xref: /openbmc/linux/drivers/i2c/busses/i2c-amd8111.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  * SMBus 2.0 driver for AMD-8111 IO-Hub.
3  *
4  * Copyright (c) 2002 Vojtech Pavlik
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation version 2.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <linux/kernel.h>
14 #include <linux/stddef.h>
15 #include <linux/ioport.h>
16 #include <linux/init.h>
17 #include <linux/i2c.h>
18 #include <linux/delay.h>
19 #include <asm/io.h>
20 
21 MODULE_LICENSE("GPL");
22 MODULE_AUTHOR ("Vojtech Pavlik <vojtech@suse.cz>");
23 MODULE_DESCRIPTION("AMD8111 SMBus 2.0 driver");
24 
25 struct amd_smbus {
26 	struct pci_dev *dev;
27 	struct i2c_adapter adapter;
28 	int base;
29 	int size;
30 };
31 
32 static struct pci_driver amd8111_driver;
33 
34 /*
35  * AMD PCI control registers definitions.
36  */
37 
38 #define AMD_PCI_MISC	0x48
39 
40 #define AMD_PCI_MISC_SCI	0x04	/* deliver SCI */
41 #define AMD_PCI_MISC_INT	0x02	/* deliver PCI IRQ */
42 #define AMD_PCI_MISC_SPEEDUP	0x01	/* 16x clock speedup */
43 
44 /*
45  * ACPI 2.0 chapter 13 PCI interface definitions.
46  */
47 
48 #define AMD_EC_DATA	0x00	/* data register */
49 #define AMD_EC_SC	0x04	/* status of controller */
50 #define AMD_EC_CMD	0x04	/* command register */
51 #define AMD_EC_ICR	0x08	/* interrupt control register */
52 
53 #define AMD_EC_SC_SMI	0x04	/* smi event pending */
54 #define AMD_EC_SC_SCI	0x02	/* sci event pending */
55 #define AMD_EC_SC_BURST	0x01	/* burst mode enabled */
56 #define AMD_EC_SC_CMD	0x08	/* byte in data reg is command */
57 #define AMD_EC_SC_IBF	0x02	/* data ready for embedded controller */
58 #define AMD_EC_SC_OBF	0x01	/* data ready for host */
59 
60 #define AMD_EC_CMD_RD	0x80	/* read EC */
61 #define AMD_EC_CMD_WR	0x81	/* write EC */
62 #define AMD_EC_CMD_BE	0x82	/* enable burst mode */
63 #define AMD_EC_CMD_BD	0x83	/* disable burst mode */
64 #define AMD_EC_CMD_QR	0x84	/* query EC */
65 
66 /*
67  * ACPI 2.0 chapter 13 access of registers of the EC
68  */
69 
70 static unsigned int amd_ec_wait_write(struct amd_smbus *smbus)
71 {
72 	int timeout = 500;
73 
74 	while (timeout-- && (inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_IBF))
75 		udelay(1);
76 
77 	if (!timeout) {
78 		dev_warn(&smbus->dev->dev,
79 			 "Timeout while waiting for IBF to clear\n");
80 		return -1;
81 	}
82 
83 	return 0;
84 }
85 
86 static unsigned int amd_ec_wait_read(struct amd_smbus *smbus)
87 {
88 	int timeout = 500;
89 
90 	while (timeout-- && (~inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_OBF))
91 		udelay(1);
92 
93 	if (!timeout) {
94 		dev_warn(&smbus->dev->dev,
95 			 "Timeout while waiting for OBF to set\n");
96 		return -1;
97 	}
98 
99 	return 0;
100 }
101 
102 static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
103 		unsigned char *data)
104 {
105 	if (amd_ec_wait_write(smbus))
106 		return -1;
107 	outb(AMD_EC_CMD_RD, smbus->base + AMD_EC_CMD);
108 
109 	if (amd_ec_wait_write(smbus))
110 		return -1;
111 	outb(address, smbus->base + AMD_EC_DATA);
112 
113 	if (amd_ec_wait_read(smbus))
114 		return -1;
115 	*data = inb(smbus->base + AMD_EC_DATA);
116 
117 	return 0;
118 }
119 
120 static unsigned int amd_ec_write(struct amd_smbus *smbus, unsigned char address,
121 		unsigned char data)
122 {
123 	if (amd_ec_wait_write(smbus))
124 		return -1;
125 	outb(AMD_EC_CMD_WR, smbus->base + AMD_EC_CMD);
126 
127 	if (amd_ec_wait_write(smbus))
128 		return -1;
129 	outb(address, smbus->base + AMD_EC_DATA);
130 
131 	if (amd_ec_wait_write(smbus))
132 		return -1;
133 	outb(data, smbus->base + AMD_EC_DATA);
134 
135 	return 0;
136 }
137 
138 /*
139  * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
140  */
141 
142 #define AMD_SMB_PRTCL	0x00	/* protocol, PEC */
143 #define AMD_SMB_STS	0x01	/* status */
144 #define AMD_SMB_ADDR	0x02	/* address */
145 #define AMD_SMB_CMD	0x03	/* command */
146 #define AMD_SMB_DATA	0x04	/* 32 data registers */
147 #define AMD_SMB_BCNT	0x24	/* number of data bytes */
148 #define AMD_SMB_ALRM_A	0x25	/* alarm address */
149 #define AMD_SMB_ALRM_D	0x26	/* 2 bytes alarm data */
150 
151 #define AMD_SMB_STS_DONE	0x80
152 #define AMD_SMB_STS_ALRM	0x40
153 #define AMD_SMB_STS_RES		0x20
154 #define AMD_SMB_STS_STATUS	0x1f
155 
156 #define AMD_SMB_STATUS_OK	0x00
157 #define AMD_SMB_STATUS_FAIL	0x07
158 #define AMD_SMB_STATUS_DNAK	0x10
159 #define AMD_SMB_STATUS_DERR	0x11
160 #define AMD_SMB_STATUS_CMD_DENY	0x12
161 #define AMD_SMB_STATUS_UNKNOWN	0x13
162 #define AMD_SMB_STATUS_ACC_DENY	0x17
163 #define AMD_SMB_STATUS_TIMEOUT	0x18
164 #define AMD_SMB_STATUS_NOTSUP	0x19
165 #define AMD_SMB_STATUS_BUSY	0x1A
166 #define AMD_SMB_STATUS_PEC	0x1F
167 
168 #define AMD_SMB_PRTCL_WRITE		0x00
169 #define AMD_SMB_PRTCL_READ		0x01
170 #define AMD_SMB_PRTCL_QUICK		0x02
171 #define AMD_SMB_PRTCL_BYTE		0x04
172 #define AMD_SMB_PRTCL_BYTE_DATA		0x06
173 #define AMD_SMB_PRTCL_WORD_DATA		0x08
174 #define AMD_SMB_PRTCL_BLOCK_DATA	0x0a
175 #define AMD_SMB_PRTCL_PROC_CALL		0x0c
176 #define AMD_SMB_PRTCL_BLOCK_PROC_CALL	0x0d
177 #define AMD_SMB_PRTCL_I2C_BLOCK_DATA	0x4a
178 #define AMD_SMB_PRTCL_PEC		0x80
179 
180 
181 static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
182 		unsigned short flags, char read_write, u8 command, int size,
183 		union i2c_smbus_data * data)
184 {
185 	struct amd_smbus *smbus = adap->algo_data;
186 	unsigned char protocol, len, pec, temp[2];
187 	int i;
188 
189 	protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ
190 						  : AMD_SMB_PRTCL_WRITE;
191 	pec = (flags & I2C_CLIENT_PEC) ? AMD_SMB_PRTCL_PEC : 0;
192 
193 	switch (size) {
194 		case I2C_SMBUS_QUICK:
195 			protocol |= AMD_SMB_PRTCL_QUICK;
196 			read_write = I2C_SMBUS_WRITE;
197 			break;
198 
199 		case I2C_SMBUS_BYTE:
200 			if (read_write == I2C_SMBUS_WRITE)
201 				amd_ec_write(smbus, AMD_SMB_CMD, command);
202 			protocol |= AMD_SMB_PRTCL_BYTE;
203 			break;
204 
205 		case I2C_SMBUS_BYTE_DATA:
206 			amd_ec_write(smbus, AMD_SMB_CMD, command);
207 			if (read_write == I2C_SMBUS_WRITE)
208 				amd_ec_write(smbus, AMD_SMB_DATA, data->byte);
209 			protocol |= AMD_SMB_PRTCL_BYTE_DATA;
210 			break;
211 
212 		case I2C_SMBUS_WORD_DATA:
213 			amd_ec_write(smbus, AMD_SMB_CMD, command);
214 			if (read_write == I2C_SMBUS_WRITE) {
