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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * SMBus driver for ACPI SMBus CMI
  4 *
  5 * Copyright (C) 2009 Crane Cai <crane.cai@amd.com>
 
 
 
 
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/platform_device.h>
 10#include <linux/slab.h>
 11#include <linux/kernel.h>
 12#include <linux/stddef.h>
 13#include <linux/i2c.h>
 14#include <linux/acpi.h>
 15
 
 
 
 16/* SMBUS HID definition as supported by Microsoft Windows */
 17#define ACPI_SMBUS_MS_HID		"SMB0001"
 18
 
 
 19struct smbus_methods_t {
 20	char *mt_info;
 21	char *mt_sbr;
 22	char *mt_sbw;
 23};
 24
 25struct acpi_smbus_cmi {
 26	acpi_handle handle;
 27	struct i2c_adapter adapter;
 28	u8 cap_info:1;
 29	u8 cap_read:1;
 30	u8 cap_write:1;
 31	const struct smbus_methods_t *methods;
 32};
 33
 34static const struct smbus_methods_t smbus_methods = {
 35	.mt_info = "_SBI",
 36	.mt_sbr  = "_SBR",
 37	.mt_sbw  = "_SBW",
 38};
 39
 40/* Some IBM BIOSes omit the leading underscore */
 41static const struct smbus_methods_t ibm_smbus_methods = {
 42	.mt_info = "SBI_",
 43	.mt_sbr  = "SBR_",
 44	.mt_sbw  = "SBW_",
 45};
 46
 47static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
 48	{"SMBUS01", (kernel_ulong_t)&smbus_methods},
 49	{ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods},
 50	{ACPI_SMBUS_MS_HID, (kernel_ulong_t)&smbus_methods},
 51	{"", 0}
 52};
 53MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids);
 54
 55#define ACPI_SMBUS_STATUS_OK			0x00
 56#define ACPI_SMBUS_STATUS_FAIL			0x07
 57#define ACPI_SMBUS_STATUS_DNAK			0x10
 58#define ACPI_SMBUS_STATUS_DERR			0x11
 59#define ACPI_SMBUS_STATUS_CMD_DENY		0x12
 60#define ACPI_SMBUS_STATUS_UNKNOWN		0x13
 61#define ACPI_SMBUS_STATUS_ACC_DENY		0x17
 62#define ACPI_SMBUS_STATUS_TIMEOUT		0x18
 63#define ACPI_SMBUS_STATUS_NOTSUP		0x19
 64#define ACPI_SMBUS_STATUS_BUSY			0x1a
 65#define ACPI_SMBUS_STATUS_PEC			0x1f
 66
 67#define ACPI_SMBUS_PRTCL_WRITE			0x00
 68#define ACPI_SMBUS_PRTCL_READ			0x01
 69#define ACPI_SMBUS_PRTCL_QUICK			0x02
 70#define ACPI_SMBUS_PRTCL_BYTE			0x04
 71#define ACPI_SMBUS_PRTCL_BYTE_DATA		0x06
 72#define ACPI_SMBUS_PRTCL_WORD_DATA		0x08
 73#define ACPI_SMBUS_PRTCL_BLOCK_DATA		0x0a
 74
 75
 76static int
 77acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
 78		   char read_write, u8 command, int size,
 79		   union i2c_smbus_data *data)
 80{
 81	int result = 0;
 82	struct acpi_smbus_cmi *smbus_cmi = adap->algo_data;
 83	unsigned char protocol;
 84	acpi_status status = 0;
 85	struct acpi_object_list input;
 86	union acpi_object mt_params[5];
 87	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 88	union acpi_object *obj;
 89	union acpi_object *pkg;
 90	char *method;
 91	int len = 0;
 92
 93	dev_dbg(&adap->dev, "access size: %d %s\n", size,
 94		(read_write) ? "READ" : "WRITE");
 95	switch (size) {
 96	case I2C_SMBUS_QUICK:
 97		protocol = ACPI_SMBUS_PRTCL_QUICK;
 98		command = 0;
 99		if (read_write == I2C_SMBUS_WRITE) {
100			mt_params[3].type = ACPI_TYPE_INTEGER;
101			mt_params[3].integer.value = 0;
102			mt_params[4].type = ACPI_TYPE_INTEGER;
103			mt_params[4].integer.value = 0;
104		}
105		break;
106
107	case I2C_SMBUS_BYTE:
108		protocol = ACPI_SMBUS_PRTCL_BYTE;
109		if (read_write == I2C_SMBUS_WRITE) {
110			mt_params[3].type = ACPI_TYPE_INTEGER;
111			mt_params[3].integer.value = 0;
112			mt_params[4].type = ACPI_TYPE_INTEGER;
113			mt_params[4].integer.value = 0;
114		} else {
115			command = 0;
116		}
117		break;
118
119	case I2C_SMBUS_BYTE_DATA:
120		protocol = ACPI_SMBUS_PRTCL_BYTE_DATA;
121		if (read_write == I2C_SMBUS_WRITE) {
