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
);
126 "I2C transfer at 0x%02x failed, size %d, err %d\n",
127 addrdir
>> 1, size
, rc
);
131 if (size
== I2C_SMBUS_WORD_DATA
&& read
) {
132 data
->word
= ((u16
)local
[1]) << 8;
133 data
->word
|= local
[0];
142 * Generic i2c master transfer entrypoint. This driver only support single
143 * messages (for "lame i2c" transfers). Anything else should use the smbus
146 static int i2c_powermac_master_xfer( struct i2c_adapter
*adap
,
147 struct i2c_msg
*msgs
,
150 struct pmac_i2c_bus
*bus
= i2c_get_adapdata(adap
);
157 "Multi-message I2C transactions not supported\n");
161 if (msgs
->flags
& I2C_M_TEN
)
163 read
= (msgs
->flags
& I2C_M_RD
) != 0;
164 addrdir
= (msgs
->addr
<< 1) | read
;
166 rc
= pmac_i2c_open(bus
, 0);
168 dev_err(&adap
->dev
, "Failed to open I2C, err %d\n", rc
);
171 rc
= pmac_i2c_setmode(bus
, pmac_i2c_mode_std
);
173 dev_err(&adap
->dev
, "Failed to set I2C mode %d, err %d\n",
174 pmac_i2c_mode_std
, rc
);
177 rc
= pmac_i2c_xfer(bus
, addrdir
, 0, 0, msgs
->buf
, msgs
->len
);
179 dev_err(&adap
->dev
, "I2C %s 0x%02x failed, err %d\n",
180 addrdir
& 1 ? "read from" : "write to", addrdir
>> 1,
184 return rc
< 0 ? rc
: 1;
187 static u32
i2c_powermac_func(struct i2c_adapter
* adapter
)
189 return I2C_FUNC_SMBUS_QUICK
| I2C_FUNC_SMBUS_BYTE
|
190 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
|
191 I2C_FUNC_SMBUS_BLOCK_DATA
| I2C_FUNC_I2C
;
194 /* For now, we only handle smbus */
195 static const struct i2c_algorithm i2c_powermac_algorithm
= {
196 .smbus_xfer
= i2c_powermac_smbus_xfer
,
197 .master_xfer
= i2c_powermac_master_xfer
,
198 .functionality
= i2c_powermac_func
,
202 static int __devexit
i2c_powermac_remove(struct platform_device
*dev
)
204 struct i2c_adapter
*adapter
= platform_get_drvdata(dev
);
207 rc
= i2c_del_adapter(adapter
);
208 /* We aren't that prepared to deal with this... */
211 "i2c-powermac.c: Failed to remove bus %s !\n",
213 platform_set_drvdata(dev
, NULL
);
214 memset(adapter
, 0, sizeof(*adapter
));
220 static int __devinit
i2c_powermac_probe(struct platform_device
*dev
)
222 struct pmac_i2c_bus
*bus
= dev
->dev
.platform_data
;
223 struct device_node
*parent
= NULL
;
224 struct i2c_adapter
*adapter
;
225 const char *basename
;
230 adapter
= pmac_i2c_get_adapter(bus
);
232 /* Ok, now we need to make up a name for the interface that will
233 * match what we used to do in the past, that is basically the
234 * controller's parent device node for keywest. PMU didn't have a
235 * naming convention and SMU has a different one
237 switch(pmac_i2c_get_type(bus
)) {
238 case pmac_i2c_bus_keywest
:
239 parent
= of_get_parent(pmac_i2c_get_controller(bus
));
242 basename
= parent
->name
;
244 case pmac_i2c_bus_pmu
:
247 case pmac_i2c_bus_smu
:
248 /* This is not what we used to do but I'm fixing drivers at
249 * the same time as this change
256 snprintf(adapter
->name
, sizeof(adapter
->name
), "%s %d", basename
,
257 pmac_i2c_get_channel(bus
));
260 platform_set_drvdata(dev
, adapter
);
261 adapter
->algo
= &i2c_powermac_algorithm
;
262 i2c_set_adapdata(adapter
, bus
);
263 adapter
->dev
.parent
= &dev
->dev
;
264 rc
= i2c_add_adapter(adapter
);
266 printk(KERN_ERR
"i2c-powermac: Adapter %s registration "
267 "failed\n", adapter
->name
);
268 memset(adapter
, 0, sizeof(*adapter
));
271 printk(KERN_INFO
"PowerMac i2c bus %s registered\n", adapter
->name
);
273 if (!strncmp(basename
, "uni-n", 5)) {
274 struct device_node
*np
;
276 struct i2c_board_info info
;
278 /* Instantiate I2C motion sensor if present */
279 np
= of_find_node_by_name(NULL
, "accelerometer");
280 if (np
&& of_device_is_compatible(np
, "AAPL,accelerometer_1") &&
281 (prop
= of_get_property(np
, "reg", NULL
))) {
285 /* look for bus either using "reg" or by path */
286 tmp_bus
= strstr(np
->full_name
, "/i2c-bus@");
288 i2c_bus
= *(tmp_bus
+ 9) - '0';
290 i2c_bus
= ((*prop
) >> 8) & 0x0f;
292 if (pmac_i2c_get_channel(bus
) == i2c_bus
) {
293 memset(&info
, 0, sizeof(struct i2c_board_info
));
294 info
.addr
= ((*prop
) & 0xff) >> 1;
295 strlcpy(info
.type
, "ams", I2C_NAME_SIZE
);
296 i2c_new_device(adapter
, &info
);
305 /* work with hotplug and coldplug */
306 MODULE_ALIAS("platform:i2c-powermac");
308 static struct platform_driver i2c_powermac_driver
= {
309 .probe
= i2c_powermac_probe
,
310 .remove
= __devexit_p(i2c_powermac_remove
),
312 .name
= "i2c-powermac",
313 .bus
= &platform_bus_type
,
317 static int __init
i2c_powermac_init(void)
319 platform_driver_register(&i2c_powermac_driver
);
324 static void __exit
i2c_powermac_cleanup(void)
326 platform_driver_unregister(&i2c_powermac_driver
);
329 module_init(i2c_powermac_init
);
330 module_exit(i2c_powermac_cleanup
);