Free Electrons

Embedded Linux Experts

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
/*
    SMBus driver for nVidia nForce2 MCP

    Added nForce3 Pro 150  Thomas Leibold <thomas@plx.com>,
	Ported to 2.5 Patrick Dreker <patrick@dreker.de>,
    Copyright (c) 2003  Hans-Frieder Vogt <hfvogt@arcor.de>,
    Based on
    SMBus 2.0 driver for AMD-8111 IO-Hub
    Copyright (c) 2002 Vojtech Pavlik

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/*
    SUPPORTED DEVICES		PCI ID
    nForce2 MCP			0064
    nForce2 Ultra 400 MCP	0084
    nForce3 Pro150 MCP		00D4
    nForce3 250Gb MCP		00E4
    nForce4 MCP			0052
    nForce4 MCP-04		0034
    nForce MCP51		0264
    nForce MCP55		0368
    nForce MCP61		03EB
    nForce MCP65		0446
    nForce MCP67		0542
    nForce MCP73		07D8
    nForce MCP78S		0752
    nForce MCP79		0AA2

    This driver supports the 2 SMBuses that are included in the MCP of the
    nForce2/3/4/5xx chipsets.
*/

/* Note: we assume there can only be one nForce2, with two SMBus interfaces */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/io.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR ("Hans-Frieder Vogt <hfvogt@gmx.net>");
MODULE_DESCRIPTION("nForce2/3/4/5xx SMBus driver");


struct nforce2_smbus {
	struct i2c_adapter adapter;
	int base;
	int size;
	int blockops;
	int can_abort;
};


/*
 * nVidia nForce2 SMBus control register definitions
 * (Newer incarnations use standard BARs 4 and 5 instead)
 */
#define NFORCE_PCI_SMB1	0x50
#define NFORCE_PCI_SMB2	0x54


/*
 * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
 */
#define NVIDIA_SMB_PRTCL	(smbus->base + 0x00)	/* protocol, PEC */
#define NVIDIA_SMB_STS		(smbus->base + 0x01)	/* status */
#define NVIDIA_SMB_ADDR		(smbus->base + 0x02)	/* address */
#define NVIDIA_SMB_CMD		(smbus->base + 0x03)	/* command */
#define NVIDIA_SMB_DATA		(smbus->base + 0x04)	/* 32 data registers */
#define NVIDIA_SMB_BCNT		(smbus->base + 0x24)	/* number of data
							   bytes */
#define NVIDIA_SMB_STATUS_ABRT	(smbus->base + 0x3c)	/* register used to
							   check the status of
							   the abort command */
#define NVIDIA_SMB_CTRL		(smbus->base + 0x3e)	/* control register */

#define NVIDIA_SMB_STATUS_ABRT_STS	0x01		/* Bit to notify that
							   abort succeeded */
#define NVIDIA_SMB_CTRL_ABORT	0x20
#define NVIDIA_SMB_STS_DONE	0x80
#define NVIDIA_SMB_STS_ALRM	0x40
#define NVIDIA_SMB_STS_RES	0x20
#define NVIDIA_SMB_STS_STATUS	0x1f

#define NVIDIA_SMB_PRTCL_WRITE			0x00
#define NVIDIA_SMB_PRTCL_READ			0x01
#define NVIDIA_SMB_PRTCL_QUICK			0x02
#define NVIDIA_SMB_PRTCL_BYTE			0x04
#define NVIDIA_SMB_PRTCL_BYTE_DATA		0x06
#define NVIDIA_SMB_PRTCL_WORD_DATA		0x08
#define NVIDIA_SMB_PRTCL_BLOCK_DATA		0x0a
#define NVIDIA_SMB_PRTCL_PEC			0x80