122			mt_params[3].type = ACPI_TYPE_INTEGER;
123			mt_params[3].integer.value = 1;
124			mt_params[4].type = ACPI_TYPE_INTEGER;
125			mt_params[4].integer.value = data->byte;
126		}
127		break;
128
129	case I2C_SMBUS_WORD_DATA:
130		protocol = ACPI_SMBUS_PRTCL_WORD_DATA;
131		if (read_write == I2C_SMBUS_WRITE) {
132			mt_params[3].type = ACPI_TYPE_INTEGER;
133			mt_params[3].integer.value = 2;
134			mt_params[4].type = ACPI_TYPE_INTEGER;
135			mt_params[4].integer.value = data->word;
136		}
137		break;
138
139	case I2C_SMBUS_BLOCK_DATA:
140		protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA;
141		if (read_write == I2C_SMBUS_WRITE) {
142			len = data->block[0];
143			if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
144				return -EINVAL;
145			mt_params[3].type = ACPI_TYPE_INTEGER;
146			mt_params[3].integer.value = len;
147			mt_params[4].type = ACPI_TYPE_BUFFER;
148			mt_params[4].buffer.length = len;
149			mt_params[4].buffer.pointer = data->block + 1;
150		}
151		break;
152
153	default:
154		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
155		return -EOPNOTSUPP;
156	}
157
158	if (read_write == I2C_SMBUS_READ) {
159		protocol |= ACPI_SMBUS_PRTCL_READ;
160		method = smbus_cmi->methods->mt_sbr;
161		input.count = 3;
162	} else {
163		protocol |= ACPI_SMBUS_PRTCL_WRITE;
164		method = smbus_cmi->methods->mt_sbw;
165		input.count = 5;
166	}
167
168	input.pointer = mt_params;
169	mt_params[0].type = ACPI_TYPE_INTEGER;
170	mt_params[0].integer.value = protocol;
171	mt_params[1].type = ACPI_TYPE_INTEGER;
172	mt_params[1].integer.value = addr;
173	mt_params[2].type = ACPI_TYPE_INTEGER;
174	mt_params[2].integer.value = command;
175
176	status = acpi_evaluate_object(smbus_cmi->handle, method, &input,
177				      &buffer);
178	if (ACPI_FAILURE(status)) {
179		acpi_handle_err(smbus_cmi->handle,
180				"Failed to evaluate %s: %i\n", method, status);
181		return -EIO;
182	}
183
184	pkg = buffer.pointer;
185	if (pkg && pkg->type == ACPI_TYPE_PACKAGE)
186		obj = pkg->package.elements;
187	else {
188		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
189		result = -EIO;
190		goto out;
191	}
192	if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
193		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
194		result = -EIO;
195		goto out;
196	}
197
198	result = obj->integer.value;
199	acpi_handle_debug(smbus_cmi->handle,  "%s return status: %i\n", method,
200			  result);
201
202	switch (result) {
203	case ACPI_SMBUS_STATUS_OK:
204		result = 0;
205		break;
206	case ACPI_SMBUS_STATUS_BUSY:
207		result = -EBUSY;
208		goto out;
209	case ACPI_SMBUS_STATUS_TIMEOUT:
210		result = -ETIMEDOUT;
211		goto out;
212	case ACPI_SMBUS_STATUS_DNAK:
213		result = -ENXIO;
214		goto out;
215	default:
216		result = -EIO;
217		goto out;
218	}
219
220	if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK)
221		goto out;
222
223	obj = pkg->package.elements + 1;
224	if (obj->type != ACPI_TYPE_INTEGER) {
225		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
226		result = -EIO;
227		goto out;
228	}
229
230	len = obj->integer.value;
231	obj = pkg->package.elements + 2;
232	switch (size) {
233	case I2C_SMBUS_BYTE:
234	case I2C_SMBUS_BYTE_DATA:
235	case I2C_SMBUS_WORD_DATA:
236		if (obj->type != ACPI_TYPE_INTEGER) {
237			acpi_handle_err(smbus_cmi->handle,
238					"Invalid argument type\n");
239			result = -EIO;
240			goto out;
241		}
242		if (len == 2)
243			data->word = obj->integer.value;
244		else
245			data->byte = obj->integer.value;
246		break;
247	case I2C_SMBUS_BLOCK_DATA:
248		if (obj->type != ACPI_TYPE_BUFFER) {
249			acpi_handle_err(smbus_cmi->handle,
250					"Invalid argument type\n");
