[v1,2/2] gpiolib: Up to date the kernel documentation

Message ID	20240326181247.1419138-3-andriy.shevchenko@linux.intel.com (mailing list archive)
State	Handled Elsewhere, archived
Headers	show Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 338FD129A81; Tue, 26 Mar 2024 18:12:56 +0000 (UTC) From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>, Bartosz Golaszewski <bartosz.golaszewski@linaro.org>, Kent Gibson <warthog618@gmail.com>, linux-gpio@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Mika Westerberg <mika.westerberg@linux.intel.com>, Linus Walleij <linus.walleij@linaro.org>, Bartosz Golaszewski <brgl@bgdev.pl> Subject: [PATCH v1 2/2] gpiolib: Up to date the kernel documentation Date: Tue, 26 Mar 2024 20:11:21 +0200 Message-ID: <20240326181247.1419138-3-andriy.shevchenko@linux.intel.com> In-Reply-To: <20240326181247.1419138-1-andriy.shevchenko@linux.intel.com> References: <20240326181247.1419138-1-andriy.shevchenko@linux.intel.com> Precedence: bulk MIME-Version: 1.0 Content-Transfer-Encoding: 8bit
Series	gpiolib: in-kernel documentation updates \| expand [v1,0/2] gpiolib: in-kernel documentation updates [v1,1/2] gpiolib: Do not mention legacy GPIOF_* in the code [v1,2/2] gpiolib: Up to date the kernel documentation

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 7f140df40f35..dfcfa23e7a59 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -136,8 +136,12 @@ static int acpi_gpiochip_find(struct gpio_chip *gc, const void *data) * @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1") * @pin: ACPI GPIO pin number (0-based, controller-relative) * - * Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR - * error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO + * Returns: + * GPIO descriptor to use with Linux generic GPIO API. + * If the GPIO cannot be translated or there is an error an ERR_PTR is + * returned. + * + * Specifically returns -EPROBE_DEFER if the referenced GPIO * controller does not have GPIO chip registered at the moment. This is to * support probe deferral. */ @@ -156,7 +160,7 @@ static struct gpio_desc *acpi_get_gpiod(char *path, unsigned int pin) return ERR_PTR(-EPROBE_DEFER); /* - * FIXME: keep track of the reference to the GPIO device somehow + * FIXME: Keep track of the reference to the GPIO device somehow * instead of putting it here. */ return gpio_device_get_desc(gdev, pin); @@ -203,10 +207,12 @@ bool acpi_gpio_get_irq_resource(struct acpi_resource *ares, EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource); /** - * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GPIO - * I/O resource or return False if not. + * acpi_gpio_get_io_resource - Fetch details of an ACPI resource if it is a GpioIo resource * @ares: Pointer to the ACPI resource to fetch * @agpio: Pointer to a &struct acpi_resource_gpio to store the output pointer + * + * Returns: + * true if GpioIo resource is found, false otherwise. */ bool acpi_gpio_get_io_resource(struct acpi_resource *ares, struct acpi_resource_gpio **agpio) @@ -487,7 +493,7 @@ static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares, } /** - * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events + * acpi_gpiochip_request_interrupts() - Register isr for GPIO chip ACPI events * @chip: GPIO chip * * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are @@ -664,7 +670,7 @@ __acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update) * Check if caller supplied incompatible GPIO initialization * flags. * - * Return %-EINVAL to notify that firmware has different + * Return -EINVAL to notify that firmware has different * settings and we are going to use them. */ if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) || @@ -764,7 +770,7 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data) /* * Polarity and triggering are only specified for GpioInt * resource. - * Note: we expect here: + * NOTE: We expect here: * - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW * - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH */ @@ -847,22 +853,24 @@ static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode, * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources * @adev: pointer to a ACPI device to get GPIO from * @propname: Property name of the GPIO (optional) - * @index: index of GpioIo/GpioInt resource (starting from %0) + * @index: index of GpioIo/GpioInt resource (starting from 0) * @info: info pointer to fill in (optional) * * Function goes through ACPI resources for @adev and based on @index looks * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor, * and returns it. @index matches GpioIo/GpioInt resources only so if there - * are total %3 GPIO resources, the index goes from %0 to %2. + * are total 3 GPIO resources, the index goes from 0 to 2. * * If @propname is specified the GPIO is looked using device property. In * that case @index is used to select the GPIO entry in the property value * (in case of multiple). * - * If the GPIO cannot be translated or there is an error, an ERR_PTR is + * Returns: + * GPIO descriptor to use with Linux generic GPIO API. + * If the GPIO cannot be translated or there is an error an ERR_PTR is * returned. * - * Note: if the GPIO resource has multiple entries in the pin list, this + * NOTE: If the GPIO resource has multiple entries in the pin list, this * function only returns the first. */ static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, @@ -903,13 +911,15 @@ static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, * acpi_get_gpiod_from_data() - get a GPIO descriptor from ACPI data node * @fwnode: pointer to an ACPI firmware node to get the GPIO information from * @propname: Property name of the GPIO - * @index: index of GpioIo/GpioInt resource (starting from %0) + * @index: index of GpioIo/GpioInt resource (starting from 0) * @info: info pointer to fill in (optional) * * This function uses the property-based GPIO lookup to get to the GPIO * resource with the relevant information from a data-only ACPI firmware node * and uses that to obtain the GPIO descriptor to return. * + * Returns: + * GPIO descriptor to use with Linux generic GPIO API. * If the GPIO cannot be translated or there is an error an ERR_PTR is * returned. */ @@ -1007,7 +1017,7 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode, * acpi_dev_gpio_irq_wake_get_by() - Find GpioInt and translate it to Linux IRQ number * @adev: pointer to a ACPI device to get IRQ from * @name: optional name of GpioInt resource - * @index: index of GpioInt resource (starting from %0) + * @index: index of GpioInt resource (starting from 0) * @wake_capable: Set to true if the IRQ is wake capable * * If the device has one or more GpioInt resources, this function can be @@ -1023,7 +1033,8 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode, * The GPIO is considered wake capable if the GpioInt resource specifies * SharedAndWake or ExclusiveAndWake. * - * Return: Linux IRQ number (> %0) on success, negative errno on failure. + * Returns: + * Linux IRQ number (> 0) on success, negative errno on failure. */ int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *name, int index, bool *wake_capable) @@ -1406,8 +1417,8 @@ static int acpi_find_gpio_count(struct acpi_resource *ares, void *data) * @fwnode: firmware node of the GPIO consumer * @con_id: function within the GPIO consumer * - * Return: - * The number of GPIOs associated with a firmware node / function or %-ENOENT, + * Returns: + * The number of GPIOs associated with a firmware node / function or -ENOENT, * if no GPIO has been assigned to the requested function. */ int acpi_gpio_count(const struct fwnode_handle *fwnode, const char *con_id) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index f384fa278764..b4369a8b4381 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -54,7 +54,8 @@ static_assert(IS_ALIGNED(sizeof(struct gpio_v2_line_info_changed), 8)); static_assert(IS_ALIGNED(sizeof(struct gpio_v2_line_event), 8)); static_assert(IS_ALIGNED(sizeof(struct gpio_v2_line_values), 8)); -/* Character device interface to GPIO. +/* + * Character device interface to GPIO. * * The GPIO character device, /dev/gpiochipN, provides userspace an * interface to gpiolib GPIOs via ioctl()s. @@ -531,7 +532,7 @@ static DEFINE_SPINLOCK(supinfo_lock); * @event_buffer_size: the number of elements allocated in @events * @events: KFIFO for the GPIO events * @seqno: the sequence number for edge events generated on all lines in - * this line request. Note that this is not used when @num_lines is 1, as + * this line request. NOTE: This is not used when @num_lines is 1, as * the line_seqno is then the same and is cheaper to calculate. * @config_mutex: mutex for serializing ioctl() calls to ensure consistency * of configuration, particularly multi-step accesses to desc flags and @@ -2684,7 +2685,9 @@ static ssize_t lineinfo_watch_read(struct file *file, char __user *buf, * gpio_chrdev_open() - open the chardev for ioctl operations * @inode: inode for this chardev * @file: file struct for storing private data - * Returns 0 on success + * + * Returns: + * 0 on success, or negative errno on failure. */ static int gpio_chrdev_open(struct inode *inode, struct file *file) { @@ -2695,7 +2698,7 @@ static int gpio_chrdev_open(struct inode *inode, struct file *file) guard(srcu)(&gdev->srcu); - /* Fail on open if the backing gpiochip is gone */ + /* Fail on open if the backing GPIO chip is gone */ if (!rcu_access_pointer(gdev->chip)) return -ENODEV; @@ -2750,7 +2753,9 @@ static int gpio_chrdev_open(struct inode *inode, struct file *file) * gpio_chrdev_release() - close chardev after ioctl operations * @inode: inode for this chardev * @file: file struct for storing private data - * Returns 0 on success + * + * Returns: + * 0 on success, or negative errno on failure. */ static int gpio_chrdev_release(struct inode *inode, struct file *file) { diff --git a/drivers/gpio/gpiolib-devres.c b/drivers/gpio/gpiolib-devres.c index 4987e62dcb3d..20e3eae785b6 100644 --- a/drivers/gpio/gpiolib-devres.c +++ b/drivers/gpio/gpiolib-devres.c @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* - * devres.c - managed gpio resources + * Managed GPIO resources. * This file is based on kernel/irq/devres.c * * Copyright (c) 2011 John Crispin <john@phrozen.org> @@ -52,6 +52,11 @@ static int devm_gpiod_match_array(struct device *dev, void *res, void *data) * Managed gpiod_get(). GPIO descriptors returned from this function are * automatically disposed on driver detach. See gpiod_get() for detailed * information about behavior and return values. + * + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device + * dev, -ENOENT if no GPIO has been assigned to the requested function, or + * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check devm_gpiod_get(struct device *dev, const char *con_id, @@ -70,6 +75,11 @@ EXPORT_SYMBOL_GPL(devm_gpiod_get); * Managed gpiod_get_optional(). GPIO descriptors returned from this function * are automatically disposed on driver detach. See gpiod_get_optional() for * detailed information about behavior and return values. + * + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device + * dev, NULL if no GPIO has been assigned to the requested function, or + * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev, const char *con_id, @@ -89,6 +99,11 @@ EXPORT_SYMBOL_GPL(devm_gpiod_get_optional); * Managed gpiod_get_index(). GPIO descriptors returned from this function are * automatically disposed on driver detach. See gpiod_get_index() for detailed * information about behavior and return values. + * + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device + * dev, -ENOENT if no GPIO has been assigned to the requested function, or + * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev, const char *con_id, @@ -141,8 +156,10 @@ EXPORT_SYMBOL_GPL(devm_gpiod_get_index); * GPIO descriptors returned from this function are automatically disposed on * driver detach. * - * On successful request the GPIO pin is configured in accordance with - * provided @flags. + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device + * dev, -ENOENT if no GPIO has been assigned to the requested function, or + * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev, struct fwnode_handle *fwnode, @@ -182,6 +199,11 @@ EXPORT_SYMBOL_GPL(devm_fwnode_gpiod_get_index); * function are automatically disposed on driver detach. See * gpiod_get_index_optional() for detailed information about behavior and * return values. + * + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device + * dev, NULL if no GPIO has been assigned to the requested function, or + * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev, const char *con_id, @@ -207,6 +229,12 @@ EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional); * Managed gpiod_get_array(). GPIO descriptors returned from this function are * automatically disposed on driver detach. See gpiod_get_array() for detailed * information about behavior and return values. + * + * Returns: + * The GPIO descriptors corresponding to the function @con_id of device + * dev, -ENOENT if no GPIO has been assigned to the requested function, + * or another IS_ERR() code if an error occurred while trying to acquire + * the GPIOs. */ struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev, const char *con_id, @@ -243,6 +271,12 @@ EXPORT_SYMBOL_GPL(devm_gpiod_get_array); * function are automatically disposed on driver detach. * See gpiod_get_array_optional() for detailed information about behavior and * return values. + * + * Returns: + * The GPIO descriptors corresponding to the function @con_id of device + * dev, NULL if no GPIO has been assigned to the requested function, + * or another IS_ERR() code if an error occurred while trying to acquire + * the GPIOs. */ struct gpio_descs *__must_check devm_gpiod_get_array_optional(struct device *dev, const char *con_id, @@ -275,7 +309,7 @@ void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) EXPORT_SYMBOL_GPL(devm_gpiod_put); /** - * devm_gpiod_unhinge - Remove resource management from a gpio descriptor + * devm_gpiod_unhinge - Remove resource management from a GPIO descriptor * @dev: GPIO consumer * @desc: GPIO descriptor to remove resource management from * @@ -283,7 +317,6 @@ EXPORT_SYMBOL_GPL(devm_gpiod_put); * you want to hand over lifecycle management of a descriptor to another * mechanism. */ - void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc) { int ret; @@ -328,15 +361,20 @@ static void devm_gpio_release(struct device *dev, void *res) } /** - * devm_gpio_request - request a GPIO for a managed device - * @dev: device to request the GPIO for - * @gpio: GPIO to allocate - * @label: the name of the requested GPIO + * devm_gpio_request - request a GPIO for a managed device + * @dev: device to request the GPIO for + * @gpio: GPIO to allocate + * @label: the name of the requested GPIO * - * Except for the extra @dev argument, this function takes the - * same arguments and performs the same function as - * gpio_request(). GPIOs requested with this function will be - * automatically freed on driver detach. + * Except for the extra @dev argument, this function takes the + * same arguments and performs the same function as gpio_request(). + * GPIOs requested with this function will be automatically freed + * on driver detach. + * + * **DEPRECATED** This function is deprecated and must not be used in new code. + * + * Returns: + * 0 on success, or negative errno on failure. */ int devm_gpio_request(struct device *dev, unsigned gpio, const char *label) { @@ -361,11 +399,16 @@ int devm_gpio_request(struct device *dev, unsigned gpio, const char *label) EXPORT_SYMBOL_GPL(devm_gpio_request); /** - * devm_gpio_request_one - request a single GPIO with initial setup - * @dev: device to request for - * @gpio: the GPIO number - * @flags: GPIO configuration as specified by GPIOF_* - * @label: a literal description string of this GPIO + * devm_gpio_request_one - request a single GPIO with initial setup + * @dev: device to request for + * @gpio: the GPIO number + * @flags: GPIO configuration as specified by GPIOF_* + * @label: a literal description string of this GPIO + * + * **DEPRECATED** This function is deprecated and must not be used in new code. + * + * Returns: + * 0 on success, or negative errno on failure. */ int devm_gpio_request_one(struct device *dev, unsigned gpio, unsigned long flags, const char *label) @@ -399,15 +442,15 @@ static void devm_gpio_chip_release(void *data) /** * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key() - * @dev: pointer to the device that gpio_chip belongs to. + * @dev: pointer to the device that GPIO chip belongs to. * @gc: the GPIO chip to register * @data: driver-private data associated with this chip * @lock_key: lockdep class for IRQ lock * @request_key: lockdep class for IRQ request * - * Context: potentially before irqs will work + * Context: potentially before IRQs will work * - * The gpio chip automatically be released when the device is unbound. + * The GPIO chip automatically be released when the device is unbound. * * Returns: * A negative errno if the chip can't be registered, such as because the diff --git a/drivers/gpio/gpiolib-legacy.c b/drivers/gpio/gpiolib-legacy.c index 5a9911ae9125..d27142418f9f 100644 --- a/drivers/gpio/gpiolib-legacy.c +++ b/drivers/gpio/gpiolib-legacy.c @@ -22,6 +22,9 @@ EXPORT_SYMBOL_GPL(gpio_free); * @label: a literal description string of this GPIO * * **DEPRECATED** This function is deprecated and must not be used in new code. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) { diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index cb0cefaec37e..7c0e2528d097 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -43,22 +43,25 @@ enum of_gpio_flags { /** * of_gpio_named_count() - Count GPIOs for a device * @np: device node to count GPIOs for - * @propname: property name containing gpio specifier(s) + * @propname: property name containing GPIO specifier(s) * * The function returns the count of GPIOs specified for a node. - * Note that the empty GPIO specifiers count too. Returns either - * Number of gpios defined in property, - * -EINVAL for an incorrectly formed gpios property, or - * -ENOENT for a missing gpios property + * NOTE: The empty GPIO specifiers count too. * - * Example: - * gpios = <0 - * &gpio1 1 2 - * 0 - * &gpio2 3 4>; + * Returns: + * Either number of GPIOs defined in the property, or + * * -EINVAL for an incorrectly formed "gpios" property, or + * * -ENOENT for a missing "gpios" property. + * + * Example:: + * + * gpios = <0 + * &gpio1 1 2 + * 0 + * &gpio2 3 4>; * * The above example defines four GPIOs, two of which are not specified. - * This function will return '4' + * This function will return '4'. */ static int of_gpio_named_count(const struct device_node *np, const char *propname) @@ -77,6 +80,11 @@ static int of_gpio_named_count(const struct device_node *np, * "gpios" for the chip select lines. If we detect this, we redirect * the counting of "cs-gpios" to count "gpios" transparent to the * driver. + * + * Returns: + * Either number of GPIOs defined in the property, or + * * -EINVAL for an incorrectly formed "gpios" property, or + * * -ENOENT for a missing "gpios" property. */ static int of_gpio_spi_cs_get_count(const struct device_node *np, const char *con_id) @@ -151,7 +159,7 @@ static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip, } /* - * Overrides stated polarity of a gpio line and warns when there is a + * Overrides stated polarity of a GPIO line and warns when there is a * discrepancy. */ static void of_gpio_quirk_polarity(const struct device_node *np, @@ -174,7 +182,7 @@ static void of_gpio_quirk_polarity(const struct device_node *np, /* * This quirk does static polarity overrides in cases where existing - * DTS specified incorrect polarity. + * device tree specified incorrect polarity. */ static void of_gpio_try_fixup_polarity(const struct device_node *np, const char *propname, @@ -275,7 +283,7 @@ static void of_gpio_set_polarity_by_property(const struct device_node *np, #if IS_ENABLED(CONFIG_MMC_ATMELMCI) /* * The Atmel HSMCI has compatible property in the parent node and - * gpio property in a child node + * GPIO property in a child node. */ if (of_device_is_compatible(np->parent, "atmel,hsmci")) { np_compat = np->parent; @@ -361,11 +369,12 @@ static void of_gpio_flags_quirks(const struct device_node *np, /** * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API * @np: device node to get GPIO from - * @propname: property name containing gpio specifier(s) + * @propname: property name containing GPIO specifier(s) * @index: index of the GPIO * @flags: a flags pointer to fill in * - * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno + * Returns: + * GPIO descriptor to use with Linux GPIO API, or one of the errno * value on the error condition. If @flags is not NULL the function also fills * in flags for the GPIO. */ @@ -412,12 +421,13 @@ static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np, /** * of_get_named_gpio() - Get a GPIO number to use with GPIO API * @np: device node to get GPIO from - * @propname: Name of property containing gpio specifier(s) + * @propname: Name of property containing GPIO specifier(s) * @index: index of the GPIO * * **DEPRECATED** This function is deprecated and must not be used in new code. * - * Returns GPIO number to use with Linux generic GPIO API, or one of the errno + * Returns: + * GPIO number to use with Linux generic GPIO API, or one of the errno * value on the error condition. */ int of_get_named_gpio(const struct device_node *np, const char *propname, @@ -475,7 +485,7 @@ static struct gpio_desc *of_find_gpio_rename(struct device_node *np, /* * Compatible string can be set to NULL in case where * matching to a particular compatible is not practical, - * but it should only be done for gpio names that have + * but it should only be done for GPIO names that have * vendor prefix to reduce risk of false positives. * Addition of such entries is strongly discouraged. */ @@ -587,7 +597,7 @@ static struct gpio_desc *of_find_gpio_rename(struct device_node *np, legacy_id = gpios[i].legacy_id ?: gpios[i].con_id; desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags); if (!gpiod_not_found(desc)) { - pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n", + pr_info("%s uses legacy GPIO name '%s' instead of '%s-gpios'\n", of_node_full_name(np), legacy_id, con_id); return desc; } @@ -622,7 +632,7 @@ static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np, desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags); if (!gpiod_not_found(desc)) - pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n", + pr_info("%s is using legacy GPIO name '%s' instead of '%s-gpios'\n", of_node_full_name(np), legacy_id, con_id); return desc; @@ -654,7 +664,6 @@ static struct gpio_desc *of_find_trigger_gpio(struct device_node *np, return desc; } - typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np, const char *con_id, unsigned int idx, @@ -708,11 +717,11 @@ struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id, * @chip: GPIO chip whose hog is parsed * @idx: Index of the GPIO to parse * @name: GPIO line name - * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from - * of_find_gpio() or of_parse_own_gpio() + * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from *_find_gpio() * @dflags: gpiod_flags - optional GPIO initialization flags * - * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno + * Returns: + * GPIO descriptor to use with Linux GPIO API, or one of the errno * value on the error condition. */ static struct gpio_desc *of_parse_own_gpio(struct device_node *np, @@ -777,10 +786,11 @@ static struct gpio_desc *of_parse_own_gpio(struct device_node *np, /** * of_gpiochip_add_hog - Add all hogs in a hog device node - * @chip: gpio chip to act on + * @chip: GPIO chip to act on * @hog: device node describing the hogs * - * Returns error if it fails otherwise 0 on success. + * Returns: + * 0 on success, or negative errno on failure. */ static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) { @@ -809,12 +819,14 @@ static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) } /** - * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions - * @chip: gpio chip to act on + * of_gpiochip_scan_gpios - Scan gpio-controller for GPIO definitions + * @chip: GPIO chip to act on * - * This is only used by of_gpiochip_add to request/set GPIO initial + * This is only used by of_gpiochip_add() to request/set GPIO initial * configuration. - * It returns error if it fails otherwise 0 on success. + * + * Returns: + * 0 on success, or negative errno on failure. */ static int of_gpiochip_scan_gpios(struct gpio_chip *chip) { @@ -840,7 +852,7 @@ static int of_gpiochip_scan_gpios(struct gpio_chip *chip) #ifdef CONFIG_OF_DYNAMIC /** * of_gpiochip_remove_hog - Remove all hogs in a hog device node - * @chip: gpio chip to act on + * @chip: GPIO chip to act on * @hog: device node describing the hogs */ static void of_gpiochip_remove_hog(struct gpio_chip *chip, @@ -920,13 +932,16 @@ struct notifier_block gpio_of_notifier = { /** * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags - * @gc: pointer to the gpio_chip structure + * @gc: pointer to the struct gpio_chip * @gpiospec: GPIO specifier as found in the device tree * @flags: a flags pointer to fill in * * This is simple translation function, suitable for the most 1:1 mapped * GPIO chips. This function performs only one sanity check: whether GPIO - * is less than ngpios (that is specified in the gpio_chip). + * is less than ngpios (that is specified in the @gc). + * + * Returns: + * GPIO number (>= 0) on success, negative errno on failure. */ static int of_gpio_simple_xlate(struct gpio_chip *gc, const struct of_phandle_args *gpiospec, @@ -934,7 +949,7 @@ static int of_gpio_simple_xlate(struct gpio_chip *gc, { /* * We're discouraging gpio_cells < 2, since that way you'll have to - * write your own xlate function (that will have to retrieve the GPIO + * write your own .xlate function (that will have to retrieve the GPIO * number and the flags from a single gpio cell -- this is possible, * but not recommended). */ @@ -960,22 +975,27 @@ static int of_gpio_simple_xlate(struct gpio_chip *gc, /** * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank) * @np: device node of the GPIO chip - * @mm_gc: pointer to the of_mm_gpio_chip allocated structure + * @mm_gc: pointer to the allocated struct of_mm_gpio_chip * @data: driver data to store in the struct gpio_chip * - * To use this function you should allocate and fill mm_gc with: + * **DEPRECATED** This function is deprecated and must not be used in new code. * - * 1) In the gpio_chip structure: + * To use this function you should allocate and fill @mm_gc with: + * + * 1) In the struct gpio_chip: * - all the callbacks * - of_gpio_n_cells * - of_xlate callback (optional) * - * 3) In the of_mm_gpio_chip structure: + * 3) In the struct of_mm_gpio_chip: * - save_regs callback (optional) * * If succeeded, this function will map bank's memory and will * do all necessary work for you. Then you'll able to use .regs * to manage GPIOs from the callbacks. + * + * Returns: + * 0 on success, or negative errno on failure. */ int of_mm_gpiochip_add_data(struct device_node *np, struct of_mm_gpio_chip *mm_gc, @@ -1018,7 +1038,9 @@ EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data); /** * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank) - * @mm_gc: pointer to the of_mm_gpio_chip allocated structure + * @mm_gc: pointer to the allocated struct of_mm_gpio_chip + * + * **DEPRECATED** This function is deprecated and must not be used in new code. */ void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc) { diff --git a/drivers/gpio/gpiolib-swnode.c b/drivers/gpio/gpiolib-swnode.c index fa52bdb1a29a..100fc18a468c 100644 --- a/drivers/gpio/gpiolib-swnode.c +++ b/drivers/gpio/gpiolib-swnode.c @@ -21,7 +21,7 @@ static void swnode_format_propname(const char *con_id, char *propname, size_t max_size) { /* - * Note