1/**
2 *	i2c-ali1563.c - i2c driver for the ALi 1563 Southbridge
3 *
4 *	Copyright (C) 2004 Patrick Mochel
5 *		      2005 Rudolf Marek <r.marek@assembler.cz>
6 *
7 *	The 1563 southbridge is deceptively similar to the 1533, with a
8 *	few notable exceptions. One of those happens to be the fact they
9 *	upgraded the i2c core to be 2.0 compliant, and happens to be almost
10 *	identical to the i2c controller found in the Intel 801 south
11 *	bridges.
12 *
13 *	This driver is based on a mix of the 15x3, 1535, and i801 drivers,
14 *	with a little help from the ALi 1563 spec.
15 *
16 *	This file is released under the GPLv2
17 */
18
19#include <linux/module.h>
20#include <linux/delay.h>
21#include <linux/i2c.h>
22#include <linux/pci.h>
23#include <linux/acpi.h>
24
25#define ALI1563_MAX_TIMEOUT	500
26#define	ALI1563_SMBBA		0x80
27#define ALI1563_SMB_IOEN	1
28#define ALI1563_SMB_HOSTEN	2
29#define ALI1563_SMB_IOSIZE	16
30
31#define SMB_HST_STS	(ali1563_smba + 0)
32#define SMB_HST_CNTL1	(ali1563_smba + 1)
33#define SMB_HST_CNTL2	(ali1563_smba + 2)
34#define SMB_HST_CMD	(ali1563_smba + 3)
35#define SMB_HST_ADD	(ali1563_smba + 4)
36#define SMB_HST_DAT0	(ali1563_smba + 5)
37#define SMB_HST_DAT1	(ali1563_smba + 6)
38#define SMB_BLK_DAT	(ali1563_smba + 7)
39
40#define HST_STS_BUSY	0x01
41#define HST_STS_INTR	0x02
42#define HST_STS_DEVERR	0x04
43#define HST_STS_BUSERR	0x08
44#define HST_STS_FAIL	0x10
45#define HST_STS_DONE	0x80
46#define HST_STS_BAD	0x1c
47
48
49#define HST_CNTL1_TIMEOUT	0x80
50#define HST_CNTL1_LAST		0x40
51
52#define HST_CNTL2_KILL		0x04
53#define HST_CNTL2_START		0x40
54#define HST_CNTL2_QUICK		0x00
55#define HST_CNTL2_BYTE		0x01
56#define HST_CNTL2_BYTE_DATA	0x02
57#define HST_CNTL2_WORD_DATA	0x03
58#define HST_CNTL2_BLOCK		0x05
59
60
61#define HST_CNTL2_SIZEMASK	0x38
62
63static struct pci_driver ali1563_pci_driver;
64static unsigned short ali1563_smba;
65
66static int ali1563_transaction(struct i2c_adapter *a, int size)
67{
68	u32 data;
69	int timeout;
70	int status = -EIO;
71
72	dev_dbg(&a->dev, "Transaction (pre): STS=%02x, CNTL1=%02x, "
73		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
74		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
75		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
76		inb_p(SMB_HST_DAT1));
77
78	data = inb_p(SMB_HST_STS);
79	if (data & HST_STS_BAD) {
80		dev_err(&a->dev, "ali1563: Trying to reset busy device\n");
81		outb_p(data | HST_STS_BAD, SMB_HST_STS);
82		data = inb_p(SMB_HST_STS);
83		if (data & HST_STS_BAD)
84			return -EBUSY;
85	}
86	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2);
87
88	timeout = ALI1563_MAX_TIMEOUT;
89	do {
90		msleep(1);
91	} while (((data = inb_p(SMB_HST_STS)) & HST_STS_BUSY) && --timeout);
92
93	dev_dbg(&a->dev, "Transaction (post): STS=%02x, CNTL1=%02x, "
94		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
95		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
96		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
97		inb_p(SMB_HST_DAT1));
98
99	if (timeout && !(data & HST_STS_BAD))
100		return 0;
101
102	if (!timeout) {
