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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");
v5.14.15
  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/slab.h>
 10#include <linux/kernel.h>
 11#include <linux/stddef.h>
 12#include <linux/i2c.h>
 13#include <linux/acpi.h>
 14
 15#define ACPI_SMBUS_HC_CLASS		"smbus"
 16#define ACPI_SMBUS_HC_DEVICE_NAME	"cmi"
 17
 18/* SMBUS HID definition as supported by Microsoft Windows */
 19#define ACPI_SMBUS_MS_HID		"SMB0001"
 20
 21struct smbus_methods_t {
 22	char *mt_info;
 23	char *mt_sbr;
 24	char *mt_sbw;
 25};
 26
 27struct acpi_smbus_cmi {
 28	acpi_handle handle;
 29	struct i2c_adapter adapter;
 30	u8 cap_info:1;
 31	u8 cap_read:1;
 32	u8 cap_write:1;
 33	struct smbus_methods_t *methods;
 34};
 35
 36static const struct smbus_methods_t smbus_methods = {
 37	.mt_info = "_SBI",
 38	.mt_sbr  = "_SBR",
 39	.mt_sbw  = "_SBW",
 40};
 41
 42/* Some IBM BIOSes omit the leading underscore */
 43static const struct smbus_methods_t ibm_smbus_methods = {
 44	.mt_info = "SBI_",
 45	.mt_sbr  = "SBR_",
 46	.mt_sbw  = "SBW_",
 47};
 48
 49static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
 50	{"SMBUS01", (kernel_ulong_t)&smbus_methods},
 51	{ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods},
 52	{ACPI_SMBUS_MS_HID, (kernel_ulong_t)&smbus_methods},
 53	{"", 0}
 54};
 55MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids);
 56
 57#define ACPI_SMBUS_STATUS_OK			0x00
 58#define ACPI_SMBUS_STATUS_FAIL			0x07
 59#define ACPI_SMBUS_STATUS_DNAK			0x10
 60#define ACPI_SMBUS_STATUS_DERR			0x11
 61#define ACPI_SMBUS_STATUS_CMD_DENY		0x12
 62#define ACPI_SMBUS_STATUS_UNKNOWN		0x13
 63#define ACPI_SMBUS_STATUS_ACC_DENY		0x17
 64#define ACPI_SMBUS_STATUS_TIMEOUT		0x18
 65#define ACPI_SMBUS_STATUS_NOTSUP		0x19
 66#define ACPI_SMBUS_STATUS_BUSY			0x1a
 67#define ACPI_SMBUS_STATUS_PEC			0x1f
 68
 69#define ACPI_SMBUS_PRTCL_WRITE			0x00
 70#define ACPI_SMBUS_PRTCL_READ			0x01
 71#define ACPI_SMBUS_PRTCL_QUICK			0x02
 72#define ACPI_SMBUS_PRTCL_BYTE			0x04
 73#define ACPI_SMBUS_PRTCL_BYTE_DATA		0x06
 74#define ACPI_SMBUS_PRTCL_WORD_DATA		0x08
 75#define ACPI_SMBUS_PRTCL_BLOCK_DATA		0x0a
 76
 77
 78static int
 79acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
 80		   char read_write, u8 command, int size,
 81		   union i2c_smbus_data *data)
 82{
 83	int result = 0;
 84	struct acpi_smbus_cmi *smbus_cmi = adap->algo_data;
 85	unsigned char protocol;
 86	acpi_status status = 0;
 87	struct acpi_object_list input;
 88	union acpi_object mt_params[5];
 89	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 90	union acpi_object *obj;
 91	union acpi_object *pkg;
 92	char *method;
 93	int len = 0;
 94
 95	dev_dbg(&adap->dev, "access size: %d %s\n", size,
 96		(read_write) ? "READ" : "WRITE");
 97	switch (size) {
 98	case I2C_SMBUS_QUICK:
 99		protocol = ACPI_SMBUS_PRTCL_QUICK;
100		command = 0;
101		if (read_write == I2C_SMBUS_WRITE) {
102			mt_params[3].type = ACPI_TYPE_INTEGER;
103			mt_params[3].integer.value = 0;
104			mt_params[4].type = ACPI_TYPE_INTEGER;
105			mt_params[4].integer.value = 0;
106		}
107		break;
108
109	case I2C_SMBUS_BYTE:
110		protocol = ACPI_SMBUS_PRTCL_BYTE;
111		if (read_write == I2C_SMBUS_WRITE) {
112			mt_params[3].type = ACPI_TYPE_INTEGER;
113			mt_params[3].integer.value = 0;
114			mt_params[4].type = ACPI_TYPE_INTEGER;
115			mt_params[4].integer.value = 0;
116		} else {
117			command = 0;
118		}
119		break;
120
121	case I2C_SMBUS_BYTE_DATA:
122		protocol = ACPI_SMBUS_PRTCL_BYTE_DATA;
123		if (read_write == I2C_SMBUS_WRITE) {
124			mt_params[3].type = ACPI_TYPE_INTEGER;
125			mt_params[3].integer.value = 1;
126			mt_params[4].type = ACPI_TYPE_INTEGER;
127			mt_params[4].integer.value = data->byte;
128		}
129		break;
130
131	case I2C_SMBUS_WORD_DATA:
132		protocol = ACPI_SMBUS_PRTCL_WORD_DATA;
133		if (read_write == I2C_SMBUS_WRITE) {
