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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
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 {"", 0}
55};
56MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids);
57
58#define ACPI_SMBUS_STATUS_OK 0x00
59#define ACPI_SMBUS_STATUS_FAIL 0x07
60#define ACPI_SMBUS_STATUS_DNAK 0x10
61#define ACPI_SMBUS_STATUS_DERR 0x11
62#define ACPI_SMBUS_STATUS_CMD_DENY 0x12
63#define ACPI_SMBUS_STATUS_UNKNOWN 0x13
64#define ACPI_SMBUS_STATUS_ACC_DENY 0x17
65#define ACPI_SMBUS_STATUS_TIMEOUT 0x18
66#define ACPI_SMBUS_STATUS_NOTSUP 0x19
67#define ACPI_SMBUS_STATUS_BUSY 0x1a
68#define ACPI_SMBUS_STATUS_PEC 0x1f
69
70#define ACPI_SMBUS_PRTCL_WRITE 0x00
71#define ACPI_SMBUS_PRTCL_READ 0x01
72#define ACPI_SMBUS_PRTCL_QUICK 0x02
73#define ACPI_SMBUS_PRTCL_BYTE 0x04
74#define ACPI_SMBUS_PRTCL_BYTE_DATA 0x06
75#define ACPI_SMBUS_PRTCL_WORD_DATA 0x08
76#define ACPI_SMBUS_PRTCL_BLOCK_DATA 0x0a
77
78
79static int
80acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
81 char read_write, u8 command, int size,
82 union i2c_smbus_data *data)
83{
84 int result = 0;
85 struct acpi_smbus_cmi *smbus_cmi = adap->algo_data;
86 unsigned char protocol;
87 acpi_status status = 0;
88 struct acpi_object_list input;
89 union acpi_object mt_params[5];
90 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
91 union acpi_object *obj;
92 union acpi_object *pkg;
93 char *method;
94 int len = 0;
95
96 dev_dbg(&adap->dev, "access size: %d %s\n", size,
97 (read_write) ? "READ" : "WRITE");
98 switch (size) {
99 case I2C_SMBUS_QUICK:
100 protocol = ACPI_SMBUS_PRTCL_QUICK;
101 command = 0;
102 if (read_write == I2C_SMBUS_WRITE) {
103 mt_params[3].type = ACPI_TYPE_INTEGER;
104 mt_params[3].integer.value = 0;
105 mt_params[4].type = ACPI_TYPE_INTEGER;
106 mt_params[4].integer.value = 0;
107 }
108 break;
109
110 case I2C_SMBUS_BYTE:
111 protocol = ACPI_SMBUS_PRTCL_BYTE;
112 if (read_write == I2C_SMBUS_WRITE) {
113 mt_params[3].type = ACPI_TYPE_INTEGER;
114 mt_params[3].integer.value = 0;
115 mt_params[4].type = ACPI_TYPE_INTEGER;
116 mt_params[4].integer.value = 0;
117 } else {
118 command = 0;
119 }
120 break;
121
122 case I2C_SMBUS_BYTE_DATA:
123 protocol = ACPI_SMBUS_PRTCL_BYTE_DATA;
124 if (read_write == I2C_SMBUS_WRITE) {
125 mt_params[3].type = ACPI_TYPE_INTEGER;
126 mt_params[3].integer.value = 1;
127 mt_params[4].type = ACPI_TYPE_INTEGER;
128 mt_params[4].integer.value = data->byte;
129 }
130 break;
131
132 case I2C_SMBUS_WORD_DATA:
133 protocol = ACPI_SMBUS_PRTCL_WORD_DATA;
134 if (read_write == I2C_SMBUS_WRITE) {
135 mt_params[3].type = ACPI_TYPE_INTEGER;
136 mt_params[3].integer.value = 2;
137 mt_params[4].type = ACPI_TYPE_INTEGER;
138 mt_params[4].integer.value = data->word;
139 }
140 break;
141
142 case I2C_SMBUS_BLOCK_DATA:
143 protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA;
144 if (read_write == I2C_SMBUS_WRITE) {
145 len = data->block[0];
146 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
147 return -EINVAL;
148 mt_params[3].type = ACPI_TYPE_INTEGER;
149 mt_params[3].integer.value = len;
150 mt_params[4].type = ACPI_TYPE_BUFFER;
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_ERROR((AE_INFO, "Evaluating %s: %i", method, status));
182 return -EIO;
183 }
184
185 pkg = buffer.pointer;
186 if (pkg && pkg->type == ACPI_TYPE_PACKAGE)
187 obj = pkg->package.elements;
188 else {
189 ACPI_ERROR((AE_INFO, "Invalid argument type"));
190 result = -EIO;
191 goto out;
192 }
193 if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
194 ACPI_ERROR((AE_INFO, "Invalid argument type"));
195 result = -EIO;
196 goto out;
197 }
198
199 result = obj->integer.value;
200 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s return status: %i\n",
201 method, result));
202
203 switch (result) {
204 case ACPI_SMBUS_STATUS_OK:
205 result = 0;
206 break;
207 case ACPI_SMBUS_STATUS_BUSY:
208 result = -EBUSY;
209 goto out;
210 case ACPI_SMBUS_STATUS_TIMEOUT:
211 result = -ETIMEDOUT;
212 goto out;
213 case ACPI_SMBUS_STATUS_DNAK:
214 result = -ENXIO;
215 goto out;
216 default:
217 result = -EIO;
218 goto out;
219 }
220
221 if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK)
222 goto out;
223
224 obj = pkg->package.elements + 1;
225 if (obj->type != ACPI_TYPE_INTEGER) {
226 ACPI_ERROR((AE_INFO, "Invalid argument type"));
227 result = -EIO;
228 goto out;
229 }
230
231 len = obj->integer.value;
232 obj = pkg->package.elements + 2;
233 switch (size) {
234 case I2C_SMBUS_BYTE:
235 case I2C_SMBUS_BYTE_DATA:
236 case I2C_SMBUS_WORD_DATA:
237 if (obj->type != ACPI_TYPE_INTEGER) {
238 ACPI_ERROR((AE_INFO, "Invalid argument type"));
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_ERROR((AE_INFO, "Invalid argument type"));
250 result = -EIO;
251 goto out;
252 }
253 if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
254 return -EPROTO;
255 data->block[0] = len;
256 memcpy(data->block + 1, obj->buffer.pointer, len);
257 break;
258 }
259
260out:
261 kfree(buffer.pointer);
262 dev_dbg(&adap->dev, "Transaction status: %i\n", result);
263 return result;
264}
265
266static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter)
267{
268 struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data;
269 u32 ret;
270
271 ret = smbus_cmi->cap_read | smbus_cmi->cap_write ?
272 I2C_FUNC_SMBUS_QUICK : 0;
273
274 ret |= smbus_cmi->cap_read ?
275 (I2C_FUNC_SMBUS_READ_BYTE |
276 I2C_FUNC_SMBUS_READ_BYTE_DATA |
277 I2C_FUNC_SMBUS_READ_WORD_DATA |
278 I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0;
279
280 ret |= smbus_cmi->cap_write ?
