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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / drivers / i2c / busses / i2c-powermac.c
blobf2a2067525efb1c3c1bb9b317ba136586b03aed9
1 /*
2 i2c Support for Apple SMU Controller
3
4 Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp.
5 <benh@kernel.crashing.org>
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 */
18
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/types.h>
22 #include <linux/i2c.h>
23 #include <linux/device.h>
24 #include <linux/platform_device.h>
25 #include <linux/of_irq.h>
26 #include <asm/prom.h>
27 #include <asm/pmac_low_i2c.h>
28
29 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
30 MODULE_DESCRIPTION("I2C driver for Apple PowerMac");
31 MODULE_LICENSE("GPL");
32
33 /*
34 * SMBUS-type transfer entrypoint
35 */
36 static s32 i2c_powermac_smbus_xfer( struct i2c_adapter* adap,
37 u16 addr,
38 unsigned short flags,
39 char read_write,
40 u8 command,
41 int size,
42 union i2c_smbus_data* data)
43 {
44 struct pmac_i2c_bus *bus = i2c_get_adapdata(adap);
45 int rc = 0;
46 int read = (read_write == I2C_SMBUS_READ);
47 int addrdir = (addr << 1) | read;
48 int mode, subsize, len;
49 u32 subaddr;
50 u8 *buf;
51 u8 local[2];
52
53 if (size == I2C_SMBUS_QUICK || size == I2C_SMBUS_BYTE) {
54 mode = pmac_i2c_mode_std;
55 subsize = 0;
56 subaddr = 0;
57 } else {
58 mode = read ? pmac_i2c_mode_combined : pmac_i2c_mode_stdsub;
59 subsize = 1;
60 subaddr = command;
61 }
62
63 switch (size) {
64 case I2C_SMBUS_QUICK:
65 buf = NULL;
66 len = 0;
67 break;
68 case I2C_SMBUS_BYTE:
69 case I2C_SMBUS_BYTE_DATA:
70 buf = &data->byte;
71 len = 1;
72 break;
73 case I2C_SMBUS_WORD_DATA:
74 if (!read) {
75 local[0] = data->word & 0xff;
76 local[1] = (data->word >> 8) & 0xff;
77 }
78 buf = local;
79 len = 2;
80 break;
81
82 /* Note that these are broken vs. the expected smbus API where
83 * on reads, the length is actually returned from the function,
84 * but I think the current API makes no sense and I don't want
85 * any driver that I haven't verified for correctness to go
86 * anywhere near a pmac i2c bus anyway ...
87 *
88 * I'm also not completely sure what kind of phases to do between
89 * the actual command and the data (what I am _supposed_ to do that
90 * is). For now, I assume writes are a single stream and reads have
91 * a repeat start/addr phase (but not stop in between)
92 */
93 case I2C_SMBUS_BLOCK_DATA:
94 buf = data->block;
95 len = data->block[0] + 1;
96 break;
97 case I2C_SMBUS_I2C_BLOCK_DATA:
98 buf = &data->block[1];
99 len = data->block[0];
100 break;
101
102 default:
103 return -EINVAL;
104 }
105
106 rc = pmac_i2c_open(bus, 0);
107 if (rc) {
108 dev_err(&adap->dev, "Failed to open I2C, err %d\n", rc);
109 return rc;
110 }
111
112 rc = pmac_i2c_setmode(bus, mode);
113 if (rc) {
114 dev_err(&adap->dev, "Failed to set I2C mode %d, err %d\n",
115 mode, rc);
116 goto bail;
117 }
118
119 rc = pmac_i2c_xfer(bus, addrdir, subsize, subaddr, buf, len);
120 if (rc) {
121 if (rc == -ENXIO)
122 dev_dbg(&adap->dev,
123 "I2C transfer at 0x%02x failed, size %d, "
124 "err %d\n", addrdir >> 1, size, rc);
125 else
126 dev_err(&adap->dev,
127 "I2C transfer at 0x%02x failed, size %d, "
