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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
19#define ACPI_SMBUS_MS_HID "SMB0001"
20
21ACPI_MODULE_NAME("smbus_cmi");
22
23struct smbus_methods_t {
24 char *mt_info;
25 char *mt_sbr;
26 char *mt_sbw;
27};
28
29struct acpi_smbus_cmi {
30 acpi_handle handle;
31 struct i2c_adapter adapter;
32 u8 cap_info:1;
33 u8 cap_read:1;
34 u8 cap_write:1;
35 struct smbus_methods_t *methods;
36};
37
38static const struct smbus_methods_t smbus_methods = {
39 .mt_info = "_SBI",
40 .mt_sbr = "_SBR",
41 .mt_sbw = "_SBW",
42};
43
44
45static const struct smbus_methods_t ibm_smbus_methods = {
46 .mt_info = "SBI_",
47 .mt_sbr = "SBR_",
48 .mt_sbw = "SBW_",
49};
50
51static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
52 {"SMBUS01", (kernel_ulong_t)&smbus_methods},
53 {ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods},
54 {ACPI_SMBUS_MS_HID, (kernel_ulong_t)&smbus_methods},
55 {"", 0}
56};
57MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids);
58
59#define ACPI_SMBUS_STATUS_OK 0x00
60#define ACPI_SMBUS_STATUS_FAIL 0x07
61#define ACPI_SMBUS_STATUS_DNAK 0x10
62#define ACPI_SMBUS_STATUS_DERR 0x11
63#define ACPI_SMBUS_STATUS_CMD_DENY 0x12
64#define ACPI_SMBUS_STATUS_UNKNOWN 0x13
65#define ACPI_SMBUS_STATUS_ACC_DENY 0x17
66#define ACPI_SMBUS_STATUS_TIMEOUT 0x18
67#define ACPI_SMBUS_STATUS_NOTSUP 0x19
68#define ACPI_SMBUS_STATUS_BUSY 0x1a
69#define ACPI_SMBUS_STATUS_PEC 0x1f
70
71#define ACPI_SMBUS_PRTCL_WRITE 0x00
72#define ACPI_SMBUS_PRTCL_READ 0x01
73#define ACPI_SMBUS_PRTCL_QUICK 0x02
74#define ACPI_SMBUS_PRTCL_BYTE 0x04
75#define ACPI_SMBUS_PRTCL_BYTE_DATA 0x06
76#define ACPI_SMBUS_PRTCL_WORD_DATA 0x08
77#define ACPI_SMBUS_PRTCL_BLOCK_DATA 0x0a
78
79
80static int
81acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
82 char read_write, u8 command, int size,
83 union i2c_smbus_data *data)
84{
85 int result = 0;
86 struct acpi_smbus_cmi *smbus_cmi = adap->algo_data;
87 unsigned char protocol;
88 acpi_status status = 0;
89 struct acpi_object_list input;
90 union acpi_object mt_params[5];
91 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
92 union acpi_object *obj;
93 union acpi_object *pkg;
94 char *method;
95 int len = 0;
96
97 dev_dbg(&adap->dev, "access size: %d %s\n", size,
98 (read_write) ? "READ" : "WRITE");
99 switch (size) {
100 case I2C_SMBUS_QUICK:
101 protocol = ACPI_SMBUS_PRTCL_QUICK;
102 command = 0;
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 }
109 break;
110
111 case I2C_SMBUS_BYTE:
112 protocol = ACPI_SMBUS_PRTCL_BYTE;
113 if (read_write == I2C_SMBUS_WRITE) {
114 mt_params[3].type = ACPI_TYPE_INTEGER;
115 mt_params[3].integer.value = 0;
116 mt_params[4].type = ACPI_TYPE_INTEGER;
117 mt_params[4].integer.value = 0;
118 } else {
119 command = 0;
120 }
121 break;
122
123 case I2C_SMBUS_BYTE_DATA:
124 protocol = ACPI_SMBUS_PRTCL_BYTE_DATA;
125 if (read_write == I2C_SMBUS_WRITE) {
126 mt_params[3].type = ACPI_TYPE_INTEGER;
127 mt_params[3].integer.value = 1;
128 mt_params[4].type = ACPI_TYPE_INTEGER;
129 mt_params[4].integer.value = data->byte;
130 }
131 break;
132
133 case I2C_SMBUS_WORD_DATA:
134 protocol = ACPI_SMBUS_PRTCL_WORD_DATA;
135 if (read_write == I2C_SMBUS_WRITE) {
136 mt_params[3].type = ACPI_TYPE_INTEGER;
137 mt_params[3].integer.value = 2;
138 mt_params[4].type = ACPI_TYPE_INTEGER;
139 mt_params[4].integer.value = data->word;
140 }
141 break;
142
143 case I2C_SMBUS_BLOCK_DATA:
144 protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA;
145 if (read_write == I2C_SMBUS_WRITE) {
146 len = data->block[0];
147 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
148 return -EINVAL;
