1/*
2 * SMBus 2.0 driver for AMD-8111 IO-Hub.
3 *
4 * Copyright (c) 2002 Vojtech Pavlik
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 <linux/module.h>
12#include <linux/pci.h>
13#include <linux/kernel.h>
14#include <linux/stddef.h>
15#include <linux/ioport.h>
16#include <linux/i2c.h>
17#include <linux/delay.h>
18#include <linux/acpi.h>
19#include <linux/slab.h>
20#include <linux/io.h>
21
22MODULE_LICENSE("GPL");
23MODULE_AUTHOR ("Vojtech Pavlik <vojtech@suse.cz>");
24MODULE_DESCRIPTION("AMD8111 SMBus 2.0 driver");
25
26struct amd_smbus {
27	struct pci_dev *dev;
28	struct i2c_adapter adapter;
29	int base;
30	int size;
31};
32
33static struct pci_driver amd8111_driver;
34
35/*
36 * AMD PCI control registers definitions.
37 */
38
39#define AMD_PCI_MISC	0x48
40
41#define AMD_PCI_MISC_SCI	0x04	/* deliver SCI */
42#define AMD_PCI_MISC_INT	0x02	/* deliver PCI IRQ */
43#define AMD_PCI_MISC_SPEEDUP	0x01	/* 16x clock speedup */
44
45/*
46 * ACPI 2.0 chapter 13 PCI interface definitions.
47 */
48
49#define AMD_EC_DATA	0x00	/* data register */
50#define AMD_EC_SC	0x04	/* status of controller */
51#define AMD_EC_CMD	0x04	/* command register */
52#define AMD_EC_ICR	0x08	/* interrupt control register */
53
54#define AMD_EC_SC_SMI	0x04	/* smi event pending */
55#define AMD_EC_SC_SCI	0x02	/* sci event pending */
56#define AMD_EC_SC_BURST	0x01	/* burst mode enabled */
57#define AMD_EC_SC_CMD	0x08	/* byte in data reg is command */
58#define AMD_EC_SC_IBF	0x02	/* data ready for embedded controller */
59#define AMD_EC_SC_OBF	0x01	/* data ready for host */
60
61#define AMD_EC_CMD_RD	0x80	/* read EC */
62#define AMD_EC_CMD_WR	0x81	/* write EC */
63#define AMD_EC_CMD_BE	0x82	/* enable burst mode */
64#define AMD_EC_CMD_BD	0x83	/* disable burst mode */
65#define AMD_EC_CMD_QR	0x84	/* query EC */
66
67/*
68 * ACPI 2.0 chapter 13 access of registers of the EC
69 */
70
71static int amd_ec_wait_write(struct amd_smbus *smbus)
72{
73	int timeout = 500;
74
75	while ((inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_IBF) && --timeout)
76		udelay(1);
77
78	if (!timeout) {
79		dev_warn(&smbus->dev->dev,
80			 "Timeout while waiting for IBF to clear\n");
81		return -ETIMEDOUT;
82	}
83
84	return 0;
85}
86
87static int amd_ec_wait_read(struct amd_smbus *smbus)
88{
89	int timeout = 500;
90
91	while ((~inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_OBF) && --timeout)
92		udelay(1);
93
94	if (!timeout) {
95		dev_warn(&smbus->dev->dev,
96			 "Timeout while waiting for OBF to set\n");
97		return -ETIMEDOUT;
98	}
99
100	return 0;
101}
102
103static int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
104		unsigned char *data)
105{
106	int status;
107
108	status = amd_ec_wait_write(smbus);
109	if (status)
110		return status;
111	outb(AMD_EC_CMD_RD, smbus->base + AMD_EC_CMD);
112
113	status = amd_ec_wait_write(smbus);
114	if (status)
115		return status;
116	outb(address, smbus->base + AMD_EC_DATA);
117
118	status = amd_ec_wait_read(smbus);
119	if (status)
120		return status;
121	*data = inb(smbus->base + AMD_EC_DATA);
122
123	return 0;
124}
125
126static int amd_ec_write(struct amd_smbus *smbus, unsigned char address,
127		unsigned char data)
128{
129	int status;
130
131	status = amd_ec_wait_write(smbus);
132	if (status)
133		return status;
134	outb(AMD_EC_CMD_WR, smbus->base + AMD_EC_CMD);
135
136	status = amd_ec_wait_write(smbus);
137	if (status)
138		return status;
