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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * SMBus driver for ACPI Embedded Controller (v0.1)
4 *
5 * Copyright (c) 2007 Alexey Starikovskiy
6 */
7
8#define pr_fmt(fmt) "ACPI: " fmt
9
10#include <linux/acpi.h>
11#include <linux/wait.h>
12#include <linux/slab.h>
13#include <linux/delay.h>
14#include <linux/module.h>
15#include <linux/interrupt.h>
16#include "sbshc.h"
17#include "internal.h"
18
19#define ACPI_SMB_HC_CLASS "smbus_host_ctl"
20#define ACPI_SMB_HC_DEVICE_NAME "ACPI SMBus HC"
21
22struct 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 bool done;
31};
32
33static int acpi_smbus_hc_add(struct acpi_device *device);
34static void acpi_smbus_hc_remove(struct acpi_device *device);
35
36static const struct acpi_device_id sbs_device_ids[] = {
37 {"ACPI0001", 0},
38 {"ACPI0005", 0},
39 {"", 0},
40};
41
42MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
43
44static struct acpi_driver acpi_smb_hc_driver = {
45 .name = "smbus_hc",
46 .class = ACPI_SMB_HC_CLASS,
47 .ids = sbs_device_ids,
48 .ops = {
49 .add = acpi_smbus_hc_add,
50 .remove = acpi_smbus_hc_remove,
51 },
52};
53
54union acpi_smb_status {
55 u8 raw;
56 struct {
57 u8 status:5;
58 u8 reserved:1;
59 u8 alarm:1;
60 u8 done:1;
61 } fields;
62};
63
64enum acpi_smb_status_codes {
65 SMBUS_OK = 0,
66 SMBUS_UNKNOWN_FAILURE = 0x07,
67 SMBUS_DEVICE_ADDRESS_NACK = 0x10,
68 SMBUS_DEVICE_ERROR = 0x11,
69 SMBUS_DEVICE_COMMAND_ACCESS_DENIED = 0x12,
70 SMBUS_UNKNOWN_ERROR = 0x13,
71 SMBUS_DEVICE_ACCESS_DENIED = 0x17,
72 SMBUS_TIMEOUT = 0x18,
73 SMBUS_HOST_UNSUPPORTED_PROTOCOL = 0x19,
74 SMBUS_BUSY = 0x1a,
75 SMBUS_PEC_ERROR = 0x1f,
76};
77
78enum acpi_smb_offset {
79 ACPI_SMB_PROTOCOL = 0, /* protocol, PEC */
80 ACPI_SMB_STATUS = 1, /* status */
81 ACPI_SMB_ADDRESS = 2, /* address */
82 ACPI_SMB_COMMAND = 3, /* command */
83 ACPI_SMB_DATA = 4, /* 32 data registers */
84 ACPI_SMB_BLOCK_COUNT = 0x24, /* number of data bytes */
85 ACPI_SMB_ALARM_ADDRESS = 0x25, /* alarm address */
86 ACPI_SMB_ALARM_DATA = 0x26, /* 2 bytes alarm data */
87};
88
89static inline int smb_hc_read(struct acpi_smb_hc *hc, u8 address, u8 *data)
90{
91 return ec_read(hc->offset + address, data);
92}
93
94static inline int smb_hc_write(struct acpi_smb_hc *hc, u8 address, u8 data)
95{
96 return ec_write(hc->offset + address, data);
97}
98
99static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout)
100{
101 if (wait_event_timeout(hc->wait, hc->done, msecs_to_jiffies(timeout)))
102 return 0;
103 return -ETIME;
104}
105
106static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol,
107 u8 address, u8 command, u8 *data, u8 length)
108{
109 int ret = -EFAULT, i;
110 u8 temp, sz = 0;
111
112 if (!hc) {
113 pr_err("host controller is not configured\n");
114 return ret;
115 }
116
117 mutex_lock(&hc->lock);
118 hc->done = false;
119 if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp))
120 goto end;
121 if (temp) {
122 ret = -EBUSY;
123 goto end;
124 }
125 smb_hc_write(hc, ACPI_SMB_COMMAND, command);
126 if (!(protocol & 0x01)) {
127 smb_hc_write(hc, ACPI_SMB_BLOCK_COUNT, length);
128 for (i = 0; i < length; ++i)
129 smb_hc_write(hc, ACPI_SMB_DATA + i, data[i]);
130 }
131 smb_hc_write(hc, ACPI_SMB_ADDRESS, address << 1);
132 smb_hc_write(hc, ACPI_SMB_PROTOCOL, protocol);
133 /*
134 * Wait for completion. Save the status code, data size,
135 * and data into the return package (if required by the protocol).