we do not need to try both -gpios and -gpio suffixes, + * NOTE: We do not need to try both -gpios and -gpio suffixes, * as, unlike OF and ACPI, we can fix software nodes to conform * to the proper binding. */ @@ -92,12 +92,12 @@ struct gpio_desc *swnode_find_gpio(struct fwnode_handle *fwnode, /** * swnode_gpio_count - count the GPIOs associated with a device / function - * @fwnode: firmware node of the GPIO consumer, can be %NULL for + * @fwnode: firmware node of the GPIO consumer, can be NULL for * system-global GPIOs * @con_id: function within the GPIO consumer * - * Return: - * The number of GPIOs associated with a device / function or %-ENOENT, + * Returns: + * The number of GPIOs associated with a device / function or -ENOENT, * if no GPIO has been assigned to the requested function. */ int swnode_gpio_count(const struct fwnode_handle *fwnode, const char *con_id) diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index 26202586fd39..94f75ebca32f 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -44,8 +44,8 @@ struct gpiod_data { }; /* - * Lock to serialise gpiod export and unexport, and prevent re-export of - * gpiod whose chip is being unregistered. + * Lock to serialise GPIO export and unexport, and prevent re-export of + * GPIO whose chip is being unregistered. */ static DEFINE_MUTEX(sysfs_lock); @@ -193,12 +193,12 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags) IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; /* - * FIXME: This should be done in the irq_request_resources callback - * when the irq is requested, but a few drivers currently fail - * to do so. + * FIXME: This should be done in the .irq_request_resources callback + * when the IRQ is requested, but a few drivers currently fail + * to do so. * - * Remove this redundant call (along with the corresponding - * unlock) when those drivers have been fixed. + * Remove this redundant call (along with the corresponding + * unlock) when those drivers have been fixed. */ ret = gpiochip_lock_as_irq(guard.gc, gpio_chip_hwgpio(desc)); if (ret < 0) @@ -222,7 +222,7 @@ static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags) } /* - * Caller holds gpiod-data mutex (unless called after class-device + * Caller holds gpiod_data mutex (unless called after class-device * deregistration). */ static void gpio_sysfs_free_irq(struct device *dev) @@ -299,7 +299,7 @@ static ssize_t edge_store(struct device *dev, } static DEVICE_ATTR_RW(edge); -/* Caller holds gpiod-data mutex. */ +/* Caller holds gpiod_data mutex. */ static int gpio_sysfs_set_active_low(struct device *dev, int value) { struct gpiod_data *data = dev_get_drvdata(dev); @@ -477,7 +477,8 @@ static ssize_t export_store(const struct class *class, return -EINVAL; } - /* No extra locking here; FLAG_SYSFS just signifies that the + /* + * No extra locking here; FLAG_SYSFS just signifies that the * request and export were done by on behalf of userspace, so * they may be undone on its behalf too. */ @@ -526,7 +527,8 @@ static ssize_t unexport_store(const struct class *class, status = -EINVAL; - /* No extra locking here; FLAG_SYSFS just signifies that the + /* + * No extra locking here; FLAG_SYSFS just signifies that the * request and export were done by on behalf of userspace, so * they may be undone on its behalf too. */ @@ -568,7 +570,8 @@ static struct class gpio_class = { * will see "direction" sysfs attribute which may be used to change * the gpio's direction. A "value" attribute will always be provided. * - * Returns zero on success, else an error. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_export(struct gpio_desc *desc, bool direction_may_change) { @@ -667,7 +670,8 @@ static int match_export(struct device *dev, const void *desc) * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN * node. Caller is responsible for unlinking. * - * Returns zero on success, else an error. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_export_link(struct device *dev, const char *name, struct gpio_desc *desc) @@ -723,7 +727,7 @@ void gpiod_unexport(struct gpio_desc *desc) device_unregister(dev); /* - * Release irq after deregistration to prevent race with edge_store. + * Release IRQ after deregistration to prevent race with edge_store. */ if (data->irq_flags) gpio_sysfs_free_irq(dev); @@ -747,7 +751,7 @@ int gpiochip_sysfs_register(struct gpio_device *gdev) struct device *dev; /* - * Many systems add gpio chips for SOC support very early, + * Many systems add GPIO chips for SoC support very early, * before driver model support is available. In those cases we * register later, in gpiolib_sysfs_init() ... here we just * verify that _some_ field of gpio_class got initialized. @@ -795,7 +799,7 @@ void gpiochip_sysfs_unregister(struct gpio_device *gdev) device_unregister(gdev->mockdev); - /* prevent further gpiod exports */ + /* prevent further GPIO exports */ gdev->mockdev = NULL; } @@ -805,7 +809,7 @@ void gpiochip_sysfs_unregister(struct gpio_device *gdev) if (!chip) return; - /* unregister gpiod class devices owned by sysfs */ + /* unregister GPIO class devices owned by sysfs */ for_each_gpio_desc_with_flag(chip, desc, FLAG_SYSFS) { gpiod_unexport(desc); gpiod_free(desc); @@ -840,7 +844,8 @@ static int __init gpiolib_sysfs_init(void) if (status < 0) return status; - /* Scan and register the gpio_chips which registered very + /* + * Scan and register the gpio_chips which registered very * early (e.g. before the class_register above was called). * * We run before arch_initcall() so chip->dev nodes can have diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index f749ece2d3cd..29c9374f8843 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -41,10 +41,11 @@ #define CREATE_TRACE_POINTS #include <trace/events/gpio.h> -/* Implementation infrastructure for GPIO interfaces. +/* + * Implementation infrastructure for GPIO interfaces. * * The GPIO programming interface allows for inlining speed-critical - * get/set operations for common cases, so that access to SOC-integrated + * get/set operations for common cases, so that access to SoC-integrated * GPIOs can sometimes cost only an instruction or two per bit. */ @@ -72,7 +73,7 @@ static const struct bus_type gpio_bus_type = { }; /* - * Number of GPIOs to use for the fast path in set array + * Number of GPIOs to use for the fast path in set array. */ #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT @@ -134,7 +135,7 @@ static int desc_set_label(struct gpio_desc *desc, const char *label) * @gpio: global GPIO number * * Returns: - * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO + * The GPIO descriptor associated with the given GPIO, or NULL if no GPIO * with the given number exists in the system. */ struct gpio_desc *gpio_to_desc(unsigned gpio) @@ -169,8 +170,8 @@ EXPORT_SYMBOL_GPL(gpiochip_get_desc); * @hwnum: hardware number of the GPIO for this chip * * Returns: - * A pointer to the GPIO descriptor or %EINVAL if no GPIO exists in the given - * chip for the specified hardware number or %ENODEV if the underlying chip + * A pointer to the GPIO descriptor or -EINVAL if no GPIO exists in the given + * chip for the specified hardware number or -ENODEV if the underlying chip * already vanished. * * The reference count of struct gpio_device is *NOT* increased like when the @@ -204,7 +205,6 @@ int desc_to_gpio(const struct gpio_desc *desc) } EXPORT_SYMBOL_GPL(desc_to_gpio); - /** * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs * @desc: descriptor to return the chip of @@ -213,6 +213,9 @@ EXPORT_SYMBOL_GPL(desc_to_gpio); * This function is unsafe and should not be used. Using the chip address * without taking the SRCU read lock may result in dereferencing a dangling * pointer. + * + * Returns: + * Address of the GPIO chip backing this device. */ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) { @@ -272,7 +275,7 @@ const char *gpio_device_get_label(struct gpio_device *gdev) EXPORT_SYMBOL(gpio_device_get_label); /** - * gpio_device_get_chip() - Get the gpio_chip implementation of this GPIO device + * gpio_device_get_chip() - Get the GPIO chip implementation of this GPIO device * @gdev: GPIO device * * Returns: @@ -325,7 +328,8 @@ static int gpiochip_find_base_unlocked(u16 ngpio) * gpiod_get_direction - return the current direction of a GPIO * @desc: GPIO to get the direction of * - * Returns 0 for output, 1 for input, or an error code in case of error. + * Returns: + * 0 for output, 1 for input, or an error code in case of error. * * This function may sleep if gpiod_cansleep() is true. */ @@ -380,10 +384,10 @@ EXPORT_SYMBOL_GPL(gpiod_get_direction); /* * Add a new chip to the global chips list, keeping the list of chips sorted - * by range(means [base, base + ngpio - 1]) order. + * by range (means [base, base + ngpio - 1]) order. * - * Return -EBUSY if the new chip overlaps with some other chip's integer - * space. + * Returns: + * -EBUSY if the new chip overlaps with some other chip's integer space. */ static int gpiodev_add_to_list_unlocked(struct gpio_device *gdev) { @@ -430,8 +434,8 @@ static int gpiodev_add_to_list_unlocked(struct gpio_device *gdev) } /* - * Convert a GPIO name to its descriptor - * Note that there is no guarantee that GPIO names are globally unique! + * Convert a GPIO name to its descriptor. + * NOTE: There is no guarantee that GPIO names are globally unique! * Hence this function