i2c: add max_retry to i2c read and fix i2c-demo (#14)

Signed-off-by: Junxing Zhu <zjx1319@hust.edu.cn>
rustsbi · Dec 24, 2024 · c167e09 · c167e09
1 parent 69b39c5
commit c167e09
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Showing 2 changed files with 16 additions and 6 deletions.
diff --git a/bouffalo-hal/src/i2c.rs b/bouffalo-hal/src/i2c.rs
@@ -631,9 +631,15 @@ impl<I2C: Deref<Target = RegisterBlock>, PADS> embedded_hal::i2c::I2c for I2c<I2
                     };
 
                     let mut i = 0;
+                    let max_retry = len * 100;
+                    let mut retry = 0;
                     while i < len {
                         while self.i2c.fifo_config_1.read().receive_available_bytes() == 0 {
-                            core::hint::spin_loop();
+                            retry += 1;
+                            if retry >= max_retry {
+                                unsafe { self.i2c.config.modify(|config| config.disable_master()) };
+                                return Err(Error::Other);
+                            }
                         }
                         let word = self.i2c.fifo_read.read();
                         let bytes_to_read = core::cmp::min(len - i, 4);

diff --git a/examples/peripherals/i2c-demo/src/main.rs b/examples/peripherals/i2c-demo/src/main.rs
@@ -21,12 +21,18 @@ fn main(p: Peripherals, c: Clocks) -> ! {
     let mut serial = p.uart0.freerun(config, pads, &c).unwrap();
     let mut led = p.gpio.io8.into_floating_output();
 
-    let scl = p.gpio.io6.into_i2c::<2>();
-    let sda = p.gpio.io7.into_i2c::<2>();
+    let scl = p.gpio.io6.into_i2c::<0>();
+    let sda = p.gpio.io7.into_i2c::<0>();
     let mut i2c = I2c::new(p.i2c0, (scl, sda), &p.glb);
     i2c.enable_sub_address(SCREEN_TOUCH_SUB_ADDRESS);
 
     writeln!(serial, "Hello Rust🦀!").ok();
+    writeln!(
+        serial,
+        "Welcome to I2C demo, touch the screen to turn on the LED"
+    )
+    .ok();
+    led.set_high().ok();
     let mut buf = [0u8; 6];
     loop {
         riscv::asm::delay(100_000);
@@ -39,9 +45,7 @@ fn main(p: Peripherals, c: Clocks) -> ! {
                 }
                 writeln!(serial, "pos: ({}, {})[{}]", buf[3], buf[5], buf[2] >> 4).ok();
             }
-            Err(_) => {
-                led.set_high().ok();
-            }
+            Err(_) => {}
         }
     }
 }