From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-out.m-online.net ([212.18.0.9]:60410 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752856Ab3IWKga convert rfc822-to-8bit (ORCPT ); Mon, 23 Sep 2013 06:36:30 -0400 From: Marek Vasut To: =?iso-8859-1?q?J=FCrgen_Beisert?= Subject: Re: [PATCHv5] staging/iio/adc: change the MXS touchscreen driver implementation Date: Mon, 23 Sep 2013 12:36:27 +0200 Cc: linux-arm-kernel@lists.infradead.org, linux-iio@vger.kernel.org, devel@driverdev.osuosl.org, fabio.estevam@freescale.com, jic23@cam.ac.uk, Lothar =?iso-8859-1?q?Wa=DFmann?= References: <1379593369-22010-1-git-send-email-jbe@pengutronix.de> <201309230955.58828.jbe@pengutronix.de> <201309231235.56309.jbe@pengutronix.de> In-Reply-To: <201309231235.56309.jbe@pengutronix.de> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Message-Id: <201309231236.27554.marex@denx.de> Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org Dear Jürgen Beisert, > Hi Marek, > > On Monday 23 September 2013 09:55:58 Jürgen Beisert wrote: > > On Monday 23 September 2013 01:55:04 Marek Vasut wrote: > > > > The following series replaces the current busy loop touchscreen > > > > implementation for i.MX28/i.MX23 SoCs by a fully interrupt driven > > > > implementation. > > > > > > > > Since i.MX23 and i.MX28 silicon differs, the existing implementation > > > > can be used for the i.MX28 SoC only. > > > > > > > > So, the first two patches of this series move the i.MX28 specific > > > > definitions out of the way. The third patch simplifies the register > > > > access to make it easier to add the i.MX23 support. Then the i.MX23 > > > > specific definitions are added, also the code to distinguish both > > > > SoCs at run-time. Up to here the existing touchscreen driver will > > > > now run on an i.MX23 Soc as well. > > > > > > > > When the i.MX23 SoC is running from battery it seems not to be a good > > > > idea to run a busy loop to detect touches and their location. The > > > > fourth patch adds a fully interrupt driven implementation which makes > > > > use of the built-in delay and multiple sample features of the > > > > touchscreen controller. This will reduce the interrupt load to a > > > > minimum. > > > > > > > > The next to last patch in this series just removes the existing busy > > > > loop implementation. > > > > > > > > The last patch adds a devicetree bindings proposal (to be discussed). > > > > > > > > Some restrictions/questions: > > > > > > > > - the touchscreen part is yet tested on i.MX23 SoC only > > > > - has someone a good idea how to implement a reliable pressure > > > > measurement if the resistances of the touchscreen's plates are > > > > unknown? > > > > > > > > Changes since v4: > > > > > > > > - honor Jonathan's comments about function names > > > > - honor Dmitry's comments about workqueue canceling and interrupts > > > > - adding devicetree bindings proposal > > > > > > > > Changes since v3: > > > > > > > > - split adding register access functions and i.MX23 support into two > > > > patches > > > > > > > > Changes since v2: > > > > > > > > - useless debug output removed > > > > > > > > Changes since v1: > > > > > > > > - adding register access functions to make the existing code more > > > > readable - adding some functions to distinguish the SoCs at run-time > > > > to avoid if-else contructs whenever differences in the register > > > > layout between i.MX23 and i.MX28 must be handled > > > > > > Just tested this on M28EVK, the touchscreen is dead. I do not get any > > > touch events when I use ts_calibrate and when I hd /dev/input/eventX , > > > I get nothing either. > > > > > > Right now, I'm somehow on a tight schedule, but I'd like to see this > > > resolved ASAP. Do you have any hint for me ? > > > > Seems the very first touch detection does not work. A colleague just told > > me, we have an i.MX28 based hardware here and maybe a touchscreen from a > > different platform which maybe can be used with the i.MX28 platform. Stay > > tuned... > > I also found an MX28EVK with a touchscreen here and: yes it does not work > with the modified driver. But now I'm confused, because of Lothar's > statement about the TX28 platform. > > @Lothar: What kernel revision did you use? I had to go back to 3.9 to get a > working kernel on the MX28EVK. More recent vanilla kernels stop working > (MMC and network fail here). Can