From 369a695bd949080933d013a48697d679d9b109e6 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jeremy@system76.com>
Date: Thu, 20 Feb 2020 21:09:10 -0700
Subject: [PATCH] Add timeout macro to simplify timeout logic

---
 tool/src/ec.rs      | 32 ++++++++------------------------
 tool/src/lib.rs     | 19 ++++++++++++++-----
 tool/src/main.rs    |  6 +++---
 tool/src/pmc.rs     | 40 ++++++++++++++++++++++++++++------------
 tool/src/timeout.rs | 23 +++++++++++++++++++++++
 5 files changed, 76 insertions(+), 44 deletions(-)

diff --git a/tool/src/ec.rs b/tool/src/ec.rs
index d53ae75..74cdc39 100644
--- a/tool/src/ec.rs
+++ b/tool/src/ec.rs
@@ -1,8 +1,11 @@
 use hwio::{Io, Pio};
 
-use crate::error::Error;
-use crate::super_io::SuperIo;
-use crate::timeout::Timeout;
+use crate::{
+    Error,
+    SuperIo,
+    Timeout,
+    timeout
+};
 
 #[derive(Clone, Copy, Debug)]
 #[repr(u8)]
@@ -96,27 +99,8 @@ impl<T: Timeout> Ec<T> {
     pub unsafe fn command(&mut self, cmd: EcCmd) -> Result<(), Error> {
         self.timeout.reset();
 
-        while self.timeout.running() {
-            match self.command_start(cmd) {
-                Ok(()) => break,
-                Err(err) => match err {
-                    Error::WouldBlock => (),
-                    _ => return Err(err)
-                },
-            }
-        }
-
-        while self.timeout.running() {
-            match self.command_finish() {
-                Ok(ok) => return Ok(ok),
-                Err(err) => match err {
-                    Error::WouldBlock => (),
-                    _ => return Err(err)
-                },
-            }
-        }
-
-        Err(Error::Timeout)
+        timeout!(self.timeout, self.command_start(cmd))?;
+        timeout!(self.timeout, self.command_finish())
     }
 
     /// Probe for EC
diff --git a/tool/src/lib.rs b/tool/src/lib.rs
index a1433c7..b0d5a2d 100644
--- a/tool/src/lib.rs
+++ b/tool/src/lib.rs
@@ -1,7 +1,16 @@
 #![no_std]
 
-pub mod ec;
-pub mod error;
-pub mod pmc;
-pub mod super_io;
-pub mod timeout;
+pub use self::ec::Ec;
+mod ec;
+
+pub use self::error::Error;
+mod error;
+
+pub use self::pmc::Pmc;
+mod pmc;
+
+pub use self::super_io::SuperIo;
+mod super_io;
+
+pub use self::timeout::Timeout;
+mod timeout;
diff --git a/tool/src/main.rs b/tool/src/main.rs
index adc1755..2298a7c 100644
--- a/tool/src/main.rs
+++ b/tool/src/main.rs
@@ -1,7 +1,7 @@
 use ectool::{
-    ec::Ec,
-    error::Error,
-    timeout::Timeout,
+    Ec,
+    Error,
+    Timeout,
 };
 use std::{
     io,
diff --git a/tool/src/pmc.rs b/tool/src/pmc.rs
index 743888e..1d755fc 100644
--- a/tool/src/pmc.rs
+++ b/tool/src/pmc.rs
@@ -1,17 +1,25 @@
 use hwio::{Io, Pio};
 
-pub struct Pmc {
+use crate::{
+    Error,
+    Timeout,
+    timeout
+};
+
+pub struct Pmc<T: Timeout> {
     data: Pio<u8>,
     cmd: Pio<u8>,
+    timeout: T,
 }
 
-impl Pmc {
+impl<T: Timeout> Pmc<T> {
     /// Create a new PMC instance. `base` identifies the data port. The command
     /// port will be `base + 4`
-    pub fn new(base: u16) -> Self {
+    pub fn new(base: u16, timeout: T) -> Self {
         Self {
             data: Pio::new(base),
             cmd: Pio::new(base + 4),
+            timeout,
         }
     }
 
@@ -26,31 +34,39 @@ impl Pmc {
     }
 
     /// Write a command to the PMC. Returns None if unable to write
-    pub unsafe fn command(&mut self, data: u8) -> Option<()> {
+    pub unsafe fn command(&mut self, data: u8) -> Result<(), Error> {
         if self.can_write() {
             self.cmd.write(data);
-            Some(())
+            Ok(())
         } else {
-            None
+            Err(Error::WouldBlock)
         }
     }
 
     /// Read data from the PMC. Returns None if unable to read
-    pub unsafe fn read(&mut self) -> Option<u8> {
+    pub unsafe fn read(&mut self) -> Result<u8, Error> {
         if self.can_read() {
-            Some(self.data.read())
+            Ok(self.data.read())
         } else {
-            None
+            Err(Error::WouldBlock)
         }
     }
 
     /// Write data to the PMC. Returns false if unable to write
-    pub unsafe fn write(&mut self, data: u8) -> Option<()> {
+    pub unsafe fn write(&mut self, data: u8) -> Result<(), Error> {
         if self.can_write() {
             self.data.write(data);
-            Some(())
+            Ok(())
         } else {
-            None
+            Err(Error::WouldBlock)
         }
     }
+
+    pub unsafe fn acpi_read(&mut self, addr: u8) -> Result<u8, Error> {
+        self.timeout.reset();
+
+        timeout!(self.timeout, self.command(0x80))?;
+        timeout!(self.timeout, self.write(addr))?;
+        timeout!(self.timeout, self.read())
+    }
 }
diff --git a/tool/src/timeout.rs b/tool/src/timeout.rs
index a4ce933..8da4b39 100644
--- a/tool/src/timeout.rs
+++ b/tool/src/timeout.rs
@@ -1,3 +1,26 @@
+#[macro_export]
+macro_rules! timeout {
+    ($t:expr, $f:expr) => {{
+        let mut result = Err($crate::Error::Timeout);
+        while $t.running() {
+            match $f {
+                Ok(ok) => {
+                    result = Ok(ok);
+                    break;
+                },
+                Err(err) => match err {
+                    $crate::Error::WouldBlock => (),
+                    _ => {
+                        result = Err(err);
+                        break;
+                    }
+                },
+            }
+        }
+        result
+    }};
+}
+
 pub trait Timeout {
     fn reset(&mut self);
     fn running(&self) -> bool;