xref: /openbmc/linux/drivers/i2c/busses/i2c-amd8111.c (revision 87c2ce3b)
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/sched.h>
16 #include <linux/ioport.h>
17 #include <linux/init.h>
18 #include <linux/i2c.h>
19 #include <linux/delay.h>
20 #include <asm/io.h>
21 
22 MODULE_LICENSE("GPL");
23 MODULE_AUTHOR ("Vojtech Pavlik <vojtech@suse.cz>");
24 MODULE_DESCRIPTION("AMD8111 SMBus 2.0 driver");
25 
26 struct amd_smbus {
27 	struct pci_dev *dev;
28 	struct i2c_adapter adapter;
29 	int base;
30 	int size;
31 };
32 
33 static struct pci_driver amd8111_driver;
34 
35 /*
36  * AMD PCI control registers definitions.
37  */
38 
39 #define AMD_PCI_MISC	0x48
40 
41 #define AMD_PCI_MISC_SCI	0x04	/* deliver SCI */
42 #define AMD_PCI_MISC_INT	0x02	/* deliver PCI IRQ */
43 #define AMD_PCI_MISC_SPEEDUP	0x01	/* 16x clock speedup */
44 
45 /*
46  * ACPI 2.0 chapter 13 PCI interface definitions.
47  */
48 
49 #define AMD_EC_DATA	0x00	/* data register */
50 #define AMD_EC_SC	0x04	/* status of controller */
51 #define AMD_EC_CMD	0x04	/* command register */
52 #define AMD_EC_ICR	0x08	/* interrupt control register */
53 
54 #define AMD_EC_SC_SMI	0x04	/* smi event pending */
55 #define AMD_EC_SC_SCI	0x02	/* sci event pending */
56 #define AMD_EC_SC_BURST	0x01	/* burst mode enabled */
57 #define AMD_EC_SC_CMD	0x08	/* byte in data reg is command */
58 #define AMD_EC_SC_IBF	0x02	/* data ready for embedded controller */
59 #define AMD_EC_SC_OBF	0x01	/* data ready for host */
60 
61 #define AMD_EC_CMD_RD	0x80	/* read EC */
62 #define AMD_EC_CMD_WR	0x81	/* write EC */
63 #define AMD_EC_CMD_BE	0x82	/* enable burst mode */
64 #define AMD_EC_CMD_BD	0x83	/* disable burst mode */
65 #define AMD_EC_CMD_QR	0x84	/* query EC */
66 
67 /*
68  * ACPI 2.0 chapter 13 access of registers of the EC
69  */
70 
71 static unsigned int amd_ec_wait_write(struct amd_smbus *smbus)
72 {
73 	int timeout = 500;
74 
75 	while (timeout-- && (inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_IBF))
76 		udelay(1);
77 
78 	if (!timeout) {
79 		dev_warn(&smbus->dev->dev, "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, "Timeout while waiting for OBF to set\n");
95 		return -1;
96 	}
97 
98 	return 0;
99 }
100 
101 static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address, unsigned char *data)
102 {
103 	if (amd_ec_wait_write(smbus))
104 		return -1;
105 	outb(AMD_EC_CMD_RD, smbus->base + AMD_EC_CMD);
106 
107 	if (amd_ec_wait_write(smbus))
108 		return -1;
109 	outb(address, smbus->base + AMD_EC_DATA);
110 
111 	if (amd_ec_wait_read(smbus))
112 		return -1;
113 	*data = inb(smbus->base + AMD_EC_DATA);
114 
115 	return 0;
116 }
117 
118 static unsigned int amd_ec_write(struct amd_smbus *smbus, unsigned char address, unsigned char data)
119 {
120 	if (amd_ec_wait_write(smbus))
121 		return -1;
122 	outb(AMD_EC_CMD_WR, smbus->base + AMD_EC_CMD);
123 
124 	if (amd_ec_wait_write(smbus))
125 		return -1;
