ft2232: simplify ft2232_read_scan

diff --git a/src/jtag/drivers/ft2232.c b/src/jtag/drivers/ft2232.c
index bc8463e6e5affefb9fa57732a81214fa3f28a880..9d40b1c040f5790ccef5e3a1fa7eaca2404b45dc 100644 (file)
--- a/src/jtag/drivers/ft2232.c
+++ b/src/jtag/drivers/ft2232.c
@@ -714,23 +714,24 @@ static void ft2232_end_state(tap_state_t state)
 
 static void ft2232_read_scan(enum scan_type type, uint8_t* buffer, int scan_size)
 {
-       int num_bytes = (scan_size + 7) / 8;
-       int bits_left = scan_size;
-       int cur_byte  = 0;
+       int num_bytes = scan_size / 8;
+       int bits_left = scan_size % 8;
+       int cur_byte;
 
-       while (num_bytes-- > 1)
+       for (cur_byte = 0; cur_byte < num_bytes; cur_byte++)
        {
-               buffer[cur_byte++] = buffer_read();
-               bits_left -= 8;
+               buffer[cur_byte] = buffer_read();
        }
 
-       buffer[cur_byte] = 0x0;
-
-       /* There is one more partial byte left from the clock data in/out instructions */
+       /* Manage partial byte left from the clock data in/out instructions, if any */
        if (bits_left > 1)
        {
                buffer[cur_byte] = buffer_read() >> 1;
        }
+       else
+       {
+               buffer[cur_byte] = 0x0;
+       }
        /* This shift depends on the length of the clock data to tms instruction, insterted at end of the scan, now fixed to a two step transition in ft2232_add_scan */
        buffer[cur_byte] = (buffer[cur_byte] | (((buffer_read()) << 1) & 0x80)) >> (8 - bits_left);
 }