134			mt_params[3].type = ACPI_TYPE_INTEGER;
135			mt_params[3].integer.value = 2;
136			mt_params[4].type = ACPI_TYPE_INTEGER;
137			mt_params[4].integer.value = data->word;
138		}
139		break;
140
141	case I2C_SMBUS_BLOCK_DATA:
142		protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA;
143		if (read_write == I2C_SMBUS_WRITE) {
144			len = data->block[0];
145			if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
146				return -EINVAL;
147			mt_params[3].type = ACPI_TYPE_INTEGER;
148			mt_params[3].integer.value = len;
149			mt_params[4].type = ACPI_TYPE_BUFFER;
150			mt_params[4].buffer.length = len;
151			mt_params[4].buffer.pointer = data->block + 1;
152		}
153		break;
154
155	default:
156		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
157		return -EOPNOTSUPP;
158	}
159
160	if (read_write == I2C_SMBUS_READ) {
161		protocol |= ACPI_SMBUS_PRTCL_READ;
162		method = smbus_cmi->methods->mt_sbr;
163		input.count = 3;
164	} else {
165		protocol |= ACPI_SMBUS_PRTCL_WRITE;
166		method = smbus_cmi->methods->mt_sbw;
167		input.count = 5;
168	}
169
170	input.pointer = mt_params;
171	mt_params[0].type = ACPI_TYPE_INTEGER;
172	mt_params[0].integer.value = protocol;
173	mt_params[1].type = ACPI_TYPE_INTEGER;
174	mt_params[1].integer.value = addr;
175	mt_params[2].type = ACPI_TYPE_INTEGER;
176	mt_params[2].integer.value = command;
177
178	status = acpi_evaluate_object(smbus_cmi->handle, method, &input,
179				      &buffer);
180	if (ACPI_FAILURE(status)) {
181		acpi_handle_err(smbus_cmi->handle,
182				"Failed to evaluate %s: %i\n", method, status);
183		return -EIO;
184	}
185
186	pkg = buffer.pointer;
187	if (pkg && pkg->type == ACPI_TYPE_PACKAGE)
188		obj = pkg->package.elements;
189	else {
190		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
191		result = -EIO;
192		goto out;
193	}
194	if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
195		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
196		result = -EIO;
197		goto out;
198	}
199
200	result = obj->integer.value;
201	acpi_handle_debug(smbus_cmi->handle,  "%s return status: %i\n", method,
202			  result);
203
204	switch (result) {
205	case ACPI_SMBUS_STATUS_OK:
206		result = 0;
207		break;
208	case ACPI_SMBUS_STATUS_BUSY:
209		result = -EBUSY;
210		goto out;
211	case ACPI_SMBUS_STATUS_TIMEOUT:
212		result = -ETIMEDOUT;
213		goto out;
214	case ACPI_SMBUS_STATUS_DNAK:
215		result = -ENXIO;
216		goto out;
217	default:
218		result = -EIO;
219		goto out;
220	}
221
222	if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK)
223		goto out;
224
225	obj = pkg->package.elements + 1;
226	if (obj->type != ACPI_TYPE_INTEGER) {
227		acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
228		result = -EIO;
229		goto out;
230	}
231
232	len = obj->integer.value;
233	obj = pkg->package.elements + 2;
234	switch (size) {
235	case I2C_SMBUS_BYTE:
236	case I2C_SMBUS_BYTE_DATA:
237	case I2C_SMBUS_WORD_DATA:
238		if (obj->type != ACPI_TYPE_INTEGER) {
239			acpi_handle_err(smbus_cmi->handle,
240					"Invalid argument type\n");
241			result = -EIO;
242			goto out;
243		}
244		if (len == 2)
245			data->word = obj->integer.value;
246		else
247			data->byte = obj->integer.value;
248		break;
249	case I2C_SMBUS_BLOCK_DATA:
250		if (obj->type != ACPI_TYPE_BUFFER) {
251			acpi_handle_err(smbus_cmi->handle,
252					"Invalid argument type\n");
253			result = -EIO;
254			goto out;
255		}
256		if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
257			return -EPROTO;
258		data->block[0] = len;
259		memcpy(data->block + 1, obj->buffer.pointer, len);
260		break;
261	}
262
263out:
264	kfree(buffer.pointer);
265	dev_dbg(&adap->dev, "Transaction status: %i\n", result);
266	return result;
267}
268
269static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter)
270{
271	struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data;
272	u32 ret;
273
274	ret = smbus_cmi->cap_read | smbus_cmi->cap_write ?
