summaryrefslogtreecommitdiff
path: root/drivers/acpi/i2c_ec.c
blob: 6809c283ec5865ed7183570dbe5814fa7e9bf5a4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
/*
 * SMBus driver for ACPI Embedded Controller ($Revision: 1.3 $)
 *
 * Copyright (c) 2002, 2005 Ducrot Bruno
 * Copyright (c) 2005 Rich Townsend (tiny hacks & tweaks)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation version 2.
 */

#include <linux/version.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/acpi.h>
#include <linux/delay.h>

#include "i2c_ec.h"

#define	xudelay(t)	udelay(t)
#define	xmsleep(t)	msleep(t)

#define ACPI_EC_HC_COMPONENT	0x00080000
#define ACPI_EC_HC_CLASS	"ec_hc_smbus"
#define ACPI_EC_HC_HID		"ACPI0001"
#define ACPI_EC_HC_DRIVER_NAME	"ACPI EC HC smbus driver"
#define ACPI_EC_HC_DEVICE_NAME	"EC HC smbus"

#define _COMPONENT		ACPI_EC_HC_COMPONENT

ACPI_MODULE_NAME("acpi_smbus")

static int acpi_ec_hc_add(struct acpi_device *device);
static int acpi_ec_hc_remove(struct acpi_device *device, int type);

static struct acpi_driver acpi_ec_hc_driver = {
	.name = ACPI_EC_HC_DRIVER_NAME,
	.class = ACPI_EC_HC_CLASS,
	.ids = ACPI_EC_HC_HID,
	.ops = {
		.add = acpi_ec_hc_add,
		.remove = acpi_ec_hc_remove,
		},
};

/* Various bit mask for EC_SC (R) */
#define OBF		0x01
#define IBF		0x02
#define CMD		0x08
#define BURST		0x10
#define SCI_EVT		0x20
#define SMI_EVT		0x40

/* Commands for EC_SC (W) */
#define RD_EC		0x80
#define WR_EC		0x81
#define BE_EC		0x82
#define BD_EC		0x83
#define QR_EC		0x84

/*
 * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
 */

#define ACPI_EC_SMB_PRTCL	0x00	/* protocol, PEC */
#define ACPI_EC_SMB_STS		0x01	/* status */
#define ACPI_EC_SMB_ADDR	0x02	/* address */
#define ACPI_EC_SMB_CMD		0x03	/* command */
#define ACPI_EC_SMB_DATA	0x04	/* 32 data registers */
#define ACPI_EC_SMB_BCNT	0x24	/* number of data bytes */
#define ACPI_EC_SMB_ALRM_A	0x25	/* alarm address */
#define ACPI_EC_SMB_ALRM_D	0x26	/* 2 bytes alarm data */

#define ACPI_EC_SMB_STS_DONE	0x80
#define ACPI_EC_SMB_STS_ALRM	0x40
#define ACPI_EC_SMB_STS_RES	0x20
#define ACPI_EC_SMB_STS_STATUS	0x1f

#define ACPI_EC_SMB_STATUS_OK		0x00
#define ACPI_EC_SMB_STATUS_FAIL		0x07
#define ACPI_EC_SMB_STATUS_DNAK		0x10
#define ACPI_EC_SMB_STATUS_DERR		0x11
#define ACPI_EC_SMB_STATUS_CMD_DENY	0x12
#define ACPI_EC_SMB_STATUS_UNKNOWN	0x13
#define ACPI_EC_SMB_STATUS_ACC_DENY	0x17
#define ACPI_EC_SMB_STATUS_TIMEOUT	0x18
#define ACPI_EC_SMB_STATUS_NOTSUP	0x19
#define ACPI_EC_SMB_STATUS_BUSY		0x1A
#define ACPI_EC_SMB_STATUS_PEC		0x1F

#define ACPI_EC_SMB_PRTCL_WRITE			0x00
#define ACPI_EC_SMB_PRTCL_READ			0x01
#define ACPI_EC_SMB_PRTCL_QUICK			0x02
#define ACPI_EC_SMB_PRTCL_BYTE			0x04
#define ACPI_EC_SMB_PRTCL_BYTE_DATA		0x06
#define ACPI_EC_SMB_PRTCL_WORD_DATA		0x08
#define ACPI_EC_SMB_PRTCL_BLOCK_DATA		0x0a
#define ACPI_EC_SMB_PRTCL_PROC_CALL		0x0c
#define ACPI_EC_SMB_PRTCL_BLOCK_PROC_CALL	0x0d
#define ACPI_EC_SMB_PRTCL_I2C_BLOCK_DATA	0x4a
#define ACPI_EC_SMB_PRTCL_PEC			0x80

