From 290d784950b6248782b049cd9831bd6e034fd538 Mon Sep 17 00:00:00 2001
From: Josh Rahm <joshuarahm@gmail.com>
Date: Tue, 30 Sep 2025 13:06:16 -0600
Subject: Add a bunch. Neglected doing commits.

Add many different patterns, and organize it.

Add a voltage discovery subsystem to allow the ch573 to detect if it's
on 12v or 5v lights.
---
 src/gpio.c | 35 ++++++++++++++++++++++++++++-------
 1 file changed, 28 insertions(+), 7 deletions(-)

(limited to 'src/gpio.c')

diff --git a/src/gpio.c b/src/gpio.c
index e016179..b093b94 100644
--- a/src/gpio.c
+++ b/src/gpio.c
@@ -3,7 +3,24 @@
 #include "ch573/pfic.h"
 #include "isr_vector.h"
 
-void configure_gpio(gpio_pin_t pin, gpio_config_t cfg)
+/* Sets all the GPIO pins to INPUT_PULL_UP configuration. This is to reduce
+ * electrical noise in the system. */
+void gpio_init()
+{
+  // Set GPIO's to input.
+  GPIO_PORT.dir_reg.set(GPIO_PORT_A, 0x0);
+  GPIO_PORT.dir_reg.set(GPIO_PORT_B, 0x0);
+
+  // Turn off all the pull-down resistors.
+  GPIO_PORT.pd_drv_reg.set(GPIO_PORT_A, 0x0);
+  GPIO_PORT.pd_drv_reg.set(GPIO_PORT_B, 0x0);
+
+  // Turn on the pull up resistors.
+  GPIO_PORT.pu_reg.set(GPIO_PORT_A, 0xffffffff);
+  GPIO_PORT.pu_reg.set(GPIO_PORT_B, 0xffffffff);
+}
+
+void gpio_configure_pin(gpio_pin_t pin, gpio_config_t cfg)
 {
   int ipin = pin;
   struct ch573_gpio__gpio_port_t* port;
@@ -43,7 +60,7 @@ void configure_gpio(gpio_pin_t pin, gpio_config_t cfg)
   }
 }
 
-int read_gpio(gpio_pin_t pin)
+int gpio_read(gpio_pin_t pin)
 {
   int ipin = pin;
   struct ch573_gpio__gpio_port_t* port;
@@ -57,7 +74,7 @@ int read_gpio(gpio_pin_t pin)
   return !!GPIO_PORT.pin.in.get(port, ipin);
 }
 
-void set_gpio(gpio_pin_t pin, int high)
+void gpio_set(gpio_pin_t pin, int high)
 {
   int ipin = pin;
   struct ch573_gpio__gpio_port_t* port;
@@ -71,9 +88,13 @@ void set_gpio(gpio_pin_t pin, int high)
   GPIO_PORT.out.set(port, !!high, ipin);
 }
 
-void enable_alternate_function(alternate_function_t afn)
+void gpio_enable_alternate_function(alternate_function_t afn, int enable)
 {
-  GPIO_I.pin_alternate.set(GPIO, 1 << afn);
+  if (enable) {
+    GPIO_I.pin_alternate.set(GPIO, 1 << afn);
+  } else {
+    GPIO->pin_alternate &= ~(1 << afn);
+  };
 }
 
 #define PFIC ch573_pfic__pfic
@@ -83,7 +104,7 @@ static void enable_gpio_pfic(int irq)
   PFIC->interrupt_enable |= irq;
 }
 
-void enable_gpio_interrupt(gpio_pin_t pin, interrupt_mode_t int_mode)
+void gpio_enable_interrupt(gpio_pin_t pin, interrupt_mode_t int_mode)
 {
   int ipin = pin;
   struct ch573_gpio__gpio_port_t* port;
@@ -150,7 +171,7 @@ void fire_irq(volatile uint16_t* int_flag_ptr, int is_port_b)
       for (cur = &GPIO_LISTENERS_START; cur < &GPIO_LISTENERS_END; ++cur) {
         (*cur)(pin | is_port_b);
       }
-      *int_flag_ptr |= 1 << pin; // Clear the interrupt for this pin.
+      *int_flag_ptr |= 1 << pin;  // Clear the interrupt for this pin.
     }
   }
 
-- 
cgit