From b67644ba35ee4879d002dafef85df69000c3b83f Mon Sep 17 00:00:00 2001
From: Maxim Poliakovski <maximumspatium@googlemail.com>
Date: Thu, 11 Aug 2022 01:43:08 +0200
Subject: [PATCH] athens: support ID reading & dot clock disabling.

---
 devices/common/i2c/athens.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/devices/common/i2c/athens.cpp b/devices/common/i2c/athens.cpp
index 2edd25d..1cc242b 100644
--- a/devices/common/i2c/athens.cpp
+++ b/devices/common/i2c/athens.cpp
@@ -85,8 +85,8 @@ bool AthensClocks::send_byte(uint8_t data)
 
 bool AthensClocks::receive_byte(uint8_t* p_data)
 {
-    LOG_F(INFO, "Athens: receive_byte called");
-    return false; // return NACK for now
+    *p_data = 0x41; // return my ID (value has been guessed)
+    return true;
 }
 
 int AthensClocks::get_sys_freq()
@@ -101,6 +101,11 @@ int AthensClocks::get_dot_freq()
         22, 27, 28, 31, 35, 37, 38, 42, 49, 55, 56, 78,  125
     };
 
+    if (this->regs[AthensRegs::P2_MUX2] & 0xC0) {
+        LOG_F(INFO, "Athens: dot clock disabled");
+        return 0;
+    }
+
     float out_freq = 0.0f;
 
     int d2 = this->regs[AthensRegs::D2];