Crane Cai | dc98542 | 2009-09-18 22:45:51 +0200 | [diff] [blame] | 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/init.h> |
| 16 | #include <linux/i2c.h> |
| 17 | #include <linux/acpi.h> |
| 18 | |
| 19 | #define ACPI_SMBUS_HC_CLASS "smbus" |
| 20 | #define ACPI_SMBUS_HC_DEVICE_NAME "cmi" |
| 21 | |
| 22 | ACPI_MODULE_NAME("smbus_cmi"); |
| 23 | |
| 24 | struct smbus_methods_t { |
| 25 | char *mt_info; |
| 26 | char *mt_sbr; |
| 27 | char *mt_sbw; |
| 28 | }; |
| 29 | |
| 30 | struct acpi_smbus_cmi { |
| 31 | acpi_handle handle; |
| 32 | struct i2c_adapter adapter; |
| 33 | u8 cap_info:1; |
| 34 | u8 cap_read:1; |
| 35 | u8 cap_write:1; |
| 36 | }; |
| 37 | |
| 38 | static const struct smbus_methods_t smbus_methods = { |
| 39 | .mt_info = "_SBI", |
| 40 | .mt_sbr = "_SBR", |
| 41 | .mt_sbw = "_SBW", |
| 42 | }; |
| 43 | |
| 44 | static const struct acpi_device_id acpi_smbus_cmi_ids[] = { |
| 45 | {"SMBUS01", 0}, |
| 46 | {"", 0} |
| 47 | }; |
| 48 | |
| 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 |
| 60 | |
| 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 |
| 68 | |
| 69 | |
| 70 | static int |
| 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) |
| 74 | { |
| 75 | int result = 0; |
| 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; |
| 84 | char *method; |
| 85 | int len = 0; |
| 86 | |
| 87 | dev_dbg(&adap->dev, "access size: %d %s\n", size, |
| 88 | (read_write) ? "READ" : "WRITE"); |
| 89 | switch (size) { |
| 90 | case I2C_SMBUS_QUICK: |
| 91 | protocol = ACPI_SMBUS_PRTCL_QUICK; |
| 92 | command = 0; |
| 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; |
| 98 | } |
| 99 | break; |
| 100 | |
| 101 | case I2C_SMBUS_BYTE: |
| 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; |
| 108 | } else { |
| 109 | command = 0; |
| 110 | } |
| 111 | break; |
| 112 | |
| 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; |
| 120 | } |
| 121 | break; |
| 122 | |
| 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; |
| 130 | } |
| 131 | break; |
| 132 | |
| 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) |
| 138 | return -EINVAL; |
| 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; |
| 143 | } |
| 144 | break; |
| 145 | |
| 146 | default: |
| 147 | dev_warn(&adap->dev, "Unsupported transaction %d\n", size); |
| 148 | return -EOPNOTSUPP; |
| 149 | } |
| 150 | |
| 151 | if (read_write == I2C_SMBUS_READ) { |
| 152 | protocol |= ACPI_SMBUS_PRTCL_READ; |
| 153 | method = smbus_methods.mt_sbr; |
| 154 | input.count = 3; |
| 155 | } else { |
| 156 | protocol |= ACPI_SMBUS_PRTCL_WRITE; |
| 157 | method = smbus_methods.mt_sbw; |
| 158 | input.count = 5; |
| 159 | } |
| 160 | |
| 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; |
| 168 | |
| 169 | status = acpi_evaluate_object(smbus_cmi->handle, method, &input, |
| 170 | &buffer); |
| 171 | if (ACPI_FAILURE(status)) { |
| 172 | ACPI_ERROR((AE_INFO, "Evaluating %s: %i", method, status)); |
| 173 | return -EIO; |
| 174 | } |
| 175 | |
| 176 | pkg = buffer.pointer; |
| 177 | if (pkg && pkg->type == ACPI_TYPE_PACKAGE) |
| 178 | obj = pkg->package.elements; |
| 179 | else { |
| 180 | ACPI_ERROR((AE_INFO, "Invalid argument type")); |
| 181 | result = -EIO; |
| 182 | goto out; |
| 183 | } |
| 184 | if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) { |
| 185 | ACPI_ERROR((AE_INFO, "Invalid argument type")); |
| 186 | result = -EIO; |
| 187 | goto out; |
| 188 | } |
| 189 | |
