Jon Smirl wrote:

The hardware mouse cursor is relevant in graphics mode because you may
not be able to generate screens in real time. If you can't the
software mouse cursor lags and may become unusable. Hardware mouse
cursor eliminates this problem.

I don't have anything against hardware cursor support for userspace. And
I don't even mind if we remove hardware cursor support for fbcon (I don't
see the benefit anyway).  What I don't want is using fbops->fb_cursor
to support a userspace hardware cursor.  In it's current incarnation
it is just wrong.  Besides being a multiplexer with a 100-byte parameter,
it also requires information that are internal to fbdev only. And even if
we manage to make it work, we'll end up with a function with a multiple
personality disorder, it behaves differently when client is fbcon, and
changes behavior again when the client is userspace.

So let's keep fbops->fb_cursor for fbcon use only.  Better yet, let fbcon
call soft_cursor unconditionally, remove hardware cursor from all drivers,
then overhaul fbops->fb_cursor. Or if people think this is too radical,
let's create a new cursor API and gradually phase out the old API, as
proposed in my previous post. Here's one:

struct fb_cursor_ops {
	int (*cursor_move)(int x, int y);
	int (*cursor_show)(int show);
	int (*cursor_load_image)(u32 *image, int width, int height);
	int (*cursor_load_color)(struct fb_cmap *cmap);
	int (*cursor_set_size)(int width, int height);
	int (*cursor_capabilities)(int set, int caps);
};

struct fb_info {
	...
	struct fb_cursor_ops *cursor_ops;
	...
};

In cursor_load_image, we can make image to be always 32-bit truecolor and
just let the driver convert it to something the hardware can support.

In cursor_capabilities, it will either set the capabilities, or get it.
int caps may be t0o small to describe the capabilities so this can be changed.

Tony

 


-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf