xref: /openbmc/linux/drivers/i2c/busses/i2c-nforce2.c (revision 1da177e4)
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 
34     This driver supports the 2 SMBuses that are included in the MCP of the
35     nForce2/3/4 chipsets.
36 */
37 
38 /* Note: we assume there can only be one nForce2, with two SMBus interfaces */
39 
40 #include <linux/config.h>
41 #include <linux/module.h>
42 #include <linux/pci.h>
43 #include <linux/kernel.h>
44 #include <linux/stddef.h>
45 #include <linux/sched.h>
46 #include <linux/ioport.h>
47 #include <linux/init.h>
48 #include <linux/i2c.h>
49 #include <linux/delay.h>
50 #include <asm/io.h>
51 
52 MODULE_LICENSE("GPL");
53 MODULE_AUTHOR ("Hans-Frieder Vogt <hfvogt@arcor.de>");
54 MODULE_DESCRIPTION("nForce2 SMBus driver");
55 
56 
57 struct nforce2_smbus {
58 	struct pci_dev *dev;
59 	struct i2c_adapter adapter;
60 	int base;
61 	int size;
62 };
63 
64 
65 /*
66  * nVidia nForce2 SMBus control register definitions
67  */
68 #define NFORCE_PCI_SMB1	0x50
69 #define NFORCE_PCI_SMB2	0x54
70 
71 
72 /*
73  * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
74  */
75 #define NVIDIA_SMB_PRTCL	(smbus->base + 0x00)	/* protocol, PEC */
76 #define NVIDIA_SMB_STS		(smbus->base + 0x01)	/* status */
77 #define NVIDIA_SMB_ADDR		(smbus->base + 0x02)	/* address */
78 #define NVIDIA_SMB_CMD		(smbus->base + 0x03)	/* command */
79 #define NVIDIA_SMB_DATA		(smbus->base + 0x04)	/* 32 data registers */
80 #define NVIDIA_SMB_BCNT		(smbus->base + 0x24)	/* number of data bytes */
81 #define NVIDIA_SMB_ALRM_A	(smbus->base + 0x25)	/* alarm address */
82 #define NVIDIA_SMB_ALRM_D	(smbus->base + 0x26)	/* 2 bytes alarm data */
83 
84 #define NVIDIA_SMB_STS_DONE	0x80
85 #define NVIDIA_SMB_STS_ALRM	0x40
86 #define NVIDIA_SMB_STS_RES	0x20
87 #define NVIDIA_SMB_STS_STATUS	0x1f
88 
89 #define NVIDIA_SMB_PRTCL_WRITE			0x00
90 #define NVIDIA_SMB_PRTCL_READ			0x01
91 #define NVIDIA_SMB_PRTCL_QUICK			0x02
92 #define NVIDIA_SMB_PRTCL_BYTE			0x04
93 #define NVIDIA_SMB_PRTCL_BYTE_DATA		0x06
94 #define NVIDIA_SMB_PRTCL_WORD_DATA		0x08
95 #define NVIDIA_SMB_PRTCL_BLOCK_DATA		0x0a
96 #define NVIDIA_SMB_PRTCL_PROC_CALL		0x0c
97 #define NVIDIA_SMB_PRTCL_BLOCK_PROC_CALL	0x0d
98 #define NVIDIA_SMB_PRTCL_I2C_BLOCK_DATA		0x4a
99 #define NVIDIA_SMB_PRTCL_PEC			0x80
100 
101 
102 /* Other settings */
103 #define MAX_TIMEOUT 256
104 
105 
106 
107 static s32 nforce2_access(struct i2c_adapter *adap, u16 addr,
108 		       unsigned short flags, char read_write,
109 		       u8 command, int size, union i2c_smbus_data *data);
110 static u32 nforce2_func(struct i2c_adapter *adapter);
111 
112 
113 static struct i2c_algorithm smbus_algorithm = {
114 	.name = "Non-I2C SMBus adapter",
115 	.id = I2C_ALGO_SMBUS,
116 	.smbus_xfer = nforce2_access,
117 	.functionality = nforce2_func,
118 };
119 
120 static struct i2c_adapter nforce2_adapter = {
121 	.owner          = THIS_MODULE,
122 	.class          = I2C_CLASS_HWMON,