251			result = -EIO;
252			goto out;
253		}
254		if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
255			return -EPROTO;
256		data->block[0] = len;
257		memcpy(data->block + 1, obj->buffer.pointer, len);
258		break;
259	}
260
261out:
262	kfree(buffer.pointer);
263	dev_dbg(&adap->dev, "Transaction status: %i\n", result);
264	return result;
265}
266
267static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter)
268{
269	struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data;
270	u32 ret;
271
272	ret = smbus_cmi->cap_read | smbus_cmi->cap_write ?
273		I2C_FUNC_SMBUS_QUICK : 0;
274
275	ret |= smbus_cmi->cap_read ?
276		(I2C_FUNC_SMBUS_READ_BYTE |
277		I2C_FUNC_SMBUS_READ_BYTE_DATA |
278		I2C_FUNC_SMBUS_READ_WORD_DATA |
279		I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0;
280
281	ret |= smbus_cmi->cap_write ?
282		(I2C_FUNC_SMBUS_WRITE_BYTE |
283		I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
284		I2C_FUNC_SMBUS_WRITE_WORD_DATA |
285		I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0;
286
287	return ret;
288}
289
290static const struct i2c_algorithm acpi_smbus_cmi_algorithm = {
291	.smbus_xfer = acpi_smbus_cmi_access,
292	.functionality = acpi_smbus_cmi_func,
293};
294
295
296static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
297				  const char *name)
298{
299	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
300	struct acpi_handle *handle = smbus_cmi->handle;
301	union acpi_object *obj;
302	acpi_status status;
303
304	if (!strcmp(name, smbus_cmi->methods->mt_info)) {
305		status = acpi_evaluate_object(smbus_cmi->handle,
306					smbus_cmi->methods->mt_info,
307					NULL, &buffer);
308		if (ACPI_FAILURE(status)) {
309			acpi_handle_err(handle, "Failed to evaluate %s: %i\n",
310					smbus_cmi->methods->mt_info, status);
311			return -EIO;
312		}
313
314		obj = buffer.pointer;
315		if (obj && obj->type == ACPI_TYPE_PACKAGE)
316			obj = obj->package.elements;
317		else {
318			acpi_handle_err(handle, "Invalid argument type\n");
319			kfree(buffer.pointer);
320			return -EIO;
321		}
322
323		if (obj->type != ACPI_TYPE_INTEGER) {
324			acpi_handle_err(handle, "Invalid argument type\n");
325			kfree(buffer.pointer);
326			return -EIO;
327		} else
328			acpi_handle_debug(handle, "SMBus CMI Version %x\n",
329					  (int)obj->integer.value);
330
331		kfree(buffer.pointer);
332		smbus_cmi->cap_info = 1;
333	} else if (!strcmp(name, smbus_cmi->methods->mt_sbr))
334		smbus_cmi->cap_read = 1;
335	else if (!strcmp(name, smbus_cmi->methods->mt_sbw))
336		smbus_cmi->cap_write = 1;
337	else
338		acpi_handle_debug(handle, "Unsupported CMI method: %s\n", name);
339
340	return 0;
341}
342
343static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level,
344			void *context, void **return_value)
345{
346	char node_name[5];
347	struct acpi_buffer buffer = { sizeof(node_name), node_name };
348	struct acpi_smbus_cmi *smbus_cmi = context;
349	acpi_status status;
350
351	status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
352
353	if (ACPI_SUCCESS(status))
354		acpi_smbus_cmi_add_cap(smbus_cmi, node_name);
355
356	return AE_OK;
357}
358
359static int smbus_cmi_probe(struct platform_device *device)
360{
361	struct device *dev = &device->dev;
362	struct acpi_smbus_cmi *smbus_cmi;
363	int ret;
364
365	smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
366	if (!smbus_cmi)
367		return -ENOMEM;
368
369	smbus_cmi->handle = ACPI_HANDLE(dev);
370	smbus_cmi->methods = device_get_match_data(dev);
371
372	platform_set_drvdata(device, smbus_cmi);
373
374	smbus_cmi->cap_info = 0;
375	smbus_cmi->cap_read = 0;
376	smbus_cmi->cap_write = 0;
377
 
