| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/spinlock.h> |
| #include <linux/list.h> |
| #include <linux/device.h> |
| #include <linux/err.h> |
| #include <linux/debugfs.h> |
| #include <linux/seq_file.h> |
| #include <linux/gpio.h> |
| #include <linux/of_gpio.h> |
| #include <linux/idr.h> |
| #include <linux/slab.h> |
| #include <linux/acpi.h> |
| #include <linux/gpio/driver.h> |
| #include <linux/gpio/machine.h> |
| |
| #include "gpiolib.h" |
| |
| #define CREATE_TRACE_POINTS |
| #include <trace/events/gpio.h> |
| |
| /* 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 |
| * GPIOs can sometimes cost only an instruction or two per bit. |
| */ |
| |
| |
| /* When debugging, extend minimal trust to callers and platform code. |
| * Also emit diagnostic messages that may help initial bringup, when |
| * board setup or driver bugs are most common. |
| * |
| * Otherwise, minimize overhead in what may be bitbanging codepaths. |
| */ |
| #ifdef DEBUG |
| #define extra_checks 1 |
| #else |
| #define extra_checks 0 |
| #endif |
| |
| /* gpio_lock prevents conflicts during gpio_desc[] table updates. |
| * While any GPIO is requested, its gpio_chip is not removable; |
| * each GPIO's "requested" flag serves as a lock and refcount. |
| */ |
| DEFINE_SPINLOCK(gpio_lock); |
| |
| #define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio) |
| |
| static DEFINE_MUTEX(gpio_lookup_lock); |
| static LIST_HEAD(gpio_lookup_list); |
| LIST_HEAD(gpio_chips); |
| |
| static inline void desc_set_label(struct gpio_desc *d, const char *label) |
| { |
| d->label = label; |
| } |
| |
| /** |
| * Convert a GPIO number to its descriptor |
| */ |
| struct gpio_desc *gpio_to_desc(unsigned gpio) |
| { |
| struct gpio_chip *chip; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| list_for_each_entry(chip, &gpio_chips, list) { |
| if (chip->base <= gpio && chip->base + chip->ngpio > gpio) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return &chip->desc[gpio - chip->base]; |
| } |
| } |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| if (!gpio_is_valid(gpio)) |
| WARN(1, "invalid GPIO %d\n", gpio); |
| |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL(gpio_to_desc); |
| |
| /** |
| * Get the GPIO descriptor corresponding to the given hw number for this chip. |
| */ |
| struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, |
| u16 hwnum) |
| { |
| if (hwnum >= chip->ngpio) |
| return ERR_PTR(-EINVAL); |
| |
| return &chip->desc[hwnum]; |
| } |
| |
| /** |
| * Convert a GPIO descriptor to the integer namespace. |
| * This should disappear in the future but is needed since we still |
| * use GPIO numbers for error messages and sysfs nodes |
| */ |
| int desc_to_gpio(const struct gpio_desc *desc) |
| { |
| return desc->chip->base + (desc - &desc->chip->desc[0]); |
| } |
| 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 |
| */ |
| struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) |
| { |
| return desc ? desc->chip : NULL; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_to_chip); |
| |
| /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ |
| static int gpiochip_find_base(int ngpio) |
| { |
| struct gpio_chip *chip; |
| int base = ARCH_NR_GPIOS - ngpio; |
| |
| list_for_each_entry_reverse(chip, &gpio_chips, list) { |
| /* found a free space? */ |
| if (chip->base + chip->ngpio <= base) |
| break; |
| else |
| /* nope, check the space right before the chip */ |
| base = chip->base - ngpio; |
| } |
| |
| if (gpio_is_valid(base)) { |
| pr_debug("%s: found new base at %d\n", __func__, base); |
| return base; |
| } else { |
| pr_err("%s: cannot find free range\n", __func__); |
| return -ENOSPC; |
| } |
| } |
| |
| /** |
| * gpiod_get_direction - return the current direction of a GPIO |
| * @desc: GPIO to get the direction of |
| * |
| * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. |
| * |
| * This function may sleep if gpiod_cansleep() is true. |
| */ |
| int gpiod_get_direction(struct gpio_desc *desc) |
| { |
| struct gpio_chip *chip; |
| unsigned offset; |
| int status = -EINVAL; |
| |