123 	.algo           = &smbus_algorithm,
124 	.name   	= "unset",
125 };
126 
127 /* Return -1 on error. See smbus.h for more information */
128 static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
129 		unsigned short flags, char read_write,
130 		u8 command, int size, union i2c_smbus_data * data)
131 {
132 	struct nforce2_smbus *smbus = adap->algo_data;
133 	unsigned char protocol, pec, temp;
134 	unsigned char len = 0; /* to keep the compiler quiet */
135 	int timeout = 0;
136 	int i;
137 
138 	protocol = (read_write == I2C_SMBUS_READ) ? NVIDIA_SMB_PRTCL_READ :
139 		NVIDIA_SMB_PRTCL_WRITE;
140 	pec = (flags & I2C_CLIENT_PEC) ? NVIDIA_SMB_PRTCL_PEC : 0;
141 
142 	switch (size) {
143 
144 		case I2C_SMBUS_QUICK:
145 			protocol |= NVIDIA_SMB_PRTCL_QUICK;
146 			read_write = I2C_SMBUS_WRITE;
147 			break;
148 
149 		case I2C_SMBUS_BYTE:
150 			if (read_write == I2C_SMBUS_WRITE)
151 				outb_p(command, NVIDIA_SMB_CMD);
152 			protocol |= NVIDIA_SMB_PRTCL_BYTE;
153 			break;
154 
155 		case I2C_SMBUS_BYTE_DATA:
156 			outb_p(command, NVIDIA_SMB_CMD);
157 			if (read_write == I2C_SMBUS_WRITE)
158 				outb_p(data->byte, NVIDIA_SMB_DATA);
159 			protocol |= NVIDIA_SMB_PRTCL_BYTE_DATA;
160 			break;
161 
162 		case I2C_SMBUS_WORD_DATA:
163 			outb_p(command, NVIDIA_SMB_CMD);
164 			if (read_write == I2C_SMBUS_WRITE) {
165 				 outb_p(data->word, NVIDIA_SMB_DATA);
166 				 outb_p(data->word >> 8, NVIDIA_SMB_DATA+1);
167 			}
168 			protocol |= NVIDIA_SMB_PRTCL_WORD_DATA | pec;
169 			break;
170 
171 		case I2C_SMBUS_BLOCK_DATA:
172 			outb_p(command, NVIDIA_SMB_CMD);
173 			if (read_write == I2C_SMBUS_WRITE) {
174 				len = min_t(u8, data->block[0], 32);
175 				outb_p(len, NVIDIA_SMB_BCNT);
176 				for (i = 0; i < len; i++)
177 					outb_p(data->block[i + 1], NVIDIA_SMB_DATA+i);
178 			}
179 			protocol |= NVIDIA_SMB_PRTCL_BLOCK_DATA | pec;
180 			break;
181 
182 		case I2C_SMBUS_I2C_BLOCK_DATA:
183 			len = min_t(u8, data->block[0], 32);
184 			outb_p(command, NVIDIA_SMB_CMD);
185 			outb_p(len, NVIDIA_SMB_BCNT);
186 			if (read_write == I2C_SMBUS_WRITE)
187 				for (i = 0; i < len; i++)
188 					outb_p(data->block[i + 1], NVIDIA_SMB_DATA+i);
189 			protocol |= NVIDIA_SMB_PRTCL_I2C_BLOCK_DATA;
190 			break;
191 
192 		case I2C_SMBUS_PROC_CALL:
193 			dev_err(&adap->dev, "I2C_SMBUS_PROC_CALL not supported!\n");
194 			return -1;
195 			/*
196 			outb_p(command, NVIDIA_SMB_CMD);
197 			outb_p(data->word, NVIDIA_SMB_DATA);
198 			outb_p(data->word >> 8, NVIDIA_SMB_DATA + 1);
199 			protocol = NVIDIA_SMB_PRTCL_PROC_CALL | pec;
200 			read_write = I2C_SMBUS_READ;
201 			break;
202 			 */
203 
204 		case I2C_SMBUS_BLOCK_PROC_CALL:
205 			dev_err(&adap->dev, "I2C_SMBUS_BLOCK_PROC_CALL not supported!\n");
206 			return -1;
207 			/*
208 			protocol |= pec;
209 			len = min_t(u8, data->block[0], 31);
210 			outb_p(command, NVIDIA_SMB_CMD);
211 			outb_p(len, NVIDIA_SMB_BCNT);
212 			for (i = 0; i < len; i++)