 
 
 
 
378	acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
379			    acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);
380
381	if (smbus_cmi->cap_info == 0) {
382		ret = -ENODEV;
383		goto err;
384	}
385
386	snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name),
387		 "SMBus CMI adapter %s", dev_name(dev));
 
388	smbus_cmi->adapter.owner = THIS_MODULE;
389	smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm;
390	smbus_cmi->adapter.algo_data = smbus_cmi;
391	smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
392	smbus_cmi->adapter.dev.parent = &device->dev;
393
394	ret = i2c_add_adapter(&smbus_cmi->adapter);
395	if (ret) {
396		dev_err(&device->dev, "Couldn't register adapter!\n");
397		goto err;
398	}
399
400	return 0;
401
402err:
403	kfree(smbus_cmi);
404	return ret;
 
405}
406
407static int smbus_cmi_remove(struct platform_device *device)
408{
409	struct acpi_smbus_cmi *smbus_cmi = platform_get_drvdata(device);
410
411	i2c_del_adapter(&smbus_cmi->adapter);
412	kfree(smbus_cmi);
 
413
414	return 0;
415}
416
417static struct platform_driver smbus_cmi_driver = {
418	.probe = smbus_cmi_probe,
419	.remove = smbus_cmi_remove,
420	.driver = {
421		.name   = "smbus_cmi",
422		.acpi_match_table = acpi_smbus_cmi_ids,
 
423	},
424};
425module_platform_driver(smbus_cmi_driver);
426
427MODULE_LICENSE("GPL");
428MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>");
429MODULE_DESCRIPTION("ACPI SMBus CMI driver");
v4.17
 
  1/*
  2 * SMBus driver for ACPI SMBus CMI
  3 *
  4 * Copyright (C) 2009 Crane Cai <crane.cai@amd.com>
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License as published by
  8 * the Free Software Foundation version 2.
  9 */
 10
 11#include <linux/module.h>
 
