i2c-ali1563.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *	i2c-ali1563.c - i2c driver for the ALi 1563 Southbridge
  4 *
  5 *	Copyright (C) 2004 Patrick Mochel
  6 *		      2005 Rudolf Marek <r.marek@assembler.cz>
  7 *
  8 *	The 1563 southbridge is deceptively similar to the 1533, with a
  9 *	few notable exceptions. One of those happens to be the fact they
 10 *	upgraded the i2c core to be 2.0 compliant, and happens to be almost
 11 *	identical to the i2c controller found in the Intel 801 south
 12 *	bridges.
 13 *
 14 *	This driver is based on a mix of the 15x3, 1535, and i801 drivers,
 15 *	with a little help from the ALi 1563 spec.
 16 */
 17
 18#include <linux/module.h>
 19#include <linux/delay.h>
 20#include <linux/i2c.h>
 21#include <linux/pci.h>
 22#include <linux/acpi.h>
 23
 24#define ALI1563_MAX_TIMEOUT	500
 25#define	ALI1563_SMBBA		0x80
 26#define ALI1563_SMB_IOEN	1
 27#define ALI1563_SMB_HOSTEN	2
 28#define ALI1563_SMB_IOSIZE	16
 29
 30#define SMB_HST_STS	(ali1563_smba + 0)
 31#define SMB_HST_CNTL1	(ali1563_smba + 1)
 32#define SMB_HST_CNTL2	(ali1563_smba + 2)
 33#define SMB_HST_CMD	(ali1563_smba + 3)
 34#define SMB_HST_ADD	(ali1563_smba + 4)
 35#define SMB_HST_DAT0	(ali1563_smba + 5)
 36#define SMB_HST_DAT1	(ali1563_smba + 6)
 37#define SMB_BLK_DAT	(ali1563_smba + 7)
 38
 39#define HST_STS_BUSY	0x01
 40#define HST_STS_INTR	0x02
 41#define HST_STS_DEVERR	0x04
 42#define HST_STS_BUSERR	0x08
 43#define HST_STS_FAIL	0x10
 44#define HST_STS_DONE	0x80
 45#define HST_STS_BAD	0x1c
 46
 47
 48#define HST_CNTL1_TIMEOUT	0x80
 49#define HST_CNTL1_LAST		0x40
 50
 51#define HST_CNTL2_KILL		0x04
 52#define HST_CNTL2_START		0x40
 53#define HST_CNTL2_QUICK		0x00
 54#define HST_CNTL2_BYTE		0x01
 55#define HST_CNTL2_BYTE_DATA	0x02
 56#define HST_CNTL2_WORD_DATA	0x03
 57#define HST_CNTL2_BLOCK		0x05
 58
 59
 60#define HST_CNTL2_SIZEMASK	0x38
 61
 62static struct pci_driver ali1563_pci_driver;
 63static unsigned short ali1563_smba;
 64
 65static int ali1563_transaction(struct i2c_adapter *a, int size)
 66{
 67	u32 data;
 68	int timeout;
 69	int status = -EIO;
 70
 71	dev_dbg(&a->dev, "Transaction (pre): STS=%02x, CNTL1=%02x, "
 72		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
 73		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
 74		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
 75		inb_p(SMB_HST_DAT1));
 76
 77	data = inb_p(SMB_HST_STS);
 78	if (data & HST_STS_BAD) {
 79		dev_err(&a->dev, "ali1563: Trying to reset busy device\n");
 80		outb_p(data | HST_STS_BAD, SMB_HST_STS);
 81		data = inb_p(SMB_HST_STS);
 82		if (data & HST_STS_BAD)
 83			return -EBUSY;
 84	}
 85	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2);
 86
 87	timeout = ALI1563_MAX_TIMEOUT;
 88	do {
 89		msleep(1);
 90	} while (((data = inb_p(SMB_HST_STS)) & HST_STS_BUSY) && --timeout);
 91
 92	dev_dbg(&a->dev, "Transaction (post): STS=%02x, CNTL1=%02x, "
 93		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
 94		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
 95		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
 96		inb_p(SMB_HST_DAT1));
 97
