stm32g473_hal_oppe/fdcan/
id.rs

1//! CAN Identifiers.
2
3use core::cmp::{Ord, Ordering};
4
5use super::message_ram::enums::{IdType, RemoteTransmissionRequest};
6
7/// Standard 11-bit CAN Identifier (`0..=0x7FF`).
8#[derive(Debug, Copy, Clone, Eq, PartialEq)]
9#[cfg_attr(feature = "unstable-defmt", derive(defmt::Format))]
10pub struct StandardId(u16);
11
12impl StandardId {
13    /// CAN ID `0`, the highest priority.
14    pub const ZERO: Self = Self(0);
15
16    /// CAN ID `0x7FF`, the lowest priority.
17    pub const MAX: Self = Self(0x7FF);
18
19    /// Tries to create a `StandardId` from a raw 16-bit integer.
20    ///
21    /// This will return `None` if `raw` is out of range of an 11-bit integer (`> 0x7FF`).
22    #[inline]
23    pub const fn new(raw: u16) -> Option<Self> {
24        if raw <= 0x7FF {
25            Some(Self(raw))
26        } else {
27            None
28        }
29    }
30
31    /// Creates a new `StandardId` without checking if it is inside the valid range.
32    ///
33    /// # Safety
34    ///
35    /// The caller must ensure that `raw` is in the valid range, otherwise the behavior is
36    /// undefined.
37    #[inline]
38    pub const unsafe fn new_unchecked(raw: u16) -> Self {
39        Self(raw)
40    }
41
42    /// Returns this CAN Identifier as a raw 16-bit integer.
43    #[inline]
44    pub fn as_raw(&self) -> u16 {
45        self.0
46    }
47}
48impl From<StandardId> for IdType {
49    fn from(_id: StandardId) -> Self {
50        IdType::StandardId
51    }
52}
53
54/// Extended 29-bit CAN Identifier (`0..=1FFF_FFFF`).
55#[derive(Debug, Copy, Clone, Eq, PartialEq)]
56#[cfg_attr(feature = "unstable-defmt", derive(defmt::Format))]
57pub struct ExtendedId(u32);
58
59impl ExtendedId {
60    /// CAN ID `0`, the highest priority.
61    pub const ZERO: Self = Self(0);
62
63    /// CAN ID `0x1FFFFFFF`, the lowest priority.
64    pub const MAX: Self = Self(0x1FFF_FFFF);
65
66    /// Tries to create a `ExtendedId` from a raw 32-bit integer.
67    ///
68    /// This will return `None` if `raw` is out of range of an 29-bit integer (`> 0x1FFF_FFFF`).
69    #[inline]
70    pub const fn new(raw: u32) -> Option<Self> {
71        if raw <= 0x1FFF_FFFF {
72            Some(Self(raw))
73        } else {
74            None
75        }
76    }
77
78    /// Creates a new `ExtendedId` without checking if it is inside the valid range.
79    ///
80    /// # Safety
81    ///
82    /// The caller must ensure that `raw` is in the valid range, otherwise the behavior is
83    /// undefined.
84    #[inline]
85    pub const unsafe fn new_unchecked(raw: u32) -> Self {
86        Self(raw)
87    }
88
89    /// Returns this CAN Identifier as a raw 32-bit integer.
90    #[inline]
91    pub fn as_raw(&self) -> u32 {
92        self.0
93    }
94
95    /// Returns the Base ID part of this extended identifier.
96    pub fn standard_id(&self) -> StandardId {
97        // ID-28 to ID-18
98        StandardId((self.0 >> 18) as u16)
99    }
100}
101
102impl From<ExtendedId> for IdType {
103    fn from(_id: ExtendedId) -> Self {
104        IdType::ExtendedId
105    }
106}
107
108/// A CAN Identifier (standard or extended).
109#[derive(Debug, Copy, Clone, Eq, PartialEq)]
110#[cfg_attr(feature = "unstable-defmt", derive(defmt::Format))]
111pub enum Id {
112    /// Standard 11-bit Identifier (`0..=0x7FF`).
113    Standard(StandardId),
114
115    /// Extended 29-bit Identifier (`0..=0x1FFF_FFFF`).
116    Extended(ExtendedId),
117}
118
119impl From<StandardId> for Id {
120    #[inline]
121    fn from(id: StandardId) -> Self {
122        Id::Standard(id)
123    }
124}
125
126impl From<ExtendedId> for Id {
127    #[inline]
128    fn from(id: ExtendedId) -> Self {
129        Id::Extended(id)
130    }
131}
132
133impl From<Id> for IdType {
134    #[inline]
135    fn from(id: Id) -> Self {
136        match id {
137            Id::Standard(id) => id.into(),
138            Id::Extended(id) => id.into(),
139        }
140    }
141}
142
143/// Identifier of a CAN message.
144///
145/// FdCan be either a standard identifier (11bit, Range: 0..0x3FF) or a
146/// extendended identifier (29bit , Range: 0..0x1FFFFFFF).
147///
148/// The `Ord` trait can be used to determine the frame’s priority this ID
149/// belongs to.
150/// Lower identifier values have a higher priority. Additionally standard frames
151/// have a higher priority than extended frames and data frames have a higher
152/// priority than remote frames.
153#[derive(Clone, Copy, Debug, PartialEq, Eq)]
154#[cfg_attr(feature = "unstable-defmt", derive(defmt::Format))]
155pub(crate) struct IdReg(u32);
156
157impl IdReg {
158    const STANDARD_SHIFT: u32 = 18;
159    #[allow(dead_code)]
160    const STANDARD_MASK: u32 = 0x1FFC0000;
161
162    const EXTENDED_SHIFT: u32 = 0;
163    const EXTENDED_MASK: u32 = 0x1FFFFFFF;
164
165    const XTD_SHIFT: u32 = 30;
166    const XTD_MASK: u32 = 1 << Self::XTD_SHIFT;
167
168    const RTR_SHIFT: u32 = 29;
169    const RTR_MASK: u32 = 1 << Self::RTR_SHIFT;
170
171    /// Creates a new standard identifier (11bit, Range: 0..0x7FF)
172    ///
173    /// Panics for IDs outside the allowed range.
174    fn new_standard(id: StandardId) -> Self {
175        Self(u32::from(id.as_raw()) << Self::STANDARD_SHIFT)
176    }
177
178    /// Creates a new extendended identifier (29bit , Range: 0..0x1FFFFFFF).
179    ///
180    /// Panics for IDs outside the allowed range.
181    fn new_extended(id: ExtendedId) -> Self {
182        Self(id.as_raw() << Self::EXTENDED_SHIFT | (1 << Self::XTD_SHIFT))
183    }
184
185    pub(crate) fn as_raw_id(&self) -> u32 {
186        self.0 & Self::EXTENDED_MASK
187    }
188
189    pub(crate) fn from_register(id: u32, rtr: RemoteTransmissionRequest, xtd: IdType) -> Self {
190        let rtr: u32 = match rtr {
191            RemoteTransmissionRequest::TransmitDataFrame => 0,
192            RemoteTransmissionRequest::TransmitRemoteFrame => 1 << Self::RTR_SHIFT,
193        };
194        let xtd: u32 = match xtd {
195            IdType::StandardId => 0,
196            IdType::ExtendedId => 1 << Self::XTD_SHIFT,
197        };
198        Self(id | rtr | xtd)
199    }
200
201    /// Sets the remote transmission (RTR) flag. This marks the identifier as
202    /// being part of a remote frame.
203    #[must_use = "returns a new IdReg without modifying `self`"]
204    pub(crate) fn with_rtr(self, rtr: bool) -> Self {
205        if rtr {
206            Self(self.0 | (1 << Self::RTR_SHIFT))
207        } else {
208            Self(self.0 & !Self::RTR_MASK)
209        }
210    }
211
212    /// Returns the identifier.
213    pub fn to_id(self) -> Id {
214        if self.is_extended() {
215            Id::Extended(unsafe {
216                ExtendedId::new_unchecked((self.0 >> Self::EXTENDED_SHIFT) & Self::EXTENDED_MASK)
217            })
218        } else {
219            Id::Standard(unsafe {
220                StandardId::new_unchecked(
221                    ((self.0 >> Self::STANDARD_SHIFT) & Self::STANDARD_MASK) as u16,
222                )
223            })
224        }
225    }
226
227    /// Returns `true` if the identifier is an extended identifier.
228    pub fn is_extended(self) -> bool {
229        (self.0 & Self::XTD_MASK) != 0
230    }
231
232    /// Returns `true` if the identifier is a standard identifier.
233    pub fn is_standard(self) -> bool {
234        !self.is_extended()
235    }
236
237    /// Returns `true` if the identifer is part of a remote frame (RTR bit set).
238    pub(crate) fn rtr(self) -> bool {
239        self.0 & Self::RTR_MASK != 0
240    }
241}
242impl From<Id> for IdReg {
243    fn from(id: Id) -> Self {
244        match id {
245            Id::Standard(s) => IdReg::new_standard(s),
246            Id::Extended(e) => IdReg::new_extended(e),
247        }
248    }
249}
250impl From<IdReg> for Id {
251    fn from(idr: IdReg) -> Self {
252        idr.to_id()
253    }
254}
255impl From<IdReg> for IdType {
256    #[inline]
257    fn from(id: IdReg) -> Self {
258        if id.is_standard() {
259            IdType::StandardId
260        } else {
261            IdType::ExtendedId
262        }
263    }
264}
265impl From<IdReg> for RemoteTransmissionRequest {
266    #[inline]
267    fn from(id: IdReg) -> Self {
268        if id.rtr() {
269            RemoteTransmissionRequest::TransmitRemoteFrame
270        } else {
271            RemoteTransmissionRequest::TransmitDataFrame
272        }
273    }
274}
275
276/// `IdReg` is ordered by priority.
277impl Ord for IdReg {
278    fn cmp(&self, other: &Self) -> Ordering {
279        // When the IDs match, data frames have priority over remote frames.
280        let rtr = self.rtr().cmp(&other.rtr()).reverse();
281
282        let id_a = self.to_id();
283        let id_b = other.to_id();
284        match (id_a, id_b) {
285            (Id::Standard(a), Id::Standard(b)) => {
286                // Lower IDs have priority over higher IDs.
287                a.as_raw().cmp(&b.as_raw()).reverse().then(rtr)
288            }
289            (Id::Extended(a), Id::Extended(b)) => a.as_raw().cmp(&b.as_raw()).reverse().then(rtr),
290            (Id::Standard(a), Id::Extended(b)) => {
291                // Standard frames have priority over extended frames if their Base IDs match.
292                a.as_raw()
293                    .cmp(&b.standard_id().as_raw())
294                    .reverse()
295                    .then(Ordering::Greater)
296            }
297            (Id::Extended(a), Id::Standard(b)) => a
298                .standard_id()
299                .as_raw()
300                .cmp(&b.as_raw())
301                .reverse()
302                .then(Ordering::Less),
303        }
304    }
305}
306
307impl PartialOrd for IdReg {
308    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
309        Some(self.cmp(other))
310    }
311}
stm32g473_hal_oppe/fdcan/id.rs

stm32g473_hal_oppe/fdcan/
id.rs
