acpi_companion(&adap->dev))
269 return;
270
271 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
272 I2C_ACPI_MAX_SCAN_DEPTH,
273 i2c_acpi_add_device, NULL,
274 adap, NULL);
275 if (ACPI_FAILURE(status))
276 dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
277}
278
279const struct acpi_device_id *
280i2c_acpi_match_device(const struct acpi_device_id *matches,
281 struct i2c_client *client)
282{
283 if (!(client && matches))
284 return NULL;
285
286 return acpi_match_device(matches, &client->dev);
287}
288
289static const struct acpi_device_id i2c_acpi_force_400khz_device_ids[] = {
290 /*
291 * These Silead touchscreen controllers only work at 400KHz, for
292 * some reason they do not work at 100KHz. On some devices the ACPI
293 * tables list another device at their bus as only being capable
294 * of 100KHz, testing has shown that these other devices work fine
295 * at 400KHz (as can be expected of any recent i2c hw) so we force
296 * the speed of the bus to 400 KHz if a Silead device is present.
297 */
298 { "MSSL1680", 0 },
299 {}
300};
301
302static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level,
303 void *data, void **return_value)
304{
305 struct i2c_acpi_lookup *lookup = data;
306 struct acpi_device *adev;
307
308 if (acpi_bus_get_device(handle, &adev))
309 return AE_OK;
310
311 if (i2c_acpi_do_lookup(adev, lookup))
312 return AE_OK;
313
314 if (lookup->search_handle != lookup->adapter_handle)
315 return AE_OK;
316
317 if (lookup->speed <= lookup->min_speed)
318 lookup->min_speed = lookup->speed;
319
320 if (acpi_match_device_ids(adev, i2c_acpi_force_400khz_device_ids) == 0)
321 lookup->force_speed = 400000;
322
323 return AE_OK;
324}
325
326/**
327 * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI
328 * @dev: The device owning the bus
329 *
330 * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves
331 * devices connected to this bus and use the speed of slowest device.
332 *
333 * Returns the speed in Hz or zero
334 */
335u32 i2c_acpi_find_bus_speed(struct device *dev)
336{
337 struct i2c_acpi_lookup lookup;
338 struct i2c_board_info dummy;
339 acpi_status status;
340
341 if (!has_acpi_companion(dev))
342 return 0;
343
344 memset(&lookup, 0, sizeof(lookup));
345 lookup.search_handle = ACPI_HANDLE(dev);
346 lookup.min_speed = UINT_MAX;
347 lookup.info = &dummy;
348 lookup.index = -1;
349
350 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
351 I2C_ACPI_MAX_SCAN_DEPTH,
352 i2c_acpi_lookup_speed, NULL,
353 &lookup, NULL);
354
355 if (ACPI_FAILURE(status)) {
356 dev_warn(dev, "unable to find I2C bus speed from ACPI\n");
357 return 0;
358 }
359
360 if (lookup.force_speed) {
361 if (lookup.force_speed != lookup.min_speed)
362 dev_warn(dev, FW_BUG "DSDT uses known not-working I2C bus speed %d, forcing it to %d\n",
363 lookup.min_speed, lookup.force_speed);
364 return lookup.force_speed;
365 } else if (lookup.min_speed != UINT_MAX) {
366 return lookup.min_speed;
367 } else {
368 return 0;
369 }
370}
371EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed);
372
373static int i2c_acpi_find_match_adapter(struct device *dev, const void *data)
374{
375 struct i2c_adapter *adapter = i2c_verify_adapter(dev);
376
377 if (!adapter)
378 return 0;
379
380 return ACPI_HANDLE(dev) == (acpi_handle)data;
381}
382
383struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle)
384{
385 struct device *dev;
386
387 dev = bus_find_device(&i2c_bus_type, NULL, handle,
388 i2c_acpi_find_match_adapter);
389
390 return dev ? i2c_verify_adapter(dev) : NULL;
391}
392EXPORT_SYMBOL_GPL(i2c_acpi_find_adapter_by_handle);
393
394static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
395{
396 struct device *dev;
397
398 dev = bus_find_device_by_acpi_dev(&i2c_bus_type, adev);
399 return dev ? i2c_verify_client(dev) : NULL;
400}
401
402static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
403 void *arg)
404{
405 struct acpi_device *adev = arg;
406 struct i2c_board_info info;
407 acpi_handle adapter_handle;
408 struct i2c_adapter *adapter;
409 struct i2c_client *client;
410
411 switch (value) {
412 case ACPI_RECONFIG_DEVICE_ADD:
413 if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle))
414 break;
415
416 adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
417 if (!adapter)
418 break;
419
420 i2c_acpi_register_device(adapter, adev, &info);
421 break;
422 case ACPI_RECONFIG_DEVICE_REMOVE:
423 if (!acpi_device_enumerated(adev))
424 break;
425
426 client = i2c_acpi_find_client_by_adev(adev);
427 if (!client)
428 break;
429
430 i2c_unregister_device(client);
431 put_device(&client->dev);
432 break;
433 }
434
435 return NOTIFY_OK;
436}
437
438struct notifier_block i2c_acpi_notifier = {
439 .notifier_call = i2c_acpi_notify,
440};
441
442/**
443 * i2c_acpi_new_device - Create i2c-client for the Nth I2cSerialBus resource
444 * @dev: Device owning the ACPI resources to get the client from
445 * @index: Index of ACPI resource to get
446 * @info: describes the I2C device; note this is modified (addr gets set)
447 * Context: can sleep
448 *
449 * By default the i2c subsys creates an i2c-client for the first I2cSerialBus
450 * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus
451 * resources, in that case this function can be used to create an i2c-client
452 * for other I2cSerialBus resources in the Current Resource Settings table.
