xref: /openbmc/linux/drivers/i2c/busses/i2c-ali1563.c (revision 37be287c)
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, 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 			if ((error = ali1563_block_start(a)))
212 				break;
213 		} else {
214 			if ((error = ali1563_block_start(a)))
215 				break;
216 			if (i == 0) {
217 				len = inb_p(SMB_HST_DAT0);
218 				if (len < 1)
219 					len = 1;
220 				else if (len > 32)
221 					len = 32;
222 			}
223 			data->block[i+1] = inb_p(SMB_BLK_DAT);
224 		}
225 	}
226 	/* Do we need this? */
227 	outb_p(HST_CNTL1_LAST,SMB_HST_CNTL1);
228 	return error;
229 }
230 
231 static s32 ali1563_access(struct i2c_adapter * a, u16 addr,
232 			  unsigned short flags, char rw, u8 cmd,
233 			  int size, union i2c_smbus_data * data)
234 {
235 	int error = 0;
236 	int timeout;
237 	u32 reg;
238 
239 	for (timeout = ALI1563_MAX_TIMEOUT; timeout; timeout--) {
240 		if (!(reg = inb_p(SMB_HST_STS) & HST_STS_BUSY))
241 			break;
242 	}
243 	if (!timeout)
244 		dev_warn(&a->dev,"SMBus not idle. HST_STS = %02x\n",reg);
245 	outb_p(0xff,SMB_HST_STS);
246 
247 	/* Map the size to what the chip understands */
248 	switch (size) {
249 	case I2C_SMBUS_QUICK:
250 		size = HST_CNTL2_QUICK;
251 		break;
252 	case I2C_SMBUS_BYTE:
253 		size = HST_CNTL2_BYTE;
254 		break;
255 	case I2C_SMBUS_BYTE_DATA:
256 		size = HST_CNTL2_BYTE_DATA;
257 		break;
258 	case I2C_SMBUS_WORD_DATA:
259 		size = HST_CNTL2_WORD_DATA;
260 		break;
261 	case I2C_SMBUS_BLOCK_DATA:
262 		size = HST_CNTL2_BLOCK;
263 		break;
264 	default:
265 		dev_warn(&a->dev, "Unsupported transaction %d\n", size);
266 		error = -EOPNOTSUPP;
267 		goto Done;
268 	}
269 
270 	outb_p(((addr & 0x7f) << 1) | (rw & 0x01), SMB_HST_ADD);
271 	outb_p((inb_p(SMB_HST_CNTL2) & ~HST_CNTL2_SIZEMASK) | (size << 3), SMB_HST_CNTL2);
272 
273 	/* Write the command register */
274 
275 	switch(size) {
276 	case HST_CNTL2_BYTE:
277 		if (rw== I2C_SMBUS_WRITE)
278 			/* Beware it uses DAT0 register and not CMD! */
279 			outb_p(cmd, SMB_HST_DAT0);
280 		break;
281 	case HST_CNTL2_BYTE_DATA:
282 		outb_p(cmd, SMB_HST_CMD);
283 		if (rw == I2C_SMBUS_WRITE)
284 			outb_p(data->byte, SMB_HST_DAT0);
285 		break;
286 	case HST_CNTL2_WORD_DATA:
287 		outb_p(cmd, SMB_HST_CMD);
288 		if (rw == I2C_SMBUS_WRITE) {
289 			outb_p(data->word & 0xff, SMB_HST_DAT0);
290 			outb_p((data->word & 0xff00) >> 8, SMB_HST_DAT1);
291 		}
292 		break;
293 	case HST_CNTL2_BLOCK:
294 		outb_p(cmd, SMB_HST_CMD);
295 		error = ali1563_block(a,data,rw);
296 		goto Done;
297 	}
298 
299 	if ((error = ali1563_transaction(a, size)))
300 		goto Done;
301 
302 	if ((rw == I2C_SMBUS_WRITE) || (size == HST_CNTL2_QUICK))
303 		goto Done;
304 
305 	switch (size) {
306 	case HST_CNTL2_BYTE:	/* Result put in SMBHSTDAT0 */
307 		data->byte = inb_p(SMB_HST_DAT0);
308 		break;
309 	case HST_CNTL2_BYTE_DATA:
310 		data->byte = inb_p(SMB_HST_DAT0);
311 		break;
312 	case HST_CNTL2_WORD_DATA:
313 		data->word = inb_p(SMB_HST_DAT0) + (inb_p(SMB_HST_DAT1) << 8);
314 		break;
315 	}
316 Done:
317 	return error;
318 }
319 
320 static u32 ali1563_func(struct i2c_adapter * a)
321 {
322 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
