xref: /linux/drivers/i2c/busses/i2c-nforce2.c (revision 47902f3611b392209e2a412bf7ec02dca95e666d)
1 /*
2     SMBus driver for nVidia nForce2 MCP
3 
4     Added nForce3 Pro 150  Thomas Leibold <thomas@plx.com>,
5 	Ported to 2.5 Patrick Dreker <patrick@dreker.de>,
6     Copyright (c) 2003  Hans-Frieder Vogt <hfvogt@arcor.de>,
7     Based on
8     SMBus 2.0 driver for AMD-8111 IO-Hub
9     Copyright (c) 2002 Vojtech Pavlik
10 
11     This program is free software; you can redistribute it and/or modify
12     it under the terms of the GNU General Public License as published by
13     the Free Software Foundation; either version 2 of the License, or
14     (at your option) any later version.
15 
16     This program is distributed in the hope that it will be useful,
17     but WITHOUT ANY WARRANTY; without even the implied warranty of
18     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19     GNU General Public License for more details.
20 
21     You should have received a copy of the GNU General Public License
22     along with this program; if not, write to the Free Software
23     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 */
25 
26 /*
27     SUPPORTED DEVICES		PCI ID
28     nForce2 MCP			0064
29     nForce2 Ultra 400 MCP	0084
30     nForce3 Pro150 MCP		00D4
31     nForce3 250Gb MCP		00E4
32     nForce4 MCP			0052
33     nForce4 MCP-04		0034
34     nForce MCP51		0264
35     nForce MCP55		0368
36     nForce MCP61		03EB
37     nForce MCP65		0446
38     nForce MCP67		0542
39     nForce MCP73		07D8
40     nForce MCP78S		0752
41     nForce MCP79		0AA2
42 
43     This driver supports the 2 SMBuses that are included in the MCP of the
44     nForce2/3/4/5xx chipsets.
45 */
46 
47 /* Note: we assume there can only be one nForce2, with two SMBus interfaces */
48 
49 #include <linux/module.h>
50 #include <linux/pci.h>
51 #include <linux/kernel.h>
52 #include <linux/stddef.h>
53 #include <linux/ioport.h>
54 #include <linux/init.h>
55 #include <linux/i2c.h>
56 #include <linux/delay.h>
57 #include <linux/dmi.h>
58 #include <linux/acpi.h>
59 #include <linux/slab.h>
60 #include <asm/io.h>
61 
62 MODULE_LICENSE("GPL");
63 MODULE_AUTHOR ("Hans-Frieder Vogt <hfvogt@gmx.net>");
64 MODULE_DESCRIPTION("nForce2/3/4/5xx SMBus driver");
65 
66 
67 struct nforce2_smbus {
68 	struct i2c_adapter adapter;
69 	int base;
70 	int size;
71 	int blockops;
72 	int can_abort;
73 };
74 
75 
76 /*
77  * nVidia nForce2 SMBus control register definitions
78  * (Newer incarnations use standard BARs 4 and 5 instead)
79  */
80 #define NFORCE_PCI_SMB1	0x50
81 #define NFORCE_PCI_SMB2	0x54
82 
83 
84 /*
85  * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
86  */
87 #define NVIDIA_SMB_PRTCL	(smbus->base + 0x00)	/* protocol, PEC */
88 #define NVIDIA_SMB_STS		(smbus->base + 0x01)	/* status */
89 #define NVIDIA_SMB_ADDR		(smbus->base + 0x02)	/* address */
90 #define NVIDIA_SMB_CMD		(smbus->base + 0x03)	/* command */
91 #define NVIDIA_SMB_DATA		(smbus->base + 0x04)	/* 32 data registers */
92 #define NVIDIA_SMB_BCNT		(smbus->base + 0x24)	/* number of data
93 							   bytes */
94 #define NVIDIA_SMB_STATUS_ABRT	(smbus->base + 0x3c)	/* register used to
95 							   check the status of
96 							   the abort command */
97 #define NVIDIA_SMB_CTRL		(smbus->base + 0x3e)	/* control register */
98 
99 #define NVIDIA_SMB_STATUS_ABRT_STS	0x01		/* Bit to notify that
100 							   abort succeeded */
101 #define NVIDIA_SMB_CTRL_ABORT	0x20
102 #define NVIDIA_SMB_STS_DONE	0x80
103 #define NVIDIA_SMB_STS_ALRM	0x40
104 #define NVIDIA_SMB_STS_RES	0x20
105 #define NVIDIA_SMB_STS_STATUS	0x1f
106 
107 #define NVIDIA_SMB_PRTCL_WRITE			0x00
108 #define NVIDIA_SMB_PRTCL_READ			0x01
109 #define NVIDIA_SMB_PRTCL_QUICK			0x02
110 #define NVIDIA_SMB_PRTCL_BYTE			0x04
111 #define NVIDIA_SMB_PRTCL_BYTE_DATA		0x06
112 #define NVIDIA_SMB_PRTCL_WORD_DATA		0x08
113 #define NVIDIA_SMB_PRTCL_BLOCK_DATA		0x0a
114 #define NVIDIA_SMB_PRTCL_PEC			0x80
115 
116 /* Misc definitions */
117 #define MAX_TIMEOUT	100
118 
119 /* We disable the second SMBus channel on these boards */
120 static struct dmi_system_id __devinitdata nforce2_dmi_blacklist2[] = {
121 	{
122 		.ident = "DFI Lanparty NF4 Expert",
123 		.matches = {
124 			DMI_MATCH(DMI_BOARD_VENDOR, "DFI Corp,LTD"),
125 			DMI_MATCH(DMI_BOARD_NAME, "LP UT NF4 Expert"),
126 		},
127 	},
128 	{ }
129 };
130 
131 static struct pci_driver nforce2_driver;
132 
133 /* For multiplexing support, we need a global reference to the 1st
134    SMBus channel */
135 #if defined CONFIG_I2C_NFORCE2_S4985 || defined CONFIG_I2C_NFORCE2_S4985_MODULE
136 struct i2c_adapter *nforce2_smbus;
137 EXPORT_SYMBOL_GPL(nforce2_smbus);
138 
139 static void nforce2_set_reference(struct i2c_adapter *adap)
140 {
141 	nforce2_smbus = adap;
142 }
143 #else
144 static inline void nforce2_set_reference(struct i2c_adapter *adap) { }
145 #endif
146 
147 static void nforce2_abort(struct i2c_adapter *adap)
148 {
149 	struct nforce2_smbus *smbus = adap->algo_data;
150 	int timeout = 0;
151 	unsigned char temp;
152 
153 	dev_dbg(&adap->dev, "Aborting current transaction\n");
154 
155 	outb_p(NVIDIA_SMB_CTRL_ABORT, NVIDIA_SMB_CTRL);
156 	do {
157 		msleep(1);
158 		temp = inb_p(NVIDIA_SMB_STATUS_ABRT);
159 	} while (!(temp & NVIDIA_SMB_STATUS_ABRT_STS) &&
160 			(timeout++ < MAX_TIMEOUT));
161 	if (!(temp & NVIDIA_SMB_STATUS_ABRT_STS))
162 		dev_err(&adap->dev, "Can't reset the smbus\n");
163 	outb_p(NVIDIA_SMB_STATUS_ABRT_STS, NVIDIA_SMB_STATUS_ABRT);
164 }
165 
166 static int nforce2_check_status(struct i2c_adapter *adap)
167 {
168 	struct nforce2_smbus *smbus = adap->algo_data;
169 	int timeout = 0;
170 	unsigned char temp;
171 
172 	do {
173 		msleep(1);
174 		temp = inb_p(NVIDIA_SMB_STS);
175 	} while ((!temp) && (timeout++ < MAX_TIMEOUT));
176 
177 	if (timeout > MAX_TIMEOUT) {
178 		dev_dbg(&adap->dev, "SMBus Timeout!\n");
179 		if (smbus->can_abort)
180 			nforce2_abort(adap);
181 		return -ETIMEDOUT;
182 	}
183 	if (!(temp & NVIDIA_SMB_STS_DONE) || (temp & NVIDIA_SMB_STS_STATUS)) {