103		dev_err(&a->dev, "Timeout - Trying to KILL transaction!\n");
104		/* Issue 'kill' to host controller */
105		outb_p(HST_CNTL2_KILL, SMB_HST_CNTL2);
106		data = inb_p(SMB_HST_STS);
107		status = -ETIMEDOUT;
108	}
109
110	/* device error - no response, ignore the autodetection case */
111	if (data & HST_STS_DEVERR) {
112		if (size != HST_CNTL2_QUICK)
113			dev_err(&a->dev, "Device error!\n");
114		status = -ENXIO;
115	}
116	/* bus collision */
117	if (data & HST_STS_BUSERR) {
118		dev_err(&a->dev, "Bus collision!\n");
119		/* Issue timeout, hoping it helps */
120		outb_p(HST_CNTL1_TIMEOUT, SMB_HST_CNTL1);
121	}
122
123	if (data & HST_STS_FAIL) {
124		dev_err(&a->dev, "Cleaning fail after KILL!\n");
125		outb_p(0x0, SMB_HST_CNTL2);
126	}
127
128	return status;
129}
130
131static int ali1563_block_start(struct i2c_adapter *a)
132{
133	u32 data;
134	int timeout;
135	int status = -EIO;
136
137	dev_dbg(&a->dev, "Block (pre): STS=%02x, CNTL1=%02x, "
138		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
139		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
140		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
141		inb_p(SMB_HST_DAT1));
142
143	data = inb_p(SMB_HST_STS);
144	if (data & HST_STS_BAD) {
145		dev_warn(&a->dev, "ali1563: Trying to reset busy device\n");
146		outb_p(data | HST_STS_BAD, SMB_HST_STS);
147		data = inb_p(SMB_HST_STS);
148		if (data & HST_STS_BAD)
149			return -EBUSY;
150	}
151
152	/* Clear byte-ready bit */
153	outb_p(data | HST_STS_DONE, SMB_HST_STS);
154
155	/* Start transaction and wait for byte-ready bit to be set */
156	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2);
157
158	timeout = ALI1563_MAX_TIMEOUT;
159	do {
160		msleep(1);
161	} while (!((data = inb_p(SMB_HST_STS)) & HST_STS_DONE) && --timeout);
162
163	dev_dbg(&a->dev, "Block (post): STS=%02x, CNTL1=%02x, "
164		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
165		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
166		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
167		inb_p(SMB_HST_DAT1));
168
169	if (timeout && !(data & HST_STS_BAD))
170		return 0;
171
172	if (timeout == 0)
173		status = -ETIMEDOUT;
174
175	if (data & HST_STS_DEVERR)
176		status = -ENXIO;
177
178	dev_err(&a->dev, "SMBus Error: %s%s%s%s%s\n",
179		timeout ? "" : "Timeout ",
180		data & HST_STS_FAIL ? "Transaction Failed " : "",
181		data & HST_STS_BUSERR ? "No response or Bus Collision " : "",
182		data & HST_STS_DEVERR ? "Device Error " : "",
183		!(data & HST_STS_DONE) ? "Transaction Never Finished " : "");
184	return status;
185}
186
187static int ali1563_block(struct i2c_adapter *a,
188			 union i2c_smbus_data *data, u8 rw)
189{
190	int i, len;
191	int error = 0;
192
193	/* Do we need this? */
194	outb_p(HST_CNTL1_LAST, SMB_HST_CNTL1);
195
196	if (rw == I2C_SMBUS_WRITE) {
197		len = data->block[0];
198		if (len < 1)
199			len = 1;
200		else if (len > 32)
201			len = 32;
202		outb_p(len, SMB_HST_DAT0);
203		outb_p(data->block[1], SMB_BLK_DAT);
204	} else
205		len = 32;
206
207	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_BLOCK, SMB_HST_CNTL2);
208
