2 * SMBus driver for ACPI SMBus CMI
4 * Copyright (C) 2009 Crane Cai <crane.cai@amd.com>
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.
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/kernel.h>
14 #include <linux/stddef.h>
15 #include <linux/init.h>
16 #include <linux/i2c.h>
17 #include <linux/acpi.h>
19 #define ACPI_SMBUS_HC_CLASS "smbus"
20 #define ACPI_SMBUS_HC_DEVICE_NAME "cmi"
22 ACPI_MODULE_NAME("smbus_cmi");
24 struct smbus_methods_t {
30 struct acpi_smbus_cmi {
32 struct i2c_adapter adapter;
38 static const struct smbus_methods_t smbus_methods = {
44 static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
49 #define ACPI_SMBUS_STATUS_OK 0x00
50 #define ACPI_SMBUS_STATUS_FAIL 0x07
51 #define ACPI_SMBUS_STATUS_DNAK 0x10
52 #define ACPI_SMBUS_STATUS_DERR 0x11
53 #define ACPI_SMBUS_STATUS_CMD_DENY 0x12
54 #define ACPI_SMBUS_STATUS_UNKNOWN 0x13
55 #define ACPI_SMBUS_STATUS_ACC_DENY 0x17
56 #define ACPI_SMBUS_STATUS_TIMEOUT 0x18
57 #define ACPI_SMBUS_STATUS_NOTSUP 0x19
58 #define ACPI_SMBUS_STATUS_BUSY 0x1a
59 #define ACPI_SMBUS_STATUS_PEC 0x1f
61 #define ACPI_SMBUS_PRTCL_WRITE 0x00
62 #define ACPI_SMBUS_PRTCL_READ 0x01
63 #define ACPI_SMBUS_PRTCL_QUICK 0x02
64 #define ACPI_SMBUS_PRTCL_BYTE 0x04
65 #define ACPI_SMBUS_PRTCL_BYTE_DATA 0x06
66 #define ACPI_SMBUS_PRTCL_WORD_DATA 0x08
67 #define ACPI_SMBUS_PRTCL_BLOCK_DATA 0x0a
71 acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
72 char read_write, u8 command, int size,
73 union i2c_smbus_data *data)
76 struct acpi_smbus_cmi *smbus_cmi = adap->algo_data;
77 unsigned char protocol;
78 acpi_status status = 0;
79 struct acpi_object_list input;
80 union acpi_object mt_params[5];
81 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
82 union acpi_object *obj;
83 union acpi_object *pkg;
87 dev_dbg(&adap->dev, "access size: %d %s\n", size,
88 (read_write) ? "READ" : "WRITE");
91 protocol = ACPI_SMBUS_PRTCL_QUICK;
93 if (read_write == I2C_SMBUS_WRITE) {
94 mt_params[3].type = ACPI_TYPE_INTEGER;
95 mt_params[3].integer.value = 0;
96 mt_params[4].type = ACPI_TYPE_INTEGER;
97 mt_params[4].integer.value = 0;
102 protocol = ACPI_SMBUS_PRTCL_BYTE;
103 if (read_write == I2C_SMBUS_WRITE) {
104 mt_params[3].type = ACPI_TYPE_INTEGER;
105 mt_params[3].integer.value = 0;
106 mt_params[4].type = ACPI_TYPE_INTEGER;
107 mt_params[4].integer.value = 0;
113 case I2C_SMBUS_BYTE_DATA:
114 protocol = ACPI_SMBUS_PRTCL_BYTE_DATA;
115 if (read_write == I2C_SMBUS_WRITE) {
116 mt_params[3].type = ACPI_TYPE_INTEGER;
117 mt_params[3].integer.value = 1;
118 mt_params[4].type = ACPI_TYPE_INTEGER;
119 mt_params[4].integer.value = data->byte;
123 case I2C_SMBUS_WORD_DATA:
124 protocol = ACPI_SMBUS_PRTCL_WORD_DATA;
125 if (read_write == I2C_SMBUS_WRITE) {
126 mt_params[3].type = ACPI_TYPE_INTEGER;
127 mt_params[3].integer.value = 2;
128 mt_params[4].type = ACPI_TYPE_INTEGER;
129 mt_params[4].integer.value = data->word;
133 case I2C_SMBUS_BLOCK_DATA:
134 protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA;
135 if (read_write == I2C_SMBUS_WRITE) {
136 len = data->block[0];
137 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
139 mt_params[3].type = ACPI_TYPE_INTEGER;
140 mt_params[3].integer.value = len;
141 mt_params[4].type = ACPI_TYPE_BUFFER;
142 mt_params[4].buffer.pointer = data->block + 1;
147 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
151 if (read_write == I2C_SMBUS_READ) {
152 protocol |= ACPI_SMBUS_PRTCL_READ;
153 method = smbus_methods.mt_sbr;
156 protocol |= ACPI_SMBUS_PRTCL_WRITE;
157 method = smbus_methods.mt_sbw;
161 input.pointer = mt_params;
162 mt_params[0].type = ACPI_TYPE_INTEGER;
163 mt_params[0].integer.value = protocol;
164 mt_params[1].type = ACPI_TYPE_INTEGER;
165 mt_params[1].integer.value = addr;
166 mt_params[2].type = ACPI_TYPE_INTEGER;
167 mt_params[2].integer.value = command;
169 status = acpi_evaluate_object(smbus_cmi->handle, method, &input,
171 if (ACPI_FAILURE(status)) {
172 ACPI_ERROR((AE_INFO, "Evaluating %s: %i", method, status));
176 pkg = buffer.pointer;
177 if (pkg && pkg->type == ACPI_TYPE_PACKAGE)
178 obj = pkg->package.elements;
180 ACPI_ERROR((AE_INFO, "Invalid argument type"));
184 if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
185 ACPI_ERROR((AE_INFO, "Invalid argument type"));
190 result = obj->integer.value;
191 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s return status: %i\n",
195 case ACPI_SMBUS_STATUS_OK:
198 case ACPI_SMBUS_STATUS_BUSY:
201 case ACPI_SMBUS_STATUS_TIMEOUT:
204 case ACPI_SMBUS_STATUS_DNAK:
212 if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK)
215 obj = pkg->package.elements + 1;
216 if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
217 ACPI_ERROR((AE_INFO, "Invalid argument type"));
222 len = obj->integer.value;
223 obj = pkg->package.elements + 2;
226 case I2C_SMBUS_BYTE_DATA:
227 case I2C_SMBUS_WORD_DATA:
228 if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
229 ACPI_ERROR((AE_INFO, "Invalid argument type"));
234 data->word = obj->integer.value;
236 data->byte = obj->integer.value;
238 case I2C_SMBUS_BLOCK_DATA:
239 if (obj == NULL || obj->type != ACPI_TYPE_BUFFER) {
240 ACPI_ERROR((AE_INFO, "Invalid argument type"));
244 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
246 data->block[0] = len;
247 memcpy(data->block + 1, obj->buffer.pointer, len);
252 kfree(buffer.pointer);
253 dev_dbg(&adap->dev, "Transaction status: %i\n", result);
257 static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter)
259 struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data;
262 ret = smbus_cmi->cap_read | smbus_cmi->cap_write ?
263 I2C_FUNC_SMBUS_QUICK : 0;
265 ret |= smbus_cmi->cap_read ?
266 (I2C_FUNC_SMBUS_READ_BYTE |
267 I2C_FUNC_SMBUS_READ_BYTE_DATA |
268 I2C_FUNC_SMBUS_READ_WORD_DATA |
269 I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0;
271 ret |= smbus_cmi->cap_write ?