 98	if (timeout && !(data & HST_STS_BAD))
 99		return 0;
100
101	if (!timeout) {
102		/* Issue 'kill' to host controller */
103		outb_p(HST_CNTL2_KILL, SMB_HST_CNTL2);
104		data = inb_p(SMB_HST_STS);
105		status = -ETIMEDOUT;
106	}
107
108	/* device error - no response, ignore the autodetection case */
109	if (data & HST_STS_DEVERR) {
110		if (size != HST_CNTL2_QUICK)
111			dev_err(&a->dev, "Device error!\n");
112		status = -ENXIO;
113	}
114	/* bus collision */
115	if (data & HST_STS_BUSERR) {
116		dev_err(&a->dev, "Bus collision!\n");
117		/* Issue timeout, hoping it helps */
118		outb_p(HST_CNTL1_TIMEOUT, SMB_HST_CNTL1);
119	}
120
121	if (data & HST_STS_FAIL) {
122		dev_err(&a->dev, "Cleaning fail after KILL!\n");
123		outb_p(0x0, SMB_HST_CNTL2);
124	}
125
126	return status;
127}
128
129static int ali1563_block_start(struct i2c_adapter *a)
130{
131	u32 data;
132	int timeout;
133	int status = -EIO;
134
135	dev_dbg(&a->dev, "Block (pre): STS=%02x, CNTL1=%02x, "
136		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
137		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
138		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
139		inb_p(SMB_HST_DAT1));
140
141	data = inb_p(SMB_HST_STS);
142	if (data & HST_STS_BAD) {
143		dev_warn(&a->dev, "ali1563: Trying to reset busy device\n");
144		outb_p(data | HST_STS_BAD, SMB_HST_STS);
145		data = inb_p(SMB_HST_STS);
146		if (data & HST_STS_BAD)
147			return -EBUSY;
148	}
149
150	/* Clear byte-ready bit */
151	outb_p(data | HST_STS_DONE, SMB_HST_STS);
152
153	/* Start transaction and wait for byte-ready bit to be set */
154	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_START, SMB_HST_CNTL2);
155
156	timeout = ALI1563_MAX_TIMEOUT;
157	do {
158		msleep(1);
159	} while (!((data = inb_p(SMB_HST_STS)) & HST_STS_DONE) && --timeout);
160
161	dev_dbg(&a->dev, "Block (post): STS=%02x, CNTL1=%02x, "
162		"CNTL2=%02x, CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
163		inb_p(SMB_HST_STS), inb_p(SMB_HST_CNTL1), inb_p(SMB_HST_CNTL2),
164		inb_p(SMB_HST_CMD), inb_p(SMB_HST_ADD), inb_p(SMB_HST_DAT0),
165		inb_p(SMB_HST_DAT1));
166
167	if (timeout && !(data & HST_STS_BAD))
168		return 0;
169
170	if (timeout == 0)
171		status = -ETIMEDOUT;
172
173	if (data & HST_STS_DEVERR)
174		status = -ENXIO;
175
176	dev_err(&a->dev, "SMBus Error: %s%s%s%s%s\n",
177		timeout ? "" : "Timeout ",
178		data & HST_STS_FAIL ? "Transaction Failed " : "",
179		data & HST_STS_BUSERR ? "No response or Bus Collision " : "",
180		data & HST_STS_DEVERR ? "Device Error " : "",
181		!(data & HST_STS_DONE) ? "Transaction Never Finished " : "");
182	return status;
183}
184
185static int ali1563_block(struct i2c_adapter *a,
186			 union i2c_smbus_data *data, u8 rw)
187{
188	int i, len;
189	int error = 0;
190
191	/* Do we need this? */
192	outb_p(HST_CNTL1_LAST, SMB_HST_CNTL1);
193
194	if (rw == I2C_SMBUS_WRITE) {
195		len = data->block[0];
196		if (len < 1)
197			len = 1;
198		else if (len > 32)
199			len = 32;
200		outb_p(len, SMB_HST_DAT0);
201		outb_p(data->block[1], SMB_BLK_DAT);
202	} else
203		len = 32;
204
205	outb_p(inb_p(SMB_HST_CNTL2) | HST_CNTL2_BLOCK, SMB_HST_CNTL2);
