[PATCH] i2c-i801: Remove PCI function check
[linux-2.6] / drivers / i2c / busses / i2c-powermac.c
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     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.
20
21 */
22
23 #include <linux/config.h>
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/types.h>
27 #include <linux/i2c.h>
28 #include <linux/init.h>
29 #include <linux/completion.h>
30 #include <linux/device.h>
31 #include <linux/platform_device.h>
32 #include <asm/prom.h>
33 #include <asm/pmac_low_i2c.h>
34
35 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
36 MODULE_DESCRIPTION("I2C driver for Apple PowerMac");
37 MODULE_LICENSE("GPL");
38
39 /*
40  * SMBUS-type transfer entrypoint
41  */
42 static s32 i2c_powermac_smbus_xfer(     struct i2c_adapter*     adap,
43                                         u16                     addr,
44                                         unsigned short          flags,
45                                         char                    read_write,
46                                         u8                      command,
47                                         int                     size,
48                                         union i2c_smbus_data*   data)
49 {
50         struct pmac_i2c_bus     *bus = i2c_get_adapdata(adap);
51         int                     rc = 0;
52         int                     read = (read_write == I2C_SMBUS_READ);
53         int                     addrdir = (addr << 1) | read;
54         u8                      local[2];
55
56         rc = pmac_i2c_open(bus, 0);
57         if (rc)
58                 return rc;
59
60         switch (size) {
61         case I2C_SMBUS_QUICK:
62                 rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std);
63                 if (rc)
64                         goto bail;
65                 rc = pmac_i2c_xfer(bus, addrdir, 0, 0, NULL, 0);
66                 break;
67         case I2C_SMBUS_BYTE:
68                 rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std);
69                 if (rc)
70                         goto bail;
71                 rc = pmac_i2c_xfer(bus, addrdir, 0, 0, &data->byte, 1);
72                 break;
73         case I2C_SMBUS_BYTE_DATA:
74                 rc = pmac_i2c_setmode(bus, read ?
75                                       pmac_i2c_mode_combined :
76                                       pmac_i2c_mode_stdsub);
77                 if (rc)
78                         goto bail;
79                 rc = pmac_i2c_xfer(bus, addrdir, 1, command, &data->byte, 1);
80                 break;
81         case I2C_SMBUS_WORD_DATA:
82                 rc = pmac_i2c_setmode(bus, read ?
83                                       pmac_i2c_mode_combined :
84                                       pmac_i2c_mode_stdsub);
85                 if (rc)
86                         goto bail;
87                 if (!read) {
88                         local[0] = data->word & 0xff;
89                         local[1] = (data->word >> 8) & 0xff;
90                 }
91                 rc = pmac_i2c_xfer(bus, addrdir, 1, command, local, 2);
92                 if (rc == 0 && read) {
93                         data->word = ((u16)local[1]) << 8;
94                         data->word |= local[0];
95                 }
96                 break;
97
98         /* Note that these are broken vs. the expected smbus API where
99          * on reads, the lenght is actually returned from the function,
100          * but I think the current API makes no sense and I don't want
101          * any driver that I haven't verified for correctness to go
102          * anywhere near a pmac i2c bus anyway ...
103          *
104          * I'm also not completely sure what kind of phases to do between
105          * the actual command and the data (what I am _supposed_ to do that
106          * is). For now, I assume writes are a single stream and reads have
107          * a repeat start/addr phase (but not stop in between)
108          */
109         case I2C_SMBUS_BLOCK_DATA:
110                 rc = pmac_i2c_setmode(bus, read ?
111                                       pmac_i2c_mode_combined :
112                                       pmac_i2c_mode_stdsub);
113                 if (rc)
114                         goto bail;
115                 rc = pmac_i2c_xfer(bus, addrdir, 1, command, data->block,
116                                    data->block[0] + 1);
117
118                 break;
119         case I2C_SMBUS_I2C_BLOCK_DATA:
120                 rc = pmac_i2c_setmode(bus, read ?
