1/*
2 * linux/drivers/video/savage/savagefb-i2c.c - S3 Savage DDC2
3 *
4 * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
5 *
6 * Based partly 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#include "savagefb.h"
22
23#define SAVAGE_DDC 0x50
24
25#define VGA_CR_IX 0x3d4
26#define VGA_CR_DATA 0x3d5
27
28#define CR_SERIAL1 0xa0 /* I2C serial communications interface */
29#define MM_SERIAL1 0xff20
30#define CR_SERIAL2 0xb1 /* DDC2 monitor communications interface */
31
32/* based on vt8365 documentation */
33#define PROSAVAGE_I2C_ENAB 0x10
34#define PROSAVAGE_I2C_SCL_OUT 0x01
35#define PROSAVAGE_I2C_SDA_OUT 0x02
36#define PROSAVAGE_I2C_SCL_IN 0x04
37#define PROSAVAGE_I2C_SDA_IN 0x08
38
39#define SAVAGE4_I2C_ENAB 0x00000020
40#define SAVAGE4_I2C_SCL_OUT 0x00000001
41#define SAVAGE4_I2C_SDA_OUT 0x00000002
42#define SAVAGE4_I2C_SCL_IN 0x00000008
43#define SAVAGE4_I2C_SDA_IN 0x00000010
44
45static void savage4_gpio_setscl(void *data, int val)
46{
47 struct savagefb_i2c_chan *chan = data;
48 unsigned int r;
49
50 r = readl(addr: chan->ioaddr + chan->reg);
51 if(val)
52 r |= SAVAGE4_I2C_SCL_OUT;
53 else
54 r &= ~SAVAGE4_I2C_SCL_OUT;
55 writel(val: r, addr: chan->ioaddr + chan->reg);
56 readl(addr: chan->ioaddr + chan->reg); /* flush posted write */
57}
58
59static void savage4_gpio_setsda(void *data, int val)
60{
61 struct savagefb_i2c_chan *chan = data;
62
63 unsigned int r;
64 r = readl(addr: chan->ioaddr + chan->reg);
65 if(val)
66 r |= SAVAGE4_I2C_SDA_OUT;
67 else
68 r &= ~SAVAGE4_I2C_SDA_OUT;
69 writel(val: r, addr: chan->ioaddr + chan->reg);
70 readl(addr: chan->ioaddr + chan->reg); /* flush posted write */
71}
72
73static int savage4_gpio_getscl(void *data)
74{
75 struct savagefb_i2c_chan *chan = data;
76
77 return (0 != (readl(addr: chan->ioaddr + chan->reg) & SAVAGE4_I2C_SCL_IN));
78}
79
80static int savage4_gpio_getsda(void *data)
81{
82 struct savagefb_i2c_chan *chan = data;
83
84 return (0 != (readl(addr: chan->ioaddr + chan->reg) & SAVAGE4_I2C_SDA_IN));
85}
86
87static void prosavage_gpio_setscl(void* data, int val)
88{
89 struct savagefb_i2c_chan *chan = data;
90 u32 r;
91
92 r = VGArCR(index: chan->reg, par: chan->par);
93 r |= PROSAVAGE_I2C_ENAB;
94 if (val) {
95 r |= PROSAVAGE_I2C_SCL_OUT;
96 } else {
97 r &= ~PROSAVAGE_I2C_SCL_OUT;
98 }
99
100 VGAwCR(index: chan->reg, val: r, par: chan->par);
101}
102
103static void prosavage_gpio_setsda(void* data, int val)
104{
105 struct savagefb_i2c_chan *chan = data;
106 unsigned int r;
107
108 r = VGArCR(index: chan->reg, par: chan->par);
109 r |= PROSAVAGE_I2C_ENAB;
110 if (val) {
111 r |= PROSAVAGE_I2C_SDA_OUT;
112 } else {
113 r &= ~PROSAVAGE_I2C_SDA_OUT;
114 }
115
116 VGAwCR(index: chan->reg, val: r, par: chan->par);
117}
118
119static int prosavage_gpio_getscl(void* data)
120{
121 struct savagefb_i2c_chan *chan = data;
122
123 return (VGArCR(index: chan->reg, par: chan->par) & PROSAVAGE_I2C_SCL_IN) ? 1 : 0;
124}
125
126static int prosavage_gpio_getsda(void* data)
127{
128 struct savagefb_i2c_chan *chan = data;
129
130 return (VGArCR(index: chan->reg, par: chan->par) & PROSAVAGE_I2C_SDA_IN) ? 1 : 0;
131}
132
133static int savage_setup_i2c_bus(struct savagefb_i2c_chan *chan,
134 const char *name)
135{
136 int rc = 0;
137
138 if (chan->par) {
139 strcpy(p: chan->adapter.name, q: name);
140 chan->adapter.owner = THIS_MODULE;
141 chan->adapter.algo_data = &chan->algo;
142 chan->adapter.dev.parent = &chan->par->pcidev->dev;
143 chan->algo.udelay = 10;
144 chan->algo.timeout = 20;
145 chan->algo.data = chan;
146
147 i2c_set_adapdata(adap: &chan->adapter, data: chan);
148
149 /* Raise SCL and SDA */
150 chan->algo.setsda(chan, 1);
151 chan->algo.setscl(chan, 1);
152 udelay(20);
153
154 rc = i2c_bit_add_bus(&chan->adapter);
155
156 if (rc == 0)
157 dev_dbg(&chan->par->pcidev->dev,
158 "I2C bus %s registered.\n", name);
159 else
160 dev_warn(&chan->par->pcidev->dev,
161 "Failed to register I2C bus %s.\n", name);
162 }
163
164 return rc;
165}
166
167void savagefb_create_i2c_busses(struct fb_info *info)
168{
169 struct savagefb_par *par = info->par;
170 par->chan.par = par;
171
172 switch (par->chip) {
173 case S3_PROSAVAGE:
174 case S3_PROSAVAGEDDR:
175 case S3_TWISTER:
176 par->chan.reg = CR_SERIAL2;
177 par->chan.ioaddr = par->mmio.vbase;
178 par->chan.algo.setsda = prosavage_gpio_setsda;
179 par->chan.algo.setscl = prosavage_gpio_setscl;
180 par->chan.algo.getsda = prosavage_gpio_getsda;
181 par->chan.algo.getscl = prosavage_gpio_getscl;
182 break;
183 case S3_SAVAGE4:
184 par->chan.reg = CR_SERIAL1;
185 if (par->pcidev->revision > 1 && !(VGArCR(index: 0xa6, par) & 0x40))
186 par->chan.reg = CR_SERIAL2;
187 par->chan.ioaddr = par->mmio.vbase;
188 par->chan.algo.setsda = prosavage_gpio_setsda;
189 par->chan.algo.setscl = prosavage_gpio_setscl;
190 par->chan.algo.getsda = prosavage_gpio_getsda;
191 par->chan.algo.getscl = prosavage_gpio_getscl;
192 break;
193 case S3_SAVAGE2000:
194 par->chan.reg = MM_SERIAL1;
195 par->chan.ioaddr = par->mmio.vbase;
196 par->chan.algo.setsda = savage4_gpio_setsda;
197 par->chan.algo.setscl = savage4_gpio_setscl;
198 par->chan.algo.getsda = savage4_gpio_getsda;
199 par->chan.algo.getscl = savage4_gpio_getscl;
200 break;
201 default:
202 par->chan.par = NULL;
203 }
204
205 savage_setup_i2c_bus(chan: &par->chan, name: "SAVAGE DDC2");
206}
207
208void savagefb_delete_i2c_busses(struct fb_info *info)
209{
210 struct savagefb_par *par = info->par;
211
212 if (par->chan.par)
213 i2c_del_adapter(adap: &par->chan.adapter);
214
215 par->chan.par = NULL;
216}
217
218int savagefb_probe_i2c_connector(struct fb_info *info, u8 **out_edid)
219{
220 struct savagefb_par *par = info->par;
221 u8 *edid;
222
223 if (par->chan.par)
224 edid = fb_ddc_read(adapter: &par->chan.adapter);
225 else
226 edid = NULL;
227
228 if (!edid) {
229 /* try to get from firmware */
230 const u8 *e = fb_firmware_edid(device: info->device);
231
232 if (e)
233 edid = kmemdup(p: e, EDID_LENGTH, GFP_KERNEL);
234 }
235
236 *out_edid = edid;
237
238 return (edid) ? 0 : 1;
239}
240
241MODULE_LICENSE("GPL");
242

source code of linux/drivers/video/fbdev/savage/savagefb-i2c.c