rc: start drivers for attached BeagleBone Capes

BeagleBone Capes add additional hardware to the BeagleBone to
improve functionality.

This patch probes the third i2c bus for capes and loads the
appropriate drivers for each detected cape. Currently only
the 'BeagleBone Weather' cape is supported.

Change-Id: Id8c133810db6de7c21625c2d5a794b8874673a0f

distrib/sets/lists/minix/md.evbarm

@@ -4,6 +4,8 @@
 ./boot/minix/.temp/mod10_vm		minix-sys
 ./boot/minix/.temp/mod11_pfs		minix-sys
 ./boot/minix/.temp/mod12_init		minix-sys
+./etc/rc.capes				minix-sys
+./etc/rc.capes/BB-BONE-WTHR-01		minix-sys
 ./etc/system.conf.d/lan8710a		minix-sys
 ./multiboot/mod07_log			minix-sys
 ./multiboot/mod08_tty			minix-sys

etc/Makefile

@@ -458,6 +458,11 @@ install-etc-files-safe: .PHONY .MAKE check_DESTDIR MAKEDEV
 	fi; \
 	${INSTALL_FILE} -o ${owner} -g ${group} -m ${mode} ${sdir}${files} ${tdir};
 .endfor
+.if ${MACHINE_ARCH} == "earm"
+	${_MKMSG_INSTALL} ${DESTDIR}/etc/rc.capes
+	${INSTALL_DIR} ${DESTDIR}/etc/rc.capes
+	${INSTALL_FILE} -m ${BINMODE} -o ${BINOWN} -g ${BINGRP} ${NETBSDSRCDIR}/etc/rc.capes/* ${DESTDIR}/etc/rc.capes
+.endif # Minix/earm specific
 .for subdir in . defaults mtree
 	${MAKEDIRTARGET} ${subdir} configinstall
 .endfor

etc/rc.capes/BB-BONE-WTHR-01

@@ -0,0 +1,19 @@
+#!/bin/sh
+#
+# Start-up script for the BeagleBone Weather cape.
+
+# TSL2550 Ambient Light Sensor
+test -e /dev/tsl2550b3s39 || (cd /dev && MAKEDEV tsl2550b3s39)
+/bin/service up /usr/sbin/tsl2550 -dev /dev/tsl2550b3s39 \
+	-label tsl2550.3.39 -args 'bus=3 address=0x39' && echo -n " tsl2550"
+
+# SHT21 Temperature and Humidity Sensor
+test -e /dev/sht21b3s40 || (cd /dev && MAKEDEV sht21b3s40)
+/bin/service up /usr/sbin/sht21 -dev /dev/sht21b3s40 \
+	-label sht21.3.40 -args 'bus=3 address=0x40' && echo -n " sht21"
+
+# BMP085 Temperature and Pressure Sensor
+test -e /dev/bmp085b3s77 || (cd /dev && MAKEDEV bmp085b3s77)
+/bin/service up /usr/sbin/bmp085 -dev /dev/bmp085b3s77 \
+	-label bmp085.3.77 -args 'bus=3 address=0x77' && echo -n " bmp085"
+

etc/usr/rc

@@ -112,6 +112,49 @@ get_eth_labels() {
     grep -v '^vlan_'
 }
 
+# Detect expansion boards on the BeagleBone and load the proper drivers.
+capemgr() {
+
+    # Probe each possible cape EEPROM slave address for a BeagleBone cape.
+    for slave_addr in 54 55 56 57
+    do
+
+        # See if there is a readable EEPROM with address ${slave_addr}.
+        eepromread -f /dev/i2c-3 -a 0x${slave_addr} > /dev/null 2>&1
+        RESULT=$?
+	if [ $RESULT -eq 0 ]
+	then
+
+	    # Found an alive EEPROM. Try reading the cape name.
+            CAPE=`eepromread -i -f /dev/i2c-3 -a 0x${slave_addr} | \
+	        sed -n 's/^PART_NUMBER     : \(.*\)$/\1/p' | \
+		sed -e 's/\.*$//g'` # Strip trailing periods.
+
+	    # Look for a cape specific RC script.
+            if [ -x /etc/rc.capes/${CAPE} ]
+	    then
+
+	        # CAT24C256 EEPROM -- all capes have this chip.
+		test -e /dev/eepromb3s${slave_addr} || \
+		    (cd /dev && MAKEDEV eepromb3s${slave_addr})
+		up cat24c256 -dev /dev/eepromb3s${slave_addr} \
+		    -label cat24c256.3.${slave_addr} \
+		    -args "bus=3 address=0x${slave_addr}"
+
+                # Load the drivers for the cape and do any other configuration.
+		. "/etc/rc.capes/${CAPE}"
+
+	    else
+
+		echo ""
+	        echo "** UNSUPPORTED CAPE: ${CAPE}"
+		echo ""
+
+	    fi
+	fi
+    done
+}
+
 DAEMONS=/etc/rc.daemons
 
 case $action in
@@ -230,6 +273,9 @@ start)
 				# fb hasn't been ported to AM335X yet.
 			fi
 
+			# Detect expansion boards and start drivers.
+			capemgr
+
 			;;
 
 		A335BNLT)
@@ -255,6 +301,9 @@ start)
 			#up fb -dev /dev/fb0 -args edid.0=tda19988.1.3470
 			# fb hasn't been ported to AM335X yet.
 
+			# Detect expansion boards and start drivers.
+			capemgr
+
 			;;
 
 		UNKNOWN)