From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wang YanQing <udknight@gmail.com>
Date: Mon, 12 May 2014 08:48:29 +0000
Subject: Re: [PATCH] uvesafb: abort initialization if video=uvesafb is not set
Message-Id: <20140512084829.GA7007@udknight>
List-Id: <linux-fbdev.vger.kernel.org>
References: <1396791873-22606-1-git-send-email-lxnay@sabayon.org>
In-Reply-To: <1396791873-22606-1-git-send-email-lxnay@sabayon.org>
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To: linux-fbdev@vger.kernel.org

On Fri, May 09, 2014 at 01:06:44PM +0300, Tomi Valkeinen wrote:
> On 06/04/14 16:44, lxnay@sabayon.org wrote:
> > From: Fabio Erculiani <lxnay@sabayon.org>
> > 
> > This patch makes possible to ship kernels with both vesafb and uvesafb
> > in order to guarantee a smooth transition to uvesafb and cope with
> > potential incompatibiles introduced by uvesafb making possible to disable
> > it via cmdline.
> > 
> > In case both vesafb and uvesafb are built-in, the kernel will try to
> > initialize both, which makes possible to select the wanted one using
> > either video=vesafb:... or video=uvesafb:....
> > In this way, old distro installations will keep working as before while
> > new ones can adopt video=uvesafb.
> > 
> > The behaviour does not change if uvesafb is built as a module.
> > ---
> >  drivers/video/uvesafb.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> > 
> > diff --git a/drivers/video/uvesafb.c b/drivers/video/uvesafb.c
> > index d428445..04c4742 100644
> > --- a/drivers/video/uvesafb.c
> > +++ b/drivers/video/uvesafb.c
> > @@ -1957,6 +1957,10 @@ static int uvesafb_init(void)
> >  
> >  	if (fb_get_options("uvesafb", &option))
> >  		return -ENODEV;
> > +	if (!option || !*option)
> > +		/* if vesafb is enabled, this will make possible to fallback to it */
> > +		return -ENODEV;
> > +
> >  	uvesafb_setup(option);
> >  #endif
> >  	err = cn_add_callback(&uvesafb_cn_id, "uvesafb", uvesafb_cn_callback);
> > 
I don't think it is right, this patch force uvesafb user to set uvesafb kernel cmdline
options, but what about the default setting? If user use UVESAFB_DEFAULT_MODE before, then
he or she have to add useless cmdline options to make uvesafb work for it in future kernel.

Thanks.