272 (I2C_FUNC_SMBUS_WRITE_BYTE |
273 I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
274 I2C_FUNC_SMBUS_WRITE_WORD_DATA |
275 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0;
280 static const struct i2c_algorithm acpi_smbus_cmi_algorithm = {
281 .smbus_xfer = acpi_smbus_cmi_access,
282 .functionality = acpi_smbus_cmi_func,
286 static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
289 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
290 union acpi_object *obj;
293 if (!strcmp(name, smbus_methods.mt_info)) {
294 status = acpi_evaluate_object(smbus_cmi->handle,
295 smbus_methods.mt_info,
297 if (ACPI_FAILURE(status)) {
298 ACPI_ERROR((AE_INFO, "Evaluating %s: %i",
299 smbus_methods.mt_info, status));
303 obj = buffer.pointer;
304 if (obj && obj->type == ACPI_TYPE_PACKAGE)
305 obj = obj->package.elements;
307 ACPI_ERROR((AE_INFO, "Invalid argument type"));
308 kfree(buffer.pointer);
312 if (obj->type != ACPI_TYPE_INTEGER) {
313 ACPI_ERROR((AE_INFO, "Invalid argument type"));
314 kfree(buffer.pointer);
317 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "SMBus CMI Version %x"
318 "\n", (int)obj->integer.value));
320 kfree(buffer.pointer);
321 smbus_cmi->cap_info = 1;
322 } else if (!strcmp(name, smbus_methods.mt_sbr))
323 smbus_cmi->cap_read = 1;
324 else if (!strcmp(name, smbus_methods.mt_sbw))
325 smbus_cmi->cap_write = 1;
327 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Unsupported CMI method: %s\n",
333 static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level,
334 void *context, void **return_value)
337 struct acpi_buffer buffer = { sizeof(node_name), node_name };
338 struct acpi_smbus_cmi *smbus_cmi = context;
341 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
343 if (ACPI_SUCCESS(status))
344 acpi_smbus_cmi_add_cap(smbus_cmi, node_name);
349 static int acpi_smbus_cmi_add(struct acpi_device *device)
351 struct acpi_smbus_cmi *smbus_cmi;
353 smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
357 smbus_cmi->handle = device->handle;
358 strcpy(acpi_device_name(device), ACPI_SMBUS_HC_DEVICE_NAME);
359 strcpy(acpi_device_class(device), ACPI_SMBUS_HC_CLASS);
360 device->driver_data = smbus_cmi;
361 smbus_cmi->cap_info = 0;
362 smbus_cmi->cap_read = 0;
363 smbus_cmi->cap_write = 0;
365 acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
366 acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);
368 if (smbus_cmi->cap_info == 0)
371 snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name),
372 "SMBus CMI adapter %s",
373 acpi_device_name(device));
374 smbus_cmi->adapter.owner = THIS_MODULE;
375 smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm;
376 smbus_cmi->adapter.algo_data = smbus_cmi;
377 smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
378 smbus_cmi->adapter.dev.parent = &device->dev;
380 if (i2c_add_adapter(&smbus_cmi->adapter)) {
381 dev_err(&device->dev, "Couldn't register adapter!\n");
389 device->driver_data = NULL;
393 static int acpi_smbus_cmi_remove(struct acpi_device *device, int type)
395 struct acpi_smbus_cmi *smbus_cmi = acpi_driver_data(device);
397 i2c_del_adapter(&smbus_cmi->adapter);
399 device->driver_data = NULL;
404 static struct acpi_driver acpi_smbus_cmi_driver = {
405 .name = ACPI_SMBUS_HC_DEVICE_NAME,
406 .class = ACPI_SMBUS_HC_CLASS,
407 .ids = acpi_smbus_cmi_ids,
409 .add = acpi_smbus_cmi_add,
410 .remove = acpi_smbus_cmi_remove,
414 static int __init acpi_smbus_cmi_init(void)
416 return acpi_bus_register_driver(&acpi_smbus_cmi_driver);
419 static void __exit acpi_smbus_cmi_exit(void)
421 acpi_bus_unregister_driver(&acpi_smbus_cmi_driver);
424 module_init(acpi_smbus_cmi_init);
425 module_exit(acpi_smbus_cmi_exit);
427 MODULE_LICENSE("GPL");
428 MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>");
429 MODULE_DESCRIPTION("ACPI SMBus CMI driver");