1What:		/sys/class/tty/console/active
2Date:		Nov 2010
3Contact:	Kay Sievers <kay.sievers@vrfy.org>
4Description:
5		 Shows the list of currently configured
6		 console devices, like 'tty1 ttyS0'.
7		 The last entry in the file is the active
8		 device connected to /dev/console.
9		 The file supports poll() to detect virtual
10		 console switches.
11
12What:		/sys/class/tty/tty0/active
13Date:		Nov 2010
14Contact:	Kay Sievers <kay.sievers@vrfy.org>
15Description:
16		 Shows the currently active virtual console
17		 device, like 'tty1'.
18		 The file supports poll() to detect virtual
19		 console switches.
20
21What:		/sys/class/tty/ttyS0/uartclk
22Date:		Sep 2012
23Contact:	Tomas Hlavacek <tmshlvck@gmail.com>
24Description:
25		 Shows the current uartclk value associated with the
26		 UART port in serial_core, that is bound to TTY like ttyS0.
27		 uartclk = 16 * baud_base
28
29		 These sysfs values expose the TIOCGSERIAL interface via
30		 sysfs rather than via ioctls.
31
32What:		/sys/class/tty/ttyS0/type
33Date:		October 2012
34Contact:	Alan Cox <alan@linux.intel.com>
35Description:
36		 Shows the current tty type for this port.
37
38		 These sysfs values expose the TIOCGSERIAL interface via
39		 sysfs rather than via ioctls.
40
41What:		/sys/class/tty/ttyS0/line
42Date:		October 2012
43Contact:	Alan Cox <alan@linux.intel.com>
44Description:
45		 Shows the current tty line number for this port.
46
47		 These sysfs values expose the TIOCGSERIAL interface via
48		 sysfs rather than via ioctls.
49
50What:		/sys/class/tty/ttyS0/port
51Date:		October 2012
52Contact:	Alan Cox <alan@linux.intel.com>
53Description:
54		 Shows the current tty port I/O address for this port.
55
56		 These sysfs values expose the TIOCGSERIAL interface via
57		 sysfs rather than via ioctls.
58
59What:		/sys/class/tty/ttyS0/irq
60Date:		October 2012
61Contact:	Alan Cox <alan@linux.intel.com>
62Description:
63		 Shows the current primary interrupt for this port.
64
65		 These sysfs values expose the TIOCGSERIAL interface via
66		 sysfs rather than via ioctls.
67
68What:		/sys/class/tty/ttyS0/flags
69Date:		October 2012
70Contact:	Alan Cox <alan@linux.intel.com>
71Description:
72		 Show the tty port status flags for this port.
73
74		 These sysfs values expose the TIOCGSERIAL interface via
75		 sysfs rather than via ioctls.
76
77What:		/sys/class/tty/ttyS0/xmit_fifo_size
78Date:		October 2012
79Contact:	Alan Cox <alan@linux.intel.com>
80Description:
81		 Show the transmit FIFO size for this port.
82
83		 These sysfs values expose the TIOCGSERIAL interface via
84		 sysfs rather than via ioctls.
85
86What:		/sys/class/tty/ttyS0/close_delay
87Date:		October 2012
88Contact:	Alan Cox <alan@linux.intel.com>
89Description:
90		 Show the closing delay time for this port in ms.
91
92		 These sysfs values expose the TIOCGSERIAL interface via
93		 sysfs rather than via ioctls.
94
95What:		/sys/class/tty/ttyS0/closing_wait
96Date:		October 2012
97Contact:	Alan Cox <alan@linux.intel.com>
98Description:
99		 Show the close wait time for this port in ms.
100
101		 These sysfs values expose the TIOCGSERIAL interface via
102		 sysfs rather than via ioctls.
103
104What:		/sys/class/tty/ttyS0/custom_divisor
105Date:		October 2012
106Contact:	Alan Cox <alan@linux.intel.com>
107Description:
108		 Show the custom divisor if any that is set on this port.
109
110		 These sysfs values expose the TIOCGSERIAL interface via
111		 sysfs rather than via ioctls.
112
113What:		/sys/class/tty/ttyS0/io_type
114Date:		October 2012
115Contact:	Alan Cox <alan@linux.intel.com>
116Description:
117		 Show the I/O type that is to be used with the iomem base
118		 address.
119
120		 These sysfs values expose the TIOCGSERIAL interface via
121		 sysfs rather than via ioctls.
122
123What:		/sys/class/tty/ttyS0/iomem_base
124Date:		October 2012
125Contact:	Alan Cox <alan@linux.intel.com>
126Description:
127		 The I/O memory base for this port.
128
129		 These sysfs values expose the TIOCGSERIAL interface via
130		 sysfs rather than via ioctls.
131
132What:		/sys/class/tty/ttyS0/iomem_reg_shift
133Date:		October 2012
134Contact:	Alan Cox <alan@linux.intel.com>
135Description:
136		 Show the register shift indicating the spacing to be used
137		 for accesses on this iomem address.
138
139		 These sysfs values expose the TIOCGSERIAL interface via
140		 sysfs rather than via ioctls.
141
142What:		/sys/class/tty/ttyS0/rx_trig_bytes
143Date:		May 2014
144Contact:	Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
145Description:
146		 Shows current RX interrupt trigger bytes or sets the
147		 user specified value to change it for the FIFO buffer.
148		 Users can show or set this value regardless of opening the
149		 serial device file or not.
150
151		 The RX trigger can be set one of four kinds of values for UART
152		 serials. When users input a meaning less value to this I/F,
153		 the RX trigger is changed to the nearest lower value for the
154		 device specification. For example, when user sets 7bytes on
155		 16550A, which has 1/4/8/14 bytes trigger, the RX trigger is
156		 automatically changed to 4 bytes.
157