2 i2c Support for Apple SMU Controller
4 Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp.
5 <benh@kernel.crashing.org>
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.
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.
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>
27 #include <asm/pmac_low_i2c.h>
29 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
30 MODULE_DESCRIPTION("I2C driver for Apple PowerMac");
31 MODULE_LICENSE("GPL");
34 * SMBUS-type transfer entrypoint
36 static s32
i2c_powermac_smbus_xfer( struct i2c_adapter
* adap
,
42 union i2c_smbus_data
* data
)
44 struct pmac_i2c_bus
*bus
= i2c_get_adapdata(adap
);
46 int read
= (read_write
== I2C_SMBUS_READ
);
47 int addrdir
= (addr
<< 1) | read
;
48 int mode
, subsize
, len
;
53 if (size
== I2C_SMBUS_QUICK
|| size
== I2C_SMBUS_BYTE
) {
54 mode
= pmac_i2c_mode_std
;
58 mode
= read
? pmac_i2c_mode_combined
: pmac_i2c_mode_stdsub
;
69 case I2C_SMBUS_BYTE_DATA
:
73 case I2C_SMBUS_WORD_DATA
:
75 local
[0] = data
->word
& 0xff;
76 local
[1] = (data
->word
>> 8) & 0xff;
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 ...
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)
93 case I2C_SMBUS_BLOCK_DATA
:
95 len
= data
->block
[0] + 1;
97 case I2C_SMBUS_I2C_BLOCK_DATA
:
98 buf
= &data
->block
[1];
106 rc
= pmac_i2c_open(bus
, 0);
108 dev_err(&adap
->dev
, "Failed to open I2C, err %d\n", rc
);
112 rc
= pmac_i2c_setmode(bus
, mode
);
114 dev_err(&adap
->dev
, "Failed to set I2C mode %d, err %d\n",
119 rc
= pmac_i2c_xfer(bus
, addrdir
, subsize
, subaddr
, buf
, len
);
123 "I2C transfer at 0x%02x failed, size %d, "
124 "err %d\n", addrdir
>> 1, size
, rc
);
127 "I2C transfer at 0x%02x failed, size %d, "
128 "err %d\n", addrdir
>> 1, size
, rc
);
132 if (size
== I2C_SMBUS_WORD_DATA
&& read
) {
133 data
->word
= ((u16
)local
[1]) << 8;
134 data
->word
|= local
[0];
143 * Generic i2c master transfer entrypoint. This driver only support single
144 * messages (for "lame i2c" transfers). Anything else should use the smbus
147 static int i2c_powermac_master_xfer( struct i2c_adapter
*adap
,
148 struct i2c_msg
*msgs
,
151 struct pmac_i2c_bus
*bus
= i2c_get_adapdata(adap
);
158 "Multi-message I2C transactions not supported\n");
162 if (msgs
->flags
& I2C_M_TEN
)
164 read
= (msgs
->flags
& I2C_M_RD
) != 0;
165 addrdir
= (msgs
->addr
<< 1) | read
;
167 rc
= pmac_i2c_open(bus
, 0);
169 dev_err(&adap
->dev
, "Failed to open I2C, err %d\n", rc
);
172 rc
= pmac_i2c_setmode(bus
, pmac_i2c_mode_std
);
174 dev_err(&adap
->dev
, "Failed to set I2C mode %d, err %d\n",
175 pmac_i2c_mode_std
, rc
);
178 rc
= pmac_i2c_xfer(bus
, addrdir
, 0, 0, msgs
->buf
, msgs
->len
);
181 dev_dbg(&adap
->dev
, "I2C %s 0x%02x failed, err %d\n",
182 addrdir
& 1 ? "read from" : "write to",
185 dev_err(&adap
->dev
, "I2C %s 0x%02x failed, err %d\n",
186 addrdir
& 1 ? "read from" : "write to",
191 return rc
< 0 ? rc
: 1;
194 static u32
i2c_powermac_func(struct i2c_adapter
* adapter
)
196 return I2C_FUNC_SMBUS_QUICK
| I2C_FUNC_SMBUS_BYTE
|
197 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
|
198 I2C_FUNC_SMBUS_BLOCK_DATA
| I2C_FUNC_I2C
;
201 /* For now, we only handle smbus */
202 static const struct i2c_algorithm i2c_powermac_algorithm
= {
203 .smbus_xfer
= i2c_powermac_smbus_xfer
,
204 .master_xfer
