Re: [PATCH 1/2] vt: add cursor blink interval escape sequence

Scot Doyle
2015-03-14T17:48:13Z

On Fri, 27 Feb 2015, Scot Doyle wrote:
> Add an escape sequence to specify the current console's cursor blink
> interval. The interval is specified as a number of milliseconds until
> the next cursor display state toggle, from 50 to 65535. /proc/loadavg
> did not show a difference with a one msec interval, but the lower
> bound is set to 50 msecs since slower hardware wasn't tested.
>
> Store the interval in the vc_data structure for later access by fbcon,
> initializing the value to fbcon's current hardcoded value of 200 msecs.
>
> Signed-off-by: Scot Doyle <lkml14-enLWO88E2pdl57MIdRCFDg@public.gmane.org>
> Acked-by: Pavel Machek <pavel-+ZI9xUNit7I@public.gmane.org>

Hi Greg, sorry about your backlog. Is it too soon for a ping?

> ---
> drivers/tty/vt/vt.c | 9 +++++++++
> include/linux/console_struct.h | 1 +
> 2 files changed, 10 insertions(+)
>
> diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
> index 6e00572..ab1f173 100644
> --- a/drivers/tty/vt/vt.c
> +++ b/drivers/tty/vt/vt.c
> @@ -135,6 +135,7 @@ const struct consw *conswitchp;
> */
> #define DEFAULT_BELL_PITCH 750
> #define DEFAULT_BELL_DURATION (HZ/8)
> +#define DEFAULT_CURSOR_BLINK_MS 200
>
> struct vc vc_cons [MAX_NR_CONSOLES];
>
> @@ -1590,6 +1591,13 @@ static void setterm_command(struct vc_data *vc)
> case 15: /* activate the previous console */
> set_console(last_console);
> break;
> + case 16: /* set cursor blink duration in msec */
> + if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
> + vc->vc_par[1] <= USHRT_MAX)
> + vc->vc_cur_blink_ms = vc->vc_par[1];
> + else
> + vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
> + break;
> }
> }
>
> @@ -1717,6 +1725,7 @@ static void reset_terminal(struct vc_data *vc, int do_clear)
>
> vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
> vc->vc_bell_duration = DEFAULT_BELL_DURATION;
> + vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
>
> gotoxy(vc, 0, 0);
> save_cur(vc);
> diff --git a/include/linux/console_struct.h b/include/linux/console_struct.h
> index e859c98..e329ee2 100644
> --- a/include/linux/console_struct.h
> +++ b/include/linux/console_struct.h
> @@ -104,6 +104,7 @@ struct vc_data {
> unsigned int vc_resize_user; /* resize request from user */
> unsigned int vc_bell_pitch; /* Console bell pitch */
> unsigned int vc_bell_duration; /* Console bell duration */
> + unsigned short vc_cur_blink_ms; /* Cursor blink duration */
> struct vc_data **vc_display_fg; /* [!] Ptr to var holding fg console for this display */
> struct uni_pagedir *vc_uni_pagedir;
> struct uni_pagedir **vc_uni_pagedir_loc; /* [!] Location of uni_pagedir variable for this console */
> --
> 2.3.0
>