 12#include <linux/slab.h>
 13#include <linux/kernel.h>
 14#include <linux/stddef.h>
 15#include <linux/i2c.h>
 16#include <linux/acpi.h>
 17
 18#define ACPI_SMBUS_HC_CLASS		"smbus"
 19#define ACPI_SMBUS_HC_DEVICE_NAME	"cmi"
 20
 21/* SMBUS HID definition as supported by Microsoft Windows */
 22#define ACPI_SMBUS_MS_HID		"SMB0001"
 23
 24ACPI_MODULE_NAME("smbus_cmi");
 25
 26struct smbus_methods_t {
 27	char *mt_info;
 28	char *mt_sbr;
 29	char *mt_sbw;
 30};
 31
 32struct acpi_smbus_cmi {
 33	acpi_handle handle;
 34	struct i2c_adapter adapter;
 35	u8 cap_info:1;
 36	u8 cap_read:1;
 37	u8 cap_write:1;
 38	struct smbus_methods_t *methods;
 39};
 40
 41static const struct smbus_methods_t smbus_methods = {
 42	.mt_info = "_SBI",
 43	.mt_sbr  = "_SBR",
 44	.mt_sbw  = "_SBW",
 45};
 46
 47/* Some IBM BIOSes omit the leading underscore */
 48static const struct smbus_methods_t ibm_smbus_methods = {
 49	.mt_info = "SBI_",
 50	.mt_sbr  = "SBR_",
 51	.mt_sbw  = "SBW_",
 52};
 53
 54static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
 55	{"SMBUS01", (kernel_ulong_t)&smbus_methods},
 56	{ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods},
 57	{ACPI_SMBUS_MS_HID, (kernel_ulong_t)&smbus_methods},
 58	{"", 0}
 59};
 60MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids);
 61
 62#define ACPI_SMBUS_STATUS_OK			0x00
 63#define ACPI_SMBUS_STATUS_FAIL			0x07
 64#define ACPI_SMBUS_STATUS_DNAK			0x10
 65#define ACPI_SMBUS_STATUS_DERR			0x11
 66#define ACPI_SMBUS_STATUS_CMD_DENY		0x12
 67#define ACPI_SMBUS_STATUS_UNKNOWN		0x13
 68#define ACPI_SMBUS_STATUS_ACC_DENY		0x17
 69#define ACPI_SMBUS_STATUS_TIMEOUT		0x18
 70#define ACPI_SMBUS_STATUS_NOTSUP		0x19
 71#define ACPI_SMBUS_STATUS_BUSY			0x1a
 72#define ACPI_SMBUS_STATUS_PEC			0x1f
 73
 74#define ACPI_SMBUS_PRTCL_WRITE			0x00
 75#define ACPI_SMBUS_PRTCL_READ			0x01
 76#define ACPI_SMBUS_PRTCL_QUICK			0x02
 77#define ACPI_SMBUS_PRTCL_BYTE			0x04
 78#define ACPI_SMBUS_PRTCL_BYTE_DATA		0x06
 79#define ACPI_SMBUS_PRTCL_WORD_DATA		0x08
 80#define ACPI_SMBUS_PRTCL_BLOCK_DATA		0x0a
 81
 82
 83static int
 84acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
 85		   char read_write, u8 command, int size,
 86		   union i2c_smbus_data *data)
 87{
 88	int result = 0;
 89	struct acpi_smbus_cmi *smbus_cmi = adap->algo_data;
 90	unsigned char protocol;
 91	acpi_status status = 0;
 92	struct acpi_object_list input;
 93	union acpi_object mt_params[5];
 94	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 95	union acpi_object *obj;
 96	union acpi_object *pkg;
 97	char *method;
 98	int len = 0;
 99
100	dev_dbg(&adap->dev, "access size: %d %s\n", size,
101		(read_write) ? "READ" : "WRITE");
102	switch (size) {
103	case I2C_SMBUS_QUICK:
104		protocol = ACPI_SMBUS_PRTCL_QUICK;
105		command = 0;
106		if (read_write == I2C_SMBUS_WRITE) {
107			mt_params[3].type = ACPI_TYPE_INTEGER;
108			mt_params[3].integer.value = 0;
109			mt_params[4].type = ACPI_TYPE_INTEGER;
110			mt_params[4].integer.value = 0;
111		}
112		break;
113
114	case I2C_SMBUS_BYTE:
115		protocol = ACPI_SMBUS_PRTCL_BYTE;
116		if (read_write == I2C_SMBUS_WRITE) {
117			mt_params[3].type = ACPI_TYPE_INTEGER;
118			mt_params[3].integer.value = 0;
119			mt_params[4].type = ACPI_TYPE_INTEGER;
120			mt_params[4].integer.value = 0;
121		} else {
122			command = 0;
123		}
124		break;
125
126	case I2C_SMBUS_BYTE_DATA:
127		protocol = ACPI_SMBUS_PRTCL_BYTE_DATA;
128		if (read_write == I2C_SMBUS_WRITE) {
129			mt_params[3].type = ACPI_TYPE_INTEGER;
130			mt_params[3].integer.value = 1;
131			mt_params[4].type = ACPI_TYPE_INTEGER;
132			mt_params[4].integer.value = data->byte;
133		}
134		break;
135
136	case I2C_SMBUS_WORD_DATA:
137		protocol = ACPI_SMBUS_PRTCL_WORD_DATA;
138		if (read_write == I2C_SMBUS_WRITE) {
139			mt_params[3].type = ACPI_TYPE_INTEGER;
140			mt_params[3].integer.value = 2;
141			mt_params[4].type = ACPI_TYPE_INTEGER;
142			mt_params[4].integer.value = data->word;
143		}
144		break;
145
146	case I2C_SMBUS_BLOCK_DATA:
147		protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA;
148		if (read_write == I2C_SMBUS_WRITE) {
149			len = data->block[0];
150			if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
151				return -EINVAL;
152			mt_params[3].type = ACPI_TYPE_INTEGER;
153			mt_params[3].integer.value = len;
154			mt_params[4].type = ACPI_TYPE_BUFFER;
 
