chromium_ec: Add host command to read board ID

Signed-off-by: Daniel Schaefer <[email protected]>

Author: JohnAZoidberg

framework_lib/src/chromium_ec/command.rs

@@ -105,6 +105,8 @@ pub enum EcCommands {
     GetGpuPcie = 0x3E1E,
     /// Set gpu bay serial and program structure
     ProgramGpuEeprom = 0x3E1F,
+    /// Read board ID of specific ADC channel
+    ReadBoardId = 0x3E26,
 }
 
 pub trait EcRequest<R> {

framework_lib/src/chromium_ec/commands.rs

@@ -1468,3 +1468,22 @@ impl EcRequest<EcResponseSetGpuSerial> for EcRequestSetGpuSerial {
         EcCommands::ProgramGpuEeprom
     }
 }
+
+#[repr(C, packed)]
+pub struct EcRequestReadBoardId {
+    /// ADC Channel, specific to each mainboard schematic
+    pub adc_channel: u8,
+}
+
+#[repr(C, packed)]
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+pub struct EcResponseReadBoardId {
+    /// Board ID (-1 invalid, 15 not present)
+    pub board_id: i8,
+}
+
+impl EcRequest<EcResponseReadBoardId> for EcRequestReadBoardId {
+    fn command_id() -> EcCommands {
+        EcCommands::ReadBoardId
+    }
+}

framework_lib/src/chromium_ec/mod.rs

@@ -1587,6 +1587,22 @@ impl CrosEc {
         }
         Ok(())
     }
+
+    pub fn read_board_id_hc(&self, adc_channel: u8) -> EcResult<Option<u8>> {
+        let res = EcRequestReadBoardId { adc_channel }.send_command(self)?;
+        match res.board_id {
+            -1 => Err(EcError::DeviceError(format!(
+                "Failed to read ADC channel {}",
+                adc_channel
+            ))),
+            15 => Ok(None),
+            0..=14 => Ok(Some(res.board_id as u8)),
+            n => Err(EcError::DeviceError(format!(
+                "Invalid ID to read ADC channel {}",
+                n
+            ))),
+        }
+    }
 }
 
 #[cfg_attr(not(feature = "uefi"), derive(clap::ValueEnum))]