linux/drivers/tty
Nicolas Pitre 95252f9c04 vcs: restore and document initial POLLPRI event
Restore and document the forced initial POLLPRI event reporting when
poll() is used for the first time. This used to be the implemented
behavior before recent changes. Because of the way poll() is implemented,
this prevents losing an event happening between the last read() and the
first poll() invocation.

Since poll() for /dev/vcs* was not always supported, user space probes
for its availability as follows:

	int fd = open("/dev/vcsa", O_RDONLY);
	struct pollfd p = { .fd = fd, .events = POLLPRI };
	available = (poll(&p, 1, 0) == 1);

Semantically, it makes sense to signal the first event as such even if
it might be spurious. The screen could be modified, and modified back
to its initial state before we get to read it, so users must be prepared
for that anyway.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-18 13:48:52 +01:00
..
hvc tty: Use of_node_name_{eq,prefix} for node name comparisons 2018-12-17 16:12:17 +01:00
ipwireless ipwireless: switch to ->[sg]et_serial() 2018-10-13 00:50:31 -04:00
serdev serdev: document the write functions using kernel-doc 2018-11-27 19:44:21 +01:00
serial tty: serial: lpc32xx_hs: fix missing console boot messages 2019-01-18 11:23:00 +01:00
vt vcs: restore and document initial POLLPRI event 2019-01-18 13:48:52 +01:00
amiserial.c kill TIOCSERGSTRUCT 2018-10-13 00:50:53 -04:00
cyclades.c cyclades: switch to ->[sg]et_serial() 2018-10-13 00:50:30 -04:00
ehv_bytechan.c tty: Convert to using %pOFn instead of device_node.name 2018-09-18 16:07:25 +02:00
goldfish.c headers: separate linux/mod_devicetable.h from linux/platform_device.h 2018-07-07 17:52:26 +02:00
isicom.c isicom: switch to ->[sg]et_serial() 2018-10-13 00:50:31 -04:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2018-04-09 09:04:10 -07:00
Makefile tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers 2018-03-26 15:57:24 +02:00
mips_ejtag_fdc.c
moxa.c moxa: switch to ->[sg]et_serial() 2018-10-13 00:50:32 -04:00
moxa.h
mxser.c mxser: switch to ->[sg]et_serial() 2018-10-13 00:50:32 -04:00
mxser.h
n_gsm.c n_gsm: Constify u8 and unsigned char usage 2019-01-18 12:57:40 +01:00
n_hdlc.c Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
n_null.c
n_r3964.c tty: Don't block on IO when ldisc change is pending 2018-12-05 12:16:33 +01:00
n_tracerouter.c
n_tracesink.c
n_tracesink.h
n_tty.c n_tty: update comment for WAKEUP_CHARS define 2019-01-18 13:25:11 +01:00
nozomi.c tty/nozomi: fix inconsistent indentation 2018-04-25 14:54:26 +02:00
pty.c pty: fix compat ioctls 2018-10-13 00:50:51 -04:00
rocket_int.h
rocket.c tty: rocket: Fix possible buffer overwrite on register_PCI 2018-08-02 10:11:32 +02:00
rocket.h
synclink_gt.c synclink_gt(): fix compat_ioctl() 2018-10-13 00:50:52 -04:00
synclink.c synclink: reduce pointless checks in ->ioctl() 2018-10-13 00:50:43 -04:00
synclinkmp.c synclink: reduce pointless checks in ->ioctl() 2018-10-13 00:50:43 -04:00
sysrq.c tty/sysrq: Do not call sync directly from sysrq_do_reset() 2018-12-05 12:02:12 +01:00
tty_audit.c audit: use current whenever possible 2018-11-26 18:41:21 -05:00
tty_baudrate.c termios, tty/tty_baudrate.c: fix buffer overrun 2018-11-08 03:36:45 -08:00
tty_buffer.c tty: wipe buffer. 2018-10-11 19:50:00 +02:00
tty_io.c tty: Don't hold ldisc lock in tty_reopen() if ldisc present 2019-01-11 17:03:42 +01:00
tty_ioctl.c move compat handling of tty ioctls to tty_compat_ioctl() 2018-09-14 11:12:17 -04:00
tty_jobctrl.c
tty_ldisc.c tty/ldsem: Add lockdep asserts for ldisc_sem 2018-12-05 12:16:33 +01:00
tty_ldsem.c tty/ldsem: Decrement wait_readers on timeouted down_read() 2018-12-05 12:16:33 +01:00
tty_mutex.c
tty_port.c tty: do not set TTY_IO_ERROR flag if console port 2018-11-27 09:58:11 +01:00
vcc.c