Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754352AbbHXUYE (ORCPT ); Mon, 24 Aug 2015 16:24:04 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:47142 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751179AbbHXUYB (ORCPT ); Mon, 24 Aug 2015 16:24:01 -0400 Message-ID: <55DB7D4F.4090004@ti.com> Date: Mon, 24 Aug 2015 15:23:43 -0500 From: "Franklin S Cooper Jr." User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 MIME-Version: 1.0 To: Dmitry Torokhov CC: , , , , , , , Subject: Re: [PATCH] Input: edt-ft5x06 - Switch to newer gpio framework References: <1440184112-11061-1-git-send-email-fcooper@ti.com> <20150824194113.GE22442@dtor-ws> <55DB7514.7030009@ti.com> <20150824200126.GF22442@dtor-ws> <55DB7BA4.5010905@ti.com> In-Reply-To: <55DB7BA4.5010905@ti.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5542 Lines: 123 On 08/24/2015 03:16 PM, Franklin S Cooper Jr. wrote: > > On 08/24/2015 03:01 PM, Dmitry Torokhov wrote: >> On Mon, Aug 24, 2015 at 02:48:36PM -0500, Franklin S Cooper Jr. wrote: >>> On 08/24/2015 02:41 PM, Dmitry Torokhov wrote: >>>> On Fri, Aug 21, 2015 at 02:08:32PM -0500, Franklin S Cooper Jr wrote: >>>>> The current/old gpio framework used doesn't properly listen to >>>>> ACTIVE_LOW and ACTIVE_HIGH flags. The newer gpio framework takes into >>>>> account these flags when setting gpio values. >>>>> >>>>> Also use gpiod_set_value_cansleep since wake and reset pins can be >>>>> provided by bus based io expanders. >>>>> >>>>> Signed-off-by: Franklin S Cooper Jr >>>>> --- >>>>> .../bindings/input/touchscreen/edt-ft5x06.txt | 4 +- >>>>> drivers/input/touchscreen/edt-ft5x06.c | 115 +++++++-------------- >>>>> include/linux/input/edt-ft5x06.h | 4 +- >>>>> 3 files changed, 43 insertions(+), 80 deletions(-) >>>>> >>>>> diff --git a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt >>>>> index 76db967..9330d4d 100644 >>>>> --- a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt >>>>> +++ b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt >>>>> @@ -50,6 +50,6 @@ Example: >>>>> pinctrl-0 = <&edt_ft5x06_pins>; >>>>> interrupt-parent = <&gpio2>; >>>>> interrupts = <5 0>; >>>>> - reset-gpios = <&gpio2 6 1>; >>>>> - wake-gpios = <&gpio4 9 0>; >>>>> + reset-gpios = <&gpio2 6 GPIO_ACTIVE_LOW>; >>>>> + wake-gpios = <&gpio4 9 GPIO_ACTIVE_HIGH>; >>>>> }; >>>>> diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c >>>>> index 394b1de..6b128b3 100644 >>>>> --- a/drivers/input/touchscreen/edt-ft5x06.c >>>>> +++ b/drivers/input/touchscreen/edt-ft5x06.c >>>>> @@ -91,9 +91,9 @@ struct edt_ft5x06_ts_data { >>>>> u16 num_x; >>>>> u16 num_y; >>>>> >>>>> - int reset_pin; >>>>> - int irq_pin; >>>>> - int wake_pin; >>>>> + struct gpio_desc *reset_pin; >>>>> + struct gpio_desc *wake_pin; >>>>> + struct gpio_desc *irq_pin; >>>>> >>>>> #if defined(CONFIG_DEBUG_FS) >>>>> struct dentry *debug_dir; >>>>> @@ -755,36 +755,14 @@ edt_ft5x06_ts_teardown_debugfs(struct edt_ft5x06_ts_data *tsdata) >>>>> static int edt_ft5x06_ts_reset(struct i2c_client *client, >>>>> struct edt_ft5x06_ts_data *tsdata) >>>>> { >>>>> - int error; >>>>> - >>>>> - if (gpio_is_valid(tsdata->wake_pin)) { >>>>> - error = devm_gpio_request_one(&client->dev, >>>>> - tsdata->wake_pin, GPIOF_OUT_INIT_LOW, >>>>> - "edt-ft5x06 wake"); >>>>> - if (error) { >>>>> - dev_err(&client->dev, >>>>> - "Failed to request GPIO %d as wake pin, error %d\n", >>>>> - tsdata->wake_pin, error); >>>>> - return error; >>>>> - } >>>>> - >>>>> + if (tsdata->wake_pin) { >>>>> msleep(5); >>>>> - gpio_set_value(tsdata->wake_pin, 1); >>>>> + gpiod_set_value_cansleep(tsdata->wake_pin, 1); >>>>> } >>>>> - if (gpio_is_valid(tsdata->reset_pin)) { >>>>> - /* this pulls reset down, enabling the low active reset */ >>>>> - error = devm_gpio_request_one(&client->dev, >>>>> - tsdata->reset_pin, GPIOF_OUT_INIT_LOW, >>>>> - "edt-ft5x06 reset"); >>>>> - if (error) { >>>>> - dev_err(&client->dev, >>>>> - "Failed to request GPIO %d as reset pin, error %d\n", >>>>> - tsdata->reset_pin, error); >>>>> - return error; >>>>> - } >>>>> >>>>> + if (tsdata->reset_pin) { >>>>> msleep(5); >>>>> - gpio_set_value(tsdata->reset_pin, 1); >>>>> + gpiod_set_value_cansleep(tsdata->reset_pin, 1); >>>> So this leaves the reset pin active. How exactly was this tested? >>> Normally if the output gpio connected to the reset pin is ACTIVE_HIGH then this will take the tsc out of reset since >>> the reset pin is active low. However, I have a board that has an inverter between the gpio and reset pin. So if I leave >>> the gpio as ACTIVE_HIGH then the inverter would cause the reset pin to go low which will keep it in reset. So instead >>> I set the gpio to ACTIVE_LOW which gives me the expected result. >> I do not really care about particular board. Assuming that polarity of >> the GPIO in DTS is specified correctly the effect of: >> >> gpiod_set_value_cansleep(tsdata->reset_pin, 1); >> >> is reset pin being _active_, i.e. the chip is staying in reset state. > Setting the reset pin to 1/high will take the tsc out of reset. Setting the pin to 0/low will put the tsc into reset mode. >> By the way, both reset and wake pins are active low according to the >> data sheet I found. > Your right. Reset and wake are both active low. However, that part of the code is trying to get the tsc out of reset which is > why its setting the value to 1. Setting the pin to 1 was being done even before my patch. > > What has changed was removing the below line which puts the tsc in reset. > > error = devm_gpio_request_one(&client->dev, tsdata->reset_pin, GPIOF_OUT_INIT_LOW,"edt-ft5x06 reset"); > > However, the above line isn't needed since when I request the gpio I already configured it as an output > with a default value of 0. > Sorry accidentally hit reply in this thread instead of reply all. Adding back everyone removed from CC list. >> Thanks. >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/