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.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 #include <linux/module.h>
24 #include <linux/kernel.h>
25 #include <linux/types.h>
26 #include <linux/i2c.h>
27 #include <linux/init.h>
28 #include <linux/device.h>
29 #include <linux/platform_device.h>
31 #include <asm/pmac_low_i2c.h>
33 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
34 MODULE_DESCRIPTION("I2C driver for Apple PowerMac");
35 MODULE_LICENSE("GPL");
38 * SMBUS-type transfer entrypoint
40 static s32
i2c_powermac_smbus_xfer( struct i2c_adapter
* adap
,
46 union i2c_smbus_data
* data
)
48 struct pmac_i2c_bus
*bus
= i2c_get_adapdata(adap
);
50 int read
= (read_write
== I2C_SMBUS_READ
);
51 int addrdir
= (addr
<< 1) | read
;
52 int mode
, subsize
, len
;
57 if (size
== I2C_SMBUS_QUICK
|| size
== I2C_SMBUS_BYTE
) {
58 mode
= pmac_i2c_mode_std
;
62 mode
= read
? pmac_i2c_mode_combined
: pmac_i2c_mode_stdsub
;
73 case I2C_SMBUS_BYTE_DATA
:
77 case I2C_SMBUS_WORD_DATA
:
79 local
[0] = data
->word
& 0xff;
80 local
[1] = (data
->word
>> 8) & 0xff;
86 /* Note that these are broken vs. the expected smbus API where
87 * on reads, the length is actually returned from the function,
88 * but I think the current API makes no sense and I don't want
89 * any driver that I haven't verified for correctness to go
90 * anywhere near a pmac i2c bus anyway ...
92 * I'm also not completely sure what kind of phases to do between
93 * the actual command and the data (what I am _supposed_ to do that
94 * is). For now, I assume writes are a single stream and reads have
95 * a repeat start/addr phase (but not stop in between)
97 case I2C_SMBUS_BLOCK_DATA
:
99 len
= data
->block
[0] + 1;
101 case I2C_SMBUS_I2C_BLOCK_DATA
:
102 buf
= &data
->block
[1];
103 len
= data
->block
[0];
110 rc
= pmac_i2c_open(bus
, 0);
112 dev_err(&adap
->dev
, "Failed to open I2C, err %d\n", rc
);
116 rc
= pmac_i2c_setmode(bus
, mode
);
118 dev_err(&adap
->dev
, "Failed to set I2C mode %d, err %d\n",
123 rc
= pmac_i2c_xfer(bus
, addrdir
, subsize
, subaddr
, buf
, len
);
127 "I2C transfer at 0x%02x failed, size %d, "
128 "err %d\n", addrdir
>> 1, size
, rc
);
131 "I2C transfer at 0x%02x failed, size %d, "
132 "err %d\n", addrdir
>> 1, size
, rc
);
136 if (size
== I2C_SMBUS_WORD_DATA
&& read
) {
137 data
->word
= ((u16
)local
[1]) << 8;
138 data
->word
|= local
[0];
147 * Generic i2c master transfer entrypoint. This driver only support single
148 * messages (for "lame i2c" transfers). Anything else should use the smbus
151 static int i2c_powermac_master_xfer( struct i2c_adapter
*adap
,
152 struct i2c_msg
*msgs
,
155 struct pmac_i2c_bus
*bus
= i2c_get_adapdata(adap
);
162 "Multi-message I2C transactions not supported\n");
166 if (msgs
->flags
& I2C_M_TEN
)
168 read
= (msgs
->flags
& I2C_M_RD
) != 0;
169 addrdir
= (msgs
->addr
<< 1) | read
;
171 rc
= pmac_i2c_open(bus
, 0);
173 dev_err(&adap
->dev
, "Failed to open I2C, err %d\n", rc
);
176 rc
= pmac_i2c_setmode(bus
, pmac_i2c_mode_std
);
178 dev_err(&adap
->dev
, "Failed to set I2C mode %d, err %d\n",
179 pmac_i2c_mode_std
, rc
);
182 rc
= pmac_i2c_xfer(bus
, addrdir
, 0, 0, msgs
->buf
, msgs
->len
);
185 dev_dbg(&adap
->dev
, "I2C %s 0x%02x failed, err %d\n",
186 addrdir
& 1 ? "read from" : "write to",
189 dev_err(&adap
->dev
, "I2C %s 0x%02x failed, err %d\n",
190 addrdir
& 1 ? "read from" : "write to",
195 return rc
< 0 ? rc
: 1;
198 static u32
i2c_powermac_func(struct i2c_adapter
* adapter
)
200 return I2C_FUNC_SMBUS_QUICK
| I2C_FUNC_SMBUS_BYTE
|
201 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
|
202 I2C_FUNC_SMBUS_BLOCK_DATA
