xref: /openbmc/linux/drivers/i2c/busses/i2c-ali1563.c (revision 588b48ca)
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 
63 static struct pci_driver ali1563_pci_driver;
64 static unsigned short ali1563_smba;
65 
66 static 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 
131 static 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 
187 static 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 
234 static 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 	}
322 Done:
323 	return error;
324 }
325 
326 static 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 
334 static 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;
378 Err:
379 	return -ENODEV;
380 }
381 
382 static void ali1563_shutdown(struct pci_dev *dev)
383 {
384 	release_region(ali1563_smba, ALI1563_SMB_IOSIZE);
385 }
386 
387 static const struct i2c_algorithm ali1563_algorithm = {
388 	.smbus_xfer	= ali1563_access,
389 	.functionality	= ali1563_func,
390 };
391 
392 static struct i2c_adapter ali1563_adapter = {
393 	.owner	= THIS_MODULE,
394 	.class	= I2C_CLASS_HWMON | I2C_CLASS_SPD,
395 	.algo	= &ali1563_algorithm,
396 };
397 
398 static 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 
414 exit_shutdown:
415 	ali1563_shutdown(dev);
416 exit:
417 	dev_warn(&dev->dev, "ALi1563 SMBus probe failed (%d)\n", error);
418 	return error;
419 }
420 
421 static void ali1563_remove(struct pci_dev *dev)
422 {
423 	i2c_del_adapter(&ali1563_adapter);
424 	ali1563_shutdown(dev);
425 }
426 
427 static const struct pci_device_id ali1563_id_table[] = {
428 	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1563) },
429 	{},
430 };
431 
432 MODULE_DEVICE_TABLE(pci, ali1563_id_table);
433 
434 static 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 
441 module_pci_driver(ali1563_pci_driver);
442 
443 MODULE_LICENSE("GPL");
444