summaryrefslogtreecommitdiffstats
path: root/drivers/video/nvidia/nv_i2c.c
blob: 12f2884d3f0bd7da64b6fc37e2042fee4f05f5a6 (plain)
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
/*
 * linux/drivers/video/nvidia/nvidia-i2c.c - nVidia i2c
 *
 * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
 *
 * Based on rivafb-i2c.c
 *
 * 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/config.h>
#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 <asm/io.h>

#include "nv_type.h"
#include "nv_local.h"
#include "nv_proto.h"

#include "../edid.h"

static void nvidia_gpio_setscl(void *data, int state)
{
	struct nvidia_i2c_chan *chan = data;
	struct nvidia_par *par = chan->par;
	u32 val;

	VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
	val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;

	if (state)
		val |= 0x20;
	else
		val &= ~0x20;

	VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
	VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
}

static void nvidia_gpio_setsda(void *data, int state)
{
	struct nvidia_i2c_chan *chan = (struct nvidia_i2c_chan *)data;
	struct nvidia_par *par = chan->par;
	u32 val;

	VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
	val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;

	if (state)
		val |= 0x10;
	else
		val &= ~0x10;

	VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
	VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
}

static int nvidia_gpio_getscl(void *data)
{
	struct nvidia_i2c_chan *chan = (struct nvidia_i2c_chan *)data;
	struct nvidia_par *par = chan->par;
	u32 val = 0;

	VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
	if (VGA_RD08(par->PCIO, 0x3d5) & 0x04)
		val = 1;

	val = VGA_RD08(par->PCIO, 0x3d5);

	return val;
}

static int nvidia_gpio_getsda(void *data)
{
	struct nvidia_i2c_chan *chan = (struct nvidia_i2c_chan *)data;
	struct nvidia_par *par = chan->par;
	u32 val = 0;

	VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
	if (VGA_RD08(par->PCIO, 0x3d5) & 0x08)
		val = 1;

	return val;
}

static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name)
{
	int rc;

	strcpy(chan->adapter.name, name);
	chan->adapter.owner = THIS_MODULE;
	chan->adapter.id = I2C_HW_B_NVIDIA;
	chan->adapter.algo_data = &chan->algo;
	chan->adapter.dev.parent = &chan->par->pci_dev->dev;
	chan->algo.setsda = nvidia_gpio_setsda;
	chan->algo.setscl = nvidia_gpio_setscl;
	chan->algo.getsda = nvidia_gpio_getsda;
	chan->algo.getscl = nvidia_gpio_getscl;
	chan->algo.udelay = 40;
	chan->algo.timeout = msecs_to_jiffies(2);
	chan->algo.data = chan;

	i2c_set_adapdata(&chan->adapter, chan);

	/* Raise SCL and SDA */
	nvidia_gpio_setsda(chan, 1);
	nvidia_gpio_setscl(chan, 1);
	udelay(20);

	rc = i2c_bit_add_bus(&chan->adapter);
	if (rc == 0)
		dev_dbg(&chan->par->pci_dev->dev,
			"I2C bus %s registered.\n", name);
	else {
		dev_warn(&chan->par->pci_dev->dev,
			 "Failed to register I2C bus %s.\n", name);
		chan->par = NULL;
	}

	return rc;
}

void nvidia_create_i2c_busses(struct nvidia_par *par)
{
	par->bus = 3;

	par->chan[0].par = par;
	par->chan[1].par = par;
	par->chan[2].par = par;

	par->chan[0].ddc_base = 0x3e;
	nvidia_setup_i2c_bus(&par->chan[0], "BUS1");

	par->chan[1].ddc_base = 0x36;
	nvidia_setup_i2c_bus(&par->chan[1], "BUS2");

	par->chan[2].ddc_base = 0x50;
	nvidia_setup_i2c_bus(&par->chan[2], "BUS3");
}

void nvidia_delete_i2c_busses(struct nvidia_par *par)
{
	if (par->chan[0].par)
		i2c_bit_del_bus(&par->chan[0].adapter);
	par->chan[0].par = NULL;

	if (par->chan[1].par)
		i2c_bit_del_bus(&par->chan[1].adapter);
	par->chan[1].par = NULL;

	if (par->chan[2].par)
		i2c_bit_del_bus(&par->chan[2].adapter);
	par->chan[2].par = NULL;

}

static u8 *nvidia_do_probe_i2c_edid(struct nvidia_i2c_chan *chan)
{
	u8 start = 0x0;
	struct i2c_msg msgs[] = {
		{
		 .addr = 0x50,
		 .len = 1,
		 .buf = &start,
		 }, {
		     .addr = 0x50,
		     .flags = I2C_M_RD,
		     .len = EDID_LENGTH,
		     },
	};
	u8 *buf;

	if (!chan->par)
		return NULL;

	buf = kmalloc(EDID_LENGTH, GFP_KERNEL);
	if (!buf) {
		dev_warn(&chan->par->pci_dev->dev, "Out of memory!\n");
		return NULL;
	}
	msgs[1].buf = buf;

	if (i2c_transfer(&chan->adapter, msgs, 2) == 2)
		return buf;
	dev_dbg(&chan->par->pci_dev->dev, "Unable to read EDID block.\n");
	kfree(buf);
	return NULL;
}

int nvidia_probe_i2c_connector(struct fb_info *info, int conn, u8 **out_edid)
{
	struct nvidia_par *par = info->par;
	u8 *edid = NULL;
	int i;

	for (i = 0; i < 3; i++) {
		/* Do the real work */
		edid = nvidia_do_probe_i2c_edid(&par->chan[conn - 1]);
		if (edid)
			break;
	}

	if (!edid && conn == 1) {
		/* try to get from firmware */
		const u8 *e = fb_firmware_edid(info->device);

		if (e != NULL) {
			edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
			if (edid)
				memcpy(edid, e, EDID_LENGTH);
		}
	}

	if (out_edid)
		*out_edid = edid;

	return (edid) ? 0 : 1;
}