aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/video/i810/i810-i2c.c
blob: 961f4d40446799ac1fdcbec9f15e533f2ee2abc5 (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
 /*-*- linux-c -*-
 *  linux/drivers/video/i810-i2c.c -- Intel 810/815 I2C support
 *
 *      Copyright (C) 2004 Antonino Daplas<adaplas@pol.net>
 *      All Rights Reserved
 *
 *  This file is subject to the terms and conditions of the GNU General Public
 *  License. See the file COPYING in the main directory of this archive for
 *  more details.
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/fb.h>
#include "i810.h"
#include "i810_regs.h"
#include "i810_main.h"
#include "../edid.h"

/* bit locations in the registers */
#define SCL_DIR_MASK		0x0001
#define SCL_DIR			0x0002
#define SCL_VAL_MASK		0x0004
#define SCL_VAL_OUT		0x0008
#define SCL_VAL_IN		0x0010
#define SDA_DIR_MASK		0x0100
#define SDA_DIR			0x0200
#define SDA_VAL_MASK		0x0400
#define SDA_VAL_OUT		0x0800
#define SDA_VAL_IN		0x1000

#define DEBUG  /* define this for verbose EDID parsing output */

#ifdef DEBUG
#define DPRINTK(fmt, args...) printk(fmt,## args)
#else
#define DPRINTK(fmt, args...)
#endif

static void i810i2c_setscl(void *data, int state)
{
        struct i810fb_i2c_chan    *chan = data;
        struct i810fb_par         *par = chan->par;
	u8                        __iomem *mmio = par->mmio_start_virtual;

	i810_writel(mmio, chan->ddc_base, (state ? SCL_VAL_OUT : 0) | SCL_DIR |
		    SCL_DIR_MASK | SCL_VAL_MASK);
	i810_readl(mmio, chan->ddc_base);	/* flush posted write */
}

static void i810i2c_setsda(void *data, int state)
{
        struct i810fb_i2c_chan    *chan = data;
        struct i810fb_par         *par = chan->par;
	u8                        __iomem *mmio = par->mmio_start_virtual;

 	i810_writel(mmio, chan->ddc_base, (state ? SDA_VAL_OUT : 0) | SDA_DIR |
		    SDA_DIR_MASK | SDA_VAL_MASK);
	i810_readl(mmio, chan->ddc_base);	/* flush posted write */
}

static int i810i2c_getscl(void *data)
{
        struct i810fb_i2c_chan    *chan = data;
        struct i810fb_par         *par = chan->par;
	u8                        __iomem *mmio = par->mmio_start_virtual;

	i810_writel(mmio, chan->ddc_base, SCL_DIR_MASK);
	i810_writel(mmio, chan->ddc_base, 0);
	return ((i810_readl(mmio, chan->ddc_base) & SCL_VAL_IN) != 0);
}

static int i810i2c_getsda(void *data)
{
        struct i810fb_i2c_chan    *chan = data;
        struct i810fb_par         *par = chan->par;
	u8                        __iomem *mmio = par->mmio_start_virtual;

	i810_writel(mmio, chan->ddc_base, SDA_DIR_MASK);
	i810_writel(mmio, chan->ddc_base, 0);
	return ((i810_readl(mmio, chan->ddc_base) & SDA_VAL_IN) != 0);
}

static int i810_setup_i2c_bus(struct i810fb_i2c_chan *chan, const char *name)
{
        int rc;

        strcpy(chan->adapter.name, name);
        chan->adapter.owner             = THIS_MODULE;
        chan->adapter.algo_data         = &chan->algo;
        chan->adapter.dev.parent        = &chan->par->dev->dev;
	chan->adapter.id                = I2C_HW_B_I810;
	chan->algo.setsda               = i810i2c_setsda;
	chan->algo.setscl               = i810i2c_setscl;
	chan->algo.getsda               = i810i2c_getsda;
	chan->algo.getscl               = i810i2c_getscl;
	chan->algo.udelay               = 10;
        chan->algo.timeout              = (HZ/2);
        chan->algo.data                 = chan;

        i2c_set_adapdata(&chan->adapter, chan);

        /* Raise SCL and SDA */
        chan->algo.setsda(chan, 1);
        chan->algo.setscl(chan, 1);
        udelay(20);

        rc = i2c_bit_add_bus(&chan->adapter);

        if (rc == 0)
                dev_dbg(&chan->par->dev->dev, "I2C bus %s registered.\n",name);
        else {
                dev_warn(&chan->par->dev->dev, "Failed to register I2C bus "
			 "%s.\n", name);
		chan->par = NULL;
	}

        return rc;
}

void i810_create_i2c_busses(struct i810fb_par *par)
{
        par->chan[0].par        = par;
	par->chan[1].par        = par;
	par->chan[2].par        = par;

	par->chan[0].ddc_base = GPIOA;
	i810_setup_i2c_bus(&par->chan[0], "I810-DDC");
	par->chan[1].ddc_base = GPIOB;
	i810_setup_i2c_bus(&par->chan[1], "I810-I2C");
	par->chan[2].ddc_base = GPIOC;
	i810_setup_i2c_bus(&par->chan[2], "I810-GPIOC");
}

void i810_delete_i2c_busses(struct i810fb_par *par)
{
        if (par->chan[0].par)
		i2c_del_adapter(&par->chan[0].adapter);
        par->chan[0].par = NULL;

	if (par->chan[1].par)
		i2c_del_adapter(&par->chan[1].adapter);
	par->chan[1].par = NULL;

	if (par->chan[2].par)
		i2c_del_adapter(&par->chan[2].adapter);
	par->chan[2].par = NULL;
}

int i810_probe_i2c_connector(struct fb_info *info, u8 **out_edid, int conn)
{
	struct i810fb_par *par = info->par;
        u8 *edid = NULL;

	DPRINTK("i810-i2c: Probe DDC%i Bus\n", conn+1);
	if (conn < par->ddc_num) {
		edid = fb_ddc_read(&par->chan[conn].adapter);
	} else {
		const u8 *e = fb_firmware_edid(info->device);

		if (e != NULL) {
			DPRINTK("i810-i2c: Getting EDID from BIOS\n");
			edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);
		}
	}

	*out_edid = edid;

        return (edid) ? 0 : 1;
}