[flashrom-gerrit] Change in flashrom[master]: buspirate: Add option for setting the aux pin

[Sean Anderson (Code Review)]

Sean Anderson has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/43608 )

Change subject: buspirate: Add option for setting the aux pin
......................................................................

buspirate: Add option for setting the aux pin

This adds a parameter to drive the aux pin low (or high if you
explicitly want the previous behavior). Some boards need to have a reset
pin driven low before the firmware can be safely flashed. With the Bus
Pirate, this is most easily done with the auxiliary pin.

Change-Id: Ieeecfdf1afc06dadda9b8f99547cd74854ca6775
Signed-off-by: Sean Anderson 
---
M buspirate_spi.c
M flashrom.8.tmpl
2 files changed, 33 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/08/43608/1

diff --git a/buspirate_spi.c b/buspirate_spi.c
index fdfc0e4..1ccb107 100644
--- a/buspirate_spi.c
+++ b/buspirate_spi.c
@@ -228,6 +228,7 @@
    int serialspeed_index = -1;
    int ret = 0;
    int pullup = 0;
+	int aux = 1;

dev = extract_programmer_param("dev");
    if (dev && !strlen(dev)) {
@@ -277,6 +278,17 @@
    }
    free(tmp);

+	tmp = extract_programmer_param("aux");
+	if (tmp) {
+		if (strcasecmp("high", tmp) == 0)
+			; /* Default */
+		else if (strcasecmp("low", tmp) == 0)
+			aux = 0;
+		else
+			msg_perr("Invalid AUX state, driving high by default.\n");
+	}
+	free(tmp);
+
    /* Default buffer size is 19: 16 bytes data, 3 bytes control. */
 #define DEFAULT_BUFSIZE (16 + 3)
    bp_commbuf = malloc(DEFAULT_BUFSIZE);
@@ -520,11 +532,18 @@
    }

/* Initial setup (SPI peripherals config): Enable power, CS high, AUX */
-	bp_commbuf[0] = 0x40 | 0x0b;
+	bp_commbuf[0] = 0x40 | 0x09;
    if (pullup == 1) {
    	bp_commbuf[0] |= (1 << 2);
    	msg_pdbg("Enabling pull-up resistors.\n");
    }
+	if (aux) {
+		bp_commbuf[0] |= (1 << 1);
+		msg_pdbg("Driving AUX high.\n");
+	} else {
+		msg_pdbg("Driving AUX low.\n");
+	}
+
    ret = buspirate_sendrecv(bp_commbuf, 1, 1);
    if (ret)
    	return 1;
diff --git a/flashrom.8.tmpl b/flashrom.8.tmpl
index db50d59..caf860c 100644
--- a/flashrom.8.tmpl
+++ b/flashrom.8.tmpl
@@ -902,6 +902,19 @@
 .URLB "http://dangerousprototypes.com/docs/Practical_guide_to_Bus_Pirate_pull-up_re..." \
 "in a guide by dangerousprototypes" .
 Only the external supply voltage (Vpu) is supported as of this writing.
+.sp
+An optional aux parameter specifies the state of the Bus Pirate auxiliary pin.
+This may be used to drive the auxiliary pin high or low before a transfer.
+Syntax is
+.sp
+.B "  flashrom -p buspirate_spi:aux=state"
+.sp
+where
+.B state
+can be
+.BR high " or " low .
+The default
+.BR state " is " high .
 .SS
 .BR "pickit2_spi " programmer
 .IP