184 		dev_dbg(&adap->dev, "Transaction failed (0x%02x)!\n", temp);
185 		return -EIO;
186 	}
187 	return 0;
188 }
189 
190 /* Return negative errno on error */
191 static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
192 		unsigned short flags, char read_write,
193 		u8 command, int size, union i2c_smbus_data * data)
194 {
195 	struct nforce2_smbus *smbus = adap->algo_data;
196 	unsigned char protocol, pec;
197 	u8 len;
198 	int i, status;
199 
200 	protocol = (read_write == I2C_SMBUS_READ) ? NVIDIA_SMB_PRTCL_READ :
201 		NVIDIA_SMB_PRTCL_WRITE;
202 	pec = (flags & I2C_CLIENT_PEC) ? NVIDIA_SMB_PRTCL_PEC : 0;
203 
204 	switch (size) {
205 
206 		case I2C_SMBUS_QUICK:
207 			protocol |= NVIDIA_SMB_PRTCL_QUICK;
208 			read_write = I2C_SMBUS_WRITE;
209 			break;
210 
211 		case I2C_SMBUS_BYTE:
212 			if (read_write == I2C_SMBUS_WRITE)
213 				outb_p(command, NVIDIA_SMB_CMD);
214 			protocol |= NVIDIA_SMB_PRTCL_BYTE;
215 			break;
216 
217 		case I2C_SMBUS_BYTE_DATA:
218 			outb_p(command, NVIDIA_SMB_CMD);
219 			if (read_write == I2C_SMBUS_WRITE)
220 				outb_p(data->byte, NVIDIA_SMB_DATA);
221 			protocol |= NVIDIA_SMB_PRTCL_BYTE_DATA;
222 			break;
223 
224 		case I2C_SMBUS_WORD_DATA:
225 			outb_p(command, NVIDIA_SMB_CMD);
226 			if (read_write == I2C_SMBUS_WRITE) {
227 				 outb_p(data->word, NVIDIA_SMB_DATA);
228 				 outb_p(data->word >> 8, NVIDIA_SMB_DATA+1);
229 			}
230 			protocol |= NVIDIA_SMB_PRTCL_WORD_DATA | pec;
231 			break;
232 
233 		case I2C_SMBUS_BLOCK_DATA:
234 			outb_p(command, NVIDIA_SMB_CMD);
235 			if (read_write == I2C_SMBUS_WRITE) {
236 				len = data->block[0];
237 				if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
238 					dev_err(&adap->dev,
239 						"Transaction failed "
240 						"(requested block size: %d)\n",
241 						len);
242 					return -EINVAL;
243 				}
244 				outb_p(len, NVIDIA_SMB_BCNT);
245 				for (i = 0; i < I2C_SMBUS_BLOCK_MAX; i++)
246 					outb_p(data->block[i + 1],
247 					       NVIDIA_SMB_DATA+i);
248 			}
249 			protocol |= NVIDIA_SMB_PRTCL_BLOCK_DATA | pec;
250 			break;
251 
252 		default:
253 			dev_err(&adap->dev, "Unsupported transaction %d\n", size);
254 			return -EOPNOTSUPP;
255 	}
256 
257 	outb_p((addr & 0x7f) << 1, NVIDIA_SMB_ADDR);
258 	outb_p(protocol, NVIDIA_SMB_PRTCL);
259 
260 	status = nforce2_check_status(adap);
261 	if (status)
262 		return status;
263 
264 	if (read_write == I2C_SMBUS_WRITE)
265 		return 0;
266 
267 	switch (size) {
268 
269 		case I2C_SMBUS_BYTE:
270 		case I2C_SMBUS_BYTE_DATA:
271 			data->byte = inb_p(NVIDIA_SMB_DATA);
272 			break;
273 
274 		case I2C_SMBUS_WORD_DATA:
275 			data->word = inb_p(NVIDIA_SMB_DATA) | (inb_p(NVIDIA_SMB_DATA+1) << 8);
276 			break;
277 
278 		case I2C_SMBUS_BLOCK_DATA:
279 			len = inb_p(NVIDIA_SMB_BCNT);
280 			if ((len <= 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
281 				dev_err(&adap->dev, "Transaction failed "
282 					"(received block size: 0x%02x)\n",
283 					len);
284 				return -EPROTO;
285 			}
286 			for (i = 0; i < len; i++)
287 				data->block[i+1] = inb_p(NVIDIA_SMB_DATA + i);
288 			data->block[0] = len;
289 			break;
290 	}
291 
292 	return 0;
293 }
294 
295 
296 static u32 nforce2_func(struct i2c_adapter *adapter)
297 {
298 	/* other functionality might be possible, but is not tested */
299 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
300 	       I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
301 	       I2C_FUNC_SMBUS_PEC |
302 	       (((struct nforce2_smbus*)adapter->algo_data)->blockops ?
303 		I2C_FUNC_SMBUS_BLOCK_DATA : 0);
304 }
305 
306 static struct i2c_algorithm smbus_algorithm = {
307 	.smbus_xfer	= nforce2_access,
308 	.functionality	= nforce2_func,
309 };
310 
311 
312 static const struct pci_device_id nforce2_ids[] = {
313 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS) },
314 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2S_SMBUS) },
315 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3_SMBUS) },
316 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3S_SMBUS) },
317 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE4_SMBUS) },
318 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP04_SMBUS) },
319 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS) },
320 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS) },
321 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SMBUS) },
322 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP65_SMBUS) },
323 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP67_SMBUS) },
324 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP73_SMBUS) },
325 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP78S_SMBUS) },
326 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP79_SMBUS) },
327 	{ 0 }
328 };
329 
330 MODULE_DEVICE_TABLE (pci, nforce2_ids);
331 
332 
333 static int __devinit nforce2_probe_smb (struct pci_dev *dev, int bar,
334 	int alt_reg, struct nforce2_smbus *smbus, const char *name)
335 {
336 	int error;
337 
338 	smbus->base = pci_resource_start(dev, bar);
339 	if (smbus->base) {
340 		smbus->size = pci_resource_len(dev, bar);
341 	} else {
342 		/* Older incarnations of the device used non-standard BARs */
343 		u16 iobase;
344 
345 		if (pci_read_config_word(dev, alt_reg, &iobase)
346 		    != PCIBIOS_SUCCESSFUL) {
347 			dev_err(&dev->dev, "Error reading PCI config for %s\n",
348 				name);
349 			return -EIO;
350 		}
351 
352 		smbus->base = iobase & PCI_BASE_ADDRESS_IO_MASK;
353 		smbus->size = 64;
354 	}
355 
356 	error = acpi_check_region(smbus->base, smbus->size,
357 				  nforce2_driver.name);
358 	if (error)
359 		return -1;
360 
361 	if (!request_region(smbus->base, smbus->size, nforce2_driver.name)) {
362 		dev_err(&smbus->adapter.dev, "Error requesting region %02x .. %02X for %s\n",
363 			smbus->base, smbus->base+smbus->size-1, name);
364 		return -EBUSY;
365 	}
366 	smbus->adapter.owner = THIS_MODULE;
367 	smbus->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
368 	smbus->adapter.algo = &smbus_algorithm;
369 	smbus->adapter.algo_data = smbus;
370 	smbus->adapter.dev.parent = &dev->dev;
371 	snprintf(smbus->adapter.name, sizeof(smbus->adapter.name),
372 		"SMBus nForce2 adapter at %04x", smbus->base);
373 
374 	error = i2c_add_adapter(&smbus->adapter);
375 	if (error) {
376 		dev_err(&smbus->adapter.dev, "Failed to register adapter.\n");
377 		release_region(smbus->base, smbus->size);
378 		return error;
379 	}
380 	dev_info(&smbus->adapter.dev, "nForce2 SMBus adapter at %#x\n", smbus->base);
381 	return 0;
382 }
383 
384 
385 static int __devinit nforce2_probe(struct pci_dev *dev, const struct pci_device_id *id)
386 {
387 	struct nforce2_smbus *smbuses;
388 	int res1, res2;
389 
390 	/* we support 2 SMBus adapters */
391 	if (!(smbuses = kzalloc(2*sizeof(struct nforce2_smbus), GFP_KERNEL)))
392 		return -ENOMEM;
393 	pci_set_drvdata(dev, smbuses);
394 
395 	switch(dev->device) {
396 	case PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS:
397 	case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS:
398 	case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS:
399 		smbuses[0].blockops = 1;
400 		smbuses[1].blockops = 1;
401 		smbuses[0].can_abort = 1;
402 		smbuses[1].can_abort = 1;
403 	}
404 
405 	/* SMBus adapter 1 */
406 	res1 = nforce2_probe_smb(dev, 4, NFORCE_PCI_SMB1, &smbuses[0], "SMB1");
407 	if (res1 < 0) {
408 		dev_err(&dev->dev, "Error probing SMB1.\n");
409 		smbuses[0].base = 0;	/* to have a check value */
410 	}
411 	/* SMBus adapter 2 */
412 	if (dmi_check_system(nforce2_dmi_blacklist2)) {
413 		dev_err(&dev->dev, "Disabling SMB2 for safety reasons.\n");
414 		res2 = -EPERM;
415 		smbuses[1].base = 0;
416 	} else {
417 		res2 = nforce2_probe_smb(dev, 5, NFORCE_PCI_SMB2, &smbuses[1],
418 					 "SMB2");
419 		if (res2 < 0) {
420 			dev_err(&dev->dev, "Error probing SMB2.\n");
421 			smbuses[1].base = 0;	/* to have a check value */
422 		}
423 	}
424 	if ((res1 < 0) && (res2 < 0)) {
425 		/* we did not find even one of the SMBuses, so we give up */
426 		kfree(smbuses);
427 		return -ENODEV;
428 	}
429 
430 	nforce2_set_reference(&smbuses[0].adapter);
431 	return 0;
432 }
433 
434 
435 static void __devexit nforce2_remove(struct pci_dev *dev)
436 {
437 	struct nforce2_smbus *smbuses = (void*) pci_get_drvdata(dev);
438 
439 	nforce2_set_reference(NULL);
440 	if (smbuses[0].base) {
441 		i2c_del_adapter(&smbuses[0].adapter);
442 		release_region(smbuses[0].base, smbuses[0].size);
443 	}
444 	if (smbuses[1].base) {
445 		i2c_del_adapter(&smbuses[1].adapter);
446 		release_region(smbuses[1].base, smbuses[1].size);
447 	}
448 	kfree(smbuses);
449 }
450 
451 static struct pci_driver nforce2_driver = {
452 	.name		= "nForce2_smbus",
453 	.id_table	= nforce2_ids,
454 	.probe		= nforce2_probe,
455 	.remove		= __devexit_p(nforce2_remove),
456 };
457 
458 static int __init nforce2_init(void)
459 {
460 	return pci_register_driver(&nforce2_driver);
461 }
462 
463 static void __exit nforce2_exit(void)
464 {
465 	pci_unregister_driver(&nforce2_driver);
466 }
467 
468 module_init(nforce2_init);
469 module_exit(nforce2_exit);
470 
471