From 717a5651b10940ec827fe07acfb956d906250b2b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 9 Jan 2023 11:13:54 +0106 Subject: console: Use BIT() macros for @flags values Rather than manually calculating powers of 2, use the BIT() macros. Also take this opportunatity to cleanup and restructure the value comments into proper kerneldoc comments. Signed-off-by: Thomas Gleixner Signed-off-by: John Ogness Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230109100800.1085541-3-john.ogness@linutronix.de --- include/linux/console.h | 46 ++++++++++++++++++++++++++++++++++++---------- 1 file changed, 36 insertions(+), 10 deletions(-) (limited to 'include/linux/console.h') diff --git a/include/linux/console.h b/include/linux/console.h index 9cea254b34b8..ed804dd7c2e8 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -15,6 +15,7 @@ #define _LINUX_CONSOLE_H_ 1 #include +#include #include #include @@ -125,18 +126,43 @@ static inline int con_debug_leave(void) /* * The interface for a console, or any other device that wants to capture * console messages (printer driver?) - * - * If a console driver is marked CON_BOOT then it will be auto-unregistered - * when the first real console is registered. This is for early-printk drivers. */ -#define CON_PRINTBUFFER (1) -#define CON_CONSDEV (2) /* Preferred console, /dev/console */ -#define CON_ENABLED (4) -#define CON_BOOT (8) -#define CON_ANYTIME (16) /* Safe to call when cpu is offline */ -#define CON_BRL (32) /* Used for a braille device */ -#define CON_EXTENDED (64) /* Use the extended output format a la /dev/kmsg */ +/** + * cons_flags - General console flags + * @CON_PRINTBUFFER: Used by newly registered consoles to avoid duplicate + * output of messages that were already shown by boot + * consoles or read by userspace via syslog() syscall. + * @CON_CONSDEV: Indicates that the console driver is backing + * /dev/console. + * @CON_ENABLED: Indicates if a console is allowed to print records. If + * false, the console also will not advance to later + * records. + * @CON_BOOT: Marks the console driver as early console driver which + * is used during boot before the real driver becomes + * available. It will be automatically unregistered + * when the real console driver is registered unless + * "keep_bootcon" parameter is used. + * @CON_ANYTIME: A misnomed historical flag which tells the core code + * that the legacy @console::write callback can be invoked + * on a CPU which is marked OFFLINE. That is misleading as + * it suggests that there is no contextual limit for + * invoking the callback. The original motivation was + * readiness of the per-CPU areas. + * @CON_BRL: Indicates a braille device which is exempt from + * receiving the printk spam for obvious reasons. + * @CON_EXTENDED: The console supports the extended output format of + * /dev/kmesg which requires a larger output buffer. + */ +enum cons_flags { + CON_PRINTBUFFER = BIT(0), + CON_CONSDEV = BIT(1), + CON_ENABLED = BIT(2), + CON_BOOT = BIT(3), + CON_ANYTIME = BIT(4), + CON_BRL = BIT(5), + CON_EXTENDED = BIT(6), +}; struct console { char name[16]; -- cgit v1.2.3 From 02b2396d7d0cf806e80c887b4c799d482d6977ed Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Mon, 9 Jan 2023 11:13:55 +0106 Subject: console: Document struct console Add kerneldoc comments to struct console. Signed-off-by: Thomas Gleixner Signed-off-by: John Ogness Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230109100800.1085541-4-john.ogness@linutronix.de --- include/linux/console.h | 54 +++++++++++++++++++++++++++++++++---------------- 1 file changed, 37 insertions(+), 17 deletions(-) (limited to 'include/linux/console.h') diff --git a/include/linux/console.h b/include/linux/console.h index ed804dd7c2e8..1e36958aa656 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -164,24 +164,44 @@ enum cons_flags { CON_EXTENDED = BIT(6), }; +/** + * struct console - The console descriptor structure + * @name: The name of the console driver + * @write: Write callback to output messages (Optional) + * @read: Read callback for console input (Optional) + * @device: The underlying TTY device driver (Optional) + * @unblank: Callback to unblank the console (Optional) + * @setup: Callback for initializing the console (Optional) + * @exit: Callback for teardown of the console (Optional) + * @match: Callback for matching a console (Optional) + * @flags: Console flags. See enum cons_flags + * @index: Console index, e.g. port number + * @cflag: TTY control mode flags + * @ispeed: TTY input speed + * @ospeed: TTY output speed + * @seq: Sequence number of the next ringbuffer record to print + * @dropped: Number of unreported dropped ringbuffer records + * @data: Driver private data + * @node: hlist node for the console list + */ struct console { - char name[16]; - void (*write)(struct console *, const char *, unsigned); - int (*read)(struct console *, char *, unsigned); - struct tty_driver *(*device)(struct console *, int *); - void (*unblank)(void); - int (*setup)(struct console *, char *); - int (*exit)(struct console *); - int (*match)(struct console *, char *name, int idx, char *options); - short flags; - short index; - int cflag; - uint ispeed; - uint ospeed; - u64 seq; - unsigned long dropped; - void *data; - struct hlist_node node; + char name[16]; + void (*write)(struct console *co, const char *s, unsigned int count); + int (*read)(struct console *co, char *s, unsigned int count); + struct tty_driver *(*device)(struct console *co, int *index); + void (*unblank)(void); + int (*setup)(struct console *co, char *options); + int (*exit)(struct console *co); + int (*match)(struct console *co, char *name, int idx, char *options); + short flags; + short index; + int cflag; + uint ispeed; + uint ospeed; + u64 seq; + unsigned long dropped; + void *data; + struct hlist_node node; }; #ifdef CONFIG_LOCKDEP -- cgit v1.2.3