linux/drivers/tty, branch v3.4.22

Revert "serial: omap: fix software flow control"

2012-11-26T19:38:44Z

commit a4f743851f74fc3e0cc40c13082e65c24139f481 upstream. This reverts commit 957ee7270d632245b43f6feb0e70d9a5e9ea6cf6 (serial: omap: fix software flow control). As Russell has pointed out, that commit isn't fixing Software Flow Control at all, and it actually makes it even more broken. It was agreed to revert this commit and use Russell's latest UART patches instead. Signed-off-by: Felipe Balbi Cc: Russell King Acked-by: Tony Lindgren Cc: Andreas Bießmann Signed-off-by: Greg Kroah-Hartman

kdb,vt_console: Fix missed data due to pager overruns

2012-10-21T16:27:59Z

commit 17b572e82032bc246324ce136696656b66d4e3f1 upstream. It is possible to miss data when using the kdb pager. The kdb pager does not pay attention to the maximum column constraint of the screen or serial terminal. This result is not incrementing the shown lines correctly and the pager will print more lines that fit on the screen. Obviously that is less than useful when using a VGA console where you cannot scroll back. The pager will now look at the kdb_buffer string to see how many characters are printed. It might not be perfect considering you can output ASCII that might move the cursor position, but it is a substantially better approximation for viewing dmesg and trace logs. This also means that the vt screen needs to set the kdb COLUMNS variable. Signed-off-by: Jason Wessel Signed-off-by: Greg Kroah-Hartman

n_gsm: memory leak in uplink error path

2012-10-07T15:32:27Z

commit 88ed2a60610974443335c924d7cb8e5dcf9dbdc1 upstream. Uplink (TX) network data will go through gsm_dlci_data_output_framed there is a bug where if memory allocation fails, the skb which has already been pulled off the list will be lost. In addition TX skbs were being processed in LIFO order Fixed the memory leak, and changed to FIFO order processing Signed-off-by: Russ Gorby Tested-by: Kappel, LaurentX Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

n_gsm: added interlocking for gsm_data_lock for certain code paths

2012-10-07T15:32:27Z

commit 5e44708f75b0f8712da715d6babb0c21089b2317 upstream. There were some locking holes in the management of the MUX's message queue for 2 code paths: 1) gsmld_write_wakeup 2) receipt of CMD_FCON flow-control message In both cases gsm_data_kick is called w/o locking so it can collide with other other instances of gsm_data_kick (pulling messages tx_tail) or potentially other instances of __gsm_data_queu (adding messages to tx_head) Changed to take the tx_lock in these 2 cases Signed-off-by: Russ Gorby Tested-by: Yin, Fengwei Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

n_gsm: uplink SKBs accumulate on list

2012-10-07T15:32:27Z

commit 192b6041e75bb4a2aae73834037038cea139a92d upstream. gsm_dlci_data_kick will not call any output function if tx_bytes > THRESH_LO furthermore it will call the output function only once if tx_bytes == 0 If the size of the IP writes are on the order of THRESH_LO we can get into a situation where skbs accumulate on the outbound list being starved for events to call the output function. gsm_dlci_data_kick now calls the sweep function when tx_bytes==0 Signed-off-by: Russ Gorby Tested-by: Kappel, LaurentX Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

n_gsm.c: Implement 3GPP27.010 DLC start-up procedure in MUX

2012-10-07T15:32:27Z

commit 7e8ac7b23b67416700dfb8b4136a4e81ce675b48 upstream. In 3GPP27.010 5.8.1, it defined: The TE multiplexer initiates the establishment of the multiplexer control channel by sending a SABM frame on DLCI 0 using the procedures of clause 5.4.1. Once the multiplexer channel is established other DLCs may be established using the procedures of clause 5.4.1. This patch implement 5.8.1 in MUX level, it make sure DLC0 is the first channel to be setup. [or for those not familiar with the specification: it was possible to try and open a data connection while the control channel was not yet fully open, which is a spec violation and confuses some modems] Signed-off-by: xiaojin Tested-by: Yin, Fengwei [tweaked the order we check things and error code] Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

serial: set correct baud_base for EXSYS EX-41092 Dual 16950

2012-10-07T15:32:25Z

commit 26e8220adb0aec43b7acafa0f1431760eee28522 upstream. Apparently the same card model has two IDs, so this patch complements the commit 39aced68d664291db3324d0fcf0985ab5626aac2 adding the missing one. Signed-off-by: Flavio Leitner Signed-off-by: Greg Kroah-Hartman

serial: pl011: handle corruption at high clock speeds

2012-10-07T15:32:25Z

commit c5dd553b9fd069892c9e2de734f4f604e280fa7a upstream. This works around a few glitches in the ST version of the PL011 serial driver when using very high baud rates, as we do in the Ux500: 3, 3.25, 4 and 4.05 Mbps. Problem Observed/rootcause: When using high baud-rates, and the baudrate*8 is getting close to the provided clock frequency (so a division factor close to 1), when using bursts of characters (so they are abutted), then it seems as if there is not enough time to detect the beginning of the start-bit which is a timing reference for the entire character, and thus the sampling moment of character bits is moving towards the end of each bit, instead of the middle. Fix: Increase slightly the RX baud rate of the UART above the theoretical baudrate by 5%. This will definitely give more margin time to the UART_RX to correctly sample the data at the middle of the bit period. Also fix the ages old copy-paste error in the very stressed comment, it's referencing the registers used in the PL010 driver rather than the PL011 ones. Signed-off-by: Guillaume Jaunet Signed-off-by: Christophe Arnal Signed-off-by: Matthias Locher Signed-off-by: Rajanikanth HV Cc: Bibek Basu Cc: Par-Gunnar Hjalmdahl Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman

serial: omap: fix software flow control

2012-10-07T15:32:25Z

commit 957ee7270d632245b43f6feb0e70d9a5e9ea6cf6 upstream. Software flow control register bits were not defined correctly. Also clarify the IXON and IXOFF logic to reflect what userspace wants. Tested-by: Shubhrajyoti D Signed-off-by: Vikram Pandita Signed-off-by: Shubhrajyoti D Acked-by: Tony Lindgren Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman

Remove BUG_ON from n_tty_read()

2012-10-07T15:32:24Z

commit e9490e93c1978b6669f3e993caa3189be13ce459 upstream. Change the BUG_ON to WARN_ON and return in case of tty->read_buf==NULL. We want to track a couple of long standing reports of this but at the same time we can avoid killing the box. Signed-off-by: Stanislav Kozina Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman