From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Hemanth V" Subject: Re: omap3evm: touchscreen delays on pm branch Date: Fri, 27 Nov 2009 16:04:38 +0530 Message-ID: <040b01ca6f4d$38ac95c0$LocalHost@wipultra793> References: <4B0F9045.6030404@ti.com> <1259312859.19138.4.camel@boson> Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit Return-path: Received: from comal.ext.ti.com ([198.47.26.152]:35923 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754244AbZK0Keg (ORCPT ); Fri, 27 Nov 2009 05:34:36 -0500 Received: from dbdp31.itg.ti.com ([172.24.170.98]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id nARAYdvP004128 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 27 Nov 2009 04:34:41 -0600 Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "Premi, Sanjeev" , "Dasgupta, Romit" Cc: linux-omap@vger.kernel.org ----- Original Message ----- From: "Premi, Sanjeev" To: "Dasgupta, Romit" Cc: Sent: Friday, November 27, 2009 3:20 PM Subject: RE: omap3evm: touchscreen delays on pm branch >> -----Original Message----- >> From: Dasgupta, Romit >> Sent: Friday, November 27, 2009 2:38 PM >> To: Premi, Sanjeev >> Cc: linux-omap@vger.kernel.org >> Subject: RE: omap3evm: touchscreen delays on pm branch >> >> On Fri, 2009-11-27 at 14:11 +0530, Premi, Sanjeev wrote: >> > > -----Original Message----- >> > > From: Dasgupta, Romit >> > > Sent: Friday, November 27, 2009 2:10 PM >> > > To: Premi, Sanjeev >> > > Cc: linux-omap@vger.kernel.org >> > > Subject: Re: omap3evm: touchscreen delays on pm branch >> > > >> > > Premi, Sanjeev wrote: >> > > > Hi, >> > > > >> > > > I am finding the response of touchscreen on the >> omap3evm very slow. >> > > > >> > > > Here is my test: >> > > > On console, I run : watch -n2 "cat /proc/interrupts" >> > > > Then, I tap the touchscreen approximately once per >> second. However, >> > > > (usually) no interrupts are registered. As I increase >> the frequency >> > > > of 'taps' more and more interrupts are registered. But still not >> > > > matching exact taps. >> > > > >> > > > However, when I keep the cpu busy with "cat /dev/zero > >> /dev/null &" >> > > > each tap is recognized. >> > > > >> > > Do you see this even if we don't enable OFF? >> > > >> > Yes. Sleep_while_idle=0; enable_off_mode=0 >> > ~sanjeev >> >> Hopefully you have the same TSC driver. Nevertheless, can you >> please try >> this (just to see if clock domain idling is causing any >> problem or not): > > It is the same driver at SDP3430. I had earlier tried removing > cpuidle altogether and did not see this issue. I too believe that > issue is caused by clocks being going to (auto)idle. > > But then, Hemanth should be seeing the same behavior. Zoom2/Zoom3 use a different touchscreen driver compared to SDP. Its uses Synaptic Touchscreen over I2C.