209	for (i = 0; i < len; i++) {
210		if (rw == I2C_SMBUS_WRITE) {
211			outb_p(data->block[i + 1], SMB_BLK_DAT);
212			error = ali1563_block_start(a);
213			if (error)
214				break;
215		} else {
216			error = ali1563_block_start(a);
217			if (error)
218				break;
219			if (i == 0) {
220				len = inb_p(SMB_HST_DAT0);
221				if (len < 1)
222					len = 1;
223				else if (len > 32)
224					len = 32;
225			}
226			data->block[i+1] = inb_p(SMB_BLK_DAT);
227		}
228	}
229	/* Do we need this? */
230	outb_p(HST_CNTL1_LAST, SMB_HST_CNTL1);
231	return error;
232}
233
234static s32 ali1563_access(struct i2c_adapter *a, u16 addr,
235			  unsigned short flags, char rw, u8 cmd,
236			  int size, union i2c_smbus_data *data)
237{
238	int error = 0;
239	int timeout;
240	u32 reg;
241
242	for (timeout = ALI1563_MAX_TIMEOUT; timeout; timeout--) {
243		reg = inb_p(SMB_HST_STS);
244		if (!(reg & HST_STS_BUSY))
245			break;
246	}
247	if (!timeout)
248		dev_warn(&a->dev, "SMBus not idle. HST_STS = %02x\n", reg);
249	outb_p(0xff, SMB_HST_STS);
250
251	/* Map the size to what the chip understands */
252	switch (size) {
253	case I2C_SMBUS_QUICK:
254		size = HST_CNTL2_QUICK;
255		break;
256	case I2C_SMBUS_BYTE:
257		size = HST_CNTL2_BYTE;
258		break;
259	case I2C_SMBUS_BYTE_DATA:
260		size = HST_CNTL2_BYTE_DATA;
261		break;
262	case I2C_SMBUS_WORD_DATA:
263		size = HST_CNTL2_WORD_DATA;
264		break;
265	case I2C_SMBUS_BLOCK_DATA:
266		size = HST_CNTL2_BLOCK;
267		break;
268	default:
269		dev_warn(&a->dev, "Unsupported transaction %d\n", size);
270		error = -EOPNOTSUPP;
271		goto Done;
272	}
273
274	outb_p(((addr & 0x7f) << 1) | (rw & 0x01), SMB_HST_ADD);
275	outb_p((inb_p(SMB_HST_CNTL2) & ~HST_CNTL2_SIZEMASK) |
276	       (size << 3), SMB_HST_CNTL2);
277
278	/* Write the command register */
279
280	switch (size) {
281	case HST_CNTL2_BYTE:
282		if (rw == I2C_SMBUS_WRITE)
283			/* Beware it uses DAT0 register and not CMD! */
284			outb_p(cmd, SMB_HST_DAT0);
285		break;
286	case HST_CNTL2_BYTE_DATA:
287		outb_p(cmd, SMB_HST_CMD);
288		if (rw == I2C_SMBUS_WRITE)
289			outb_p(data->byte, SMB_HST_DAT0);
290		break;
291	case HST_CNTL2_WORD_DATA:
292		outb_p(cmd, SMB_HST_CMD);
293		if (rw == I2C_SMBUS_WRITE) {
294			outb_p(data->word & 0xff, SMB_HST_DAT0);
295			outb_p((data->word & 0xff00) >> 8, SMB_HST_DAT1);
296		}
297		break;
298	case HST_CNTL2_BLOCK:
299		outb_p(cmd, SMB_HST_CMD);
300		error = ali1563_block(a, data, rw);
301		goto Done;
302	}
303
304	error = ali1563_transaction(a, size);
305	if (error)
306		goto Done;
307
308	if ((rw == I2C_SMBUS_WRITE) || (size == HST_CNTL2_QUICK))
309		goto Done;
310
311	switch (size) {
312	case HST_CNTL2_BYTE:	/* Result put in SMBHSTDAT0 */
313		data->byte = inb_p(SMB_HST_DAT0);
314		break;
315	case HST_CNTL2_BYTE_DATA:
316		data->byte = inb_p(SMB_HST_DAT0);
317		break;
318	case HST_CNTL2_WORD_DATA:
319		data->word = inb_p(SMB_HST_DAT0) + (inb_p(SMB_HST_DAT1) << 8);
320		break;
321	}
322Done:
323	return error;
324}
325
326static u32 ali1563_func(struct i2c_adapter *a)
327{
328	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
