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
|
// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2019 Rockchip Electronics Co., Ltd
*/
#include <linux/stddef.h>
#include <adc.h>
#include <asm/io.h>
#include <dm.h>
#include <env.h>
#include <stdlib.h>
#define DTB_DIR "rockchip/"
struct oga_model {
const u16 adc_value;
const char *board;
const char *board_name;
const char *fdtfile;
};
enum oga_device_id {
OGA,
OGA_V11,
OGS,
};
/*
* All ADC values from schematic of Odroid Go Advance Black Edition.
* Value for OGS is inferred based on schematic and observed values.
*/
static const struct oga_model oga_model_details[] = {
[OGA] = {
856,
"rk3326-odroid-go2",
"ODROID-GO Advance",
DTB_DIR "rk3326-odroid-go2.dtb",
},
[OGA_V11] = {
677,
"rk3326-odroid-go2-v11",
"ODROID-GO Advance Black Edition",
DTB_DIR "rk3326-odroid-go2-v11.dtb",
},
[OGS] = {
85,
"rk3326-odroid-go3",
"ODROID-GO Super",
DTB_DIR "rk3326-odroid-go3.dtb",
},
};
/* Detect which Odroid Go Advance device we are using so as to load the
* correct devicetree for Linux. Set an environment variable once
* found. The detection depends on the value of ADC channel 0.
*/
int oga_detect_device(void)
{
u32 adc_info;
int ret, i;
int board_id = -ENXIO;
ret = adc_channel_single_shot("saradc@ff288000", 0, &adc_info);
if (ret) {
printf("Read SARADC failed with error %d\n", ret);
return ret;
}
/*
* Get the correct device from the table. The ADC value is
* determined by a resistor on ADC channel 0. The manufacturer
* accounted for this with a 5% tolerance, so assume a +- value
* of 50 should be enough.
*/
for (i = 0; i < ARRAY_SIZE(oga_model_details); i++) {
u32 adc_min = oga_model_details[i].adc_value - 50;
u32 adc_max = oga_model_details[i].adc_value + 50;
if (adc_min < adc_info && adc_max > adc_info) {
board_id = i;
break;
}
}
if (board_id < 0)
return board_id;
env_set("board", oga_model_details[board_id].board);
env_set("board_name",
oga_model_details[board_id].board_name);
env_set("fdtfile", oga_model_details[board_id].fdtfile);
return 0;
}
int rk_board_late_init(void)
{
int ret;
ret = oga_detect_device();
if (ret) {
printf("Unable to detect device type: %d\n", ret);
return ret;
}
return 0;
}
|