hardware 0.0.9

A no_std bare-metal hardware abstraction layer — all port I/O, memory and swap allocations are guarded at runtime. Do not consider this dependency stable before x.1.x
Documentation 
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

#[derive(Copy, Clone, PartialEq)]
pub enum SensorKind {
    Accelerometer,
    Gyroscope,
    Magnetometer,
    Barometer,
    Proximity,
    Light,
    Imu,
    Temperature,
    Humidity,
    Gravity,
    Unknown,
}

#[derive(Copy, Clone)]
pub struct SensorDevice {
    pub kind: SensorKind,
    pub reg_base: u64,
    pub irq: u32,
    pub compat: [u8; 64],
    pub compat_len: usize,
}

pub fn detect(out: &mut [SensorDevice]) -> usize {
    if out.is_empty() {
        return 0;
    }
    scan_dt(out)
}

fn scan_dt(out: &mut [SensorDevice]) -> usize {
    let mut blob = [0u8; 4096];
    let blen = crate::firmware::devicetree::load_fdt_blob(&mut blob);
    if blen < 40 {
        return 0;
    }
    let mut entries = [crate::firmware::devicetree::DtDeviceEntry {
        name: [0u8; 64],
        name_len: 0,
        reg_base: 0,
        reg_size: 0,
        irq: 0,
        compatible: [0u8; 128],
        compatible_len: 0,
    }; 64];
    let count = crate::firmware::devicetree::enumerate_devices(&blob[..blen], &mut entries);
    let mut found = 0usize;
    let mut i = 0usize;
    while i < count && found < out.len() {
        let compat = &entries[i].compatible[..entries[i].compatible_len];
        let kind = classify_sensor(compat, &entries[i].name[..entries[i].name_len]);
        if !matches!(kind, SensorKind::Unknown) {
            let mut compat_buf = [0u8; 64];
            let clen = copy_min(compat, &mut compat_buf);
            out[found] = SensorDevice {
                kind,
                reg_base: entries[i].reg_base,
                irq: entries[i].irq,
                compat: compat_buf,
                compat_len: clen,
            };
            found += 1;
        }
        i += 1;
    }
    found
}

fn classify_sensor(compat: &[u8], name: &[u8]) -> SensorKind {
    if contains(compat, b"mpu6050")
        || contains(compat, b"mpu6500")
        || contains(compat, b"mpu9250")
        || contains(compat, b"icm20")
        || contains(compat, b"bmi160")
        || contains(compat, b"bmi270")
        || contains(compat, b"lsm6ds")
        || contains(name, b"imu")
    {
        return SensorKind::Imu;
    }
    if contains(compat, b"bma")
        || contains(compat, b"lis3dh")
        || contains(compat, b"lis2dh")
        || contains(compat, b"kxtj")
        || contains(compat, b"adxl")
        || contains(compat, b"mc3")
        || contains(name, b"accel")
    {
        return SensorKind::Accelerometer;
    }
    if contains(compat, b"l3g") || contains(compat, b"bmg") || contains(name, b"gyro") {
        return SensorKind::Gyroscope;
    }
    if contains(compat, b"ak8963")
        || contains(compat, b"ak09911")
        || contains(compat, b"mmc5603")
        || contains(compat, b"hmc5883")
        || contains(compat, b"bmm150")
        || contains(name, b"magn")
    {
        return SensorKind::Magnetometer;
    }
    if contains(compat, b"bmp")
        || contains(compat, b"ms5611")
        || contains(compat, b"lps22")
        || contains(compat, b"hp206c")
        || contains(name, b"baro")
    {
        return SensorKind::Barometer;
    }
    if contains(compat, b"stk3")
        || contains(compat, b"apds9")
        || contains(compat, b"vcnl4")
        || contains(name, b"prox")
    {
        return SensorKind::Proximity;
    }
    if contains(compat, b"tsl2")
        || contains(compat, b"bh1750")
        || contains(compat, b"veml")
        || contains(compat, b"ltr5")
        || contains(name, b"light")
        || contains(name, b"als")
    {
        return SensorKind::Light;
    }
    if contains(compat, b"tmp1")
        || contains(compat, b"lm75")
        || contains(compat, b"aht")
        || contains(name, b"temp")
    {
        return SensorKind::Temperature;
    }
    if contains(compat, b"hdc1")
        || contains(compat, b"sht")
        || contains(compat, b"si7021")
        || contains(name, b"humid")
    {
        return SensorKind::Humidity;
    }
    SensorKind::Unknown
}

fn copy_min(src: &[u8], dst: &mut [u8; 64]) -> usize {
    let n = if src.len() < 64 { src.len() } else { 64 };
    let mut i = 0usize;
    while i < n {
        dst[i] = src[i];
        i += 1;
    }
    n
}

fn contains(haystack: &[u8], needle: &[u8]) -> bool {
    if needle.len() > haystack.len() {
        return false;
    }
    let mut i = 0usize;
    while i + needle.len() <= haystack.len() {
        let mut ok = true;
        let mut j = 0usize;
        while j < needle.len() {
            if haystack[i + j] != needle[j] {
                ok = false;
                break;
            }
            j += 1;
        }
        if ok {
            return true;
        }
        i += 1;
    }
    false
}