Linux 2.6.31-rc6
[linux-2.6] / drivers / i2c / busses / i2c-voodoo3.c
1 /*
2     Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>,
3     Philip Edelbrock <phil@netroedge.com>,
4     Ralph Metzler <rjkm@thp.uni-koeln.de>, and
5     Mark D. Studebaker <mdsxyz123@yahoo.com>
6     
7     Based on code written by Ralph Metzler <rjkm@thp.uni-koeln.de> and
8     Simon Vogl
9
10     This program is free software; you can redistribute it and/or modify
11     it under the terms of the GNU General Public License as published by
12     the Free Software Foundation; either version 2 of the License, or
13     (at your option) any later version.
14
15     This program is distributed in the hope that it will be useful,
16     but WITHOUT ANY WARRANTY; without even the implied warranty of
17     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18     GNU General Public License for more details.
19
20     You should have received a copy of the GNU General Public License
21     along with this program; if not, write to the Free Software
22     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25 /* This interfaces to the I2C bus of the Voodoo3 to gain access to
26     the BT869 and possibly other I2C devices. */
27
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/pci.h>
32 #include <linux/i2c.h>
33 #include <linux/i2c-algo-bit.h>
34 #include <asm/io.h>
35
36 /* the only registers we use */
37 #define REG             0x78
38 #define REG2            0x70
39
40 /* bit locations in the register */
41 #define DDC_ENAB        0x00040000
42 #define DDC_SCL_OUT     0x00080000
43 #define DDC_SDA_OUT     0x00100000
44 #define DDC_SCL_IN      0x00200000
45 #define DDC_SDA_IN      0x00400000
46 #define I2C_ENAB        0x00800000
47 #define I2C_SCL_OUT     0x01000000
48 #define I2C_SDA_OUT     0x02000000
49 #define I2C_SCL_IN      0x04000000
50 #define I2C_SDA_IN      0x08000000
51
52 /* initialization states */
53 #define INIT2           0x2
54 #define INIT3           0x4
55
56 /* delays */
57 #define CYCLE_DELAY     10
58 #define TIMEOUT         (HZ / 2)
59
60
61 static void __iomem *ioaddr;
62
63 /* The voo GPIO registers don't have individual masks for each bit
64    so we always have to read before writing. */
65
66 static void bit_vooi2c_setscl(void *data, int val)
67 {
68         unsigned int r;
69         r = readl(ioaddr + REG);
70         if (val)
71                 r |= I2C_SCL_OUT;
72         else
73                 r &= ~I2C_SCL_OUT;
74         writel(r, ioaddr + REG);
75         readl(ioaddr + REG);    /* flush posted write */
76 }
77
78 static void bit_vooi2c_setsda(void *data, int val)
79 {
80         unsigned int r;
81         r = readl(ioaddr + REG);
82         if (val)
83                 r |= I2C_SDA_OUT;
84         else
85                 r &= ~I2C_SDA_OUT;
86         writel(r, ioaddr + REG);
87         readl(ioaddr + REG);    /* flush posted write */
88 }
89
90 /* The GPIO pins are open drain, so the pins always remain outputs.
91    We rely on the i2c-algo-bit routines to set the pins high before
92    reading the input from other chips. */
93
94 static int bit_vooi2c_getscl(void *data)
95 {
96         return (0 != (readl(ioaddr + REG) & I2C_SCL_IN));
97 }
98
99 static int bit_vooi2c_getsda(void *data)
100 {
101         return (0 != (readl(ioaddr + REG) & I2C_SDA_IN));
102 }
103
104 static void bit_vooddc_setscl(void *data, int val)
105 {
106         unsigned int r;
107         r = readl(ioaddr + REG);
108         if (val)
109                 r |= DDC_SCL_OUT;
110         else
111                 r &= ~DDC_SCL_OUT;
112         writel(r, ioaddr + REG);
113         readl(ioaddr + REG);    /* flush posted write */
114 }
115
116 static void bit_vooddc_setsda(void *data, int val)
117 {
118         unsigned int r;
119         r = readl(ioaddr + REG);
120         if (val)
121                 r |= DDC_SDA_OUT;
122         else
123                 r &= ~DDC_SDA_OUT;
124         writel(r, ioaddr + REG);
125         readl(ioaddr + REG);    /* flush posted write */
126 }
127
128 static int bit_vooddc_getscl(void *data)
