cons(9) [netbsd man page]
CONS(9) BSD Kernel Developer's Manual CONS(9) NAME
cnbell, cnflush, cngetc, cngetsn, cnhalt, cnpollc, cnputc -- console access interface SYNOPSIS
#include <dev/cons.h> void cnbell(u_int pitch, u_int period, u_int volume); void cnflush(void); int cngetc(void); int cngetsn(char *cp, int size); void cnhalt(void); void cnpollc(int on); void cnputc(int c); DESCRIPTION
These functions operate over the current console device. The console must be initialized before these functions can be used. Console input polling functions cngetc(), cngetsn() and cnpollc() are only to be used during initial system boot, e.g., when asking for root and dump device or to get necessary user input within mountroothooks. Once the system boots, user input is read via standard tty(4) facili- ties. The following is a brief description of each function: cnbell() Ring a bell at appropriate pitch, for duration of period milliseconds at given volume. Note that the volume value is ignored com- monly. cnflush() Waits for all pending output to finish. cngetc() Poll (busy wait) for an input and return the input key. Returns 0 if there is no console input device. cnpollc() must be called before cngetc() could be used. cngetc() should be used during kernel startup only. cngetsn() Read one line of user input, stop reading once the newline key is input. Input is echoed back. This uses cnpollc() and cngetc(). Number of read characters is size at maximum, user is notified by console bell when the end of input buffer is reached. <Backspace> key works as expected. <@> or <CTRL>-u make cngetsn() discard input read so far, print newline and wait for next input. cngetsn() returns number of characters actually read, excluding the final newline. cp is not zero-ended before return. cngetsn() should be used during kernel startup only. cnhalt() Terminates the console device (i.e. cleanly shuts down the console hardware.) cnpollc() Switch the console driver to polling mode if on is nonzero, or back to interrupt driven mode if on is zero. cnpollc() should be used during kernel startup only. cnputc() Console kernel output character routine. Commonly, kernel code uses printf(9) rather than using this low-level interface. EXAMPLES
This waits until a <Enter> key is pressed: int c; cnpollc(1); for(;;) { c = cngetc(); if ((c == ' ' || (c == ' ')) { printf(" "); break; } } cnpollc(0); SEE ALSO
pckbd(4), pcppi(4), tty(4), wscons(4), wskbd(4), printf(9), spl(9), wscons(9) BSD
June 8, 2010 BSD
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WSKBD(9) BSD Kernel Developer's Manual WSKBD(9) NAME
wskbd, wskbd_input, wskbd_rawinput, wskbd_cnattach, wskbd_cndetach, wskbddevprint -- wscons keyboard support SYNOPSIS
#include <dev/wscons/wsconsio.h> #include <dev/wscons/wskbdvar.h> #include <dev/wscons/wsksymdef.h> #include <dev/wscons/wsksymvar.h> void wskbd_input(struct device *kbddev, u_int type, int value); void wskbd_rawinput(struct device *kbddev, u_char *buf, int len); void wskbd_cnattach(const struct wskbd_consops *consops, void *conscookie, const struct wskbd_mapdata *mapdata); void wskbd_cndetach(); int wskbddevprint(void *aux, const char *pnp); DESCRIPTION
The wskbd module is a component of the wscons(9) framework to provide machine-independent keyboard support. Most of the support is provided by the wskbd(4) device driver, which must be a child of the hardware device driver. DATA TYPES
Keyboard drivers providing support for wscons keyboards will make use of the following data types: kbd_t An opaque type describing keyboard properties. keysym_t The wscons keyboard-independent symbolic representation of the keypress. struct wskbd_accessops A structure used to specify the keyboard access functions. All keyboards must provide this structure and pass it to the wskbd(4) child device. It has the following members: int (*enable)(void *, int); void (*set_leds)(void *, int); int (*ioctl)(void *v, u_long cmd, void *data, int flag, struct lwp *l); The enable member defines the function to be called to enable keypress passing to wscons. The set_leds member defined the function to be called to set the LEDs on the keyboard. The ioctl member defines the function to be called to perform keyboard-specific ioctl calls. There is a void * cookie provided by the keyboard driver associated with these functions, which is passed to them when they are invoked. struct wskbd_consops A structure used to specify the keyboard console operations. All keyboards which can operate as a console must provide this struc- ture and pass it to the wskbd(4) child device. If the keyboard cannot be a console, it is not necessary to specify this structure. It has the following members: void (*getc)(void *, u_int *, int *); void (*pollc)(void *, int); void (*bell)(void *, u_int, u_int, u_int); There is a void * cookie provided by the keyboard driver associated with these functions, which is passed to them when they are invoked. struct wscons_keydesc A structure used to describe a keyboard mapping table to convert keyboard-specific keycodes to wscons keysyms. It has the following members: kbd_t name; /* name of this map */ kbd_t base; /* map this one is based on */ int map_size; /* size of map */ const keysym_t *map; /* the map itself */ struct wskbd_mapdata A structure used to describe the keyboard layout and operation to interpret the keyboard layout. it contains the following members: const struct wscons_keydesc *keydesc; kbd_t layout; struct wskbddev_attach_args A structure used to attach the wskbd(4) child device. It has the following members: int console; const struct wskbd_mapdata *keymap; const struct wskbd_accessops *accessops; void *accesscookie; Keymaps Keymaps are a dense stream of keysym_t. A declaration has the following fields: pos [cmd] normal [shift] [altgr] [shift-altgr] The fields have the following meanings: pos Always specified as KC(pos) and starts the description of key pos. cmd If the command modifier (KS_Cmd_XXX) is active, the optional command cmd is invoked. normal The keysym if no modifiers are active. shift The keysym if the shift modifier is active. altgr The keysym if the alt-gr modifier is active. shift-altgr The keysym if the shift-alt-gr modifier is active. If the keysym after pos is not KS_Cmd_XXX, then cmd is empty. The shift, altgr and shift-altgr fields are determined from previous fields if they are not specified. Therefore, there are four valid keysym declarations: pos [cmd] normal pos [cmd] normal shift pos [cmd] normal shift altgr pos [cmd] normal shift altgr shift-altgr FUNCTIONS
wskbd_input(kbddev, type, value) Pass the keypress of value value and type type to wscons keyboard driver. Valid values of type are: WSCONS_EVENT_KEY_UP Key released. WSCONS_EVENT_KEY_DOWN Key pressed. wskbd_rawinput(kbddev, buf, len) Pass the raw keypress in the buffer buf to the wscons keyboard driver. The buffer is len bytes long. This function should only be called if the kernel option WSDISPLAY_COMPAT_RAWKBD is enabled. wskbd_cnattach(consops, conscookie, mapdata) Attach this keyboard as the console input by specifying the console operations consops and the keyboard mapping table information in mapdata. The functions specified in consops will be called with conscookie as the first argument. wskbd_cndetach() Detach this keyboard as the console input. wskbddevprint(aux, pnp) The default wskbd printing routine used by config_found(). (see autoconf(9)). AUTOCONFIGURATION
Keyboard drivers which want to use the wskbd module must be a parent to the wskbd(4) device and provide an attachment interface. To attach the wskbd(4) device, the keyboard driver must allocate and populate a wskbddev_attach_args structure with the supported operations and call- backs and call config_found() to perform the attach (see autoconf(9)). The keymap member points to the wskbd_mapdata structure which describes the keycode mapping operations. The accessops member points to the wskbd_accessops structure which describes the keyboard access operations. The console member is a boolean to indicate to wscons whether this keyboard will be used for console input. OPERATION
If the keyboard belongs to the system console, it must register the wskbd_consops structure specifying the console operations via wskbd_cnattach() at console attach time. When a keypress arrives from the keyboard, the keyboard driver must perform any necessary character decoding to wscons events and pass the events to wscons via wskbd_input(). If the kernel is compiled with the option WSDISPLAY_COMPAT_RAWKBD, then the keyboard driver must also pass the raw keyboard data to wscons via wskbd_rawinput(). The wscons framework calls back into the hardware driver by invoking the functions that are specified in the accessops structure. The enable() and set_leds() functions are relatively simple and self-explanatory. The ioctl() function is called by the wscons interface to per- form keyboard-specific ioctl operations (see ioctl(2)). The argument cmd to the ioctl() function specifies the specific command to perform using the data data. Valid commands are listed in sys/dev/wscons/wsconsio.h. CODE REFERENCES
The wscons subsystem is implemented within the directory sys/dev/wscons. The wskbd module itself is implement within the files sys/dev/wscons/wskbd.c and sys/dev/wscons/wskbdutil.c. ioctl(2) operations are listed in sys/dev/wscons/wsconsio.h. SEE ALSO
ioctl(2), autoconf(9), driver(9), intro(9), wsdisplay(9), wsmouse(9) BSD
December 20, 2005 BSD