/* Misc definitions */
#define MAX_TIMEOUT	100

/* We disable the second SMBus channel on these boards */
static struct dmi_system_id __devinitdata nforce2_dmi_blacklist2[] = {
	{
		.ident = "DFI Lanparty NF4 Expert",
		.matches = {
			DMI_MATCH(DMI_BOARD_VENDOR, "DFI Corp,LTD"),
			DMI_MATCH(DMI_BOARD_NAME, "LP UT NF4 Expert"),
		},
	},
	{ }
};

static struct pci_driver nforce2_driver;

/* For multiplexing support, we need a global reference to the 1st
   SMBus channel */
#if defined CONFIG_I2C_NFORCE2_S4985 || defined CONFIG_I2C_NFORCE2_S4985_MODULE
struct i2c_adapter *nforce2_smbus;
EXPORT_SYMBOL_GPL(nforce2_smbus);

static void nforce2_set_reference(struct i2c_adapter *adap)
{
	nforce2_smbus = adap;
}
#else
static inline void nforce2_set_reference(struct i2c_adapter *adap) { }
#endif

static void nforce2_abort(struct i2c_adapter *adap)
{
	struct nforce2_smbus *smbus = adap->algo_data;
	int timeout = 0;
	unsigned char temp;

	dev_dbg(&adap->dev, "Aborting current transaction\n");

	outb_p(NVIDIA_SMB_CTRL_ABORT, NVIDIA_SMB_CTRL);
	do {
		msleep(1);
		temp = inb_p(NVIDIA_SMB_STATUS_ABRT);
	} while (!(temp & NVIDIA_SMB_STATUS_ABRT_STS) &&
			(timeout++ < MAX_TIMEOUT));
	if (!(temp & NVIDIA_SMB_STATUS_ABRT_STS))
		dev_err(&adap->dev, "Can't reset the smbus\n");
	outb_p(NVIDIA_SMB_STATUS_ABRT_STS, NVIDIA_SMB_STATUS_ABRT);
}

static int nforce2_check_status(struct i2c_adapter *adap)
{
	struct nforce2_smbus *smbus = adap->algo_data;
	int timeout = 0;
	unsigned char temp;

	do {
		msleep(1);
		temp = inb_p(NVIDIA_SMB_STS);
	} while ((!temp) && (timeout++ < MAX_TIMEOUT));

	if (timeout > MAX_TIMEOUT) {
		dev_dbg(&adap->dev, "SMBus Timeout!\n");
		if (smbus->can_abort)
			nforce2_abort(adap);
		return -ETIMEDOUT;
	}
	if (!(temp & NVIDIA_SMB_STS_DONE) || (temp & NVIDIA_SMB_STS_STATUS)) {
		dev_dbg(&adap->dev, "Transaction failed (0x%02x)!\n", temp);
		return -EIO;
	}
	return 0;
}

/* Return negative errno on error */
static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
		unsigned short flags, char read_write,
		u8 command, int size, union i2c_smbus_data * data)
{
	struct nforce2_smbus *smbus = adap->algo_data;
	unsigned char protocol, pec;
	u8 len;
	int i, status;

	protocol = (read_write == I2C_SMBUS_READ) ? NVIDIA_SMB_PRTCL_READ :
		NVIDIA_SMB_PRTCL_WRITE;
	pec = (flags & I2C_CLIENT_PEC) ? NVIDIA_SMB_PRTCL_PEC : 0;

	switch (size) {

		case I2C_SMBUS_QUICK:
			protocol |= NVIDIA_SMB_PRTCL_QUICK;
			read_write = I2C_SMBUS_WRITE;
			break;

		case I2C_SMBUS_BYTE:
			if (read_write == I2C_SMBUS_WRITE)
				outb_p(command, NVIDIA_SMB_CMD);
			protocol |= NVIDIA_SMB_PRTCL_BYTE;
			break;

		case I2C_SMBUS_BYTE_DATA:
			outb_p(command, NVIDIA_SMB_CMD);
			if (read_write == I2C_SMBUS_WRITE)
				outb_p(data->byte, NVIDIA_SMB_DATA);
			protocol |= NVIDIA_SMB_PRTCL_BYTE_DATA;
			break;