453 *
454 * Also see i2c_new_device, which this function calls to create the i2c-client.
455 *
456 * Returns a pointer to the new i2c-client, or error pointer in case of failure.
457 * Specifically, -EPROBE_DEFER is returned if the adapter is not found.
458 */
459struct i2c_client *i2c_acpi_new_device(struct device *dev, int index,
460 struct i2c_board_info *info)
461{
462 struct i2c_acpi_lookup lookup;
463 struct i2c_adapter *adapter;
464 struct i2c_client *client;
465 struct acpi_device *adev;
466 LIST_HEAD(resource_list);
467 int ret;
468
469 adev = ACPI_COMPANION(dev);
470 if (!adev)
471 return ERR_PTR(-EINVAL);
472
473 memset(&lookup, 0, sizeof(lookup));
474 lookup.info = info;
475 lookup.device_handle = acpi_device_handle(adev);
476 lookup.index = index;
477
478 ret = acpi_dev_get_resources(adev, &resource_list,
479 i2c_acpi_fill_info, &lookup);
480 if (ret < 0)
481 return ERR_PTR(ret);
482
483 acpi_dev_free_resource_list(&resource_list);
484
485 if (!info->addr)
486 return ERR_PTR(-EADDRNOTAVAIL);
487
488 adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle);
489 if (!adapter)
490 return ERR_PTR(-EPROBE_DEFER);
491
492 client = i2c_new_device(adapter, info);
493 if (!client)
494 return ERR_PTR(-ENODEV);
495
496 return client;
497}
498EXPORT_SYMBOL_GPL(i2c_acpi_new_device);
499
500#ifdef CONFIG_ACPI_I2C_OPREGION
501static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
502 u8 cmd, u8 *data, u8 data_len)
503{
504
505 struct i2c_msg msgs[2];
506 int ret;
507 u8 *buffer;
508
509 buffer = kzalloc(data_len, GFP_KERNEL);
510 if (!buffer)
511 return AE_NO_MEMORY;
512
513 msgs[0].addr = client->addr;
514 msgs[0].flags = client->flags;
515 msgs[0].len = 1;
516 msgs[0].buf = &cmd;
517
518 msgs[1].addr = client->addr;
519 msgs[1].flags = client->flags | I2C_M_RD;
520 msgs[1].len = data_len;
521 msgs[1].buf = buffer;
522
523 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
524 if (ret < 0) {
525 /* Getting a NACK is unfortunately normal with some DSTDs */
526 if (ret == -EREMOTEIO)
527 dev_dbg(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n",
528 data_len, client->addr, cmd, ret);
529 else
530 dev_err(&client->adapter->dev, "i2c read %d bytes from client@%#x starting at reg %#x failed, error: %d\n",
531 data_len, client->addr, cmd, ret);
532 /* 2 transfers must have completed successfully */
533 } else if (ret == 2) {
534 memcpy(data, buffer, data_len);
535 ret = 0;
536 } else {
537 ret = -EIO;
538 }
539
540 kfree(buffer);
541 return ret;
542}
543
544static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
545 u8 cmd, u8 *data, u8 data_len)
546{
547
548 struct i2c_msg msgs[1];
549 u8 *buffer;
550 int ret = AE_OK;
551
552 buffer = kzalloc(data_len + 1, GFP_KERNEL);
553 if (!buffer)
554 return AE_NO_MEMORY;
555
556 buffer[0] = cmd;
557 memcpy(buffer + 1, data, data_len);
558
559 msgs[0].addr = client->addr;
560 msgs[0].flags = client->flags;
561 msgs[0].len = data_len + 1;
562 msgs[0].buf = buffer;
563
564 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
565
566 kfree(buffer);
567
568 if (ret < 0) {
569 dev_err(&client->adapter->dev, "i2c write failed: %d\n", ret);
570 return ret;
571 }
572
573 /* 1 transfer must have completed successfully */
574 return (ret == 1) ? 0 : -EIO;
575}
576
577static acpi_status
578i2c_acpi_space_handler(u32 function, acpi_physical_address command,
579 u32 bits, u64 *value64,
580 void *handler_context, void *region_context)
581{
582 struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
583 struct i2c_acpi_handler_data *data = handler_context;
584 struct acpi_connection_info *info = &data->info;
585 struct acpi_resource_i2c_serialbus *sb;
586 struct i2c_adapter *adapter = data->adapter;
587 struct i2c_client *client;
588 struct acpi_resource *ares;
589 u32 accessor_type = function >> 16;
590 u8 action = function & ACPI_IO_MASK;
591 acpi_status ret;
592 int status;
593
