ccs: pl: properly parse errors

Cargo.lock

@@ -255,6 +255,7 @@ dependencies = [
  "rocket",
  "serde",
  "serde_json",
+ "thiserror 2.0.11",
  "tokio",
  "tokio-modbus",
  "tokio-serial",
@@ -1592,7 +1593,7 @@ dependencies = [
  "rustc-hash",
  "rustls",
  "socket2",
- "thiserror 2.0.9",
+ "thiserror 2.0.11",
  "tokio",
  "tracing",
 ]
@@ -1611,7 +1612,7 @@ dependencies = [
  "rustls",
  "rustls-pki-types",
  "slab",
- "thiserror 2.0.9",
+ "thiserror 2.0.11",
  "tinyvec",
  "tracing",
  "web-time",
@@ -2223,7 +2224,7 @@ dependencies = [
  "serde",
  "serde_json",
  "serialport",
- "thiserror 2.0.9",
+ "thiserror 2.0.11",
  "tokio",
  "tokio-modbus",
  "tokio-serial",
@@ -2240,11 +2241,11 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "2.0.9"
+version = "2.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f072643fd0190df67a8bab670c20ef5d8737177d6ac6b2e9a236cb096206b2cc"
+checksum = "d452f284b73e6d76dd36758a0c8684b1d5be31f92b89d07fd5822175732206fc"
 dependencies = [
- "thiserror-impl 2.0.9",
+ "thiserror-impl 2.0.11",
 ]
 
 [[package]]
@@ -2260,9 +2261,9 @@ dependencies = [
 
 [[package]]
 name = "thiserror-impl"
-version = "2.0.9"
+version = "2.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7b50fa271071aae2e6ee85f842e2e28ba8cd2c5fb67f11fcb1fd70b276f9e7d4"
+checksum = "26afc1baea8a989337eeb52b6e72a039780ce45c3edfcc9c5b9d112feeb173c2"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2377,7 +2378,7 @@ dependencies = [
  "futures-util",
  "log",
  "smallvec",
- "thiserror 2.0.9",
+ "thiserror 2.0.11",
  "tokio",
  "tokio-util",
 ]

charge-controller-supervisor/Cargo.toml

@@ -26,6 +26,7 @@ prometheus = "0.13.4"
 rocket = { version = "0.5.1", features = ["json"] }
 serde = { version = "1.0.216", features = ["derive"] }
 serde_json = "1.0.134"
+thiserror = "2.0.11"
 tokio = { version = "1.42.0", features = ["full"] }
 tokio-modbus = "0.16.1"
 tokio-serial = "5.4.4"

charge-controller-supervisor/src/controller/pl.rs

@@ -298,11 +298,10 @@ impl Pli {
         T: Into<u8>,
     {
         self.send_command(command(20, address.into(), 0)).await?;
-        let buf = self.receive::<1>().await?;
-        if buf[0] == 200 {
-            Ok(self.receive::<1>().await?[0])
-        } else {
-            Err(eyre::eyre!("read error: result is {}", buf[0]))
+        let response = self.get_response().await?;
+        match response {
+            Ok(()) => Ok(self.receive::<1>().await?[0]),
+            Err(e) => Err(e.into()),
         }
     }
 
@@ -320,11 +319,61 @@ impl Pli {
         T: Into<u8>,
     {
         self.send_command(command(72, address.into(), 0)).await?;
-        let buf = self.receive::<1>().await?;
-        if buf[0] == 200 {
-            Ok(self.receive::<1>().await?[0])
-        } else {
-            Err(eyre::eyre!("read error: result is {}", buf[0]))
+
+        let response = self.get_response().await?;
+        match response {
+            Ok(()) => Ok(self.receive::<1>().await?[0]),
+            Err(e) => Err(e.into()),
+        }
+    }
+
+    async fn get_response(&mut self) -> eyre::Result<Result<(), PlError>> {
+        let res = self.receive::<1>().await?[0];
+        Ok(PlError::parse(res))
+    }
+}
+
+#[derive(thiserror::Error, Debug)]
+enum PlError {
+    #[error("No comms or corrupt comms")]
+    NoComms,
+    #[error("Loopback response code")]
+    Loopback,
+    #[error("Timeout error")]
+    Timeout,
+    #[error("Checksum error in PLI receive data.")]
+    Checksum,
+    #[error("Command received by PLI is not recognised.")]
+    CommandNotRecognised,
+    #[error("Unused - or could be returning PL40 version!")]
+    Unused1,
+    #[error("Processor did not receive a reply to request.")]
+    NoReply,
+    #[error("Error in reply from PL.")]
+    ErrorFromPl,
+    #[error("<not used> #2")]
+    Unused2,
+    #[error("<not used> #3")]
+    Unused3,
+    #[error("Unknown: {0:#X?}")]
+    Unknown(u8),
+}
+
+impl PlError {
+    const fn parse(value: u8) -> Result<(), Self> {
+        match value {
+            200 => Ok(()),
+            5 => Err(Self::NoComms),
+            128 => Err(Self::Loopback),
+            129 => Err(Self::Timeout),
+            130 => Err(Self::Checksum),
+            131 => Err(Self::CommandNotRecognised),
+            132 => Err(Self::Unused1),
+            133 => Err(Self::NoReply),
+            134 => Err(Self::ErrorFromPl),
+            135 => Err(Self::Unused2),
+            136 => Err(Self::Unused3),
+            v => Err(Self::Unknown(v)),
         }
     }
 }