		case I2C_SMBUS_WORD_DATA:
			outb_p(command, NVIDIA_SMB_CMD);
			if (read_write == I2C_SMBUS_WRITE) {
				 outb_p(data->word, NVIDIA_SMB_DATA);
				 outb_p(data->word >> 8, NVIDIA_SMB_DATA+1);
			}
			protocol |= NVIDIA_SMB_PRTCL_WORD_DATA | pec;
			break;

		case I2C_SMBUS_BLOCK_DATA:
			outb_p(command, NVIDIA_SMB_CMD);
			if (read_write == I2C_SMBUS_WRITE) {
				len = data->block[0];
				if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
					dev_err(&adap->dev,
						"Transaction failed "
						"(requested block size: %d)\n",
						len);
					return -EINVAL;
				}
				outb_p(len, NVIDIA_SMB_BCNT);
				for (i = 0; i < I2C_SMBUS_BLOCK_MAX; i++)
					outb_p(data->block[i + 1],
					       NVIDIA_SMB_DATA+i);
			}
			protocol |= NVIDIA_SMB_PRTCL_BLOCK_DATA | pec;
			break;

		default:
			dev_err(&adap->dev, "Unsupported transaction %d\n", size);
			return -EOPNOTSUPP;
	}

	outb_p((addr & 0x7f) << 1, NVIDIA_SMB_ADDR);
	outb_p(protocol, NVIDIA_SMB_PRTCL);

	status = nforce2_check_status(adap);
	if (status)
		return status;

	if (read_write == I2C_SMBUS_WRITE)
		return 0;

	switch (size) {

		case I2C_SMBUS_BYTE:
		case I2C_SMBUS_BYTE_DATA:
			data->byte = inb_p(NVIDIA_SMB_DATA);
			break;

		case I2C_SMBUS_WORD_DATA:
			data->word = inb_p(NVIDIA_SMB_DATA) | (inb_p(NVIDIA_SMB_DATA+1) << 8);
			break;

		case I2C_SMBUS_BLOCK_DATA:
			len = inb_p(NVIDIA_SMB_BCNT);
			if ((len <= 0) || (len > I2C_SMBUS_BLOCK_MAX)) {
				dev_err(&adap->dev, "Transaction failed "
					"(received block size: 0x%02x)\n",
					len);
				return -EPROTO;
			}
			for (i = 0; i < len; i++)
				data->block[i+1] = inb_p(NVIDIA_SMB_DATA + i);
			data->block[0] = len;
			break;
	}

	return 0;
}


static u32 nforce2_func(struct i2c_adapter *adapter)
{
	/* other functionality might be possible, but is not tested */
	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
	       I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
	       I2C_FUNC_SMBUS_PEC |
	       (((struct nforce2_smbus*)adapter->algo_data)->blockops ?
		I2C_FUNC_SMBUS_BLOCK_DATA : 0);
}

static struct i2c_algorithm smbus_algorithm = {
	.smbus_xfer	= nforce2_access,
	.functionality	= nforce2_func,
};


static DEFINE_PCI_DEVICE_TABLE(nforce2_ids) = {
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2S_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3S_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE4_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP04_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP65_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP67_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP73_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP78S_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP79_SMBUS) },
	{ 0 }
};

MODULE_DEVICE_TABLE (pci, nforce2_ids);


static int __devinit nforce2_probe_smb (struct pci_dev *dev, int bar,
	int alt_reg, struct nforce2_smbus *smbus, const char *name)
{
	int error;

	smbus->base = pci_resource_start(dev, bar);
	if (smbus->base) {
		smbus->size = pci_resource_len(dev, bar);
	} else {
		/* Older incarnations of the device used non-standard BARs */
		u16 iobase;

		if (pci_read_config_word(dev, alt_reg, &iobase)
		    != PCIBIOS_SUCCESSFUL) {
			dev_err(&dev->dev, "Error reading PCI config for %s\n",
				name);
			return -EIO;
		}

