From 5200c3cc2c87feca2bcb973e32eaeef9808fe032 Mon Sep 17 00:00:00 2001
From: Brian Cully <bjc@kublai.com>
Date: Thu, 27 Oct 2022 20:09:08 -0400
Subject: touchpad now works over spi

---
 gdbinit       |  1 +
 src/cirque.rs | 49 +++++++++++++++++++++++++++++--------------------
 src/main.rs   | 10 +++++-----
 3 files changed, 35 insertions(+), 25 deletions(-)

diff --git a/gdbinit b/gdbinit
index fe53799..881d4bc 100644
--- a/gdbinit
+++ b/gdbinit
@@ -11,3 +11,4 @@ set remote hardware-watchpoint-limit 2
 target extended-remote psyduck:3334
 
 monitor arm semihosting enable
+mon reset init
diff --git a/src/cirque.rs b/src/cirque.rs
index 4a2686b..b19b1f4 100644
--- a/src/cirque.rs
+++ b/src/cirque.rs
@@ -1,9 +1,6 @@
 /// Support for the Cirque Pinnacle 1CA027.
 use core::cmp::{max, min};
-use embedded_hal::{
-    digital::v2::{InputPin, OutputPin},
-    spi,
-};
+use embedded_hal::{digital::v2::OutputPin, spi};
 use nb;
 use stm32f1xx_hal::rcc::Clocks;
 
@@ -116,41 +113,41 @@ impl TouchData {
     }
 
     pub fn scale_to(&mut self, width: u16, height: u16) {
-        let width_factor = width / (CLAMP_X_MAX - CLAMP_X_MIN);
-        let height_factor = height / (CLAMP_Y_MAX - CLAMP_Y_MIN);
+        let width_factor: f32 = f32::from(width) / f32::from(CLAMP_X_MAX - CLAMP_X_MIN);
+        let height_factor: f32 = f32::from(height) / f32::from(CLAMP_Y_MAX - CLAMP_Y_MIN);
 
         self.clamp();
         self.x -= CLAMP_X_MIN;
         self.y -= CLAMP_Y_MIN;
 
-        self.x *= width_factor;
-        self.y *= height_factor;
+        assert!(!width_factor.is_nan() && width_factor.is_finite());
+        assert!(!height_factor.is_nan() && height_factor.is_finite());
+        unsafe {
+            self.x = (f32::from(self.x) * width_factor).to_int_unchecked();
+            self.y = (f32::from(self.y) * height_factor).to_int_unchecked();
+        }
     }
 }
 
-pub struct Cirque<C, D>
+pub struct Cirque<C>
 where
     C: OutputPin,
-    D: InputPin,
 {
     cs_pin: C,
-    dr_pin: D,
     sysclk_speed: u32,
 }
 
-impl<C, D> Cirque<C, D>
+impl<C> Cirque<C>
 where
     C: OutputPin,
-    D: InputPin,
 {
-    pub fn new<S>(cs_pin: C, dr_pin: D, spi: &mut S, clocks: Clocks) -> nb::Result<Self, S::Error>
+    pub fn new<S>(cs_pin: C, spi: &mut S, clocks: Clocks) -> nb::Result<Self, S::Error>
     where
         S: spi::FullDuplex<u8>,
     {
         let sysclk_speed = clocks.sysclk().raw();
         let mut res = Self {
             cs_pin,
-            dr_pin,
             sysclk_speed,
         };
         res.init(spi)?;
@@ -162,10 +159,13 @@ where
         S: spi::FullDuplex<u8>,
     {
         self.cs_pin.set_high().ok();
+
+        // spin until power on reset is flagged.
+        // while self.read_flags(spi)? & 0x8 != 0x8 {}
         self.clear_flags(spi)?;
 
-        self.wr(spi, RAPAddress::SysConfig1, 0x02)?;
-        self.wr(spi, RAPAddress::FeedConfig2, 0x1f)?;
+        self.wr(spi, RAPAddress::SysConfig1, 0x00)?;
+        self.wr(spi, RAPAddress::FeedConfig2, 0x1e)?;
         self.wr(spi, RAPAddress::FeedConfig1, 0x03)?;
         self.wr(spi, RAPAddress::ZIdle, 0x05)?;
 
@@ -184,12 +184,21 @@ where
         Ok(())
     }
 
+    fn read_flags<S>(&mut self, spi: &mut S) -> nb::Result<u8, S::Error>
+    where
+        S: spi::FullDuplex<u8>,
+    {
+        let mut flags: [u8; 1] = [0xfb; 1];
+        self.rd(spi, RAPAddress::Status1, &mut flags)?;
+        Ok(flags[0])
+    }
+
     pub fn poll<S>(&mut self, spi: &mut S) -> nb::Result<TouchData, S::Error>
     where
         S: spi::FullDuplex<u8>,
     {
-        if self.dr_pin.is_high().unwrap_or(false) {
-            self.read_coords(spi)
+        if self.read_flags(spi)? & 0x4 == 0x4 {
+            Ok(self.read_coords(spi)?)
         } else {
             Err(nb::Error::WouldBlock)
         }
@@ -206,7 +215,7 @@ where
         let x = buf[2] as u16 | ((buf[4] as u16 & 0x0f) << 8);
         let y = buf[3] as u16 | ((buf[4] as u16 & 0xf0) << 4);
         let z = buf[5] & 0x3f;
-        let buttons = buf[0] & 0x3f;
+        let buttons = 0;
         let is_pressed = x != 0;
 
         assert!(x < MAX_X);
diff --git a/src/main.rs b/src/main.rs
index 02812bd..1697001 100755
--- a/src/main.rs
+++ b/src/main.rs
@@ -76,7 +76,8 @@ fn main() -> ! {
     // pa7 - mosi1
 
     logln!("init trackpad");
-    let dr_pin = gpiob.pb0;
+    // TODO: hook an interrupt up to the dr pin to trigger a poll.
+    //let dr_pin = gpiob.pb1.into_pull_down_input(&mut gpiob.crl);
     let sck_pin = gpioa.pa5.into_alternate_push_pull(&mut gpioa.crl);
     let miso_pin = gpioa.pa6;
     let mosi_pin = gpioa.pa7.into_alternate_push_pull(&mut gpioa.crl);
@@ -86,10 +87,10 @@ fn main() -> ! {
         (sck_pin, miso_pin, mosi_pin),
         &mut afio.mapr,
         spi::MODE_1,
-        1_500_000.Hz(),
+        1_000_000.Hz(), // pinnacle supports up to 13mhz
         clocks,
     );
-    let mut cirque = match Cirque::new(cs_pin, dr_pin, &mut spi, clocks) {
+    let mut cirque = match Cirque::new(cs_pin, &mut spi, clocks) {
         Ok(c) => c,
         Err(e) => {
             logln!("err: {:?}", e);
@@ -126,8 +127,7 @@ fn main() -> ! {
 
     logln!("luchie started!");
     loop {
-        logln!(".");
-
+        // logln!(".");
         if let Ok(mut td) = cirque.poll(&mut spi) {
             td.scale_to(1920, 1080);
             logln!("td: {:?}", td);
-- 
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