From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033751AbeEXQfO (ORCPT ); Thu, 24 May 2018 12:35:14 -0400 Received: from mail-pf0-f195.google.com ([209.85.192.195]:40077 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031270AbeEXQfL (ORCPT ); Thu, 24 May 2018 12:35:11 -0400 X-Google-Smtp-Source: AB8JxZrGBaYE814Fh4nybA5c5XTVqDbrfUZgWJosBnbrxfMEErBB801KDom2oZmRUYNeDxIptv3yHQ== Date: Thu, 24 May 2018 09:35:07 -0700 From: Dmitry Torokhov To: Sebastian Reichel Cc: Nick Dyer , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Ezequiel Garcia , kernel@collabora.com Subject: Re: [PATCHv2] Input: atmel_mxt_ts - fix reset-gpio for level based irqs Message-ID: <20180524163507.GB177107@dtor-ws> References: <20180420172408.26164-1-sebastian.reichel@collabora.co.uk> <20180423115844.26281-1-sebastian.reichel@collabora.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180423115844.26281-1-sebastian.reichel@collabora.co.uk> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 23, 2018 at 01:58:44PM +0200, Sebastian Reichel wrote: > The current reset-gpio support triggers an interrupt storm on platforms > using the maxtouch with level based interrupt. The Motorola Droid 4, > which I used for some of the tests is not affected, since it uses a edge > based interrupt. > > This change avoids the interrupt storm by enabling the device while its > interrupt is disabled. Afterwards we wait 100ms. This is important for > two reasons: The device is unresponsive for some time (~22ms for > mxt224E) and the CHG (interrupt) line is not working properly for 100ms. > We don't need to wait for any following interrupts, since the following > mxt_initialize() checks for bootloader mode anyways. > > This fixes a boot issue on GE PPD (watchdog kills device due to > interrupt storm) and does not cause regression on Motorola Droid 4. > > Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line") > Signed-off-by: Sebastian Reichel Applied, thank you. > --- > Changes since PATCHv2: > * fix patch description > * use same timeout value for soft and gpio-reset > --- > drivers/input/touchscreen/atmel_mxt_ts.c | 18 +++++++----------- > 1 file changed, 7 insertions(+), 11 deletions(-) > > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c > index 5d9699fe1b55..f97fbb0af020 100644 > --- a/drivers/input/touchscreen/atmel_mxt_ts.c > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c > @@ -194,6 +194,8 @@ enum t100_type { > > /* Delay times */ > #define MXT_BACKUP_TIME 50 /* msec */ > +#define MXT_RESET_GPIO_TIME 20 /* msec */ > +#define MXT_RESET_INVALID_CHG 100 /* msec */ > #define MXT_RESET_TIME 200 /* msec */ > #define MXT_RESET_TIMEOUT 3000 /* msec */ > #define MXT_CRC_TIMEOUT 1000 /* msec */ > @@ -1206,7 +1208,7 @@ static int mxt_soft_reset(struct mxt_data *data) > return ret; > > /* Ignore CHG line for 100ms after reset */ > - msleep(100); > + msleep(MXT_RESET_INVALID_CHG); > > mxt_acquire_irq(data); > > @@ -3167,20 +3169,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id) > return error; > } > > + disable_irq(client->irq); > + > if (data->reset_gpio) { > - data->in_bootloader = true; > - msleep(MXT_RESET_TIME); > - reinit_completion(&data->bl_completion); > + msleep(MXT_RESET_GPIO_TIME); > gpiod_set_value(data->reset_gpio, 1); > - error = mxt_wait_for_completion(data, &data->bl_completion, > - MXT_RESET_TIMEOUT); > - if (error) > - return error; > - data->in_bootloader = false; > + msleep(MXT_RESET_INVALID_CHG); > } > > - disable_irq(client->irq); > - > error = mxt_initialize(data); > if (error) > return error; > -- > 2.17.0 > -- Dmitry