Documentation/ABI/testing/sysfs-tty

   1 What:           /sys/class/tty/console/active
   2 Date:           Nov 2010
   3 Contact:        Kay Sievers <kay.sievers@vrfy.org>
   4 Description:
   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
  12 What:           /sys/class/tty/tty0/active
  13 Date:           Nov 2010
  14 Contact:        Kay Sievers <kay.sievers@vrfy.org>
  15 Description:
  16                  Shows the currently active virtual console
  17                  device, like 'tty1'.
  18                  The file supports poll() to detect virtual
  19                  console switches.
  20
  21 What:           /sys/class/tty/ttyS0/uartclk
  22 Date:           Sep 2012
  23 Contact:        Tomas Hlavacek <tmshlvck@gmail.com>
  24 Description:
  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
  32 What:           /sys/class/tty/ttyS0/type
  33 Date:           October 2012
  34 Contact:        Alan Cox <alan@linux.intel.com>
  35 Description:
  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
  41 What:           /sys/class/tty/ttyS0/line
  42 Date:           October 2012
  43 Contact:        Alan Cox <alan@linux.intel.com>
  44 Description:
  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
  50 What:           /sys/class/tty/ttyS0/port
  51 Date:           October 2012
  52 Contact:        Alan Cox <alan@linux.intel.com>
  53 Description:
  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
  59 What:           /sys/class/tty/ttyS0/irq
  60 Date:           October 2012
  61 Contact:        Alan Cox <alan@linux.intel.com>
  62 Description:
  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
  68 What:           /sys/class/tty/ttyS0/flags
  69 Date:           October 2012
  70 Contact:        Alan Cox <alan@linux.intel.com>
  71 Description:
  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
  77 What:           /sys/class/tty/ttyS0/xmit_fifo_size
  78 Date:           October 2012
  79 Contact:        Alan Cox <alan@linux.intel.com>
  80 Description:
  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
  86 What:           /sys/class/tty/ttyS0/close_delay
  87 Date:           October 2012
  88 Contact:        Alan Cox <alan@linux.intel.com>
  89 Description:
  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
  95 What:           /sys/class/tty/ttyS0/closing_wait
  96 Date:           October 2012
  97 Contact:        Alan Cox <alan@linux.intel.com>
  98 Description:
  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
 104 What:           /sys/class/tty/ttyS0/custom_divisor
 105 Date:           October 2012
 106 Contact:        Alan Cox <alan@linux.intel.com>
 107 Description:
 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
 113 What:           /sys/class/tty/ttyS0/io_type
 114 Date:           October 2012
 115 Contact:        Alan Cox <alan@linux.intel.com>
 116 Description:
 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
 123 What:           /sys/class/tty/ttyS0/iomem_base
 124 Date:           October 2012
 125 Contact:        Alan Cox <alan@linux.intel.com>
 126 Description:
 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
 132 What:           /sys/class/tty/ttyS0/iomem_reg_shift
 133 Date:           October 2012
 134 Contact:        Alan Cox <alan@linux.intel.com>
 135 Description:
 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
 142 What:           /sys/class/tty/ttyS0/rx_trig_bytes
 143 Date:           May 2014
 144 Contact:        Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
 145 Description:
 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.