mpsse: Always perform a general reset of the MPSSE in mpsse_open()
authorPeter Stuge <peter@stuge.se>
Sun, 28 Oct 2012 04:42:15 +0000 (28 05:42 +0100)
committerPeter Stuge <peter@stuge.se>
Tue, 30 Oct 2012 11:57:17 +0000 (30 11:57 +0000)
Per AN_135 FTDI MPSSE Basics Version 1.1, section 4.2 step 7.
http://www.ftdichip.com/Support/Documents/AppNotes/AN_135_MPSSE_Basics.pdf

This allows to stop and restart OpenOCD reliably, without needing
to power cycle the interface.

Change-Id: Ibeafe5ecfe7b2f6f82712cbc85116904407ddb36
Signed-off-by: Peter Stuge <peter@stuge.se>
Reviewed-on: http://openocd.zylin.com/939
Tested-by: jenkins
src/jtag/drivers/mpsse.c

index d6cbc84..92f9331 100644 (file)
@@ -55,6 +55,7 @@
 #define FTDI_DEVICE_OUT_REQTYPE (LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE)
 #define FTDI_DEVICE_IN_REQTYPE (0x80 | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_DEVICE)
 
+#define BITMODE_RESET 0x00
 #define BITMODE_MPSSE 0x02
 
 #define SIO_RESET_REQUEST             0x00
@@ -315,6 +316,19 @@ struct mpsse_ctx *mpsse_open(const uint16_t *vid, const uint16_t *pid, const cha
        err = libusb_control_transfer(ctx->usb_dev,
                        FTDI_DEVICE_OUT_REQTYPE,
                        SIO_SET_BITMODE_REQUEST,
+                       0x0b | (BITMODE_RESET << 8),
+                       ctx->index,
+                       NULL,
+                       0,
+                       ctx->usb_write_timeout);
+       if (err < 0) {
+               LOG_ERROR("unable to reset bitmode: %d", err);
+               goto error;
+       }
+
+       err = libusb_control_transfer(ctx->usb_dev,
+                       FTDI_DEVICE_OUT_REQTYPE,
+                       SIO_SET_BITMODE_REQUEST,
                        0x0b | (BITMODE_MPSSE << 8),
                        ctx->index,
                        NULL,