136 */
137 ret = wait_transaction_complete(hc, 1000);
138 if (ret || !(protocol & 0x01))
139 goto end;
140 switch (protocol) {
141 case SMBUS_RECEIVE_BYTE:
142 case SMBUS_READ_BYTE:
143 sz = 1;
144 break;
145 case SMBUS_READ_WORD:
146 sz = 2;
147 break;
148 case SMBUS_READ_BLOCK:
149 if (smb_hc_read(hc, ACPI_SMB_BLOCK_COUNT, &sz)) {
150 ret = -EFAULT;
151 goto end;
152 }
153 sz &= 0x1f;
154 break;
155 }
156 for (i = 0; i < sz; ++i)
157 smb_hc_read(hc, ACPI_SMB_DATA + i, &data[i]);
158 end:
159 mutex_unlock(&hc->lock);
160 return ret;
161}
162
163int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address,
164 u8 command, u8 *data)
165{
166 return acpi_smbus_transaction(hc, protocol, address, command, data, 0);
167}
168
169EXPORT_SYMBOL_GPL(acpi_smbus_read);
170
171int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 address,
172 u8 command, u8 *data, u8 length)
173{
174 return acpi_smbus_transaction(hc, protocol, address, command, data, length);
175}
176
177EXPORT_SYMBOL_GPL(acpi_smbus_write);
178
179int acpi_smbus_register_callback(struct acpi_smb_hc *hc,
180 smbus_alarm_callback callback, void *context)
181{
182 mutex_lock(&hc->lock);
183 hc->callback = callback;
184 hc->context = context;
185 mutex_unlock(&hc->lock);
186 return 0;
187}
188
189EXPORT_SYMBOL_GPL(acpi_smbus_register_callback);
190
191int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc)
192{
193 mutex_lock(&hc->lock);
194 hc->callback = NULL;
195 hc->context = NULL;
196 mutex_unlock(&hc->lock);
197 acpi_os_wait_events_complete();
198 return 0;
199}
200
201EXPORT_SYMBOL_GPL(acpi_smbus_unregister_callback);
202
203static inline void acpi_smbus_callback(void *context)
204{
205 struct acpi_smb_hc *hc = context;
206 if (hc->callback)
207 hc->callback(hc->context);
208}
209
210static int smbus_alarm(void *context)
211{
212 struct acpi_smb_hc *hc = context;
213 union acpi_smb_status status;
214 u8 address;
215 if (smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw))
216 return 0;
217 /* Check if it is only a completion notify */
218 if (status.fields.done && status.fields.status == SMBUS_OK) {
219 hc->done = true;
220 wake_up(&hc->wait);
221 }
222 if (!status.fields.alarm)
223 return 0;
224 mutex_lock(&hc->lock);
225 smb_hc_read(hc, ACPI_SMB_ALARM_ADDRESS, &address);
226 status.fields.alarm = 0;
227 smb_hc_write(hc, ACPI_SMB_STATUS, status.raw);
228 /* We are only interested in events coming from known devices */
229 switch (address >> 1) {
230 case ACPI_SBS_CHARGER:
231 case ACPI_SBS_MANAGER:
232 case ACPI_SBS_BATTERY:
233 acpi_os_execute(OSL_NOTIFY_HANDLER,
234 acpi_smbus_callback, hc);
235 }
236 mutex_unlock(&hc->lock);
237 return 0;
238}
239
240static int acpi_smbus_hc_add(struct acpi_device *device)
241{
242 int status;
243 unsigned long long val;
244 struct acpi_smb_hc *hc;
245
246 if (!device)
247 return -EINVAL;
248
249 status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val);
250 if (ACPI_FAILURE(status)) {
251 pr_err("error obtaining _EC.\n");
252 return -EIO;
253 }
254
255 strscpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
256 strscpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);
257
258 hc = kzalloc(sizeof(struct acpi_smb_hc), GFP_KERNEL);
259 if (!hc)
260 return -ENOMEM;
261 mutex_init(&hc->lock);
262 init_waitqueue_head(&hc->wait);