213 				outb_p(data->block[i + 1], NVIDIA_SMB_DATA + i);
214 			protocol = NVIDIA_SMB_PRTCL_BLOCK_PROC_CALL | pec;
215 			read_write = I2C_SMBUS_READ;
216 			break;
217 			*/
218 
219 		case I2C_SMBUS_WORD_DATA_PEC:
220 		case I2C_SMBUS_BLOCK_DATA_PEC:
221 		case I2C_SMBUS_PROC_CALL_PEC:
222 		case I2C_SMBUS_BLOCK_PROC_CALL_PEC:
223 			dev_err(&adap->dev, "Unexpected software PEC transaction %d\n.", size);
224 			return -1;
225 
226 		default:
227 			dev_err(&adap->dev, "Unsupported transaction %d\n", size);
228 			return -1;
229 	}
230 
231 	outb_p((addr & 0x7f) << 1, NVIDIA_SMB_ADDR);
232 	outb_p(protocol, NVIDIA_SMB_PRTCL);
233 
234 	temp = inb_p(NVIDIA_SMB_STS);
235 
236 #if 0
237 	do {
238 		i2c_do_pause(1);
239 		temp = inb_p(NVIDIA_SMB_STS);
240 	} while (((temp & NVIDIA_SMB_STS_DONE) == 0) && (timeout++ < MAX_TIMEOUT));
241 #endif
242 	if (~temp & NVIDIA_SMB_STS_DONE) {
243 		udelay(500);
244 		temp = inb_p(NVIDIA_SMB_STS);
245 	}
246 	if (~temp & NVIDIA_SMB_STS_DONE) {
247 		msleep(10);
248 		temp = inb_p(NVIDIA_SMB_STS);
249 	}
250 
251 	if ((timeout >= MAX_TIMEOUT) || (~temp & NVIDIA_SMB_STS_DONE)
252 		|| (temp & NVIDIA_SMB_STS_STATUS))
253 		return -1;
254 
255 	if (read_write == I2C_SMBUS_WRITE)
256 		return 0;
257 
258 	switch (size) {
259 
260 		case I2C_SMBUS_BYTE:
261 		case I2C_SMBUS_BYTE_DATA:
262 			data->byte = inb_p(NVIDIA_SMB_DATA);
263 			break;
264 
265 		case I2C_SMBUS_WORD_DATA:
266 		/* case I2C_SMBUS_PROC_CALL: not supported */
267 			data->word = inb_p(NVIDIA_SMB_DATA) | (inb_p(NVIDIA_SMB_DATA+1) << 8);
268 			break;
269 
270 		case I2C_SMBUS_BLOCK_DATA:
271 		/* case I2C_SMBUS_BLOCK_PROC_CALL: not supported */
272 			len = inb_p(NVIDIA_SMB_BCNT);
273 			len = min_t(u8, len, 32);
274 		case I2C_SMBUS_I2C_BLOCK_DATA:
275 			for (i = 0; i < len; i++)
276 				data->block[i+1] = inb_p(NVIDIA_SMB_DATA + i);
277 			data->block[0] = len;
278 			break;
279 	}
280 
281 	return 0;
282 }
283 
284 
285 static u32 nforce2_func(struct i2c_adapter *adapter)
286 {
287 	/* other functionality might be possible, but is not tested */
288 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
289 	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA /* |
290 	    I2C_FUNC_SMBUS_BLOCK_DATA */;
291 }
292 
293 
294 static struct pci_device_id nforce2_ids[] = {
295 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS) },
296 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2S_SMBUS) },
297 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3_SMBUS) },
298 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3S_SMBUS) },
299 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE4_SMBUS) },
300 	{ 0 }
301 };
302 
303 
304 MODULE_DEVICE_TABLE (pci, nforce2_ids);
305 
306 
307 static int __devinit nforce2_probe_smb (struct pci_dev *dev, int reg,
308 	struct nforce2_smbus *smbus, char *name)
309 {
310 	u16 iobase;
311 	int error;
312 
313 	if (pci_read_config_word(dev, reg, &iobase) != PCIBIOS_SUCCESSFUL) {
