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-rw-r--r--drivers/i2c/i2c-core.c364
1 files changed, 364 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 632057a44615..ccfbbab82a15 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -27,6 +27,8 @@
27 OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de> 27 OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
28 (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and 28 (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and
29 (c) 2013 Wolfram Sang <wsa@the-dreams.de> 29 (c) 2013 Wolfram Sang <wsa@the-dreams.de>
30 I2C ACPI code Copyright (C) 2014 Intel Corp
31 Author: Lan Tianyu <tianyu.lan@intel.com>
30 */ 32 */
31 33
32#include <linux/module.h> 34#include <linux/module.h>
@@ -78,6 +80,368 @@ void i2c_transfer_trace_unreg(void)
78 static_key_slow_dec(&i2c_trace_msg); 80 static_key_slow_dec(&i2c_trace_msg);
79} 81}
80 82
83#if defined(CONFIG_ACPI)
84struct acpi_i2c_handler_data {
85 struct acpi_connection_info info;
86 struct i2c_adapter *adapter;
87};
88
89struct gsb_buffer {
90 u8 status;
91 u8 len;
92 union {
93 u16 wdata;
94 u8 bdata;
95 u8 data[0];
96 };
97} __packed;
98
99static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
100{
101 struct i2c_board_info *info = data;
102
103 if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
104 struct acpi_resource_i2c_serialbus *sb;
105
106 sb = &ares->data.i2c_serial_bus;
107 if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
108 info->addr = sb->slave_address;
109 if (sb->access_mode == ACPI_I2C_10BIT_MODE)
110 info->flags |= I2C_CLIENT_TEN;
111 }
112 } else if (info->irq < 0) {
113 struct resource r;
114
115 if (acpi_dev_resource_interrupt(ares, 0, &r))
116 info->irq = r.start;
117 }
118
119 /* Tell the ACPI core to skip this resource */
120 return 1;
121}
122
123static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
124 void *data, void **return_value)
125{
126 struct i2c_adapter *adapter = data;
127 struct list_head resource_list;
128 struct i2c_board_info info;
129 struct acpi_device *adev;
130 int ret;
131
132 if (acpi_bus_get_device(handle, &adev))
133 return AE_OK;
134 if (acpi_bus_get_status(adev) || !adev->status.present)
135 return AE_OK;
136
137 memset(&info, 0, sizeof(info));
138 info.acpi_node.companion = adev;
139 info.irq = -1;
140
141 INIT_LIST_HEAD(&resource_list);
142 ret = acpi_dev_get_resources(adev, &resource_list,
143 acpi_i2c_add_resource, &info);
144 acpi_dev_free_resource_list(&resource_list);
145
146 if (ret < 0 || !info.addr)
147 return AE_OK;
148
149 adev->power.flags.ignore_parent = true;
150 strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
151 if (!i2c_new_device(adapter, &info)) {
152 adev->power.flags.ignore_parent = false;
153 dev_err(&adapter->dev,
154 "failed to add I2C device %s from ACPI\n",
155 dev_name(&adev->dev));
156 }
157
158 return AE_OK;
159}
160
161/**
162 * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
163 * @adap: pointer to adapter
164 *
165 * Enumerate all I2C slave devices behind this adapter by walking the ACPI
166 * namespace. When a device is found it will be added to the Linux device
167 * model and bound to the corresponding ACPI handle.
168 */
169static void acpi_i2c_register_devices(struct i2c_adapter *adap)
170{
171 acpi_handle handle;
172 acpi_status status;
173
174 if (!adap->dev.parent)
175 return;
176
177 handle = ACPI_HANDLE(adap->dev.parent);
178 if (!handle)
179 return;
180
181 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
182 acpi_i2c_add_device, NULL,
183 adap, NULL);
184 if (ACPI_FAILURE(status))
185 dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
186}
187
188#else /* CONFIG_ACPI */
189static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { }
190#endif /* CONFIG_ACPI */
191
192#ifdef CONFIG_ACPI_I2C_OPREGION
193static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
194 u8 cmd, u8 *data, u8 data_len)
195{
196
197 struct i2c_msg msgs[2];
198 int ret;
199 u8 *buffer;
200
201 buffer = kzalloc(data_len, GFP_KERNEL);
202 if (!buffer)
203 return AE_NO_MEMORY;
204
205 msgs[0].addr = client->addr;
206 msgs[0].flags = client->flags;
207 msgs[0].len = 1;
208 msgs[0].buf = &cmd;
209
210 msgs[1].addr = client->addr;
211 msgs[1].flags = client->flags | I2C_M_RD;
212 msgs[1].len = data_len;
213 msgs[1].buf = buffer;
214
215 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
216 if (ret < 0)
217 dev_err(&client->adapter->dev, "i2c read failed\n");
218 else
219 memcpy(data, buffer, data_len);
220
221 kfree(buffer);
222 return ret;
223}
224
225static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
226 u8 cmd, u8 *data, u8 data_len)
227{
228
229 struct i2c_msg msgs[1];
230 u8 *buffer;
231 int ret = AE_OK;
232
233 buffer = kzalloc(data_len + 1, GFP_KERNEL);
234 if (!buffer)
235 return AE_NO_MEMORY;
236
237 buffer[0] = cmd;
238 memcpy(buffer + 1, data, data_len);
239
240 msgs[0].addr = client->addr;
241 msgs[0].flags = client->flags;
242 msgs[0].len = data_len + 1;
243 msgs[0].buf = buffer;
244
245 ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
246 if (ret < 0)
247 dev_err(&client->adapter->dev, "i2c write failed\n");
