drm: Remove duplicate "return" statement
[pandora-kernel.git] / drivers / hwmon / pmbus / ucd9000.c
1 /*
2  * Hardware monitoring driver for UCD90xxx Sequencer and System Health
3  * Controller series
4  *
5  * Copyright (C) 2011 Ericsson AB.
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 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/err.h>
26 #include <linux/slab.h>
27 #include <linux/i2c.h>
28 #include <linux/i2c/pmbus.h>
29 #include "pmbus.h"
30
31 enum chips { ucd9000, ucd90120, ucd90124, ucd9090, ucd90910 };
32
33 #define UCD9000_MONITOR_CONFIG          0xd5
34 #define UCD9000_NUM_PAGES               0xd6
35 #define UCD9000_FAN_CONFIG_INDEX        0xe7
36 #define UCD9000_FAN_CONFIG              0xe8
37 #define UCD9000_DEVICE_ID               0xfd
38
39 #define UCD9000_MON_TYPE(x)     (((x) >> 5) & 0x07)
40 #define UCD9000_MON_PAGE(x)     ((x) & 0x0f)
41
42 #define UCD9000_MON_VOLTAGE     1
43 #define UCD9000_MON_TEMPERATURE 2
44 #define UCD9000_MON_CURRENT     3
45 #define UCD9000_MON_VOLTAGE_HW  4
46
47 #define UCD9000_NUM_FAN         4
48
49 struct ucd9000_data {
50         u8 fan_data[UCD9000_NUM_FAN][I2C_SMBUS_BLOCK_MAX];
51         struct pmbus_driver_info info;
52 };
53 #define to_ucd9000_data(_info) container_of(_info, struct ucd9000_data, info)
54
55 static int ucd9000_get_fan_config(struct i2c_client *client, int fan)
56 {
57         int fan_config = 0;
58         struct ucd9000_data *data
59           = to_ucd9000_data(pmbus_get_driver_info(client));
60
61         if (data->fan_data[fan][3] & 1)
62                 fan_config |= PB_FAN_2_INSTALLED;   /* Use lower bit position */
63
64         /* Pulses/revolution */
65         fan_config |= (data->fan_data[fan][3] & 0x06) >> 1;
66
67         return fan_config;
68 }
69
70 static int ucd9000_read_byte_data(struct i2c_client *client, int page, int reg)
71 {
72         int ret = 0;
73         int fan_config;
74
75         switch (reg) {
76         case PMBUS_FAN_CONFIG_12:
77                 if (page)
78                         return -EINVAL;
79
80                 ret = ucd9000_get_fan_config(client, 0);
81                 if (ret < 0)
82                         return ret;
83                 fan_config = ret << 4;
84                 ret = ucd9000_get_fan_config(client, 1);
85                 if (ret < 0)
86                         return ret;
87                 fan_config |= ret;
88                 ret = fan_config;
89                 break;
90         case PMBUS_FAN_CONFIG_34:
91                 if (page)
92                         return -EINVAL;
93
94                 ret = ucd9000_get_fan_config(client, 2);
95                 if (ret < 0)
96                         return ret;
97                 fan_config = ret << 4;
98                 ret = ucd9000_get_fan_config(client, 3);
99                 if (ret < 0)
100                         return ret;
101                 fan_config |= ret;
102                 ret = fan_config;
103                 break;
104         default:
105                 ret = -ENODATA;
106                 break;
107         }
108         return ret;
109 }
110
111 static const struct i2c_device_id ucd9000_id[] = {
112         {"ucd9000", ucd9000},
113         {"ucd90120", ucd90120},
114         {"ucd90124", ucd90124},
115         {"ucd9090", ucd9090},
116         {"ucd90910", ucd90910},
117         {}
118 };
119 MODULE_DEVICE_TABLE(i2c, ucd9000_id);
120
121 static int ucd9000_probe(struct i2c_client *client,
122                          const struct i2c_device_id *id)
123 {
124         u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
125         struct ucd9000_data *data;
126         struct pmbus_driver_info *info;
127         const struct i2c_device_id *mid;
128         int i, ret;
129
130         if (!i2c_check_functionality(client->adapter,
131                                      I2C_FUNC_SMBUS_BYTE_DATA |
132                                      I2C_FUNC_SMBUS_BLOCK_DATA))
133                 return -ENODEV;
134
135         ret = i2c_smbus_read_block_data(client, UCD9000_DEVICE_ID,
136                                         block_buffer);
137         if (ret < 0) {
138                 dev_err(&client->dev, "Failed to read device ID\n");
139                 return ret;
140         }
141         block_buffer[ret] = '\0';
142         dev_info(&client->dev, "Device ID %s\n", block_buffer);
143
144         mid = NULL;
145         for (i = 0; i < ARRAY_SIZE(ucd9000_id); i++) {
146                 mid = &ucd9000_id[i];
147                 if (!strncasecmp(mid->name, block_buffer, strlen(mid->name)))
148                         break;
149         }
150         if (!mid || !strlen(mid->name)) {