| chip = gpiod_to_chip(desc); |
| offset = gpio_chip_hwgpio(desc); |
| |
| if (!chip->get_direction) |
| return status; |
| |
| status = chip->get_direction(chip, offset); |
| if (status > 0) { |
| /* GPIOF_DIR_IN, or other positive */ |
| status = 1; |
| clear_bit(FLAG_IS_OUT, &desc->flags); |
| } |
| if (status == 0) { |
| /* GPIOF_DIR_OUT */ |
| set_bit(FLAG_IS_OUT, &desc->flags); |
| } |
| return status; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_get_direction); |
| |
| /* |
| * Add a new chip to the global chips list, keeping the list of chips sorted |
| * by base order. |
| * |
| * Return -EBUSY if the new chip overlaps with some other chip's integer |
| * space. |
| */ |
| static int gpiochip_add_to_list(struct gpio_chip *chip) |
| { |
| struct list_head *pos = &gpio_chips; |
| struct gpio_chip *_chip; |
| int err = 0; |
| |
| /* find where to insert our chip */ |
| list_for_each(pos, &gpio_chips) { |
| _chip = list_entry(pos, struct gpio_chip, list); |
| /* shall we insert before _chip? */ |
| if (_chip->base >= chip->base + chip->ngpio) |
| break; |
| } |
| |
| /* are we stepping on the chip right before? */ |
| if (pos != &gpio_chips && pos->prev != &gpio_chips) { |
| _chip = list_entry(pos->prev, struct gpio_chip, list); |
| if (_chip->base + _chip->ngpio > chip->base) { |
| dev_err(chip->dev, |
| "GPIO integer space overlap, cannot add chip\n"); |
| err = -EBUSY; |
| } |
| } |
| |
| if (!err) |
| list_add_tail(&chip->list, pos); |
| |
| return err; |
| } |
| |
| /** |
| * gpiochip_add() - register a gpio_chip |
| * @chip: the chip to register, with chip->base initialized |
| * Context: potentially before irqs will work |
| * |
| * Returns a negative errno if the chip can't be registered, such as |
| * because the chip->base is invalid or already associated with a |
| * different chip. Otherwise it returns zero as a success code. |
| * |
| * When gpiochip_add() is called very early during boot, so that GPIOs |
| * can be freely used, the chip->dev device must be registered before |
| * the gpio framework's arch_initcall(). Otherwise sysfs initialization |
| * for GPIOs will fail rudely. |
| * |
| * If chip->base is negative, this requests dynamic assignment of |
| * a range of valid GPIOs. |
| */ |
| int gpiochip_add(struct gpio_chip *chip) |
| { |
| unsigned long flags; |
| int status = 0; |
| unsigned id; |
| int base = chip->base; |
| struct gpio_desc *descs; |
| |
| descs = kcalloc(chip->ngpio, sizeof(descs[0]), GFP_KERNEL); |
| if (!descs) |
| return -ENOMEM; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| if (base < 0) { |
| base = gpiochip_find_base(chip->ngpio); |
| if (base < 0) { |
| status = base; |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| goto err_free_descs; |
| } |
| chip->base = base; |
| } |
| |
| status = gpiochip_add_to_list(chip); |
| if (status) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| goto err_free_descs; |
| } |
| |
| for (id = 0; id < chip->ngpio; id++) { |
| struct gpio_desc *desc = &descs[id]; |
| |
| desc->chip = chip; |
| |
| /* REVISIT: most hardware initializes GPIOs as inputs (often |
| * with pullups enabled) so power usage is minimized. Linux |
| * code should set the gpio direction first thing; but until |
| * it does, and in case chip->get_direction is not set, we may |
| * expose the wrong direction in sysfs. |
| */ |
| desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0; |
| } |
| |
| chip->desc = descs; |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| #ifdef CONFIG_PINCTRL |
| INIT_LIST_HEAD(&chip->pin_ranges); |
| #endif |
| |
| of_gpiochip_add(chip); |
| acpi_gpiochip_add(chip); |
| |
| status = gpiochip_export(chip); |
| if (status) |
| goto err_remove_chip; |
| |
| pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__, |
| chip->base, chip->base + chip->ngpio - 1, |
| chip->label ? : "generic"); |
| |
| return 0; |
| |
| err_remove_chip: |
| acpi_gpiochip_remove(chip); |
| of_gpiochip_remove(chip); |
| spin_lock_irqsave(&gpio_lock, flags); |
| list_del(&chip->list); |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| chip->desc = NULL; |
