On Sat, Mar 13, 2010 at 02:47:52PM +0000, James Simmons wrote:
>
> For the fbdev layer the you have your struct fb_var_screeninfo and also
> struct fb_videomode. The struct fb_videomode was developed for the modes
> database we have. Struct fb_var_screeninfo is more than just resolution
> data which is why we create struct fb_videomode. The really nice thing
> is that the conversion from fb_var to fb_videomode always fixes the
> pixclock to the proper values so you don't need the pixclock = 0 work
> around. I tested this patch with the intelfb driver and had no problem.
> I have used it in the past with a KMS enabled tdfx drver I wrote. In the
> future this function can be used for fbdev level mode setting. Please try
> it out and i hope it can be merged. Thanks.
>
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index 5054970..467ac68 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -581,6 +581,60 @@ int drm_fb_helper_setcolreg(unsigned regno,
> }
> EXPORT_SYMBOL(drm_fb_helper_setcolreg);
>
> +void drm_display_mode_to_fbmode(struct drm_display_mode *mode,
> + struct fb_videomode *fbmode)
> +{
> + fbmode->xres = mode->hdisplay;
> + fbmode->yres = mode->vdisplay;
> + fbmode->right_margin = mode->hsync_start - mode->hdisplay;
> + fbmode->lower_margin = mode->vsync_start - mode->vdisplay;
> + fbmode->hsync_len = mode->hsync_end - mode->hsync_start;
> + fbmode->vsync_len = mode->vsync_end - mode->vsync_start;
> + fbmode->left_margin = mode->htotal - mode->hsync_end;
> + fbmode->upper_margin = mode->vtotal - mode->vsync_end;
> + fbmode->refresh = mode->vrefresh;
> + fbmode->name = mode->name;
Is there some guarantee that mode won't be freed before fbmode? That
would leave fbmode->name pointing to invalid memory.
> +
> + if (mode->flags & DRM_MODE_FLAG_INTERLACE)
> + fbmode->vmode |= FB_VMODE_INTERLACED;
> +
> + if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
> + fbmode->vmode |= FB_VMODE_DOUBLE;
> +
What about the sync flags?
> + /* Doing a var to fb_videomode always create a proper pixclock
> + * we can trust, but the reverse is not true. So we create
> + * a proper pixclock from the refresh rate wanted. */
> + fbmode->pixclock = mode->vrefresh * mode->vtotal;
> + fbmode->pixclock *= mode->htotal;
> + fbmode->pixclock /= 1000;
> + fbmode->pixclock = KHZ2PICOS(fbmode->pixclock);
> +}
> +EXPORT_SYMBOL(drm_display_mode_to_fbmode);
> +
> +void fbmode_to_drm_display_mode(struct fb_videomode *fbmode,
> + struct drm_display_mode *mode)
> +{
> + mode->hdisplay = fbmode->xres;
> + mode->vdisplay = fbmode->yres;
> + mode->hsync_start = mode->hdisplay + fbmode->right_margin;
> + mode->vsync_start = mode->vdisplay + fbmode->lower_margin;
> + mode->hsync_end = mode->hsync_start + fbmode->hsync_len;
> + mode->vsync_end = mode->vsync_start + fbmode->vsync_len;
> + mode->htotal = mode->hsync_end + fbmode->left_margin;
> + mode->vtotal = mode->vsync_end + fbmode->upper_margin;
> + mode->vrefresh = fbmode->refresh;
> + mode->clock = PICOS2KHZ(fbmode->pixclock);
> +
> + if ((fbmode->vmode & FB_VMODE_MASK) == FB_VMODE_INTERLACED)
> + mode->flags |= DRM_MODE_FLAG_INTERLACE;
> +
> + if ((fbmode->vmode & FB_VMODE_MASK) == FB_VMODE_DOUBLE)
> + mode->flags |= DRM_MODE_FLAG_DBLSCAN;
Is interlaced+dblscan considered an invalid combination? The conversion
to the other direction didn't make that assumption.
--
Ville Syrjälä
syrjala@xxxxxx
http://www.sci.fi/~syrjala/
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