121                                       pmac_i2c_mode_combined :
122                                       pmac_i2c_mode_stdsub);
123                 if (rc)
124                         goto bail;
125                 rc = pmac_i2c_xfer(bus, addrdir, 1, command,
126                                    read ? data->block : &data->block[1],
127                                    data->block[0]);
128                 break;
129
130         default:
131                 rc = -EINVAL;
132         }
133  bail:
134         pmac_i2c_close(bus);
135         return rc;
136 }
137
138 /*
139  * Generic i2c master transfer entrypoint. This driver only support single
140  * messages (for "lame i2c" transfers). Anything else should use the smbus
141  * entry point
142  */
143 static int i2c_powermac_master_xfer(    struct i2c_adapter *adap,
144                                         struct i2c_msg *msgs,
145                                         int num)
146 {
147         struct pmac_i2c_bus     *bus = i2c_get_adapdata(adap);
148         int                     rc = 0;
149         int                     read;
150         int                     addrdir;
151
152         if (num != 1)
153                 return -EINVAL;
154         if (msgs->flags & I2C_M_TEN)
155                 return -EINVAL;
156         read = (msgs->flags & I2C_M_RD) != 0;
157         addrdir = (msgs->addr << 1) | read;
158         if (msgs->flags & I2C_M_REV_DIR_ADDR)
159                 addrdir ^= 1;
160
161         rc = pmac_i2c_open(bus, 0);
162         if (rc)
163                 return rc;
164         rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std);
165         if (rc)
166                 goto bail;
167         rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len);
168  bail:
169         pmac_i2c_close(bus);
170         return rc < 0 ? rc : msgs->len;
171 }
172
173 static u32 i2c_powermac_func(struct i2c_adapter * adapter)
174 {
175         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
176                 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
177                 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_I2C;
178 }
179
180 /* For now, we only handle smbus */
181 static struct i2c_algorithm i2c_powermac_algorithm = {
182         .smbus_xfer     = i2c_powermac_smbus_xfer,
183         .master_xfer    = i2c_powermac_master_xfer,
184         .functionality  = i2c_powermac_func,
185 };
186
187
188 static int i2c_powermac_remove(struct device *dev)
189 {
190         struct i2c_adapter      *adapter = dev_get_drvdata(dev);
191         struct pmac_i2c_bus     *bus = i2c_get_adapdata(adapter);
192         int                     rc;
193
194         rc = i2c_del_adapter(adapter);
195         pmac_i2c_detach_adapter(bus, adapter);
196         i2c_set_adapdata(adapter, NULL);
197         /* We aren't that prepared to deal with this... */
198         if (rc)
199                 printk("i2c-powermac.c: Failed to remove bus %s !\n",
200                        adapter->name);
201         dev_set_drvdata(dev, NULL);
202         kfree(adapter);
203
204         return 0;
205 }
206
207
208 static int i2c_powermac_probe(struct device *dev)
209 {
210         struct pmac_i2c_bus *bus = dev->platform_data;
211         struct device_node *parent = NULL;
212         struct i2c_adapter *adapter;
213         char name[32], *basename;
214         int rc;
215
216         if (bus == NULL)
217                 return -EINVAL;
218
219         /* Ok, now we need to make up a name for the interface that will
220          * match what we used to do in the past, that is basically the
221          * controller's parent device node for keywest. PMU didn't have a
222          * naming convention and SMU has a different one
223          */
224         switch(pmac_i2c_get_type(bus)) {
225         case pmac_i2c_bus_keywest:
226                 parent = of_get_parent(pmac_i2c_get_controller(bus));
227                 if (parent == NULL)
228                         return -EINVAL;
229                 basename = parent->name;
230                 break;
231         case pmac_i2c_bus_pmu:
232                 basename = "pmu";
233                 break;
234         case pmac_i2c_bus_smu:
235                 /* This is not what we used to do but I'm fixing drivers at
236                  * the same time as this change
237                  */
238                 basename = "smu";
239                 break;
240         default:
241                 return -EINVAL;
242         }
243         snprintf(name, 32, "%s %d", basename, pmac_i2c_get_channel(bus));
244         of_node_put(parent);
245
246         adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
247         if (adapter == NULL) {
248                 printk(KERN_ERR "i2c-powermac: can't allocate inteface !\n");
249                 return -ENOMEM;
250         }
251         dev_set_drvdata(dev, adapter);
252         strcpy(adapter->name, name);
253         adapter->algo = &i2c_powermac_algorithm;
254         i2c_set_adapdata(adapter, bus);
255         adapter->dev.parent = dev;
256         pmac_i2c_attach_adapter(bus, adapter);
257         rc = i2c_add_adapter(adapter);
258         if (rc) {
259                 printk(KERN_ERR "i2c-powermac: Adapter %s registration "
260                        "failed\n", name);
261                 i2c_set_adapdata(adapter, NULL);
262                 pmac_i2c_detach_adapter(bus, adapter);
263         }
264
265         printk(KERN_INFO "PowerMac i2c bus %s registered\n", name);
266         return rc;
267 }
268
269
270 static struct device_driver i2c_powermac_driver = {
271         .name = "i2c-powermac",
272         .bus = &platform_bus_type,
273         .probe = i2c_powermac_probe,
274         .remove = i2c_powermac_remove,
275 };
276
277 static int __init i2c_powermac_init(void)
278 {
279         driver_register(&i2c_powermac_driver);
280         return 0;
281 }
282
283
284 static void __exit i2c_powermac_cleanup(void)
285 {
286         driver_unregister(&i2c_powermac_driver);
287 }
288
289 module_init(i2c_powermac_init);
290 module_exit(i2c_powermac_cleanup);