1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * udbg interface to hvc_console.c |
4 | * |
5 | * (C) Copyright David Gibson, IBM Corporation 2008. |
6 | */ |
7 | |
8 | #include <linux/console.h> |
9 | #include <linux/delay.h> |
10 | #include <linux/err.h> |
11 | #include <linux/init.h> |
12 | #include <linux/moduleparam.h> |
13 | #include <linux/types.h> |
14 | #include <linux/irq.h> |
15 | |
16 | #include <asm/udbg.h> |
17 | |
18 | #include "hvc_console.h" |
19 | |
20 | static struct hvc_struct *hvc_udbg_dev; |
21 | |
22 | static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count) |
23 | { |
24 | int i; |
25 | |
26 | for (i = 0; i < count && udbg_putc; i++) |
27 | udbg_putc(buf[i]); |
28 | |
29 | return i; |
30 | } |
31 | |
32 | static int hvc_udbg_get(uint32_t vtermno, char *buf, int count) |
33 | { |
34 | int i, c; |
35 | |
36 | if (!udbg_getc_poll) |
37 | return 0; |
38 | |
39 | for (i = 0; i < count; i++) { |
40 | if ((c = udbg_getc_poll()) == -1) |
41 | break; |
42 | buf[i] = c; |
43 | } |
44 | |
45 | return i; |
46 | } |
47 | |
48 | static const struct hv_ops hvc_udbg_ops = { |
49 | .get_chars = hvc_udbg_get, |
50 | .put_chars = hvc_udbg_put, |
51 | }; |
52 | |
53 | static int __init hvc_udbg_init(void) |
54 | { |
55 | struct hvc_struct *hp; |
56 | |
57 | if (!udbg_putc) |
58 | return -ENODEV; |
59 | |
60 | BUG_ON(hvc_udbg_dev); |
61 | |
62 | hp = hvc_alloc(vtermno: 0, data: 0, ops: &hvc_udbg_ops, outbuf_size: 16); |
63 | if (IS_ERR(ptr: hp)) |
64 | return PTR_ERR(ptr: hp); |
65 | |
66 | hvc_udbg_dev = hp; |
67 | |
68 | return 0; |
69 | } |
70 | device_initcall(hvc_udbg_init); |
71 | |
72 | static int __init hvc_udbg_console_init(void) |
73 | { |
74 | if (!udbg_putc) |
75 | return -ENODEV; |
76 | |
77 | hvc_instantiate(vtermno: 0, index: 0, ops: &hvc_udbg_ops); |
78 | add_preferred_console(name: "hvc" , idx: 0, NULL); |
79 | |
80 | return 0; |
81 | } |
82 | console_initcall(hvc_udbg_console_init); |
83 | |