155			mt_params[4].buffer.pointer = data->block + 1;
156		}
157		break;
158
159	default:
160		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
161		return -EOPNOTSUPP;
162	}
163
164	if (read_write == I2C_SMBUS_READ) {
165		protocol |= ACPI_SMBUS_PRTCL_READ;
166		method = smbus_cmi->methods->mt_sbr;
167		input.count = 3;
168	} else {
169		protocol |= ACPI_SMBUS_PRTCL_WRITE;
170		method = smbus_cmi->methods->mt_sbw;
171		input.count = 5;
172	}
173
174	input.pointer = mt_params;
175	mt_params[0].type = ACPI_TYPE_INTEGER;
176	mt_params[0].integer.value = protocol;
177	mt_params[1].type = ACPI_TYPE_INTEGER;
178	mt_params[1].integer.value = addr;
179	mt_params[2].type = ACPI_TYPE_INTEGER;
180	mt_params[2].integer.value = command;
181
182	status = acpi_evaluate_object(smbus_cmi->handle, method, &input,
183				      &buffer);
184	if (ACPI_FAILURE(status)) {
185		acpi_handle_err(smbus_cmi->handle,
186				"Failed to evaluate %s: %i\n", method, status);
187		return -EIO;
188	}
189
190	pkg = buffer.pointer;
191	if (pkg && pkg->type == ACPI_TYPE_PACKAGE)
192		obj = pkg->package.elements;
193	else {
194		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
195		result = -EIO;
196		goto out;
197	}
198	if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
199		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
200		result = -EIO;
201		goto out;
202	}
203
204	result = obj->integer.value;
205	acpi_handle_debug(smbus_cmi->handle,  "%s return status: %i\n", method,
206			  result);
207
208	switch (result) {
209	case ACPI_SMBUS_STATUS_OK:
210		result = 0;
211		break;
212	case ACPI_SMBUS_STATUS_BUSY:
213		result = -EBUSY;
214		goto out;
215	case ACPI_SMBUS_STATUS_TIMEOUT:
216		result = -ETIMEDOUT;
217		goto out;
218	case ACPI_SMBUS_STATUS_DNAK:
219		result = -ENXIO;
220		goto out;
221	default:
222		result = -EIO;
223		goto out;
224	}
225
226	if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK)
227		goto out;
228
229	obj = pkg->package.elements + 1;
230	if (obj->type != ACPI_TYPE_INTEGER) {
231		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
232		result = -EIO;
233		goto out;
234	}
235
236	len = obj->integer.value;
237	obj = pkg->package.elements + 2;
238	switch (size) {
239	case I2C_SMBUS_BYTE:
240	case I2C_SMBUS_BYTE_DATA:
241	case I2C_SMBUS_WORD_DATA:
242		if (obj->type != ACPI_TYPE_INTEGER) {
243			acpi_handle_err(smbus_cmi->handle,
244					"Invalid argument type\n");
245			result = -EIO;
246			goto out;
247		}
248		if (len == 2)
249			data->word = obj->integer.value;
250		else
251			data->byte = obj->integer.value;
252		break;
253	case I2C_SMBUS_BLOCK_DATA:
254		if (obj->type != ACPI_TYPE_BUFFER) {
255			acpi_handle_err(smbus_cmi->handle,
256					"Invalid argument type\n");
257			result = -EIO;
258			goto out;
259		}
260		if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
261			return -EPROTO;
262		data->block[0] = len;
263		memcpy(data->block + 1, obj->buffer.pointer, len);
264		break;
265	}
266
