From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755663AbbESMti (ORCPT ); Tue, 19 May 2015 08:49:38 -0400 Received: from mail-out.m-online.net ([212.18.0.9]:35640 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753886AbbESMtg (ORCPT ); Tue, 19 May 2015 08:49:36 -0400 X-Auth-Info: yKzzA5oEDrsYprGE0GsqaUahcnd0Q42KPCUCMVYMDbw= Date: Tue, 19 May 2015 14:49:22 +0200 From: Anatolij Gustschin To: Evgeniy Dushistov Cc: Dmitry Torokhov , Jingoo Han , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [RFC] ads7846: force driver to work with ads7845 Message-ID: <20150519144922.20768521@crub> In-Reply-To: <20150518125500.GA22524@fifteen> References: <20150518125500.GA22524@fifteen> X-Mailer: Claws Mail 3.8.0 (GTK+ 2.24.10; i686-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 Hi, On Mon, 18 May 2015 15:55:00 +0300 Evgeniy Dushistov wrote: > CC me please, I'm not subscribed to any linux-kernel list. > > Hi, > recently I have ads7845 device connected to my beagleboard, > and I try to use ads7846 to work with it. > But it fails, it show completely wrong x/y. > > But, after I disabled almost all code that related to ads7845 ("== 7845"), > except determination of amount of pressure force, > all start works as expected, > I found such commit: > > >commit 3eac5c7e44f35eb07f0ecb28ce60f15b2dda1932 > >Author: Anatolij Gustschin > >... > >ADS7845 is a controller for 5-wire touch screens and somewhat > >different from 7846. It requires three serial communications to > >accomplish one complete conversion. > >... > > But according to datasheets: > http://www.ti.com/lit/ds/symlink/ads7846.pdf > http://www.ti.com/lit/ds/symlink/ads7845.pdf > > ads7845(page 8) and ads7846 (page 12) have > identical digital interfaces, I attach quotes > from them in text from to this email. > > So why spi negotiation for ads7845 require special code, > except > >Z1-/Z2- position measurement > > Was this commit tested? May be you test > in some special mode, like 15 vs 16 bits? this was tested, but if I remember correctly, on some ppc board were multi-segment SPI transfers didn't work (SPI chip-select disabled by controller after first SPI command byte). I do not know any more if it was the only reason for this ads7845 specific handling in my commit and unfortunately I do not have this board to check it again. > Here is working for me patch (it against 3.16, > but applied to Linus's git master also). > > ads7846: fix to force ads7846 driver works with ads7845 > device Then can you please first revert my patch and then add the only code that is needed to work with ads7845 ? After this you can squash both parts to a single commit and submit a clean patch. Thanks, Anatolij > Signed-off-by: Evgneiy A. Dushistov > --- > drivers/input/touchscreen/ads7846.c | 21 +++++++++++---------- > 1 file changed, 11 insertions(+), 10 deletions(-) > > diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c > index da201b8..27f4796 100644 > --- a/drivers/input/touchscreen/ads7846.c > +++ b/drivers/input/touchscreen/ads7846.c > @@ -17,6 +17,9 @@ > * it under the terms of the GNU General Public License version 2 as > * published by the Free Software Foundation. > */ > +#define VERBOSE_DEBUG > +#define DEBUG > + > #include > #include > #include > @@ -671,14 +674,14 @@ static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m) > struct spi_transfer *t = > list_entry(m->transfers.prev, struct spi_transfer, transfer_list); > > - if (ts->model == 7845) { > + if (0/*ts->model == 7845*/) { > return be16_to_cpup((__be16 *)&(((char*)t->rx_buf)[1])) >> 3; > } else { > /* > * adjust: on-wire is a must-ignore bit, a BE12 value, then > * padding; built from two 8 bit values written msb-first. > */ > - return be16_to_cpup((__be16 *)t->rx_buf) >> 3; > + return (be16_to_cpup((__be16 *)t->rx_buf) & 0x7fff) >> 3; > } > } > > @@ -755,14 +758,12 @@ static void ads7846_report_state(struct ads7846 *ts) > * from on-the-wire format as part of debouncing to get stable > * readings. > */ > + x = packet->tc.x; > + y = packet->tc.y; > if (ts->model == 7845) { > - x = *(u16 *)packet->tc.x_buf; > - y = *(u16 *)packet->tc.y_buf; > z1 = 0; > z2 = 0; > } else { > - x = packet->tc.x; > - y = packet->tc.y; > z1 = packet->tc.z1; > z2 = packet->tc.z2; > } > @@ -995,7 +996,7 @@ static void ads7846_setup_spi_msg(struct ads7846 *ts, > spi_message_init(m); > m->context = ts; > > - if (ts->model == 7845) { > + if (0/*ts->model == 7845*/) { > packet->read_y_cmd[0] = READ_Y(vref); > packet->read_y_cmd[1] = 0; > packet->read_y_cmd[2] = 0; > @@ -1040,7 +1041,7 @@ static void ads7846_setup_spi_msg(struct ads7846 *ts, > spi_message_init(m); > m->context = ts; > > - if (ts->model == 7845) { > + if (0/*ts->model == 7845*/) { > x++; > packet->read_x_cmd[0] = READ_X(vref); > packet->read_x_cmd[1] = 0; > @@ -1149,7 +1150,7 @@ static void ads7846_setup_spi_msg(struct ads7846 *ts, > spi_message_init(m); > m->context = ts; > > - if (ts->model == 7845) { > + if (0/*ts->model == 7845*/) { > x++; > packet->pwrdown_cmd[0] = PWRDOWN; > packet->pwrdown_cmd[1] = 0; > @@ -1408,7 +1409,7 @@ static int ads7846_probe(struct spi_device *spi) > * Take a first sample, leaving nPENIRQ active and vREF off; avoid > * the touchscreen, in case it's not connected. > */ > - if (ts->model == 7845) > + if (0/*ts->model == 7845*/) > ads7845_read12_ser(&spi->dev, PWRDOWN); > else > (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux));