diff options
| -rw-r--r-- | ft2232_spi.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/ft2232_spi.c b/ft2232_spi.c index 87e60579..65ff4490 100644 --- a/ft2232_spi.c +++ b/ft2232_spi.c @@ -110,7 +110,8 @@ static const char *get_ft2232_devicename(int ft2232_vid, int ft2232_type) { int i; for (i = 0; devs_ft2232spi[i].vendor_name != NULL; i++) { - if ((devs_ft2232spi[i].device_id == ft2232_type) && (devs_ft2232spi[i].vendor_id == ft2232_vid)) + if ((devs_ft2232spi[i].device_id == ft2232_type) + && (devs_ft2232spi[i].vendor_id == ft2232_vid)) return devs_ft2232spi[i].device_name; } return "unknown device"; @@ -120,7 +121,8 @@ static const char *get_ft2232_vendorname(int ft2232_vid, int ft2232_type) { int i; for (i = 0; devs_ft2232spi[i].vendor_name != NULL; i++) { - if ((devs_ft2232spi[i].device_id == ft2232_type) && (devs_ft2232spi[i].vendor_id == ft2232_vid)) + if ((devs_ft2232spi[i].device_id == ft2232_type) + && (devs_ft2232spi[i].vendor_id == ft2232_vid)) return devs_ft2232spi[i].vendor_name; } return "unknown vendor"; @@ -132,7 +134,8 @@ static int send_buf(struct ftdi_context *ftdic, const unsigned char *buf, int r; r = ftdi_write_data(ftdic, (unsigned char *) buf, size); if (r < 0) { - msg_perr("ftdi_write_data: %d, %s\n", r, ftdi_get_error_string(ftdic)); + msg_perr("ftdi_write_data: %d, %s\n", r, + ftdi_get_error_string(ftdic)); return 1; } return 0; @@ -146,7 +149,8 @@ static int get_buf(struct ftdi_context *ftdic, const unsigned char *buf, while (size > 0) { r = ftdi_read_data(ftdic, (unsigned char *) buf, size); if (r < 0) { - msg_perr("ftdi_read_data: %d, %s\n", r, ftdi_get_error_string(ftdic)); + msg_perr("ftdi_read_data: %d, %s\n", r, + ftdi_get_error_string(ftdic)); return 1; } buf += r; @@ -183,8 +187,8 @@ int ft2232_spi_init(void) enum ftdi_interface ft2232_interface = INTERFACE_A; /* * The 'H' chips can run with an internal clock of either 12 MHz or 60 MHz, - * but the non-H chips can only run at 12 MHz. We enable the divide-by-5 - * prescaler on the former to run on the same speed. + * but the non-H chips can only run at 12 MHz. We disable the divide-by-5 + * prescaler on 'H' chips so they run at 60MHz. */ uint8_t clock_5x = 1; /* In addition to the prescaler mentioned above there is also another @@ -193,7 +197,8 @@ int ft2232_spi_init(void) * div = (1 + x) * 2 <-> x = div / 2 - 1 * Hence the expressible divisors are all even numbers between 2 and * 2^17 (=131072) resulting in SCK frequencies of 6 MHz down to about - * 92 Hz for 12 MHz inputs. + * 92 Hz for 12 MHz inputs and 30 MHz down to about 458 Hz for 60 MHz + * inputs. */ uint32_t divisor = DEFAULT_DIVISOR; int f; @@ -381,7 +386,8 @@ int ft2232_spi_init(void) free(arg); if (f < 0 && f != -5) { - msg_perr("Unable to open FTDI device: %d (%s).\n", f, ftdi_get_error_string(ftdic)); + msg_perr("Unable to open FTDI device: %d (%s)\n", f, + ftdi_get_error_string(ftdic)); return -4; } @@ -408,7 +414,7 @@ int ft2232_spi_init(void) if (clock_5x) { msg_pdbg("Disable divide-by-5 front stage\n"); - buf[0] = 0x8a; /* Disable divide-by-5. DIS_DIV_5 in newer libftdi */ + buf[0] = DIS_DIV_5; if (send_buf(ftdic, buf, 1)) { ret = -5; goto ftdi_err; @@ -453,7 +459,8 @@ int ft2232_spi_init(void) ftdi_err: if ((f = ftdi_usb_close(ftdic)) < 0) { - msg_perr("Unable to close FTDI device: %d (%s)\n", f, ftdi_get_error_string(ftdic)); + msg_perr("Unable to close FTDI device: %d (%s)\n", f, + ftdi_get_error_string(ftdic)); } return ret; } |