267out:
268	kfree(buffer.pointer);
269	dev_dbg(&adap->dev, "Transaction status: %i\n", result);
270	return result;
271}
272
273static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter)
274{
275	struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data;
276	u32 ret;
277
278	ret = smbus_cmi->cap_read | smbus_cmi->cap_write ?
279		I2C_FUNC_SMBUS_QUICK : 0;
280
281	ret |= smbus_cmi->cap_read ?
282		(I2C_FUNC_SMBUS_READ_BYTE |
283		I2C_FUNC_SMBUS_READ_BYTE_DATA |
284		I2C_FUNC_SMBUS_READ_WORD_DATA |
285		I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0;
286
287	ret |= smbus_cmi->cap_write ?
288		(I2C_FUNC_SMBUS_WRITE_BYTE |
289		I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
290		I2C_FUNC_SMBUS_WRITE_WORD_DATA |
291		I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0;
292
293	return ret;
294}
295
296static const struct i2c_algorithm acpi_smbus_cmi_algorithm = {
297	.smbus_xfer = acpi_smbus_cmi_access,
298	.functionality = acpi_smbus_cmi_func,
299};
300
301
302static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
303				  const char *name)
304{
305	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
306	struct acpi_handle *handle = smbus_cmi->handle;
307	union acpi_object *obj;
308	acpi_status status;
309
310	if (!strcmp(name, smbus_cmi->methods->mt_info)) {
311		status = acpi_evaluate_object(smbus_cmi->handle,
312					smbus_cmi->methods->mt_info,
313					NULL, &buffer);
314		if (ACPI_FAILURE(status)) {
315			acpi_handle_err(handle, "Failed to evaluate %s: %i\n",
316					smbus_cmi->methods->mt_info, status);
317			return -EIO;
318		}
319
320		obj = buffer.pointer;
321		if (obj && obj->type == ACPI_TYPE_PACKAGE)
322			obj = obj->package.elements;
323		else {
324			acpi_handle_err(handle, "Invalid argument type\n");
325			kfree(buffer.pointer);
326			return -EIO;
327		}
328
329		if (obj->type != ACPI_TYPE_INTEGER) {
330			acpi_handle_err(handle, "Invalid argument type\n");
331			kfree(buffer.pointer);
332			return -EIO;
333		} else
334			acpi_handle_debug(handle, "SMBus CMI Version %x\n",
335					  (int)obj->integer.value);
336
337		kfree(buffer.pointer);
338		smbus_cmi->cap_info = 1;
339	} else if (!strcmp(name, smbus_cmi->methods->mt_sbr))
340		smbus_cmi->cap_read = 1;
341	else if (!strcmp(name, smbus_cmi->methods->mt_sbw))
342		smbus_cmi->cap_write = 1;
343	else
344		acpi_handle_debug(handle, "Unsupported CMI method: %s\n", name);
345
346	return 0;
347}
348
349static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level,
350			void *context, void **return_value)
351{
352	char node_name[5];
353	struct acpi_buffer buffer = { sizeof(node_name), node_name };
354	struct acpi_smbus_cmi *smbus_cmi = context;
355	acpi_status status;
356
357	status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
358
359	if (ACPI_SUCCESS(status))
360		acpi_smbus_cmi_add_cap(smbus_cmi, node_name);
361
362	return AE_OK;
363}
364
365static int acpi_smbus_cmi_add(struct acpi_device *device)
366{
 
