xref: /openbmc/linux/drivers/i2c/busses/i2c-nforce2.c (revision 64c70b1c)
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     nForce4 MCP51		0264
35     nForce4 MCP55		0368
36     nForce MCP61		03EB
37     nForce MCP65		0446
38 
39     This driver supports the 2 SMBuses that are included in the MCP of the
40     nForce2/3/4/5xx chipsets.
41 */
42 
43 /* Note: we assume there can only be one nForce2, with two SMBus interfaces */
44 
45 #include <linux/module.h>
46 #include <linux/pci.h>
47 #include <linux/kernel.h>
48 #include <linux/stddef.h>
49 #include <linux/ioport.h>
50 #include <linux/init.h>
51 #include <linux/i2c.h>
52 #include <linux/delay.h>
53 #include <asm/io.h>
54 
55 MODULE_LICENSE("GPL");
56 MODULE_AUTHOR ("Hans-Frieder Vogt <hfvogt@gmx.net>");
57 MODULE_DESCRIPTION("nForce2/3/4/5xx SMBus driver");
58 
59 
60 struct nforce2_smbus {
61 	struct i2c_adapter adapter;
62 	int base;
63 	int size;
64 };
65 
66 
67 /*
68  * nVidia nForce2 SMBus control register definitions
69  * (Newer incarnations use standard BARs 4 and 5 instead)
70  */
71 #define NFORCE_PCI_SMB1	0x50
72 #define NFORCE_PCI_SMB2	0x54
73 
74 
75 /*
76  * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
77  */
78 #define NVIDIA_SMB_PRTCL	(smbus->base + 0x00)	/* protocol, PEC */
79 #define NVIDIA_SMB_STS		(smbus->base + 0x01)	/* status */
80 #define NVIDIA_SMB_ADDR		(smbus->base + 0x02)	/* address */
81 #define NVIDIA_SMB_CMD		(smbus->base + 0x03)	/* command */
82 #define NVIDIA_SMB_DATA		(smbus->base + 0x04)	/* 32 data registers */
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_PEC			0x80
96 
97 static struct pci_driver nforce2_driver;
98 
99 /* Return -1 on error */
100 static s32 nforce2_access(struct i2c_adapter * adap, u16 addr,
101 		unsigned short flags, char read_write,
102 		u8 command, int size, union i2c_smbus_data * data)
103 {
104 	struct nforce2_smbus *smbus = adap->algo_data;
105 	unsigned char protocol, pec, temp;
106 
107 	protocol = (read_write == I2C_SMBUS_READ) ? NVIDIA_SMB_PRTCL_READ :
108 		NVIDIA_SMB_PRTCL_WRITE;
109 	pec = (flags & I2C_CLIENT_PEC) ? NVIDIA_SMB_PRTCL_PEC : 0;
110 
111 	switch (size) {
112 
113 		case I2C_SMBUS_QUICK:
114 			protocol |= NVIDIA_SMB_PRTCL_QUICK;
115 			read_write = I2C_SMBUS_WRITE;
116 			break;
117 
118 		case I2C_SMBUS_BYTE:
119 			if (read_write == I2C_SMBUS_WRITE)
120 				outb_p(command, NVIDIA_SMB_CMD);
121 			protocol |= NVIDIA_SMB_PRTCL_BYTE;
122 			break;
123 
124 		case I2C_SMBUS_BYTE_DATA:
125 			outb_p(command, NVIDIA_SMB_CMD);
126 			if (read_write == I2C_SMBUS_WRITE)
127 				outb_p(data->byte, NVIDIA_SMB_DATA);
128 			protocol |= NVIDIA_SMB_PRTCL_BYTE_DATA;
129 			break;
130 
131 		case I2C_SMBUS_WORD_DATA:
132 			outb_p(command, NVIDIA_SMB_CMD);
133 			if (read_write == I2C_SMBUS_WRITE) {
134 				 outb_p(data->word, NVIDIA_SMB_DATA);
135 				 outb_p(data->word >> 8, NVIDIA_SMB_DATA+1);
136 			}
137 			protocol |= NVIDIA_SMB_PRTCL_WORD_DATA | pec;
138 			break;
139 
140 		default:
141 			dev_err(&adap->dev, "Unsupported transaction %d\n", size);
142 			return -1;
143 	}
144 
145 	outb_p((addr & 0x7f) << 1, NVIDIA_SMB_ADDR);
146 	outb_p(protocol, NVIDIA_SMB_PRTCL);
147 
148 	temp = inb_p(NVIDIA_SMB_STS);
149 
150 	if (~temp & NVIDIA_SMB_STS_DONE) {
151 		udelay(500);
152 		temp = inb_p(NVIDIA_SMB_STS);
153 	}
154 	if (~temp & NVIDIA_SMB_STS_DONE) {
155 		msleep(10);
156 		temp = inb_p(NVIDIA_SMB_STS);
157 	}
158 
159 	if ((~temp & NVIDIA_SMB_STS_DONE) || (temp & NVIDIA_SMB_STS_STATUS)) {
160 		dev_dbg(&adap->dev, "SMBus Timeout! (0x%02x)\n", temp);
161 		return -1;
162 	}
163 
164 	if (read_write == I2C_SMBUS_WRITE)
165 		return 0;
166 
167 	switch (size) {
168 
169 		case I2C_SMBUS_BYTE:
170 		case I2C_SMBUS_BYTE_DATA:
171 			data->byte = inb_p(NVIDIA_SMB_DATA);
172 			break;
173 
174 		case I2C_SMBUS_WORD_DATA:
175 			data->word = inb_p(NVIDIA_SMB_DATA) | (inb_p(NVIDIA_SMB_DATA+1) << 8);
176 			break;
177 	}
178 
179 	return 0;
180 }
181 
182 
183 static u32 nforce2_func(struct i2c_adapter *adapter)
184 {
185 	/* other functionality might be possible, but is not tested */
186 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
187 	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA;
188 }
189 
190 static struct i2c_algorithm smbus_algorithm = {
191 	.smbus_xfer	= nforce2_access,
192 	.functionality	= nforce2_func,
193 };