281 (I2C_FUNC_SMBUS_WRITE_BYTE |
282 I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
283 I2C_FUNC_SMBUS_WRITE_WORD_DATA |
284 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0;
285
286 return ret;
287}
288
289static const struct i2c_algorithm acpi_smbus_cmi_algorithm = {
290 .smbus_xfer = acpi_smbus_cmi_access,
291 .functionality = acpi_smbus_cmi_func,
292};
293
294
295static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
296 const char *name)
297{
298 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
299 union acpi_object *obj;
300 acpi_status status;
301
302 if (!strcmp(name, smbus_cmi->methods->mt_info)) {
303 status = acpi_evaluate_object(smbus_cmi->handle,
304 smbus_cmi->methods->mt_info,
305 NULL, &buffer);
306 if (ACPI_FAILURE(status)) {
307 ACPI_ERROR((AE_INFO, "Evaluating %s: %i",
308 smbus_cmi->methods->mt_info, status));
309 return -EIO;
310 }
311
312 obj = buffer.pointer;
313 if (obj && obj->type == ACPI_TYPE_PACKAGE)
314 obj = obj->package.elements;
315 else {
316 ACPI_ERROR((AE_INFO, "Invalid argument type"));
317 kfree(buffer.pointer);
318 return -EIO;
319 }
320
321 if (obj->type != ACPI_TYPE_INTEGER) {
322 ACPI_ERROR((AE_INFO, "Invalid argument type"));
323 kfree(buffer.pointer);
324 return -EIO;
325 } else
326 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "SMBus CMI Version %x"
327 "\n", (int)obj->integer.value));
328
329 kfree(buffer.pointer);
330 smbus_cmi->cap_info = 1;
331 } else if (!strcmp(name, smbus_cmi->methods->mt_sbr))
332 smbus_cmi->cap_read = 1;
333 else if (!strcmp(name, smbus_cmi->methods->mt_sbw))
334 smbus_cmi->cap_write = 1;
335 else
336 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Unsupported CMI method: %s\n",
337 name));
338
339 return 0;
340}
341
342static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level,
343 void *context, void **return_value)
344{
345 char node_name[5];
346 struct acpi_buffer buffer = { sizeof(node_name), node_name };
347 struct acpi_smbus_cmi *smbus_cmi = context;
348 acpi_status status;
349
350 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
351
352 if (ACPI_SUCCESS(status))
353 acpi_smbus_cmi_add_cap(smbus_cmi, node_name);
354
355 return AE_OK;
356}
357
358static int acpi_smbus_cmi_add(struct acpi_device *device)
359{
360 struct acpi_smbus_cmi *smbus_cmi;
361 const struct acpi_device_id *id;
362
363 smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
364 if (!smbus_cmi)
365 return -ENOMEM;
366
367 smbus_cmi->handle = device->handle;
368 strcpy(acpi_device_name(device), ACPI_SMBUS_HC_DEVICE_NAME);
369 strcpy(acpi_device_class(device), ACPI_SMBUS_HC_CLASS);
370 device->driver_data = smbus_cmi;
371 smbus_cmi->cap_info = 0;
372 smbus_cmi->cap_read = 0;
373 smbus_cmi->cap_write = 0;
374
375 for (id = acpi_smbus_cmi_ids; id->id[0]; id++)
376 if (!strcmp(id->id, acpi_device_hid(device)))
377 smbus_cmi->methods =
378 (struct smbus_methods_t *) id->driver_data;
379
380 acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
381 acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);
382
383 if (smbus_cmi->cap_info == 0)
384 goto err;
385
386 snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name),
387 "SMBus CMI adapter %s",
388 acpi_device_name(device));
389 smbus_cmi->adapter.owner = THIS_MODULE;
390 smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm;
391 smbus_cmi->adapter.algo_data = smbus_cmi;
392 smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
393 smbus_cmi->adapter.dev.parent = &device->dev;
394
395 if (i2c_add_adapter(&smbus_cmi->adapter)) {
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 device->driver_data = NULL;
405 return -EIO;
406}
407
408static int acpi_smbus_cmi_remove(struct acpi_device *device)
409{
410 struct acpi_smbus_cmi *smbus_cmi = acpi_driver_data(device);
411
412 i2c_del_adapter(&smbus_cmi->adapter);
413 kfree(smbus_cmi);
414 device->driver_data = NULL;
415
416 return 0;
417}
418
419static struct acpi_driver acpi_smbus_cmi_driver = {
420 .name = ACPI_SMBUS_HC_DEVICE_NAME,
421 .class = ACPI_SMBUS_HC_CLASS,
422 .ids = acpi_smbus_cmi_ids,
423 .ops = {
424 .add = acpi_smbus_cmi_add,
425 .remove = acpi_smbus_cmi_remove,
426 },
427};
428module_acpi_driver(acpi_smbus_cmi_driver);
429
430MODULE_LICENSE("GPL");
431MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>");
432MODULE_DESCRIPTION("ACPI SMBus CMI driver");
433