will return, if it exists, a reference to the first GPIO * line found that matches the given name. */ @@ -467,7 +471,7 @@ static struct gpio_desc *gpio_name_to_desc(const char * const name) * Take the names from gc->names and assign them to their GPIO descriptors. * Warn if a name is already used for a GPIO line on a different GPIO chip. * - * Note that: + * NOTE: * 1. Non-unique names are still accepted, * 2. Name collisions within the same GPIO chip are not reported. */ @@ -517,11 +521,11 @@ static int gpiochip_set_names(struct gpio_chip *chip) /* * When offset is set in the driver side we assume the driver internally - * is using more than one gpiochip per the same device. We have to stop + * is using more than one GPIO chip per the same device. We have to stop * setting friendly names if the specified ones with 'gpio-line-names' * are less than the offset in the device itself. This means all the * lines are not present for every single pin within all the internal - * gpiochips. + * GPIO chips. */ if (count <= chip->offset) { dev_warn(dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n", @@ -542,8 +546,8 @@ static int gpiochip_set_names(struct gpio_chip *chip) } /* - * When more that one gpiochip per device is used, 'count' can - * contain at most number gpiochips x chip->ngpio. We have to + * When more that one GPIO chip per device is used, 'count' can + * contain at most number GPIO chips x chip->ngpio. We have to * correctly distribute all defined lines taking into account * chip->offset as starting point from where we will assign * the names to pins from the 'names' array. Since property @@ -1096,10 +1100,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key); /** - * gpiochip_remove() - unregister a gpio_chip + * gpiochip_remove() - unregister a GPIO chip * @gc: the chip to unregister * - * A gpio_chip with any GPIOs still requested may not be removed. + * A GPIO chip with any GPIOs still requested may not be removed. */ void gpiochip_remove(struct gpio_chip *gc) { @@ -1128,7 +1132,7 @@ void gpiochip_remove(struct gpio_chip *gc) gpiochip_set_data(gc, NULL); /* - * The gpiochip side puts its use of the device to rest here: + * The GPIO chip side puts its use of the device to rest here: * if there are no userspace clients, the chardev and device will * be removed, else it will be dangling until the last user is * gone. @@ -1141,7 +1145,7 @@ EXPORT_SYMBOL_GPL(gpiochip_remove); /** * gpio_device_find() - find a specific GPIO device * @data: data to pass to match function - * @match: Callback function to check gpio_chip + * @match: Callback function to check struct gpio_chip * * Returns: * New reference to struct gpio_device. @@ -1152,9 +1156,9 @@ EXPORT_SYMBOL_GPL(gpiochip_remove); * returns non-zero, this function will return to the caller and not iterate * over any more gpio_devices. * - * The callback takes the GPIO chip structure as argument. During the execution - * of the callback function the chip is protected from being freed. TODO: This - * actually has yet to be implemented. + * The callback takes the struct gpio_chip as argument. During the execution + * of the callback function the chip is protected from being freed. + * TODO: this actually has yet to be implemented. * * If the function returns non-NULL, the returned reference must be freed by * the caller using gpio_device_put(). @@ -1273,7 +1277,7 @@ EXPORT_SYMBOL_GPL(gpio_device_to_device); #ifdef CONFIG_GPIOLIB_IRQCHIP /* - * The following is irqchip helper code for gpiochips. + * The following is irqchip helper code for GPIO chips. */ static int gpiochip_irqchip_init_hw(struct gpio_chip *gc) @@ -1321,9 +1325,8 @@ static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc, #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY /** - * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip - * to a gpiochip - * @gc: the gpiochip to set the irqchip hierarchical handler to + * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip to a GPIO chip + * @gc: the GPIO chip to set the irqchip hierarchical handler to * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt * will then percolate up to the parent */ @@ -1336,7 +1339,7 @@ static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc, /* * This is for legacy and boardfile "irqchip" fwnodes: allocate - * irqs upfront instead of dynamically since we don't have the + * IRQs upfront instead of dynamically since we don't have the * dynamic type of allocation that hardware description languages * provide. Once all GPIO drivers using board files are gone from * the kernel we can delete this code, but for a transitional period @@ -1396,9 +1399,8 @@ static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d, unsigned int *type) { /* We support standard DT translation */ - if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) { + if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) return irq_domain_translate_twocell(d, fwspec, hwirq, type); - } /* This is for board files and others not using DT */ if (is_fwnode_irqchip(fwspec->fwnode)) { @@ -1449,7 +1451,7 @@ static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d, chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq); /* - * We set handle_bad_irq because the .set_type() should + * Driver has to set handle_bad_irq() because the .set_type() should * always be invoked and set the right type of handler. */ irq_domain_set_info(d, @@ -1473,7 +1475,7 @@ static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d, ret = irq_domain_alloc_irqs_parent(d, irq, 1, &gpio_parent_fwspec); /* * If the parent irqdomain is msi, the interrupts have already - * been allocated, so the EEXIST is good. + * been allocated, so the -EEXIST is good. */ if (irq_domain_is_msi(d->parent) && (ret == -EEXIST)) ret = 0; @@ -1493,13 +1495,16 @@ static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc, /** * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ - * @domain: The IRQ domain used by this IRQ chip + * @domain: The IRQ domain used by this irqchip * @data: Outermost irq_data associated with the IRQ * @reserve: If set, only reserve an interrupt vector instead of assigning one * * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be * used as the activate function for the &struct irq_domain_ops. The host_data * for the IRQ domain must be the &struct gpio_chip. + * + * Returns: + * 0 on success, or negative errno on failure. */ static int gpiochip_irq_domain_activate(struct irq_domain *domain, struct irq_data *data, bool reserve) @@ -1512,7 +1517,7 @@ static int gpiochip_irq_domain_activate(struct irq_domain *domain, /** * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ - * @domain: The IRQ domain used by this IRQ chip + * @domain: The IRQ domain used by this irqchip * @data: Outermost irq_data associated with the IRQ * * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to @@ -1638,12 +1643,15 @@ static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) /** * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip * @d: the irqdomain used by this irqchip - * @irq: the global irq number used by this GPIO irqchip irq - * @hwirq: the local IRQ/GPIO line offset on this gpiochip + * @irq: the global IRQ number used by this GPIO irqchip IRQ + * @hwirq: the local IRQ/GPIO line offset on this GPIO chip * * This function will set up the mapping for a certain IRQ line on a - * gpiochip by assigning the gpiochip as chip data, and using the irqchip - * stored inside the gpiochip. + * GPIO chip by assigning the struct gpio_chip as chip data, and using the irqchip + * stored inside the struct gpio_chip. + * + * Returns: + * 0 on success, or negative errno on failure. */ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hwirq) @@ -1656,7 +1664,7 @@ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, irq_set_chip_data(irq, gc); /* - * This lock class tells lockdep that GPIO irqs are in a different + * This lock class tells lockdep that GPIO IRQs are in a different * category than their parents, so it won't report false recursion. */ irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key); @@ -1722,7 +1730,7 @@ static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset) /* * Avoid race condition with other code, which tries to lookup * an IRQ before the irqchip has been properly registered, - * i.e. while gpiochip is still being brought up. + * i.e. while GPIO chip is still being brought up. */ if (!gc->irq.initialized) return -EPROBE_DEFER; @@ -1874,10 +1882,13 @@ static int gpiochip_irqchip_add_allocated_domain(struct gpio_chip *gc, } /** - * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip - * @gc: the GPIO chip to add the IRQ chip to + * gpiochip_add_irqchip() - adds an irqchip to a GPIO chip + * @gc: the GPIO chip to add the irqchip to * @lock_key: lockdep class for IRQ lock * @request_key: lockdep class for IRQ request + * + * Returns: + * 0 on success, or a negative error-code on failure. */ static int gpiochip_add_irqchip(struct gpio_chip *gc, struct lock_class_key *lock_key, @@ -1914,11 +1925,10 @@ static int gpiochip_add_irqchip(struct gpio_chip *gc, gc->irq.request_key = request_key; /* If a parent irqdomain is provided, let's build a hierarchy */ - if (gpiochip_hierarchy_is_hierarchical(gc)) { + if (gpiochip_hierarchy_is_hierarchical(gc)) domain = gpiochip_hierarchy_create_domain(gc); - } else { + else domain = gpiochip_simple_create_domain(gc); - } if (IS_ERR(domain)) return PTR_ERR(domain); @@ -1932,8 +1942,8 @@ static int gpiochip_add_irqchip(struct gpio_chip *gc, data = gc->irq.parent_handler_data ?: gc; /* - * The parent IRQ chip is already using the chip_data - * for this IRQ chip, so our callbacks simply use the + * The parent irqchip is already using the chip_data + * for this irqchip, so our callbacks simply use the * handler_data. */ irq_set_chained_handler_and_data(gc->irq.parents[i], @@ -1954,10 +1964,10 @@ static int gpiochip_add_irqchip(struct gpio_chip *gc, } /** - * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip - * @gc: the gpiochip to remove the irqchip from + * gpiochip_irqchip_remove() - removes an irqchip added to a struct gpio_chip + * @gc: the struct gpio_chip to remove the irqchip from * - * This is called only from gpiochip_remove() + * This is called only from gpiochip_remove(). */ static void gpiochip_irqchip_remove(struct gpio_chip *gc) { @@ -2008,11 +2018,14 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gc) } /** - * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip - * @gc: the gpiochip to add the irqchip to - * @domain: the irqdomain to add to the gpiochip + * gpiochip_irqchip_add_domain() - adds an irqdomain to a struct gpio_chip + * @gc: the struct gpio_chip to add the irqchip to + * @domain: the irqdomain to add to the struct gpio_chip * - * This function adds an IRQ domain to the gpiochip. + * This function adds an IRQ domain to the struct gpio_chip. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiochip_irqchip_add_domain(struct gpio_chip *gc, struct irq_domain *domain) @@ -2046,9 +2059,12 @@ static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc) #endif /* CONFIG_GPIOLIB_IRQCHIP */ /** - * gpiochip_generic_request() - request the gpio function for a pin - * @gc: the gpiochip owning the GPIO + * gpiochip_generic_request() - request the GPIO function for a pin + * @gc: the GPIO chip owning the GPIO * @offset: the offset of the GPIO to request for GPIO function + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset) { @@ -2062,8 +2078,8 @@ int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset) EXPORT_SYMBOL_GPL(gpiochip_generic_request); /** - * gpiochip_generic_free() - free the gpio function from a pin - * @gc: the gpiochip to request the gpio function for + * gpiochip_generic_free() - free the GPIO function from a pin + * @gc: the GPIO chip to request the GPIO function for * @offset: the offset of the GPIO to free from GPIO function */ void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset) @@ -2079,9 +2095,12 @@ EXPORT_SYMBOL_GPL(gpiochip_generic_free); /** * gpiochip_generic_config() - apply configuration for a pin - * @gc: the gpiochip owning the GPIO + * @gc: the GPIO chip owning the GPIO * @offset: the offset of the GPIO to apply the configuration * @config: the configuration to be applied + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset, unsigned long config) @@ -2099,15 +2118,18 @@ EXPORT_SYMBOL_GPL(gpiochip_generic_config); /** * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping - * @gc: the gpiochip to add the range for + * @gc: the GPIO chip to add the range for * @pctldev: the pin controller to map to - * @gpio_offset: the start offset in the current gpio_chip number space + * @gpio_offset: the start offset in the current @gc number space * @pin_group: name of the pin group inside the pin controller * * Calling this function directly from a DeviceTree-supported * pinctrl driver is DEPRECATED. Please see Section 2.1 of * Documentation/devicetree/bindings/gpio/gpio.txt on how to - * bind pinctrl and gpio drivers via the "gpio-ranges" property. + * bind pinctrl and GPIO drivers via the "gpio-ranges" property. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiochip_add_pingroup_range(struct gpio_chip *gc, struct pinctrl_dev *pctldev, @@ -2152,20 +2174,20 @@ EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); /** * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping - * @gc: the gpiochip to add the range for + * @gc: the GPIO chip to add the range for * @pinctl_name: the dev_name() of the pin controller to map to - * @gpio_offset: the start offset in the current gpio_chip number space + * @gpio_offset: the start offset in the current @gc number space * @pin_offset: the start offset in the pin controller number space * @npins: the number of pins from the offset of each pin space (GPIO and * pin controller) to accumulate in this range * - * Returns: - * 0 on success, or a negative error-code on failure. - * * Calling this function directly from a DeviceTree-supported * pinctrl driver is DEPRECATED. Please see Section 2.1 of * Documentation/devicetree/bindings/gpio/gpio.txt on how to - * bind pinctrl and gpio drivers via the "gpio-ranges" property. + * bind pinctrl and GPIO drivers via the "gpio-ranges" property. + * + * Returns: + * 0 on success, or a negative error-code on failure. */ int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name, unsigned int gpio_offset, unsigned int pin_offset, @@ -2227,7 +2249,8 @@ EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); #endif /* CONFIG_PINCTRL */ -/* These "optional" allocation calls help prevent drivers from stomping +/* + * These "optional" allocation calls help prevent drivers from stomping * on each other, and help provide better diagnostics in debugfs. * They're called even less than the "set direction" calls. */ @@ -2243,10 +2266,11 @@ static int gpiod_request_commit(struct gpio_desc *desc, const char *label) if (test_and_set_bit(FLAG_REQUESTED, &desc->flags)) return -EBUSY; - /* NOTE: gpio_request() can be called in early boot, - * before IRQs are enabled, for non-sleeping (SOC) GPIOs. + /* + * NOTE: + * gpio_request() can be called in early boot, before IRQs are enabled, + * for non-sleeping (SoC) GPIOs. */ - if (guard.gc->request) { offset = gpio_chip_hwgpio(desc); if (gpiochip_line_is_valid(guard.gc, offset)) @@ -2373,7 +2397,7 @@ void gpiod_free(struct gpio_desc *desc) * Returns: * Pointer to a copy of the consumer label if the line is requested or NULL * if it's not. If a valid pointer was returned, it must be freed using - * kfree(). In case of a memory allocation error, the function returns %ENOMEM. + * kfree(). In case of a memory allocation error, the function returns -ENOMEM. * * Must not be called from atomic context. */ @@ -2475,10 +2499,9 @@ EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); * * As a rule these aren't called more than once (except for drivers * using the open-drain emulation idiom) so these are natural places - * to accumulate extra debugging checks. Note that we can't (yet) + * to accumulate extra debugging checks. NOTE: We can't (yet) * rely on gpio_request() having been called beforehand. */ - static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset, unsigned long config) { @@ -2569,7 +2592,8 @@ static int gpio_set_bias(struct gpio_desc *desc) * The function calls the certain GPIO driver to set debounce timeout * in the hardware. * - * Returns 0 on success, or negative error code otherwise. + * Returns: + * 0 on success, or negative errno on failure. */ int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce) { @@ -2585,7 +2609,8 @@ int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce) * Set the direction of the passed GPIO to input, such as gpiod_get_value() can * be called safely on it. * - * Return 0 in case of success, else an error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_direction_input(struct gpio_desc *desc) { @@ -2646,7 +2671,7 @@ static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) return -ENODEV; /* - * It's OK not to specify .direction_output() if the gpiochip is + * It's OK not to specify .direction_output() if the GPIO chip is * output-only, but if there is then not even a .set() operation it * is pretty tricky to drive the output line. */ @@ -2692,7 +2717,8 @@ static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) * be called safely on it. The initial value of the output must be specified * as raw value on the physical line without regard for the ACTIVE_LOW status. * - * Return 0 in case of success, else an error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_direction_output_raw(struct gpio_desc *desc, int value) { @@ -2711,7 +2737,8 @@ EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into * account. * - * Return 0 in case of success, else an error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_direction_output(struct gpio_desc *desc, int value) { @@ -2784,7 +2811,8 @@ EXPORT_SYMBOL_GPL(gpiod_direction_output); * @desc: GPIO to enable. * @flags: Flags related to GPIO edge. * - * Return 0 in case of success, else negative error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags) { @@ -2816,7 +2844,8 @@ EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns); * @desc: GPIO to disable. * @flags: Flags related to GPIO edge, same value as used during enable call. * - * Return 0 in case of success, else negative error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags) { @@ -2848,7 +2877,7 @@ EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns); * @config: Same packed config format as generic pinconf * * Returns: - * 0 on success, %-ENOTSUPP if the controller doesn't support setting the + * 0 on success, -ENOTSUPP