[RFC 4/5] rust: hw: core: Provide some interfaces for the GPIO device

["chenmiao" <chenmiao@openatom.club>]

In irq.rs, we added a new get method for the InterruptSource type to determine
whether an InterruptSource is null. This eliminates the need to repeatedly
call self.cell.get().is_null() for null checks during comparisons.
Additionally, we exposed the slice_as_ptrmethod to support external usage with
the &[InterruptSource]type.

In qdev.rs, we implemented the init_gpio_out_namedfunction, which corresponds
to the C function qdev_init_gpio_out_named. We also refactored the
init_gpio_outfunction to reuse the init_gpio_out_namedinterface.

Signed-off-by: chenmiao <chenmiao@openatom.club>
---
 rust/hw/core/src/irq.rs  |  6 +++++-
 rust/hw/core/src/qdev.rs | 12 +++++++++---
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/rust/hw/core/src/irq.rs b/rust/hw/core/src/irq.rs
index e0d7784..dd5d0ca 100644
--- a/rust/hw/core/src/irq.rs
+++ b/rust/hw/core/src/irq.rs
@@ -71,6 +71,10 @@ pub fn pulse(&self) {
     pub fn raise(&self) {
         self.set(true);
     }
+
+    pub fn get(&self) -> bool {
+        !self.cell.get().is_null()
+    }
 }
 
 impl<T> InterruptSource<T>
@@ -91,7 +95,7 @@ pub(crate) const fn as_ptr(&self) -> *mut *mut bindings::IRQState {
         self.cell.as_ptr()
     }
 
-    pub(crate) const fn slice_as_ptr(slice: &[Self]) -> *mut *mut bindings::IRQState {
+    pub const fn slice_as_ptr(slice: &[Self]) -> *mut *mut bindings::IRQState {
         assert!(!slice.is_empty());
         slice[0].as_ptr()
     }
diff --git a/rust/hw/core/src/qdev.rs b/rust/hw/core/src/qdev.rs
index c3097a2..1d7a0b7 100644
--- a/rust/hw/core/src/qdev.rs
+++ b/rust/hw/core/src/qdev.rs
@@ -17,7 +17,7 @@
 
 pub use crate::bindings::{ClockEvent, DeviceClass, Property, ResetType};
 use crate::{
-    bindings::{self, qdev_init_gpio_in, qdev_init_gpio_out, ResettableClass},
+    bindings::{self, qdev_init_gpio_in, qdev_init_gpio_out_named, ResettableClass},
     irq::InterruptSource,
 };
 
@@ -399,11 +399,17 @@ fn do_init_gpio_in(
     }
 
     fn init_gpio_out(&self, pins: &[InterruptSource]) {
+        self.init_gpio_out_named(pins, "", pins.len());
+    }
+
+    fn init_gpio_out_named(&self, pins: &[InterruptSource], name: &str, n: usize) {
+        let c_name = CString::new(name).expect("gpio name new failed");
         unsafe {
-            qdev_init_gpio_out(
+            qdev_init_gpio_out_named(
                 self.upcast().as_mut_ptr(),
                 InterruptSource::slice_as_ptr(pins),
-                pins.len() as c_int,
+                c_name.as_ptr(),
+                n as c_int,
             );
         }
     }
-- 
2.43.0