ACPI: Change acpi_evaluate_integer to support 64-bit on 32-bit kernels
[linux-2.6.git] / drivers / acpi / sbshc.c
1 /*
2  * SMBus driver for ACPI Embedded Controller (v0.1)
3  *
4  * Copyright (c) 2007 Alexey Starikovskiy
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation version 2.
9  */
10
11 #include <acpi/acpi_bus.h>
12 #include <acpi/acpi_drivers.h>
13 #include <acpi/actypes.h>
14 #include <linux/wait.h>
15 #include <linux/delay.h>
16 #include <linux/interrupt.h>
17 #include "sbshc.h"
18
19 #define ACPI_SMB_HC_CLASS       "smbus_host_controller"
20 #define ACPI_SMB_HC_DEVICE_NAME "ACPI SMBus HC"
21
22 struct acpi_smb_hc {
23         struct acpi_ec *ec;
24         struct mutex lock;
25         wait_queue_head_t wait;
26         u8 offset;
27         u8 query_bit;
28         smbus_alarm_callback callback;
29         void *context;
30 };
31
32 static int acpi_smbus_hc_add(struct acpi_device *device);
33 static int acpi_smbus_hc_remove(struct acpi_device *device, int type);
34
35 static const struct acpi_device_id sbs_device_ids[] = {
36         {"ACPI0001", 0},
37         {"ACPI0005", 0},
38         {"", 0},
39 };
40
41 MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
42
43 static struct acpi_driver acpi_smb_hc_driver = {
44         .name = "smbus_hc",
45         .class = ACPI_SMB_HC_CLASS,
46         .ids = sbs_device_ids,
47         .ops = {
48                 .add = acpi_smbus_hc_add,
49                 .remove = acpi_smbus_hc_remove,
50                 },
51 };
52
53 union acpi_smb_status {
54         u8 raw;
55         struct {
56                 u8 status:5;
57                 u8 reserved:1;
58                 u8 alarm:1;
59                 u8 done:1;
60         } fields;
61 };
62
63 enum acpi_smb_status_codes {
64         SMBUS_OK = 0,
65         SMBUS_UNKNOWN_FAILURE = 0x07,
66         SMBUS_DEVICE_ADDRESS_NACK = 0x10,
67         SMBUS_DEVICE_ERROR = 0x11,
68         SMBUS_DEVICE_COMMAND_ACCESS_DENIED = 0x12,
69         SMBUS_UNKNOWN_ERROR = 0x13,
70         SMBUS_DEVICE_ACCESS_DENIED = 0x17,
71         SMBUS_TIMEOUT = 0x18,
72         SMBUS_HOST_UNSUPPORTED_PROTOCOL = 0x19,
73         SMBUS_BUSY = 0x1a,
74         SMBUS_PEC_ERROR = 0x1f,
75 };
76
77 enum acpi_smb_offset {
78         ACPI_SMB_PROTOCOL = 0,  /* protocol, PEC */
79         ACPI_SMB_STATUS = 1,    /* status */
80         ACPI_SMB_ADDRESS = 2,   /* address */
81         ACPI_SMB_COMMAND = 3,   /* command */
82         ACPI_SMB_DATA = 4,      /* 32 data registers */
83         ACPI_SMB_BLOCK_COUNT = 0x24,    /* number of data bytes */
84         ACPI_SMB_ALARM_ADDRESS = 0x25,  /* alarm address */
85         ACPI_SMB_ALARM_DATA = 0x26,     /* 2 bytes alarm data */
86 };
87
88 static inline int smb_hc_read(struct acpi_smb_hc *hc, u8 address, u8 *data)
89 {
90         return ec_read(hc->offset + address, data);
91 }
92
93 static inline int smb_hc_write(struct acpi_smb_hc *hc, u8 address, u8 data)
94 {
95         return ec_write(hc->offset + address, data);
96 }
97
98 static inline int smb_check_done(struct acpi_smb_hc *hc)
99 {
100         union acpi_smb_status status = {.raw = 0};
101         smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw);
102         return status.fields.done && (status.fields.status == SMBUS_OK);
103 }
104
105 static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout)
106 {
107         if (wait_event_timeout(hc->wait, smb_check_done(hc),
108                                msecs_to_jiffies(timeout)))
109                 return 0;
110         /*
111          * After the timeout happens, OS will try to check the status of SMbus.
112          * If the status is what OS expected, it will be regarded as the bogus
113          * timeout.
114          */
115         if (smb_check_done(hc))
116                 return 0;
117         else
118                 return -ETIME;
119 }
120
121 static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol,
122                                   u8 address, u8 command, u8 *data, u8 length)
123 {
124         int ret = -EFAULT, i;
125         u8 temp, sz = 0;
126
127         if (!hc) {
128                 printk(KERN_ERR PREFIX "host controller is not configured\n");
129                 return ret;
130         }
131
132         mutex_lock(&hc->lock);
133         if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp))
134                 goto end;
135         if (temp) {
136                 ret = -EBUSY;
137                 goto end;
138         }
139         smb_hc_write(hc, ACPI_SMB_COMMAND, command);
140         if (!(protocol & 0x01)) {
141                 smb_hc_write(hc, ACPI_SMB_BLOCK_COUNT, length);
142                 for (i = 0; i < length; ++i)
143                         smb_hc_write(hc, ACPI_SMB_DATA + i, data[i]);
144         }
145         smb_hc_write(hc, ACPI_SMB_ADDRESS, address << 1);
146         smb_hc_write(hc, ACPI_SMB_PROTOCOL, protocol);
147         /*
148          * Wait for completion. Save the status code, data size,
149          * and data into the return package (if required by the protocol).
