Gabor Juhos 2dff8ad926 tty/serial/ar933x_uart: fix baud rate calculation ...

The UART of the AR933x SoC implements a fractional divisor
for generating the desired baud rate.

The current code uses a fixed value for the fractional
part of the divisor, and this leads to improperly
calculated baud rates:

   baud    scale   step  real baud         diff
     300   5207*   8192     17756     17456   5818.66%
     600   2603*   8192     35511     34911   5818.50%
    1200   1301*   8192     71023     69823   5818.58%
    2400    650*   8192     11241      8841    368.37%
    4800    324*   8192     22645     17845    371.77%
    9600    161    8192      9645        45      0.46%
   14400    107    8192     14468        68      0.47%
   19200     80    8192     19290        90      0.46%
   28800     53    8192     28935       135      0.46%
   38400     39    8192     39063       663      1.72%
   57600     26    8192     57870       270      0.46%
  115200     12    8192    120192      4992      4.33%
  230400      5    8192    260417     30017     13.02%
  460800      2    8192    520833     60033     13.02%
  921600      0    8192   1562500    640900     69.93%

After the patch, the integer and fractional parts of the
divisor will be calculated dynamically. This ensures that
the UART will use correct baud rates:

   baud    scale   step  real baud         diff
     300      6      11       300         0      0.00%
     600     54     173       600         0      0.00%
    1200     30     195      1200         0      0.00%
    2400     30     390      2400         0      0.00%
    4800     48    1233      4800         0      0.00%
    9600     78    3976      9600         0      0.00%
   14400     98    7474     14400         0      0.00%
   19200     55    5637     19200         0      0.00%
   28800    130   19780     28800         0      0.00%
   38400     36    7449     38400         0      0.00%
   57600     78   23857     57600         0      0.00%
  115200     43   26575    115200         0      0.00%
  230400     23   28991    230400         0      0.00%
  460800     11   28991    460800         0      0.00%
  921600      5   28991    921599        -1      0.00%

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2012-11-15 17:15:02 -08:00

..

hvc

TTY: hvcs: fix missing unlock on error in hvcs_initialize()

2012-10-24 11:37:02 -07:00

ipwireless

ipwireless: don't oops if we run out of space

2012-11-15 16:53:15 -08:00

serial

tty/serial/ar933x_uart: fix baud rate calculation

2012-11-15 17:15:02 -08:00

vt

TTY: vt, fix paste_selection ldisc handling

2012-10-22 16:50:53 -07:00

amiserial.c

serial: add a new helper function

2012-09-05 13:28:35 -07:00

bfin_jtag_comm.c

TTY: use tty_port_link_device

2012-08-13 16:50:19 -07:00

cyclades.c

serial: add a new helper function

2012-09-05 13:28:35 -07:00

ehv_bytechan.c

TTY: use tty_port_register_device

2012-08-13 16:50:19 -07:00

isicom.c

serial: add a new helper function

2012-09-05 13:28:35 -07:00

Kconfig

tty/serial: put (EXPERIMENTAL) marking back on N_GSM and SERIAL_IFX6X60

2012-09-18 17:17:56 +01:00

Makefile

tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver

2011-08-23 10:32:56 -07:00

moxa.c

moxa: dcd handling of CLOCAL is backwards

2012-11-15 16:53:14 -08:00

moxa.h

tty: move a number of tty drivers from drivers/char/ to drivers/tty/

2011-02-22 16:14:56 -08:00

mxser.c

serial: add a new helper function

2012-09-05 13:28:35 -07:00

mxser.h

Fix common misspellings

2011-03-31 11:26:23 -03:00

n_gsm.c

tty: n_gsm: Fix incorrect debug display

2012-09-17 04:45:30 -07:00

n_hdlc.c

Remove all #inclusions of asm/system.h

2012-03-28 18:30:03 +01:00

n_r3964.c

tty: localise the lock

2012-08-10 12:55:47 -07:00

n_tracerouter.c

n_tracerouter and n_tracesink ldisc additions.

2011-05-13 16:31:00 -07:00

n_tracesink.c

n_tracerouter and n_tracesink ldisc additions.

2011-05-13 16:31:00 -07:00

n_tracesink.h

n_tracerouter and n_tracesink ldisc additions.

2011-05-13 16:31:00 -07:00

n_tty.c

tty: add missing newlines to WARN_RATELIMIT

2012-10-25 11:30:27 -07:00

nozomi.c

TTY: use tty_port_register_device

2012-08-13 16:50:19 -07:00

pty.c

tty: Add get- ioctls to fetch tty status v3

2012-10-25 12:07:18 -07:00

rocket_int.h

tty: move a number of tty drivers from drivers/char/ to drivers/tty/

2011-02-22 16:14:56 -08:00

rocket.c

TTY: use tty_port_register_device

2012-08-13 16:50:19 -07:00

rocket.h

tty: move a number of tty drivers from drivers/char/ to drivers/tty/

2011-02-22 16:14:56 -08:00

synclink_gt.c

serial: add a new helper function

2012-09-05 13:28:35 -07:00

synclink.c

serial: add a new helper function

2012-09-05 13:28:35 -07:00

synclinkmp.c

serial: add a new helper function

2012-09-05 13:28:35 -07:00

sysrq.c

mm, oom: ensure sysrq+f always passes valid zonelist

2012-11-15 17:13:48 -08:00

tty_audit.c

TTY: audit, stop accessing tty->icount

2012-10-22 16:50:54 -07:00

tty_buffer.c

tty: add missing newlines to WARN_RATELIMIT

2012-10-25 11:30:27 -07:00

tty_io.c

tty: Add get- ioctls to fetch tty status v3

2012-10-25 12:07:18 -07:00

tty_ioctl.c

tty: pty - Move TIOCPKT handling into pty.c

2012-10-25 12:07:18 -07:00

tty_ldisc.c

tty: Use raw spin lock to protect TTY ldisc administration

2012-10-24 11:37:02 -07:00

tty_mutex.c

tty: tty_mutex.c: Fixed coding style warning (using printk)

2012-10-24 11:34:51 -07:00

tty_port.c

TTY: move tty buffers to tty_port

2012-10-22 16:58:28 -07:00