129 {
130         return (0 != (readl(ioaddr + REG) & DDC_SCL_IN));
131 }
132
133 static int bit_vooddc_getsda(void *data)
134 {
135         return (0 != (readl(ioaddr + REG) & DDC_SDA_IN));
136 }
137
138 static int config_v3(struct pci_dev *dev)
139 {
140         unsigned long cadr;
141
142         /* map Voodoo3 memory */
143         cadr = dev->resource[0].start;
144         cadr &= PCI_BASE_ADDRESS_MEM_MASK;
145         ioaddr = ioremap_nocache(cadr, 0x1000);
146         if (ioaddr) {
147                 writel(0x8160, ioaddr + REG2);
148                 writel(0xcffc0020, ioaddr + REG);
149                 dev_info(&dev->dev, "Using Banshee/Voodoo3 I2C device at %p\n", ioaddr);
150                 return 0;
151         }
152         return -ENODEV;
153 }
154
155 static struct i2c_algo_bit_data voo_i2c_bit_data = {
156         .setsda         = bit_vooi2c_setsda,
157         .setscl         = bit_vooi2c_setscl,
158         .getsda         = bit_vooi2c_getsda,
159         .getscl         = bit_vooi2c_getscl,
160         .udelay         = CYCLE_DELAY,
161         .timeout        = TIMEOUT
162 };
163
164 static struct i2c_adapter voodoo3_i2c_adapter = {
165         .owner          = THIS_MODULE,
166         .name           = "I2C Voodoo3/Banshee adapter",
167         .algo_data      = &voo_i2c_bit_data,
168 };
169
170 static struct i2c_algo_bit_data voo_ddc_bit_data = {
171         .setsda         = bit_vooddc_setsda,
172         .setscl         = bit_vooddc_setscl,
173         .getsda         = bit_vooddc_getsda,
174         .getscl         = bit_vooddc_getscl,
175         .udelay         = CYCLE_DELAY,
176         .timeout        = TIMEOUT
177 };
178
179 static struct i2c_adapter voodoo3_ddc_adapter = {
180         .owner          = THIS_MODULE,
181         .class          = I2C_CLASS_DDC, 
182         .name           = "DDC Voodoo3/Banshee adapter",
183         .algo_data      = &voo_ddc_bit_data,
184 };
185
186 static struct pci_device_id voodoo3_ids[] __devinitdata = {
187         { PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_VOODOO3) },
188         { PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_BANSHEE) },
189         { 0, }
190 };
191
192 MODULE_DEVICE_TABLE (pci, voodoo3_ids);
193
194 static int __devinit voodoo3_probe(struct pci_dev *dev, const struct pci_device_id *id)
195 {
196         int retval;
197
198         retval = config_v3(dev);
199         if (retval)
200                 return retval;
201
202         /* set up the sysfs linkage to our parent device */
203         voodoo3_i2c_adapter.dev.parent = &dev->dev;
204         voodoo3_ddc_adapter.dev.parent = &dev->dev;
205
206         retval = i2c_bit_add_bus(&voodoo3_i2c_adapter);
207         if (retval)
208                 return retval;
209         retval = i2c_bit_add_bus(&voodoo3_ddc_adapter);
210         if (retval)
211                 i2c_del_adapter(&voodoo3_i2c_adapter);
212         return retval;
213 }
214
215 static void __devexit voodoo3_remove(struct pci_dev *dev)
216 {
217         i2c_del_adapter(&voodoo3_i2c_adapter);
218         i2c_del_adapter(&voodoo3_ddc_adapter);
219         iounmap(ioaddr);
220 }
221
222 static struct pci_driver voodoo3_driver = {
223         .name           = "voodoo3_smbus",
224         .id_table       = voodoo3_ids,
225         .probe          = voodoo3_probe,
226         .remove         = __devexit_p(voodoo3_remove),
227 };
228
229 static int __init i2c_voodoo3_init(void)
230 {
231         return pci_register_driver(&voodoo3_driver);
232 }
233
234 static void __exit i2c_voodoo3_exit(void)
235 {
236         pci_unregister_driver(&voodoo3_driver);
237 }
238
239
240 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
241                 "Philip Edelbrock <phil@netroedge.com>, "
242                 "Ralph Metzler <rjkm@thp.uni-koeln.de>, "
243                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
244 MODULE_DESCRIPTION("Voodoo3 I2C/SMBus driver");
245 MODULE_LICENSE("GPL");
246
247 module_init(i2c_voodoo3_init);
248 module_exit(i2c_voodoo3_exit);