/* Length of pre/post transaction sleep (msec) */
#define ACPI_EC_SMB_TRANSACTION_SLEEP		1
#define ACPI_EC_SMB_ACCESS_SLEEP1		1
#define ACPI_EC_SMB_ACCESS_SLEEP2		10

static int acpi_ec_smb_read(struct acpi_ec_smbus *smbus, u8 address, u8 * data)
{
	u8 val;
	int err;

	err = ec_read(smbus->base + address, &val);
	if (!err) {
		*data = val;
	}
	xmsleep(ACPI_EC_SMB_TRANSACTION_SLEEP);
	return (err);
}

static int acpi_ec_smb_write(struct acpi_ec_smbus *smbus, u8 address, u8 data)
{
	int err;

	err = ec_write(smbus->base + address, data);
	return (err);
}

static int
acpi_ec_smb_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
		   char read_write, u8 command, int size,
		   union i2c_smbus_data *data)
{
	struct acpi_ec_smbus *smbus = adap->algo_data;
	unsigned char protocol, len = 0, pec, temp[2] = { 0, 0 };
	int i;

	if (read_write == I2C_SMBUS_READ) {
		protocol = ACPI_EC_SMB_PRTCL_READ;
	} else {
		protocol = ACPI_EC_SMB_PRTCL_WRITE;
	}
	pec = (flags & I2C_CLIENT_PEC) ? ACPI_EC_SMB_PRTCL_PEC : 0;

	switch (size) {

	case I2C_SMBUS_QUICK:
		protocol |= ACPI_EC_SMB_PRTCL_QUICK;
		read_write = I2C_SMBUS_WRITE;
		break;

	case I2C_SMBUS_BYTE:
		if (read_write == I2C_SMBUS_WRITE) {
			acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->byte);
		}
		protocol |= ACPI_EC_SMB_PRTCL_BYTE;
		break;

	case I2C_SMBUS_BYTE_DATA:
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
		if (read_write == I2C_SMBUS_WRITE) {
			acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->byte);
		}
		protocol |= ACPI_EC_SMB_PRTCL_BYTE_DATA;
		break;

	case I2C_SMBUS_WORD_DATA:
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
		if (read_write == I2C_SMBUS_WRITE) {
			acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->word);
			acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + 1,
					  data->word >> 8);
		}
		protocol |= ACPI_EC_SMB_PRTCL_WORD_DATA | pec;
		break;

	case I2C_SMBUS_BLOCK_DATA:
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
		if (read_write == I2C_SMBUS_WRITE) {
			len = min_t(u8, data->block[0], 32);
			acpi_ec_smb_write(smbus, ACPI_EC_SMB_BCNT, len);
			for (i = 0; i < len; i++)
				acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + i,
						  data->block[i + 1]);
		}
		protocol |= ACPI_EC_SMB_PRTCL_BLOCK_DATA | pec;
		break;

	case I2C_SMBUS_I2C_BLOCK_DATA:
		len = min_t(u8, data->block[0], 32);
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_BCNT, len);
		if (read_write == I2C_SMBUS_WRITE) {
			for (i = 0; i < len; i++) {
				acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + i,
						  data->block[i + 1]);
			}
		}
		protocol |= ACPI_EC_SMB_PRTCL_I2C_BLOCK_DATA;
		break;

	case I2C_SMBUS_PROC_CALL:
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->word);
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + 1, data->word >> 8);
		protocol = ACPI_EC_SMB_PRTCL_PROC_CALL | pec;
		read_write = I2C_SMBUS_READ;
		break;

	case I2C_SMBUS_BLOCK_PROC_CALL:
		protocol |= pec;
		len = min_t(u8, data->block[0], 31);
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
		acpi_ec_smb_write(smbus, ACPI_EC_SMB_BCNT, len);
		for (i = 0; i < len; i++)
			acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + i,
					  data->block[i + 1]);
		protocol = ACPI_EC_SMB_PRTCL_BLOCK_PROC_CALL | pec;
		read_write = I2C_SMBUS_READ;
		break;

	default:
		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "EC SMBus adapter: "
				  "Unsupported transaction %d\n", size));
		return (-1);
	}

	acpi_ec_smb_write(smbus, ACPI_EC_SMB_ADDR, addr << 1);
	acpi_ec_smb_write(smbus, ACPI_EC_SMB_PRTCL, protocol);

	acpi_ec_smb_read(smbus, ACPI_EC_SMB_STS, temp + 0);

	if (~temp[0] & ACPI_EC_SMB_STS_DONE) {
		xudelay(500);
		acpi_ec_smb_read(smbus, ACPI_EC_SMB_STS, temp + 0);
	}
	if (~temp[0] & ACPI_EC_SMB_STS_DONE) {
		xmsleep(ACPI_EC_SMB_ACCESS_SLEEP2);
		acpi_ec_smb_read(smbus, ACPI_EC_SMB_STS, temp + 0);
	}
	if ((~temp[0] & ACPI_EC_SMB_STS_DONE)
	    || (temp[0] & ACPI_EC_SMB_STS_STATUS)) {
		return (-1);
	}

