Commit | Line | Data |
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91087dfa AS |
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> | |
91087dfa | 13 | #include <linux/wait.h> |
5a0e3ad6 | 14 | #include <linux/slab.h> |
91087dfa | 15 | #include <linux/delay.h> |
cc4b859c | 16 | #include <linux/module.h> |
91087dfa AS |
17 | #include <linux/interrupt.h> |
18 | #include "sbshc.h" | |
19 | ||
a192a958 LB |
20 | #define PREFIX "ACPI: " |
21 | ||
97c227cb | 22 | #define ACPI_SMB_HC_CLASS "smbus_host_ctl" |
91087dfa AS |
23 | #define ACPI_SMB_HC_DEVICE_NAME "ACPI SMBus HC" |
24 | ||
25 | struct acpi_smb_hc { | |
26 | struct acpi_ec *ec; | |
27 | struct mutex lock; | |
28 | wait_queue_head_t wait; | |
29 | u8 offset; | |
30 | u8 query_bit; | |
31 | smbus_alarm_callback callback; | |
32 | void *context; | |
33 | }; | |
34 | ||
35 | static int acpi_smbus_hc_add(struct acpi_device *device); | |
51fac838 | 36 | static int acpi_smbus_hc_remove(struct acpi_device *device); |
91087dfa AS |
37 | |
38 | static const struct acpi_device_id sbs_device_ids[] = { | |
39 | {"ACPI0001", 0}, | |
40 | {"ACPI0005", 0}, | |
41 | {"", 0}, | |
42 | }; | |
43 | ||
44 | MODULE_DEVICE_TABLE(acpi, sbs_device_ids); | |
45 | ||
46 | static struct acpi_driver acpi_smb_hc_driver = { | |
47 | .name = "smbus_hc", | |
48 | .class = ACPI_SMB_HC_CLASS, | |
49 | .ids = sbs_device_ids, | |
50 | .ops = { | |
51 | .add = acpi_smbus_hc_add, | |
52 | .remove = acpi_smbus_hc_remove, | |
53 | }, | |
54 | }; | |
55 | ||
56 | union acpi_smb_status { | |
57 | u8 raw; | |
58 | struct { | |
59 | u8 status:5; | |
60 | u8 reserved:1; | |
61 | u8 alarm:1; | |
62 | u8 done:1; | |
63 | } fields; | |
64 | }; | |
65 | ||
66 | enum acpi_smb_status_codes { | |
67 | SMBUS_OK = 0, | |
68 | SMBUS_UNKNOWN_FAILURE = 0x07, | |
69 | SMBUS_DEVICE_ADDRESS_NACK = 0x10, | |
70 | SMBUS_DEVICE_ERROR = 0x11, | |
71 | SMBUS_DEVICE_COMMAND_ACCESS_DENIED = 0x12, | |
72 | SMBUS_UNKNOWN_ERROR = 0x13, | |
73 | SMBUS_DEVICE_ACCESS_DENIED = 0x17, | |
74 | SMBUS_TIMEOUT = 0x18, | |
75 | SMBUS_HOST_UNSUPPORTED_PROTOCOL = 0x19, | |
76 | SMBUS_BUSY = 0x1a, | |
77 | SMBUS_PEC_ERROR = 0x1f, | |
78 | }; | |
79 | ||
80 | enum acpi_smb_offset { | |
81 | ACPI_SMB_PROTOCOL = 0, /* protocol, PEC */ | |
82 | ACPI_SMB_STATUS = 1, /* status */ | |
83 | ACPI_SMB_ADDRESS = 2, /* address */ | |
84 | ACPI_SMB_COMMAND = 3, /* command */ | |
85 | ACPI_SMB_DATA = 4, /* 32 data registers */ | |
86 | ACPI_SMB_BLOCK_COUNT = 0x24, /* number of data bytes */ | |
87 | ACPI_SMB_ALARM_ADDRESS = 0x25, /* alarm address */ | |
88 | ACPI_SMB_ALARM_DATA = 0x26, /* 2 bytes alarm data */ | |
89 | }; | |
90 | ||
91 | static inline int smb_hc_read(struct acpi_smb_hc *hc, u8 address, u8 *data) | |
92 | { | |
93 | return ec_read(hc->offset + address, data); | |
94 | } | |
95 | ||
96 | static inline int smb_hc_write(struct acpi_smb_hc *hc, u8 address, u8 data) | |
97 | { | |
98 | return ec_write(hc->offset + address, data); | |
99 | } | |
100 | ||
101 | static inline int smb_check_done(struct acpi_smb_hc *hc) | |
102 | { | |
103 | union acpi_smb_status status = {.raw = 0}; | |
104 | smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw); | |
105 | return status.fields.done && (status.fields.status == SMBUS_OK); | |
106 | } | |
107 | ||
108 | static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout) | |
109 | { | |
110 | if (wait_event_timeout(hc->wait, smb_check_done(hc), | |
111 | msecs_to_jiffies(timeout))) | |
112 | return 0; | |
266feefe ZY |
