Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
| 2 | /* |
| 3 | * hvc_console.h |
| 4 | * Copyright (C) 2005 IBM Corporation |
| 5 | * |
| 6 | * Author(s): |
| 7 | * Ryan S. Arnold <rsa@us.ibm.com> |
| 8 | * |
| 9 | * hvc_console header information: |
| 10 | * moved here from arch/powerpc/include/asm/hvconsole.h |
| 11 | * and drivers/char/hvc_console.c |
| 12 | */ |
| 13 | |
| 14 | #ifndef HVC_CONSOLE_H |
| 15 | #define HVC_CONSOLE_H |
| 16 | #include <linux/kref.h> |
| 17 | #include <linux/tty.h> |
| 18 | #include <linux/spinlock.h> |
| 19 | |
| 20 | /* |
| 21 | * This is the max number of console adapters that can/will be found as |
| 22 | * console devices on first stage console init. Any number beyond this range |
| 23 | * can't be used as a console device but is still a valid tty device. |
| 24 | */ |
| 25 | #define MAX_NR_HVC_CONSOLES 16 |
| 26 | |
| 27 | /* |
| 28 | * The Linux TTY code does not support dynamic addition of tty derived devices |
| 29 | * so we need to know how many tty devices we might need when space is allocated |
| 30 | * for the tty device. Since this driver supports hotplug of vty adapters we |
| 31 | * need to make sure we have enough allocated. |
| 32 | */ |
| 33 | #define HVC_ALLOC_TTY_ADAPTERS 8 |
| 34 | |
| 35 | struct hvc_struct { |
| 36 | struct tty_port port; |
| 37 | spinlock_t lock; |
| 38 | int index; |
| 39 | int do_wakeup; |
| 40 | char *outbuf; |
| 41 | int outbuf_size; |
| 42 | int n_outbuf; |
| 43 | uint32_t vtermno; |
| 44 | const struct hv_ops *ops; |
| 45 | int irq_requested; |
| 46 | int data; |
| 47 | struct winsize ws; |
| 48 | struct work_struct tty_resize; |
| 49 | struct list_head next; |
| 50 | unsigned long flags; |
| 51 | }; |
| 52 | |
| 53 | /* implemented by a low level driver */ |
| 54 | struct hv_ops { |
| 55 | int (*get_chars)(uint32_t vtermno, char *buf, int count); |
| 56 | int (*put_chars)(uint32_t vtermno, const char *buf, int count); |
| 57 | int (*flush)(uint32_t vtermno, bool wait); |
| 58 | |
| 59 | /* Callbacks for notification. Called in open, close and hangup */ |
| 60 | int (*notifier_add)(struct hvc_struct *hp, int irq); |
| 61 | void (*notifier_del)(struct hvc_struct *hp, int irq); |
| 62 | void (*notifier_hangup)(struct hvc_struct *hp, int irq); |
| 63 | |
| 64 | /* tiocmget/set implementation */ |
| 65 | int (*tiocmget)(struct hvc_struct *hp); |
| 66 | int (*tiocmset)(struct hvc_struct *hp, unsigned int set, unsigned int clear); |
| 67 | |
| 68 | /* Callbacks to handle tty ports */ |
| 69 | void (*dtr_rts)(struct hvc_struct *hp, int raise); |
| 70 | }; |
| 71 | |
| 72 | /* Register a vterm and a slot index for use as a console (console_init) */ |
| 73 | extern int hvc_instantiate(uint32_t vtermno, int index, |
| 74 | const struct hv_ops *ops); |
| 75 | |
| 76 | /* register a vterm for hvc tty operation (module_init or hotplug add) */ |
| 77 | extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data, |
| 78 | const struct hv_ops *ops, int outbuf_size); |
| 79 | /* remove a vterm from hvc tty operation (module_exit or hotplug remove) */ |
| 80 | extern int hvc_remove(struct hvc_struct *hp); |
| 81 | |
| 82 | /* data available */ |
| 83 | int hvc_poll(struct hvc_struct *hp); |
| 84 | void hvc_kick(void); |
| 85 | |
| 86 | /* Resize hvc tty terminal window */ |
| 87 | extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws); |
| 88 | |
| 89 | static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws) |
| 90 | { |
| 91 | unsigned long flags; |
| 92 | |
| 93 | spin_lock_irqsave(&hp->lock, flags); |
| 94 | __hvc_resize(hp, ws); |
| 95 | spin_unlock_irqrestore(&hp->lock, flags); |
| 96 | } |
| 97 | |
| 98 | /* default notifier for irq based notification */ |
| 99 | extern int notifier_add_irq(struct hvc_struct *hp, int data); |
| 100 | extern void notifier_del_irq(struct hvc_struct *hp, int data); |
| 101 | extern void notifier_hangup_irq(struct hvc_struct *hp, int data); |
| 102 | |
| 103 | |
| 104 | #if defined(CONFIG_XMON) && defined(CONFIG_SMP) |
| 105 | #include <asm/xmon.h> |
| 106 | #else |
| 107 | static inline int cpus_are_in_xmon(void) |
| 108 | { |
| 109 | return 0; |
| 110 | } |
| 111 | #endif |
| 112 | |
| 113 | #endif // HVC_CONSOLE_H |