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