594 ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
595 if (ACPI_FAILURE(ret))
596 return ret;
597
598 client = kzalloc(sizeof(*client), GFP_KERNEL);
599 if (!client) {
600 ret = AE_NO_MEMORY;
601 goto err;
602 }
603
604 if (!value64 || !i2c_acpi_get_i2c_resource(ares, &sb)) {
605 ret = AE_BAD_PARAMETER;
606 goto err;
607 }
608
609 client->adapter = adapter;
610 client->addr = sb->slave_address;
611
612 if (sb->access_mode == ACPI_I2C_10BIT_MODE)
613 client->flags |= I2C_CLIENT_TEN;
614
615 switch (accessor_type) {
616 case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
617 if (action == ACPI_READ) {
618 status = i2c_smbus_read_byte(client);
619 if (status >= 0) {
620 gsb->bdata = status;
621 status = 0;
622 }
623 } else {
624 status = i2c_smbus_write_byte(client, gsb->bdata);
625 }
626 break;
627
628 case ACPI_GSB_ACCESS_ATTRIB_BYTE:
629 if (action == ACPI_READ) {
630 status = i2c_smbus_read_byte_data(client, command);
631 if (status >= 0) {
632 gsb->bdata = status;
633 status = 0;
634 }
635 } else {
636 status = i2c_smbus_write_byte_data(client, command,
637 gsb->bdata);
638 }
639 break;
640
641 case ACPI_GSB_ACCESS_ATTRIB_WORD:
642 if (action == ACPI_READ) {
643 status = i2c_smbus_read_word_data(client, command);
644 if (status >= 0) {
645 gsb->wdata = status;
646 status = 0;
647 }
648 } else {
649 status = i2c_smbus_write_word_data(client, command,
650 gsb->wdata);
651 }
652 break;
653
654 case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
655 if (action == ACPI_READ) {
656 status = i2c_smbus_read_block_data(client, command,
657 gsb->data);
658 if (status >= 0) {
659 gsb->len = status;
660 status = 0;
661 }
662 } else {
663 status = i2c_smbus_write_block_data(client, command,
664 gsb->len, gsb->data);
665 }
666 break;
667
668 case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
669 if (action == ACPI_READ) {
670 status = acpi_gsb_i2c_read_bytes(client, command,
671 gsb->data, info->access_length);
672 } else {
673 status = acpi_gsb_i2c_write_bytes(client, command,
674 gsb->data, info->access_length);
675 }
676 break;
677
678 default:
679 dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n",
680 accessor_type, client->addr);
681 ret = AE_BAD_PARAMETER;
682 goto err;
683 }
684
685 gsb->status = status;
686
687 err:
688 kfree(client);
689 ACPI_FREE(ares);
690 return ret;
691}
692
693
694int i2c_acpi_install_space_handler(struct i2c_adapter *adapter)
695{
696 acpi_handle handle;
697 struct i2c_acpi_handler_data *data;
698 acpi_status status;
699
700 if (!adapter->dev.parent)
701 return -ENODEV;
702
703 handle = ACPI_HANDLE(adapter->dev.parent);
704
705 if (!handle)
706 return -ENODEV;
707
708 data = kzalloc(sizeof(struct i2c_acpi_handler_data),
709 GFP_KERNEL);
710 if (!data)
711 return -ENOMEM;
712
713 data->adapter = adapter;
714 status = acpi_bus_attach_private_data(handle, (void *)data);
715 if (ACPI_FAILURE(status)) {
716 kfree(data);
717 return -ENOMEM;
718 }
719
720 status = acpi_install_address_space_handler(handle,
721 ACPI_ADR_SPACE_GSBUS,
722 &i2c_acpi_space_handler,
723 NULL,
724 data);
725 if (ACPI_FAILURE(status)) {
726 dev_err(&adapter->dev, "Error installing i2c space handler\n");
727 acpi_bus_detach_private_data(handle);
728 kfree(data);
729 return -ENOMEM;
730 }
731
732 acpi_walk_dep_device_list(handle);
733 return 0;
734}
735
736void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter)
737{
738 acpi_handle handle;
739 struct i2c_acpi_handler_data *data;
740 acpi_status status;
741
742 if (!adapter->dev.parent)
743 return;
744
745 handle = ACPI_HANDLE(adapter->dev.parent);
746
747 if (!handle)
748 return;
749
750 acpi_remove_address_space_handler(handle,
751 ACPI_ADR_SPACE_GSBUS,
752 &i2c_acpi_space_handler);
753
754 status = acpi_bus_get_private_data(handle, (void **)&data);
755 if (ACPI_SUCCESS(status))
756 kfree(data);
757
758 acpi_bus_detach_private_data(handle);
759}
760#endif /* CONFIG_ACPI_I2C_OPREGION */