From b07a16ed5cfde7123221b7fb59df8de492066619 Mon Sep 17 00:00:00 2001
From: Daniel Kao <daniel.m.kao@gmail.com>
Date: Sat, 14 May 2022 22:14:45 -0700
Subject: [PATCH] Add a limit to do-while loops in Cirque driver

Duration for these operations undocumented (does somebody know?)
At least let them terminate rather than freeze up the keyboard when
trackpad is disconnected.

TODO: Do early return based on touch_init as well, or instead of this.
---
 drivers/sensors/cirque_pinnacle.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/sensors/cirque_pinnacle.c b/drivers/sensors/cirque_pinnacle.c
index fb01572af5e5..93b0b3e8339f 100644
--- a/drivers/sensors/cirque_pinnacle.c
+++ b/drivers/sensors/cirque_pinnacle.c
@@ -137,6 +137,7 @@ void cirque_pinnacle_enable_feed(bool feedEnable) {
 // stores values in <*data>
 void ERA_ReadBytes(uint16_t address, uint8_t* data, uint16_t count) {
     uint8_t ERAControlValue = 0xFF;
+    uint16_t retry = 0;
 
     cirque_pinnacle_enable_feed(false); // Disable feed
 
@@ -149,7 +150,7 @@ void ERA_ReadBytes(uint16_t address, uint8_t* data, uint16_t count) {
         // Wait for status register 0x1E to clear
         do {
             RAP_ReadBytes(ERA_CONTROL, &ERAControlValue, 1);
-        } while (ERAControlValue != 0x00);
+        } while ((ERAControlValue != 0x00) && (++retry != 0));
 
         RAP_ReadBytes(ERA_VALUE, data + i, 1);
 
@@ -160,6 +161,7 @@ void ERA_ReadBytes(uint16_t address, uint8_t* data, uint16_t count) {
 // Writes a byte, <data>, to an extended register at <address> (16-bit address)
 void ERA_WriteByte(uint16_t address, uint8_t data) {
     uint8_t ERAControlValue = 0xFF;
+    uint16_t retry = 0;
 
     cirque_pinnacle_enable_feed(false); // Disable feed
 
@@ -173,7 +175,7 @@ void ERA_WriteByte(uint16_t address, uint8_t data) {
     // Wait for status register 0x1E to clear
     do {
         RAP_ReadBytes(ERA_CONTROL, &ERAControlValue, 1);
-    } while (ERAControlValue != 0x00);
+    } while ((ERAControlValue != 0x00) && (++retry != 0));
 
     cirque_pinnacle_clear_flags();
 }
@@ -204,6 +206,7 @@ void cirque_pinnacle_tune_edge_sensitivity(void) {
 // Perform calibration
 void cirque_pinnacle_calibrate(void) {
     uint8_t calconfig;
+    uint16_t retry = 0;
 
     RAP_ReadBytes(CALIBRATION_CONFIG_1, &calconfig, 1);
     calconfig |= 0x01;
@@ -211,7 +214,7 @@ void cirque_pinnacle_calibrate(void) {
 
     do {
         RAP_ReadBytes(CALIBRATION_CONFIG_1, &calconfig, 1);
-    } while (calconfig & 0x01);
+    } while ((calconfig & 0x01) && (++retry != 0));
 
     cirque_pinnacle_clear_flags();
 }