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7 commits

Author SHA1 Message Date
Wolfram Sang
d3dec96e40 tty: serial: mpc5xxx: add support for mark/space parity
Tested on a custom MPC5200B-board using some fancy industrial protocol.
Verified that MPC512x has identical bits, so should work there as well.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-05 12:41:57 -07:00
Frank Benkert
e0955acecf mpc5200b/uart: select more tolerant uart prescaler on low baudrates
In addition to the /32 prescaler, the MPC5200B supports a second
baudrate prescaler /4 to reach higher baudrates.

The current calculation (introduced with commit 0d1f22e4) in the kernel
preferes this low prescaler as often as possible, but with some
imprecise counterparts the communication on low baudrates fails.

According a support-mail from freescale the low prescaler (/4) allows
just 1% tolerance in bittiming in contrast to 4% of the high prescaler
(/32).  The prescaler not only affects the baudrate-calculation, but
also the sampling of the bits on the wire.

With this patch, we use the slightly less precise, but higher tolerant
prescaler calculation on low baudrates up to (and including) 115200 baud
and the more precise calculation above.

Tested on a custom MPC5200B board with "fsl,mpc5200b-psc-uart".

Calculation Examples with prescaler (PS) 4 and 32 and divisor (DIV) on
various baudrates. Real stands for the real baudrate generated and Diff
for the differences between:
     50 Baud PS 32 DIV 0xa122 Real      50 Diff   0.00%
     75 Baud PS 32 DIV 0x6b6c Real      75 Diff   0.00%
    110 Baud PS 32 DIV 0x493e Real     110 Diff   0.00%
    134 Baud PS 32 DIV 0x3c20 Real     133 Diff   0.75%
    150 Baud PS 32 DIV 0x35b6 Real     150 Diff   0.00%
    200 Baud PS 32 DIV 0x2849 Real     199 Diff   0.50%
    300 Baud PS  4 DIV 0xd6d8 Real     300 Diff   0.00%
             PS 32 DIV 0x1adb Real     300 Diff   0.00%
    600 Baud PS  4 DIV 0x6b6c Real     600 Diff   0.00%
             PS 32 DIV 0x0d6e Real     599 Diff   0.17%
   1200 Baud PS  4 DIV 0x35b6 Real    1200 Diff   0.00%
             PS 32 DIV 0x06b7 Real    1199 Diff   0.08%
   1800 Baud PS  4 DIV 0x23cf Real    1799 Diff   0.06%
             PS 32 DIV 0x047a Real    1799 Diff   0.06%
   2400 Baud PS  4 DIV 0x1adb Real    2400 Diff   0.00%
             PS 32 DIV 0x035b Real    2401 Diff - 0.04%
   4800 Baud PS  4 DIV 0x0d6e Real    4799 Diff   0.02%
             PS 32 DIV 0x01ae Real    4796 Diff   0.08%
   9600 Baud PS  4 DIV 0x06b7 Real    9598 Diff   0.02%
             PS 32 DIV 0x00d7 Real    9593 Diff   0.07%
  19200 Baud PS  4 DIV 0x035b Real   19208 Diff - 0.04%
             PS 32 DIV 0x006b Real   19275 Diff - 0.39%
  38400 Baud PS  4 DIV 0x01ae Real   38372 Diff   0.07%
             PS 32 DIV 0x0036 Real   38194 Diff   0.54%
  57600 Baud PS  4 DIV 0x011e Real   57692 Diff - 0.16%
             PS 32 DIV 0x0024 Real   57291 Diff   0.54%
  76800 Baud PS  4 DIV 0x00d7 Real   76744 Diff   0.07%
             PS 32 DIV 0x001b Real   76388 Diff   0.54%
 115200 Baud PS  4 DIV 0x008f Real  115384 Diff - 0.16%
             PS 32 DIV 0x0012 Real  114583 Diff   0.54%
 153600 Baud PS  4 DIV 0x006b Real  154205 Diff - 0.39%
             PS 32 DIV 0x000d Real  158653 Diff - 3.29%
 230400 Baud PS  4 DIV 0x0048 Real  229166 Diff   0.54%
             PS 32 DIV 0x0009 Real  229166 Diff   0.54%
 307200 Baud PS  4 DIV 0x0036 Real  305555 Diff   0.54%
             PS 32 DIV 0x0007 Real  294642 Diff   4.09%
 460800 Baud PS  4 DIV 0x0024 Real  458333 Diff   0.54%
             PS 32 DIV 0x0005 Real  412500 Diff  10.48%
 500000 Baud PS  4 DIV 0x0021 Real  500000 Diff   0.00%
             PS 32 DIV 0x0004 Real  515625 Diff - 3.13%
 576000 Baud PS  4 DIV 0x001d Real  568965 Diff   1.22%
             PS 32 DIV 0x0004 Real  515625 Diff  10.48%
 614400 Baud PS  4 DIV 0x001b Real  611111 Diff   0.54%
             PS 32 DIV 0x0003 Real  687500 Diff -11.90%
 921600 Baud PS  4 DIV 0x0012 Real  916666 Diff   0.54%
             PS 32 DIV 0x0002 Real 1031250 Diff -11.90%
1000000 Baud PS  4 DIV 0x0011 Real  970588 Diff   2.94%
             PS 32 DIV 0x0002 Real 1031250 Diff - 3.13%
1152000 Baud PS  4 DIV 0x000e Real 1178571 Diff - 2.31%
             PS 32 DIV 0x0002 Real 1031250 Diff  10.48%
1500000 Baud PS  4 DIV 0x000b Real 1500000 Diff   0.00%
             PS 32 DIV 0x0001 Real 2062500 Diff -37.50%
2000000 Baud PS  4 DIV 0x0008 Real 2062500 Diff - 3.13%
             PS 32 DIV 0x0001 Real 2062500 Diff - 3.13%
2500000 Baud PS  4 DIV 0x0007 Real 2357142 Diff   5.71%
             PS 32 DIV 0x0001 Real 2062500 Diff  17.50%
3000000 Baud PS  4 DIV 0x0006 Real 2750000 Diff   8.33%
             PS 32 DIV 0x0001 Real 2062500 Diff  31.25%
3500000 Baud PS  4 DIV 0x0005 Real 3300000 Diff   5.71%
             PS 32 DIV 0x0001 Real 2062500 Diff  41.07%
4000000 Baud PS  4 DIV 0x0004 Real 4125000 Diff - 3.13%
             PS 32 DIV 0x0001 Real 2062500 Diff  48.44%

