# Copyright (c) 2003 Marcel Moolenaar # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions # are met: # # 1. Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # 2. Redistributions in binary form must reproduce the above copyright # notice, this list of conditions and the following disclaimer in the # documentation and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR # IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES # OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. # IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, # INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT # NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # $FreeBSD$ #include #include #include #include #include #include #include # The UART hardware interface. The core UART code is hardware independent. # The details of the hardware are abstracted by the UART hardware interface. INTERFACE uart; # attach() - attach hardware. # This method is called when the device is being attached. All resources # have been allocated. The transmit and receive buffers exist, but no # high-level (ie tty) initialization has been done yet. # The intend of this method is to setup the hardware for normal operation. METHOD int attach { struct uart_softc *this; }; # detach() - detach hardware. # This method is called when a device is being detached from its bus. It # is the first action performed, so even the high-level (ie tty) interface # is still operational. # The intend of this method is to disable the hardware. METHOD int detach { struct uart_softc *this; }; # flush() - flush FIFOs. # This method is called to flush the transmitter and/or the receiver as # specified by the what argument. Characters are expected to be lost. METHOD int flush { struct uart_softc *this; int what; }; # getsig() - get line and modem signals. # This method retrieves the DTE and DCE signals and their corresponding # delta bits. The delta bits include those corresponding to DTE signals # when they were changed by a call to setsig. The delta bits maintained # by the hardware driver are cleared as a side-effect. A second call to # this function will not have any delta bits set, unless there was a # change in the signals in the mean time. METHOD int getsig { struct uart_softc *this; }; # ioctl() - get or set miscellaneous parameters. # This method is the bitbucket method. It can (and will) be used when there's # something we need to set or get for which a new method is overkill. It's # used for example to set HW or SW flow-control. METHOD int ioctl { struct uart_softc *this; int request; intptr_t data; }; # ipend() - query UART for pending interrupts. # When an interrupt is signalled, the handler will call this method to find # out which of the interrupt sources needs attention. The handler will use # this information to dispatch service routines that deal with each of the # interrupt sources. An advantage of this approach is that it allows multi- # port drivers (like puc(4)) to query multiple devices concurrently and # service them on an interrupt priority basis. If the hardware cannot provide # the information reliably, it is free to service the interrupt and return 0, # meaning that no attention is required. METHOD int ipend { struct uart_softc *this; } # param() - set communication parameters. # This method is called to change the communication parameters. METHOD int param { struct uart_softc *this; int baudrate; int databits; int stopbits; int parity; }; # probe() - detect hardware. # This method is called as part of the bus probe to make sure the # hardware exists. This function should also set the device description # to something that represents the hardware. METHOD int probe { struct uart_softc *this; }; # receive() - move data from the receive FIFO to the receive buffer. # This method is called to move received data to the receive buffer and # additionally should make sure the receive interrupt should be cleared. METHOD int receive { struct uart_softc *this; }; # setsig() - set line and modem signals. # This method allows changing DTE signals. The DTE delta bits indicate which # signals are to be changed and the DTE bits themselves indicate whether to # set or clear the signals. A subsequent call to getsig will return with the # DTE delta bits set of those DTE signals that did change by this method. METHOD int setsig { struct uart_softc *this; int sig; }; # transmit() - move data from the transmit buffer to the transmit FIFO. # This method is responsible for writing the Tx buffer to the UART and # additionally should make sure that a transmit interrupt is generated # when transmission is complete. METHOD int transmit { struct uart_softc *this; };