1 /*
2 * linux/drivers/video/nvidia/nvidia-i2c.c - nVidia i2c
3 *
4 * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
5 *
6 * Based on rivafb-i2c.c
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file COPYING in the main directory of this archive
10 * for more details.
11 */
12
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/delay.h>
16 #include <linux/gfp.h>
17 #include <linux/pci.h>
18 #include <linux/fb.h>
19
20 #include <asm/io.h>
21
22 #include "nv_type.h"
23 #include "nv_local.h"
24 #include "nv_proto.h"
25
26 #include "../edid.h"
27
nvidia_gpio_setscl(void * data,int state)28 static void nvidia_gpio_setscl(void *data, int state)
29 {
30 struct nvidia_i2c_chan *chan = data;
31 struct nvidia_par *par = chan->par;
32 u32 val;
33
34 val = NVReadCrtc(par, chan->ddc_base + 1) & 0xf0;
35
36 if (state)
37 val |= 0x20;
38 else
39 val &= ~0x20;
40
41 NVWriteCrtc(par, chan->ddc_base + 1, val | 0x01);
42 }
43
nvidia_gpio_setsda(void * data,int state)44 static void nvidia_gpio_setsda(void *data, int state)
45 {
46 struct nvidia_i2c_chan *chan = data;
47 struct nvidia_par *par = chan->par;
48 u32 val;
49
50 val = NVReadCrtc(par, chan->ddc_base + 1) & 0xf0;
51
52 if (state)
53 val |= 0x10;
54 else
55 val &= ~0x10;
56
57 NVWriteCrtc(par, chan->ddc_base + 1, val | 0x01);
58 }
59
nvidia_gpio_getscl(void * data)60 static int nvidia_gpio_getscl(void *data)
61 {
62 struct nvidia_i2c_chan *chan = data;
63 struct nvidia_par *par = chan->par;
64 u32 val = 0;
65
66 if (NVReadCrtc(par, chan->ddc_base) & 0x04)
67 val = 1;
68
69 return val;
70 }
71
nvidia_gpio_getsda(void * data)72 static int nvidia_gpio_getsda(void *data)
73 {
74 struct nvidia_i2c_chan *chan = data;
75 struct nvidia_par *par = chan->par;
76 u32 val = 0;
77
78 if (NVReadCrtc(par, chan->ddc_base) & 0x08)
79 val = 1;
80
81 return val;
82 }
83
nvidia_setup_i2c_bus(struct nvidia_i2c_chan * chan,const char * name,unsigned int i2c_class)84 static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name,
85 unsigned int i2c_class)
86 {
87 int rc;
88
89 strscpy(chan->adapter.name, name, sizeof(chan->adapter.name));
90 chan->adapter.owner = THIS_MODULE;
91 chan->adapter.class = i2c_class;
92 chan->adapter.algo_data = &chan->algo;
93 chan->adapter.dev.parent = &chan->par->pci_dev->dev;
94 chan->algo.setsda = nvidia_gpio_setsda;
95 chan->algo.setscl = nvidia_gpio_setscl;
96 chan->algo.getsda = nvidia_gpio_getsda;
97 chan->algo.getscl = nvidia_gpio_getscl;
98 chan->algo.udelay = 40;
99 chan->algo.timeout = msecs_to_jiffies(2);
100 chan->algo.data = chan;
101
102 i2c_set_adapdata(&chan->adapter, chan);
103
104 /* Raise SCL and SDA */
105 nvidia_gpio_setsda(chan, 1);
106 nvidia_gpio_setscl(chan, 1);
107 udelay(20);
108
109 rc = i2c_bit_add_bus(&chan->adapter);
110 if (rc == 0)
111 dev_dbg(&chan->par->pci_dev->dev,
112 "I2C bus %s registered.\n", name);
113 else {
114 dev_warn(&chan->par->pci_dev->dev,
115 "Failed to register I2C bus %s.\n", name);
116 chan->par = NULL;
117 }
118
119 return rc;
120 }
121
nvidia_create_i2c_busses(struct nvidia_par * par)122 void nvidia_create_i2c_busses(struct nvidia_par *par)
123 {
124 par->chan[0].par = par;
125 par->chan[1].par = par;
126 par->chan[2].par = par;
127
128 par->chan[0].ddc_base = (par->reverse_i2c) ? 0x36 : 0x3e;
129 nvidia_setup_i2c_bus(&par->chan[0], "nvidia #0",
130 (par->reverse_i2c) ? I2C_CLASS_HWMON : 0);
131
132 par->chan[1].ddc_base = (par->reverse_i2c) ? 0x3e : 0x36;
133 nvidia_setup_i2c_bus(&par->chan[1], "nvidia #1",
134 (par->reverse_i2c) ? 0 : I2C_CLASS_HWMON);
135
136 par->chan[2].ddc_base = 0x50;
137 nvidia_setup_i2c_bus(&par->chan[2], "nvidia #2", 0);
138 }
139
nvidia_delete_i2c_busses(struct nvidia_par * par)140 void nvidia_delete_i2c_busses(struct nvidia_par *par)
141 {
142 int i;
143
144 for (i = 0; i < 3; i++) {
145 if (!par->chan[i].par)
146 continue;
147 i2c_del_adapter(&par->chan[i].adapter);
148 par->chan[i].par = NULL;
149 }
150 }
151
nvidia_probe_i2c_connector(struct fb_info * info,int conn,u8 ** out_edid)152 int nvidia_probe_i2c_connector(struct fb_info *info, int conn, u8 **out_edid)
153 {
154 struct nvidia_par *par = info->par;
155 u8 *edid = NULL;
156
157 if (par->chan[conn - 1].par)
158 edid = fb_ddc_read(&par->chan[conn - 1].adapter);
159
160 if (!edid && conn == 1) {
161 /* try to get from firmware */
162 const u8 *e = fb_firmware_edid(info->device);
163
164 if (e != NULL)
165 edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);
166 }
167
168 *out_edid = edid;
169
170 return (edid) ? 0 : 1;
171 }
172