kernel/linux.git/drivers/tty, branch v3.0.6

TTY: pty, fix pty counting

2011-10-03T18:39:49+00:00

commit 24d406a6bf736f7aebdc8fa0f0ec86e0890c6d24 upstream. tty_operations->remove is normally called like: queue_release_one_tty ->tty_shutdown ->tty_driver_remove_tty ->tty_operations->remove However tty_shutdown() is called from queue_release_one_tty() only if tty_operations->shutdown is NULL. But for pty, it is not. pty_unix98_shutdown() is used there as ->shutdown. So tty_operations->remove of pty (i.e. pty_unix98_remove()) is never called. This results in invalid pty_count. I.e. what can be seen in /proc/sys/kernel/pty/nr. I see this was already reported at: https://lkml.org/lkml/2009/11/5/370 But it was not fixed since then. This patch is kind of a hackish way. The problem lies in ->install. We allocate there another tty (so-called tty->link). So ->install is called once, but ->remove twice, for both tty and tty->link. The fix here is to count both tty and tty->link and divide the count by 2 for user. And to have ->remove called, let's make tty_driver_remove_tty() global and call that from pty_unix98_shutdown() (tty_operations->shutdown). While at it, let's document that when ->shutdown is defined, tty_shutdown() is not called. Signed-off-by: Jiri Slaby Cc: Alan Cox Cc: "H. Peter Anvin" Signed-off-by: Greg Kroah-Hartman

tty: Add "spi:" prefix for spi modalias

2011-10-03T18:39:49+00:00

commit 8c4074cd2254606aeb788d518ccc27c9f97129e1 upstream. Since commit e0626e38 (spi: prefix modalias with "spi:"), the spi modalias is prefixed with "spi:". This patch adds "spi:" prefix and removes "-spi" suffix in the modalias. Signed-off-by: Axel Lin Signed-off-by: Greg Kroah-Hartman

8250: Fix race condition in serial8250_backup_timeout().

2011-10-03T18:39:48+00:00

commit dbb3b1ca5609d1f3848cd387d06cc60aaacf7f98 upstream. This is to fix an issue where output will suddenly become very slow. The problem occurs on 8250 UARTS with the hardware bug UART_BUG_THRE. BACKGROUND For normal UARTs (without UART_BUG_THRE): When the serial core layer gets new transmit data and the transmitter is idle, it buffers the data and calls the 8250s' serial8250_start_tx() routine which will simply enable the TX interrupt in the IER register and return. This should immediately fire a THRE interrupt and begin transmitting the data. For buggy UARTs (with UART_BUG_THRE): merely enabling the TX interrupt in IER does not necessarily generate a new THRE interrupt. Therefore, a background timer periodically checks to see if there is pending data, and starts transmission if that is the case. The bug happens on SMP systems when the system has nothing to transmit, the transmit interrupt is disabled and the following sequence occurs: - CPU0: The background timer routine serial8250_backup_timeout() starts and saves the state of the interrupt enable register (IER) and then disables all interrupts in IER. NOTE: The transmit interrupt (TI) bit is saved as disabled. - CPU1: The serial core gets data to transmit, grabs the port lock and calls serial8250_start_tx() which enables the TI in IER. - CPU0: serial8250_backup_timeout() waits for the port lock. - CPU1: finishes (with TI enabled) and releases the port lock. - CPU0: serial8250_backup_timeout() calls the interrupt routine which will transmit the next fifo's worth of data and then restores the IER from the previously saved value (TI disabled). At this point, as long as the serial core has more transmit data buffered, it will not call serial8250_start_tx() again and the background timer routine will slowly transmit the data. The fix is to have serial8250_start_tx() get the port lock before it saves the IER state and release it after restoring IER. This will prevent serial8250_start_tx() from running in parallel. Signed-off-by: Al Cooper Signed-off-by: Greg Kroah-Hartman