| I2C_FUNC_I2C
;
205 /* For now, we only handle smbus */
206 static const struct i2c_algorithm i2c_powermac_algorithm
= {
207 .smbus_xfer
= i2c_powermac_smbus_xfer
,
208 .master_xfer
= i2c_powermac_master_xfer
,
209 .functionality
= i2c_powermac_func
,
213 static int i2c_powermac_remove(struct platform_device
*dev
)
215 struct i2c_adapter
*adapter
= platform_get_drvdata(dev
);
218 rc
= i2c_del_adapter(adapter
);
219 /* We aren't that prepared to deal with this... */
222 "i2c-powermac.c: Failed to remove bus %s !\n",
224 memset(adapter
, 0, sizeof(*adapter
));
229 static u32
i2c_powermac_get_addr(struct i2c_adapter
*adap
,
230 struct pmac_i2c_bus
*bus
,
231 struct device_node
*node
)
236 /* First check for valid "reg" */
237 prop
= of_get_property(node
, "reg", &len
);
238 if (prop
&& (len
>= sizeof(int)))
239 return (be32_to_cpup(prop
) & 0xff) >> 1;
241 /* Then check old-style "i2c-address" */
242 prop
= of_get_property(node
, "i2c-address", &len
);
243 if (prop
&& (len
>= sizeof(int)))
244 return (be32_to_cpup(prop
) & 0xff) >> 1;
246 /* Now handle some devices with missing "reg" properties */
247 if (!strcmp(node
->name
, "cereal"))
249 else if (!strcmp(node
->name
, "deq"))
252 dev_warn(&adap
->dev
, "No i2c address for %s\n", node
->full_name
);
257 static void i2c_powermac_create_one(struct i2c_adapter
*adap
,
261 struct i2c_board_info info
= {};
262 struct i2c_client
*newdev
;
264 strncpy(info
.type
, type
, sizeof(info
.type
));
266 newdev
= i2c_new_device(adap
, &info
);
269 "i2c-powermac: Failure to register missing %s\n",
273 static void i2c_powermac_add_missing(struct i2c_adapter
*adap
,
274 struct pmac_i2c_bus
*bus
,
277 struct device_node
*busnode
= pmac_i2c_get_bus_node(bus
);
280 /* Check for the onyx audio codec */
281 #define ONYX_REG_CONTROL 67
282 if (of_device_is_compatible(busnode
, "k2-i2c") && !found_onyx
) {
283 union i2c_smbus_data data
;
285 rc
= i2c_smbus_xfer(adap
, 0x46, 0, I2C_SMBUS_READ
,
286 ONYX_REG_CONTROL
, I2C_SMBUS_BYTE_DATA
,
289 i2c_powermac_create_one(adap
, "MAC,pcm3052", 0x46);
291 rc
= i2c_smbus_xfer(adap
, 0x47, 0, I2C_SMBUS_READ
,
292 ONYX_REG_CONTROL
, I2C_SMBUS_BYTE_DATA
,
295 i2c_powermac_create_one(adap
, "MAC,pcm3052", 0x47);
299 static bool i2c_powermac_get_type(struct i2c_adapter
*adap
,
300 struct device_node
*node
,
301 u32 addr
, char *type
, int type_size
)
305 /* Note: we to _NOT_ want the standard
306 * i2c drivers to match with any of our powermac stuff
307 * unless they have been specifically modified to handle
308 * it on a case by case basis. For example, for thermal
309 * control, things like lm75 etc... shall match with their
310 * corresponding windfarm drivers, _NOT_ the generic ones,
311 * so we force a prefix of AAPL, onto the modalias to
315 /* First try proper modalias */
316 if (of_modalias_node(node
, tmp
, sizeof(tmp
)) >= 0) {
317 snprintf(type
, type_size
, "MAC,%s", tmp
);
321 /* Now look for known workarounds */
322 if (!strcmp(node
->name
, "deq")) {
323 /* Apple uses address 0x34 for TAS3001 and 0x35 for TAS3004 */
325 snprintf(type
, type_size
, "MAC,tas3001");
327 } else if (addr
== 0x35) {
328 snprintf(type
, type_size
, "MAC,tas3004");
333 dev_err(&adap
->dev
, "i2c-powermac: modalias failure"
334 " on %s\n", node
->full_name
);
338 static void i2c_powermac_register_devices(struct i2c_adapter
*adap
,
339 struct pmac_i2c_bus
*bus
)
341 struct i2c_client
*newdev
;
342 struct device_node
*node
;
346 * In some cases we end up with the via-pmu node itself, in this
347 * case we skip this function completely as the device-tree will
348 * not contain anything useful.
