embassy_net_wiznet/
device.rs

1use core::marker::PhantomData;
2
3use embedded_hal_async::spi::SpiDevice;
4
5use crate::chip::Chip;
6
7#[repr(u8)]
8enum Command {
9    Open = 0x01,
10    Send = 0x20,
11    Receive = 0x40,
12}
13
14#[repr(u8)]
15enum Interrupt {
16    Receive = 0b00100_u8,
17}
18
19/// Wiznet chip in MACRAW mode
20#[derive(Debug)]
21#[cfg_attr(feature = "defmt", derive(defmt::Format))]
22pub(crate) struct WiznetDevice<C, SPI> {
23    spi: SPI,
24    _phantom: PhantomData<C>,
25}
26
27/// Error type when initializing a new Wiznet device
28pub enum InitError<SE> {
29    /// Error occurred when sending or receiving SPI data
30    SpiError(SE),
31    /// The chip returned a version that isn't expected or supported
32    InvalidChipVersion {
33        /// The version that is supported
34        expected: u8,
35        /// The version that was returned by the chip
36        actual: u8,
37    },
38}
39
40impl<SE> From<SE> for InitError<SE> {
41    fn from(e: SE) -> Self {
42        InitError::SpiError(e)
43    }
44}
45
46impl<SE> core::fmt::Debug for InitError<SE>
47where
48    SE: core::fmt::Debug,
49{
50    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
51        match self {
52            InitError::SpiError(e) => write!(f, "SpiError({:?})", e),
53            InitError::InvalidChipVersion { expected, actual } => {
54                write!(f, "InvalidChipVersion {{ expected: {}, actual: {} }}", expected, actual)
55            }
56        }
57    }
58}
59
60#[cfg(feature = "defmt")]
61impl<SE> defmt::Format for InitError<SE>
62where
63    SE: defmt::Format,
64{
65    fn format(&self, f: defmt::Formatter) {
66        match self {
67            InitError::SpiError(e) => defmt::write!(f, "SpiError({})", e),
68            InitError::InvalidChipVersion { expected, actual } => {
69                defmt::write!(f, "InvalidChipVersion {{ expected: {}, actual: {} }}", expected, actual)
70            }
71        }
72    }
73}
74
75impl<C: Chip, SPI: SpiDevice> WiznetDevice<C, SPI> {
76    /// Create and initialize the driver
77    pub async fn new(spi: SPI, mac_addr: [u8; 6]) -> Result<Self, InitError<SPI::Error>> {
78        let mut this = Self {
79            spi,
80            _phantom: PhantomData,
81        };
82
83        // Reset device
84        this.bus_write(C::COMMON_MODE, &[0x80]).await?;
85
86        // Check the version of the chip
87        let mut version = [0];
88        this.bus_read(C::COMMON_VERSION, &mut version).await?;
89        if version[0] != C::CHIP_VERSION {
90            #[cfg(feature = "defmt")]
91            defmt::error!("invalid chip version: {} (expected {})", version[0], C::CHIP_VERSION);
92            return Err(InitError::InvalidChipVersion {
93                actual: version[0],
94                expected: C::CHIP_VERSION,
95            });
96        }
97
98        // Enable interrupt pin
99        this.bus_write(C::COMMON_SOCKET_INTR, &[0x01]).await?;
100        // Enable receive interrupt
101        this.bus_write(C::SOCKET_INTR_MASK, &[Interrupt::Receive as u8]).await?;
102
103        // Set MAC address
104        this.bus_write(C::COMMON_MAC, &mac_addr).await?;
105
106        // Set the raw socket RX/TX buffer sizes.
107        let buf_kbs = (C::BUF_SIZE / 1024) as u8;
108        this.bus_write(C::SOCKET_TXBUF_SIZE, &[buf_kbs]).await?;
109        this.bus_write(C::SOCKET_RXBUF_SIZE, &[buf_kbs]).await?;
110
111        // MACRAW mode with MAC filtering.
