summaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-voodoo3.c
blob: b675773b0cc1d19a9222b87fd319027b4bfef773 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
/*
    voodoo3.c - Part of lm_sensors, Linux kernel modules for hardware
              monitoring
    Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>,
    Philip Edelbrock <phil@netroedge.com>,
    Ralph Metzler <rjkm@thp.uni-koeln.de>, and
    Mark D. Studebaker <mdsxyz123@yahoo.com>
    
    Based on code written by Ralph Metzler <rjkm@thp.uni-koeln.de> and
    Simon Vogl

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/* This interfaces to the I2C bus of the Voodoo3 to gain access to
    the BT869 and possibly other I2C devices. */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
#include <asm/io.h>

/* the only registers we use */
#define REG		0x78
#define REG2 		0x70

/* bit locations in the register */
#define DDC_ENAB	0x00040000
#define DDC_SCL_OUT	0x00080000
#define DDC_SDA_OUT	0x00100000
#define DDC_SCL_IN	0x00200000
#define DDC_SDA_IN	0x00400000
#define I2C_ENAB	0x00800000
#define I2C_SCL_OUT	0x01000000
#define I2C_SDA_OUT	0x02000000
#define I2C_SCL_IN	0x04000000
#define I2C_SDA_IN	0x08000000

/* initialization states */
#define INIT2		0x2
#define INIT3		0x4

/* delays */
#define CYCLE_DELAY	10
#define TIMEOUT		(HZ / 2)


static void __iomem *ioaddr;

/* The voo GPIO registers don't have individual masks for each bit
   so we always have to read before writing. */

static void bit_vooi2c_setscl(void *data, int val)
{
	unsigned int r;
	r = readl(ioaddr + REG);
	if (val)
		r |= I2C_SCL_OUT;
	else
		r &= ~I2C_SCL_OUT;
	writel(r, ioaddr + REG);
	readl(ioaddr + REG);	/* flush posted write */
}

static void bit_vooi2c_setsda(void *data, int val)
{
	unsigned int r;
	r = readl(ioaddr + REG);
	if (val)
		r |= I2C_SDA_OUT;
	else
		r &= ~I2C_SDA_OUT;
	writel(r, ioaddr + REG);
	readl(ioaddr + REG);	/* flush posted write */
}

/* The GPIO pins are open drain, so the pins always remain outputs.
   We rely on the i2c-algo-bit routines to set the pins high before
   reading the input from other chips. */

static int bit_vooi2c_getscl(void *data)
{
	return (0 != (readl(ioaddr + REG) & I2C_SCL_IN));
}

static int bit_vooi2c_getsda(void *data)
{
	return (0 != (readl(ioaddr + REG) & I2C_SDA_IN));
}

static void bit_vooddc_setscl(void *data, int val)
{
	unsigned int r;
	r = readl(ioaddr + REG);
	if (val)
		r |= DDC_SCL_OUT;
	else
		r &= ~DDC_SCL_OUT;
	writel(r, ioaddr + REG);
	readl(ioaddr + REG);	/* flush posted write */
}

static void bit_vooddc_setsda(void *data, int val)
{
	unsigned int r;
	r = readl(ioaddr + REG);
	if (val)
		r |= DDC_SDA_OUT;
	else
		r &= ~DDC_SDA_OUT;
	writel(r, ioaddr + REG);
	readl(ioaddr + REG);	/* flush posted write */
}

static int bit_vooddc_getscl(void *data)
{
	return (0 != (readl(ioaddr + REG) & DDC_SCL_IN));
}

static int bit_vooddc_getsda(void *data)
{
	return (0 != (readl(ioaddr + REG) & DDC_SDA_IN));
}

static int config_v3(struct pci_dev *dev)
{
	unsigned long cadr;

	/* map Voodoo3 memory */
	cadr = dev->resource[0].start;
	cadr &= PCI_BASE_ADDRESS_MEM_MASK;
	ioaddr = ioremap_nocache(cadr, 0x1000);
	if (ioaddr) {
		writel(0x8160, ioaddr + REG2);
		writel(0xcffc0020, ioaddr + REG);
		dev_info(&dev->dev, "Using Banshee/Voodoo3 I2C device at %p\n", ioaddr);
		return 0;
	}
	return -ENODEV;
}

static struct i2c_algo_bit_data voo_i2c_bit_data = {
	.setsda		= bit_vooi2c_setsda,
	.setscl		= bit_vooi2c_setscl,
	.getsda		= bit_vooi2c_getsda,
	.getscl		= bit_vooi2c_getscl,
	.udelay		= CYCLE_DELAY,
	.mdelay		= CYCLE_DELAY,
	.timeout	= TIMEOUT
};

static struct i2c_adapter voodoo3_i2c_adapter = {
	.owner		= THIS_MODULE,
	.class		= I2C_CLASS_TV_ANALOG, 
	.name		= "I2C Voodoo3/Banshee adapter",
	.algo_data	= &voo_i2c_bit_data,
};

static struct i2c_algo_bit_data voo_ddc_bit_data = {
	.setsda		= bit_vooddc_setsda,
	.setscl		= bit_vooddc_setscl,
	.getsda		= bit_vooddc_getsda,
	.getscl		= bit_vooddc_getscl,
	.udelay		= CYCLE_DELAY,
	.mdelay		= CYCLE_DELAY,
	.timeout	= TIMEOUT
};

static struct i2c_adapter voodoo3_ddc_adapter = {
	.owner		= THIS_MODULE,
	.class		= I2C_CLASS_DDC, 
	.name		= "DDC Voodoo3/Banshee adapter",
	.algo_data	= &voo_ddc_bit_data,
};

static struct pci_device_id voodoo3_ids[] __devinitdata = {
	{ PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_VOODOO3) },
	{ PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_BANSHEE) },
	{ 0, }
};

MODULE_DEVICE_TABLE (pci, voodoo3_ids);

static int __devinit voodoo3_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	int retval;

	retval = config_v3(dev);
	if (retval)
		return retval;

	/* set up the sysfs linkage to our parent device */
	voodoo3_i2c_adapter.dev.parent = &dev->dev;
	voodoo3_ddc_adapter.dev.parent = &dev->dev;

	retval = i2c_bit_add_bus(&voodoo3_i2c_adapter);
	if (retval)
		return retval;
	retval = i2c_bit_add_bus(&voodoo3_ddc_adapter);
	if (retval)
		i2c_bit_del_bus(&voodoo3_i2c_adapter);
	return retval;
}

static void __devexit voodoo3_remove(struct pci_dev *dev)
{
	i2c_bit_del_bus(&voodoo3_i2c_adapter);
 	i2c_bit_del_bus(&voodoo3_ddc_adapter);
	iounmap(ioaddr);
}

static struct pci_driver voodoo3_driver = {
	.name		= "voodoo3_smbus",
	.id_table	= voodoo3_ids,
	.probe		= voodoo3_probe,
	.remove		= __devexit_p(voodoo3_remove),
};

static int __init i2c_voodoo3_init(void)
{
	return pci_register_driver(&voodoo3_driver);
}

static void __exit i2c_voodoo3_exit(void)
{
	pci_unregister_driver(&voodoo3_driver);
}


MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
		"Philip Edelbrock <phil@netroedge.com>, "
		"Ralph Metzler <rjkm@thp.uni-koeln.de>, "
		"and Mark D. Studebaker <mdsxyz123@yahoo.com>");
MODULE_DESCRIPTION("Voodoo3 I2C/SMBus driver");
MODULE_LICENSE("GPL");

module_init(i2c_voodoo3_init);
module_exit(i2c_voodoo3_exit);