xref: /openbmc/linux/drivers/i2c/busses/i2c-ali1563.c (revision d0b73b48)
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/init.h>
24 #include <linux/acpi.h>
25 
26 #define ALI1563_MAX_TIMEOUT	500
27 #define	ALI1563_SMBBA		0x80
28 #define ALI1563_SMB_IOEN	1
29 #define ALI1563_SMB_HOSTEN	2
30 #define ALI1563_SMB_IOSIZE	16
31 
32 #define SMB_HST_STS	(ali1563_smba + 0)
33 #define SMB_HST_CNTL1	(ali1563_smba + 1)
34 #define SMB_HST_CNTL2	(ali1563_smba + 2)
35 #define SMB_HST_CMD	(ali1563_smba + 3)
36 #define SMB_HST_ADD	(ali1563_smba + 4)
37 #define SMB_HST_DAT0	(ali1563_smba + 5)
38 #define SMB_HST_DAT1	(ali1563_smba + 6)
39 #define SMB_BLK_DAT	(ali1563_smba + 7)
40 
41 #define HST_STS_BUSY	0x01
42 #define HST_STS_INTR	0x02
43 #define HST_STS_DEVERR	0x04
44 #define HST_STS_BUSERR	0x08
45 #define HST_STS_FAIL	0x10
46 #define HST_STS_DONE	0x80
47 #define HST_STS_BAD	0x1c
48 
49 
50 #define HST_CNTL1_TIMEOUT	0x80
51 #define HST_CNTL1_LAST		0x40
52 
53 #define HST_CNTL2_KILL		0x04
54 #define HST_CNTL2_START		0x40
55 #define HST_CNTL2_QUICK		0x00
56 #define HST_CNTL2_BYTE		0x01
57 #define HST_CNTL2_BYTE_DATA	0x02
58 #define HST_CNTL2_WORD_DATA	0x03
59 #define HST_CNTL2_BLOCK		0x05
60 
61 
62 #define HST_CNTL2_SIZEMASK	0x38
63 
64 static struct pci_driver ali1563_pci_driver;
65 static unsigned short ali1563_smba;
66 
67 static int ali1563_transaction(struct i2c_adapter * a, int size)
68 {
69 	u32 data;
70 	int timeout;
71 	int status = -EIO;
72 
73 	dev_dbg(&a->dev, "Transaction (pre): STS=%02x, CNTL1=%02x, "
74 		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
75 		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
76 		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
77 		inb_p(SMB_HST_DAT1));
78 
79 	data = inb_p(SMB_HST_STS);
80 	if (data & HST_STS_BAD) {
81 		dev_err(&a->dev, "ali1563: Trying to reset busy device\n");
82 		outb_p(data | HST_STS_BAD,SMB_HST_STS);
83 		data = inb_p(SMB_HST_STS);
84 		if (data & HST_STS_BAD)
85 			return -EBUSY;
86 	}
87 	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2);
88 
89 	timeout = ALI1563_MAX_TIMEOUT;
90 	do {
91 		msleep(1);
92 	} while (((data = inb_p(SMB_HST_STS)) & HST_STS_BUSY) && --timeout);
93 
94 	dev_dbg(&a->dev, "Transaction (post): STS=%02x, CNTL1=%02x, "
95 		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
96 		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
97 		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
98 		inb_p(SMB_HST_DAT1));
99 
100 	if (timeout && !(data & HST_STS_BAD))
101 		return 0;
102 
103 	if (!timeout) {
104 		dev_err(&a->dev, "Timeout - Trying to KILL transaction!\n");
105 		/* Issue 'kill' to host controller */
106 		outb_p(HST_CNTL2_KILL,SMB_HST_CNTL2);
107 		data = inb_p(SMB_HST_STS);
108 		status = -ETIMEDOUT;
109  	}
110 
111 	/* device error - no response, ignore the autodetection case */
112 	if (data & HST_STS_DEVERR) {