151                 dev_err(&client->dev, "Unsupported device\n");
152                 return -ENODEV;
153         }
154
155         if (id->driver_data != ucd9000 && id->driver_data != mid->driver_data)
156                 dev_notice(&client->dev,
157                            "Device mismatch: Configured %s, detected %s\n",
158                            id->name, mid->name);
159
160         data = kzalloc(sizeof(struct ucd9000_data), GFP_KERNEL);
161         if (!data)
162                 return -ENOMEM;
163         info = &data->info;
164
165         ret = i2c_smbus_read_byte_data(client, UCD9000_NUM_PAGES);
166         if (ret < 0) {
167                 dev_err(&client->dev,
168                         "Failed to read number of active pages\n");
169                 goto out;
170         }
171         info->pages = ret;
172         if (!info->pages) {
173                 dev_err(&client->dev, "No pages configured\n");
174                 ret = -ENODEV;
175                 goto out;
176         }
177
178         /* The internal temperature sensor is always active */
179         info->func[0] = PMBUS_HAVE_TEMP;
180
181         /* Everything else is configurable */
182         ret = i2c_smbus_read_block_data(client, UCD9000_MONITOR_CONFIG,
183                                         block_buffer);
184         if (ret <= 0) {
185                 dev_err(&client->dev, "Failed to read configuration data\n");
186                 ret = -ENODEV;
187                 goto out;
188         }
189         for (i = 0; i < ret; i++) {
190                 int page = UCD9000_MON_PAGE(block_buffer[i]);
191
192                 if (page >= info->pages)
193                         continue;
194
195                 switch (UCD9000_MON_TYPE(block_buffer[i])) {
196                 case UCD9000_MON_VOLTAGE:
197                 case UCD9000_MON_VOLTAGE_HW:
198                         info->func[page] |= PMBUS_HAVE_VOUT
199                           | PMBUS_HAVE_STATUS_VOUT;
200                         break;
201                 case UCD9000_MON_TEMPERATURE:
202                         info->func[page] |= PMBUS_HAVE_TEMP2
203                           | PMBUS_HAVE_STATUS_TEMP;
204                         break;
205                 case UCD9000_MON_CURRENT:
206                         info->func[page] |= PMBUS_HAVE_IOUT
207                           | PMBUS_HAVE_STATUS_IOUT;
208                         break;
209                 default:
210                         break;
211                 }
212         }
213
214         /* Fan configuration */
215         if (mid->driver_data == ucd90124) {
216                 for (i = 0; i < UCD9000_NUM_FAN; i++) {
217                         i2c_smbus_write_byte_data(client,
218                                                   UCD9000_FAN_CONFIG_INDEX, i);
219                         ret = i2c_smbus_read_block_data(client,
220                                                         UCD9000_FAN_CONFIG,
221                                                         data->fan_data[i]);
222                         if (ret < 0)
223                                 goto out;
224                 }
225                 i2c_smbus_write_byte_data(client, UCD9000_FAN_CONFIG_INDEX, 0);
226
227                 info->read_byte_data = ucd9000_read_byte_data;
228                 info->func[0] |= PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12
229                   | PMBUS_HAVE_FAN34 | PMBUS_HAVE_STATUS_FAN34;
230         }
231
232         ret = pmbus_do_probe(client, mid, info);
233         if (ret < 0)
234                 goto out;
235         return 0;
236
237 out:
238         kfree(data);
239         return ret;
240 }
241
242 static int ucd9000_remove(struct i2c_client *client)
243 {
244         int ret;
245         struct ucd9000_data *data;
246
247         data = to_ucd9000_data(pmbus_get_driver_info(client));
248         ret = pmbus_do_remove(client);
249         kfree(data);
250         return ret;
251 }
252
253
254 /* This is the driver that will be inserted */
255 static struct i2c_driver ucd9000_driver = {
256         .driver = {
257                 .name = "ucd9000",
258         },
259         .probe = ucd9000_probe,
260         .remove = ucd9000_remove,
261         .id_table = ucd9000_id,
262 };
263
264 static int __init ucd9000_init(void)
265 {
266         return i2c_add_driver(&ucd9000_driver);
267 }
268
269 static void __exit ucd9000_exit(void)
270 {
271         i2c_del_driver(&ucd9000_driver);
272 }
273
274 MODULE_AUTHOR("Guenter Roeck");
275 MODULE_DESCRIPTION("PMBus driver for TI UCD90xxx");
276 MODULE_LICENSE("GPL");
277 module_init(ucd9000_init);
278 module_exit(ucd9000_exit);