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