= i2c_powermac_master_xfer
,
205 .functionality
= i2c_powermac_func
,
209 static int i2c_powermac_remove(struct platform_device
*dev
)
211 struct i2c_adapter
*adapter
= platform_get_drvdata(dev
);
213 i2c_del_adapter(adapter
);
214 memset(adapter
, 0, sizeof(*adapter
));
219 static u32
i2c_powermac_get_addr(struct i2c_adapter
*adap
,
220 struct pmac_i2c_bus
*bus
,
221 struct device_node
*node
)
226 /* First check for valid "reg" */
227 prop
= of_get_property(node
, "reg", &len
);
228 if (prop
&& (len
>= sizeof(int)))
229 return (be32_to_cpup(prop
) & 0xff) >> 1;
231 /* Then check old-style "i2c-address" */
232 prop
= of_get_property(node
, "i2c-address", &len
);
233 if (prop
&& (len
>= sizeof(int)))
234 return (be32_to_cpup(prop
) & 0xff) >> 1;
236 /* Now handle some devices with missing "reg" properties */
237 if (!strcmp(node
->name
, "cereal"))
239 else if (!strcmp(node
->name
, "deq"))
242 dev_warn(&adap
->dev
, "No i2c address for %s\n", node
->full_name
);
247 static void i2c_powermac_create_one(struct i2c_adapter
*adap
,
251 struct i2c_board_info info
= {};
252 struct i2c_client
*newdev
;
254 strncpy(info
.type
, type
, sizeof(info
.type
));
256 newdev
= i2c_new_device(adap
, &info
);
259 "i2c-powermac: Failure to register missing %s\n",
263 static void i2c_powermac_add_missing(struct i2c_adapter
*adap
,
264 struct pmac_i2c_bus
*bus
,
267 struct device_node
*busnode
= pmac_i2c_get_bus_node(bus
);
270 /* Check for the onyx audio codec */
271 #define ONYX_REG_CONTROL 67
272 if (of_device_is_compatible(busnode
, "k2-i2c") && !found_onyx
) {
273 union i2c_smbus_data data
;
275 rc
= i2c_smbus_xfer(adap
, 0x46, 0, I2C_SMBUS_READ
,
276 ONYX_REG_CONTROL
, I2C_SMBUS_BYTE_DATA
,
279 i2c_powermac_create_one(adap
, "MAC,pcm3052", 0x46);
281 rc
= i2c_smbus_xfer(adap
, 0x47, 0, I2C_SMBUS_READ
,
282 ONYX_REG_CONTROL
, I2C_SMBUS_BYTE_DATA
,
285 i2c_powermac_create_one(adap
, "MAC,pcm3052", 0x47);
289 static bool i2c_powermac_get_type(struct i2c_adapter
*adap
,
290 struct device_node
*node
,
291 u32 addr
, char *type
, int type_size
)
295 /* Note: we to _NOT_ want the standard
296 * i2c drivers to match with any of our powermac stuff
297 * unless they have been specifically modified to handle
298 * it on a case by case basis. For example, for thermal
299 * control, things like lm75 etc... shall match with their
300 * corresponding windfarm drivers, _NOT_ the generic ones,
301 * so we force a prefix of AAPL, onto the modalias to
305 /* First try proper modalias */
306 if (of_modalias_node(node
, tmp
, sizeof(tmp
)) >= 0) {
307 snprintf(type
, type_size
, "MAC,%s", tmp
);
311 /* Now look for known workarounds */
312 if (!strcmp(node
->name
, "deq")) {
313 /* Apple uses address 0x34 for TAS3001 and 0x35 for TAS3004 */
315 snprintf(type
, type_size
, "MAC,tas3001");
317 } else if (addr
== 0x35) {
318 snprintf(type
, type_size
, "MAC,tas3004");
323 dev_err(&adap
->dev
, "i2c-powermac: modalias failure"
324 " on %s\n", node
->full_name
);
328 static void i2c_powermac_register_devices(struct i2c_adapter
*adap
,
329 struct pmac_i2c_bus
*bus
)
331 struct i2c_client
*newdev
;
332 struct device_node
*node
;
336 * In some cases we end up with the via-pmu node itself, in this
337 * case we skip this function completely as the device-tree will
338 * not contain anything useful.