329	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
330	    I2C_FUNC_SMBUS_BLOCK_DATA;
331}
332
333
334static int ali1563_setup(struct pci_dev *dev)
335{
336	u16 ctrl;
337
338	pci_read_config_word(dev, ALI1563_SMBBA, &ctrl);
339
340	/* SMB I/O Base in high 12 bits and must be aligned with the
341	 * size of the I/O space. */
342	ali1563_smba = ctrl & ~(ALI1563_SMB_IOSIZE - 1);
343	if (!ali1563_smba) {
344		dev_warn(&dev->dev, "ali1563_smba Uninitialized\n");
345		goto Err;
346	}
347
348	/* Check if device is enabled */
349	if (!(ctrl & ALI1563_SMB_HOSTEN)) {
350		dev_warn(&dev->dev, "Host Controller not enabled\n");
351		goto Err;
352	}
353	if (!(ctrl & ALI1563_SMB_IOEN)) {
354		dev_warn(&dev->dev, "I/O space not enabled, trying manually\n");
355		pci_write_config_word(dev, ALI1563_SMBBA,
356				      ctrl | ALI1563_SMB_IOEN);
357		pci_read_config_word(dev, ALI1563_SMBBA, &ctrl);
358		if (!(ctrl & ALI1563_SMB_IOEN)) {
359			dev_err(&dev->dev,
360				"I/O space still not enabled, giving up\n");
361			goto Err;
362		}
363	}
364
365	if (acpi_check_region(ali1563_smba, ALI1563_SMB_IOSIZE,
366			      ali1563_pci_driver.name))
367		goto Err;
368
369	if (!request_region(ali1563_smba, ALI1563_SMB_IOSIZE,
370			    ali1563_pci_driver.name)) {
371		dev_err(&dev->dev, "Could not allocate I/O space at 0x%04x\n",
372			ali1563_smba);
373		goto Err;
374	}
375	dev_info(&dev->dev, "Found ALi1563 SMBus at 0x%04x\n", ali1563_smba);
376
377	return 0;
378Err:
379	return -ENODEV;
380}
381
382static void ali1563_shutdown(struct pci_dev *dev)
383{
384	release_region(ali1563_smba, ALI1563_SMB_IOSIZE);
385}
386
387static const struct i2c_algorithm ali1563_algorithm = {
388	.smbus_xfer	= ali1563_access,
389	.functionality	= ali1563_func,
390};
391
392static struct i2c_adapter ali1563_adapter = {
393	.owner	= THIS_MODULE,
394	.class	= I2C_CLASS_HWMON | I2C_CLASS_SPD,
395	.algo	= &ali1563_algorithm,
396};
397
398static int ali1563_probe(struct pci_dev *dev,
399			 const struct pci_device_id *id_table)
400{
401	int error;
402
403	error = ali1563_setup(dev);
404	if (error)
405		goto exit;
406	ali1563_adapter.dev.parent = &dev->dev;
407	snprintf(ali1563_adapter.name, sizeof(ali1563_adapter.name),
408		 "SMBus ALi 1563 Adapter @ %04x", ali1563_smba);
409	error = i2c_add_adapter(&ali1563_adapter);
410	if (error)
411		goto exit_shutdown;
412	return 0;
413
414exit_shutdown:
415	ali1563_shutdown(dev);
416exit:
417	dev_warn(&dev->dev, "ALi1563 SMBus probe failed (%d)\n", error);
418	return error;
419}
420
421static void ali1563_remove(struct pci_dev *dev)
422{
423	i2c_del_adapter(&ali1563_adapter);
424	ali1563_shutdown(dev);
425}
426
427static const struct pci_device_id ali1563_id_table[] = {
428	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1563) },
429	{},
430};
431
432MODULE_DEVICE_TABLE(pci, ali1563_id_table);
433
434static struct pci_driver ali1563_pci_driver = {
435	.name		= "ali1563_smbus",
436	.id_table	= ali1563_id_table,
437	.probe		= ali1563_probe,
438	.remove		= ali1563_remove,
439};
440
441module_pci_driver(ali1563_pci_driver);
442
443MODULE_LICENSE("GPL");
444