113 		if (size != HST_CNTL2_QUICK)
114 			dev_err(&a->dev, "Device error!\n");
115 		status = -ENXIO;
116 	}
117 	/* bus collision */
118 	if (data & HST_STS_BUSERR) {
119 		dev_err(&a->dev, "Bus collision!\n");
120 		/* Issue timeout, hoping it helps */
121 		outb_p(HST_CNTL1_TIMEOUT,SMB_HST_CNTL1);
122 	}
123 
124 	if (data & HST_STS_FAIL) {
125 		dev_err(&a->dev, "Cleaning fail after KILL!\n");
126 		outb_p(0x0,SMB_HST_CNTL2);
127 	}
128 
129 	return status;
130 }
131 
132 static int ali1563_block_start(struct i2c_adapter * a)
133 {
134 	u32 data;
135 	int timeout;
136 	int status = -EIO;
137 
138 	dev_dbg(&a->dev, "Block (pre): STS=%02x, CNTL1=%02x, "
139 		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
140 		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
141 		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
142 		inb_p(SMB_HST_DAT1));
143 
144 	data = inb_p(SMB_HST_STS);
145 	if (data & HST_STS_BAD) {
146 		dev_warn(&a->dev,"ali1563: Trying to reset busy device\n");
147 		outb_p(data | HST_STS_BAD,SMB_HST_STS);
148 		data = inb_p(SMB_HST_STS);
149 		if (data & HST_STS_BAD)
150 			return -EBUSY;
151 	}
152 
153 	/* Clear byte-ready bit */
154 	outb_p(data | HST_STS_DONE, SMB_HST_STS);
155 
156 	/* Start transaction and wait for byte-ready bit to be set */
157 	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2);
158 
159 	timeout = ALI1563_MAX_TIMEOUT;
160 	do {
161 		msleep(1);
162 	} while (!((data = inb_p(SMB_HST_STS)) & HST_STS_DONE) && --timeout);
163 
164 	dev_dbg(&a->dev, "Block (post): STS=%02x, CNTL1=%02x, "
165 		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
166 		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
167 		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
168 		inb_p(SMB_HST_DAT1));
169 
170 	if (timeout && !(data & HST_STS_BAD))
171 		return 0;
172 
173 	if (timeout == 0)
174 		status = -ETIMEDOUT;
175 
176 	if (data & HST_STS_DEVERR)
177 		status = -ENXIO;
178 
179 	dev_err(&a->dev, "SMBus Error: %s%s%s%s%s\n",
180 		timeout ? "" : "Timeout ",
181 		data & HST_STS_FAIL ? "Transaction Failed " : "",
182 		data & HST_STS_BUSERR ? "No response or Bus Collision " : "",
183 		data & HST_STS_DEVERR ? "Device Error " : "",
184 		!(data & HST_STS_DONE) ? "Transaction Never Finished " : "");
185 	return status;
186 }
187 
188 static int ali1563_block(struct i2c_adapter * a, 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 			if ((error = ali1563_block_start(a)))
213 				break;
214 		} else {
215 			if ((error = ali1563_block_start(a)))
216 				break;
217 			if (i == 0) {
218 				len = inb_p(SMB_HST_DAT0);
219 				if (len < 1)
220 					len = 1;
221 				else if (len > 32)
222 					len = 32;
223 			}
224 			data->block[i+1] = inb_p(SMB_BLK_DAT);
225 		}
226 	}
227 	/* Do we need this? */
228 	outb_p(HST_CNTL1_LAST,SMB_HST_CNTL1);
229 	return error;
230 }
231 
