[PATCH v3 0/5] fbcon,vgacon,vt: Share helpers for text cursors
From: Thomas Zimmermann <tzimmermann@suse.de>
Date: 2026-09-28 08:57:39
Also in:
dri-devel, linux-serial, sashiko-reviews
VT consoles fbcon and vgacon implement various cursor sizes (i.e.,
underline, block, half-block, etc). Share related code and harmonize
the look and behaviour.
In patches 1 to 3, move VT cursor-size calculations to the VT subsystem
and use the new helpers from vgacon. Replace similar code in the console.
The new helpers also take VT's default cursor size into account.
Fbcon implements a custom helper that creates a cursor glyph for the
given cursor size. In patches 4 and 5, move the code into the font
library and update fbcon to use the new helper. The cursor-glyph shape
rendering is tied to the font in use. Hence move them next to each other.
Also update fbcon to use the shared cursor-size helpers.
Tested with fbcon under bochs (qemu) and with vgacon on an old SiS
6202 VGA card. Other consoles (newport_con, sticon) don't support cursor
sizes, so leave them as-is.
v3:
- mention user interfaces to control cursor size in commit message (GregKH)
- elaborate defaults (GregKH)
- move retry logic into helper
- handle CUR_DEF
v2:
- restore vc_cell_height in vgacon
- avoid interference from concurrent user space
- fix docs
Thomas Zimmermann (5):
vt: Add cursor-size helpers
vgacon: Remove trailing whitespaces
vgacon: Use vt_cursor_{start,end}()
lib/fonts: Add font_glyph_cursor() helper
fbcon: Replace fbcon_fill_cursor_mask() with fbcon_cursor_glyph()
drivers/tty/vt/vt.c | 104 +++++++++++++++++++++++++++
drivers/video/console/vgacon.c | 43 +++--------
drivers/video/fbdev/core/bitblit.c | 3 +-
drivers/video/fbdev/core/fbcon.c | 45 +++---------
drivers/video/fbdev/core/fbcon.h | 2 +-
drivers/video/fbdev/core/fbcon_ccw.c | 3 +-
drivers/video/fbdev/core/fbcon_cw.c | 3 +-
drivers/video/fbdev/core/fbcon_ud.c | 3 +-
include/linux/console_struct.h | 7 ++
include/linux/font.h | 4 ++
lib/fonts/Makefile | 3 +-
lib/fonts/font_cursor.c | 56 +++++++++++++++
12 files changed, 199 insertions(+), 77 deletions(-)
create mode 100644 lib/fonts/font_cursor.c
base-commit: ff831af91674990f9f1814340860e96943d5df1a
prerequisite-patch-id: c67e5d886a47b7d0266d81100837557fda34cb24
prerequisite-patch-id: a5a973e527c88a5b47053d7a72aefe0b550197cb
prerequisite-patch-id: b9adc9622920a3e70168e672c2c92795b3e3a106
prerequisite-patch-id: 5030de433a01c2e99056cadb676a8e2ba35f055a
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2.55.0