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