Make legacy_interrupt_line an Option

Drivers don't need to know the exact legacy_interrupt_pin in use.
Just if legacy interrupts are enabled and if so which
legacy_interrupt_line is used.

pcid/src/driver_interface/mod.rs

@@ -57,10 +57,8 @@ pub struct PciFunction {
     /// Legacy IRQ line: It's the responsibility of pcid to make sure that it be mapped in either
     /// the I/O APIC or the 8259 PIC, so that the subdriver can map the interrupt vector directly.
     /// The vector to map is always this field, plus 32.
-    pub legacy_interrupt_line: u8,
-
-    /// Legacy interrupt pin (INTx#), none if INTx# interrupts aren't supported at all.
-    pub legacy_interrupt_pin: Option<LegacyInterruptPin>,
+    /// If INTx# interrupts aren't supported at all this is `None`.
+    pub legacy_interrupt_line: Option<u8>,
 
     /// All identifying information of the PCI function.
     pub full_device_id: FullDeviceId,

pcid/src/main.rs

@@ -280,6 +280,16 @@ fn handle_parsed_header(state: Arc<State>, config: &Config, addr: PciAddress, he
             state.pcie.write(addr, 0x3C, data);
         };
 
+        let legacy_interrupt_enabled = match interrupt_pin {
+            0 => false,
+            1 | 2 | 3 | 4 => true,
+
+            other => {
+                warn!("pcid: invalid interrupt pin: {}", other);
+                false
+            }
+        };
+
         let capabilities = if endpoint_header.status(&state.pcie).has_capability_list() {
             let func = PciFunc {
                 pci: &state.pcie,
@@ -291,26 +301,10 @@ fn handle_parsed_header(state: Arc<State>, config: &Config, addr: PciAddress, he
         };
         debug!("PCI DEVICE CAPABILITIES for {}: {:?}", args.iter().map(|string| string.as_ref()).nth(0).unwrap_or("[unknown]"), capabilities);
 
-        use driver_interface::LegacyInterruptPin;
-
-        let legacy_interrupt_pin = match interrupt_pin {
-            0 => None,
-            1 => Some(LegacyInterruptPin::IntA),
-            2 => Some(LegacyInterruptPin::IntB),
-            3 => Some(LegacyInterruptPin::IntC),
-            4 => Some(LegacyInterruptPin::IntD),
-
-            other => {
-                warn!("pcid: invalid interrupt pin: {}", other);
-                None
-            }
-        };
-
         let func = driver_interface::PciFunction {
             bars,
             addr,
-            legacy_interrupt_line: irq,
-            legacy_interrupt_pin,
+            legacy_interrupt_line: if legacy_interrupt_enabled { Some(irq) } else { None },
             full_device_id: header.full_device_id().clone(),
         };