248
249 kfree(buffer);
250 return ret;
251}
252
253static acpi_status
254acpi_i2c_space_handler(u32 function, acpi_physical_address command,
255 u32 bits, u64 *value64,
256 void *handler_context, void *region_context)
257{
258 struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
259 struct acpi_i2c_handler_data *data = handler_context;
260 struct acpi_connection_info *info = &data->info;
261 struct acpi_resource_i2c_serialbus *sb;
262 struct i2c_adapter *adapter = data->adapter;
263 struct i2c_client client;
264 struct acpi_resource *ares;
265 u32 accessor_type = function >> 16;
266 u8 action = function & ACPI_IO_MASK;
267 acpi_status ret = AE_OK;
268 int status;
269
270 ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
271 if (ACPI_FAILURE(ret))
272 return ret;
273
274 if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
275 ret = AE_BAD_PARAMETER;
276 goto err;
277 }
278
279 sb = &ares->data.i2c_serial_bus;
280 if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
281 ret = AE_BAD_PARAMETER;
282 goto err;
283 }
284
285 memset(&client, 0, sizeof(client));
286 client.adapter = adapter;
287 client.addr = sb->slave_address;
288 client.flags = 0;
289
290 if (sb->access_mode == ACPI_I2C_10BIT_MODE)
291 client.flags |= I2C_CLIENT_TEN;
292
293 switch (accessor_type) {
294 case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
295 if (action == ACPI_READ) {
296 status = i2c_smbus_read_byte(&client);
297 if (status >= 0) {
298 gsb->bdata = status;
299 status = 0;
300 }
301 } else {
302 status = i2c_smbus_write_byte(&client, gsb->bdata);
303 }
304 break;
305
306 case ACPI_GSB_ACCESS_ATTRIB_BYTE:
307 if (action == ACPI_READ) {
308 status = i2c_smbus_read_byte_data(&client, command);
309 if (status >= 0) {
310 gsb->bdata = status;
311 status = 0;
312 }
313 } else {
314 status = i2c_smbus_write_byte_data(&client, command,
315 gsb->bdata);
316 }
317 break;
318
319 case ACPI_GSB_ACCESS_ATTRIB_WORD:
320 if (action == ACPI_READ) {
321 status = i2c_smbus_read_word_data(&client, command);
322 if (status >= 0) {
323 gsb->wdata = status;
324 status = 0;
325 }
326 } else {
327 status = i2c_smbus_write_word_data(&client, command,
328 gsb->wdata);
329 }
330 break;
331
332 case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
333 if (action == ACPI_READ) {
334 status = i2c_smbus_read_block_data(&client, command,
335 gsb->data);
336 if (status >= 0) {
337 gsb->len = status;
338 status = 0;
339 }
340 } else {
341 status = i2c_smbus_write_block_data(&client, command,
342 gsb->len, gsb->data);
343 }
344 break;
345
346 case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
347 if (action == ACPI_READ) {
348 status = acpi_gsb_i2c_read_bytes(&client, command,
349 gsb->data, info->access_length);
350 if (status > 0)
351 status = 0;
352 } else {
353 status = acpi_gsb_i2c_write_bytes(&client, command,
354 gsb->data, info->access_length);
355 }
356 break;
357
358 default:
359 pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
360 ret = AE_BAD_PARAMETER;
361 goto err;
362 }
363
364 gsb->status = status;
365
366 err:
367 ACPI_FREE(ares);
368 return ret;
369}
370
371
372static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
373{
374 acpi_handle handle;
375 struct acpi_i2c_handler_data *data;
376 acpi_status status;
377
378 if (!adapter->dev.parent)
379 return -ENODEV;
380
381 handle = ACPI_HANDLE(adapter->dev.parent);
382
383 if (!handle)
384 return -ENODEV;
385
386 data = kzalloc(sizeof(struct acpi_i2c_handler_data),
387 GFP_KERNEL);
388 if (!data)
389 return -ENOMEM;
390
391 data->adapter = adapter;
392 status = acpi_bus_attach_private_data(handle, (void *)data);
393 if (ACPI_FAILURE(status)) {
394 kfree(data);
395 return -ENOMEM;
396 }
397
398 status = acpi_install_address_space_handler(handle,
399 ACPI_ADR_SPACE_GSBUS,
400 &acpi_i2c_space_handler,
401 NULL,
402 data);
403 if (ACPI_FAILURE(status)) {
404 dev_err(&adapter->dev, "Error installing i2c space handler\n");
405 acpi_bus_detach_private_data(handle);
406 kfree(data);
407 return -ENOMEM;
408 }
409
410 return 0;
411}
412
413static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
414{
415 acpi_handle handle;
416 struct acpi_i2c_handler_data *data;
417 acpi_status status;
418
419 if (!adapter->dev.parent)
420 return;
421
422 handle = ACPI_HANDLE(adapter->dev.parent);
423
424 if (!handle)
425 return;
426
427 acpi_remove_address_space_handler(handle,
428 ACPI_ADR_SPACE_GSBUS,
429 &acpi_i2c_space_handler);
430
431 status = acpi_bus_get_private_data(handle, (void **)&data);
432 if (ACPI_SUCCESS(status))
433 kfree(data);
434
435 acpi_bus_detach_private_data(handle);
436}
437#else /* CONFIG_ACPI_I2C_OPREGION */
438static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
439{ }
440
441static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
442{ return 0; }
443#endif /* CONFIG_ACPI_I2C_OPREGION */
444
81/* ------------------------------------------------------------------------- */ 445/* ------------------------------------------------------------------------- */
82 446
83static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, 447static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,