232 static s32 ali1563_access(struct i2c_adapter * a, u16 addr,
233 			  unsigned short flags, char rw, u8 cmd,
234 			  int size, union i2c_smbus_data * data)
235 {
236 	int error = 0;
237 	int timeout;
238 	u32 reg;
239 
240 	for (timeout = ALI1563_MAX_TIMEOUT; timeout; timeout--) {
241 		if (!(reg = inb_p(SMB_HST_STS) & HST_STS_BUSY))
242 			break;
243 	}
244 	if (!timeout)
245 		dev_warn(&a->dev,"SMBus not idle. HST_STS = %02x\n",reg);
246 	outb_p(0xff,SMB_HST_STS);
247 
248 	/* Map the size to what the chip understands */
249 	switch (size) {
250 	case I2C_SMBUS_QUICK:
251 		size = HST_CNTL2_QUICK;
252 		break;
253 	case I2C_SMBUS_BYTE:
254 		size = HST_CNTL2_BYTE;
255 		break;
256 	case I2C_SMBUS_BYTE_DATA:
257 		size = HST_CNTL2_BYTE_DATA;
258 		break;
259 	case I2C_SMBUS_WORD_DATA:
260 		size = HST_CNTL2_WORD_DATA;
261 		break;
262 	case I2C_SMBUS_BLOCK_DATA:
263 		size = HST_CNTL2_BLOCK;
264 		break;
265 	default:
266 		dev_warn(&a->dev, "Unsupported transaction %d\n", size);
267 		error = -EOPNOTSUPP;
268 		goto Done;
269 	}
270 
271 	outb_p(((addr & 0x7f) << 1) | (rw & 0x01), SMB_HST_ADD);
272 	outb_p((inb_p(SMB_HST_CNTL2) & ~HST_CNTL2_SIZEMASK) | (size << 3), SMB_HST_CNTL2);
273 
274 	/* Write the command register */
275 
276 	switch(size) {
277 	case HST_CNTL2_BYTE:
278 		if (rw== I2C_SMBUS_WRITE)
279 			/* Beware it uses DAT0 register and not CMD! */
280 			outb_p(cmd, SMB_HST_DAT0);
281 		break;
282 	case HST_CNTL2_BYTE_DATA:
283 		outb_p(cmd, SMB_HST_CMD);
284 		if (rw == I2C_SMBUS_WRITE)
285 			outb_p(data->byte, SMB_HST_DAT0);
286 		break;
287 	case HST_CNTL2_WORD_DATA:
288 		outb_p(cmd, SMB_HST_CMD);
289 		if (rw == I2C_SMBUS_WRITE) {
290 			outb_p(data->word & 0xff, SMB_HST_DAT0);
291 			outb_p((data->word & 0xff00) >> 8, SMB_HST_DAT1);
292 		}
293 		break;
294 	case HST_CNTL2_BLOCK:
295 		outb_p(cmd, SMB_HST_CMD);
296 		error = ali1563_block(a,data,rw);
297 		goto Done;
298 	}
299 
300 	if ((error = ali1563_transaction(a, size)))
301 		goto Done;
302 
303 	if ((rw == I2C_SMBUS_WRITE) || (size == HST_CNTL2_QUICK))
304 		goto Done;
305 
306 	switch (size) {
307 	case HST_CNTL2_BYTE:	/* Result put in SMBHSTDAT0 */
308 		data->byte = inb_p(SMB_HST_DAT0);
309 		break;
310 	case HST_CNTL2_BYTE_DATA:
311 		data->byte = inb_p(SMB_HST_DAT0);
312 		break;
313 	case HST_CNTL2_WORD_DATA:
314 		data->word = inb_p(SMB_HST_DAT0) + (inb_p(SMB_HST_DAT1) << 8);
315 		break;
316 	}
317 Done:
318 	return error;
319 }
320 
321 static u32 ali1563_func(struct i2c_adapter * a)
322 {
323 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
324 	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
325 	    I2C_FUNC_SMBUS_BLOCK_DATA;
326 }
327 
328 
329 static int ali1563_setup(struct pci_dev *dev)
330 {
331 	u16 ctrl;
332 
333 	pci_read_config_word(dev,ALI1563_SMBBA,&ctrl);
334 
335 	/* SMB I/O Base in high 12 bits and must be aligned with the