| err_free_descs: |
| kfree(descs); |
| |
| /* failures here can mean systems won't boot... */ |
| pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
| chip->base, chip->base + chip->ngpio - 1, |
| chip->label ? : "generic"); |
| return status; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_add); |
| |
| /* Forward-declaration */ |
| static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); |
| |
| /** |
| * gpiochip_remove() - unregister a gpio_chip |
| * @chip: the chip to unregister |
| * |
| * A gpio_chip with any GPIOs still requested may not be removed. |
| */ |
| void gpiochip_remove(struct gpio_chip *chip) |
| { |
| unsigned long flags; |
| unsigned id; |
| |
| gpiochip_irqchip_remove(chip); |
| |
| acpi_gpiochip_remove(chip); |
| gpiochip_remove_pin_ranges(chip); |
| of_gpiochip_remove(chip); |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| for (id = 0; id < chip->ngpio; id++) { |
| if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) |
| dev_crit(chip->dev, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); |
| } |
| for (id = 0; id < chip->ngpio; id++) |
| chip->desc[id].chip = NULL; |
| |
| list_del(&chip->list); |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| gpiochip_unexport(chip); |
| |
| kfree(chip->desc); |
| chip->desc = NULL; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_remove); |
| |
| /** |
| * gpiochip_find() - iterator for locating a specific gpio_chip |
| * @data: data to pass to match function |
| * @callback: Callback function to check gpio_chip |
| * |
| * Similar to bus_find_device. It returns a reference to a gpio_chip as |
| * determined by a user supplied @match callback. The callback should return |
| * 0 if the device doesn't match and non-zero if it does. If the callback is |
| * non-zero, this function will return to the caller and not iterate over any |
| * more gpio_chips. |
| */ |
| struct gpio_chip *gpiochip_find(void *data, |
| int (*match)(struct gpio_chip *chip, |
| void *data)) |
| { |
| struct gpio_chip *chip; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| list_for_each_entry(chip, &gpio_chips, list) |
| if (match(chip, data)) |
| break; |
| |
| /* No match? */ |
| if (&chip->list == &gpio_chips) |
| chip = NULL; |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| return chip; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_find); |
| |
| static int gpiochip_match_name(struct gpio_chip *chip, void *data) |
| { |
| const char *name = data; |
| |
| return !strcmp(chip->label, name); |
| } |
| |
| static struct gpio_chip *find_chip_by_name(const char *name) |
| { |
| return gpiochip_find((void *)name, gpiochip_match_name); |
| } |
| |
| #ifdef CONFIG_GPIOLIB_IRQCHIP |
| |
| /* |
| * The following is irqchip helper code for gpiochips. |
| */ |
| |
| /** |
| * gpiochip_set_chained_irqchip() - sets a chained irqchip to a gpiochip |
| * @gpiochip: the gpiochip to set the irqchip chain to |
| * @irqchip: the irqchip to chain to the gpiochip |
| * @parent_irq: the irq number corresponding to the parent IRQ for this |
| * chained irqchip |
| * @parent_handler: the parent interrupt handler for the accumulated IRQ |
| * coming out of the gpiochip. If the interrupt is nested rather than |
| * cascaded, pass NULL in this handler argument |
| */ |
| void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, |
| struct irq_chip *irqchip, |
| int parent_irq, |
| irq_flow_handler_t parent_handler) |
| { |
| unsigned int offset; |
| |
| if (!gpiochip->irqdomain) { |
| chip_err(gpiochip, "called %s before setting up irqchip\n", |
| __func__); |
| return; |
| } |
| |
| if (parent_handler) { |
| if (gpiochip->can_sleep) { |
| chip_err(gpiochip, |
| "you cannot have chained interrupts on a " |
| "chip that may sleep\n"); |
| return; |
| } |
| /* |
| * The parent irqchip is already using the chip_data for this |
| * irqchip, so our callbacks simply use the handler_data. |
| */ |
| irq_set_handler_data(parent_irq, gpiochip); |
| irq_set_chained_handler(parent_irq, parent_handler); |
| } |
| |
| /* Set the parent IRQ for all affected IRQs */ |