	if (read_write == I2C_SMBUS_WRITE) {
		return (0);
	}

	switch (size) {

	case I2C_SMBUS_BYTE:
	case I2C_SMBUS_BYTE_DATA:
		acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA, &data->byte);
		break;

	case I2C_SMBUS_WORD_DATA:
	case I2C_SMBUS_PROC_CALL:
		acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA, temp + 0);
		acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA + 1, temp + 1);
		data->word = (temp[1] << 8) | temp[0];
		break;

	case I2C_SMBUS_BLOCK_DATA:
	case I2C_SMBUS_BLOCK_PROC_CALL:
		len = 0;
		acpi_ec_smb_read(smbus, ACPI_EC_SMB_BCNT, &len);
		len = min_t(u8, len, 32);
	case I2C_SMBUS_I2C_BLOCK_DATA:
		for (i = 0; i < len; i++)
			acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA + i,
					 data->block + i + 1);
		data->block[0] = len;
		break;
	}

	return (0);
}

static u32 acpi_ec_smb_func(struct i2c_adapter *adapter)
{

	return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
		I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
		I2C_FUNC_SMBUS_BLOCK_DATA |
		I2C_FUNC_SMBUS_PROC_CALL |
		I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
		I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_HWPEC_CALC);
}

static struct i2c_algorithm acpi_ec_smbus_algorithm = {
	.smbus_xfer = acpi_ec_smb_access,
	.functionality = acpi_ec_smb_func,
};

static int acpi_ec_hc_add(struct acpi_device *device)
{
	int status;
	unsigned long val;
	struct acpi_ec_hc *ec_hc;
	struct acpi_ec_smbus *smbus;

	if (!device) {
		return -EINVAL;
	}

	ec_hc = kmalloc(sizeof(struct acpi_ec_hc), GFP_KERNEL);
	if (!ec_hc) {
		return -ENOMEM;
	}
	memset(ec_hc, 0, sizeof(struct acpi_ec_hc));

	smbus = kmalloc(sizeof(struct acpi_ec_smbus), GFP_KERNEL);
	if (!smbus) {
		kfree(ec_hc);
		return -ENOMEM;
	}
	memset(smbus, 0, sizeof(struct acpi_ec_smbus));

	ec_hc->handle = device->handle;
	strcpy(acpi_device_name(device), ACPI_EC_HC_DEVICE_NAME);
	strcpy(acpi_device_class(device), ACPI_EC_HC_CLASS);
	acpi_driver_data(device) = ec_hc;

	status = acpi_evaluate_integer(ec_hc->handle, "_EC", NULL, &val);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Error obtaining _EC\n"));
		kfree(ec_hc);
		kfree(smbus);
		return -EIO;
	}

	smbus->ec = acpi_driver_data(device->parent);
	smbus->base = (val & 0xff00ull) >> 8;
	smbus->alert = val & 0xffull;

	smbus->adapter.owner = THIS_MODULE;
	smbus->adapter.algo = &acpi_ec_smbus_algorithm;
	smbus->adapter.algo_data = smbus;

	if (i2c_add_adapter(&smbus->adapter)) {
		ACPI_DEBUG_PRINT((ACPI_DB_WARN,
				  "EC SMBus adapter: Failed to register adapter\n"));
		kfree(smbus);
		kfree(ec_hc);
		return -EIO;
	}

	ec_hc->smbus = smbus;

	printk(KERN_INFO PREFIX "%s [%s]\n",
	       acpi_device_name(device), acpi_device_bid(device));

	return AE_OK;
}

static int acpi_ec_hc_remove(struct acpi_device *device, int type)
{
	struct acpi_ec_hc *ec_hc;

	if (!device) {
		return -EINVAL;
	}
	ec_hc = acpi_driver_data(device);

	i2c_del_adapter(&ec_hc->smbus->adapter);
	kfree(ec_hc->smbus);
	kfree(ec_hc);

	return AE_OK;
}

static int __init acpi_ec_hc_init(void)
{
	int result;

	result = acpi_bus_register_driver(&acpi_ec_hc_driver);
	if (result < 0) {
		return -ENODEV;
	}
	return 0;
}

static void __exit acpi_ec_hc_exit(void)
{
	acpi_bus_unregister_driver(&acpi_ec_hc_driver);
}

struct acpi_ec_hc *acpi_get_ec_hc(struct acpi_device *device)
{
	return ((struct acpi_ec_hc *)acpi_driver_data(device->parent));
}

EXPORT_SYMBOL(acpi_get_ec_hc);

module_init(acpi_ec_hc_init);
module_exit(acpi_ec_hc_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ducrot Bruno");
MODULE_DESCRIPTION("ACPI EC SMBus driver");