139	outb(address, smbus->base + AMD_EC_DATA);
140
141	status = amd_ec_wait_write(smbus);
142	if (status)
143		return status;
144	outb(data, smbus->base + AMD_EC_DATA);
145
146	return 0;
147}
148
149/*
150 * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
151 */
152
153#define AMD_SMB_PRTCL	0x00	/* protocol, PEC */
154#define AMD_SMB_STS	0x01	/* status */
155#define AMD_SMB_ADDR	0x02	/* address */
156#define AMD_SMB_CMD	0x03	/* command */
157#define AMD_SMB_DATA	0x04	/* 32 data registers */
158#define AMD_SMB_BCNT	0x24	/* number of data bytes */
159#define AMD_SMB_ALRM_A	0x25	/* alarm address */
160#define AMD_SMB_ALRM_D	0x26	/* 2 bytes alarm data */
161
162#define AMD_SMB_STS_DONE	0x80
163#define AMD_SMB_STS_ALRM	0x40
164#define AMD_SMB_STS_RES		0x20
165#define AMD_SMB_STS_STATUS	0x1f
166
167#define AMD_SMB_STATUS_OK	0x00
168#define AMD_SMB_STATUS_FAIL	0x07
169#define AMD_SMB_STATUS_DNAK	0x10
170#define AMD_SMB_STATUS_DERR	0x11
171#define AMD_SMB_STATUS_CMD_DENY	0x12
172#define AMD_SMB_STATUS_UNKNOWN	0x13
173#define AMD_SMB_STATUS_ACC_DENY	0x17
174#define AMD_SMB_STATUS_TIMEOUT	0x18
175#define AMD_SMB_STATUS_NOTSUP	0x19
176#define AMD_SMB_STATUS_BUSY	0x1A
177#define AMD_SMB_STATUS_PEC	0x1F
178
179#define AMD_SMB_PRTCL_WRITE		0x00
180#define AMD_SMB_PRTCL_READ		0x01
181#define AMD_SMB_PRTCL_QUICK		0x02
182#define AMD_SMB_PRTCL_BYTE		0x04
183#define AMD_SMB_PRTCL_BYTE_DATA		0x06
184#define AMD_SMB_PRTCL_WORD_DATA		0x08
185#define AMD_SMB_PRTCL_BLOCK_DATA	0x0a
186#define AMD_SMB_PRTCL_PROC_CALL		0x0c
187#define AMD_SMB_PRTCL_BLOCK_PROC_CALL	0x0d
188#define AMD_SMB_PRTCL_I2C_BLOCK_DATA	0x4a
189#define AMD_SMB_PRTCL_PEC		0x80
190
191
192static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
193		unsigned short flags, char read_write, u8 command, int size,
194		union i2c_smbus_data * data)
195{
196	struct amd_smbus *smbus = adap->algo_data;
197	unsigned char protocol, len, pec, temp[2];
198	int i, status;
199
200	protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ
201						  : AMD_SMB_PRTCL_WRITE;
202	pec = (flags & I2C_CLIENT_PEC) ? AMD_SMB_PRTCL_PEC : 0;
203
204	switch (size) {
205		case I2C_SMBUS_QUICK:
206			protocol |= AMD_SMB_PRTCL_QUICK;
207			read_write = I2C_SMBUS_WRITE;
208			break;
209
210		case I2C_SMBUS_BYTE:
211			if (read_write == I2C_SMBUS_WRITE) {
212				status = amd_ec_write(smbus, AMD_SMB_CMD,
213						      command);
214				if (status)
215					return status;
216			}
217			protocol |= AMD_SMB_PRTCL_BYTE;
218			break;
219
220		case I2C_SMBUS_BYTE_DATA:
221			status = amd_ec_write(smbus, AMD_SMB_CMD, command);
222			if (status)
223				return status;
224			if (read_write == I2C_SMBUS_WRITE) {
225				status = amd_ec_write(smbus, AMD_SMB_DATA,
226						      data->byte);
227				if (status)
228					return status;
229			}
230			protocol |= AMD_SMB_PRTCL_BYTE_DATA;
231			break;
232
233		case I2C_SMBUS_WORD_DATA:
234			status = amd_ec_write(smbus, AMD_SMB_CMD, command);
235			if (status)
236				return status;
237			if (read_write == I2C_SMBUS_WRITE) {
238				status = amd_ec_write(smbus, AMD_SMB_DATA,
239						      data->word & 0xff);
240				if (status)
241					return status;
242				status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
243						      data->word >> 8);
244				if (status)
245					return status;
246			}
247			protocol |= AMD_SMB_PRTCL_WORD_DATA | pec;
248			break;
249
250		case I2C_SMBUS_BLOCK_DATA:
251			status = amd_ec_write(smbus, AMD_SMB_CMD, command);
252			if (status)
253				return status;
254			if (read_write == I2C_SMBUS_WRITE) {
255				len = min_t(u8, data->block[0],
256					    I2C_SMBUS_BLOCK_MAX);
257				status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
258				if (status)
259					return status;
260				for (i = 0; i < len; i++) {
261					status =
262					  amd_ec_write(smbus, AMD_SMB_DATA + i,
263						       data->block[i + 1]);
264					if (status)
265						return status;
266				}
267			}
268			protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec;
269			break;
270
271		case I2C_SMBUS_I2C_BLOCK_DATA:
272			len = min_t(u8, data->block[0],
273				    I2C_SMBUS_BLOCK_MAX);
274			status = amd_ec_write(smbus, AMD_SMB_CMD, command);
275			if (status)
276				return status;
277			status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
278			if (status)
279				return status;
280			if (read_write == I2C_SMBUS_WRITE)
281				for (i = 0; i < len; i++) {
282					status =
283					  amd_ec_write(smbus, AMD_SMB_DATA + i,
284						       data->block[i + 1]);
285					if (status)
286						return status;
287				}
288			protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA;
289			break;
290
291		case I2C_SMBUS_PROC_CALL:
292			status = amd_ec_write(smbus, AMD_SMB_CMD, command);
293			if (status)
294				return status;
295			status = amd_ec_write(smbus, AMD_SMB_DATA,
296					      data->word & 0xff);
297			if (status)
298				return status;
299			status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
300					      data->word >> 8);
301			if (status)
302				return status;
303			protocol = AMD_SMB_PRTCL_PROC_CALL | pec;
304			read_write = I2C_SMBUS_READ;
305			break;
306
307		case I2C_SMBUS_BLOCK_PROC_CALL:
308			len = min_t(u8, data->block[0],
309				    I2C_SMBUS_BLOCK_MAX - 1);
310			status = amd_ec_write(smbus, AMD_SMB_CMD, command);
311			if (status)
312				return status;
313			status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
314			if (status)
315				return status;
316			for (i = 0; i < len; i++) {
317				status = amd_ec_write(smbus, AMD_SMB_DATA + i,
318						      data->block[i + 1]);
319				if (status)
320					return status;
321			}
322			protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec;
323			read_write = I2C_SMBUS_READ;
324			break;
325
326		default:
327			dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
328			return -EOPNOTSUPP;
329	}
330
331	status = amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
332	if (status)
333		return status;
334	status = amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
335	if (status)
336		return status;
337
338	status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
339	if (status)
340		return status;
341
342	if (~temp[0] & AMD_SMB_STS_DONE) {
343		udelay(500);
344		status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
345		if (status)
346			return status;
347	}
348
349	if (~temp[0] & AMD_SMB_STS_DONE) {
350		msleep(1);
351		status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
352		if (status)
353			return status;
354	}
355
356	if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS))
357		return -EIO;
358
359	if (read_write == I2C_SMBUS_WRITE)
360		return 0;
361
362	switch (size) {
363		case I2C_SMBUS_BYTE:
364		case I2C_SMBUS_BYTE_DATA:
365			status = amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
366			if (status)
367				return status;
368			break;