194 
195 
196 static struct pci_device_id nforce2_ids[] = {
197 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS) },
198 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE2S_SMBUS) },
199 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3_SMBUS) },
200 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE3S_SMBUS) },
201 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE4_SMBUS) },
202 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP04_SMBUS) },
203 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS) },
204 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS) },
205 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP61_SMBUS) },
206 	{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP65_SMBUS) },
207 	{ 0 }
208 };
209 
210 MODULE_DEVICE_TABLE (pci, nforce2_ids);
211 
212 
213 static int __devinit nforce2_probe_smb (struct pci_dev *dev, int bar,
214 	int alt_reg, struct nforce2_smbus *smbus, const char *name)
215 {
216 	int error;
217 
218 	smbus->base = pci_resource_start(dev, bar);
219 	if (smbus->base) {
220 		smbus->size = pci_resource_len(dev, bar);
221 	} else {
222 		/* Older incarnations of the device used non-standard BARs */
223 		u16 iobase;
224 
225 		if (pci_read_config_word(dev, alt_reg, &iobase)
226 		    != PCIBIOS_SUCCESSFUL) {
227 			dev_err(&dev->dev, "Error reading PCI config for %s\n",
228 				name);
229 			return -1;
230 		}
231 
232 		smbus->base = iobase & PCI_BASE_ADDRESS_IO_MASK;
233 		smbus->size = 64;
234 	}
235 
236 	if (!request_region(smbus->base, smbus->size, nforce2_driver.name)) {
237 		dev_err(&smbus->adapter.dev, "Error requesting region %02x .. %02X for %s\n",
238 			smbus->base, smbus->base+smbus->size-1, name);
239 		return -1;
240 	}
241 	smbus->adapter.owner = THIS_MODULE;
242 	smbus->adapter.id = I2C_HW_SMBUS_NFORCE2;
243 	smbus->adapter.class = I2C_CLASS_HWMON;
244 	smbus->adapter.algo = &smbus_algorithm;
245 	smbus->adapter.algo_data = smbus;
246 	smbus->adapter.dev.parent = &dev->dev;
247 	snprintf(smbus->adapter.name, sizeof(smbus->adapter.name),
248 		"SMBus nForce2 adapter at %04x", smbus->base);
249 
250 	error = i2c_add_adapter(&smbus->adapter);
251 	if (error) {
252 		dev_err(&smbus->adapter.dev, "Failed to register adapter.\n");
253 		release_region(smbus->base, smbus->size);
254 		return -1;
255 	}
256 	dev_info(&smbus->adapter.dev, "nForce2 SMBus adapter at %#x\n", smbus->base);
257 	return 0;
258 }
259 
260 
261 static int __devinit nforce2_probe(struct pci_dev *dev, const struct pci_device_id *id)
262 {
263 	struct nforce2_smbus *smbuses;
264 	int res1, res2;
265 
266 	/* we support 2 SMBus adapters */
267 	if (!(smbuses = kzalloc(2*sizeof(struct nforce2_smbus), GFP_KERNEL)))
268 		return -ENOMEM;
269 	pci_set_drvdata(dev, smbuses);
270 
271 	/* SMBus adapter 1 */
272 	res1 = nforce2_probe_smb(dev, 4, NFORCE_PCI_SMB1, &smbuses[0], "SMB1");
273 	if (res1 < 0) {
274 		dev_err(&dev->dev, "Error probing SMB1.\n");
275 		smbuses[0].base = 0;	/* to have a check value */
276 	}
277 	/* SMBus adapter 2 */
278 	res2 = nforce2_probe_smb(dev, 5, NFORCE_PCI_SMB2, &smbuses[1], "SMB2");
279 	if (res2 < 0) {
280 		dev_err(&dev->dev, "Error probing SMB2.\n");
281 		smbuses[1].base = 0;	/* to have a check value */
282 	}
283 	if ((res1 < 0) && (res2 < 0)) {
284 		/* we did not find even one of the SMBuses, so we give up */
285 		kfree(smbuses);
286 		return -ENODEV;
287 	}
288 
289 	return 0;
290 }
291 
292 
293 static void __devexit nforce2_remove(struct pci_dev *dev)
294 {
295 	struct nforce2_smbus *smbuses = (void*) pci_get_drvdata(dev);
296 
297 	if (smbuses[0].base) {
298 		i2c_del_adapter(&smbuses[0].adapter);
299 		release_region(smbuses[0].base, smbuses[0].size);
300 	}
301 	if (smbuses[1].base) {
302 		i2c_del_adapter(&smbuses[1].adapter);
303 		release_region(smbuses[1].base, smbuses[1].size);
304 	}
305 	kfree(smbuses);
306 }
307 
308 static struct pci_driver nforce2_driver = {
309 	.name		= "nForce2_smbus",
310 	.id_table	= nforce2_ids,
311 	.probe		= nforce2_probe,
312 	.remove		= __devexit_p(nforce2_remove),
313 };
314 
315 static int __init nforce2_init(void)
316 {
317 	return pci_register_driver(&nforce2_driver);
318 }
319 
320 static void __exit nforce2_exit(void)
321 {
322 	pci_unregister_driver(&nforce2_driver);
323 }
324 
325 module_init(nforce2_init);
326 module_exit(nforce2_exit);
327 
328