| for (offset = 0; offset < gpiochip->ngpio; offset++) |
| irq_set_parent(irq_find_mapping(gpiochip->irqdomain, offset), |
| parent_irq); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); |
| |
| /* |
| * This lock class tells lockdep that GPIO irqs are in a different |
| * category than their parents, so it won't report false recursion. |
| */ |
| static struct lock_class_key gpiochip_irq_lock_class; |
| |
| /** |
| * 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 |
| * |
| * 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. |
| */ |
| static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, |
| irq_hw_number_t hwirq) |
| { |
| struct gpio_chip *chip = d->host_data; |
| |
| irq_set_chip_data(irq, chip); |
| irq_set_lockdep_class(irq, &gpiochip_irq_lock_class); |
| irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); |
| /* Chips that can sleep need nested thread handlers */ |
| if (chip->can_sleep && !chip->irq_not_threaded) |
| irq_set_nested_thread(irq, 1); |
| #ifdef CONFIG_ARM |
| set_irq_flags(irq, IRQF_VALID); |
| #else |
| irq_set_noprobe(irq); |
| #endif |
| /* |
| * No set-up of the hardware will happen if IRQ_TYPE_NONE |
| * is passed as default type. |
| */ |
| if (chip->irq_default_type != IRQ_TYPE_NONE) |
| irq_set_irq_type(irq, chip->irq_default_type); |
| |
| return 0; |
| } |
| |
| static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) |
| { |
| struct gpio_chip *chip = d->host_data; |
| |
| #ifdef CONFIG_ARM |
| set_irq_flags(irq, 0); |
| #endif |
| if (chip->can_sleep) |
| irq_set_nested_thread(irq, 0); |
| irq_set_chip_and_handler(irq, NULL, NULL); |
| irq_set_chip_data(irq, NULL); |
| } |
| |
| static const struct irq_domain_ops gpiochip_domain_ops = { |
| .map = gpiochip_irq_map, |
| .unmap = gpiochip_irq_unmap, |
| /* Virtually all GPIO irqchips are twocell:ed */ |
| .xlate = irq_domain_xlate_twocell, |
| }; |
| |
| static int gpiochip_irq_reqres(struct irq_data *d) |
| { |
| struct gpio_chip *chip = irq_data_get_irq_chip_data(d); |
| |
| if (gpiochip_lock_as_irq(chip, d->hwirq)) { |
| chip_err(chip, |
| "unable to lock HW IRQ %lu for IRQ\n", |
| d->hwirq); |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static void gpiochip_irq_relres(struct irq_data *d) |
| { |
| struct gpio_chip *chip = irq_data_get_irq_chip_data(d); |
| |
| gpiochip_unlock_as_irq(chip, d->hwirq); |
| } |
| |
| static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) |
| { |
| return irq_find_mapping(chip->irqdomain, offset); |
| } |
| |
| /** |
| * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip |
| * @gpiochip: the gpiochip to remove the irqchip from |
| * |
| * This is called only from gpiochip_remove() |
| */ |
| static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) |
| { |
| unsigned int offset; |
| |
| acpi_gpiochip_free_interrupts(gpiochip); |
| |
| /* Remove all IRQ mappings and delete the domain */ |
| if (gpiochip->irqdomain) { |
| for (offset = 0; offset < gpiochip->ngpio; offset++) |
| irq_dispose_mapping( |
| irq_find_mapping(gpiochip->irqdomain, offset)); |
| irq_domain_remove(gpiochip->irqdomain); |
| } |
| |
| if (gpiochip->irqchip) { |
| gpiochip->irqchip->irq_request_resources = NULL; |
| gpiochip->irqchip->irq_release_resources = NULL; |
| gpiochip->irqchip = NULL; |
| } |
| } |
| |
| /** |
| * gpiochip_irqchip_add() - adds an irqchip to a gpiochip |
| * @gpiochip: the gpiochip to add the irqchip to |
| * @irqchip: the irqchip to add to the gpiochip |
| * @first_irq: if not dynamically assigned, the base (first) IRQ to |
| * allocate gpiochip irqs from |
| * @handler: the irq handler to use (often a predefined irq core function) |
| * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE |
| * to have the core avoid setting up any default type in the hardware. |
| * |
| * This function closely associates a certain irqchip with a certain |
| * gpiochip, providing an irq domain to translate the local IRQs to |
| * global irqs in the gpiolib core, and making sure that the gpiochip |
| * is passed as chip data to all related functions. Driver callbacks |
