artiq/artiq/firmware/libboard_misoc/i2c_eeprom.rs

67 lines
1.8 KiB
Rust

use i2c;
/// [Hardware manual](http://ww1.microchip.com/downloads/en/DeviceDoc/24AA02E48-24AA025E48-24AA02E64-24AA025E64-Data-Sheet-20002124H.pdf)
pub struct EEPROM {
busno: u8,
port: u8,
address: u8,
}
impl EEPROM {
#[cfg(all(soc_platform = "kasli", any(hw_rev = "v1.0", hw_rev = "v1.1")))]
pub fn new() -> Self {
EEPROM {
busno: 0,
/// Same port as Si5324
port: 11,
address: 0xa0,
}
}
#[cfg(all(soc_platform = "kasli", hw_rev = "v2.0"))]
pub fn new() -> Self {
EEPROM {
busno: 0,
/// SHARED I2C bus
port: 11,
address: 0xae,
}
}
#[cfg(soc_platform = "kasli")]
fn select(&self) -> Result<(), &'static str> {
let mask: u16 = 1 << self.port;
i2c::switch_select(self.busno, 0x70, mask as u8)?;
i2c::switch_select(self.busno, 0x71, (mask >> 8) as u8)?;
Ok(())
}
pub fn read<'a>(&self, addr: u8, buf: &'a mut [u8]) -> Result<(), &'static str> {
self.select()?;
i2c::start(self.busno)?;
i2c::write(self.busno, self.address)?;
i2c::write(self.busno, addr)?;
i2c::restart(self.busno)?;
i2c::write(self.busno, self.address | 1)?;
let buf_len = buf.len();
for (i, byte) in buf.iter_mut().enumerate() {
*byte = i2c::read(self.busno, i < buf_len - 1)?;
}
i2c::stop(self.busno)?;
Ok(())
}
/// > The 24AA02XEXX is programmed at the factory with a
/// > globally unique node address stored in the upper half
/// > of the array and permanently write-protected.
pub fn read_eui48<'a>(&self) -> Result<[u8; 6], &'static str> {
let mut buffer = [0u8; 6];
self.read(0xFA, &mut buffer)?;
Ok(buffer)
}
}