From mboxrd@z Thu Jan 1 00:00:00 1970 From: Charles Keepax Subject: [PATCH v2 2/5] gpio: Add new flags to control sleep status of GPIOs Date: Tue, 23 May 2017 15:47:29 +0100 Message-ID: <1495550852-3672-2-git-send-email-ckeepax@opensource.wolfsonmicro.com> References: <1495550852-3672-1-git-send-email-ckeepax@opensource.wolfsonmicro.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from mx0b-001ae601.pphosted.com ([67.231.152.168]:33992 "EHLO mx0b-001ae601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966918AbdEWOqy (ORCPT ); Tue, 23 May 2017 10:46:54 -0400 In-Reply-To: <1495550852-3672-1-git-send-email-ckeepax@opensource.wolfsonmicro.com> Sender: linux-gpio-owner@vger.kernel.org List-Id: linux-gpio@vger.kernel.org To: linus.walleij@linaro.org Cc: lee.jones@linaro.org, robh+dt@kernel.org, mark.rutland@arm.com, linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, patches@opensource.wolfsonmicro.com, frowand.list@gmail.com, ldewangan@nvidia.com Add new flags to allow users to specify that they are not concerned with the status of GPIOs whilst in a sleep/low power state. Signed-off-by: Charles Keepax Acked-by: Rob Herring --- Changes since v1: - Added much more core support for the SLEEP_MAY_LOOSE_VALUE flag - Moved dt-binding new defines down a few lines Rob, I carried your Ack since I assume you only care about the dt-bindings include, which has only had the previous defines moved down a couple of lines. I hope that is ok. Thanks, Charles drivers/gpio/gpiolib-of.c | 3 +++ drivers/gpio/gpiolib.c | 12 ++++++++++++ drivers/gpio/gpiolib.h | 1 + include/dt-bindings/gpio/gpio.h | 4 ++++ include/linux/gpio/driver.h | 3 +++ include/linux/gpio/machine.h | 2 ++ include/linux/of_gpio.h | 1 + 7 files changed, 26 insertions(+) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index b13b7c7..e2abf0e 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -153,6 +153,9 @@ struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, *flags |= GPIO_OPEN_SOURCE; } + if (of_flags & OF_GPIO_SLEEP_MAY_LOOSE_VALUE) + *flags |= GPIO_SLEEP_MAY_LOOSE_VALUE; + return desc; } diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 5db4413..3cdddf4 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -2869,6 +2869,16 @@ bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset) } EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source); +bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset) +{ + if (offset >= chip->ngpio) + return false; + + return !test_bit(FLAG_SLEEP_MAY_LOOSE_VALUE, + &chip->gpiodev->descs[offset].flags); +} +EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent); + /** * gpiod_get_raw_value_cansleep() - return a gpio's raw value * @desc: gpio whose value will be returned @@ -3223,6 +3233,8 @@ static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, set_bit(FLAG_OPEN_DRAIN, &desc->flags); if (lflags & GPIO_OPEN_SOURCE) set_bit(FLAG_OPEN_SOURCE, &desc->flags); + if (lflags & GPIO_SLEEP_MAY_LOOSE_VALUE) + set_bit(FLAG_SLEEP_MAY_LOOSE_VALUE, &desc->flags); /* No particular flag request, return here... */ if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index 2495b7e..f74b8a7 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -190,6 +190,7 @@ struct gpio_desc { #define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ #define FLAG_USED_AS_IRQ 9 /* GPIO is connected to an IRQ */ #define FLAG_IS_HOGGED 11 /* GPIO is hogged */ +#define FLAG_SLEEP_MAY_LOOSE_VALUE 12 /* GPIO may loose value in sleep */ /* Connection label */ const char *label; diff --git a/include/dt-bindings/gpio/gpio.h b/include/dt-bindings/gpio/gpio.h index b4f54da..c507458 100644 --- a/include/dt-bindings/gpio/gpio.h +++ b/include/dt-bindings/gpio/gpio.h @@ -28,4 +28,8 @@ #define GPIO_OPEN_DRAIN (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_DRAIN) #define GPIO_OPEN_SOURCE (GPIO_SINGLE_ENDED | GPIO_LINE_OPEN_SOURCE) +/* Bit 3 express GPIO suspend/resume persistence */ +#define GPIO_SLEEP_MAINTAIN_VALUE 0 +#define GPIO_SLEEP_MAY_LOOSE_VALUE 8 + #endif diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 3935828..af20369 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -213,6 +213,9 @@ bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset); bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset); bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset); +/* Sleep persistence inquiry for drivers */ +bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset); + /* get driver data */ void *gpiochip_get_data(struct gpio_chip *chip); diff --git a/include/linux/gpio/machine.h b/include/linux/gpio/machine.h index c0d712d..13adadf 100644 --- a/include/linux/gpio/machine.h +++ b/include/linux/gpio/machine.h @@ -9,6 +9,8 @@ enum gpio_lookup_flags { GPIO_ACTIVE_LOW = (1 << 0), GPIO_OPEN_DRAIN = (1 << 1), GPIO_OPEN_SOURCE = (1 << 2), + GPIO_SLEEP_MAINTAIN_VALUE = (0 << 3), + GPIO_SLEEP_MAY_LOOSE_VALUE = (1 << 3), }; /** diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h index 1e089d5..ca10f43 100644 --- a/include/linux/of_gpio.h +++ b/include/linux/of_gpio.h @@ -31,6 +31,7 @@ enum of_gpio_flags { OF_GPIO_ACTIVE_LOW = 0x1, OF_GPIO_SINGLE_ENDED = 0x2, OF_GPIO_OPEN_DRAIN = 0x4, + OF_GPIO_SLEEP_MAY_LOOSE_VALUE = 0x8, }; #ifdef CONFIG_OF_GPIO -- 2.1.4