| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 1 | /* |
| 2 | * linux/drivers/video/dummycon.c -- A dummy console driver |
| 3 | * |
| 4 | * To be used if there's no other console driver (e.g. for plain VGA text) |
| 5 | * available, usually until fbcon takes console over. |
| 6 | */ |
| 7 | |
| 8 | #include <linux/types.h> |
| 9 | #include <linux/kdev_t.h> |
| 10 | #include <linux/console.h> |
| 11 | #include <linux/vt_kern.h> |
| 12 | #include <linux/screen_info.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/module.h> |
| 15 | |
| 16 | /* |
| 17 | * Dummy console driver |
| 18 | */ |
| 19 | |
| 20 | #if defined(__arm__) |
| 21 | #define DUMMY_COLUMNS screen_info.orig_video_cols |
| 22 | #define DUMMY_ROWS screen_info.orig_video_lines |
| 23 | #else |
| 24 | /* set by Kconfig. Use 80x25 for 640x480 and 160x64 for 1280x1024 */ |
| 25 | #define DUMMY_COLUMNS CONFIG_DUMMY_CONSOLE_COLUMNS |
| 26 | #define DUMMY_ROWS CONFIG_DUMMY_CONSOLE_ROWS |
| 27 | #endif |
| 28 | |
| 29 | static const char *dummycon_startup(void) |
| 30 | { |
| 31 | return "dummy device"; |
| 32 | } |
| 33 | |
| 34 | static void dummycon_init(struct vc_data *vc, int init) |
| 35 | { |
| 36 | vc->vc_can_do_color = 1; |
| 37 | if (init) { |
| 38 | vc->vc_cols = DUMMY_COLUMNS; |
| 39 | vc->vc_rows = DUMMY_ROWS; |
| 40 | } else |
| 41 | vc_resize(vc, DUMMY_COLUMNS, DUMMY_ROWS); |
| 42 | } |
| 43 | |
| 44 | static void dummycon_deinit(struct vc_data *vc) { } |
| 45 | static void dummycon_clear(struct vc_data *vc, int sy, int sx, int height, |
| 46 | int width) { } |
| 47 | static void dummycon_putc(struct vc_data *vc, int c, int ypos, int xpos) { } |
| 48 | static void dummycon_putcs(struct vc_data *vc, const unsigned short *s, |
| 49 | int count, int ypos, int xpos) { } |
| 50 | static void dummycon_cursor(struct vc_data *vc, int mode) { } |
| 51 | |
| 52 | static bool dummycon_scroll(struct vc_data *vc, unsigned int top, |
| 53 | unsigned int bottom, enum con_scroll dir, |
| 54 | unsigned int lines) |
| 55 | { |
| 56 | return false; |
| 57 | } |
| 58 | |
| 59 | static int dummycon_switch(struct vc_data *vc) |
| 60 | { |
| 61 | return 0; |
| 62 | } |
| 63 | |
| 64 | static int dummycon_blank(struct vc_data *vc, int blank, int mode_switch) |
| 65 | { |
| 66 | return 0; |
| 67 | } |
| 68 | |
| 69 | static int dummycon_font_set(struct vc_data *vc, struct console_font *font, |
| 70 | unsigned int flags) |
| 71 | { |
| 72 | return 0; |
| 73 | } |
| 74 | |
| 75 | static int dummycon_font_default(struct vc_data *vc, |
| 76 | struct console_font *font, char *name) |
| 77 | { |
| 78 | return 0; |
| 79 | } |
| 80 | |
| 81 | static int dummycon_font_copy(struct vc_data *vc, int con) |
| 82 | { |
| 83 | return 0; |
| 84 | } |
| 85 | |
| 86 | /* |
| 87 | * The console `switch' structure for the dummy console |
| 88 | * |
| 89 | * Most of the operations are dummies. |
| 90 | */ |
| 91 | |
| 92 | const struct consw dummy_con = { |
| 93 | .owner = THIS_MODULE, |
| 94 | .con_startup = dummycon_startup, |
| 95 | .con_init = dummycon_init, |
| 96 | .con_deinit = dummycon_deinit, |
| 97 | .con_clear = dummycon_clear, |
| 98 | .con_putc = dummycon_putc, |
| 99 | .con_putcs = dummycon_putcs, |
| 100 | .con_cursor = dummycon_cursor, |
| 101 | .con_scroll = dummycon_scroll, |
| 102 | .con_switch = dummycon_switch, |
| 103 | .con_blank = dummycon_blank, |
| 104 | .con_font_set = dummycon_font_set, |
| 105 | .con_font_default = dummycon_font_default, |
| 106 | .con_font_copy = dummycon_font_copy, |
| 107 | }; |
| 108 | EXPORT_SYMBOL_GPL(dummy_con); |