Merge git://git.infradead.org/mtd-2.6
[linux-2.6] / drivers / video / i810 / i810-i2c.c
1  /*-*- linux-c -*-
2  *  linux/drivers/video/i810-i2c.c -- Intel 810/815 I2C support
3  *
4  *      Copyright (C) 2004 Antonino Daplas<adaplas@pol.net>
5  *      All Rights Reserved
6  *
7  *  This file is subject to the terms and conditions of the GNU General Public
8  *  License. See the file COPYING in the main directory of this archive for
9  *  more details.
10  */
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/delay.h>
14 #include <linux/pci.h>
15 #include <linux/fb.h>
16 #include "i810.h"
17 #include "i810_regs.h"
18 #include "i810_main.h"
19 #include "../edid.h"
20
21 /* bit locations in the registers */
22 #define SCL_DIR_MASK            0x0001
23 #define SCL_DIR                 0x0002
24 #define SCL_VAL_MASK            0x0004
25 #define SCL_VAL_OUT             0x0008
26 #define SCL_VAL_IN              0x0010
27 #define SDA_DIR_MASK            0x0100
28 #define SDA_DIR                 0x0200
29 #define SDA_VAL_MASK            0x0400
30 #define SDA_VAL_OUT             0x0800
31 #define SDA_VAL_IN              0x1000
32
33 #define DEBUG  /* define this for verbose EDID parsing output */
34
35 #ifdef DEBUG
36 #define DPRINTK(fmt, args...) printk(fmt,## args)
37 #else
38 #define DPRINTK(fmt, args...)
39 #endif
40
41 static void i810i2c_setscl(void *data, int state)
42 {
43         struct i810fb_i2c_chan    *chan = data;
44         struct i810fb_par         *par = chan->par;
45         u8                        __iomem *mmio = par->mmio_start_virtual;
46
47         i810_writel(mmio, chan->ddc_base, (state ? SCL_VAL_OUT : 0) | SCL_DIR |
48                     SCL_DIR_MASK | SCL_VAL_MASK);
49         i810_readl(mmio, chan->ddc_base);       /* flush posted write */
50 }
51
52 static void i810i2c_setsda(void *data, int state)
53 {
54         struct i810fb_i2c_chan    *chan = data;
55         struct i810fb_par         *par = chan->par;
56         u8                        __iomem *mmio = par->mmio_start_virtual;
57
58         i810_writel(mmio, chan->ddc_base, (state ? SDA_VAL_OUT : 0) | SDA_DIR |
59                     SDA_DIR_MASK | SDA_VAL_MASK);
60         i810_readl(mmio, chan->ddc_base);       /* flush posted write */
61 }
62
63 static int i810i2c_getscl(void *data)
64 {
65         struct i810fb_i2c_chan    *chan = data;
66         struct i810fb_par         *par = chan->par;
67         u8                        __iomem *mmio = par->mmio_start_virtual;
68
69         i810_writel(mmio, chan->ddc_base, SCL_DIR_MASK);
70         i810_writel(mmio, chan->ddc_base, 0);
71         return ((i810_readl(mmio, chan->ddc_base) & SCL_VAL_IN) != 0);
72 }
73
74 static int i810i2c_getsda(void *data)
75 {
76         struct i810fb_i2c_chan    *chan = data;
77         struct i810fb_par         *par = chan->par;
78         u8                        __iomem *mmio = par->mmio_start_virtual;
79
80         i810_writel(mmio, chan->ddc_base, SDA_DIR_MASK);
81         i810_writel(mmio, chan->ddc_base, 0);
82         return ((i810_readl(mmio, chan->ddc_base) & SDA_VAL_IN) != 0);
83 }
84
85 static int i810_setup_i2c_bus(struct i810fb_i2c_chan *chan, const char *name)
86 {
87         int rc;
88
89         strcpy(chan->adapter.name, name);
90         chan->adapter.owner             = THIS_MODULE;
91         chan->adapter.algo_data         = &chan->algo;
92         chan->adapter.dev.parent        = &chan->par->dev->dev;
93         chan->algo.setsda               = i810i2c_setsda;
94         chan->algo.setscl               = i810i2c_setscl;
95         chan->algo.getsda               = i810i2c_getsda;
96         chan->algo.getscl               = i810i2c_getscl;
97         chan->algo.udelay               = 10;
98         chan->algo.timeout              = (HZ/2);
99         chan->algo.data                 = chan;
100
101         i2c_set_adapdata(&chan->adapter, chan);
102
103         /* Raise SCL and SDA */
104         chan->algo.setsda(chan, 1);
105         chan->algo.setscl(chan, 1);
106         udelay(20);
107
108         rc = i2c_bit_add_bus(&chan->adapter);
109
110         if (rc == 0)
111                 dev_dbg(&chan->par->dev->dev, "I2C bus %s registered.\n",name);
112         else {
113                 dev_warn(&chan->par->dev->dev, "Failed to register I2C bus "
114                          "%s.\n", name);
115                 chan->par = NULL;
116         }
117
118         return rc;
119 }
120
121 void i810_create_i2c_busses(struct i810fb_par *par)
122 {
123         par->chan[0].par        = par;
124         par->chan[1].par        = par;
125         par->chan[2].par        = par;
126
127         par->chan[0].ddc_base = GPIOA;
128         i810_setup_i2c_bus(&par->chan[0], "I810-DDC");
129         par->chan[1].ddc_base = GPIOB;
130         i810_setup_i2c_bus(&par->chan[1], "I810-I2C");
131         par->chan[2].ddc_base = GPIOC;
132         i810_setup_i2c_bus(&par->chan[2], "I810-GPIOC");
133 }
134
135 void i810_delete_i2c_busses(struct i810fb_par *par)
136 {
137         if (par->chan[0].par)
138                 i2c_del_adapter(&par->chan[0].adapter);
139         par->chan[0].par = NULL;
140
141         if (par->chan[1].par)
142                 i2c_del_adapter(&par->chan[1].adapter);
143         par->chan[1].par = NULL;
144
145         if (par->chan[2].par)
146                 i2c_del_adapter(&par->chan[2].adapter);
147         par->chan[2].par = NULL;
148 }
149
150 int i810_probe_i2c_connector(struct fb_info *info, u8 **out_edid, int conn)
151 {
152         struct i810fb_par *par = info->par;
153         u8 *edid = NULL;
154
155         DPRINTK("i810-i2c: Probe DDC%i Bus\n", conn+1);
156         if (conn < par->ddc_num) {
157                 edid = fb_ddc_read(&par->chan[conn].adapter);
158         } else {
159                 const u8 *e = fb_firmware_edid(info->device);
160
161                 if (e != NULL) {
162                         DPRINTK("i810-i2c: Getting EDID from BIOS\n");
163                         edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);
164                 }
165         }
166
167         *out_edid = edid;
168
169         return (edid) ? 0 : 1;
170 }