diff options
| -rw-r--r-- | drivers/usb/serial/cp2101.c | 92 |
1 files changed, 52 insertions, 40 deletions
diff --git a/drivers/usb/serial/cp2101.c b/drivers/usb/serial/cp2101.c index 9b4082b58c5..9b56e35aee4 100644 --- a/drivers/usb/serial/cp2101.c +++ b/drivers/usb/serial/cp2101.c @@ -31,7 +31,7 @@ /* * Version Information */ -#define DRIVER_VERSION "v0.07" +#define DRIVER_VERSION "v0.08" #define DRIVER_DESC "Silicon Labs CP2101/CP2102 RS232 serial adaptor driver" /* @@ -301,6 +301,47 @@ static inline int cp2101_set_config_single(struct usb_serial_port *port, return cp2101_set_config(port, request, &data, 2); } +/* + * cp2101_quantise_baudrate + * Quantises the baud rate as per AN205 Table 1 + */ +static unsigned int cp2101_quantise_baudrate(unsigned int baud) { + if (baud <= 56) baud = 0; + else if (baud <= 300) baud = 300; + else if (baud <= 600) baud = 600; + else if (baud <= 1200) baud = 1200; + else if (baud <= 1800) baud = 1800; + else if (baud <= 2400) baud = 2400; + else if (baud <= 4000) baud = 4000; + else if (baud <= 4803) baud = 4800; + else if (baud <= 7207) baud = 7200; + else if (baud <= 9612) baud = 9600; + else if (baud <= 14428) baud = 14400; + else if (baud <= 16062) baud = 16000; + else if (baud <= 19250) baud = 19200; + else if (baud <= 28912) baud = 28800; + else if (baud <= 38601) baud = 38400; + else if (baud <= 51558) baud = 51200; + else if (baud <= 56280) baud = 56000; + else if (baud <= 58053) baud = 57600; + else if (baud <= 64111) baud = 64000; + else if (baud <= 77608) baud = 76800; + else if (baud <= 117028) baud = 115200; + else if (baud <= 129347) baud = 128000; + else if (baud <= 156868) baud = 153600; + else if (baud <= 237832) baud = 230400; + else if (baud <= 254234) baud = 250000; + else if (baud <= 273066) baud = 256000; + else if (baud <= 491520) baud = 460800; + else if (baud <= 567138) baud = 500000; + else if (baud <= 670254) baud = 576000; + else if (baud <= 1053257) baud = 921600; + else if (baud <= 1474560) baud = 1228800; + else if (baud <= 2457600) baud = 1843200; + else baud = 3686400; + return baud; +} + static int cp2101_open(struct tty_struct *tty, struct usb_serial_port *port, struct file *filp) { @@ -388,7 +429,7 @@ static void cp2101_get_termios (struct tty_struct *tty) cp2101_get_config(port, CP2101_BAUDRATE, &baud, 2); /* Convert to baudrate */ if (baud) - baud = BAUD_RATE_GEN_FREQ / baud; + baud = cp2101_quantise_baudrate((BAUD_RATE_GEN_FREQ + baud/2)/ baud); dbg("%s - baud rate = %d", __func__, baud); @@ -517,46 +558,17 @@ static void cp2101_set_termios(struct tty_struct *tty, tty->termios->c_cflag &= ~CMSPAR; cflag = tty->termios->c_cflag; old_cflag = old_termios->c_cflag; - baud = tty_get_baud_rate(tty); + baud = cp2101_quantise_baudrate(tty_get_baud_rate(tty)); /* If the baud rate is to be updated*/ - if (baud != tty_termios_baud_rate(old_termios)) { - switch (baud) { - case 0: - case 600: - case 1200: - case 1800: - case 2400: - case 4800: - case 7200: - case 9600: - case 14400: - case 19200: - case 28800: - case 38400: - case 55854: - case 57600: - case 115200: - case 127117: - case 230400: - case 460800: - case 921600: - case 3686400: - break; - default: - baud = 9600; - break; - } - - if (baud) { - dbg("%s - Setting baud rate to %d baud", __func__, - baud); - if (cp2101_set_config_single(port, CP2101_BAUDRATE, - (BAUD_RATE_GEN_FREQ / baud))) { - dev_err(&port->dev, "Baud rate requested not " - "supported by device\n"); - baud = tty_termios_baud_rate(old_termios); - } + if (baud != tty_termios_baud_rate(old_termios) && baud != 0) { + dbg("%s - Setting baud rate to %d baud", __func__, + baud); + if (cp2101_set_config_single(port, CP2101_BAUDRATE, + ((BAUD_RATE_GEN_FREQ + baud/2) / baud))) { + dev_err(&port->dev, "Baud rate requested not " + "supported by device\n"); + baud = tty_termios_baud_rate(old_termios); } } /* Report back the resulting baud rate */ |