314 		dev_err(&smbus->adapter.dev, "Error reading PCI config for %s\n", name);
315 		return -1;
316 	}
317 	smbus->dev  = dev;
318 	smbus->base = iobase & 0xfffc;
319 	smbus->size = 8;
320 
321 	if (!request_region(smbus->base, smbus->size, "nForce2 SMBus")) {
322 		dev_err(&smbus->adapter.dev, "Error requesting region %02x .. %02X for %s\n",
323 			smbus->base, smbus->base+smbus->size-1, name);
324 		return -1;
325 	}
326 	smbus->adapter = nforce2_adapter;
327 	smbus->adapter.algo_data = smbus;
328 	smbus->adapter.dev.parent = &dev->dev;
329 	snprintf(smbus->adapter.name, I2C_NAME_SIZE,
330 		"SMBus nForce2 adapter at %04x", smbus->base);
331 
332 	error = i2c_add_adapter(&smbus->adapter);
333 	if (error) {
334 		dev_err(&smbus->adapter.dev, "Failed to register adapter.\n");
335 		release_region(smbus->base, smbus->size);
336 		return -1;
337 	}
338 	dev_info(&smbus->adapter.dev, "nForce2 SMBus adapter at %#x\n", smbus->base);
339 	return 0;
340 }
341 
342 
343 static int __devinit nforce2_probe(struct pci_dev *dev, const struct pci_device_id *id)
344 {
345 	struct nforce2_smbus *smbuses;
346 	int res1, res2;
347 
348 	/* we support 2 SMBus adapters */
349 	if (!(smbuses = (void *)kmalloc(2*sizeof(struct nforce2_smbus),
350 				       	GFP_KERNEL)))
351 		return -ENOMEM;
352 	memset (smbuses, 0, 2*sizeof(struct nforce2_smbus));
353 	pci_set_drvdata(dev, smbuses);
354 
355 	/* SMBus adapter 1 */
356 	res1 = nforce2_probe_smb (dev, NFORCE_PCI_SMB1, &smbuses[0], "SMB1");
357 	if (res1 < 0) {
358 		dev_err(&dev->dev, "Error probing SMB1.\n");
359 		smbuses[0].base = 0;	/* to have a check value */
360 	}
361 	res2 = nforce2_probe_smb (dev, NFORCE_PCI_SMB2, &smbuses[1], "SMB2");
362 	if (res2 < 0) {
363 		dev_err(&dev->dev, "Error probing SMB2.\n");
364 		smbuses[1].base = 0;	/* to have a check value */
365 	}
366 	if ((res1 < 0) && (res2 < 0)) {
367 		/* we did not find even one of the SMBuses, so we give up */
368 		kfree(smbuses);
369 		return -ENODEV;
370 	}
371 
372 	return 0;
373 }
374 
375 
376 static void __devexit nforce2_remove(struct pci_dev *dev)
377 {
378 	struct nforce2_smbus *smbuses = (void*) pci_get_drvdata(dev);
379 
380 	if (smbuses[0].base) {
381 		i2c_del_adapter(&smbuses[0].adapter);
382 		release_region(smbuses[0].base, smbuses[0].size);
383 	}
384 	if (smbuses[1].base) {
385 		i2c_del_adapter(&smbuses[1].adapter);
386 		release_region(smbuses[1].base, smbuses[1].size);
387 	}
388 	kfree(smbuses);
389 }
390 
391 static struct pci_driver nforce2_driver = {
392 	.name		= "nForce2_smbus",
393 	.id_table	= nforce2_ids,
394 	.probe		= nforce2_probe,
395 	.remove		= __devexit_p(nforce2_remove),
396 };
397 
398 static int __init nforce2_init(void)
399 {
400 	return pci_register_driver(&nforce2_driver);
401 }
402 
403 static void __exit nforce2_exit(void)
404 {
405 	pci_unregister_driver(&nforce2_driver);
406 }
407 
408 module_init(nforce2_init);
409 module_exit(nforce2_exit);
410 
411