263
264 hc->ec = acpi_driver_data(acpi_dev_parent(device));
265 hc->offset = (val >> 8) & 0xff;
266 hc->query_bit = val & 0xff;
267 device->driver_data = hc;
268
269 acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc);
270 dev_info(&device->dev, "SBS HC: offset = 0x%0x, query_bit = 0x%0x\n",
271 hc->offset, hc->query_bit);
272
273 return 0;
274}
275
276static void acpi_smbus_hc_remove(struct acpi_device *device)
277{
278 struct acpi_smb_hc *hc;
279
280 if (!device)
281 return;
282
283 hc = acpi_driver_data(device);
284 acpi_ec_remove_query_handler(hc->ec, hc->query_bit);
285 acpi_os_wait_events_complete();
286 kfree(hc);
287 device->driver_data = NULL;
288}
289
290module_acpi_driver(acpi_smb_hc_driver);
291
292MODULE_LICENSE("GPL");
293MODULE_AUTHOR("Alexey Starikovskiy");
294MODULE_DESCRIPTION("ACPI SMBus HC driver");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * SMBus driver for ACPI Embedded Controller (v0.1)
4 *
5 * Copyright (c) 2007 Alexey Starikovskiy
6 */
7
8#define pr_fmt(fmt) "ACPI: " fmt
9
10#include <linux/acpi.h>
11#include <linux/wait.h>
12#include <linux/slab.h>
13#include <linux/delay.h>
14#include <linux/module.h>
15#include <linux/interrupt.h>
16#include "sbshc.h"
17
18#define ACPI_SMB_HC_CLASS "smbus_host_ctl"
19#define ACPI_SMB_HC_DEVICE_NAME "ACPI SMBus HC"
20
21struct acpi_smb_hc {
22 struct acpi_ec *ec;
23 struct mutex lock;
24 wait_queue_head_t wait;
25 u8 offset;
26 u8 query_bit;
27 smbus_alarm_callback callback;
28 void *context;
29 bool done;
30};
31
32static int acpi_smbus_hc_add(struct acpi_device *device);
33static int acpi_smbus_hc_remove(struct acpi_device *device);
34
35static const struct acpi_device_id sbs_device_ids[] = {
36 {"ACPI0001", 0},
37 {"ACPI0005", 0},
38 {"", 0},
39};
40
41MODULE_DEVICE_TABLE(acpi, sbs_device_ids);
42
43static 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
53union 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
63enum 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
77enum 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
88static 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
93static 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
98static int wait_transaction_complete(struct acpi_smb_hc *hc, int timeout)
99{
100 if (wait_event_timeout(hc->wait, hc->done, msecs_to_jiffies(timeout)))
101 return 0;
102 return -ETIME;
103}
104
105static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol,
106 u8 address, u8 command, u8 *data, u8 length)
107{
108 int ret = -EFAULT, i;
109 u8 temp, sz = 0;
110
111 if (!hc) {
112 pr_err("host controller is not configured\n");
113 return ret;
114 }
115
116 mutex_lock(&hc->lock);
117 hc->done = false;
118 if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp))
119 goto end;
120 if (temp) {
121 ret = -EBUSY;
122 goto end;
123 }
124 smb_hc_write(hc, ACPI_SMB_COMMAND, command);
125 if (!(protocol & 0x01)) {
126 smb_hc_write(hc, ACPI_SMB_BLOCK_COUNT, length);
127 for (i = 0; i < length; ++i)
128 smb_hc_write(hc, ACPI_SMB_DATA + i, data[i]);
129 }
130 smb_hc_write(hc, ACPI_SMB_ADDRESS, address << 1);
131 smb_hc_write(hc, ACPI_SMB_PROTOCOL, protocol);
132 /*
133 * Wait for completion. Save the status code, data size,
134 * and data into the return package (if required by the protocol).
135 */
136 ret = wait_transaction_complete(hc, 1000);
137 if (ret || !(protocol & 0x01))
138 goto end;
139 switch (protocol) {
140 case SMBUS_RECEIVE_BYTE:
141 case SMBUS_READ_BYTE:
142 sz = 1;
143 break;
144 case SMBUS_READ_WORD:
145 sz = 2;
146 break;
147 case SMBUS_READ_BLOCK:
148 if (smb_hc_read(hc, ACPI_SMB_BLOCK_COUNT, &sz)) {
149 ret = -EFAULT;
150 goto end;
151 }
152 sz &= 0x1f;
153 break;
154 }
155 for (i = 0; i < sz; ++i)
156 smb_hc_read(hc, ACPI_SMB_DATA + i, &data[i]);
157 end:
158 mutex_unlock(&hc->lock);
159 return ret;
160}
161
162int acpi_smbus_read(struct acpi_smb_hc *hc, u8 protocol, u8 address,
163 u8 command, u8 *data)
164{
165 return acpi_smbus_transaction(hc, protocol, address, command, data, 0);
166}
167
168EXPORT_SYMBOL_GPL(acpi_smbus_read);
169
170int acpi_smbus_write(struct acpi_smb_hc *hc, u8 protocol, u8 address,
171 u8 command, u8 *data, u8 length)
172{
173 return acpi_smbus_transaction(hc, protocol, address, command, data, length);
174}
175
176EXPORT_SYMBOL_GPL(acpi_smbus_write);
177
178int acpi_smbus_register_callback(struct acpi_smb_hc *hc,
179 smbus_alarm_callback callback, void *context)
180{
181 mutex_lock(&hc->lock);
182 hc->callback = callback;
183 hc->context = context;
184 mutex_unlock(&hc->lock);
185 return 0;
186}
187
188EXPORT_SYMBOL_GPL(acpi_smbus_register_callback);
189
190int acpi_smbus_unregister_callback(struct acpi_smb_hc *hc)
191{
192 mutex_lock(&hc->lock);
193 hc->callback = NULL;
194 hc->context = NULL;
195 mutex_unlock(&hc->lock);
196 acpi_os_wait_events_complete();
197 return 0;
198}
199
200EXPORT_SYMBOL_GPL(acpi_smbus_unregister_callback);
201
202static inline void acpi_smbus_callback(void *context)
203{
204 struct acpi_smb_hc *hc = context;
205 if (hc->callback)
206 hc->callback(hc->context);
207}
208
209static int smbus_alarm(void *context)
210{
211 struct acpi_smb_hc *hc = context;
212 union acpi_smb_status status;
213 u8 address;
214 if (smb_hc_read(hc, ACPI_SMB_STATUS, &status.raw))
215 return 0;
216 /* Check if it is only a completion notify */
217 if (status.fields.done && status.fields.status == SMBUS_OK) {
218 hc->done = true;
219 wake_up(&hc->wait);
220 }
221 if (!status.fields.alarm)
222 return 0;
223 mutex_lock(&hc->lock);
224 smb_hc_read(hc, ACPI_SMB_ALARM_ADDRESS, &address);
225 status.fields.alarm = 0;
226 smb_hc_write(hc, ACPI_SMB_STATUS, status.raw);
227 /* We are only interested in events coming from known devices */
228 switch (address >> 1) {
229 case ACPI_SBS_CHARGER:
230 case ACPI_SBS_MANAGER:
231 case ACPI_SBS_BATTERY:
232 acpi_os_execute(OSL_NOTIFY_HANDLER,
233 acpi_smbus_callback, hc);
234 }
235 mutex_unlock(&hc->lock);
236 return 0;
237}
238
239typedef int (*acpi_ec_query_func) (void *data);
240
241extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
242 acpi_handle handle, acpi_ec_query_func func,
243 void *data);
244
245static int acpi_smbus_hc_add(struct acpi_device *device)
246{
247 int status;
248 unsigned long long val;
249 struct acpi_smb_hc *hc;
250
251 if (!device)
252 return -EINVAL;
253
254 status = acpi_evaluate_integer(device->handle, "_EC", NULL, &val);
255 if (ACPI_FAILURE(status)) {
256 pr_err("error obtaining _EC.\n");
257 return -EIO;
258 }
259
260 strcpy(acpi_device_name(device), ACPI_SMB_HC_DEVICE_NAME);
261 strcpy(acpi_device_class(device), ACPI_SMB_HC_CLASS);
262
263 hc = kzalloc(sizeof(struct acpi_smb_hc), GFP_KERNEL);
264 if (!hc)
265 return -ENOMEM;
266 mutex_init(&hc->lock);
267 init_waitqueue_head(&hc->wait);
268
269 hc->ec = acpi_driver_data(device->parent);
270 hc->offset = (val >> 8) & 0xff;
271 hc->query_bit = val & 0xff;
272 device->driver_data = hc;
273
274 acpi_ec_add_query_handler(hc->ec, hc->query_bit, NULL, smbus_alarm, hc);
275 dev_info(&device->dev, "SBS HC: offset = 0x%0x, query_bit = 0x%0x\n",
276 hc->offset, hc->query_bit);
277
278 return 0;
279}
280
281extern void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit);
282
283static int acpi_smbus_hc_remove(struct acpi_device *device)
284{
285 struct acpi_smb_hc *hc;
286
287 if (!device)
288 return -EINVAL;
289
290 hc = acpi_driver_data(device);
291 acpi_ec_remove_query_handler(hc->ec, hc->query_bit);
292 acpi_os_wait_events_complete();
293 kfree(hc);
294 device->driver_data = NULL;
295 return 0;
296}
297
298module_acpi_driver(acpi_smb_hc_driver);
299
300MODULE_LICENSE("GPL");
301MODULE_AUTHOR("Alexey Starikovskiy");
302MODULE_DESCRIPTION("ACPI SMBus HC driver");