367	struct acpi_smbus_cmi *smbus_cmi;
368	const struct acpi_device_id *id;
369
370	smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
371	if (!smbus_cmi)
372		return -ENOMEM;
373
374	smbus_cmi->handle = device->handle;
375	strcpy(acpi_device_name(device), ACPI_SMBUS_HC_DEVICE_NAME);
376	strcpy(acpi_device_class(device), ACPI_SMBUS_HC_CLASS);
377	device->driver_data = smbus_cmi;
 
378	smbus_cmi->cap_info = 0;
379	smbus_cmi->cap_read = 0;
380	smbus_cmi->cap_write = 0;
381
382	for (id = acpi_smbus_cmi_ids; id->id[0]; id++)
383		if (!strcmp(id->id, acpi_device_hid(device)))
384			smbus_cmi->methods =
385				(struct smbus_methods_t *) id->driver_data;
386
387	acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
388			    acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);
389
390	if (smbus_cmi->cap_info == 0)
 
391		goto err;
 
392
393	snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name),
394		"SMBus CMI adapter %s",
395		acpi_device_name(device));
396	smbus_cmi->adapter.owner = THIS_MODULE;
397	smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm;
398	smbus_cmi->adapter.algo_data = smbus_cmi;
399	smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
400	smbus_cmi->adapter.dev.parent = &device->dev;
401
402	if (i2c_add_adapter(&smbus_cmi->adapter)) {
 
403		dev_err(&device->dev, "Couldn't register adapter!\n");
404		goto err;
405	}
406
407	return 0;
408
409err:
410	kfree(smbus_cmi);
411	device->driver_data = NULL;
412	return -EIO;
413}
414
415static int acpi_smbus_cmi_remove(struct acpi_device *device)
416{
417	struct acpi_smbus_cmi *smbus_cmi = acpi_driver_data(device);
418
419	i2c_del_adapter(&smbus_cmi->adapter);
420	kfree(smbus_cmi);
421	device->driver_data = NULL;
422
423	return 0;
424}
425
426static struct acpi_driver acpi_smbus_cmi_driver = {
427	.name = ACPI_SMBUS_HC_DEVICE_NAME,
428	.class = ACPI_SMBUS_HC_CLASS,
429	.ids = acpi_smbus_cmi_ids,
430	.ops = {
431		.add = acpi_smbus_cmi_add,
432		.remove = acpi_smbus_cmi_remove,
433	},
434};
435module_acpi_driver(acpi_smbus_cmi_driver);
436
437MODULE_LICENSE("GPL");
438MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>");
439MODULE_DESCRIPTION("ACPI SMBus CMI driver");