1// SPDX-License-Identifier: GPL-2.0
2#include "radeonfb.h"
3
4#include <linux/module.h>
5#include <linux/kernel.h>
6#include <linux/delay.h>
7#include <linux/fb.h>
8
9
10#include <linux/i2c.h>
11#include <linux/i2c-algo-bit.h>
12
13#include <asm/io.h>
14
15#include <video/radeon.h>
16#include "../edid.h"
17
18static void radeon_gpio_setscl(void* data, int state)
19{
20 struct radeon_i2c_chan *chan = data;
21 struct radeonfb_info *rinfo = chan->rinfo;
22 u32 val;
23
24 val = INREG(chan->ddc_reg) & ~(VGA_DDC_CLK_OUT_EN);
25 if (!state)
26 val |= VGA_DDC_CLK_OUT_EN;
27
28 OUTREG(chan->ddc_reg, val);
29 (void)INREG(chan->ddc_reg);
30}
31
32static void radeon_gpio_setsda(void* data, int state)
33{
34 struct radeon_i2c_chan *chan = data;
35 struct radeonfb_info *rinfo = chan->rinfo;
36 u32 val;
37
38 val = INREG(chan->ddc_reg) & ~(VGA_DDC_DATA_OUT_EN);
39 if (!state)
40 val |= VGA_DDC_DATA_OUT_EN;
41
42 OUTREG(chan->ddc_reg, val);
43 (void)INREG(chan->ddc_reg);
44}
45
46static int radeon_gpio_getscl(void* data)
47{
48 struct radeon_i2c_chan *chan = data;
49 struct radeonfb_info *rinfo = chan->rinfo;
50 u32 val;
51
52 val = INREG(chan->ddc_reg);
53
54 return (val & VGA_DDC_CLK_INPUT) ? 1 : 0;
55}
56
57static int radeon_gpio_getsda(void* data)
58{
59 struct radeon_i2c_chan *chan = data;
60 struct radeonfb_info *rinfo = chan->rinfo;
61 u32 val;
62
63 val = INREG(chan->ddc_reg);
64
65 return (val & VGA_DDC_DATA_INPUT) ? 1 : 0;
66}
67
68static int radeon_setup_i2c_bus(struct radeon_i2c_chan *chan, const char *name)
69{
70 int rc;
71
72 snprintf(buf: chan->adapter.name, size: sizeof(chan->adapter.name),
73 fmt: "radeonfb %s", name);
74 chan->adapter.owner = THIS_MODULE;
75 chan->adapter.algo_data = &chan->algo;
76 chan->adapter.dev.parent = &chan->rinfo->pdev->dev;
77 chan->algo.setsda = radeon_gpio_setsda;
78 chan->algo.setscl = radeon_gpio_setscl;
79 chan->algo.getsda = radeon_gpio_getsda;
80 chan->algo.getscl = radeon_gpio_getscl;
81 chan->algo.udelay = 10;
82 chan->algo.timeout = 20;
83 chan->algo.data = chan;
84
85 i2c_set_adapdata(adap: &chan->adapter, data: chan);
86
87 /* Raise SCL and SDA */
88 radeon_gpio_setsda(data: chan, state: 1);
89 radeon_gpio_setscl(data: chan, state: 1);
90 udelay(20);
91
92 rc = i2c_bit_add_bus(&chan->adapter);
93 if (rc == 0)
94 dev_dbg(&chan->rinfo->pdev->dev, "I2C bus %s registered.\n", name);
95 else
96 dev_warn(&chan->rinfo->pdev->dev, "Failed to register I2C bus %s.\n", name);
97 return rc;
98}
99
100void radeon_create_i2c_busses(struct radeonfb_info *rinfo)
101{
102 rinfo->i2c[0].rinfo = rinfo;
103 rinfo->i2c[0].ddc_reg = GPIO_MONID;
104#ifndef CONFIG_PPC
105 rinfo->i2c[0].adapter.class = I2C_CLASS_HWMON;
106#endif
107 radeon_setup_i2c_bus(chan: &rinfo->i2c[0], name: "monid");
108
109 rinfo->i2c[1].rinfo = rinfo;
110 rinfo->i2c[1].ddc_reg = GPIO_DVI_DDC;
111 radeon_setup_i2c_bus(chan: &rinfo->i2c[1], name: "dvi");
112
113 rinfo->i2c[2].rinfo = rinfo;
114 rinfo->i2c[2].ddc_reg = GPIO_VGA_DDC;
115 radeon_setup_i2c_bus(chan: &rinfo->i2c[2], name: "vga");
116
117 rinfo->i2c[3].rinfo = rinfo;
118 rinfo->i2c[3].ddc_reg = GPIO_CRT2_DDC;
119 radeon_setup_i2c_bus(chan: &rinfo->i2c[3], name: "crt2");
120}
121
122void radeon_delete_i2c_busses(struct radeonfb_info *rinfo)
123{
124 if (rinfo->i2c[0].rinfo)
125 i2c_del_adapter(adap: &rinfo->i2c[0].adapter);
126 rinfo->i2c[0].rinfo = NULL;
127
128 if (rinfo->i2c[1].rinfo)
129 i2c_del_adapter(adap: &rinfo->i2c[1].adapter);
130 rinfo->i2c[1].rinfo = NULL;
131
132 if (rinfo->i2c[2].rinfo)
133 i2c_del_adapter(adap: &rinfo->i2c[2].adapter);
134 rinfo->i2c[2].rinfo = NULL;
135
136 if (rinfo->i2c[3].rinfo)
137 i2c_del_adapter(adap: &rinfo->i2c[3].adapter);
138 rinfo->i2c[3].rinfo = NULL;
139}
140
141int radeon_probe_i2c_connector(struct radeonfb_info *rinfo, int conn,
142 u8 **out_edid)
143{
144 u8 *edid;
145
146 edid = fb_ddc_read(adapter: &rinfo->i2c[conn-1].adapter);
147
148 if (out_edid)
149 *out_edid = edid;
150 if (!edid) {
151 pr_debug("radeonfb: I2C (port %d) ... not found\n", conn);
152 return MT_NONE;
153 }
154 if (edid[0x14] & 0x80) {
155 /* Fix detection using BIOS tables */
156 if (rinfo->is_mobility /*&& conn == ddc_dvi*/ &&
157 (INREG(LVDS_GEN_CNTL) & LVDS_ON)) {
158 pr_debug("radeonfb: I2C (port %d) ... found LVDS panel\n", conn);
159 return MT_LCD;
160 } else {
161 pr_debug("radeonfb: I2C (port %d) ... found TMDS panel\n", conn);
162 return MT_DFP;
163 }
164 }
165 pr_debug("radeonfb: I2C (port %d) ... found CRT display\n", conn);
166 return MT_CRT;
167}
168
169

source code of linux/drivers/video/fbdev/aty/radeon_i2c.c