linux/drivers/tty
Jorge Ramirez-Ortiz 1c9be31015 drivers/tty: amba: defer DMA probe until the DMA channel is required.
Fix a race condition that happens when device_initcall(pl011_dma_initicall)
is executed before all the devices have been probed - this issue was observed on
a hisi_6220 SoC (HiKey board from Linaro).

The deferred driver probing framework relies on late_initcall to trigger
deferred probes so it is just possible that, even with a valid DMA driver ready
to be loaded, we fail to synchronize with it.

The proposed implementation delays probing the DMA until dma_startup.

As this is invoked on port startup and port resume - but DMA probing is only
required once - we avoid calling multiple times using a new field in
uart_amba_port to track this scenario.

This commit allows for subsequent attempts to associate an external DMA if the
DMA driver itself is not available (but present in the deferred probe pending
list).

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07 03:50:30 +01:00
..
hvc s390/hvc_iucv: add simple wildcard matches to the iucv allow filter 2015-01-22 12:16:56 +01:00
ipwireless tty: ipwireless: Fix probable mask then right shift defects 2014-11-05 20:06:33 -08:00
serial drivers/tty: amba: defer DMA probe until the DMA channel is required. 2015-03-07 03:50:30 +01:00
vt vt: provide notifications on selection changes 2015-02-02 10:09:54 -08:00
amiserial.c TTY: fix misspelling of current function in string 2015-01-09 14:38:15 -08:00
bfin_jtag_comm.c
cyclades.c
ehv_bytechan.c tty: remove unused variable sprop 2015-02-03 15:52:13 -08:00
goldfish.c
isicom.c tty/isicom: fix big-endian compile warning 2015-02-02 10:11:25 -08:00
Kconfig
Makefile
metag_da.c
moxa.c
moxa.h
mxser.c
mxser.h
n_gsm.c
n_hdlc.c
n_r3964.c
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c n_tty: Fix signal handling flushes 2015-02-02 10:11:27 -08:00
nozomi.c
pty.c n_tty: Fix signal handling flushes 2015-02-02 10:11:27 -08:00
rocket_int.h
rocket.c TTY: fix misspelling of current function in string 2015-01-09 14:38:15 -08:00
rocket.h
synclink_gt.c
synclink.c
synclinkmp.c
sysrq.c oom, PM: make OOM detection in the freezer path raceless 2015-02-11 17:06:03 -08:00
tty_audit.c
tty_buffer.c pty: Fix buffer flush deadlock 2015-02-02 10:11:27 -08:00
tty_io.c tty: Prevent hw state corruption in exclusive mode reopen 2015-01-09 13:46:02 -08:00
tty_ioctl.c tty: Remove external interface for tty_set_termios() 2015-02-02 10:11:28 -08:00
tty_ldisc.c tty: Allow safe access to termios for set_ldisc() handlers 2014-11-06 14:57:27 -08:00
tty_ldsem.c
tty_mutex.c tty: Make lock subclasses available for other tty locks 2015-02-02 10:11:27 -08:00
tty_port.c tty: Deletion of unnecessary checks before two function calls 2014-11-26 19:35:49 -08:00