Add user interface to activate the Bus Pirate pull-up resistors
When working with some flash chips using the Bus Pirate programmer, the
use of the Bus Pirate's on-board pull-up resistors is sometimes
necessary.
On v3 hardware the use of said pull-up resistors requires the user to apply a
voltage to the VPU pin of the Bus Pirate, and then command it to use them.
For v4 hardware which supports also fixed internal 3.3V and 5V sources no
documentation could be found.
Here is a link to information pertaining to what this patch does:
http://dangerousprototypes.com/docs/SPI_(binary)#0100wxyz_-_Configure_peripherals_w.3Dpower.2C_x.3Dpull-ups.2C_y.3DAUX.2C_z.3DCS
Bonus: small cleanup of superfluous stack variables.
Corresponding to flashrom svn r1641.
Signed-off-by: Brian Salcedo <bsalcedo@gmx.us>
Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Tested-by: Brian Salcedo <bsalcedo@gmx.us>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
diff --git a/flashrom.8 b/flashrom.8
index 102bd62..90afced 100644
--- a/flashrom.8
+++ b/flashrom.8
@@ -637,6 +637,20 @@
can be
.BR 30k ", " 125k ", " 250k ", " 1M ", " 2M ", " 2.6M ", " 4M " or " 8M
(in Hz). The default is the maximum frequency of 8 MHz.
+.sp
+An optional pullups parameter specifies the use of the Bus Pirate internal pull-up resistors. This may be
+needed if you are working with a flash ROM chip that you have physically removed from the board. Syntax is
+.sp
+.B " flashrom -p buspirate_spi:pullups=state"
+.sp
+where
+.B state
+can be
+.BR on " or " off .
+More information about the Bus Pirate pull-up resistors and their purpose is available at
+.nh
+.BR "http://dangerousprototypes.com/docs/Practical_guide_to_Bus_Pirate_pull-up_resistors " .
+Only the external supply voltage (Vpu) is supported as of this writing.
.SS
.BR "dediprog " programmer
An optional