150          */
151         ret = wait_transaction_complete(hc, 1000);
152         if (ret || !(protocol & 0x01))
153                 goto end;
154         switch (protocol) {
155         case SMBUS_RECEIVE_BYTE:
156         case SMBUS_READ_BYTE:
157                 sz = 1;
158                 break;
159         case SMBUS_READ_WORD:
160                 sz = 2;
161                 break;
162         case SMBUS_READ_BLOCK:
163                 if (smb_hc_read(hc, ACPI_SMB_BLOCK_COUNT, &sz)) {
164                         ret = -EFAULT;
165                         goto end;
166                 }
167                 sz &= 0x1f;
168                 break;
169         }
170         for (i = 0; i < sz; ++i)
171                 smb_hc_read(hc, ACPI_SMB_DATA + i, &data[i]);
172       end:
173         mutex_unlock(&hc->lock);
174         return ret;
175 }
176
177 int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address,
178                     u8 command, u8 *data)
179 {
180         return acpi_smbus_transaction(hc, protocol, address, command, data, 0);
181 }
182
183 EXPORT_SYMBOL_GPL(acpi_smbus_read);
184
185 int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 address,
186                      u8 command, u8 *data, u8 length)
187 {
188         return acpi_smbus_transaction(hc, protocol, address, command, data, length);
189 }
190
191 EXPORT_SYMBOL_GPL(acpi_smbus_write);
192
193 int acpi_smbus_register_callback(struct acpi_smb_hc *hc,
194                                  smbus_alarm_callback callback, void *context)
195 {
196         mutex_lock(&hc->lock);
197         hc->callback = callback;
198         hc->context = context;
199         mutex_unlock(&hc->lock);
200         return 0;
201 }
202
203 EXPORT_SYMBOL_GPL(acpi_smbus_register_callback);
204
205 int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc)
206 {
207         mutex_lock(&hc->lock);
208         hc->callback = NULL;
209         hc->context = NULL;
210         mutex_unlock(&hc->lock);
211         return 0;
212 }
213
214 EXPORT_SYMBOL_GPL(acpi_smbus_unregister_callback);
215
216 static inline void acpi_smbus_callback(void *context)
217 {
218         struct acpi_smb_hc *hc = context;
219         if (hc->callback)
220                 hc->callback(hc->context);
221 }
222
223 static int smbus_alarm(void *context)
224 {
225         struct acpi_smb_hc *hc = context;
226         union acpi_smb_status status;
227         u8 address;
228         if (smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw))
229                 return 0;
230         /* Check if it is only a completion notify */
231         if (status.fields.done)
232                 wake_up(&hc->wait);
233         if (!status.fields.alarm)
234                 return 0;
235         mutex_lock(&hc->lock);
236         smb_hc_read(hc, ACPI_SMB_ALARM_ADDRESS, &address);
237         status.fields.alarm = 0;
238         smb_hc_write(hc, ACPI_SMB_STATUS, status.raw);
239         /* We are only interested in events coming from known devices */
240         switch (address >> 1) {
241                 case ACPI_SBS_CHARGER:
242                 case ACPI_SBS_MANAGER:
243                 case ACPI_SBS_BATTERY:
244                         acpi_os_execute(OSL_GPE_HANDLER,
245                                         acpi_smbus_callback, hc);
246                 default:;
247         }
248         mutex_unlock(&hc->lock);
249         return 0;
250 }
251
252 typedef int (*acpi_ec_query_func) (void *data);
253
254 extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
255                               acpi_handle handle, acpi_ec_query_func func,
256                               void *data);
257
258 static int acpi_smbus_hc_add(struct acpi_device *device)
259 {
260         int status;
261         unsigned long long val;
262         struct acpi_smb_hc *hc;
263
264         if (!device)
265                 return -EINVAL;
266
267         status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val);
268         if (ACPI_FAILURE(status)) {
269                 printk(KERN_ERR PREFIX "error obtaining _EC.\n");
270                 return -EIO;
271         }
272
273         strcpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
274         strcpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);
275
276         hc = kzalloc(sizeof(struct acpi_smb_hc), GFP_KERNEL);
277         if (!hc)
278                 return -ENOMEM;
279         mutex_init(&hc->lock);
280         init_waitqueue_head(&hc->wait);
281
282         hc->ec = acpi_driver_data(device->parent);
283         hc->offset = (val >> 8) & 0xff;
284         hc->query_bit = val & 0xff;
285         acpi_driver_data(device) = hc;
286
287         acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc);
288         printk(KERN_INFO PREFIX "SBS HC: EC = 0x%p, offset = 0x%0x, query_bit = 0x%0x\n",
289                 hc->ec, hc->offset, hc->query_bit);
290
291         return 0;
292 }
293
294 extern void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit);
295
296 static int acpi_smbus_hc_remove(struct acpi_device *device, int type)
297 {
298         struct acpi_smb_hc *hc;
299
300         if (!device)
301                 return -EINVAL;
302
303         hc = acpi_driver_data(device);
304         acpi_ec_remove_query_handler(hc->ec, hc->query_bit);
305         kfree(hc);
306         acpi_driver_data(device) = NULL;
307         return 0;
308 }
309
310 static int __init acpi_smb_hc_init(void)
311 {
312         int result;
313
314         result = acpi_bus_register_driver(&acpi_smb_hc_driver);
315         if (result < 0)
316                 return -ENODEV;
317         return 0;
318 }
319
320 static void __exit acpi_smb_hc_exit(void)
321 {
322         acpi_bus_unregister_driver(&acpi_smb_hc_driver);
323 }
324
325 module_init(acpi_smb_hc_init);
326 module_exit(acpi_smb_hc_exit);
327
328 MODULE_LICENSE("GPL");
329 MODULE_AUTHOR("Alexey Starikovskiy");
330 MODULE_DESCRIPTION("ACPI SMBus HC driver");