FT2232: increase read retry counts

This change is necessary to debug AT91SAM9260 on my PC with a
FT2232H dongle.

Signed-off-by: Dimitar Dimitrov <dinuxbg@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

diff --git a/src/jtag/ft2232.c b/src/jtag/ft2232.c
index cf3fc01261a465164e7c14971ff0c6268726585d..e570cbe983266a971f3beae93acfdcfc8a64a42c 100644 (file)
--- a/src/jtag/ft2232.c
+++ b/src/jtag/ft2232.c
@@ -71,6 +71,17 @@
 /* this speed value tells that RTCK is requested */
 #define RTCK_SPEED -1
 
+/*
+ * On my Athlon XP 1900+ EHCI host with FT2232H JTAG dongle I get read timeout
+ * errors with a retry count of 100. Increasing it solves the problem for me.
+ *     - Dimitar
+ *
+ * FIXME There's likely an issue with the usb_read_timeout from libftdi.
+ * Fix that (libusb? kernel? libftdi? here?) and restore the retry count
+ * to something sane.
+ */
+#define LIBFTDI_READ_RETRY_COUNT               2000
+
 #ifndef BUILD_FT2232_HIGHSPEED
  #if BUILD_FT2232_FTD2XX == 1
        enum { FT_DEVICE_2232H = 6, FT_DEVICE_4232H };
@@ -400,7 +411,7 @@ static int ft2232_read(uint8_t* buf, uint32_t size, uint32_t* bytes_read)
 
 #elif BUILD_FT2232_LIBFTDI == 1
        int retval;
-       int timeout = 100;
+       int timeout = LIBFTDI_READ_RETRY_COUNT;
        *bytes_read = 0;
 
        while ((*bytes_read < size) && timeout--)
@@ -418,9 +429,10 @@ static int ft2232_read(uint8_t* buf, uint32_t size, uint32_t* bytes_read)
 
        if (*bytes_read < size)
        {
-               LOG_ERROR("couldn't read the requested number of bytes from FT2232 device (%i < %i)",
-                         (unsigned int)(*bytes_read),
-                         (unsigned int)size);
+               LOG_ERROR("couldn't read enough bytes from "
+                               "FT2232 device (%i < %i)",
+                               (unsigned)*bytes_read,
+                               (unsigned)size);
                return ERROR_JTAG_DEVICE_ERROR;
        }
 
@@ -679,7 +691,8 @@ static int ft2232_send_and_recv(jtag_command_t* first, jtag_command_t* last)
 
        if (ft2232_expect_read)
        {
-               int timeout = 100;
+               /* FIXME this "timeout" is never changed ... */
+               int timeout = LIBFTDI_READ_RETRY_COUNT;
                ft2232_buffer_size = 0;
 
 #ifdef _DEBUG_USB_IO_
@@ -709,16 +722,21 @@ static int ft2232_send_and_recv(jtag_command_t* first, jtag_command_t* last)
 
                if (ft2232_expect_read != ft2232_buffer_size)
                {
-                       LOG_ERROR("ft2232_expect_read (%i) != ft2232_buffer_size (%i) (%i retries)", ft2232_expect_read,
+                       LOG_ERROR("ft2232_expect_read (%i) != "
+                                       "ft2232_buffer_size (%i) "
+                                       "(%i retries)",
+                                       ft2232_expect_read,
                                        ft2232_buffer_size,
-                                       100 - timeout);
+                                       LIBFTDI_READ_RETRY_COUNT - timeout);
                        ft2232_debug_dump_buffer();
 
                        exit(-1);
                }
 
 #ifdef _DEBUG_USB_COMMS_
-               LOG_DEBUG("read buffer (%i retries): %i bytes", 100 - timeout, ft2232_buffer_size);
+               LOG_DEBUG("read buffer (%i retries): %i bytes",
+                               LIBFTDI_READ_RETRY_COUNT - timeout,
+                               ft2232_buffer_size);
                ft2232_debug_dump_buffer();
 #endif
        }