From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pf0-x243.google.com ([2607:f8b0:400e:c00::243]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1dCpCZ-0008T2-N7 for barebox@lists.infradead.org; Mon, 22 May 2017 15:24:57 +0000 Received: by mail-pf0-x243.google.com with SMTP id f27so20740210pfe.0 for ; Mon, 22 May 2017 08:24:36 -0700 (PDT) From: Andrey Smirnov Date: Mon, 22 May 2017 08:24:18 -0700 Message-Id: <20170522152420.14443-2-andrew.smirnov@gmail.com> In-Reply-To: <20170522152420.14443-1-andrew.smirnov@gmail.com> References: <20170522152420.14443-1-andrew.smirnov@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 2/4] gpiolib: Add code to support "active low" GPIOs To: barebox@lists.infradead.org Cc: Andrey Smirnov , Nikita Yushchenko , cphealy@gmail.com So far this particular aspect of various DT-bindings has been handled on a per-driver basis. With this change, hopefully, we'll have a single place to handle necessary logic inversions and eventually would be able to migrate existing users as well as avoiding adding redundant code to new drivers. Cc: cphealy@gmail.com Cc: Nikita Yushchenko Signed-off-by: Andrey Smirnov --- drivers/gpio/gpiolib.c | 37 +++++++++++++++++++++++++++++++------ include/gpio.h | 3 +++ 2 files changed, 34 insertions(+), 6 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 1f57c76..9e9df355 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -13,6 +13,7 @@ static LIST_HEAD(chip_list); struct gpio_info { struct gpio_chip *chip; bool requested; + bool active_low; char *label; }; @@ -45,6 +46,15 @@ static struct gpio_info *gpio_to_desc(unsigned gpio) return NULL; } +static int gpio_adjust_value(struct gpio_info *gi, + int value) +{ + if (value < 0) + return value; + + return !!value ^ gi->active_low; +} + int gpio_request(unsigned gpio, const char *label) { struct gpio_info *gi = gpio_to_desc(gpio); @@ -69,6 +79,7 @@ int gpio_request(unsigned gpio, const char *label) } gi->requested = true; + gi->active_low = false; gi->label = xstrdup(label); done: @@ -93,6 +104,7 @@ void gpio_free(unsigned gpio) gi->chip->ops->free(gi->chip, gpio - gi->chip->base); gi->requested = false; + gi->active_low = false; free(gi->label); gi->label = NULL; } @@ -111,6 +123,11 @@ int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) if (err) return err; + if (flags & GPIOF_ACTIVE_LOW) { + struct gpio_info *gi = gpio_to_desc(gpio); + gi->active_low = true; + } + if (flags & GPIOF_DIR_IN) err = gpio_direction_input(gpio); else @@ -173,8 +190,10 @@ void gpio_set_value(unsigned gpio, int value) if (gpio_ensure_requested(gi, gpio)) return; - if (gi->chip->ops->set) - gi->chip->ops->set(gi->chip, gpio - gi->chip->base, value); + if (gi->chip->ops->set) { + gi->chip->ops->set(gi->chip, gpio - gi->chip->base, + gpio_adjust_value(gi, value)); + } } EXPORT_SYMBOL(gpio_set_value); @@ -192,7 +211,10 @@ int gpio_get_value(unsigned gpio) if (!gi->chip->ops->get) return -ENOSYS; - return gi->chip->ops->get(gi->chip, gpio - gi->chip->base); + + ret = gi->chip->ops->get(gi->chip, gpio - gi->chip->base); + + return gpio_adjust_value(gi, ret); } EXPORT_SYMBOL(gpio_get_value); @@ -211,7 +233,7 @@ int gpio_direction_output(unsigned gpio, int value) if (!gi->chip->ops->direction_output) return -ENOSYS; return gi->chip->ops->direction_output(gi->chip, gpio - gi->chip->base, - value); + gpio_adjust_value(gi, value)); } EXPORT_SYMBOL(gpio_direction_output); @@ -229,7 +251,10 @@ int gpio_direction_input(unsigned gpio) if (!gi->chip->ops->direction_input) return -ENOSYS; - return gi->chip->ops->direction_input(gi->chip, gpio - gi->chip->base); + + ret = gi->chip->ops->direction_input(gi->chip, gpio - gi->chip->base); + + return gpio_adjust_value(gi, ret); } EXPORT_SYMBOL(gpio_direction_input); @@ -334,7 +359,7 @@ static int do_gpiolib(int argc, char *argv[]) printf(" GPIO %*d: %*s %*s %*s %s\n", 4, i, 3, (dir < 0) ? "unk" : ((dir == GPIOF_DIR_IN) ? "in" : "out"), 3, (val < 0) ? "unk" : ((val == 0) ? "lo" : "hi"), - 9, gi->requested ? "true" : "false", + 12, gi->requested ? (gi->active_low ? "active low" : "true") : "false", (gi->requested && gi->label) ? gi->label : ""); } diff --git a/include/gpio.h b/include/gpio.h index 7b3f512..9432543 100644 --- a/include/gpio.h +++ b/include/gpio.h @@ -41,6 +41,9 @@ static inline int gpio_is_valid(int gpio) #define GPIOF_INIT_LOW (0 << 1) #define GPIOF_INIT_HIGH (1 << 1) +#define GPIOF_ACTIVE_HIGH (0 << 2) +#define GPIOF_ACTIVE_LOW (1 << 2) + #define GPIOF_IN (GPIOF_DIR_IN) #define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW) #define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH) -- 2.9.3 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox