1/*
2    Copyright (c) 1999-2002 Merlin Hughes <merlin@merlin.org>
3
4    Shamelessly ripped from i2c-piix4.c:
5
6    Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
7    Philip Edelbrock <phil@netroedge.com>
8
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 2 of the License, or
12    (at your option) any later version.
13
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18*/
19
20/*
21    2002-04-08: Added nForce support. (Csaba Halasz)
22    2002-10-03: Fixed nForce PnP I/O port. (Michael Steil)
23    2002-12-28: Rewritten into something that resembles a Linux driver (hch)
24    2003-11-29: Added back AMD8111 removed by the previous rewrite.
25                (Philip Pokorny)
26*/
27
28/*
29   Supports AMD756, AMD766, AMD768, AMD8111 and nVidia nForce
30   Note: we assume there can only be one device, with one SMBus interface.
31*/
32
33#include <linux/module.h>
34#include <linux/pci.h>
35#include <linux/kernel.h>
36#include <linux/delay.h>
37#include <linux/stddef.h>
38#include <linux/ioport.h>
39#include <linux/i2c.h>
40#include <linux/acpi.h>
41#include <linux/io.h>
42
43/* AMD756 SMBus address offsets */
44#define SMB_ADDR_OFFSET		0xE0
45#define SMB_IOSIZE		16
46#define SMB_GLOBAL_STATUS	(0x0 + amd756_ioport)
47#define SMB_GLOBAL_ENABLE	(0x2 + amd756_ioport)
48#define SMB_HOST_ADDRESS	(0x4 + amd756_ioport)
49#define SMB_HOST_DATA		(0x6 + amd756_ioport)
50#define SMB_HOST_COMMAND	(0x8 + amd756_ioport)
51#define SMB_HOST_BLOCK_DATA	(0x9 + amd756_ioport)
52#define SMB_HAS_DATA		(0xA + amd756_ioport)
53#define SMB_HAS_DEVICE_ADDRESS	(0xC + amd756_ioport)
54#define SMB_HAS_HOST_ADDRESS	(0xE + amd756_ioport)
55#define SMB_SNOOP_ADDRESS	(0xF + amd756_ioport)
56
57/* PCI Address Constants */
58
59/* address of I/O space */
60#define SMBBA		0x058		/* mh */
61#define SMBBANFORCE	0x014
62
63/* general configuration */
64#define SMBGCFG		0x041		/* mh */
65
66/* silicon revision code */
67#define SMBREV		0x008
68
69/* Other settings */
70#define MAX_TIMEOUT	500
71
72/* AMD756 constants */
73#define AMD756_QUICK		0x00
74#define AMD756_BYTE		0x01
75#define AMD756_BYTE_DATA	0x02
76#define AMD756_WORD_DATA	0x03
77#define AMD756_PROCESS_CALL	0x04
78#define AMD756_BLOCK_DATA	0x05
79
80static struct pci_driver amd756_driver;
81static unsigned short amd756_ioport;
82
83/*
84  SMBUS event = I/O 28-29 bit 11
85     see E0 for the status bits and enabled in E2
86
87*/
88#define GS_ABRT_STS	(1 << 0)
89#define GS_COL_STS	(1 << 1)
90#define GS_PRERR_STS	(1 << 2)
91#define GS_HST_STS	(1 << 3)
92#define GS_HCYC_STS	(1 << 4)
93#define GS_TO_STS	(1 << 5)
94#define GS_SMB_STS	(1 << 11)
95
96#define GS_CLEAR_STS	(GS_ABRT_STS | GS_COL_STS | GS_PRERR_STS | \
97			 GS_HCYC_STS | GS_TO_STS )
98
99#define GE_CYC_TYPE_MASK	(7)
100#define GE_HOST_STC		(1 << 3)
101#define GE_ABORT		(1 << 5)
102
103
104static int amd756_transaction(struct i2c_adapter *adap)
105{
106	int temp;
107	int result = 0;
108	int timeout = 0;
109
110	dev_dbg(&adap->dev, "Transaction (pre): GS=%04x, GE=%04x, ADD=%04x, "
111		"DAT=%04x\n", inw_p(SMB_GLOBAL_STATUS),
112		inw_p(SMB_GLOBAL_ENABLE), inw_p(SMB_HOST_ADDRESS),
113		inb_p(SMB_HOST_DATA));
114
115	/* Make sure the SMBus host is ready to start transmitting */
116	if ((temp = inw_p(SMB_GLOBAL_STATUS)) & (GS_HST_STS | GS_SMB_STS)) {
117		dev_dbg(&adap->dev, "SMBus busy (%04x). Waiting...\n", temp);
118		do {
119			msleep(1);
120			temp = inw_p(SMB_GLOBAL_STATUS);
121		} while ((temp & (GS_HST_STS | GS_SMB_STS)) &&
122		         (timeout++ < MAX_TIMEOUT));
123		/* If the SMBus is still busy, we give up */
124		if (timeout > MAX_TIMEOUT) {
125			dev_dbg(&adap->dev, "Busy wait timeout (%04x)\n", temp);
126			goto abort;
127		}
128		timeout = 0;
129	}
130
131	/* start the transaction by setting the start bit */
132	outw_p(inw(SMB_GLOBAL_ENABLE) | GE_HOST_STC, SMB_GLOBAL_ENABLE);
133
134	/* We will always wait for a fraction of a second! */
135	do {
136		msleep(1);
137		temp = inw_p(SMB_GLOBAL_STATUS);
138	} while ((temp & GS_HST_STS) && (timeout++ < MAX_TIMEOUT));
139
140	/* If the SMBus is still busy, we give up */
141	if (timeout > MAX_TIMEOUT) {
142		dev_dbg(&adap->dev, "Completion timeout!\n");
143		goto abort;
144	}
145
146	if (temp & GS_PRERR_STS) {
147		result = -ENXIO;
148		dev_dbg(&adap->dev, "SMBus Protocol error (no response)!\n");
149	}
150
151	if (temp & GS_COL_STS) {
152		result = -EIO;
153		dev_warn(&adap->dev, "SMBus collision!\n");
154	}
155
156	if (temp & GS_TO_STS) {
157		result = -ETIMEDOUT;
158		dev_dbg(&adap->dev, "SMBus protocol timeout!\n");
159	}
160
161	if (temp & GS_HCYC_STS)
162		dev_dbg(&adap->dev, "SMBus protocol success!\n");
163
164	outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS);
165
166#ifdef DEBUG
167	if (((temp = inw_p(SMB_GLOBAL_STATUS)) & GS_CLEAR_STS) != 0x00) {
168		dev_dbg(&adap->dev,
169			"Failed reset at end of transaction (%04x)\n", temp);
170	}
171#endif
172
173	dev_dbg(&adap->dev,
174		"Transaction (post): GS=%04x, GE=%04x, ADD=%04x, DAT=%04x\n",
175		inw_p(SMB_GLOBAL_STATUS), inw_p(SMB_GLOBAL_ENABLE),
176		inw_p(SMB_HOST_ADDRESS), inb_p(SMB_HOST_DATA));
177
178	return result;
179
180 abort:
181	dev_warn(&adap->dev, "Sending abort\n");
182	outw_p(inw(SMB_GLOBAL_ENABLE) | GE_ABORT, SMB_GLOBAL_ENABLE);
183	msleep(100);
184	outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS);
185	return -EIO;
186}
187
188/* Return negative errno on error. */
189static s32 amd756_access(struct i2c_adapter * adap, u16 addr,
190		  unsigned short flags, char read_write,
191		  u8 command, int size, union i2c_smbus_data * data)
192{
193	int i, len;
194	int status;
195
196	switch (size) {
197	case I2C_SMBUS_QUICK:
198		outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
199		       SMB_HOST_ADDRESS);
200		size = AMD756_QUICK;
201		break;
202	case I2C_SMBUS_BYTE:
203		outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
204		       SMB_HOST_ADDRESS);
205		if (read_write == I2C_SMBUS_WRITE)
206			outb_p(command, SMB_HOST_DATA);
207		size = AMD756_BYTE;