149 mt_params[3].type = ACPI_TYPE_INTEGER;
150 mt_params[3].integer.value = len;
151 mt_params[4].type = ACPI_TYPE_BUFFER;
152 mt_params[4].buffer.length = len;
153 mt_params[4].buffer.pointer = data->block + 1;
154 }
155 break;
156
157 default:
158 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
159 return -EOPNOTSUPP;
160 }
161
162 if (read_write == I2C_SMBUS_READ) {
163 protocol |= ACPI_SMBUS_PRTCL_READ;
164 method = smbus_cmi->methods->mt_sbr;
165 input.count = 3;
166 } else {
167 protocol |= ACPI_SMBUS_PRTCL_WRITE;
168 method = smbus_cmi->methods->mt_sbw;
169 input.count = 5;
170 }
171
172 input.pointer = mt_params;
173 mt_params[0].type = ACPI_TYPE_INTEGER;
174 mt_params[0].integer.value = protocol;
175 mt_params[1].type = ACPI_TYPE_INTEGER;
176 mt_params[1].integer.value = addr;
177 mt_params[2].type = ACPI_TYPE_INTEGER;
178 mt_params[2].integer.value = command;
179
180 status = acpi_evaluate_object(smbus_cmi->handle, method, &input,
181 &buffer);
182 if (ACPI_FAILURE(status)) {
183 acpi_handle_err(smbus_cmi->handle,
184 "Failed to evaluate %s: %i\n", method, status);
185 return -EIO;
186 }
187
188 pkg = buffer.pointer;
189 if (pkg && pkg->type == ACPI_TYPE_PACKAGE)
190 obj = pkg->package.elements;
191 else {
192 acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
193 result = -EIO;
194 goto out;
195 }
196 if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
197 acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
198 result = -EIO;
199 goto out;
200 }
201
202 result = obj->integer.value;
203 acpi_handle_debug(smbus_cmi->handle, "%s return status: %i\n", method,
204 result);
205
206 switch (result) {
207 case ACPI_SMBUS_STATUS_OK:
208 result = 0;
209 break;
210 case ACPI_SMBUS_STATUS_BUSY:
211 result = -EBUSY;
212 goto out;
213 case ACPI_SMBUS_STATUS_TIMEOUT:
214 result = -ETIMEDOUT;
215 goto out;
216 case ACPI_SMBUS_STATUS_DNAK:
217 result = -ENXIO;
218 goto out;
219 default:
220 result = -EIO;
221 goto out;
222 }
223
224 if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK)
225 goto out;
226
227 obj = pkg->package.elements + 1;
228 if (obj->type != ACPI_TYPE_INTEGER) {
229 acpi_handle_err(smbus_cmi->handle, "Invalid argument type\n");
230 result = -EIO;
231 goto out;
232 }
233
234 len = obj->integer.value;
235 obj = pkg->package.elements + 2;
236 switch (size) {
237 case I2C_SMBUS_BYTE:
238 case I2C_SMBUS_BYTE_DATA:
239 case I2C_SMBUS_WORD_DATA:
240 if (obj->type != ACPI_TYPE_INTEGER) {
241 acpi_handle_err(smbus_cmi->handle,
242 "Invalid argument type\n");
243 result = -EIO;
244 goto out;
245 }
246 if (len == 2)
247 data->word = obj->integer.value;
248 else
249 data->byte = obj->integer.value;
250 break;
251 case I2C_SMBUS_BLOCK_DATA:
252 if (obj->type != ACPI_TYPE_BUFFER) {
253 acpi_handle_err(smbus_cmi->handle,
254 "Invalid argument type\n");
255 result = -EIO;
256 goto out;
257 }
258 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
259 return -EPROTO;
260 data->block[0] = len;
261 memcpy(data->block + 1, obj->buffer.pointer, len);
262 break;
263 }
264
265out:
266 kfree(buffer.pointer);
267 dev_dbg(&adap->dev, "Transaction status: %i\n", result);
268 return result;
269}
270
271static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter)
272{
273 struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data;
274 u32 ret;
275
276 ret = smbus_cmi->cap_read | smbus_cmi->cap_write ?
277 I2C_FUNC_SMBUS_QUICK : 0;
278
279 ret |= smbus_cmi->cap_read ?
280 (I2C_FUNC_SMBUS_READ_BYTE |
281 I2C_FUNC_SMBUS_READ_BYTE_DATA |
282 I2C_FUNC_SMBUS_READ_WORD_DATA |
283 I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0;
284
285 ret |= smbus_cmi->cap_write ?
