struct device;
struct gpio_desc;
-/*
+/**
+ * struct uart_ops -- interface between serial_core and the driver
+ *
* This structure describes all the operations that can be done on the
- * physical hardware. See Documentation/driver-api/serial/driver.rst for details.
+ * physical hardware.
+ *
+ * @tx_empty: ``unsigned int ()(struct uart_port *port)``
+ *
+ * This function tests whether the transmitter fifo and shifter for the
+ * @port is empty. If it is empty, this function should return
+ * %TIOCSER_TEMT, otherwise return 0. If the port does not support this
+ * operation, then it should return %TIOCSER_TEMT.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ * This call must not sleep
+ *
+ * @set_mctrl: ``void ()(struct uart_port *port, unsigned int mctrl)``
+ *
+ * This function sets the modem control lines for @port to the state
+ * described by @mctrl. The relevant bits of @mctrl are:
+ *
+ * - %TIOCM_RTS RTS signal.
+ * - %TIOCM_DTR DTR signal.
+ * - %TIOCM_OUT1 OUT1 signal.
+ * - %TIOCM_OUT2 OUT2 signal.
+ * - %TIOCM_LOOP Set the port into loopback mode.
+ *
+ * If the appropriate bit is set, the signal should be driven
+ * active. If the bit is clear, the signal should be driven
+ * inactive.
+ *
+ * Locking: @port->lock taken.
+ * Interrupts: locally disabled.
+ * This call must not sleep
+ *
+ * @get_mctrl: ``unsigned int ()(struct uart_port *port)``
+ *
+ * Returns the current state of modem control inputs of @port. The state
+ * of the outputs should not be returned, since the core keeps track of
+ * their state. The state information should include:
+ *
+ * - %TIOCM_CAR state of DCD signal
+ * - %TIOCM_CTS state of CTS signal
+ * - %TIOCM_DSR state of DSR signal
+ * - %TIOCM_RI state of RI signal
+ *
+ * The bit is set if the signal is currently driven active. If
+ * the port does not support CTS, DCD or DSR, the driver should
+ * indicate that the signal is permanently active. If RI is
+ * not available, the signal should not be indicated as active.
+ *
+ * Locking: @port->lock taken.
+ * Interrupts: locally disabled.
+ * This call must not sleep
+ *
+ * @stop_tx: ``void ()(struct uart_port *port)``
+ *
+ * Stop transmitting characters. This might be due to the CTS line
+ * becoming inactive or the tty layer indicating we want to stop
+ * transmission due to an %XOFF character.
+ *
+ * The driver should stop transmitting characters as soon as possible.
+ *
+ * Locking: @port->lock taken.
+ * Interrupts: locally disabled.
+ * This call must not sleep
+ *
+ * @start_tx: ``void ()(struct uart_port *port)``
+ *
+ * Start transmitting characters.
+ *
+ * Locking: @port->lock taken.
+ * Interrupts: locally disabled.
+ * This call must not sleep
+ *
+ * @throttle: ``void ()(struct uart_port *port)``
+ *
+ * Notify the serial driver that input buffers for the line discipline are
+ * close to full, and it should somehow signal that no more characters
+ * should be sent to the serial port.
+ * This will be called only if hardware assisted flow control is enabled.
+ *
+ * Locking: serialized with @unthrottle() and termios modification by the
+ * tty layer.
+ *
+ * @unthrottle: ``void ()(struct uart_port *port)``
+ *
+ * Notify the serial driver that characters can now be sent to the serial
+ * port without fear of overrunning the input buffers of the line
+ * disciplines.
+ *
+ * This will be called only if hardware assisted flow control is enabled.
+ *
+ * Locking: serialized with @throttle() and termios modification by the
+ * tty layer.
+ *
+ * @send_xchar: ``void ()(struct uart_port *port, char ch)``
+ *
+ * Transmit a high priority character, even if the port is stopped. This
+ * is used to implement XON/XOFF flow control and tcflow(). If the serial
+ * driver does not implement this function, the tty core will append the
+ * character to the circular buffer and then call start_tx() / stop_tx()
+ * to flush the data out.
+ *
+ * Do not transmit if @ch == '\0' (%__DISABLED_CHAR).
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @stop_rx: ``void ()(struct uart_port *port)``
+ *
+ * Stop receiving characters; the @port is in the process of being closed.
+ *
+ * Locking: @port->lock taken.
+ * Interrupts: locally disabled.
+ * This call must not sleep
+ *
+ * @enable_ms: ``void ()(struct uart_port *port)``
+ *
+ * Enable the modem status interrupts.
+ *
+ * This method may be called multiple times. Modem status interrupts
+ * should be disabled when the @shutdown() method is called.
+ *
+ * Locking: @port->lock taken.
+ * Interrupts: locally disabled.
+ * This call must not sleep
+ *
+ * @break_ctl: ``void ()(struct uart_port *port, int ctl)``
+ *
+ * Control the transmission of a break signal. If @ctl is nonzero, the
+ * break signal should be transmitted. The signal should be terminated
+ * when another call is made with a zero @ctl.
+ *
+ * Locking: caller holds tty_port->mutex
+ *
+ * @startup: ``int ()(struct uart_port *port)``
+ *
+ * Grab any interrupt resources and initialise any low level driver state.
+ * Enable the port for reception. It should not activate RTS nor DTR;
+ * this will be done via a separate call to @set_mctrl().
+ *
+ * This method will only be called when the port is initially opened.
+ *
+ * Locking: port_sem taken.
+ * Interrupts: globally disabled.
+ *
+ * @shutdown: ``void ()(struct uart_port *port)``
+ *
+ * Disable the @port, disable any break condition that may be in effect,
+ * and free any interrupt resources. It should not disable RTS nor DTR;
+ * this will have already been done via a separate call to @set_mctrl().
+ *
+ * Drivers must not access @port->state once this call has completed.
+ *
+ * This method will only be called when there are no more users of this
+ * @port.
+ *
+ * Locking: port_sem taken.
+ * Interrupts: caller dependent.
+ *
+ * @flush_buffer: ``void ()(struct uart_port *port)``
+ *
+ * Flush any write buffers, reset any DMA state and stop any ongoing DMA
+ * transfers.
+ *
+ * This will be called whenever the @port->state->xmit circular buffer is
+ * cleared.
+ *
+ * Locking: @port->lock taken.
+ * Interrupts: locally disabled.
+ * This call must not sleep
+ *
+ * @set_termios: ``void ()(struct uart_port *port, struct ktermios *new,
+ * struct ktermios *old)``
+ *
+ * Change the @port parameters, including word length, parity, stop bits.
+ * Update @port->read_status_mask and @port->ignore_status_mask to
+ * indicate the types of events we are interested in receiving. Relevant
+ * ktermios::c_cflag bits are:
+ *
+ * - %CSIZE - word size
+ * - %CSTOPB - 2 stop bits
+ * - %PARENB - parity enable
+ * - %PARODD - odd parity (when %PARENB is in force)
+ * - %ADDRB - address bit (changed through uart_port::rs485_config()).
+ * - %CREAD - enable reception of characters (if not set, still receive
+ * characters from the port, but throw them away).
+ * - %CRTSCTS - if set, enable CTS status change reporting.
+ * - %CLOCAL - if not set, enable modem status change reporting.
+ *
+ * Relevant ktermios::c_iflag bits are:
+ *
+ * - %INPCK - enable frame and parity error events to be passed to the TTY
+ * layer.
+ * - %BRKINT / %PARMRK - both of these enable break events to be passed to
+ * the TTY layer.
+ * - %IGNPAR - ignore parity and framing errors.
+ * - %IGNBRK - ignore break errors. If %IGNPAR is also set, ignore overrun
+ * errors as well.
+ *
+ * The interaction of the ktermios::c_iflag bits is as follows (parity
+ * error given as an example):
+ *
+ * ============ ======= ======= =========================================
+ * Parity error INPCK IGNPAR
+ * ============ ======= ======= =========================================
+ * n/a 0 n/a character received, marked as %TTY_NORMAL
+ * None 1 n/a character received, marked as %TTY_NORMAL
+ * Yes 1 0 character received, marked as %TTY_PARITY
+ * Yes 1 1 character discarded
+ * ============ ======= ======= =========================================
+ *
+ * Other flags may be used (eg, xon/xoff characters) if your hardware
+ * supports hardware "soft" flow control.
+ *
+ * Locking: caller holds tty_port->mutex
+ * Interrupts: caller dependent.
