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