112        this.bus_write(C::SOCKET_MODE, &[C::SOCKET_MODE_VALUE]).await?;
113        this.command(Command::Open).await?;
114
115        Ok(this)
116    }
117
118    async fn bus_read(&mut self, address: C::Address, data: &mut [u8]) -> Result<(), SPI::Error> {
119        C::bus_read(&mut self.spi, address, data).await
120    }
121
122    async fn bus_write(&mut self, address: C::Address, data: &[u8]) -> Result<(), SPI::Error> {
123        C::bus_write(&mut self.spi, address, data).await
124    }
125
126    async fn reset_interrupt(&mut self, code: Interrupt) -> Result<(), SPI::Error> {
127        let data = [code as u8];
128        self.bus_write(C::SOCKET_INTR, &data).await
129    }
130
131    async fn get_tx_write_ptr(&mut self) -> Result<u16, SPI::Error> {
132        let mut data = [0u8; 2];
133        self.bus_read(C::SOCKET_TX_DATA_WRITE_PTR, &mut data).await?;
134        Ok(u16::from_be_bytes(data))
135    }
136
137    async fn set_tx_write_ptr(&mut self, ptr: u16) -> Result<(), SPI::Error> {
138        let data = ptr.to_be_bytes();
139        self.bus_write(C::SOCKET_TX_DATA_WRITE_PTR, &data).await
140    }
141
142    async fn get_rx_read_ptr(&mut self) -> Result<u16, SPI::Error> {
143        let mut data = [0u8; 2];
144        self.bus_read(C::SOCKET_RX_DATA_READ_PTR, &mut data).await?;
145        Ok(u16::from_be_bytes(data))
146    }
147
148    async fn set_rx_read_ptr(&mut self, ptr: u16) -> Result<(), SPI::Error> {
149        let data = ptr.to_be_bytes();
150        self.bus_write(C::SOCKET_RX_DATA_READ_PTR, &data).await
151    }
152
153    async fn command(&mut self, command: Command) -> Result<(), SPI::Error> {
154        let data = [command as u8];
155        self.bus_write(C::SOCKET_COMMAND, &data).await
156    }
157
158    async fn get_rx_size(&mut self) -> Result<u16, SPI::Error> {
159        loop {
160            // Wait until two sequential reads are equal
161            let mut res0 = [0u8; 2];
162            self.bus_read(C::SOCKET_RECVD_SIZE, &mut res0).await?;
163            let mut res1 = [0u8; 2];
164            self.bus_read(C::SOCKET_RECVD_SIZE, &mut res1).await?;
165            if res0 == res1 {
166                break Ok(u16::from_be_bytes(res0));
167            }
168        }
169    }
170
171    async fn get_tx_free_size(&mut self) -> Result<u16, SPI::Error> {
172        let mut data = [0; 2];
173        self.bus_read(C::SOCKET_TX_FREE_SIZE, &mut data).await?;
174        Ok(u16::from_be_bytes(data))
175    }
176
177    /// Read bytes from the RX buffer.
178    async fn read_bytes(&mut self, read_ptr: &mut u16, buffer: &mut [u8]) -> Result<(), SPI::Error> {
179        if C::AUTO_WRAP {
180            self.bus_read(C::rx_addr(*read_ptr), buffer).await?;
181        } else {
182            let addr = *read_ptr % C::BUF_SIZE;
183            if addr as usize + buffer.len() <= C::BUF_SIZE as usize {
184                self.bus_read(C::rx_addr(addr), buffer).await?;
185            } else {
186                let n = C::BUF_SIZE - addr;
187                self.bus_read(C::rx_addr(addr), &mut buffer[..n as usize]).await?;
188                self.bus_read(C::rx_addr(0), &mut buffer[n as usize..]).await?;
189            }
190        }
191
192        *read_ptr = (*read_ptr).wrapping_add(buffer.len() as u16);
193
194        Ok(())
195    }
196
197    /// Read an ethernet frame from the device. Returns the number of bytes read.
198    pub async fn read_frame(&mut self, frame: &mut [u8]) -> Result<usize, SPI::Error> {
199        let rx_size = self.get_rx_size().await? as usize;
200        if rx_size == 0 {
201            return Ok(0);
202        }
203
204        self.reset_interrupt(Interrupt::Receive).await?;
205
206        let mut read_ptr = self.get_rx_read_ptr().await?;
207
208        // First two bytes gives the size of the received ethernet frame
209        let expected_frame_size: usize = {
210            let mut frame_bytes = [0u8; 2];
211            self.read_bytes(&mut read_ptr, &mut frame_bytes).await?;
212            u16::from_be_bytes(frame_bytes) as usize - 2
213        };
214
215        // Read the ethernet frame
216        self.read_bytes(&mut read_ptr, &mut frame[..expected_frame_size])
217            .await?;
218
219        // Register RX as completed
220        self.set_rx_read_ptr(read_ptr).await?;
221        self.command(Command::Receive).await?;
222
223        Ok(expected_frame_size)
224    }
225
226    /// Write an ethernet frame to the device. Returns number of bytes written
227    pub async fn write_frame(&mut self, frame: &[u8]) -> Result<usize, SPI::Error> {
228        while self.get_tx_free_size().await? < frame.len() as u16 {}
229        let write_ptr = self.get_tx_write_ptr().await?;
230
231        if C::AUTO_WRAP {
232            self.bus_write(C::tx_addr(write_ptr), frame).await?;
233        } else {
234            let addr = write_ptr % C::BUF_SIZE;
235            if addr as usize + frame.len() <= C::BUF_SIZE as usize {
236                self.bus_write(C::tx_addr(addr), frame).await?;
237            } else {
238                let n = C::BUF_SIZE - addr;
239                self.bus_write(C::tx_addr(addr), &frame[..n as usize]).await?;
240                self.bus_write(C::tx_addr(0), &frame[n as usize..]).await?;
241            }
242        }
243
244        self.set_tx_write_ptr(write_ptr.wrapping_add(frame.len() as u16))
245            .await?;
246        self.command(Command::Send).await?;
247        Ok(frame.len())
248    }
249
250    pub async fn is_link_up(&mut self) -> bool {
251        let mut link = [0];
252        self.bus_read(C::COMMON_PHY_CFG, &mut link).await.ok();
253        link[0] & 1 == 1
254    }
255}