+ * This call must not sleep
+ *
+ * @set_ldisc: ``void ()(struct uart_port *port, struct ktermios *termios)``
+ *
+ * Notifier for discipline change. See
+ * Documentation/driver-api/tty/tty_ldisc.rst.
+ *
+ * Locking: caller holds tty_port->mutex
+ *
+ * @pm: ``void ()(struct uart_port *port, unsigned int state,
+ * unsigned int oldstate)``
+ *
+ * Perform any power management related activities on the specified @port.
+ * @state indicates the new state (defined by enum uart_pm_state),
+ * @oldstate indicates the previous state.
+ *
+ * This function should not be used to grab any resources.
+ *
+ * This will be called when the @port is initially opened and finally
+ * closed, except when the @port is also the system console. This will
+ * occur even if %CONFIG_PM is not set.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @type: ``const char *()(struct uart_port *port)``
+ *
+ * Return a pointer to a string constant describing the specified @port,
+ * or return %NULL, in which case the string 'unknown' is substituted.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @release_port: ``void ()(struct uart_port *port)``
+ *
+ * Release any memory and IO region resources currently in use by the
+ * @port.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @request_port: ``int ()(struct uart_port *port)``
+ *
+ * Request any memory and IO region resources required by the port. If any
+ * fail, no resources should be registered when this function returns, and
+ * it should return -%EBUSY on failure.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @config_port: ``void ()(struct uart_port *port, int type)``
+ *
+ * Perform any autoconfiguration steps required for the @port. @type
+ * contains a bit mask of the required configuration. %UART_CONFIG_TYPE
+ * indicates that the port requires detection and identification.
+ * @port->type should be set to the type found, or %PORT_UNKNOWN if no
+ * port was detected.
+ *
+ * %UART_CONFIG_IRQ indicates autoconfiguration of the interrupt signal,
+ * which should be probed using standard kernel autoprobing techniques.
+ * This is not necessary on platforms where ports have interrupts
+ * internally hard wired (eg, system on a chip implementations).
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @verify_port: ``int ()(struct uart_port *port,
+ * struct serial_struct *serinfo)``
+ *
+ * Verify the new serial port information contained within @serinfo is
+ * suitable for this port type.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @ioctl: ``int ()(struct uart_port *port, unsigned int cmd,
+ * unsigned long arg)``
+ *
+ * Perform any port specific IOCTLs. IOCTL commands must be defined using
+ * the standard numbering system found in <asm/ioctl.h>.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ *
+ * @poll_init: ``int ()(struct uart_port *port)``
+ *
+ * Called by kgdb to perform the minimal hardware initialization needed to
+ * support @poll_put_char() and @poll_get_char(). Unlike @startup(), this
+ * should not request interrupts.
+ *
+ * Locking: %tty_mutex and tty_port->mutex taken.
+ * Interrupts: n/a.
+ *
+ * @poll_put_char: ``void ()(struct uart_port *port, unsigned char ch)``
+ *
+ * Called by kgdb to write a single character @ch directly to the serial
+ * @port. It can and should block until there is space in the TX FIFO.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ * This call must not sleep
+ *
+ * @poll_get_char: ``int ()(struct uart_port *port)``
+ *
+ * Called by kgdb to read a single character directly from the serial
+ * port. If data is available, it should be returned; otherwise the
+ * function should return %NO_POLL_CHAR immediately.
+ *
+ * Locking: none.
+ * Interrupts: caller dependent.
+ * This call must not sleep
*/
struct uart_ops {
unsigned int (*tx_empty)(struct uart_port *);
void (*set_ldisc)(struct uart_port *, struct ktermios *);
void (*pm)(struct uart_port *, unsigned int state,
unsigned int oldstate);
-
- /*
- * Return a string describing the type of the port
- */
const char *(*type)(struct uart_port *);
-
- /*
- * Release IO and memory resources used by the port.
- * This includes iounmap if necessary.
- */
void (*release_port)(struct uart_port *);
-
- /*
- * Request IO and memory resources used by the port.
- * This includes iomapping the port if necessary.
- */
int (*request_port)(struct uart_port *);
void (*config_port)(struct uart_port *, int);
int (*verify_port)(struct uart_port *, struct serial_struct *);
git.samba.org / sfrench / cifs-2.6.git / blobdiff