208		break;
209	case I2C_SMBUS_BYTE_DATA:
210		outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
211		       SMB_HOST_ADDRESS);
212		outb_p(command, SMB_HOST_COMMAND);
213		if (read_write == I2C_SMBUS_WRITE)
214			outw_p(data->byte, SMB_HOST_DATA);
215		size = AMD756_BYTE_DATA;
216		break;
217	case I2C_SMBUS_WORD_DATA:
218		outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
219		       SMB_HOST_ADDRESS);
220		outb_p(command, SMB_HOST_COMMAND);
221		if (read_write == I2C_SMBUS_WRITE)
222			outw_p(data->word, SMB_HOST_DATA);	/* TODO: endian???? */
223		size = AMD756_WORD_DATA;
224		break;
225	case I2C_SMBUS_BLOCK_DATA:
226		outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
227		       SMB_HOST_ADDRESS);
228		outb_p(command, SMB_HOST_COMMAND);
229		if (read_write == I2C_SMBUS_WRITE) {
230			len = data->block[0];
231			if (len < 0)
232				len = 0;
233			if (len > 32)
234				len = 32;
235			outw_p(len, SMB_HOST_DATA);
236			/* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */
237			for (i = 1; i <= len; i++)
238				outb_p(data->block[i],
239				       SMB_HOST_BLOCK_DATA);
240		}
241		size = AMD756_BLOCK_DATA;
242		break;
243	default:
244		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
245		return -EOPNOTSUPP;
246	}
247
248	/* How about enabling interrupts... */
249	outw_p(size & GE_CYC_TYPE_MASK, SMB_GLOBAL_ENABLE);
250
251	status = amd756_transaction(adap);
252	if (status)
253		return status;
254
255	if ((read_write == I2C_SMBUS_WRITE) || (size == AMD756_QUICK))
256		return 0;
257
258
259	switch (size) {
260	case AMD756_BYTE:
261		data->byte = inw_p(SMB_HOST_DATA);
262		break;
263	case AMD756_BYTE_DATA:
264		data->byte = inw_p(SMB_HOST_DATA);
265		break;
266	case AMD756_WORD_DATA:
267		data->word = inw_p(SMB_HOST_DATA);	/* TODO: endian???? */
268		break;
269	case AMD756_BLOCK_DATA:
270		data->block[0] = inw_p(SMB_HOST_DATA) & 0x3f;
271		if(data->block[0] > 32)
272			data->block[0] = 32;
273		/* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */
274		for (i = 1; i <= data->block[0]; i++)
275			data->block[i] = inb_p(SMB_HOST_BLOCK_DATA);
276		break;
277	}
278
279	return 0;
280}
281
282static u32 amd756_func(struct i2c_adapter *adapter)
283{
284	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
285	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
286	    I2C_FUNC_SMBUS_BLOCK_DATA;
287}
288
289static const struct i2c_algorithm smbus_algorithm = {
290	.smbus_xfer	= amd756_access,
291	.functionality	= amd756_func,
292};
293
294struct i2c_adapter amd756_smbus = {
295	.owner		= THIS_MODULE,
296	.class          = I2C_CLASS_HWMON | I2C_CLASS_SPD,
297	.algo		= &smbus_algorithm,
298};
299
300enum chiptype { AMD756, AMD766, AMD768, NFORCE, AMD8111 };
301static const char* chipname[] = {
302	"AMD756", "AMD766", "AMD768",
303	"nVidia nForce", "AMD8111",
304};
305
306static const struct pci_device_id amd756_ids[] = {
307	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_740B),
308	  .driver_data = AMD756 },