340 if (!strcmp(adap
->dev
.of_node
->name
, "via-pmu"))
343 for_each_child_of_node(adap
->dev
.of_node
, node
) {
344 struct i2c_board_info info
= {};
347 /* Get address & channel */
348 addr
= i2c_powermac_get_addr(adap
, bus
, node
);
349 if (addr
== 0xffffffff)
352 /* Multibus setup, check channel */
353 if (!pmac_i2c_match_adapter(node
, adap
))
356 dev_dbg(&adap
->dev
, "i2c-powermac: register %s\n",
360 * Keep track of some device existence to handle
363 if (of_device_is_compatible(node
, "pcm3052"))
366 /* Make up a modalias */
367 if (!i2c_powermac_get_type(adap
, node
, addr
,
368 info
.type
, sizeof(info
.type
))) {
372 /* Fill out the rest of the info structure */
374 info
.irq
= irq_of_parse_and_map(node
, 0);
375 info
.of_node
= of_node_get(node
);
377 newdev
= i2c_new_device(adap
, &info
);
379 dev_err(&adap
->dev
, "i2c-powermac: Failure to register"
380 " %s\n", node
->full_name
);
382 /* We do not dispose of the interrupt mapping on
383 * purpose. It's not necessary (interrupt cannot be
384 * re-used) and somebody else might have grabbed it
385 * via direct DT lookup so let's not bother
391 /* Additional workarounds */
392 i2c_powermac_add_missing(adap
, bus
, found_onyx
);
395 static int i2c_powermac_probe(struct platform_device
*dev
)
397 struct pmac_i2c_bus
*bus
= dev_get_platdata(&dev
->dev
);
398 struct device_node
*parent
= NULL
;
399 struct i2c_adapter
*adapter
;
400 const char *basename
;
405 adapter
= pmac_i2c_get_adapter(bus
);
407 /* Ok, now we need to make up a name for the interface that will
408 * match what we used to do in the past, that is basically the
409 * controller's parent device node for keywest. PMU didn't have a
410 * naming convention and SMU has a different one
412 switch(pmac_i2c_get_type(bus
)) {
413 case pmac_i2c_bus_keywest
:
414 parent
= of_get_parent(pmac_i2c_get_controller(bus
));
417 basename
= parent
->name
;
419 case pmac_i2c_bus_pmu
:
422 case pmac_i2c_bus_smu
:
423 /* This is not what we used to do but I'm fixing drivers at
424 * the same time as this change
431 snprintf(adapter
->name
, sizeof(adapter
->name
), "%s %d", basename
,
432 pmac_i2c_get_channel(bus
));
435 platform_set_drvdata(dev
, adapter
);
436 adapter
->algo
= &i2c_powermac_algorithm
;
437 i2c_set_adapdata(adapter
, bus
);
438 adapter
->dev
.parent
= &dev
->dev
;
440 /* Clear of_node to skip automatic registration of i2c child nodes */
441 adapter
->dev
.of_node
= NULL
;
442 rc
= i2c_add_adapter(adapter
);
444 printk(KERN_ERR
"i2c-powermac: Adapter %s registration "
445 "failed\n", adapter
->name
);
446 memset(adapter
, 0, sizeof(*adapter
));
450 printk(KERN_INFO
"PowerMac i2c bus %s registered\n", adapter
->name
);
452 /* Use custom child registration due to Apple device-tree funkyness */
453 adapter
->dev
.of_node
= dev
->dev
.of_node
;
454 i2c_powermac_register_devices(adapter
, bus
);
459 static struct platform_driver i2c_powermac_driver
= {
460 .probe
= i2c_powermac_probe
,
461 .remove
= i2c_powermac_remove
,
463 .name
= "i2c-powermac",
464 .bus
= &platform_bus_type
,
468 module_platform_driver(i2c_powermac_driver
);
470 MODULE_ALIAS("platform:i2c-powermac");