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 ms. 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 ms. 100 101 These sysfs values expose the TIOCGSERIAL interface via 102 sysfs rather than via ioctls. 103 104What: /sys/class/tty/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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/ttyS<x>/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 158What: /sys/class/tty/ttyS<x>/console 159Date: February 2020 160Contact: Andy Shevchenko <andriy.shevchenko@linux.intel.com> 161Description: 162 Allows user to detach or attach back the given device as 163 kernel console. It shows and accepts a boolean variable. 164