#!/bin/bash
# Apply DAHDI driver patch for OpenWRT 24.10.4
# Fixes MAX macro naming issues in dahdi-linux modules
# Author: ChatGPT (for Zhe Yuan)

set -e
umask 022

PATCH_DIR="package/feeds/telephony/dahdi-linux/patches"
PATCH_FILE="$PATCH_DIR/300-fix-dahdi-max-attempts.patch"

echo "========================================"
echo " DAHDI Linux Patch Applier for OpenWRT"
echo "========================================"

# --- Check if inside OpenWRT source directory ---
if [ ! -f "feeds.conf.default" ] || [ ! -d "package" ]; then
  echo "[ERROR] This script must be run inside the OpenWRT root directory."
  echo "Please 'cd' to your OpenWRT source root and run again."
  exit 1
fi

# --- Check if dahdi patch directory exists ---
if [ ! -d "$PATCH_DIR" ]; then
  echo "[ERROR] Patch directory not found:"
  echo "  $PATCH_DIR"
  echo
  echo "Please make sure telephony feed is installed:"
  echo "  ./scripts/feeds update telephony"
  echo "  ./scripts/feeds install -a"
  exit 1
fi

# --- Create patch file ---
echo "[INFO] Writing DAHDI patch to: $PATCH_FILE"
cat > "$PATCH_FILE" <<'EOF'
--- a/drivers/dahdi/wctdm24xxp/base.c
+++ b/drivers/dahdi/wctdm24xxp/base.c
@@ -1516,16 +1516,16 @@ static int wait_access(struct wctdm *wc, struct wctdm_module *const mod)
 {
 	unsigned char data = 0;
 	int count = 0;
 
-	#define MAX 10 /* attempts */
+	#define MAX_ATTEMPTS 10 /* attempts */
 
 	/* Wait for indirect access */
-	while (count++ < MAX) {
+	while (count++ < MAX_ATTEMPTS) {
 		data = wctdm_getreg(wc, mod, I_STATUS);
 		if (!data)
 			return 0;
 	}
 
-	if (count > (MAX-1)) {
+	if (count > (MAX_ATTEMPTS-1)) {
 		dev_notice(&wc->vb.pdev->dev,
 			   " ##### Loop error (%02x) #####\n", data);
 	}

--- a/drivers/dahdi/opvxa1200/base.c
+++ b/drivers/dahdi/opvxa1200/base.c
@@ -868,12 +868,12 @@ static int wait_access(struct wctdm *wc, int card)
     long origjiffies;
     int count = 0;
 
-    #define MAX 6000 /* attempts */
+    #define MAX_ATTEMPTS 6000 /* attempts */
 
 
     origjiffies = jiffies;
     /* Wait for indirect access */
-    while (count++ < MAX)
+    while (count++ < MAX_ATTEMPTS)
 	 {
 		data = __wctdm_getreg(wc, card, I_STATUS);
 
@@ -882,7 +882,7 @@ static int wait_access(struct wctdm *wc, int card)
 
 	 }
 
-    if(count > (MAX-1)) printk(KERN_NOTICE " ##### Loop error (%02x) #####\n", data);
+    if(count > (MAX_ATTEMPTS-1)) printk(KERN_NOTICE " ##### Loop error (%02x) #####\n", data);
 
 	return 0;
 }

--- a/drivers/dahdi/wcaxx-base.c
+++ b/drivers/dahdi/wcaxx-base.c
@@ -1066,16 +1066,16 @@ static int wait_access(struct wcaxx *wc, struct wcaxx_module *const mod)
 	unsigned char data = 0;
 	int count = 0;
 
-	#define MAX 10 /* attempts */
+	#define MAX_ATTEMPTS 10 /* attempts */
 
 	/* Wait for indirect access */
-	while (count++ < MAX) {
+	while (count++ < MAX_ATTEMPTS) {
 		data = wcaxx_getreg(wc, mod, I_STATUS);
 		if (!data)
 			return 0;
 	}
 
-	if (count > (MAX-1)) {
+	if (count > (MAX_ATTEMPTS-1)) {
 		dev_notice(&wc->xb.pdev->dev,
 			   " ##### Loop error (%02x) #####\n", data);
 	}

--- a/drivers/dahdi/wctdm.c
+++ b/drivers/dahdi/wctdm.c
@@ -623,11 +623,11 @@ static int wait_access(struct wctdm *wc, int card)
     unsigned char data = 0;
     int count = 0;
 
-    #define MAX 6000 /* attempts */
+    #define MAX_ATTEMPTS 6000 /* attempts */
 
 
     /* Wait for indirect access */
-    while (count++ < MAX)
+    while (count++ < MAX_ATTEMPTS)
 	 {
 		data = __wctdm_getreg(wc, card, I_STATUS);
 
@@ -636,7 +636,7 @@ static int wait_access(struct wctdm *wc, int card)
 
 	 }
 
-    if(count > (MAX-1)) printk(KERN_NOTICE " ##### Loop error (%02x) #####\n", data);
+    if(count > (MAX_ATTEMPTS-1)) printk(KERN_NOTICE " ##### Loop error (%02x) #####\n", data);
 
 	return 0;
 }
EOF

echo "[SUCCESS] Patch written successfully!"
echo
echo "========================================"
echo "✅ DAHDI patch applied successfully!"
echo "   File: $PATCH_FILE"
echo "========================================"
echo
echo "👉 Next step:"
echo "   make package/feeds/telephony/dahdi-linux/{clean,prepare} V=s"
echo "   make package/feeds/telephony/dahdi-linux/compile V=s"
echo