you fix the SD and Network or at least show the fail log ? btw. I use 3.12-rc1 (next/master) to test the touchscreen on M28EVK. I don't have the LCD module attached to MX28EVK, so I can't test there. Best regards, Marek Vasut From mboxrd@z Thu Jan 1 00:00:00 1970 From: marex@denx.de (Marek Vasut) Date: Mon, 23 Sep 2013 12:36:27 +0200 Subject: [PATCHv5] staging/iio/adc: change the MXS touchscreen driver implementation In-Reply-To: <201309231235.56309.jbe@pengutronix.de> References: <1379593369-22010-1-git-send-email-jbe@pengutronix.de> <201309230955.58828.jbe@pengutronix.de> <201309231235.56309.jbe@pengutronix.de> Message-ID: <201309231236.27554.marex@denx.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Dear J?rgen Beisert, > Hi Marek, > > On Monday 23 September 2013 09:55:58 J?rgen Beisert wrote: > > On Monday 23 September 2013 01:55:04 Marek Vasut wrote: > > > > The following series replaces the current busy loop touchscreen > > > > implementation for i.MX28/i.MX23 SoCs by a fully interrupt driven > > > > implementation. > > > > > > > > Since i.MX23 and i.MX28 silicon differs, the existing implementation > > > > can be used for the i.MX28 SoC only. > > > > > > > > So, the first two patches of this series move the i.MX28 specific > > > > definitions out of the way. The third patch simplifies the register > > > > access to make it easier to add the i.MX23 support. Then the i.MX23 > > > > specific definitions are added, also the code to distinguish both > > > > SoCs at run-time. Up to here the existing touchscreen driver will > > > > now run on an i.MX23 Soc as well. > > > > > > > > When the i.MX23 SoC is running from battery it seems not to be a good > > > > idea to run a busy loop to detect touches and their location. The > > > > fourth patch adds a fully interrupt driven implementation which makes > > > > use of the built-in delay and multiple sample features of the > > > > touchscreen controller. This will reduce the interrupt load to a > > > > minimum. > > > > > > > > The next to last patch in this series just removes the existing busy > > > > loop implementation. > > > > > > > > The last patch adds a devicetree bindings proposal (to be discussed). > > > > > > > > Some restrictions/questions: > > > > > > > > - the touchscreen part is yet tested on i.MX23 SoC only > > > > - has someone a good idea how to implement a reliable pressure > > > > measurement if the resistances of the touchscreen's plates are > > > > unknown? > > > > > > > > Changes since v4: > > > > > > > > - honor Jonathan's comments about function names > > > > - honor Dmitry's comments about workqueue canceling and interrupts > > > > - adding devicetree bindings proposal > > > > > > > > Changes since v3: > > > > > > > > - split adding register access functions and i.MX23 support into two > > > > patches > > > > > > > > Changes since v2: > > > > > > > > - useless debug output removed > > > > > > > > Changes since v1: > > > > > > > > - adding register access functions to make the existing code more > > > > readable - adding some functions to distinguish the SoCs at run-time > > > > to avoid if-else contructs whenever differences in the register > > > > layout between i.MX23 and i.MX28 must be handled > > > > > > Just tested this on M28EVK, the touchscreen is dead. I do not get any > > > touch events when I use ts_calibrate and when I hd /dev/input/eventX , > > > I get nothing either. > > > > > > Right now, I'm somehow on a tight schedule, but I'd like to see this > > > resolved ASAP. Do you have any hint for me ? > > > > Seems the very first touch detection does not work. A colleague just told > > me, we have an i.MX28 based hardware here and maybe a touchscreen from a > > different platform which maybe can be used with the i.MX28 platform. Stay > > tuned... > > I also found an MX28EVK with a touchscreen here and: yes it does not work > with the modified driver. But now I'm confused, because of Lothar's > statement about the TX28 platform. > > @Lothar: What kernel revision did you use? I had to go back to 3.9 to get a > working kernel on the MX28EVK. More recent vanilla kernels stop working > (MMC and network fail here). Can you fix the SD and Network or at least show the fail log ? btw. I use 3.12-rc1 (next/master) to test the touchscreen on M28EVK. I don't have the LCD module attached to MX28EVK, so I can't test there. Best regards, Marek Vasut