126 	outb(address, smbus->base + AMD_EC_DATA);
127 
128 	if (amd_ec_wait_write(smbus))
129 		return -1;
130 	outb(data, smbus->base + AMD_EC_DATA);
131 
132 	return 0;
133 }
134 
135 /*
136  * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
137  */
138 
139 #define AMD_SMB_PRTCL	0x00	/* protocol, PEC */
140 #define AMD_SMB_STS	0x01	/* status */
141 #define AMD_SMB_ADDR	0x02	/* address */
142 #define AMD_SMB_CMD	0x03	/* command */
143 #define AMD_SMB_DATA	0x04	/* 32 data registers */
144 #define AMD_SMB_BCNT	0x24	/* number of data bytes */
145 #define AMD_SMB_ALRM_A	0x25	/* alarm address */
146 #define AMD_SMB_ALRM_D	0x26	/* 2 bytes alarm data */
147 
148 #define AMD_SMB_STS_DONE	0x80
149 #define AMD_SMB_STS_ALRM	0x40
150 #define AMD_SMB_STS_RES		0x20
151 #define AMD_SMB_STS_STATUS	0x1f
152 
153 #define AMD_SMB_STATUS_OK	0x00
154 #define AMD_SMB_STATUS_FAIL	0x07
155 #define AMD_SMB_STATUS_DNAK	0x10
156 #define AMD_SMB_STATUS_DERR	0x11
157 #define AMD_SMB_STATUS_CMD_DENY	0x12
158 #define AMD_SMB_STATUS_UNKNOWN	0x13
159 #define AMD_SMB_STATUS_ACC_DENY	0x17
160 #define AMD_SMB_STATUS_TIMEOUT	0x18
161 #define AMD_SMB_STATUS_NOTSUP	0x19
162 #define AMD_SMB_STATUS_BUSY	0x1A
163 #define AMD_SMB_STATUS_PEC	0x1F
164 
165 #define AMD_SMB_PRTCL_WRITE		0x00
166 #define AMD_SMB_PRTCL_READ		0x01
167 #define AMD_SMB_PRTCL_QUICK		0x02
168 #define AMD_SMB_PRTCL_BYTE		0x04
169 #define AMD_SMB_PRTCL_BYTE_DATA		0x06
170 #define AMD_SMB_PRTCL_WORD_DATA		0x08
171 #define AMD_SMB_PRTCL_BLOCK_DATA	0x0a
172 #define AMD_SMB_PRTCL_PROC_CALL		0x0c
173 #define AMD_SMB_PRTCL_BLOCK_PROC_CALL	0x0d
174 #define AMD_SMB_PRTCL_I2C_BLOCK_DATA	0x4a
175 #define AMD_SMB_PRTCL_PEC		0x80
176 
177 
178 static s32 amd8111_access(struct i2c_adapter * adap, u16 addr, unsigned short flags,
179 		char read_write, u8 command, int size, union i2c_smbus_data * data)
180 {
181 	struct amd_smbus *smbus = adap->algo_data;
182 	unsigned char protocol, len, pec, temp[2];
183 	int i;
184 
185 	protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ : AMD_SMB_PRTCL_WRITE;
186 	pec = (flags & I2C_CLIENT_PEC) ? AMD_SMB_PRTCL_PEC : 0;
187 
188 	switch (size) {
189 
190 		case I2C_SMBUS_QUICK:
191 			protocol |= AMD_SMB_PRTCL_QUICK;
192 			read_write = I2C_SMBUS_WRITE;
193 			break;
194 
195 		case I2C_SMBUS_BYTE:
196 			if (read_write == I2C_SMBUS_WRITE)
197 				amd_ec_write(smbus, AMD_SMB_CMD, command);
198 			protocol |= AMD_SMB_PRTCL_BYTE;
199 			break;
200 
201 		case I2C_SMBUS_BYTE_DATA:
202 			amd_ec_write(smbus, AMD_SMB_CMD, command);
203 			if (read_write == I2C_SMBUS_WRITE)
204 				amd_ec_write(smbus, AMD_SMB_DATA, data->byte);
205 			protocol |= AMD_SMB_PRTCL_BYTE_DATA;
206 			break;
207 
208 		case I2C_SMBUS_WORD_DATA:
209 			amd_ec_write(smbus, AMD_SMB_CMD, command);
210 			if (read_write == I2C_SMBUS_WRITE) {
211 				amd_ec_write(smbus, AMD_SMB_DATA, data->word);
212 				amd_ec_write(smbus, AMD_SMB_DATA + 1, data->word >> 8);