206
207	for (i = 0; i < len; i++) {
208		if (rw == I2C_SMBUS_WRITE) {
209			outb_p(data->block[i + 1], SMB_BLK_DAT);
210			error = ali1563_block_start(a);
211			if (error)
212				break;
213		} else {
214			error = ali1563_block_start(a);
215			if (error)
216				break;
217			if (i == 0) {
218				len = inb_p(SMB_HST_DAT0);
219				if (len < 1)
220					len = 1;
221				else if (len > 32)
222					len = 32;
223			}
224			data->block[i+1] = inb_p(SMB_BLK_DAT);
225		}
226	}
227	/* Do we need this? */
228	outb_p(HST_CNTL1_LAST, SMB_HST_CNTL1);
229	return error;
230}
231
232static s32 ali1563_access(struct i2c_adapter *a, u16 addr,
233			  unsigned short flags, char rw, u8 cmd,
234			  int size, union i2c_smbus_data *data)
235{
236	int error = 0;
237	int timeout;
238	u32 reg;
239
240	for (timeout = ALI1563_MAX_TIMEOUT; timeout; timeout--) {
241		reg = inb_p(SMB_HST_STS);
242		if (!(reg & HST_STS_BUSY))
243			break;
244	}
245	if (!timeout)
246		dev_warn(&a->dev, "SMBus not idle. HST_STS = %02x\n", reg);
247	outb_p(0xff, SMB_HST_STS);
248
249	/* Map the size to what the chip understands */
250	switch (size) {
251	case I2C_SMBUS_QUICK:
252		size = HST_CNTL2_QUICK;
253		break;
254	case I2C_SMBUS_BYTE:
255		size = HST_CNTL2_BYTE;
256		break;
257	case I2C_SMBUS_BYTE_DATA:
258		size = HST_CNTL2_BYTE_DATA;
259		break;
260	case I2C_SMBUS_WORD_DATA:
261		size = HST_CNTL2_WORD_DATA;
262		break;
263	case I2C_SMBUS_BLOCK_DATA:
264		size = HST_CNTL2_BLOCK;
265		break;
266	default:
267		dev_warn(&a->dev, "Unsupported transaction %d\n", size);
268		error = -EOPNOTSUPP;
269		goto Done;
270	}
271
272	outb_p(((addr & 0x7f) << 1) | (rw & 0x01), SMB_HST_ADD);
273	outb_p((inb_p(SMB_HST_CNTL2) & ~HST_CNTL2_SIZEMASK) |
274	       (size << 3), SMB_HST_CNTL2);
275
276	/* Write the command register */
277
278	switch (size) {
279	case HST_CNTL2_BYTE:
280		if (rw == I2C_SMBUS_WRITE)
281			/* Beware it uses DAT0 register and not CMD! */
282			outb_p(cmd, SMB_HST_DAT0);
283		break;
284	case HST_CNTL2_BYTE_DATA:
285		outb_p(cmd, SMB_HST_CMD);
286		if (rw == I2C_SMBUS_WRITE)
287			outb_p(data->byte, SMB_HST_DAT0);
288		break;
289	case HST_CNTL2_WORD_DATA:
290		outb_p(cmd, SMB_HST_CMD);
291		if (rw == I2C_SMBUS_WRITE) {
292			outb_p(data->word & 0xff, SMB_HST_DAT0);
293			outb_p((data->word & 0xff00) >> 8, SMB_HST_DAT1);
294		}
295		break;
296	case HST_CNTL2_BLOCK:
297		outb_p(cmd, SMB_HST_CMD);
298		error = ali1563_block(a, data, rw);
299		goto Done;
300	}
301
302	error = ali1563_transaction(a, size);
303	if (error)
304		goto Done;
305
306	if ((rw == I2C_SMBUS_WRITE) || (size == HST_CNTL2_QUICK))
307		goto Done;
308
309	switch (size) {
310	case HST_CNTL2_BYTE:	/* Result put in SMBHSTDAT0 */
311		data->byte = inb_p(SMB_HST_DAT0);
312		break;
313	case HST_CNTL2_BYTE_DATA:
314		data->byte = inb_p(SMB_HST_DAT0);
315		break;
316	case HST_CNTL2_WORD_DATA:
317		data->word = inb_p(SMB_HST_DAT0) + (inb_p(SMB_HST_DAT1) << 8);
318		break;
319	}
320Done:
321	return error;
322}
323
324static u32 ali1563_func(struct i2c_adapter *a)
325{
326	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