350 if (!strcmp(adap
->dev
.of_node
->name
, "via-pmu"))
353 for_each_child_of_node(adap
->dev
.of_node
, node
) {
354 struct i2c_board_info info
= {};
357 /* Get address & channel */
358 addr
= i2c_powermac_get_addr(adap
, bus
, node
);
359 if (addr
== 0xffffffff)
362 /* Multibus setup, check channel */
363 if (!pmac_i2c_match_adapter(node
, adap
))
366 dev_dbg(&adap
->dev
, "i2c-powermac: register %s\n",
370 * Keep track of some device existence to handle
373 if (of_device_is_compatible(node
, "pcm3052"))
376 /* Make up a modalias */
377 if (!i2c_powermac_get_type(adap
, node
, addr
,
378 info
.type
, sizeof(info
.type
))) {
382 /* Fill out the rest of the info structure */
384 info
.irq
= irq_of_parse_and_map(node
, 0);
385 info
.of_node
= of_node_get(node
);
387 newdev
= i2c_new_device(adap
, &info
);
389 dev_err(&adap
->dev
, "i2c-powermac: Failure to register"
390 " %s\n", node
->full_name
);
392 /* We do not dispose of the interrupt mapping on
393 * purpose. It's not necessary (interrupt cannot be
394 * re-used) and somebody else might have grabbed it
395 * via direct DT lookup so let's not bother
401 /* Additional workarounds */
402 i2c_powermac_add_missing(adap
, bus
, found_onyx
);
405 static int i2c_powermac_probe(struct platform_device
*dev
)
407 struct pmac_i2c_bus
*bus
= dev
->dev
.platform_data
;
408 struct device_node
*parent
= NULL
;
409 struct i2c_adapter
*adapter
;
410 const char *basename
;
415 adapter
= pmac_i2c_get_adapter(bus
);
417 /* Ok, now we need to make up a name for the interface that will
418 * match what we used to do in the past, that is basically the
419 * controller's parent device node for keywest. PMU didn't have a
420 * naming convention and SMU has a different one
422 switch(pmac_i2c_get_type(bus
)) {
423 case pmac_i2c_bus_keywest
:
424 parent
= of_get_parent(pmac_i2c_get_controller(bus
));
427 basename
= parent
->name
;
429 case pmac_i2c_bus_pmu
:
432 case pmac_i2c_bus_smu
:
433 /* This is not what we used to do but I'm fixing drivers at
434 * the same time as this change
441 snprintf(adapter
->name
, sizeof(adapter
->name
), "%s %d", basename
,
442 pmac_i2c_get_channel(bus
));
445 platform_set_drvdata(dev
, adapter
);
446 adapter
->algo
= &i2c_powermac_algorithm
;
447 i2c_set_adapdata(adapter
, bus
);
448 adapter
->dev
.parent
= &dev
->dev
;
449 adapter
->dev
.of_node
= dev
->dev
.of_node
;
450 rc
= i2c_add_adapter(adapter
);
452 printk(KERN_ERR
"i2c-powermac: Adapter %s registration "
453 "failed\n", adapter
->name
);
454 memset(adapter
, 0, sizeof(*adapter
));
457 printk(KERN_INFO
"PowerMac i2c bus %s registered\n", adapter
->name
);
459 /* Cannot use of_i2c_register_devices() due to Apple device-tree
462 i2c_powermac_register_devices(adapter
, bus
);
467 static struct platform_driver i2c_powermac_driver
= {
468 .probe
= i2c_powermac_probe
,
469 .remove
= i2c_powermac_remove
,
471 .name
= "i2c-powermac",
472 .bus
= &platform_bus_type
,
476 module_platform_driver(i2c_powermac_driver
);
478 MODULE_ALIAS("platform:i2c-powermac");