215 				amd_ec_write(smbus, AMD_SMB_DATA,
216 					     data->word & 0xff);
217 				amd_ec_write(smbus, AMD_SMB_DATA + 1,
218 					     data->word >> 8);
219 			}
220 			protocol |= AMD_SMB_PRTCL_WORD_DATA | pec;
221 			break;
222 
223 		case I2C_SMBUS_BLOCK_DATA:
224 			amd_ec_write(smbus, AMD_SMB_CMD, command);
225 			if (read_write == I2C_SMBUS_WRITE) {
226 				len = min_t(u8, data->block[0],
227 					    I2C_SMBUS_BLOCK_MAX);
228 				amd_ec_write(smbus, AMD_SMB_BCNT, len);
229 				for (i = 0; i < len; i++)
230 					amd_ec_write(smbus, AMD_SMB_DATA + i,
231 						     data->block[i + 1]);
232 			}
233 			protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec;
234 			break;
235 
236 		case I2C_SMBUS_I2C_BLOCK_DATA:
237 			len = min_t(u8, data->block[0],
238 				    I2C_SMBUS_BLOCK_MAX);
239 			amd_ec_write(smbus, AMD_SMB_CMD, command);
240 			amd_ec_write(smbus, AMD_SMB_BCNT, len);
241 			if (read_write == I2C_SMBUS_WRITE)
242 				for (i = 0; i < len; i++)
243 					amd_ec_write(smbus, AMD_SMB_DATA + i,
244 						     data->block[i + 1]);
245 			protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA;
246 			break;
247 
248 		case I2C_SMBUS_PROC_CALL:
249 			amd_ec_write(smbus, AMD_SMB_CMD, command);
250 			amd_ec_write(smbus, AMD_SMB_DATA, data->word & 0xff);
251 			amd_ec_write(smbus, AMD_SMB_DATA + 1, data->word >> 8);
252 			protocol = AMD_SMB_PRTCL_PROC_CALL | pec;
253 			read_write = I2C_SMBUS_READ;
254 			break;
255 
256 		case I2C_SMBUS_BLOCK_PROC_CALL:
257 			len = min_t(u8, data->block[0],
258 				    I2C_SMBUS_BLOCK_MAX - 1);
259 			amd_ec_write(smbus, AMD_SMB_CMD, command);
260 			amd_ec_write(smbus, AMD_SMB_BCNT, len);
261 			for (i = 0; i < len; i++)
262 				amd_ec_write(smbus, AMD_SMB_DATA + i,
263 					     data->block[i + 1]);
264 			protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec;
265 			read_write = I2C_SMBUS_READ;
266 			break;
267 
268 		default:
269 			dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
270 			return -1;
271 	}
272 
273 	amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
274 	amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
275 
276 	amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
277 
278 	if (~temp[0] & AMD_SMB_STS_DONE) {
279 		udelay(500);
280 		amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
281 	}
282 
283 	if (~temp[0] & AMD_SMB_STS_DONE) {
284 		msleep(1);
285 		amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
286 	}
287 
288 	if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS))
289 		return -1;
290 
291 	if (read_write == I2C_SMBUS_WRITE)
292 		return 0;
293 
294 	switch (size) {
295 		case I2C_SMBUS_BYTE:
296 		case I2C_SMBUS_BYTE_DATA:
297 			amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
298 			break;
299 
300 		case I2C_SMBUS_WORD_DATA:
301 		case I2C_SMBUS_PROC_CALL:
302 			amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
303 			amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
304 			data->word = (temp[1] << 8) | temp[0];
305 			break;
306 
307 		case I2C_SMBUS_BLOCK_DATA:
308 		case I2C_SMBUS_BLOCK_PROC_CALL:
309 			amd_ec_read(smbus, AMD_SMB_BCNT, &len);
310 			len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);
311 		case I2C_SMBUS_I2C_BLOCK_DATA:
312 			for (i = 0; i < len; i++)
313 				amd_ec_read(smbus, AMD_SMB_DATA + i,
314 					    data->block + i + 1);
315 			data->block[0] = len;
316 			break;
317 	}
318 
319 	return 0;
320 }
321 
322 
323 static u32 amd8111_func(struct i2c_adapter *adapter)
324 {
325 	return	I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
326 		I2C_FUNC_SMBUS_BYTE_DATA |
327 		I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA |
328 		I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
329 		I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_PEC;
330 }
331 
332 static const struct i2c_algorithm smbus_algorithm = {
333 	.smbus_xfer = amd8111_access,
334 	.functionality = amd8111_func,
335 };
336 
337 
338 static struct pci_device_id amd8111_ids[] = {
339 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS2) },
340 	{ 0, }
341 };
342 
343 MODULE_DEVICE_TABLE (pci, amd8111_ids);
344 
345 static int __devinit amd8111_probe(struct pci_dev *dev,
346 		const struct pci_device_id *id)
347 {
348 	struct amd_smbus *smbus;
349 	int error;
350 
351 	if (!(pci_resource_flags(dev, 0) & IORESOURCE_IO))
352 		return -ENODEV;
353 
354 	smbus = kzalloc(sizeof(struct amd_smbus), GFP_KERNEL);
355 	if (!smbus)
356 		return -ENOMEM;
357 
358 	smbus->dev = dev;
359 	smbus->base = pci_resource_start(dev, 0);
360 	smbus->size = pci_resource_len(dev, 0);
361 
362 	if (!request_region(smbus->base, smbus->size, amd8111_driver.name)) {
363 		error = -EBUSY;
364 		goto out_kfree;
365 	}
366 
367 	smbus->adapter.owner = THIS_MODULE;
368 	snprintf(smbus->adapter.name, sizeof(smbus->adapter.name),
369 		"SMBus2 AMD8111 adapter at %04x", smbus->base);
370 	smbus->adapter.id = I2C_HW_SMBUS_AMD8111;
371 	smbus->adapter.class = I2C_CLASS_HWMON;
372 	smbus->adapter.algo = &smbus_algorithm;
373 	smbus->adapter.algo_data = smbus;
374 
375 	/* set up the sysfs linkage to our parent device */
376 	smbus->adapter.dev.parent = &dev->dev;
377 
378 	pci_write_config_dword(smbus->dev, AMD_PCI_MISC, 0);
379 	error = i2c_add_adapter(&smbus->adapter);
380 	if (error)
381 		goto out_release_region;
382 
383 	pci_set_drvdata(dev, smbus);
384 	return 0;
385 
386  out_release_region:
387 	release_region(smbus->base, smbus->size);
388  out_kfree:
389 	kfree(smbus);
390 	return error;
391 }
392 
393 static void __devexit amd8111_remove(struct pci_dev *dev)
394 {
395 	struct amd_smbus *smbus = pci_get_drvdata(dev);
396 
397 	i2c_del_adapter(&smbus->adapter);
398 	release_region(smbus->base, smbus->size);
399 	kfree(smbus);
400 }
401 
402 static struct pci_driver amd8111_driver = {
403 	.name		= "amd8111_smbus2",
404 	.id_table	= amd8111_ids,
405 	.probe		= amd8111_probe,
406 	.remove		= __devexit_p(amd8111_remove),
407 };
408 
409 static int __init i2c_amd8111_init(void)
410 {
411 	return pci_register_driver(&amd8111_driver);
412 }
413 
414 static void __exit i2c_amd8111_exit(void)
415 {
416 	pci_unregister_driver(&amd8111_driver);
417 }
418 
419 module_init(i2c_amd8111_init);
420 module_exit(i2c_amd8111_exit);
421