Signed-off-by: Frank Benkert <frank.benkert@avat.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-08 13:15:50 -08:00
Alan Cox
d4e33fac24 serial: Kill off NO_IRQ
We transform the offenders into a test of irq <= 0 which will be ok while
the ARM people get their platform sorted. Once that is done (or in a while
if they don't do it anyway) then we will change them all to !irq checks.

For arch specific drivers that are already using NO_IRQ = 0 we just test
against zero so we don't need to re-review them later.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2012-01-26 17:14:50 -08:00
Yong Zhang
9cfb5c05fe TTY: irq: Remove IRQF_DISABLED
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-22 16:08:57 -07:00
Jiri Slaby
ee160a38ee TTY: serial, fix includes in some drivers
linux/tty_flip.h is included in linux/serial_core.h. But this may (and
will) change in the future. Then we would get build errors such as:
.../tty/serial/max3107.c: In function ‘put_data_to_circ_buf’:
.../tty/serial/max3107.c:149:2: error: implicit declaration of function ‘tty_insert_flip_string’

So fix all the drviers which call tty flip buffer helpers to really
include linux/tty_flip.h. And also make sure that those include
linux/tty.h when operating with struct tty_struct.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-09-22 15:49:26 -07:00
Grant Likely
793218dfea dt/serial: Eliminate users of of_platform_{,un}register_driver
Get rid of users of of_platform_driver in drivers/serial.  The
of_platform_{,un}register_driver functions are going away, so the
users need to be converted to using the platform_bus_type directly.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
2011-02-28 13:22:46 -07:00
Greg Kroah-Hartman
ab4382d274 tty: move drivers/serial/ to drivers/tty/serial/
The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.

This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-13 12:10:18 -08:00
Renamed from drivers/serial/mpc52xx_uart.c (Browse further)