309	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_7413),
310	  .driver_data = AMD766 },
311	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_OPUS_7443),
312	  .driver_data = AMD768 },
313	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS),
314	  .driver_data = AMD8111 },
315	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_SMBUS),
316	  .driver_data = NFORCE },
317	{ 0, }
318};
319
320MODULE_DEVICE_TABLE (pci, amd756_ids);
321
322static int amd756_probe(struct pci_dev *pdev, const struct pci_device_id *id)
323{
324	int nforce = (id->driver_data == NFORCE);
325	int error;
326	u8 temp;
327
328	if (amd756_ioport) {
329		dev_err(&pdev->dev, "Only one device supported "
330		       "(you have a strange motherboard, btw)\n");
331		return -ENODEV;
332	}
333
334	if (nforce) {
335		if (PCI_FUNC(pdev->devfn) != 1)
336			return -ENODEV;
337
338		pci_read_config_word(pdev, SMBBANFORCE, &amd756_ioport);
339		amd756_ioport &= 0xfffc;
340	} else { /* amd */
341		if (PCI_FUNC(pdev->devfn) != 3)
342			return -ENODEV;
343
344		pci_read_config_byte(pdev, SMBGCFG, &temp);
345		if ((temp & 128) == 0) {
346			dev_err(&pdev->dev,
347				"Error: SMBus controller I/O not enabled!\n");
348			return -ENODEV;
349		}
350
351		/* Determine the address of the SMBus areas */
352		/* Technically it is a dword but... */
353		pci_read_config_word(pdev, SMBBA, &amd756_ioport);
354		amd756_ioport &= 0xff00;
355		amd756_ioport += SMB_ADDR_OFFSET;
356	}
357
358	error = acpi_check_region(amd756_ioport, SMB_IOSIZE,
359				  amd756_driver.name);
360	if (error)
361		return -ENODEV;
362
363	if (!request_region(amd756_ioport, SMB_IOSIZE, amd756_driver.name)) {
364		dev_err(&pdev->dev, "SMB region 0x%x already in use!\n",
365			amd756_ioport);
366		return -ENODEV;
367	}
368
369	pci_read_config_byte(pdev, SMBREV, &temp);
370	dev_dbg(&pdev->dev, "SMBREV = 0x%X\n", temp);
371	dev_dbg(&pdev->dev, "AMD756_smba = 0x%X\n", amd756_ioport);
372
373	/* set up the sysfs linkage to our parent device */
374	amd756_smbus.dev.parent = &pdev->dev;
375
376	snprintf(amd756_smbus.name, sizeof(amd756_smbus.name),
377		 "SMBus %s adapter at %04x", chipname[id->driver_data],
378		 amd756_ioport);
379
380	error = i2c_add_adapter(&amd756_smbus);
381	if (error) {
382		dev_err(&pdev->dev,
383			"Adapter registration failed, module not inserted\n");
384		goto out_err;
385	}
386
387	return 0;
388
389 out_err:
390	release_region(amd756_ioport, SMB_IOSIZE);
391	return error;
392}
393
394static void amd756_remove(struct pci_dev *dev)
395{
396	i2c_del_adapter(&amd756_smbus);
397	release_region(amd756_ioport, SMB_IOSIZE);
398}
399
400static struct pci_driver amd756_driver = {
401	.name		= "amd756_smbus",
402	.id_table	= amd756_ids,
403	.probe		= amd756_probe,
404	.remove		= amd756_remove,
405};
406
407module_pci_driver(amd756_driver);
408
409MODULE_AUTHOR("Merlin Hughes <merlin@merlin.org>");
410MODULE_DESCRIPTION("AMD756/766/768/8111 and nVidia nForce SMBus driver");
411MODULE_LICENSE("GPL");
412
413EXPORT_SYMBOL(amd756_smbus);
414