rust: i2c: Reset I2C controller at initialization

Prevent random hangs when restarting the application because
the I2C controller is still in a busy state.
This commit is contained in:
Wladimir J. van der Laan 2020-02-07 13:47:29 +00:00
parent 0fbf997b0d
commit 9e6c9f5a8f

View File

@ -13,6 +13,8 @@ pub trait I2CExt: Deref<Target = i2c0::RegisterBlock> + Sized {
const CLK: sysctl::clock;
#[doc(hidden)]
const DIV: sysctl::threshold;
#[doc(hidden)]
const RESET: sysctl::reset;
/// Constrains I2C peripheral so it plays nicely with the other abstractions
fn constrain(self) -> I2CImpl<Self>;
@ -21,18 +23,21 @@ pub trait I2CExt: Deref<Target = i2c0::RegisterBlock> + Sized {
impl I2CExt for I2C0 {
const CLK: sysctl::clock = sysctl::clock::I2C0;
const DIV: sysctl::threshold = sysctl::threshold::I2C0;
const RESET: sysctl::reset = sysctl::reset::I2C0;
fn constrain(self) -> I2CImpl<Self> { I2CImpl::<Self> { i2c: self } }
}
impl I2CExt for I2C1 {
const CLK: sysctl::clock = sysctl::clock::I2C1;
const DIV: sysctl::threshold = sysctl::threshold::I2C1;
const RESET: sysctl::reset = sysctl::reset::I2C1;
fn constrain(self) -> I2CImpl<Self> { I2CImpl::<Self> { i2c: self } }
}
impl I2CExt for I2C2 {
const CLK: sysctl::clock = sysctl::clock::I2C2;
const DIV: sysctl::threshold = sysctl::threshold::I2C2;
const RESET: sysctl::reset = sysctl::reset::I2C2;
fn constrain(self) -> I2CImpl<Self> { I2CImpl::<Self> { i2c: self } }
}
@ -52,6 +57,7 @@ impl<IF: I2CExt> I2C for I2CImpl<IF> {
// sets up a fixed clock divide by (3+1)*2=8
sysctl::clock_enable(IF::CLK);
sysctl::clock_set_threshold(IF::DIV, 3);
sysctl::reset(IF::RESET);
let v_i2c_freq = sysctl::clock_get_freq(sysctl::clock::I2C0);
let v_period_clk_cnt = v_i2c_freq / i2c_clk / 2;