8250_pci: add support for Rosewill RC-305 4x serial port card

2011-10-03T18:39:48+00:00

commit 44178176ecc55ad370b837dd2c4b4b8bed1e3823 upstream. This patch adds support for the Rosewill RC-305 four-port PCI serial card, and probably any other four-port serial cards based on the Moschip MCS9865 chip, assuming that the EEPROM on the card was programmed in accordance with Table 6 of the MCS9865 EEPROM Application Note version 0.3 dated 16-May-2008, available from the Moschip web site (registration required). This patch is based on an earlier patch [1] for the SYBA 6x serial port card by Ira W. Snyder. [1]: http://www.gossamer-threads.com/lists/linux/kernel/1162435 Signed-off-by: Eric Smith Signed-off-by: Greg Kroah-Hartman

serial: 8250_pnp: add Intermec CV60 touchscreen device

2011-10-03T18:39:48+00:00

commit ab8ba3a2d2cba6a658ef596cd5b2e0905b6c8a9f upstream. It would have been nice if Intermec had supplied a PNP0501 _CID for the COM3 device, but they didn't, so we have to recognize it explicitly. Reference: https://bugzilla.kernel.org/show_bug.cgi?id=40612 CC: Jeff Chua Signed-off-by: Bjorn Helgaas Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

omap-serial: Allow IXON and IXOFF to be disabled.

2011-10-03T18:39:48+00:00

commit b280a97d1caf6fe1d38b51ebb31219391f5ad1a0 upstream. Fixes logic bug that software flow control cannot be disabled, because serial_omap_configure_xonxoff() is not called if both IXON and IXOFF bits are cleared. Signed-off-by: Nick Pelly Acked-by: Govindraj.R Tested-by: Govindraj.R Signed-off-by: Greg Kroah-Hartman

hvc_console: Improve tty/console put_chars handling

2011-08-05T04:58:41+00:00

commit 8c2381af0d3ef62a681dac5a141b6dabb27bf2e1 upstream. Currently, the hvc_console_print() function drops console output if the hvc backend's put_chars() returns 0. This patch changes this behavior to allow a retry through returning -EAGAIN. This change also affects the hvc_push() function. Both functions are changed to handle -EAGAIN and to retry the put_chars() operation. If a hvc backend returns -EAGAIN, the retry handling differs: - hvc_console_print() spins to write the complete console output. - hvc_push() behaves the same way as for returning 0. Now hvc backends can indirectly control the way how console output is handled through the hvc console layer. Signed-off-by: Hendrik Brueckner Acked-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Greg Kroah-Hartman

SERIAL: SC26xx: Fix link error.

2011-08-05T04:58:41+00:00

commit f2eb3cdf14457fccb14ae8c4d7d7cee088cd3957 upstream. Kconfig allows enabling console support for the SC26xx driver even when it's configured as a module resulting in a: ERROR: "uart_console_device" [drivers/tty/serial/sc26xx.ko] undefined! modpost error since the driver was merged in eea63e0e8a60d00485b47fb6e75d9aa2566b989b [SC26XX: New serial driver for SC2681 uarts] in 2.6.25. Fixed by only allowing console support to be enabled if the driver is builtin. Signed-off-by: Ralf Baechle Cc: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

tty/serial: Fix XSCALE serial ports, e.g. ce4100

2011-08-05T04:58:41+00:00

commit 5568181f188ae9485a0cdbea5ea48f63d186a298 upstream. Commit 4539c24fe4f92c09ee668ef959d3e8180df619b9 "tty/serial: Add explicit PORT_TEGRA type" introduced separate flags describing the need for IER bits UUE and RTOIE. Both bits are required for the XSCALE port type. While that patch updated uart_config[] as required, the auto-probing code wasn't updated to set the RTOIE flag when an XSCALE port type was detected. This caused such ports to stop working. This patch rectifies that. Reported-by: Sebastian Andrzej Siewior Tested-by: Sebastian Andrzej Siewior Signed-off-by: Stephen Warren Signed-off-by: Greg Kroah-Hartman

n_gsm: fix the wrong FCS handling

2011-08-05T04:58:40+00:00

commit f086ced17191fa0c5712539d2b680eae3dc972a1 upstream. FCS could be GSM0_SOF, so will break state machine... [This byte isn't quoted in any way so a SOF here doesn't imply an error occurred.] Signed-off-by: Alek Du Signed-off-by: Alan Cox [Trivial but best backported once its in 3.1rc I think] Signed-off-by: Greg Kroah-Hartman