275		I2C_FUNC_SMBUS_QUICK : 0;
276
277	ret |= smbus_cmi->cap_read ?
278		(I2C_FUNC_SMBUS_READ_BYTE |
279		I2C_FUNC_SMBUS_READ_BYTE_DATA |
280		I2C_FUNC_SMBUS_READ_WORD_DATA |
281		I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0;
282
283	ret |= smbus_cmi->cap_write ?
284		(I2C_FUNC_SMBUS_WRITE_BYTE |
285		I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
286		I2C_FUNC_SMBUS_WRITE_WORD_DATA |
287		I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0;
288
289	return ret;
290}
291
292static const struct i2c_algorithm acpi_smbus_cmi_algorithm = {
293	.smbus_xfer = acpi_smbus_cmi_access,
294	.functionality = acpi_smbus_cmi_func,
295};
296
297
298static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
299				  const char *name)
300{
301	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
302	struct acpi_handle *handle = smbus_cmi->handle;
303	union acpi_object *obj;
304	acpi_status status;
305
306	if (!strcmp(name, smbus_cmi->methods->mt_info)) {
307		status = acpi_evaluate_object(smbus_cmi->handle,
308					smbus_cmi->methods->mt_info,
309					NULL, &buffer);
310		if (ACPI_FAILURE(status)) {
311			acpi_handle_err(handle, "Failed to evaluate %s: %i\n",
312					smbus_cmi->methods->mt_info, status);
313			return -EIO;
314		}
315
316		obj = buffer.pointer;
317		if (obj && obj->type == ACPI_TYPE_PACKAGE)
318			obj = obj->package.elements;
319		else {
320			acpi_handle_err(handle, "Invalid argument type\n");
321			kfree(buffer.pointer);
322			return -EIO;
323		}
324
325		if (obj->type != ACPI_TYPE_INTEGER) {
326			acpi_handle_err(handle, "Invalid argument type\n");
327			kfree(buffer.pointer);
328			return -EIO;
329		} else
330			acpi_handle_debug(handle, "SMBus CMI Version %x\n",
331					  (int)obj->integer.value);
332
333		kfree(buffer.pointer);
334		smbus_cmi->cap_info = 1;
335	} else if (!strcmp(name, smbus_cmi->methods->mt_sbr))
336		smbus_cmi->cap_read = 1;
337	else if (!strcmp(name, smbus_cmi->methods->mt_sbw))
338		smbus_cmi->cap_write = 1;
339	else
340		acpi_handle_debug(handle, "Unsupported CMI method: %s\n", name);
341
342	return 0;
343}
344
345static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level,
346			void *context, void **return_value)
347{
348	char node_name[5];
349	struct acpi_buffer buffer = { sizeof(node_name), node_name };
350	struct acpi_smbus_cmi *smbus_cmi = context;
351	acpi_status status;
352
353	status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
354
355	if (ACPI_SUCCESS(status))
356		acpi_smbus_cmi_add_cap(smbus_cmi, node_name);
357
358	return AE_OK;
359}
360
361static int acpi_smbus_cmi_add(struct acpi_device *device)
362{
 
363	struct acpi_smbus_cmi *smbus_cmi;
364	const struct acpi_device_id *id;
365	int ret;
366
367	smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
368	if (!smbus_cmi)
369		return -ENOMEM;
370
371	smbus_cmi->handle = device->handle;
372	strcpy(acpi_device_name(device), ACPI_SMBUS_HC_DEVICE_NAME);
373	strcpy(acpi_device_class(device), ACPI_SMBUS_HC_CLASS);
374	device->driver_data = smbus_cmi;
 
375	smbus_cmi->cap_info = 0;
376	smbus_cmi->cap_read = 0;
377	smbus_cmi->cap_write = 0;
378
379	for (id = acpi_smbus_cmi_ids; id->id[0]; id++)
380		if (!strcmp(id->id, acpi_device_hid(device)))
381			smbus_cmi->methods =
382				(struct smbus_methods_t *) id->driver_data;
383
384	acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
385			    acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);
386
387	if (smbus_cmi->cap_info == 0) {
388		ret = -ENODEV;
389		goto err;
390	}
391
392	snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name),
393		"SMBus CMI adapter %s",
394		acpi_device_name(device));
395	smbus_cmi->adapter.owner = THIS_MODULE;
396	smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm;
397	smbus_cmi->adapter.algo_data = smbus_cmi;
398	smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
399	smbus_cmi->adapter.dev.parent = &device->dev;
400
401	ret = i2c_add_adapter(&smbus_cmi->adapter);
402	if (ret) {
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 ret;
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");