113 | /* |
114 | * After the timeout happens, OS will try to check the status of SMbus. | |
115 | * If the status is what OS expected, it will be regarded as the bogus | |
116 | * timeout. | |
117 | */ | |
118 | if (smb_check_done(hc)) | |
119 | return 0; | |
91087dfa AS |
120 | else |
121 | return -ETIME; | |
122 | } | |
123 | ||
e5685b9d AB |
124 | static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol, |
125 | u8 address, u8 command, u8 *data, u8 length) | |
91087dfa AS |
126 | { |
127 | int ret = -EFAULT, i; | |
128 | u8 temp, sz = 0; | |
129 | ||
bbafbecb AS |
130 | if (!hc) { |
131 | printk(KERN_ERR PREFIX "host controller is not configured\n"); | |
132 | return ret; | |
133 | } | |
134 | ||
91087dfa AS |
135 | mutex_lock(&hc->lock); |
136 | if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp)) | |
137 | goto end; | |
138 | if (temp) { | |
139 | ret = -EBUSY; | |
140 | goto end; | |
141 | } | |
142 | smb_hc_write(hc, ACPI_SMB_COMMAND, command); | |
91087dfa AS |
143 | if (!(protocol & 0x01)) { |
144 | smb_hc_write(hc, ACPI_SMB_BLOCK_COUNT, length); | |
145 | for (i = 0; i < length; ++i) | |
146 | smb_hc_write(hc, ACPI_SMB_DATA + i, data[i]); | |
147 | } | |
148 | smb_hc_write(hc, ACPI_SMB_ADDRESS, address << 1); | |
149 | smb_hc_write(hc, ACPI_SMB_PROTOCOL, protocol); | |
150 | /* | |
151 | * Wait for completion. Save the status code, data size, | |
152 | * and data into the return package (if required by the protocol). | |
153 | */ | |
154 | ret = wait_transaction_complete(hc, 1000); | |
155 | if (ret || !(protocol & 0x01)) | |
156 | goto end; | |
157 | switch (protocol) { | |
158 | case SMBUS_RECEIVE_BYTE: | |
159 | case SMBUS_READ_BYTE: | |
160 | sz = 1; | |
161 | break; | |
162 | case SMBUS_READ_WORD: | |
163 | sz = 2; | |
164 | break; | |
165 | case SMBUS_READ_BLOCK: | |
166 | if (smb_hc_read(hc, ACPI_SMB_BLOCK_COUNT, &sz)) { | |
167 | ret = -EFAULT; | |
168 | goto end; | |
169 | } | |
170 | sz &= 0x1f; | |
171 | break; | |
172 | } | |
173 | for (i = 0; i < sz; ++i) | |
174 | smb_hc_read(hc, ACPI_SMB_DATA + i, &data[i]); | |
175 | end: | |
176 | mutex_unlock(&hc->lock); | |
177 | return ret; | |
178 | } | |
179 | ||
180 | int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address, | |
181 | u8 command, u8 *data) | |
182 | { | |
183 | return acpi_smbus_transaction(hc, protocol, address, command, data, 0); | |
184 | } | |
185 | ||
186 | EXPORT_SYMBOL_GPL(acpi_smbus_read); | |
187 | ||
188 | int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 address, | |
189 | u8 command, u8 *data, u8 length) | |
190 | { | |
191 | return acpi_smbus_transaction(hc, protocol, address, command, data, length); | |
192 | } | |
193 | ||
194 | EXPORT_SYMBOL_GPL(acpi_smbus_write); | |
195 | ||
196 | int acpi_smbus_register_callback(struct acpi_smb_hc *hc, | |
197 | smbus_alarm_callback callback, void *context) | |
198 | { | |
199 | mutex_lock(&hc->lock); | |
200 | hc->callback = callback; | |
201 | hc->context = context; | |
202 | mutex_unlock(&hc->lock); | |
203 | return 0; | |
204 | } | |
205 | ||
206 | EXPORT_SYMBOL_GPL(acpi_smbus_register_callback); | |
207 | ||
208 | int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc) | |
209 | { | |
210 | mutex_lock(&hc->lock); | |
211 | hc->callback = NULL; | |
212 | hc->context = NULL; | |
213 | mutex_unlock(&hc->lock); | |
214 | return 0; | |
215 | } | |
216 | ||
217 | EXPORT_SYMBOL_GPL(acpi_smbus_unregister_callback); | |
218 | ||
c2d00f2d | 219 | static inline void acpi_smbus_callback(void *context) |
