diff --git a/src/platform/nvme_ioctl.rs b/src/platform/nvme_ioctl.rs
index 8773fdd..1876e9b 100644
--- a/src/platform/nvme_ioctl.rs
+++ b/src/platform/nvme_ioctl.rs
@@ -7,18 +7,6 @@ use std::fs::OpenOptions;
 use std::os::unix::io::AsRawFd;
 use std::path::Path;
 
-// NVME_IOCTL_ADMIN_CMD = 0xC0484E41
-const NVME_IOCTL_ADMIN_CMD: libc::c_ulong = 0xC0484E41;
-
-// NVMe admin command opcode for Get Log Page
-const NVME_ADMIN_GET_LOG_PAGE: u8 = 0x02;
-
-// SMART/Health log page identifier
-const NVME_LOG_SMART: u32 = 0x02;
-
-// Size of the SMART log in bytes
-const SMART_LOG_SIZE: u32 = 512;
-
 /// NVMe Admin Command structure passed to the ioctl.
 #[repr(C)]
 #[derive(Default)]
@@ -69,6 +57,17 @@ pub struct NvmeSmartLog {
     pub rsvd_tail: [u8; 296],
 }
 
+const NVME_IOCTL_ADMIN_CMD: libc::Ioctl = libc::_IOWR::<NvmeAdminCmd>(b'N' as u32, 0x41);
+
+// NVMe admin command opcode for Get Log Page
+const NVME_ADMIN_GET_LOG_PAGE: u8 = 0x02;
+
+// SMART/Health log page identifier
+const NVME_LOG_SMART: u32 = 0x02;
+
+// Size of the SMART log in bytes
+const SMART_LOG_SIZE: u32 = 512;
+
 /// Read the NVMe SMART/Health log from a controller device (e.g. `/dev/nvme0`).
 ///
 /// Returns `None` if the device cannot be opened or the ioctl fails.
diff --git a/src/platform/sata_ioctl.rs b/src/platform/sata_ioctl.rs
index 5482306..f20b012 100644
--- a/src/platform/sata_ioctl.rs
+++ b/src/platform/sata_ioctl.rs
@@ -9,7 +9,7 @@ use std::os::unix::io::AsRawFd;
 use std::path::Path;
 
 // SG_IO ioctl request number
-const SG_IO: libc::c_ulong = 0x2285;
+const SG_IO: libc::Ioctl = 0x2285;
 
 // SG_IO data transfer direction: from device to host
 const SG_DXFER_FROM_DEV: i32 = -3;
diff --git a/src/platform/sinfo_io.rs b/src/platform/sinfo_io.rs
index d1c3205..864194e 100644
--- a/src/platform/sinfo_io.rs
+++ b/src/platform/sinfo_io.rs
@@ -17,27 +17,11 @@ use super::port_io::PortIo;
 
 // ── IOCTL definitions (mirrors kmod/sinfo_io/sinfo_io.h) ───────────────
 
-const SINFO_IO_MAGIC: u8 = b'S';
 const SINFO_IO_BATCH_MAX: usize = 32;
 
-// _IOW('S', 0x01, sinfo_io_setup)  = direction=1 (write), size=4, type='S', nr=1
-// _IOWR('S', 0x02, sinfo_io_reg)   = direction=3 (rw),    size=4, type='S', nr=2
-// _IOWR('S', 0x03, sinfo_io_batch) = direction=3 (rw),    size=100, type='S', nr=3
-//
-// Linux ioctl encoding: direction(2) << 30 | size(14) << 16 | type(8) << 8 | nr(8)
-const fn iow<T>(nr: u8) -> libc::c_ulong {
-    let size = std::mem::size_of::<T>() as libc::c_ulong;
-    (1 << 30) | (size << 16) | ((SINFO_IO_MAGIC as libc::c_ulong) << 8) | nr as libc::c_ulong
-}
-
-const fn iowr<T>(nr: u8) -> libc::c_ulong {
-    let size = std::mem::size_of::<T>() as libc::c_ulong;
-    (3 << 30) | (size << 16) | ((SINFO_IO_MAGIC as libc::c_ulong) << 8) | nr as libc::c_ulong
-}
-
-const SINFO_IO_SETUP: libc::c_ulong = iow::<SinfoIoSetup>(0x01);
-const SINFO_IO_READ_REG: libc::c_ulong = iowr::<SinfoIoReg>(0x02);
-const SINFO_IO_READ_BATCH: libc::c_ulong = iowr::<SinfoIoBatch>(0x03);
+const SINFO_IO_SETUP: libc::Ioctl = libc::_IOW::<SinfoIoSetup>(b'S' as u32, 0x01);
+const SINFO_IO_READ_REG: libc::Ioctl = libc::_IOWR::<SinfoIoReg>(b'S' as u32, 0x02);
+const SINFO_IO_READ_BATCH: libc::Ioctl = libc::_IOWR::<SinfoIoBatch>(b'S' as u32, 0x03);
 