327	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
328	    I2C_FUNC_SMBUS_BLOCK_DATA;
329}
330
331
332static int ali1563_setup(struct pci_dev *dev)
333{
334	u16 ctrl;
335
336	pci_read_config_word(dev, ALI1563_SMBBA, &ctrl);
337
338	/* SMB I/O Base in high 12 bits and must be aligned with the
339	 * size of the I/O space. */
340	ali1563_smba = ctrl & ~(ALI1563_SMB_IOSIZE - 1);
341	if (!ali1563_smba) {
342		dev_warn(&dev->dev, "ali1563_smba Uninitialized\n");
343		goto Err;
344	}
345
346	/* Check if device is enabled */
347	if (!(ctrl & ALI1563_SMB_HOSTEN)) {
348		dev_warn(&dev->dev, "Host Controller not enabled\n");
349		goto Err;
350	}
351	if (!(ctrl & ALI1563_SMB_IOEN)) {
352		dev_warn(&dev->dev, "I/O space not enabled, trying manually\n");
353		pci_write_config_word(dev, ALI1563_SMBBA,
354				      ctrl | ALI1563_SMB_IOEN);
355		pci_read_config_word(dev, ALI1563_SMBBA, &ctrl);
356		if (!(ctrl & ALI1563_SMB_IOEN)) {
357			dev_err(&dev->dev,
358				"I/O space still not enabled, giving up\n");
359			goto Err;
360		}
361	}
362
363	if (acpi_check_region(ali1563_smba, ALI1563_SMB_IOSIZE,
364			      ali1563_pci_driver.name))
365		goto Err;
366
367	if (!request_region(ali1563_smba, ALI1563_SMB_IOSIZE,
368			    ali1563_pci_driver.name)) {
369		dev_err(&dev->dev, "Could not allocate I/O space at 0x%04x\n",
370			ali1563_smba);
371		goto Err;
372	}
373	dev_info(&dev->dev, "Found ALi1563 SMBus at 0x%04x\n", ali1563_smba);
374
375	return 0;
376Err:
377	return -ENODEV;
378}
379
380static void ali1563_shutdown(struct pci_dev *dev)
381{
382	release_region(ali1563_smba, ALI1563_SMB_IOSIZE);
383}
384
385static const struct i2c_algorithm ali1563_algorithm = {
386	.smbus_xfer	= ali1563_access,
387	.functionality	= ali1563_func,
388};
389
390static struct i2c_adapter ali1563_adapter = {
391	.owner	= THIS_MODULE,
392	.class	= I2C_CLASS_HWMON,
393	.algo	= &ali1563_algorithm,
394};
395
396static int ali1563_probe(struct pci_dev *dev,
397			 const struct pci_device_id *id_table)
398{
399	int error;
400
401	error = ali1563_setup(dev);
402	if (error)
403		goto exit;
404	ali1563_adapter.dev.parent = &dev->dev;
405	snprintf(ali1563_adapter.name, sizeof(ali1563_adapter.name),
406		 "SMBus ALi 1563 Adapter @ %04x", ali1563_smba);
407	error = i2c_add_adapter(&ali1563_adapter);
408	if (error)
409		goto exit_shutdown;
410	return 0;
411
412exit_shutdown:
413	ali1563_shutdown(dev);
414exit:
415	dev_warn(&dev->dev, "ALi1563 SMBus probe failed (%d)\n", error);
416	return error;
417}
418
419static void ali1563_remove(struct pci_dev *dev)
420{
421	i2c_del_adapter(&ali1563_adapter);
422	ali1563_shutdown(dev);
423}
424
425static const struct pci_device_id ali1563_id_table[] = {
426	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1563) },
427	{},
428};
429
430MODULE_DEVICE_TABLE(pci, ali1563_id_table);
431
432static struct pci_driver ali1563_pci_driver = {
433	.name		= "ali1563_smbus",
434	.id_table	= ali1563_id_table,
435	.probe		= ali1563_probe,
436	.remove		= ali1563_remove,
437};
438
439module_pci_driver(ali1563_pci_driver);
440
441MODULE_DESCRIPTION("i2c driver for the ALi 1563 Southbridge");
442MODULE_LICENSE("GPL");