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  1. 07 4月, 2009 22 次提交
  3. 06 4月, 2009 2 次提交
  5. 02 4月, 2009 1 次提交
  7. 01 4月, 2009 2 次提交
  9. 30 3月, 2009 1 次提交
  11. 25 3月, 2009 2 次提交
  13. 24 3月, 2009 1 次提交
  15. 23 3月, 2009 1 次提交
  17. 13 3月, 2009 1 次提交
  19. 10 3月, 2009 1 次提交
  21. 09 3月, 2009 1 次提交
  23. 03 3月, 2009 1 次提交
  25. 27 2月, 2009 1 次提交
  27. 21 2月, 2009 1 次提交
    • M
      8250: fix boot hang with serial console when using with Serial Over Lan port · b6adea33
      由 Mauro Carvalho Chehab 提交于 
      Intel 8257x Ethernet boards have a feature called Serial Over Lan.

This feature works by emulating a serial port, and it is detected by
kernel as a normal 8250 port.  However, this emulation is not perfect, as
also noticed on changeset 7500b1f6.

Before this patch, the kernel were trying to check if the serial TX is
capable of work using IRQ's.

This were done with a code similar this:

        serial_outp(up, UART_IER, UART_IER_THRI);
        lsr = serial_in(up, UART_LSR);
        iir = serial_in(up, UART_IIR);
        serial_outp(up, UART_IER, 0);

        if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT)
		up->bugs |= UART_BUG_TXEN;

This works fine for other 8250 ports, but, on 8250-emulated SoL port, the
chip is a little lazy to down UART_IIR_NO_INT at UART_IIR register.

Due to that, UART_BUG_TXEN is sometimes enabled.  However, as TX IRQ keeps
working, and the TX polling is now enabled, the driver miss-interprets the
IRQ received later, hanging up the machine until a key is pressed at the
serial console.

This is the 6 version of this patch.  Previous versions were trying to
introduce a large enough delay between serial_outp and serial_in(up,
UART_IIR), but not taking forever.  However, the needed delay couldn't be
safely determined.

At the experimental tests, a delay of 1us solves most of the cases, but
still hangs sometimes.  Increasing the delay to 5us was better, but still
doesn't solve.  A very high delay of 50 ms seemed to work every time.

However, poking around with delays and pray for it to be enough doesn't
seem to be a good approach, even for a quirk.

So, instead of playing with random large arbitrary delays, let's just
disable UART_BUG_TXEN for all SoL ports.

[akpm@linux-foundation.org: fix warnings]
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b6adea33
  29. 19 2月, 2009 2 次提交
    • A
      jsm: additional device support · ffa7525c
      由 Adam Lackorzynski 提交于 
      I have a Digi Neo 8 PCI card (114f:00b1) Serial controller: Digi
International Digi Neo 8 (rev 05)

that works with the jsm driver after using the following patch.
Signed-off-by: NAdam Lackorzynski <adam@os.inf.tu-dresden.de>
Cc: Scott H Kilau <Scott_Kilau@digi.com>
Cc: Wendy Xiong <wendyx@us.ibm.com>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ffa7525c
    • A
      atmel_serial might lose modem status change · 27c0c8e5
      由 Atsushi Nemoto 提交于 
      I found a problem of handling of modem status of atmel_serial driver.

With the commit 1ecc26 ("atmel_serial: split the interrupt handler"),
handling of modem status signal was splitted into two parts.  The
atmel_tasklet_func() compares new status with irq_status_prev, but
irq_status_prev is not correct if signal status was changed while the port
is closed.

Here is a sequence to cause problem:

1. Remote side sets CTS (and DSR).
2. Local side close the port.
3. Local side clears RTS and DTR.
4. Remote side clears CTS and DSR.
5. Local side reopen the port.  hw_stopped becomes 1.
6. Local side sets RTS and DTR.
7. Remote side sets CTS and DSR.

Then CTS change interrupt can be received, but since CTS bit in
irq_status_prev and new status is same, uart_handle_cts_change() will not
be called (so hw_stopped will not be cleared, i.e.  cannot send any data).

I suppose irq_status_prev should be initialized at somewhere in open
sequence.

Itai Levi pointed out that we need to initialize atmel_port->irq_status
as well here. His analysis is as follows:

> Regarding the second part of the patch (which resets irq_status_prev),
> it turns out that both versions of the patch (mine and Atsushi's)
> still leave enough room for faulty behavior when opening the port.
>
> This is because we are not resetting both irq_status_prev and
> irq_status in atmel_startup() to CSR, which leads faulty behavior in
> the following sequences:
>
> First case:
> 1. closing the port while CTS line = 1 (TX not allowed)
> 2. setting CTS line = 0 (TX allowed)
> 3. opening the port
> 4. transmitting one char
> 5. Cannot transmit more chars, although CTS line is 0
>
> Second case:
> 1. closing the port while CTS line = 0 (TX allowed)
> 2. setting CTS line = 1 (TX not allowed)
> 3. opening the port
> 4. receiving some chars
> 5. Now we can transmit, although CTS line is 1
>
> This reason for this is that the tasklet is scheduled as a result of
> TX or RX interrupts (not a status change!), in steps 4 above. Inside
> the tasklet, the atmel_port->irq_status (which holds the value from
> the previous session) is compared to atmel_port->irq_status_prev.
> Hence, a status-change of the CTS line is faultily detected.
>
> Both cases were verified on 9260 hardware.

[haavard.skinnemoen@atmel.com: folded with patch from Itai Levi]
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NHaavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Remy Bohmer <linux@bohmer.net>
Cc: Marc Pignat <marc.pignat@hevs.ch>
Cc: Itai Levi <itai.levi.devel@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      27c0c8e5