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/tty<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/close_delay 87Date: October 2012 88Contact: Alan Cox <alan@linux.intel.com> 89Description: 90 Show the closing delay time for this port in centiseconds. 91 92 These sysfs values expose the TIOCGSERIAL interface via 93 sysfs rather than via ioctls. 94 95What: /sys/class/tty/ttyS<x>/closing_wait 96Date: October 2012 97Contact: Alan Cox <alan@linux.intel.com> 98Description: 99 Show the close wait time for this port in centiseconds. 100 101 Waiting forever is represented as 0. If waiting on close is 102 disabled then the value is 65535. 103 104 These sysfs values expose the TIOCGSERIAL interface via 105 sysfs rather than via ioctls. 106 107What: /sys/class/tty/ttyS<x>/custom_divisor 108Date: October 2012 109Contact: Alan Cox <alan@linux.intel.com> 110Description: 111 Show the custom divisor if any that is set on this port. 112 113 These sysfs values expose the TIOCGSERIAL interface via 114 sysfs rather than via ioctls. 115 116What: /sys/class/tty/ttyS<x>/io_type 117Date: October 2012 118Contact: Alan Cox <alan@linux.intel.com> 119Description: 120 Show the I/O type that is to be used with the iomem base 121 address. 122 123 These sysfs values expose the TIOCGSERIAL interface via 124 sysfs rather than via ioctls. 125 126What: /sys/class/tty/ttyS<x>/iomem_base 127Date: October 2012 128Contact: Alan Cox <alan@linux.intel.com> 129Description: 130 The I/O memory base for this port. 131 132 These sysfs values expose the TIOCGSERIAL interface via 133 sysfs rather than via ioctls. 134 135What: /sys/class/tty/ttyS<x>/iomem_reg_shift 136Date: October 2012 137Contact: Alan Cox <alan@linux.intel.com> 138Description: 139 Show the register shift indicating the spacing to be used 140 for accesses on this iomem address. 141 142 These sysfs values expose the TIOCGSERIAL interface via 143 sysfs rather than via ioctls. 144 145What: /sys/class/tty/ttyS<x>/rx_trig_bytes 146Date: May 2014 147Contact: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> 148Description: 149 Shows current RX interrupt trigger bytes or sets the 150 user specified value to change it for the FIFO buffer. 151 Users can show or set this value regardless of opening the 152 serial device file or not. 153 154 The RX trigger can be set one of four kinds of values for UART 155 serials. When users input a meaning less value to this I/F, 156 the RX trigger is changed to the nearest lower value for the 157 device specification. For example, when user sets 7bytes on 158 16550A, which has 1/4/8/14 bytes trigger, the RX trigger is 159 automatically changed to 4 bytes. 160 161What: /sys/class/tty/ttyS<x>/console 162Date: February 2020 163Contact: Andy Shevchenko <andriy.shevchenko@linux.intel.com> 164Description: 165 Allows user to detach or attach back the given device as 166 kernel console. It shows and accepts a boolean variable. 167