		smbus->base = iobase & PCI_BASE_ADDRESS_IO_MASK;
		smbus->size = 64;
	}

	error = acpi_check_region(smbus->base, smbus->size,
				  nforce2_driver.name);
	if (error)
		return error;

	if (!request_region(smbus->base, smbus->size, nforce2_driver.name)) {
		dev_err(&smbus->adapter.dev, "Error requesting region %02x .. %02X for %s\n",
			smbus->base, smbus->base+smbus->size-1, name);
		return -EBUSY;
	}
	smbus->adapter.owner = THIS_MODULE;
	smbus->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
	smbus->adapter.algo = &smbus_algorithm;
	smbus->adapter.algo_data = smbus;
	smbus->adapter.dev.parent = &dev->dev;
	snprintf(smbus->adapter.name, sizeof(smbus->adapter.name),
		"SMBus nForce2 adapter at %04x", smbus->base);

	error = i2c_add_adapter(&smbus->adapter);
	if (error) {
		dev_err(&smbus->adapter.dev, "Failed to register adapter.\n");
		release_region(smbus->base, smbus->size);
		return error;
	}
	dev_info(&smbus->adapter.dev, "nForce2 SMBus adapter at %#x\n", smbus->base);
	return 0;
}


static int __devinit nforce2_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	struct nforce2_smbus *smbuses;
	int res1, res2;

	/* we support 2 SMBus adapters */
	if (!(smbuses = kzalloc(2*sizeof(struct nforce2_smbus), GFP_KERNEL)))
		return -ENOMEM;
	pci_set_drvdata(dev, smbuses);

	switch(dev->device) {
	case PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS:
	case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS:
	case PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS:
		smbuses[0].blockops = 1;
		smbuses[1].blockops = 1;
		smbuses[0].can_abort = 1;
		smbuses[1].can_abort = 1;
	}

	/* SMBus adapter 1 */
	res1 = nforce2_probe_smb(dev, 4, NFORCE_PCI_SMB1, &smbuses[0], "SMB1");
	if (res1 < 0)
		smbuses[0].base = 0;	/* to have a check value */

	/* SMBus adapter 2 */
	if (dmi_check_system(nforce2_dmi_blacklist2)) {
		dev_err(&dev->dev, "Disabling SMB2 for safety reasons.\n");
		res2 = -EPERM;
		smbuses[1].base = 0;
	} else {
		res2 = nforce2_probe_smb(dev, 5, NFORCE_PCI_SMB2, &smbuses[1],
					 "SMB2");
		if (res2 < 0)
			smbuses[1].base = 0;	/* to have a check value */
	}

	if ((res1 < 0) && (res2 < 0)) {
		/* we did not find even one of the SMBuses, so we give up */
		kfree(smbuses);
		return -ENODEV;
	}

	nforce2_set_reference(&smbuses[0].adapter);
	return 0;
}


static void __devexit nforce2_remove(struct pci_dev *dev)
{
	struct nforce2_smbus *smbuses = pci_get_drvdata(dev);

	nforce2_set_reference(NULL);
	if (smbuses[0].base) {
		i2c_del_adapter(&smbuses[0].adapter);
		release_region(smbuses[0].base, smbuses[0].size);
	}
	if (smbuses[1].base) {
		i2c_del_adapter(&smbuses[1].adapter);
		release_region(smbuses[1].base, smbuses[1].size);
	}
	kfree(smbuses);
}

static struct pci_driver nforce2_driver = {
	.name		= "nForce2_smbus",
	.id_table	= nforce2_ids,
	.probe		= nforce2_probe,
	.remove		= __devexit_p(nforce2_remove),
};

static int __init nforce2_init(void)
{
	return pci_register_driver(&nforce2_driver);
}

static void __exit nforce2_exit(void)
{
	pci_unregister_driver(&nforce2_driver);
}

module_init(nforce2_init);
module_exit(nforce2_exit);