if the controller doesn't support setting the * configuration. */ int gpiod_set_config(struct gpio_desc *desc, unsigned long config) @@ -2869,7 +2898,7 @@ EXPORT_SYMBOL_GPL(gpiod_set_config); * @debounce: debounce time in microseconds * * Returns: - * 0 on success, %-ENOTSUPP if the controller doesn't support setting the + * 0 on success, -ENOTSUPP if the controller doesn't support setting the * debounce time. */ int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce) @@ -2906,9 +2935,10 @@ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) /** * gpiod_is_active_low - test whether a GPIO is active-low or not - * @desc: the gpio descriptor to test + * @desc: the GPIO descriptor to test * - * Returns 1 if the GPIO is active-low, 0 otherwise. + * Returns: + * 1 if the GPIO is active-low, 0 otherwise. */ int gpiod_is_active_low(const struct gpio_desc *desc) { @@ -2919,7 +2949,7 @@ EXPORT_SYMBOL_GPL(gpiod_is_active_low); /** * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not - * @desc: the gpio descriptor to change + * @desc: the GPIO descriptor to change */ void gpiod_toggle_active_low(struct gpio_desc *desc) { @@ -2933,7 +2963,8 @@ static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *des return gc->get ? gc->get(gc, gpio_chip_hwgpio(desc)) : -EIO; } -/* I/O calls are only valid after configuration completed; the relevant +/* + * I/O calls are only valid after configuration completed; the relevant * "is this a valid GPIO" error checks should already have been done. * * "Get" operations are often inlinable as reading a pin value register, @@ -2947,7 +2978,7 @@ static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *des * * IMPORTANT!!! The hot paths -- get/set value -- assume that callers * have requested the GPIO. That can include implicit requesting by - * a direction setting call. Marking a gpio as requested locks its chip + * a direction setting call. Marking a GPIO as requested locks its chip * in memory, guaranteeing that these table lookups need no more locking * and that gpiochip_remove() will fail. * @@ -2961,7 +2992,7 @@ static int gpiod_get_raw_value_commit(const struct gpio_desc *desc) struct gpio_chip *gc; int value; - /* FIXME Unable to use gpio_chip_guard due to const desc. */ + /* FIXME: Unable to use gpio_chip_guard() due to const desc. */ gdev = desc->gdev; guard(srcu)(&gdev->srcu); @@ -3120,10 +3151,11 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep, } /** - * gpiod_get_raw_value() - return a gpio's raw value - * @desc: gpio whose value will be returned + * gpiod_get_raw_value() - return a GPIO's raw value + * @desc: GPIO whose value will be returned * - * Return the GPIO's raw value, i.e. the value of the physical line disregarding + * Returns: + * The GPIO's raw value, i.e. the value of the physical line disregarding * its ACTIVE_LOW status, or negative errno on failure. * * This function can be called from contexts where we cannot sleep, and will @@ -3139,10 +3171,11 @@ int gpiod_get_raw_value(const struct gpio_desc *desc) EXPORT_SYMBOL_GPL(gpiod_get_raw_value); /** - * gpiod_get_value() - return a gpio's value - * @desc: gpio whose value will be returned + * gpiod_get_value() - return a GPIO's value + * @desc: GPIO whose value will be returned * - * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into + * Returns: + * The GPIO's logical value, i.e. taking the ACTIVE_LOW status into * account, or negative errno on failure. * * This function can be called from contexts where we cannot sleep, and will @@ -3175,11 +3208,13 @@ EXPORT_SYMBOL_GPL(gpiod_get_value); * @value_bitmap: bitmap to store the read values * * Read the raw values of the GPIOs, i.e. the values of the physical lines - * without regard for their ACTIVE_LOW status. Return 0 in case of success, - * else an error code. + * without regard for their ACTIVE_LOW status. * * This function can be called from contexts where we cannot sleep, * and it will complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_raw_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3202,10 +3237,13 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value); * @value_bitmap: bitmap to store the read values * * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status - * into account. Return 0 in case of success, else an error code. + * into account. * * This function can be called from contexts where we cannot sleep, * and it will complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3221,8 +3259,8 @@ int gpiod_get_array_value(unsigned int array_size, EXPORT_SYMBOL_GPL(gpiod_get_array_value); /* - * gpio_set_open_drain_value_commit() - Set the open drain gpio's value. - * @desc: gpio descriptor whose state need to be set. + * gpio_set_open_drain_value_commit() - Set the open drain GPIO's value. + * @desc: GPIO descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherwise it will set to LOW. */ static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) @@ -3248,8 +3286,8 @@ static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) } /* - * _gpio_set_open_source_value() - Set the open source gpio's value. - * @desc: gpio descriptor whose state need to be set. + * _gpio_set_open_source_value() - Set the open source GPIO's value. + * @desc: GPIO descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherwise it will set to LOW. */ static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value) @@ -3421,8 +3459,8 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep, } /** - * gpiod_set_raw_value() - assign a gpio's raw value - * @desc: gpio whose value will be assigned + * gpiod_set_raw_value() - assign a GPIO's raw value + * @desc: GPIO whose value will be assigned * @value: value to assign * * Set the raw value of the GPIO, i.e. the value of its physical line without @@ -3462,8 +3500,8 @@ static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value) } /** - * gpiod_set_value() - assign a gpio's value - * @desc: gpio whose value will be assigned + * gpiod_set_value() - assign a GPIO's value + * @desc: GPIO whose value will be assigned * @value: value to assign * * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW, @@ -3493,6 +3531,9 @@ EXPORT_SYMBOL_GPL(gpiod_set_value); * * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_raw_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3518,6 +3559,9 @@ EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); * * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3533,9 +3577,11 @@ int gpiod_set_array_value(unsigned int array_size, EXPORT_SYMBOL_GPL(gpiod_set_array_value); /** - * gpiod_cansleep() - report whether gpio value access may sleep - * @desc: gpio to check + * gpiod_cansleep() - report whether GPIO value access may sleep + * @desc: GPIO to check * + * Returns: + * 0 for non-sleepable, 1 for sleepable, or an error code in case of error. */ int gpiod_cansleep(const struct gpio_desc *desc) { @@ -3546,8 +3592,11 @@ EXPORT_SYMBOL_GPL(gpiod_cansleep); /** * gpiod_set_consumer_name() - set the consumer name for the descriptor - * @desc: gpio to set the consumer name on + * @desc: GPIO to set the consumer name on * @name: the new consumer name + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name) { @@ -3559,10 +3608,10 @@ EXPORT_SYMBOL_GPL(gpiod_set_consumer_name); /** * gpiod_to_irq() - return the IRQ corresponding to a GPIO - * @desc: gpio whose IRQ will be returned (already requested) + * @desc: GPIO whose IRQ will be returned (already requested) * - * Return the IRQ corresponding to the passed GPIO, or an error code in case of - * error. + * Returns: + * The IRQ corresponding to the passed GPIO, or an error code in case of error. */ int gpiod_to_irq(const struct gpio_desc *desc) { @@ -3579,7 +3628,7 @@ int gpiod_to_irq(const struct gpio_desc *desc) return -EINVAL; gdev = desc->gdev; - /* FIXME Cannot use gpio_chip_guard due to const desc. */ + /* FIXME: Cannot use gpio_chip_guard() due to const desc. */ guard(srcu)(&gdev->srcu); gc = srcu_dereference(gdev->chip, &gdev->srcu); if (!gc) @@ -3600,7 +3649,7 @@ int gpiod_to_irq(const struct gpio_desc *desc) /* * Avoid race condition with other code, which tries to lookup * an IRQ before the irqchip has been properly registered, - * i.e. while gpiochip is still being brought up. + * i.e. while GPIO chip is still being brought up. */ return -EPROBE_DEFER; } @@ -3616,6 +3665,9 @@ EXPORT_SYMBOL_GPL(gpiod_to_irq); * * This is used directly by GPIO drivers that want to lock down * a certain GPIO line to be used for IRQs. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset) { @@ -3764,10 +3816,11 @@ bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset) 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 + * gpiod_get_raw_value_cansleep() - return a GPIO's raw value + * @desc: GPIO whose value will be returned * - * Return the GPIO's raw value, i.e. the value of the physical line disregarding + * Returns: + * The GPIO's raw value, i.e. the value of the physical line disregarding * its ACTIVE_LOW status, or negative errno on failure. * * This function is to be called from contexts that can sleep. @@ -3781,10 +3834,11 @@ int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); /** - * gpiod_get_value_cansleep() - return a gpio's value - * @desc: gpio whose value will be returned + * gpiod_get_value_cansleep() - return a GPIO's value + * @desc: GPIO whose value will be returned * - * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into + * Returns: + * The GPIO's logical value, i.e. taking the ACTIVE_LOW status into * account, or negative errno on failure. * * This function is to be called from contexts that can sleep. @@ -3814,10 +3868,12 @@ EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); * @value_bitmap: bitmap to store the read values * * Read the raw values of the GPIOs, i.e. the values of the physical lines - * without regard for their ACTIVE_LOW status. Return 0 in case of success, - * else an error code. + * without regard for their ACTIVE_LOW status. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_raw_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, @@ -3841,9 +3897,12 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep); * @value_bitmap: bitmap to store the read values * * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status - * into account. Return 0 in case of success, else an error code. + * into account. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, @@ -3860,8 +3919,8 @@ int gpiod_get_array_value_cansleep(unsigned int array_size, EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep); /** - * gpiod_set_raw_value_cansleep() - assign a gpio's raw value - * @desc: gpio whose value will be assigned + * gpiod_set_raw_value_cansleep() - assign a GPIO's raw value + * @desc: GPIO whose value will be assigned * @value: value to assign * * Set the raw value of the GPIO, i.e. the value of its physical line without @@ -3878,8 +3937,8 @@ void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); /** - * gpiod_set_value_cansleep() - assign a gpio's value - * @desc: gpio whose value will be assigned + * gpiod_set_value_cansleep() - assign a GPIO's value + * @desc: GPIO whose value will be assigned * @value: value to assign * * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into @@ -3906,6 +3965,9 @@ EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); * without regard for their ACTIVE_LOW status. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_raw_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, @@ -3948,6 +4010,9 @@ void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) * into account. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, @@ -3999,7 +4064,7 @@ EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table); /** * gpiod_add_hogs() - register a set of GPIO hogs from machine code - * @hogs: table of gpio hog entries with a zeroed sentinel at the end + * @hogs: table of GPIO hog entries with a zeroed sentinel at the end */ void gpiod_add_hogs(struct gpiod_hog *hogs) { @@ -4281,9 +4346,12 @@ EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index); /** * gpiod_count - return the number of GPIOs associated with a device / function - * or -ENOENT if no GPIO has been assigned to the requested function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer + * + * Returns: + * The number of GPIOs associated with a device / function or -ENOENT if no + * GPIO has been assigned to the requested function. */ int gpiod_count(struct device *dev, const char *con_id) { @@ -4310,7 +4378,8 @@ EXPORT_SYMBOL_GPL(gpiod_count); * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * - * Return the GPIO descriptor corresponding to the function con_id of device + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device * dev, -ENOENT if no GPIO has been assigned to the requested function, or * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ @@ -4330,6 +4399,11 @@ EXPORT_SYMBOL_GPL(gpiod_get); * This is equivalent to gpiod_get(), except that when no GPIO was assigned to * the requested function it will return NULL. This is convenient for drivers * that need to handle optional GPIOs. + * + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device + * dev, NULL if no GPIO has been assigned to the requested function, or + * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, const char *con_id, @@ -4339,16 +4413,15 @@ struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, } EXPORT_SYMBOL_GPL(gpiod_get_optional); - /** * gpiod_configure_flags - helper function to configure a given GPIO - * @desc: gpio whose value will be assigned + * @desc: GPIO whose value will be assigned * @con_id: function within the GPIO consumer - * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from - * of_find_gpio() or of_get_gpio_hog() + * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from *_find_gpio() * @dflags: gpiod_flags - optional GPIO initialization flags * - * Return 0 on success, -ENOENT if no GPIO has been assigned to the + * Returns: + * 0 on success, -ENOENT if no GPIO has been assigned to the * requested function and/or index, or another IS_ERR() code if an error * occurred while trying to acquire the GPIO. */ @@ -4423,7 +4496,8 @@ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, * This variant of gpiod_get() allows to access GPIOs other than the first * defined one for functions that define several GPIOs. * - * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the + * Returns: + * A valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the * requested function and/or index, or another IS_ERR() code if an error * occurred while trying to acquire the GPIO. */ @@ -4451,6 +4525,11 @@ EXPORT_SYMBOL_GPL(gpiod_get_index); * This is equivalent to gpiod_get_index(), except that when no GPIO with the * specified index was assigned to the requested function it will return NULL. * This is convenient for drivers that need to handle optional GPIOs. + * + * Returns: + * A valid GPIO descriptor, NULL if no GPIO has been assigned to the + * requested function and/or index, or another IS_ERR() code if an error + * occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, const char *con_id, @@ -4469,11 +4548,13 @@ EXPORT_SYMBOL_GPL(gpiod_get_index_optional); /** * gpiod_hog - Hog the specified GPIO desc given the provided flags - * @desc: gpio whose value will be assigned + * @desc: GPIO whose value will be assigned * @name: gpio line name - * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from - * of_find_gpio() or of_get_gpio_hog() + * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from *_find_gpio() * @dflags: gpiod_flags - optional GPIO initialization flags + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_hog(struct gpio_desc *desc, const char *name, unsigned long lflags, enum gpiod_flags dflags) @@ -4512,7 +4593,7 @@ int gpiod_hog(struct gpio_desc *desc, const char *name, /** * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog - * @gc: gpio chip to act on + * @gc: GPIO chip to act on */ static void gpiochip_free_hogs(struct gpio_chip *gc) { @@ -4530,9 +4611,11 @@ static void gpiochip_free_hogs(struct gpio_chip *gc) * * This function acquires all the GPIOs defined under a given function. * - * Return a struct gpio_descs containing an array of descriptors, -ENOENT if - * no GPIO has been assigned to the requested function, or another IS_ERR() - * code if an error occurred while trying to acquire the GPIOs. + * Returns: + * The GPIO descriptors corresponding to the function @con_id of device + * dev, -ENOENT if no GPIO has been assigned to the requested function, + * or another IS_ERR() code if an error occurred while trying to acquire + * the GPIOs. */ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, const char *con_id, @@ -4658,6 +4741,12 @@ EXPORT_SYMBOL_GPL(gpiod_get_array); * * This is equivalent to gpiod_get_array(), except that when no GPIO was * assigned to the requested function it will return NULL. + * + * Returns: + * The GPIO descriptors corresponding to the function @con_id of device + * dev, NULL if no GPIO has been assigned to the requested function, + * or another IS_ERR() code if an error occurred while trying to acquire + * the GPIOs. */ struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, const char *con_id, diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index 7f94580efdbc..cb950a3384e3 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -28,7 +28,7 @@ * @mockdev: class device used by the deprecated sysfs interface (may be * NULL) * @owner: helps prevent removal of modules exporting active GPIOs - * @chip: pointer to the corresponding gpiochip, holding static + * @chip: pointer to the corresponding struct gpio_chip, holding static * data for this device * @descs: array of ngpio descriptors. * @ngpio: the number of GPIO lines on this GPIO device, equal to the size @@ -73,10 +73,10 @@ struct gpio_device { #ifdef CONFIG_PINCTRL /* - * If CONFIG_PINCTRL is enabled, then gpio controllers can optionally + * If CONFIG_PINCTRL is enabled, then GPIO chips can optionally * describe the actual pin range which they serve in an SoC. This * information would be used by pinctrl subsystem to configure - * corresponding pins for gpio usage. + * corresponding pins for GPIO usage. */ struct list_head pin_ranges; #endif @@ -240,7 +240,7 @@ int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev); const char *gpiod_get_label(struct gpio_desc *desc); /* - * Return the GPIO number of the passed descriptor relative to its chip + * Return the GPIO number of the passed descriptor relative to its chip. */ static inline int gpio_chip_hwgpio(const struct gpio_desc *desc) {

[v1,2/2] gpiolib: Up to date the kernel documentation

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