From ac2bf5f638e470c60b812b20af54b296aab8ab27 Mon Sep 17 00:00:00 2001
From: turmary <turmary@126.com>
Date: Wed, 30 Sep 2020 10:39:23 +0800
Subject: [PATCH 1/2] Move: dkms module removing to the position before kernel
 update

---
 install.sh | 37 +++++++++++++++++++++++++------------
 1 file changed, 25 insertions(+), 12 deletions(-)

diff --git a/install.sh b/install.sh
index 4e76a45..ac6ebc7 100755
--- a/install.sh
+++ b/install.sh
@@ -201,11 +201,34 @@ function install_kernel() {
   }
 }
 
+function uninstall_module {
+  src=$1
+  mod=$2
+
+  if [[ -d /var/lib/dkms/$mod/$ver/$marker ]]; then
+    rmdir /var/lib/dkms/$mod/$ver/$marker
+  fi
+
+  if [[ -e /usr/src/$mod-$ver || -e /var/lib/dkms/$mod/$ver ]]; then
+    dkms remove --force -m $mod -v $ver --all
+    rm -rf /usr/src/$mod-$ver
+  fi
+
+  return 0
+}
+
 # update and install required packages
-which apt &>/dev/null
-if [[ $? -eq 0 ]]; then
+which apt &>/dev/null; r=$?
+if [[ $r -eq 0 ]]; then
+  echo -e "\n### Install required tool packages"
   apt update -y
   apt-get -y install dkms git i2c-tools libasound2-plugins
+fi
+
+echo -e "\n### Uninstall previous dkms module"
+uninstall_module "./" "seeed-voicecard"
+
+if [[ $r -eq 0 ]]; then
   echo -e "\n### Install required kernel package"
   install_kernel
   # rpi-update checker
@@ -232,15 +255,6 @@ function install_module {
   src=$1
   mod=$2
 
-  if [[ -d /var/lib/dkms/$mod/$ver/$marker ]]; then
-    rmdir /var/lib/dkms/$mod/$ver/$marker
-  fi
-
-  if [[ -e /usr/src/$mod-$ver || -e /var/lib/dkms/$mod/$ver ]]; then
-    dkms remove --force -m $mod -v $ver --all
-    rm -rf /usr/src/$mod-$ver
-  fi
-
   mkdir -p /usr/src/$mod-$ver
   cp -a $src/* /usr/src/$mod-$ver/
 
@@ -261,7 +275,6 @@ function install_module {
 echo -e "\n### Install sound card driver"
 install_module "./" "seeed-voicecard"
 
-
 # install dtbos
 echo -e "\n### Install device tree overlays"
 cp -v seeed-2mic-voicecard.dtbo $OVERLAYS

From 8cce4e8ffa77e1e2b89812e5e2ccf6cfbc1086cf Mon Sep 17 00:00:00 2001
From: turmary <turmary@126.com>
Date: Wed, 30 Sep 2020 15:04:47 +0800
Subject: [PATCH 2/2] Add: document about "query sound card number"

---
 README.md | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/README.md b/README.md
index dcd158e..e884227 100644
--- a/README.md
+++ b/README.md
@@ -196,7 +196,22 @@ plughw:CARD=seeed8micvoicec,DEV=0
 In contrast to 6-Mics Circular Array Kit for Raspberry Pi,
 the difference is only first 4 input channels are valid capture data.
 
+
 ### Usage:
+
+```bash
+#Query sound card number
+# The sound card number used as arecord/aplay argument,
+# ( like '-D hw:N' and '-D plughw:N', where N is the number )
+# could be found by command:
+  aplay -l
+#or
+  arecord -l
+# Find the line in the command output which near below form:
+card 1: seeed2micvoicec [seeed-2mic-voicecard], device 0: ...
+# The number between first word `card` and char `:` is the Sound Card Number, here it's 1.
+```
+
 ```bash
 #for ReSpeaker 2-mic
 #It will capture sound an playback on hw:1