From 971c37575116302ac93ca155bd2917a7795c8548 Mon Sep 17 00:00:00 2001
From: Renze Nicolai <renze@rnplus.nl>
Date: Tue, 5 Jul 2022 20:07:38 +0200
Subject: [PATCH] Add check for flashing via esptool.py

---
 i2c_peripheral.c | 22 +++++++++++++++-------
 i2c_peripheral.h |  7 +++++--
 uart_task.c      |  7 ++++++-
 3 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/i2c_peripheral.c b/i2c_peripheral.c
index e139b18..f273c80 100644
--- a/i2c_peripheral.c
+++ b/i2c_peripheral.c
@@ -40,24 +40,24 @@ static bool    webusb_interrupt = false;
 
 static int ir_statemachine = -1;
 
-struct {
+static struct {
     uint8_t registers[256];
     bool    modified[256];
     uint8_t address;
     bool    write_in_progress;
 } i2c_registers;
 
-uint8_t i2c_controlled_gpios[] = {SAO_IO0_PIN, SAO_IO1_PIN, PROTO_0_PIN, PROTO_1_PIN};
-uint8_t input1_gpios[]         = {BUTTON_HOME, BUTTON_MENU, BUTTON_START, BUTTON_ACCEPT, BUTTON_BACK, FPGA_CDONE};
-uint8_t input2_gpios[]         = {BUTTON_JOY_A, BUTTON_JOY_B, BUTTON_JOY_C, BUTTON_JOY_D, BUTTON_JOY_E};
+static const uint8_t i2c_controlled_gpios[] = {SAO_IO0_PIN, SAO_IO1_PIN, PROTO_0_PIN, PROTO_1_PIN};
+static const uint8_t input1_gpios[]         = {BUTTON_HOME, BUTTON_MENU, BUTTON_START, BUTTON_ACCEPT, BUTTON_BACK, FPGA_CDONE};
+static const uint8_t input2_gpios[]         = {BUTTON_JOY_A, BUTTON_JOY_B, BUTTON_JOY_C, BUTTON_JOY_D, BUTTON_JOY_E};
 
 static absolute_time_t next_adc_read;
-uint8_t                next_adc_channel;
+static uint8_t         next_adc_channel;
 
-const bool i2c_registers_read_only[256] = {
+static const bool i2c_registers_read_only[256] = {
     true,  false, true,  false, false, false, true,  true,   // 0-7
     true,  true,  false, true,  true,  true,  true,  true,   // 8-15
-    false, false, false, false, false, false, false, false,  // 16-23
+    false, false, true,  false, false, true,  true,  true,   // 16-23
     true,  true,  true,  true,  true,  true,  true,  true,   // 24-31
     false, false, false, false, false, false, false, false,  // 32-39
     false, false, false, false, false, false, false, false,  // 40-47
@@ -342,3 +342,11 @@ void i2c_set_webusb_mode(uint8_t mode) {
 }
 
 void i2c_set_crash_debug_state(bool crashed, bool debug) { i2c_registers.registers[I2C_REGISTER_CRASH_DEBUG] = (crashed & 1) | ((debug << 1) & 2); }
+
+void i2c_set_reset_attempted(bool attempted) {
+    i2c_registers.registers[I2C_REGISTER_RESET_ATTEMPTED] = attempted;
+}
+
+bool i2c_get_reset_allowed() {
+    return !i2c_registers.registers[I2C_REGISTER_RESET_LOCK];
+}
diff --git a/i2c_peripheral.h b/i2c_peripheral.h
index 0998e5b..4060d14 100644
--- a/i2c_peripheral.h
+++ b/i2c_peripheral.h
@@ -21,6 +21,9 @@ void i2c_set_webusb_mode(uint8_t mode);
 
 void i2c_set_crash_debug_state(bool crashed, bool debug);
 
+void i2c_set_reset_attempted(bool attempted);
+bool i2c_get_reset_allowed();
+
 enum {
     // 0-7
     I2C_REGISTER_FW_VER,
@@ -46,8 +49,8 @@ enum {
     I2C_REGISTER_BL_TRIGGER,
     I2C_REGISTER_WEBUSB_MODE,
     I2C_REGISTER_CRASH_DEBUG,
-    I2C_REGISTER_RESERVED2,
-    I2C_REGISTER_RESERVED3,
+    I2C_REGISTER_RESET_LOCK,
+    I2C_REGISTER_RESET_ATTEMPTED,
     I2C_REGISTER_CHARGING_STATE,
     I2C_REGISTER_ADC_VALUE_TEMP_LO,
     I2C_REGISTER_ADC_VALUE_TEMP_HI,
diff --git a/uart_task.c b/uart_task.c
index 11cc486..6c1b31f 100644
--- a/uart_task.c
+++ b/uart_task.c
@@ -304,7 +304,12 @@ void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts) {
             if ((esp32_reset_state == 1) && (dtr2) && (!rts2)) esp32_reset_state = 2;
             if ((esp32_reset_state == 2) && (!dtr2) && (rts2)) esp32_reset_state = 3;
             if ((esp32_reset_state == 3) && (dtr2) && (rts2)) {
-                esp32_reset(true);
+                if (i2c_get_reset_allowed()) {
+                    esp32_reset(true);
+                } else {
+                    i2c_set_reset_attempted(true);
+                    esp32_reset(false);
+                }
             }
 
             if ((esp32_reset_app_state == 0) && ((!dtr2) && rts2)) esp32_reset_app_state = 1;