Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751763AbaBIIqU (ORCPT ); Sun, 9 Feb 2014 03:46:20 -0500 Received: from gnurou.org ([207.192.72.5]:35635 "EHLO mail.gnurou.org" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751469AbaBIIqS (ORCPT ); Sun, 9 Feb 2014 03:46:18 -0500 From: Alexandre Courbot To: Linus Walleij , Mika Westerberg , Jean-Jacques Hiblot Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Alexandre Courbot Subject: [PATCH 1/2] gpiolib: add gpiochip_get_desc() driver function Date: Sun, 9 Feb 2014 17:43:54 +0900 Message-Id: <1391935435-29002-1-git-send-email-acourbot@nvidia.com> X-Mailer: git-send-email 1.8.5.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some drivers dealing with a gpio_chip might need to act on its descriptors directly; one example is pinctrl drivers that need to lock a GPIO for being used as IRQ using gpiod_lock_as_irq(). This patch exports a gpiochip_get_desc() function that returns the GPIO descriptor at the requested index. It also sweeps the gpio_to_chip() function out of the consumer interface since any holder of a gpio_chip reference can manipulate its GPIOs way beyond what a consumer should be allowed to do. As a result, gpio_chip is not visible anymore to simple GPIO consumers. Signed-off-by: Alexandre Courbot --- Jean-Jacques, I think you will want to use this function for locking GPIOs in the AT91 pinctrl driver. Mika, we talked about this a while ago already, but here it is finally. Next patch uses it in the GPIO ACPI driver. drivers/gpio/gpiolib.c | 17 +++++++++-------- include/linux/gpio/consumer.h | 8 -------- include/linux/gpio/driver.h | 18 ++++++++++++++++++ 3 files changed, 27 insertions(+), 16 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 50c4922..f60d74b 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -164,16 +164,17 @@ struct gpio_desc *gpio_to_desc(unsigned gpio) EXPORT_SYMBOL_GPL(gpio_to_desc); /** - * Convert an offset on a certain chip to a corresponding descriptor + * Get the GPIO descriptor corresponding to the given hw number for this chip. */ -static struct gpio_desc *gpiochip_offset_to_desc(struct gpio_chip *chip, - unsigned int offset) +struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, + u16 hwnum) { - if (offset >= chip->ngpio) + if (hwnum >= chip->ngpio) return ERR_PTR(-EINVAL); - return &chip->desc[offset]; + return &chip->desc[hwnum]; } +EXPORT_SYMBOL_GPL(gpiochip_get_desc); /** * Convert a GPIO descriptor to the integer namespace. @@ -2161,7 +2162,7 @@ EXPORT_SYMBOL_GPL(gpiod_lock_as_irq); int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset) { - return gpiod_lock_as_irq(gpiochip_offset_to_desc(chip, offset)); + return gpiod_lock_as_irq(gpiochip_get_desc(chip, offset)); } EXPORT_SYMBOL_GPL(gpio_lock_as_irq); @@ -2183,7 +2184,7 @@ EXPORT_SYMBOL_GPL(gpiod_unlock_as_irq); void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) { - return gpiod_unlock_as_irq(gpiochip_offset_to_desc(chip, offset)); + return gpiod_unlock_as_irq(gpiochip_get_desc(chip, offset)); } EXPORT_SYMBOL_GPL(gpio_unlock_as_irq); @@ -2404,7 +2405,7 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, return ERR_PTR(-EINVAL); } - desc = gpiochip_offset_to_desc(chip, p->chip_hwnum); + desc = gpiochip_get_desc(chip, p->chip_hwnum); *flags = p->flags; return desc; diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h index 7a8144f..f6a9cc3 100644 --- a/include/linux/gpio/consumer.h +++ b/include/linux/gpio/consumer.h @@ -5,7 +5,6 @@ #include struct device; -struct gpio_chip; /** * Opaque descriptor for a GPIO. These are obtained using gpiod_get() and are @@ -59,7 +58,6 @@ int gpiod_to_irq(const struct gpio_desc *desc); /* Convert between the old gpio_ and new gpiod_ interfaces */ struct gpio_desc *gpio_to_desc(unsigned gpio); int desc_to_gpio(const struct gpio_desc *desc); -struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc); #else /* CONFIG_GPIOLIB */ @@ -207,12 +205,6 @@ static inline int desc_to_gpio(const struct gpio_desc *desc) WARN_ON(1); return -EINVAL; } -static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) -{ - /* GPIO can never have been requested */ - WARN_ON(1); - return ERR_PTR(-ENODEV); -} #endif /* CONFIG_GPIOLIB */ diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index a3e181e..9fe2836 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -10,6 +10,8 @@ struct of_phandle_args; struct device_node; struct seq_file; +#ifdef CONFIG_GPIOLIB + /** * struct gpio_chip - abstract a GPIO controller * @label: for diagnostics @@ -129,6 +131,11 @@ extern struct gpio_chip *gpiochip_find(void *data, int gpiod_lock_as_irq(struct gpio_desc *desc); void gpiod_unlock_as_irq(struct gpio_desc *desc); +struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc); + +struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, + u16 hwnum); + enum gpio_lookup_flags { GPIO_ACTIVE_HIGH = (0 << 0), GPIO_ACTIVE_LOW = (1 << 0), @@ -183,4 +190,15 @@ struct gpiod_lookup_table { void gpiod_add_lookup_table(struct gpiod_lookup_table *table); +#else /* CONFIG_GPIOLIB */ + +static inline struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) +{ + /* GPIO can never have been requested */ + WARN_ON(1); + return ERR_PTR(-ENODEV); +} + +#endif /* CONFIG_GPIOLIB */ + #endif -- 1.8.5.4 -- 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/