128 "err %d\n", addrdir >> 1, size, rc);
129 goto bail;
130 }
131
132 if (size == I2C_SMBUS_WORD_DATA && read) {
133 data->word = ((u16)local[1]) << 8;
134 data->word |= local[0];
135 }
136
137 bail:
138 pmac_i2c_close(bus);
139 return rc;
140 }
141
142 /*
143 * Generic i2c master transfer entrypoint. This driver only support single
144 * messages (for "lame i2c" transfers). Anything else should use the smbus
145 * entry point
146 */
147 static int i2c_powermac_master_xfer( struct i2c_adapter *adap,
148 struct i2c_msg *msgs,
149 int num)
150 {
151 struct pmac_i2c_bus *bus = i2c_get_adapdata(adap);
152 int rc = 0;
153 int addrdir;
154
155 if (msgs->flags & I2C_M_TEN)
156 return -EINVAL;
157 addrdir = i2c_8bit_addr_from_msg(msgs);
158
159 rc = pmac_i2c_open(bus, 0);
160 if (rc) {
161 dev_err(&adap->dev, "Failed to open I2C, err %d\n", rc);
162 return rc;
163 }
164 rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std);
165 if (rc) {
166 dev_err(&adap->dev, "Failed to set I2C mode %d, err %d\n",
167 pmac_i2c_mode_std, rc);
168 goto bail;
169 }
170 rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len);
171 if (rc < 0) {
172 if (rc == -ENXIO)
173 dev_dbg(&adap->dev, "I2C %s 0x%02x failed, err %d\n",
174 addrdir & 1 ? "read from" : "write to",
175 addrdir >> 1, rc);
176 else
177 dev_err(&adap->dev, "I2C %s 0x%02x failed, err %d\n",
178 addrdir & 1 ? "read from" : "write to",
179 addrdir >> 1, rc);
180 }
181 bail:
182 pmac_i2c_close(bus);
183 return rc < 0 ? rc : 1;
184 }
185
186 static u32 i2c_powermac_func(struct i2c_adapter * adapter)
187 {
188 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
189 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
190 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_I2C;
191 }
192
193 /* For now, we only handle smbus */
194 static const struct i2c_algorithm i2c_powermac_algorithm = {
195 .smbus_xfer = i2c_powermac_smbus_xfer,
196 .master_xfer = i2c_powermac_master_xfer,
197 .functionality = i2c_powermac_func,
198 };
199
200 static const struct i2c_adapter_quirks i2c_powermac_quirks = {
201 .max_num_msgs = 1,
202 };
203
204 static int i2c_powermac_remove(struct platform_device *dev)
205 {
206 struct i2c_adapter *adapter = platform_get_drvdata(dev);
207
208 i2c_del_adapter(adapter);
209 memset(adapter, 0, sizeof(*adapter));
210
211 return 0;
212 }
213
214 static u32 i2c_powermac_get_addr(struct i2c_adapter *adap,
215 struct pmac_i2c_bus *bus,
216 struct device_node *node)
217 {
218 const __be32 *prop;
219 int len;
220
221 /* First check for valid "reg" */
222 prop = of_get_property(node, "reg", &len);
223 if (prop && (len >= sizeof(int)))
224 return (be32_to_cpup(prop) & 0xff) >> 1;
225
226 /* Then check old-style "i2c-address" */
227 prop = of_get_property(node, "i2c-address", &len);
228 if (prop && (len >= sizeof(int)))
229 return (be32_to_cpup(prop) & 0xff) >> 1;
230
231 /* Now handle some devices with missing "reg" properties */
232 if (!strcmp(node->name, "cereal"))
233 return 0x60;
234 else if (!strcmp(node->name, "deq"))
235 return 0x34;
236
237 dev_warn(&adap->dev, "No i2c address for %pOF\n", node);
238
239 return 0xffffffff;
240 }
241
242 static void i2c_powermac_create_one(struct i2c_adapter *adap,
243 const char *type,
244 u32 addr)
245 {
246 struct i2c_board_info info = {};
247 struct i2c_client *newdev;
248
249 strncpy(info.type, type, sizeof(info.type));
250 info.addr = addr;
251 newdev = i2c_new_device(adap, &info);
252 if (!newdev)
253 dev_err(&adap->dev,
254 "i2c-powermac: Failure to register missing %s\n",
255 type);
256 }
257
258 static void i2c_powermac_add_missing(struct i2c_adapter *adap,
259 struct pmac_i2c_bus *bus,
260 bool found_onyx)
261 {
262 struct device_node *busnode = pmac_i2c_get_bus_node(bus);
263 int rc;
264
265 /* Check for the onyx audio codec */
266 #define ONYX_REG_CONTROL 67
267 if (of_device_is_compatible(busnode, "k2-i2c") && !found_onyx) {
268 union i2c_smbus_data data;
269
270 rc = i2c_smbus_xfer(adap, 0x46, 0, I2C_SMBUS_READ,
271 ONYX_REG_CONTROL, I2C_SMBUS_BYTE_DATA,
272 &data);
273 if (rc >= 0)
274 i2c_powermac_create_one(adap, "MAC,pcm3052", 0x46);
275
276 rc = i2c_smbus_xfer(adap, 0x47, 0, I2C_SMBUS_READ,
277 ONYX_REG_CONTROL, I2C_SMBUS_BYTE_DATA,
278 &data);
279 if (rc >= 0)
280 i2c_powermac_create_one(adap, "MAC,pcm3052", 0x47);
281 }
282 }
283
284 static bool i2c_powermac_get_type(struct i2c_adapter *adap,
285 struct device_node *node,
286 u32 addr, char *type, int type_size)
287 {
288 char tmp[16];
289
290 /* Note: we to _NOT_ want the standard
291 * i2c drivers to match with any of our powermac stuff
292 * unless they have been specifically modified to handle
293 * it on a case by case basis. For example, for thermal
294 * control, things like lm75 etc... shall match with their
295 * corresponding windfarm drivers, _NOT_ the generic ones,
296 * so we force a prefix of AAPL, onto the modalias to
297 * make that happen
298 */
299
300 /* First try proper modalias */
301 if (of_modalias_node(node, tmp, sizeof(tmp)) >= 0) {
302 snprintf(type, type_size, "MAC,%s", tmp);
303 return true;
304 }
305
306 /* Now look for known workarounds */
307 if (!strcmp(node->name, "deq")) {
308 /* Apple uses address 0x34 for TAS3001 and 0x35 for TAS3004 */
309 if (addr == 0x34) {
310 snprintf(type, type_size, "MAC,tas3001");
311 return true;
312 } else if (addr == 0x35) {
313 snprintf(type, type_size, "MAC,tas3004");
314 return true;
315 }
316 }
317
318 dev_err(&adap->dev, "i2c-powermac: modalias failure on %pOF\n", node);
319 return false;
320 }
321
322 static void i2c_powermac_register_devices(struct i2c_adapter *adap,
323 struct pmac_i2c_bus *bus)
324 {
325 struct i2c_client *newdev;
326 struct device_node *node;
327 bool found_onyx = 0;
328
329 /*
330 * In some cases we end up with the via-pmu node itself, in this
331 * case we skip this function completely as the device-tree will
332 * not contain anything useful.
333 */
334 if (!strcmp(adap->dev.of_node->name, "via-pmu"))
335 return;
336
337 for_each_child_of_node(adap->dev.of_node, node) {
338 struct i2c_board_info info = {};
339 u32 addr;
340
341 /* Get address & channel */
342 addr = i2c_powermac_get_addr(adap, bus, node);
343 if (addr == 0xffffffff)
344 continue;
345
346 /* Multibus setup, check channel */
347 if (!pmac_i2c_match_adapter(node, adap))
348 continue;
349
350 dev_dbg(&adap->dev, "i2c-powermac: register %pOF\n", node);
351
352 /*
353 * Keep track of some device existence to handle
354 * workarounds later.