| 190 | result = obj->integer.value; |
| 191 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s return status: %i\n", |
| 192 | method, result)); |
| 193 | |
| 194 | switch (result) { |
| 195 | case ACPI_SMBUS_STATUS_OK: |
| 196 | result = 0; |
| 197 | break; |
| 198 | case ACPI_SMBUS_STATUS_BUSY: |
| 199 | result = -EBUSY; |
| 200 | goto out; |
| 201 | case ACPI_SMBUS_STATUS_TIMEOUT: |
| 202 | result = -ETIMEDOUT; |
| 203 | goto out; |
| 204 | case ACPI_SMBUS_STATUS_DNAK: |
| 205 | result = -ENXIO; |
| 206 | goto out; |
| 207 | default: |
| 208 | result = -EIO; |
| 209 | goto out; |
| 210 | } |
| 211 | |
| 212 | if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK) |
| 213 | goto out; |
| 214 | |
| 215 | obj = pkg->package.elements + 1; |
| 216 | if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) { |
| 217 | ACPI_ERROR((AE_INFO, "Invalid argument type")); |
| 218 | result = -EIO; |
| 219 | goto out; |
| 220 | } |
| 221 | |
| 222 | len = obj->integer.value; |
| 223 | obj = pkg->package.elements + 2; |
| 224 | switch (size) { |
| 225 | case I2C_SMBUS_BYTE: |
| 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")); |
| 230 | result = -EIO; |
| 231 | goto out; |
| 232 | } |
| 233 | if (len == 2) |
| 234 | data->word = obj->integer.value; |
| 235 | else |
| 236 | data->byte = obj->integer.value; |
| 237 | break; |
| 238 | case I2C_SMBUS_BLOCK_DATA: |
| 239 | if (obj == NULL || obj->type != ACPI_TYPE_BUFFER) { |
| 240 | ACPI_ERROR((AE_INFO, "Invalid argument type")); |
| 241 | result = -EIO; |
| 242 | goto out; |
| 243 | } |
| 244 | if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) |
| 245 | return -EPROTO; |
| 246 | data->block[0] = len; |
| 247 | memcpy(data->block + 1, obj->buffer.pointer, len); |
| 248 | break; |
| 249 | } |
| 250 | |
| 251 | out: |
| 252 | kfree(buffer.pointer); |
| 253 | dev_dbg(&adap->dev, "Transaction status: %i\n", result); |
| 254 | return result; |
| 255 | } |
| 256 | |
| 257 | static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter) |
| 258 | { |
| 259 | struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data; |
| 260 | u32 ret; |
| 261 | |
| 262 | ret = smbus_cmi->cap_read | smbus_cmi->cap_write ? |
| 263 | I2C_FUNC_SMBUS_QUICK : 0; |
| 264 | |
| 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; |
| 270 | |
| 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; |
| 276 | |
| 277 | return ret; |
| 278 | } |
| 279 | |
| 280 | static const struct i2c_algorithm acpi_smbus_cmi_algorithm = { |
| 281 | .smbus_xfer = acpi_smbus_cmi_access, |
| 282 | .functionality = acpi_smbus_cmi_func, |
| 283 | }; |
| 284 | |
| 285 | |
| 286 | static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi, |
| 287 | const char *name) |
| 288 | { |
| 289 | struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; |
| 290 | union acpi_object *obj; |
| 291 | acpi_status status; |
| 292 | |
| 293 | if (!strcmp(name, smbus_methods.mt_info)) { |
| 294 | status = acpi_evaluate_object(smbus_cmi->handle, |
| 295 | smbus_methods.mt_info, |
| 296 | NULL, &buffer); |
| 297 | if (ACPI_FAILURE(status)) { |
| 298 | ACPI_ERROR((AE_INFO, "Evaluating %s: %i", |
| 299 | smbus_methods.mt_info, status)); |
| 300 | return -EIO; |
| 301 | } |
| 302 | |
| 303 | obj = buffer.pointer; |
| 304 | if (obj && obj->type == ACPI_TYPE_PACKAGE) |
| 305 | obj = obj->package.elements; |
| 306 | else { |
| 307 | ACPI_ERROR((AE_INFO, "Invalid argument type")); |
| 308 | kfree(buffer.pointer); |
