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authorMarius Strobl <marius@FreeBSD.org>2016-01-19 23:34:27 +0000
committerMarius Strobl <marius@FreeBSD.org>2016-01-19 23:34:27 +0000
commit9750d9e5b6f011a99da26a6f1e57c65545d26473 (patch)
tree317f9c0bd52607efdfd2f6c62f25b5b2aa3842e2 /sys/sys/ttydevsw.h
parenteb2ad8724bbaa87ab9a264562075d28e5428e9c2 (diff)
downloadsrc-9750d9e5b6f011a99da26a6f1e57c65545d26473.tar.gz
src-9750d9e5b6f011a99da26a6f1e57c65545d26473.zip
Fix tty_drain() and, thus, TIOCDRAIN of the current tty(4) incarnation
to actually wait until the TX FIFOs of UARTs have be drained before returning. This is done by bringing the equivalent of the TS_BUSY flag found in the previous implementation back in an ABI-preserving way. Reported and tested by: Patrick Powell Most likely, drivers for USB-serial-adapters likewise incorporating TX FIFOs as well as other terminal devices that buffer output in some form should also provide implementations of tsw_busy. MFC after: 3 days
Notes
Notes: svn path=/head/; revision=294362
Diffstat (limited to 'sys/sys/ttydevsw.h')
-rw-r--r--sys/sys/ttydevsw.h14
1 files changed, 13 insertions, 1 deletions
diff --git a/sys/sys/ttydevsw.h b/sys/sys/ttydevsw.h
index 748ae0bee8e1..ae70613523a1 100644
--- a/sys/sys/ttydevsw.h
+++ b/sys/sys/ttydevsw.h
@@ -54,6 +54,7 @@ typedef int tsw_mmap_t(struct tty *tp, vm_ooffset_t offset,
vm_paddr_t * paddr, int nprot, vm_memattr_t *memattr);
typedef void tsw_pktnotify_t(struct tty *tp, char event);
typedef void tsw_free_t(void *softc);
+typedef bool tsw_busy_t(struct tty *tp);
struct ttydevsw {
unsigned int tsw_flags; /* Default TTY flags. */
@@ -74,7 +75,9 @@ struct ttydevsw {
tsw_free_t *tsw_free; /* Destructor. */
- void *tsw_spare[4]; /* For future use. */
+ tsw_busy_t *tsw_busy; /* Draining output. */
+
+ void *tsw_spare[3]; /* For future use. */
};
static __inline int
@@ -181,4 +184,13 @@ ttydevsw_free(struct tty *tp)
tp->t_devsw->tsw_free(tty_softc(tp));
}
+static __inline bool
+ttydevsw_busy(struct tty *tp)
+{
+
+ MPASS(tty_gone(tp));
+
+ return (tp->t_devsw->tsw_busy(tp));
+}
+
#endif /* !_SYS_TTYDEVSW_H_ */