213 			}
214 			protocol |= AMD_SMB_PRTCL_WORD_DATA | pec;
215 			break;
216 
217 		case I2C_SMBUS_BLOCK_DATA:
218 			amd_ec_write(smbus, AMD_SMB_CMD, command);
219 			if (read_write == I2C_SMBUS_WRITE) {
220 				len = min_t(u8, data->block[0], 32);
221 				amd_ec_write(smbus, AMD_SMB_BCNT, len);
222 				for (i = 0; i < len; i++)
223 					amd_ec_write(smbus, AMD_SMB_DATA + i, data->block[i + 1]);
224 			}
225 			protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec;
226 			break;
227 
228 		case I2C_SMBUS_I2C_BLOCK_DATA:
229 			len = min_t(u8, data->block[0], 32);
230 			amd_ec_write(smbus, AMD_SMB_CMD, command);
231 			amd_ec_write(smbus, AMD_SMB_BCNT, len);
232 			if (read_write == I2C_SMBUS_WRITE)
233 				for (i = 0; i < len; i++)
234 					amd_ec_write(smbus, AMD_SMB_DATA + i, data->block[i + 1]);
235 			protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA;
236 			break;
237 
238 		case I2C_SMBUS_PROC_CALL:
239 			amd_ec_write(smbus, AMD_SMB_CMD, command);
240 			amd_ec_write(smbus, AMD_SMB_DATA, data->word);
241 			amd_ec_write(smbus, AMD_SMB_DATA + 1, data->word >> 8);
242 			protocol = AMD_SMB_PRTCL_PROC_CALL | pec;
243 			read_write = I2C_SMBUS_READ;
244 			break;
245 
246 		case I2C_SMBUS_BLOCK_PROC_CALL:
247 			len = min_t(u8, data->block[0], 31);
248 			amd_ec_write(smbus, AMD_SMB_CMD, command);
249 			amd_ec_write(smbus, AMD_SMB_BCNT, len);
250 			for (i = 0; i < len; i++)
251 				amd_ec_write(smbus, AMD_SMB_DATA + i, data->block[i + 1]);
252 			protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec;
253 			read_write = I2C_SMBUS_READ;
254 			break;
255 
256 		default:
257 			dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
258 			return -1;
259 	}
260 
261 	amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
262 	amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
263 
264 	amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
265 
266 	if (~temp[0] & AMD_SMB_STS_DONE) {
267 		udelay(500);
268 		amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
269 	}
270 
271 	if (~temp[0] & AMD_SMB_STS_DONE) {
272 		msleep(1);
273 		amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
274 	}
275 
276 	if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS))
277 		return -1;
278 
279 	if (read_write == I2C_SMBUS_WRITE)
280 		return 0;
281 
282 	switch (size) {
283 
284 		case I2C_SMBUS_BYTE:
285 		case I2C_SMBUS_BYTE_DATA:
286 			amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
287 			break;
288 
289 		case I2C_SMBUS_WORD_DATA:
290 		case I2C_SMBUS_PROC_CALL:
291 			amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
292 			amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
293 			data->word = (temp[1] << 8) | temp[0];
294 			break;
295 
296 		case I2C_SMBUS_BLOCK_DATA:
297 		case I2C_SMBUS_BLOCK_PROC_CALL:
298 			amd_ec_read(smbus, AMD_SMB_BCNT, &len);
299 			len = min_t(u8, len, 32);
300 		case I2C_SMBUS_I2C_BLOCK_DATA:
301 			for (i = 0; i < len; i++)
302 				amd_ec_read(smbus, AMD_SMB_DATA + i, data->block + i + 1);
303 			data->block[0] = len;
304 			break;
305 	}
306 
307 	return 0;
308 }
309 
310 
311 static u32 amd8111_func(struct i2c_adapter *adapter)
312 {
313 	return	I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA |
314 		I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA |
315 		I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
316 		I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_HWPEC_CALC;
317 }
318 
319 static struct i2c_algorithm smbus_algorithm = {
320 	.smbus_xfer = amd8111_access,
321 	.functionality = amd8111_func,
322 };
323 
324 
325 static struct pci_device_id amd8111_ids[] = {
326 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS2) },
327 	{ 0, }
328 };
329 
330 MODULE_DEVICE_TABLE (pci, amd8111_ids);
331 
332 static int __devinit amd8111_probe(struct pci_dev *dev, const struct pci_device_id *id)
333 {
334 	struct amd_smbus *smbus;
335 	int error = -ENODEV;
336 
337 	if (~pci_resource_flags(dev, 0) & IORESOURCE_IO)
338 		return -ENODEV;
339 
340 	smbus = kzalloc(sizeof(struct amd_smbus), GFP_KERNEL);
341 	if (!smbus)
342 		return -ENOMEM;
343 
344 	smbus->dev = dev;
345 	smbus->base = pci_resource_start(dev, 0);
346 	smbus->size = pci_resource_len(dev, 0);
347 
348 	if (!request_region(smbus->base, smbus->size, amd8111_driver.name))
349 		goto out_kfree;
350 
351 	smbus->adapter.owner = THIS_MODULE;
352 	snprintf(smbus->adapter.name, I2C_NAME_SIZE,
353 		"SMBus2 AMD8111 adapter at %04x", smbus->base);
354 	smbus->adapter.class = I2C_CLASS_HWMON;
355 	smbus->adapter.algo = &smbus_algorithm;
356 	smbus->adapter.algo_data = smbus;
357 
358 	/* set up the driverfs linkage to our parent device */
359 	smbus->adapter.dev.parent = &dev->dev;
360 
361 	error = i2c_add_adapter(&smbus->adapter);
362 	if (error)
363 		goto out_release_region;
364 
365 	pci_write_config_dword(smbus->dev, AMD_PCI_MISC, 0);
366 	pci_set_drvdata(dev, smbus);
367 	return 0;
368 
369  out_release_region:
370 	release_region(smbus->base, smbus->size);
371  out_kfree:
372 	kfree(smbus);
373 	return -1;
374 }
375 
376 
377 static void __devexit amd8111_remove(struct pci_dev *dev)
378 {
379 	struct amd_smbus *smbus = pci_get_drvdata(dev);
380 
381 	i2c_del_adapter(&smbus->adapter);
382 	release_region(smbus->base, smbus->size);
383 	kfree(smbus);
384 }
385 
386 static struct pci_driver amd8111_driver = {
387 	.name		= "amd8111_smbus2",
388 	.id_table	= amd8111_ids,
389 	.probe		= amd8111_probe,
390 	.remove		= __devexit_p(amd8111_remove),
391 };
392 
393 static int __init i2c_amd8111_init(void)
394 {
395 	return pci_register_driver(&amd8111_driver);
396 }
397 
398 
399 static void __exit i2c_amd8111_exit(void)
400 {
401 	pci_unregister_driver(&amd8111_driver);
402 }
403 
404 module_init(i2c_amd8111_init);
405 module_exit(i2c_amd8111_exit);
406