| 309 | return -EIO; |
| 310 | } |
| 311 | |
| 312 | if (obj->type != ACPI_TYPE_INTEGER) { |
| 313 | ACPI_ERROR((AE_INFO, "Invalid argument type")); |
| 314 | kfree(buffer.pointer); |
| 315 | return -EIO; |
| 316 | } else |
| 317 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "SMBus CMI Version %x" |
| 318 | "\n", (int)obj->integer.value)); |
| 319 | |
| 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; |
| 326 | else |
| 327 | ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Unsupported CMI method: %s\n", |
| 328 | name)); |
| 329 | |
| 330 | return 0; |
| 331 | } |
| 332 | |
| 333 | static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level, |
| 334 | void *context, void **return_value) |
| 335 | { |
| 336 | char node_name[5]; |
| 337 | struct acpi_buffer buffer = { sizeof(node_name), node_name }; |
| 338 | struct acpi_smbus_cmi *smbus_cmi = context; |
| 339 | acpi_status status; |
| 340 | |
| 341 | status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); |
| 342 | |
| 343 | if (ACPI_SUCCESS(status)) |
| 344 | acpi_smbus_cmi_add_cap(smbus_cmi, node_name); |
| 345 | |
| 346 | return AE_OK; |
| 347 | } |
| 348 | |
| 349 | static int acpi_smbus_cmi_add(struct acpi_device *device) |
| 350 | { |
| 351 | struct acpi_smbus_cmi *smbus_cmi; |
| 352 | |
| 353 | smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL); |
| 354 | if (!smbus_cmi) |
| 355 | return -ENOMEM; |
| 356 | |
| 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; |
| 364 | |
| 365 | acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1, |
| 366 | acpi_smbus_cmi_query_methods, smbus_cmi, NULL); |
| 367 | |
| 368 | if (smbus_cmi->cap_info == 0) |
| 369 | goto err; |
| 370 | |
| 371 | snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name), |
Bjorn Helgaas | e96c928 | 2009-09-25 21:11:43 -0600 | [diff] [blame] | 372 | "SMBus CMI adapter %s", |
| 373 | acpi_device_name(device)); |
Crane Cai | dc98542 | 2009-09-18 22:45:51 +0200 | [diff] [blame] | 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; |
| 379 | |
| 380 | if (i2c_add_adapter(&smbus_cmi->adapter)) { |
| 381 | dev_err(&device->dev, "Couldn't register adapter!\n"); |
| 382 | goto err; |
| 383 | } |
| 384 | |
| 385 | return 0; |
| 386 | |
| 387 | err: |
| 388 | kfree(smbus_cmi); |
| 389 | device->driver_data = NULL; |
| 390 | return -EIO; |
| 391 | } |
| 392 | |
| 393 | static int acpi_smbus_cmi_remove(struct acpi_device *device, int type) |
| 394 | { |
| 395 | struct acpi_smbus_cmi *smbus_cmi = acpi_driver_data(device); |
| 396 | |
| 397 | i2c_del_adapter(&smbus_cmi->adapter); |
| 398 | kfree(smbus_cmi); |
| 399 | device->driver_data = NULL; |
| 400 | |
| 401 | return 0; |
| 402 | } |
| 403 | |
| 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, |
| 408 | .ops = { |
| 409 | .add = acpi_smbus_cmi_add, |
| 410 | .remove = acpi_smbus_cmi_remove, |
| 411 | }, |
| 412 | }; |
| 413 | |
| 414 | static int __init acpi_smbus_cmi_init(void) |
| 415 | { |
| 416 | return acpi_bus_register_driver(&acpi_smbus_cmi_driver); |
| 417 | } |
| 418 | |
| 419 | static void __exit acpi_smbus_cmi_exit(void) |
| 420 | { |
| 421 | acpi_bus_unregister_driver(&acpi_smbus_cmi_driver); |
| 422 | } |
| 423 | |
| 424 | module_init(acpi_smbus_cmi_init); |
| 425 | module_exit(acpi_smbus_cmi_exit); |
| 426 | |
| 427 | MODULE_LICENSE("GPL"); |
| 428 | MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>"); |
| 429 | MODULE_DESCRIPTION("ACPI SMBus CMI driver"); |