336 	 * size of the I/O space. */
337 	ali1563_smba = ctrl & ~(ALI1563_SMB_IOSIZE - 1);
338 	if (!ali1563_smba) {
339 		dev_warn(&dev->dev,"ali1563_smba Uninitialized\n");
340 		goto Err;
341 	}
342 
343 	/* Check if device is enabled */
344 	if (!(ctrl & ALI1563_SMB_HOSTEN)) {
345 		dev_warn(&dev->dev, "Host Controller not enabled\n");
346 		goto Err;
347 	}
348 	if (!(ctrl & ALI1563_SMB_IOEN)) {
349 		dev_warn(&dev->dev, "I/O space not enabled, trying manually\n");
350 		pci_write_config_word(dev, ALI1563_SMBBA,
351 				      ctrl | ALI1563_SMB_IOEN);
352 		pci_read_config_word(dev, ALI1563_SMBBA, &ctrl);
353 		if (!(ctrl & ALI1563_SMB_IOEN)) {
354 			dev_err(&dev->dev, "I/O space still not enabled, "
355 				"giving up\n");
356 			goto Err;
357 		}
358 	}
359 
360 	if (acpi_check_region(ali1563_smba, ALI1563_SMB_IOSIZE,
361 			      ali1563_pci_driver.name))
362 		goto Err;
363 
364 	if (!request_region(ali1563_smba, ALI1563_SMB_IOSIZE,
365 			    ali1563_pci_driver.name)) {
366 		dev_err(&dev->dev, "Could not allocate I/O space at 0x%04x\n",
367 			ali1563_smba);
368 		goto Err;
369 	}
370 	dev_info(&dev->dev, "Found ALi1563 SMBus at 0x%04x\n", ali1563_smba);
371 
372 	return 0;
373 Err:
374 	return -ENODEV;
375 }
376 
377 static void ali1563_shutdown(struct pci_dev *dev)
378 {
379 	release_region(ali1563_smba,ALI1563_SMB_IOSIZE);
380 }
381 
382 static const struct i2c_algorithm ali1563_algorithm = {
383 	.smbus_xfer	= ali1563_access,
384 	.functionality	= ali1563_func,
385 };
386 
387 static struct i2c_adapter ali1563_adapter = {
388 	.owner	= THIS_MODULE,
389 	.class	= I2C_CLASS_HWMON | I2C_CLASS_SPD,
390 	.algo	= &ali1563_algorithm,
391 };
392 
393 static int ali1563_probe(struct pci_dev *dev,
394 			 const struct pci_device_id *id_table)
395 {
396 	int error;
397 
398 	if ((error = ali1563_setup(dev)))
399 		goto exit;
400 	ali1563_adapter.dev.parent = &dev->dev;
401 	snprintf(ali1563_adapter.name, sizeof(ali1563_adapter.name),
402 		 "SMBus ALi 1563 Adapter @ %04x", ali1563_smba);
403 	if ((error = i2c_add_adapter(&ali1563_adapter)))
404 		goto exit_shutdown;
405 	return 0;
406 
407 exit_shutdown:
408 	ali1563_shutdown(dev);
409 exit:
410 	dev_warn(&dev->dev, "ALi1563 SMBus probe failed (%d)\n", error);
411 	return error;
412 }
413 
414 static void ali1563_remove(struct pci_dev *dev)
415 {
416 	i2c_del_adapter(&ali1563_adapter);
417 	ali1563_shutdown(dev);
418 }
419 
420 static DEFINE_PCI_DEVICE_TABLE(ali1563_id_table) = {
421 	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1563) },
422 	{},
423 };
424 
425 MODULE_DEVICE_TABLE (pci, ali1563_id_table);
426 
427 static struct pci_driver ali1563_pci_driver = {
428  	.name		= "ali1563_smbus",
429 	.id_table	= ali1563_id_table,
430  	.probe		= ali1563_probe,
431 	.remove		= ali1563_remove,
432 };
433 
434 module_pci_driver(ali1563_pci_driver);
435 
436 MODULE_LICENSE("GPL");
437