Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752689Ab2FFLoQ (ORCPT ); Wed, 6 Jun 2012 07:44:16 -0400 Received: from mail-lpp01m010-f46.google.com ([209.85.215.46]:44009 "EHLO mail-lpp01m010-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752249Ab2FFLoN (ORCPT ); Wed, 6 Jun 2012 07:44:13 -0400 MIME-Version: 1.0 In-Reply-To: <1338351267-25561-1-git-send-email-Ying.Liu@freescale.com> References: <1338351267-25561-1-git-send-email-Ying.Liu@freescale.com> Date: Wed, 6 Jun 2012 19:44:11 +0800 Message-ID: Subject: Re: [PATCH 1/1] mx3fb: support pan display with fb_set_var From: Liu Ying To: FlorianSchandinat@gmx.de Cc: lg@denx.de, linux-fbdev@vger.kernel.org, linux-kernel , g.liakhovetski@gmx.de, Sascha Hauer , linux-arm-kernel Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4126 Lines: 121 2012/5/30, Liu Ying : > Users may call FBIOPUT_VSCREENINFO ioctrl to do pan display. > This ioctrl relies on fb_set_var() to do the job. fb_set_var() > calls custom fb_set_par() method and then calls custom > fb_pan_display() method. The current implementation of mx3fb > reinitializes IPU display controller every time the custom > fb_set_par() method is called, which makes the display flash > if fb_set_var() is called to do panning frequently. The custom > fb_pan_display() method checks if the current xoffset and > yoffset are different from previous ones before doing actual > panning, which prevents the panning from happening within the > fb_set_var() context. This patch checks new var info to decide > whether we really need to reinitialize IPU display controller. > We ignore xoffset and yoffset update because it doesn't require > to reinitialize the controller. Users may specify activate field > of var info with FB_ACTIVATE_NOW and FB_ACTIVATE_FORCE to > reinialize the controller by force. Meanwhile, this patch removes > the check in custom fb_pan_display() method mentioned before to > have the panning work within fb_set_var() context. It doesn't > hurt to do panning again if there is no update for xoffset and > yoffset. > > Signed-off-by: Liu Ying > --- > drivers/video/mx3fb.c | 31 +++++++++++++++++++++++++++---- > 1 files changed, 27 insertions(+), 4 deletions(-) > > diff --git a/drivers/video/mx3fb.c b/drivers/video/mx3fb.c > index e3406ab..86daabe 100644 > --- a/drivers/video/mx3fb.c > +++ b/drivers/video/mx3fb.c > @@ -269,6 +269,8 @@ struct mx3fb_info { > struct scatterlist sg[2]; > > u32 sync; /* preserve var->sync flags */ > + > + struct fb_var_screeninfo cur_var; /* current var info */ > }; > > static void mx3fb_dma_done(void *); > @@ -721,6 +723,26 @@ static void mx3fb_dma_done(void *arg) > complete(&mx3_fbi->flip_cmpl); > } > > +static bool fb_need_not_to_set_par(struct fb_info *fbi) > +{ > + struct mx3fb_info *mx3_fbi = fbi->par; > + struct fb_var_screeninfo old_var = mx3_fbi->cur_var; > + struct fb_var_screeninfo new_var = fbi->var; > + > + if ((fbi->var.activate & FB_ACTIVATE_FORCE) && > + (fbi->var.activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) > + return false; > + > + /* > + * Ignore xoffset and yoffset update, > + * because pan display handles this case. > + */ > + old_var.xoffset = new_var.xoffset; > + old_var.yoffset = new_var.yoffset; > + > + return !memcmp(&old_var, &new_var, sizeof(struct fb_var_screeninfo)); > +} > + > static int __set_par(struct fb_info *fbi, bool lock) > { > u32 mem_len; > @@ -732,6 +754,9 @@ static int __set_par(struct fb_info *fbi, bool lock) > struct idmac_video_param *video = &ichan->params.video; > struct scatterlist *sg = mx3_fbi->sg; > > + if (fb_need_not_to_set_par(fbi)) > + return 0; > + > /* Total cleanup */ > if (mx3_fbi->txd) > sdc_disable_channel(mx3_fbi); > @@ -808,6 +833,8 @@ static int __set_par(struct fb_info *fbi, bool lock) > if (mx3_fbi->blank == FB_BLANK_UNBLANK) > sdc_enable_channel(mx3_fbi); > > + mx3_fbi->cur_var = fbi->var; > + > return 0; > } > > @@ -1068,10 +1095,6 @@ static int mx3fb_pan_display(struct fb_var_screeninfo > *var, > return -EINVAL; > } > > - if (fbi->var.xoffset == var->xoffset && > - fbi->var.yoffset == var->yoffset) > - return 0; /* No change, do nothing */ > - > y_bottom = var->yoffset; > > if (!(var->vmode & FB_VMODE_YWRAP)) > -- > 1.7.1 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > The patch is present here for a period of time. Can someone help to review this? Thanks. -- Best Regards, Liu Ying -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/