323 	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
324 	    I2C_FUNC_SMBUS_BLOCK_DATA;
325 }
326 
327 
328 static int ali1563_setup(struct pci_dev *dev)
329 {
330 	u16 ctrl;
331 
332 	pci_read_config_word(dev,ALI1563_SMBBA,&ctrl);
333 
334 	/* SMB I/O Base in high 12 bits and must be aligned with the
335 	 * size of the I/O space. */
336 	ali1563_smba = ctrl & ~(ALI1563_SMB_IOSIZE - 1);
337 	if (!ali1563_smba) {
338 		dev_warn(&dev->dev,"ali1563_smba Uninitialized\n");
339 		goto Err;
340 	}
341 
342 	/* Check if device is enabled */
343 	if (!(ctrl & ALI1563_SMB_HOSTEN)) {
344 		dev_warn(&dev->dev, "Host Controller not enabled\n");
345 		goto Err;
346 	}
347 	if (!(ctrl & ALI1563_SMB_IOEN)) {
348 		dev_warn(&dev->dev, "I/O space not enabled, trying manually\n");
349 		pci_write_config_word(dev, ALI1563_SMBBA,
350 				      ctrl | ALI1563_SMB_IOEN);
351 		pci_read_config_word(dev, ALI1563_SMBBA, &ctrl);
352 		if (!(ctrl & ALI1563_SMB_IOEN)) {
353 			dev_err(&dev->dev, "I/O space still not enabled, "
354 				"giving up\n");
355 			goto Err;
356 		}
357 	}
358 
359 	if (acpi_check_region(ali1563_smba, ALI1563_SMB_IOSIZE,
360 			      ali1563_pci_driver.name))
361 		goto Err;
362 
363 	if (!request_region(ali1563_smba, ALI1563_SMB_IOSIZE,
364 			    ali1563_pci_driver.name)) {
365 		dev_err(&dev->dev, "Could not allocate I/O space at 0x%04x\n",
366 			ali1563_smba);
367 		goto Err;
368 	}
369 	dev_info(&dev->dev, "Found ALi1563 SMBus at 0x%04x\n", ali1563_smba);
370 
371 	return 0;
372 Err:
373 	return -ENODEV;
374 }
375 
376 static void ali1563_shutdown(struct pci_dev *dev)
377 {
378 	release_region(ali1563_smba,ALI1563_SMB_IOSIZE);
379 }
380 
381 static const struct i2c_algorithm ali1563_algorithm = {
382 	.smbus_xfer	= ali1563_access,
383 	.functionality	= ali1563_func,
384 };
385 
386 static struct i2c_adapter ali1563_adapter = {
387 	.owner	= THIS_MODULE,
388 	.class	= I2C_CLASS_HWMON | I2C_CLASS_SPD,
389 	.algo	= &ali1563_algorithm,
390 };
391 
392 static int ali1563_probe(struct pci_dev *dev,
393 			 const struct pci_device_id *id_table)
394 {
395 	int error;
396 
397 	if ((error = ali1563_setup(dev)))
398 		goto exit;
399 	ali1563_adapter.dev.parent = &dev->dev;
400 	snprintf(ali1563_adapter.name, sizeof(ali1563_adapter.name),
401 		 "SMBus ALi 1563 Adapter @ %04x", ali1563_smba);
402 	if ((error = i2c_add_adapter(&ali1563_adapter)))
403 		goto exit_shutdown;
404 	return 0;
405 
406 exit_shutdown:
407 	ali1563_shutdown(dev);
408 exit:
409 	dev_warn(&dev->dev, "ALi1563 SMBus probe failed (%d)\n", error);
410 	return error;
411 }
412 
413 static void ali1563_remove(struct pci_dev *dev)
414 {
415 	i2c_del_adapter(&ali1563_adapter);
416 	ali1563_shutdown(dev);
417 }
418 
419 static DEFINE_PCI_DEVICE_TABLE(ali1563_id_table) = {
420 	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1563) },
421 	{},
422 };
423 
424 MODULE_DEVICE_TABLE (pci, ali1563_id_table);
425 
426 static struct pci_driver ali1563_pci_driver = {
427  	.name		= "ali1563_smbus",
428 	.id_table	= ali1563_id_table,
429  	.probe		= ali1563_probe,
430 	.remove		= ali1563_remove,
431 };
432 
433 module_pci_driver(ali1563_pci_driver);
434 
435 MODULE_LICENSE("GPL");
436