91087dfa AS |
220 | { |
221 | struct acpi_smb_hc *hc = context; | |
91087dfa AS |
222 | if (hc->callback) |
223 | hc->callback(hc->context); | |
224 | } | |
225 | ||
226 | static int smbus_alarm(void *context) | |
227 | { | |
228 | struct acpi_smb_hc *hc = context; | |
229 | union acpi_smb_status status; | |
c2d00f2d | 230 | u8 address; |
91087dfa AS |
231 | if (smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw)) |
232 | return 0; | |
233 | /* Check if it is only a completion notify */ | |
234 | if (status.fields.done) | |
235 | wake_up(&hc->wait); | |
236 | if (!status.fields.alarm) | |
237 | return 0; | |
238 | mutex_lock(&hc->lock); | |
c2d00f2d | 239 | smb_hc_read(hc, ACPI_SMB_ALARM_ADDRESS, &address); |
09f1fb41 | 240 | status.fields.alarm = 0; |
91087dfa | 241 | smb_hc_write(hc, ACPI_SMB_STATUS, status.raw); |
c2d00f2d AS |
242 | /* We are only interested in events coming from known devices */ |
243 | switch (address >> 1) { | |
244 | case ACPI_SBS_CHARGER: | |
245 | case ACPI_SBS_MANAGER: | |
246 | case ACPI_SBS_BATTERY: | |
f5347867 | 247 | acpi_os_execute(OSL_NOTIFY_HANDLER, |
c2d00f2d AS |
248 | acpi_smbus_callback, hc); |
249 | default:; | |
250 | } | |
91087dfa AS |
251 | mutex_unlock(&hc->lock); |
252 | return 0; | |
253 | } | |
254 | ||
255 | typedef int (*acpi_ec_query_func) (void *data); | |
256 | ||
257 | extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, | |
258 | acpi_handle handle, acpi_ec_query_func func, | |
259 | void *data); | |
260 | ||
261 | static int acpi_smbus_hc_add(struct acpi_device *device) | |
262 | { | |
263 | int status; | |
27663c58 | 264 | unsigned long long val; |
91087dfa AS |
265 | struct acpi_smb_hc *hc; |
266 | ||
267 | if (!device) | |
268 | return -EINVAL; | |
269 | ||
270 | status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val); | |
271 | if (ACPI_FAILURE(status)) { | |
272 | printk(KERN_ERR PREFIX "error obtaining _EC.\n"); | |
273 | return -EIO; | |
274 | } | |
275 | ||
276 | strcpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME); | |
277 | strcpy(acpi_device_class(device), ACPI_SMB_HC_CLASS); | |
278 | ||
279 | hc = kzalloc(sizeof(struct acpi_smb_hc), GFP_KERNEL); | |
280 | if (!hc) | |
281 | return -ENOMEM; | |
282 | mutex_init(&hc->lock); | |
283 | init_waitqueue_head(&hc->wait); | |
284 | ||
285 | hc->ec = acpi_driver_data(device->parent); | |
286 | hc->offset = (val >> 8) & 0xff; | |
287 | hc->query_bit = val & 0xff; | |
db89b4f0 | 288 | device->driver_data = hc; |
91087dfa AS |
289 | |
290 | acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc); | |
291 | printk(KERN_INFO PREFIX "SBS HC: EC = 0x%p, offset = 0x%0x, query_bit = 0x%0x\n", | |
292 | hc->ec, hc->offset, hc->query_bit); | |
293 | ||
294 | return 0; | |
295 | } | |
296 | ||
297 | extern void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit); | |
298 | ||
51fac838 | 299 | static int acpi_smbus_hc_remove(struct acpi_device *device) |
91087dfa AS |
300 | { |
301 | struct acpi_smb_hc *hc; | |
302 | ||
303 | if (!device) | |
304 | return -EINVAL; | |
305 | ||
306 | hc = acpi_driver_data(device); | |
307 | acpi_ec_remove_query_handler(hc->ec, hc->query_bit); | |
308 | kfree(hc); | |
db89b4f0 | 309 | device->driver_data = NULL; |
91087dfa AS |
310 | return 0; |
311 | } | |
312 | ||
e84a239e | 313 | module_acpi_driver(acpi_smb_hc_driver); |
91087dfa AS |
314 | |
315 | MODULE_LICENSE("GPL"); | |
316 | MODULE_AUTHOR("Alexey Starikovskiy"); | |
317 | MODULE_DESCRIPTION("ACPI SMBus HC driver"); |