 // ── Kernel-matching structs ─────────────────────────────────────────────
 
@@ -216,17 +200,6 @@ impl HwmAccess {
 mod tests {
     use super::*;
 
-    #[test]
-    fn test_ioctl_numbers() {
-        // Verify our const fn ioctl encoding matches the C macro definitions.
-        // _IOW('S', 0x01, struct sinfo_io_setup) where sizeof = 4
-        assert_eq!(SINFO_IO_SETUP, 0x4004_5301);
-        // _IOWR('S', 0x02, struct sinfo_io_reg) where sizeof = 4
-        assert_eq!(SINFO_IO_READ_REG, 0xC004_5302);
-        // _IOWR('S', 0x03, struct sinfo_io_batch) where sizeof = 100
-        assert_eq!(SINFO_IO_READ_BATCH, 0xC064_5303);
-    }
-
     #[test]
     fn test_struct_sizes() {
         assert_eq!(std::mem::size_of::<SinfoIoSetup>(), 4);
diff --git a/src/sensors/hsmp.rs b/src/sensors/hsmp.rs
index c567084..4a37341 100644
--- a/src/sensors/hsmp.rs
+++ b/src/sensors/hsmp.rs
@@ -11,12 +11,21 @@ mod inner {
 
     use crate::model::sensor::{SensorCategory, SensorId, SensorReading, SensorUnit};
 
+    #[repr(C, packed(4))]
+    struct HsmpMessage {
+        msg_id: u32,
+        num_args: u16,
+        response_sz: u16,
+        args: [u32; 8],
+        sock_ind: u16,
+    }
+
     // HSMP ioctl: _IOWR(0xF8, 0, hsmp_message)
     // The ioctl number encodes size=42 (the kernel's unpacked field sum).
     // Our #[repr(C, packed(4))] struct is 44 bytes due to trailing padding
     // on sock_ind (u16 → 4-byte boundary). The kernel reads 42 bytes via
     // copy_from_user, so the 2-byte tail padding is never accessed.
-    const HSMP_IOCTL: libc::c_ulong = 0xC02AF800;
+    const HSMP_IOCTL: libc::Ioctl = libc::_IOWR::<HsmpMessage>(0xF8, 0x0);
 
     // Message IDs
     const HSMP_TEST: u32 = 0x01;
@@ -30,15 +39,6 @@ mod inner {
     const HSMP_GET_RAILS_SVI: u32 = 0x1B;
     const HSMP_GET_SOCKET_FMAX_FMIN: u32 = 0x1C;
 
-    #[repr(C, packed(4))]
-    struct HsmpMessage {
-        msg_id: u32,
-        num_args: u16,
-        response_sz: u16,
-        args: [u32; 8],
-        sock_ind: u16,
-    }
-
     pub struct HsmpSource {
         fd: Option<File>,
     }
diff --git a/src/sensors/i2c/smbus_io.rs b/src/sensors/i2c/smbus_io.rs
index c111d58..17fb130 100644
--- a/src/sensors/i2c/smbus_io.rs
+++ b/src/sensors/i2c/smbus_io.rs
@@ -2,9 +2,9 @@ use std::fs::{File, OpenOptions};
 use std::os::unix::io::AsRawFd;
 
 // Linux I2C ioctl request codes (from <linux/i2c-dev.h>)
-const I2C_SLAVE: libc::c_ulong = 0x0703;
-const I2C_SLAVE_FORCE: libc::c_ulong = 0x0706;
-const I2C_SMBUS: libc::c_ulong = 0x0720;
+const I2C_SLAVE: libc::Ioctl = 0x0703;
+const I2C_SLAVE_FORCE: libc::Ioctl = 0x0706;
+const I2C_SMBUS: libc::Ioctl = 0x0720;
 
 // SMBus transfer direction
 const I2C_SMBUS_READ: u8 = 1;