diff --git a/buspirate_spi.c b/buspirate_spi.c
index ae939e3..39b9c52 100644
--- a/buspirate_spi.c
+++ b/buspirate_spi.c
@@ -228,6 +228,7 @@
 	int serialspeed_index = -1;
 	int ret = 0;
 	int pullup = 0;
+	int psu = 0;
 
 	dev = extract_programmer_param("dev");
 	if (dev && !strlen(dev)) {
@@ -277,6 +278,17 @@
 	}
 	free(tmp);
 
+	tmp = extract_programmer_param("psus");
+	if (tmp) {
+		if (strcasecmp("on", tmp) == 0)
+			psu = 1;
+		else if (strcasecmp("off", tmp) == 0)
+			; // ignore
+		else
+			msg_perr("Invalid psus state, not enabling.\n");
+	}
+	free(tmp);
+
 	/* Default buffer size is 19: 16 bytes data, 3 bytes control. */
 #define DEFAULT_BUFSIZE (16 + 3)
 	bp_commbuf = malloc(DEFAULT_BUFSIZE);
@@ -527,6 +539,10 @@
 		bp_commbuf[0] |= (1 << 2);
 		msg_pdbg("Enabling pull-up resistors.\n");
 	}
+	if (psu == 1) {
+		bp_commbuf[0] |= (1 << 3);
+		msg_pdbg("Enabling PSUs.\n");
+	}
 	ret = buspirate_sendrecv(bp_commbuf, 1, 1);
 	if (ret) {
 		ret = 1;
diff --git a/flashrom.8.tmpl b/flashrom.8.tmpl
index e67cdea..9ec4d77 100644
--- a/flashrom.8.tmpl
+++ b/flashrom.8.tmpl
@@ -890,7 +890,21 @@
 More information about the Bus Pirate pull-up resistors and their purpose is available
 .URLB "http://dangerousprototypes.com/docs/Practical_guide_to_Bus_Pirate_pull-up_resistors" \
 "in a guide by dangerousprototypes" .
-Only the external supply voltage (Vpu) is supported as of this writing.
+.sp
+The state of the Bus Pirate power supply pins is controllable through an optional
+.B psus
+parameter. Syntax is
+.sp
+.B "  flashrom -p buspirate_spi:psus=state"
+.sp
+where
+.B state
+can be
+.BR on " or " off .
+This allows the bus pirate to power the ROM chip directly. This may also be used to provide the
+required pullup voltage (when using the
+.B pullups
+option), by connecting the Bus Pirate's Vpu input to the appropriate Vcc pin.
 .SS
 .BR "pickit2_spi " programmer
 .IP