From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Cochran Subject: Re: [PATCH v4 2/6] input: touchscreen: ti_am335x_tsc: Remove udelay in interrupt handler Date: Sat, 15 Nov 2014 20:27:39 +0100 Message-ID: <20141115192739.GA18766@localhost.localdomain> References: <1415941651-28962-1-git-send-email-vigneshr@ti.com> <1415941651-28962-3-git-send-email-vigneshr@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1415941651-28962-3-git-send-email-vigneshr-l0cyMroinI0@public.gmane.org> Sender: linux-iio-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Vignesh R Cc: Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Benoit Cousson , Tony Lindgren , Russell King , Jonathan Cameron , Hartmut Knaack , Dmitry Torokhov , Lee Jones , Sebastian Andrzej Siewior , Lars-Peter Clausen , Peter Meerwald , Samuel Ortiz , Felipe Balbi , Brad Griffis , Sanjeev Sharma , Paul Gortmaker , Jan Kardell , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-omap@vger.k List-Id: linux-input@vger.kernel.org On Fri, Nov 14, 2014 at 10:37:27AM +0530, Vignesh R wrote: > From: Brad Griffis > > TSC interrupt handler had udelay to avoid reporting of false pen-up > interrupt to user space. This patch implements workaround suggesting in > Advisory 1.0.31 of silicon errata for am335x, thus eliminating udelay > and touchscreen lag. This also improves performance of touchscreen and > eliminates sudden jump of cursor at touch release. I back ported this series onto v3.15.1 in order to try this out on a custom, beaglebone-like board. With this series, the touch is really broken. (I had fixed the pen up problem in a totally different way for a customer, and so I wanted to try out your solution.) I will try to port the board code to a more recent kernel to try your series again. With which kernel version did you test your patches? And which board? Thanks, Richard