package/base-files: add caldata_sysfsload_from_file()

[openwrt/openwrt.git] / package / base-files / files / lib / functions / caldata.sh

diff --git a/package/base-files/files/lib/functions/caldata.sh b/package/base-files/files/lib/functions/caldata.sh
index 5e969e3409304572c1dddc2fb35cf4d68de92966..6862da716436c64f9ff6177dbcb01a8f9959edd7 100644 (file)
--- a/package/base-files/files/lib/functions/caldata.sh
+++ b/package/base-files/files/lib/functions/caldata.sh
@@ -68,6 +68,21 @@ caldata_from_file() {
                caldata_die "failed to extract calibration data from $source"
 }
 
+caldata_sysfsload_from_file() {
+       local source=$1
+       local offset=$(($2))
+       local count=$(($3))
+
+       # test extract to /dev/null first
+       dd if=$source of=/dev/null iflag=skip_bytes bs=$count skip=$offset count=1 2>/dev/null || \
+               caldata_die "failed to extract calibration data from $source"
+
+       # can't fail now
+       echo 1 > /sys/$DEVPATH/loading
+       dd if=$source of=/sys/$DEVPATH/data iflag=skip_bytes bs=$count skip=$offset count=1 2>/dev/null
+       echo 0 > /sys/$DEVPATH/loading
+}
+
 caldata_valid() {
        local expected="$1"
        local target=$2