286 (I2C_FUNC_SMBUS_WRITE_BYTE |
287 I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
288 I2C_FUNC_SMBUS_WRITE_WORD_DATA |
289 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0;
290
291 return ret;
292}
293
294static const struct i2c_algorithm acpi_smbus_cmi_algorithm = {
295 .smbus_xfer = acpi_smbus_cmi_access,
296 .functionality = acpi_smbus_cmi_func,
297};
298
299
300static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
301 const char *name)
302{
303 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
304 struct acpi_handle *handle = smbus_cmi->handle;
305 union acpi_object *obj;
306 acpi_status status;
307
308 if (!strcmp(name, smbus_cmi->methods->mt_info)) {
309 status = acpi_evaluate_object(smbus_cmi->handle,
310 smbus_cmi->methods->mt_info,
311 NULL, &buffer);
312 if (ACPI_FAILURE(status)) {
313 acpi_handle_err(handle, "Failed to evaluate %s: %i\n",
314 smbus_cmi->methods->mt_info, status);
315 return -EIO;
316 }
317
318 obj = buffer.pointer;
319 if (obj && obj->type == ACPI_TYPE_PACKAGE)
320 obj = obj->package.elements;
321 else {
322 acpi_handle_err(handle, "Invalid argument type\n");
323 kfree(buffer.pointer);
324 return -EIO;
325 }
326
327 if (obj->type != ACPI_TYPE_INTEGER) {
328 acpi_handle_err(handle, "Invalid argument type\n");
329 kfree(buffer.pointer);
330 return -EIO;
331 } else
332 acpi_handle_debug(handle, "SMBus CMI Version %x\n",
333 (int)obj->integer.value);
334
335 kfree(buffer.pointer);
336 smbus_cmi->cap_info = 1;
337 } else if (!strcmp(name, smbus_cmi->methods->mt_sbr))
338 smbus_cmi->cap_read = 1;
339 else if (!strcmp(name, smbus_cmi->methods->mt_sbw))
340 smbus_cmi->cap_write = 1;
341 else
342 acpi_handle_debug(handle, "Unsupported CMI method: %s\n", name);
343
344 return 0;
345}
346
347static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level,
348 void *context, void **return_value)
349{
350 char node_name[5];
351 struct acpi_buffer buffer = { sizeof(node_name), node_name };
352 struct acpi_smbus_cmi *smbus_cmi = context;
353 acpi_status status;
354
355 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
356
357 if (ACPI_SUCCESS(status))
358 acpi_smbus_cmi_add_cap(smbus_cmi, node_name);
359
360 return AE_OK;
361}
362
363static int acpi_smbus_cmi_add(struct acpi_device *device)
364{
365 struct acpi_smbus_cmi *smbus_cmi;
366 const struct acpi_device_id *id;
367 int ret;
368
369 smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
370 if (!smbus_cmi)
371 return -ENOMEM;
372
373 smbus_cmi->handle = device->handle;
374 strcpy(acpi_device_name(device), ACPI_SMBUS_HC_DEVICE_NAME);
375 strcpy(acpi_device_class(device), ACPI_SMBUS_HC_CLASS);
376 device->driver_data = smbus_cmi;
377 smbus_cmi->cap_info = 0;
378 smbus_cmi->cap_read = 0;
379 smbus_cmi->cap_write = 0;
380
381 for (id = acpi_smbus_cmi_ids; id->id[0]; id++)
382 if (!strcmp(id->id, acpi_device_hid(device)))
383 smbus_cmi->methods =
384 (struct smbus_methods_t *) id->driver_data;
385
386 acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
387 acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);
388
389 if (smbus_cmi->cap_info == 0) {
390 ret = -ENODEV;
391 goto err;
392 }
393
394 snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name),
395 "SMBus CMI adapter %s",
396 acpi_device_name(device));
397 smbus_cmi->adapter.owner = THIS_MODULE;
398 smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm;
399 smbus_cmi->adapter.algo_data = smbus_cmi;
400 smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
401 smbus_cmi->adapter.dev.parent = &device->dev;
402
403 ret = i2c_add_adapter(&smbus_cmi->adapter);
404 if (ret) {
405 dev_err(&device->dev, "Couldn't register adapter!\n");
406 goto err;
407 }
408
409 return 0;
410
411err:
412 kfree(smbus_cmi);
413 device->driver_data = NULL;
414 return ret;
415}
416
417static int acpi_smbus_cmi_remove(struct acpi_device *device)
418{
419 struct acpi_smbus_cmi *smbus_cmi = acpi_driver_data(device);
420
421 i2c_del_adapter(&smbus_cmi->adapter);
422 kfree(smbus_cmi);
423 device->driver_data = NULL;
424
425 return 0;
426}
427
428static struct acpi_driver acpi_smbus_cmi_driver = {
429 .name = ACPI_SMBUS_HC_DEVICE_NAME,
430 .class = ACPI_SMBUS_HC_CLASS,
431 .ids = acpi_smbus_cmi_ids,
432 .ops = {
433 .add = acpi_smbus_cmi_add,
434 .remove = acpi_smbus_cmi_remove,
435 },
436};
437module_acpi_driver(acpi_smbus_cmi_driver);
438
439MODULE_LICENSE("GPL");
440MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>");
441MODULE_DESCRIPTION("ACPI SMBus CMI driver");
442