369
370		case I2C_SMBUS_WORD_DATA:
371		case I2C_SMBUS_PROC_CALL:
372			status = amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
373			if (status)
374				return status;
375			status = amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
376			if (status)
377				return status;
378			data->word = (temp[1] << 8) | temp[0];
379			break;
380
381		case I2C_SMBUS_BLOCK_DATA:
382		case I2C_SMBUS_BLOCK_PROC_CALL:
383			status = amd_ec_read(smbus, AMD_SMB_BCNT, &len);
384			if (status)
385				return status;
386			len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);
387		case I2C_SMBUS_I2C_BLOCK_DATA:
388			for (i = 0; i < len; i++) {
389				status = amd_ec_read(smbus, AMD_SMB_DATA + i,
390						     data->block + i + 1);
391				if (status)
392					return status;
393			}
394			data->block[0] = len;
395			break;
396	}
397
398	return 0;
399}
400
401
402static u32 amd8111_func(struct i2c_adapter *adapter)
403{
404	return	I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
405		I2C_FUNC_SMBUS_BYTE_DATA |
406		I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA |
407		I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
408		I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_PEC;
409}
410
411static const struct i2c_algorithm smbus_algorithm = {
412	.smbus_xfer = amd8111_access,
413	.functionality = amd8111_func,
414};
415
416
417static const struct pci_device_id amd8111_ids[] = {
418	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS2) },
419	{ 0, }
420};
421
422MODULE_DEVICE_TABLE (pci, amd8111_ids);
423
424static int amd8111_probe(struct pci_dev *dev, const struct pci_device_id *id)
425{
426	struct amd_smbus *smbus;
427	int error;
428
429	if (!(pci_resource_flags(dev, 0) & IORESOURCE_IO))
430		return -ENODEV;
431
432	smbus = kzalloc(sizeof(struct amd_smbus), GFP_KERNEL);
433	if (!smbus)
434		return -ENOMEM;
435
436	smbus->dev = dev;
437	smbus->base = pci_resource_start(dev, 0);
438	smbus->size = pci_resource_len(dev, 0);
439
440	error = acpi_check_resource_conflict(&dev->resource[0]);
441	if (error) {
442		error = -ENODEV;
443		goto out_kfree;
444	}
445
446	if (!request_region(smbus->base, smbus->size, amd8111_driver.name)) {
447		error = -EBUSY;
448		goto out_kfree;
449	}
450
451	smbus->adapter.owner = THIS_MODULE;
452	snprintf(smbus->adapter.name, sizeof(smbus->adapter.name),
453		"SMBus2 AMD8111 adapter at %04x", smbus->base);
454	smbus->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
455	smbus->adapter.algo = &smbus_algorithm;
456	smbus->adapter.algo_data = smbus;
457
458	/* set up the sysfs linkage to our parent device */
459	smbus->adapter.dev.parent = &dev->dev;
460
461	pci_write_config_dword(smbus->dev, AMD_PCI_MISC, 0);
462	error = i2c_add_adapter(&smbus->adapter);
463	if (error)
464		goto out_release_region;
465
466	pci_set_drvdata(dev, smbus);
467	return 0;
468
469 out_release_region:
470	release_region(smbus->base, smbus->size);
471 out_kfree:
472	kfree(smbus);
473	return error;
474}
475
476static void amd8111_remove(struct pci_dev *dev)
477{
478	struct amd_smbus *smbus = pci_get_drvdata(dev);
479
480	i2c_del_adapter(&smbus->adapter);
481	release_region(smbus->base, smbus->size);
482	kfree(smbus);
483}
484
485static struct pci_driver amd8111_driver = {
486	.name		= "amd8111_smbus2",
487	.id_table	= amd8111_ids,
488	.probe		= amd8111_probe,
489	.remove		= amd8111_remove,
490};
491
492module_pci_driver(amd8111_driver);
493