355 */
356 if (of_device_is_compatible(node, "pcm3052"))
357 found_onyx = true;
358
359 /* Make up a modalias */
360 if (!i2c_powermac_get_type(adap, node, addr,
361 info.type, sizeof(info.type))) {
362 continue;
363 }
364
365 /* Fill out the rest of the info structure */
366 info.addr = addr;
367 info.irq = irq_of_parse_and_map(node, 0);
368 info.of_node = of_node_get(node);
369
370 newdev = i2c_new_device(adap, &info);
371 if (!newdev) {
372 dev_err(&adap->dev, "i2c-powermac: Failure to register"
373 " %pOF\n", node);
374 of_node_put(node);
375 /* We do not dispose of the interrupt mapping on
376 * purpose. It's not necessary (interrupt cannot be
377 * re-used) and somebody else might have grabbed it
378 * via direct DT lookup so let's not bother
379 */
380 continue;
381 }
382 }
383
384 /* Additional workarounds */
385 i2c_powermac_add_missing(adap, bus, found_onyx);
386 }
387
388 static int i2c_powermac_probe(struct platform_device *dev)
389 {
390 struct pmac_i2c_bus *bus = dev_get_platdata(&dev->dev);
391 struct device_node *parent = NULL;
392 struct i2c_adapter *adapter;
393 const char *basename;
394 int rc;
395
396 if (bus == NULL)
397 return -EINVAL;
398 adapter = pmac_i2c_get_adapter(bus);
399
400 /* Ok, now we need to make up a name for the interface that will
401 * match what we used to do in the past, that is basically the
402 * controller's parent device node for keywest. PMU didn't have a
403 * naming convention and SMU has a different one
404 */
405 switch(pmac_i2c_get_type(bus)) {
406 case pmac_i2c_bus_keywest:
407 parent = of_get_parent(pmac_i2c_get_controller(bus));
408 if (parent == NULL)
409 return -EINVAL;
410 basename = parent->name;
411 break;
412 case pmac_i2c_bus_pmu:
413 basename = "pmu";
414 break;
415 case pmac_i2c_bus_smu:
416 /* This is not what we used to do but I'm fixing drivers at
417 * the same time as this change
418 */
419 basename = "smu";
420 break;
421 default:
422 return -EINVAL;
423 }
424 snprintf(adapter->name, sizeof(adapter->name), "%s %d", basename,
425 pmac_i2c_get_channel(bus));
426 of_node_put(parent);
427
428 platform_set_drvdata(dev, adapter);
429 adapter->algo = &i2c_powermac_algorithm;
430 adapter->quirks = &i2c_powermac_quirks;
431 i2c_set_adapdata(adapter, bus);
432 adapter->dev.parent = &dev->dev;
433
434 /* Clear of_node to skip automatic registration of i2c child nodes */
435 adapter->dev.of_node = NULL;
436 rc = i2c_add_adapter(adapter);
437 if (rc) {
438 printk(KERN_ERR "i2c-powermac: Adapter %s registration "
439 "failed\n", adapter->name);
440 memset(adapter, 0, sizeof(*adapter));
441 return rc;
442 }
443
444 printk(KERN_INFO "PowerMac i2c bus %s registered\n", adapter->name);
445
446 /* Use custom child registration due to Apple device-tree funkyness */
447 adapter->dev.of_node = dev->dev.of_node;
448 i2c_powermac_register_devices(adapter, bus);
449
450 return 0;
451 }
452
453 static struct platform_driver i2c_powermac_driver = {
454 .probe = i2c_powermac_probe,
455 .remove = i2c_powermac_remove,
456 .driver = {
457 .name = "i2c-powermac",
458 .bus = &platform_bus_type,
459 },
460 };
461
462 module_platform_driver(i2c_powermac_driver);
463
464 MODULE_ALIAS("platform:i2c-powermac");
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