From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762980AbYESXBH (ORCPT ); Mon, 19 May 2008 19:01:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755009AbYESXAz (ORCPT ); Mon, 19 May 2008 19:00:55 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:45841 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752853AbYESXAy (ORCPT ); Mon, 19 May 2008 19:00:54 -0400 Date: Mon, 19 May 2008 16:00:06 -0700 From: Andrew Morton To: Nicolas Ferre Cc: linux-fbdev-devel@lists.sourceforge.net, adaplas@gmail.com, hskinnemoen@atmel.com, linux@maxim.org.za, linux-kernel@vger.kernel.org Subject: Re: [PATCH] atmel_lcdfb: FIFO underflow management Message-Id: <20080519160006.12a30e71.akpm@linux-foundation.org> In-Reply-To: <482D7F44.7040404@atmel.com> References: <482D7F44.7040404@atmel.com> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 16 May 2008 14:34:12 +0200 Nicolas Ferre wrote: > Manage atmel_lcdfb FIFO underflow > > Resetting the LCD and DMA allows to fix screen shifting after a > FIFO underflow. It follows reset sequence from errata > "LCD Screen Shifting After a Reset". > This looks like 2.6.26-worthy bugfix to me? But as commonly happens, that isn't terribly clear. > + if (status & ATMEL_LCDC_UFLWI) { > + dev_warn(info->device, "FIFO underflow %#x\n", status); > + /* reset DMA and FIFO to avoid screen shifting */ > + schedule_work(&sinfo->task); > + } > + lcdc_writel(sinfo, ATMEL_LCDC_ICR, status); > return IRQ_HANDLED; > } Shouldn't there be a cancel_work_sync() in atmel_lcdfb_exit()? > + /* Initialize bottom half workqueue */ Well. "bottom half" is an ancient term for softirqs, not for the new-fangled process-context callbacks.