| * need to use container_of() to get their local state containers back |
| * from the gpiochip passed as chip data. An irqdomain will be stored |
| * in the gpiochip that shall be used by the driver to handle IRQ number |
| * translation. The gpiochip will need to be initialized and registered |
| * before calling this function. |
| * |
| * This function will handle two cell:ed simple IRQs and assumes all |
| * the pins on the gpiochip can generate a unique IRQ. Everything else |
| * need to be open coded. |
| */ |
| int gpiochip_irqchip_add(struct gpio_chip *gpiochip, |
| struct irq_chip *irqchip, |
| unsigned int first_irq, |
| irq_flow_handler_t handler, |
| unsigned int type) |
| { |
| struct device_node *of_node; |
| unsigned int offset; |
| unsigned irq_base = 0; |
| |
| if (!gpiochip || !irqchip) |
| return -EINVAL; |
| |
| if (!gpiochip->dev) { |
| pr_err("missing gpiochip .dev parent pointer\n"); |
| return -EINVAL; |
| } |
| of_node = gpiochip->dev->of_node; |
| #ifdef CONFIG_OF_GPIO |
| /* |
| * If the gpiochip has an assigned OF node this takes precendence |
| * FIXME: get rid of this and use gpiochip->dev->of_node everywhere |
| */ |
| if (gpiochip->of_node) |
| of_node = gpiochip->of_node; |
| #endif |
| gpiochip->irqchip = irqchip; |
| gpiochip->irq_handler = handler; |
| gpiochip->irq_default_type = type; |
| gpiochip->to_irq = gpiochip_to_irq; |
| gpiochip->irqdomain = irq_domain_add_simple(of_node, |
| gpiochip->ngpio, first_irq, |
| &gpiochip_domain_ops, gpiochip); |
| if (!gpiochip->irqdomain) { |
| gpiochip->irqchip = NULL; |
| return -EINVAL; |
| } |
| irqchip->irq_request_resources = gpiochip_irq_reqres; |
| irqchip->irq_release_resources = gpiochip_irq_relres; |
| |
| /* |
| * Prepare the mapping since the irqchip shall be orthogonal to |
| * any gpiochip calls. If the first_irq was zero, this is |
| * necessary to allocate descriptors for all IRQs. |
| */ |
| for (offset = 0; offset < gpiochip->ngpio; offset++) { |
| irq_base = irq_create_mapping(gpiochip->irqdomain, offset); |
| if (offset == 0) |
| /* |
| * Store the base into the gpiochip to be used when |
| * unmapping the irqs. |
| */ |
| gpiochip->irq_base = irq_base; |
| } |
| |
| acpi_gpiochip_request_interrupts(gpiochip); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_irqchip_add); |
| |
| #else /* CONFIG_GPIOLIB_IRQCHIP */ |
| |
| static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} |
| |
| #endif /* CONFIG_GPIOLIB_IRQCHIP */ |
| |
| #ifdef CONFIG_PINCTRL |
| |
| /** |
| * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping |
| * @chip: the gpiochip to add the range for |
| * @pinctrl: the dev_name() of the pin controller to map to |
| * @gpio_offset: the start offset in the current gpio_chip number space |
| * @pin_group: name of the pin group inside the pin controller |
| */ |
| int gpiochip_add_pingroup_range(struct gpio_chip *chip, |
| struct pinctrl_dev *pctldev, |
| unsigned int gpio_offset, const char *pin_group) |
| { |
| struct gpio_pin_range *pin_range; |
| int ret; |
| |
| pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
| if (!pin_range) { |
| chip_err(chip, "failed to allocate pin ranges\n"); |
| return -ENOMEM; |
| } |
| |
| /* Use local offset as range ID */ |
| pin_range->range.id = gpio_offset; |
| pin_range->range.gc = chip; |
| pin_range->range.name = chip->label; |
| pin_range->range.base = chip->base + gpio_offset; |
| pin_range->pctldev = pctldev; |
| |
| ret = pinctrl_get_group_pins(pctldev, pin_group, |
| &pin_range->range.pins, |
| &pin_range->range.npins); |
| if (ret < 0) { |
| kfree(pin_range); |
| return ret; |
| } |
| |
| pinctrl_add_gpio_range(pctldev, &pin_range->range); |
| |
| chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", |
| gpio_offset, gpio_offset + pin_range->range.npins - 1, |
| pinctrl_dev_get_devname(pctldev), pin_group); |
| |
| list_add_tail(&pin_range->node, &chip->pin_ranges); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); |
| |
| /** |
| * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping |
| * @chip: the gpiochip to add the range for |
| * @pinctrl_name: the dev_name() of the pin controller to map to |
| * @gpio_offset: the start offset in the current gpio_chip 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 |
| */ |
| int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, |
| unsigned int gpio_offset, unsigned int pin_offset, |
| unsigned int npins) |
| { |
| struct gpio_pin_range *pin_range; |
| int ret; |
| |
| pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); |
| if (!pin_range) { |
| chip_err(chip, "failed to allocate pin ranges\n"); |
| return -ENOMEM; |
| } |
| |
| /* Use local offset as range ID */ |
| pin_range->range.id = gpio_offset; |
| pin_range->range.gc = chip; |
| pin_range->range.name = chip->label; |
| pin_range->range.base = chip->base + gpio_offset; |
| pin_range->range.pin_base = pin_offset; |
| pin_range->range.npins = npins; |
| pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, |
| &pin_range->range); |
| if (IS_ERR(pin_range->pctldev)) { |
| ret = PTR_ERR(pin_range->pctldev); |
| chip_err(chip, "could not create pin range\n"); |
| kfree(pin_range); |
| return ret; |
| } |
| chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", |
| gpio_offset, gpio_offset + npins - 1, |
| pinctl_name, |
| pin_offset, pin_offset + npins - 1); |
| |
| list_add_tail(&pin_range->node, &chip->pin_ranges); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); |
| |
| /** |
| * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings |
| * @chip: the chip to remove all the mappings for |
| */ |
| void gpiochip_remove_pin_ranges(struct gpio_chip *chip) |
| { |
| struct gpio_pin_range *pin_range, *tmp; |
| |
| list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { |
| list_del(&pin_range->node); |
| pinctrl_remove_gpio_range(pin_range->pctldev, |
| &pin_range->range); |
| kfree(pin_range); |
| } |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); |
| |
| #endif /* CONFIG_PINCTRL */ |
| |
| /* 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. |
| */ |
| static int __gpiod_request(struct gpio_desc *desc, const char *label) |
| { |
| struct gpio_chip *chip = desc->chip; |
| int status; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| /* NOTE: gpio_request() can be called in early boot, |
| * before IRQs are enabled, for non-sleeping (SOC) GPIOs. |
| */ |
| |
| if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { |
| desc_set_label(desc, label ? : "?"); |
| status = 0; |
| } else { |
| status = -EBUSY; |
| goto done; |
| } |
| |
| if (chip->request) { |
| /* chip->request may sleep */ |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| status = chip->request(chip, gpio_chip_hwgpio(desc)); |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| if (status < 0) { |
| desc_set_label(desc, NULL); |
| clear_bit(FLAG_REQUESTED, &desc->flags); |
| goto done; |
| } |
| } |
| if (chip->get_direction) { |
| /* chip->get_direction may sleep */ |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| gpiod_get_direction(desc); |
| spin_lock_irqsave(&gpio_lock, flags); |
| } |
| done: |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return status; |
| } |
| |
| int gpiod_request(struct gpio_desc *desc, const char *label) |
| { |
| int status = -EPROBE_DEFER; |
| struct gpio_chip *chip; |
| |
| if (!desc) { |
| pr_warn("%s: invalid GPIO\n", __func__); |
| return -EINVAL; |
| } |
| |
| chip = desc->chip; |
| if (!chip) |
| goto done; |
| |
| if (try_module_get(chip->owner)) { |
| status = __gpiod_request(desc, label); |
| if (status < 0) |
| module_put(chip->owner); |
| } |
| |
| done: |
| if (status) |
| gpiod_dbg(desc, "%s: status %d\n", __func__, status); |
| |
| return status; |
| } |
| |
| static bool __gpiod_free(struct gpio_desc *desc) |
| { |
| bool ret = false; |
| unsigned long flags; |
| struct gpio_chip *chip; |
| |
| might_sleep(); |
| |
| gpiod_unexport(desc); |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| chip = desc->chip; |
| if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { |
| if (chip->free) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| might_sleep_if(chip->can_sleep); |
| chip->free(chip, gpio_chip_hwgpio(desc)); |
| spin_lock_irqsave(&gpio_lock, flags); |
| } |
| desc_set_label(desc, NULL); |
| clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| clear_bit(FLAG_REQUESTED, &desc->flags); |
| clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
| clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
| ret = true; |
| } |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return ret; |
| } |
| |
| void gpiod_free(struct gpio_desc *desc) |
| { |
| if (desc && __gpiod_free(desc)) |
| module_put(desc->chip->owner); |
| else |
| WARN_ON(extra_checks); |
| } |
| |
| /** |
| * gpiochip_is_requested - return string iff signal was requested |
| * @chip: controller managing the signal |
| * @offset: of signal within controller's 0..(ngpio - 1) range |
| * |
| * Returns NULL if the GPIO is not currently requested, else a string. |
| * The string returned is the label passed to gpio_request(); if none has been |
| * passed it is a meaningless, non-NULL constant. |
| * |
| * This function is for use by GPIO controller drivers. The label can |
| * help with diagnostics, and knowing that the signal is used as a GPIO |
| * can help avoid accidentally multiplexing it to another controller. |
| */ |
| const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) |
| { |
| struct gpio_desc *desc; |
| |
| if (!GPIO_OFFSET_VALID(chip, offset)) |
| return NULL; |
| |
| desc = &chip->desc[offset]; |
| |
| if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) |
| return NULL; |
| return desc->label; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_is_requested); |
| |
| /** |
| * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor |
| * @desc: GPIO descriptor to request |
| * @label: label for the GPIO |
| * |
| * Function allows GPIO chip drivers to request and use their own GPIO |
| * descriptors via gpiolib API. Difference to gpiod_request() is that this |
| * function will not increase reference count of the GPIO chip module. This |
| * allows the GPIO chip module to be unloaded as needed (we assume that the |
| * GPIO chip driver handles freeing the GPIOs it has requested). |
| */ |
| struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, |
| const char *label) |
| { |
| struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum); |
| int err; |
| |
| if (IS_ERR(desc)) { |
| chip_err(chip, "failed to get GPIO descriptor\n"); |
| return desc; |
| } |
| |
| err = __gpiod_request(desc, label); |
| if (err < 0) |
| return ERR_PTR(err); |
| |
| return desc; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); |
| |
| /** |
| * gpiochip_free_own_desc - Free GPIO requested by the chip driver |
| * @desc: GPIO descriptor to free |
| * |
| * Function frees the given GPIO requested previously with |
| * gpiochip_request_own_desc(). |
| */ |
| void gpiochip_free_own_desc(struct gpio_desc *desc) |
| { |
| if (desc) |
| __gpiod_free(desc); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); |
| |
| /* Drivers MUST set GPIO direction before making get/set calls. In |
| * some cases this is done in early boot, before IRQs are enabled. |
| * |
| * 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) |
| * rely on gpio_request() having been called beforehand. |
| */ |
| |
| /** |
| * gpiod_direction_input - set the GPIO direction to input |
| * @desc: GPIO to set to input |
| * |
| * 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. |
| */ |
| int gpiod_direction_input(struct gpio_desc *desc) |
| { |
| struct gpio_chip *chip; |
| int status = -EINVAL; |
| |
| if (!desc || !desc->chip) { |
| pr_warn("%s: invalid GPIO\n", __func__); |
| return -EINVAL; |
| } |
| |
| chip = desc->chip; |
| if (!chip->get || !chip->direction_input) { |
| gpiod_warn(desc, |
| "%s: missing get() or direction_input() operations\n", |
| __func__); |
| return -EIO; |
| } |
| |
| status = chip->direction_input(chip, gpio_chip_hwgpio(desc)); |
| if (status == 0) |
| clear_bit(FLAG_IS_OUT, &desc->flags); |
| |
| trace_gpio_direction(desc_to_gpio(desc), 1, status); |
| |
| return status; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_direction_input); |
| |
| static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
| { |
| struct gpio_chip *chip; |
| int status = -EINVAL; |
| |
| /* GPIOs used for IRQs shall not be set as output */ |
| if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { |
| gpiod_err(desc, |
| "%s: tried to set a GPIO tied to an IRQ as output\n", |
| __func__); |
| return -EIO; |
| } |
| |
| /* Open drain pin should not be driven to 1 */ |
| if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) |
| return gpiod_direction_input(desc); |
| |
| /* Open source pin should not be driven to 0 */ |
| if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) |
| return gpiod_direction_input(desc); |
| |
| chip = desc->chip; |
| if (!chip->set || !chip->direction_output) { |
| gpiod_warn(desc, |
| "%s: missing set() or direction_output() operations\n", |
| __func__); |
| return -EIO; |
| } |
| |
| status = chip->direction_output(chip, gpio_chip_hwgpio(desc), value); |
| if (status == 0) |
| set_bit(FLAG_IS_OUT, &desc->flags); |
| trace_gpio_value(desc_to_gpio(desc), 0, value); |
| trace_gpio_direction(desc_to_gpio(desc), 0, status); |
| return status; |
| } |
| |
| /** |
| * gpiod_direction_output_raw - set the GPIO direction to output |
| * @desc: GPIO to set to output |
| * @value: initial output value of the GPIO |
| * |
| * Set the direction of the passed GPIO to output, such as gpiod_set_value() can |
| * 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. |
| */ |
| int gpiod_direction_output_raw(struct gpio_desc *desc, int value) |
| { |
| if (!desc || !desc->chip) { |
| pr_warn("%s: invalid GPIO\n", __func__); |
| return -EINVAL; |
| } |
| return _gpiod_direction_output_raw(desc, value); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); |
| |
| /** |
| * gpiod_direction_output - set the GPIO direction to output |
| * @desc: GPIO to set to output |
| * @value: initial output value of the GPIO |
| * |
| * Set the direction of the passed GPIO to output, such as gpiod_set_value() can |
| * be called safely on it. The initial value of the output must be specified |
| * 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. |
| */ |
| int gpiod_direction_output(struct gpio_desc *desc, int value) |
| { |
| if (!desc || !desc->chip) { |
| pr_warn("%s: invalid GPIO\n", __func__); |
| return -EINVAL; |
| } |
| if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| value = !value; |
| return _gpiod_direction_output_raw(desc, value); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_direction_output); |
| |
| /** |
| * gpiod_set_debounce - sets @debounce time for a @gpio |
| * @gpio: the gpio to set debounce time |
| * @debounce: debounce time is microseconds |
| * |
| * returns -ENOTSUPP if the controller does not support setting |
| * debounce. |
| */ |
| int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) |
| { |
| struct gpio_chip *chip; |
| |
| if (!desc || !desc->chip) { |
| pr_warn("%s: invalid GPIO\n", __func__); |
| return -EINVAL; |
| } |
| |
| chip = desc->chip; |
| if (!chip->set || !chip->set_debounce) { |
| gpiod_dbg(desc, |
| "%s: missing set() or set_debounce() operations\n", |
| __func__); |
| return -ENOTSUPP; |
| } |
| |
| return chip->set_debounce(chip, gpio_chip_hwgpio(desc), debounce); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_debounce); |
| |
| /** |
| * gpiod_is_active_low - test whether a GPIO is active-low or not |
| * @desc: the gpio descriptor to test |
| * |
| * Returns 1 if the GPIO is active-low, 0 otherwise. |
| */ |
| int gpiod_is_active_low(const struct gpio_desc *desc) |
| { |
| return test_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_is_active_low); |
| |
| /* 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, |
| * and masking the relevant bit in that register. |
| * |
| * When "set" operations are inlinable, they involve writing that mask to |
| * one register to set a low value, or a different register to set it high. |
| * Otherwise locking is needed, so there may be little value to inlining. |
| * |
| *------------------------------------------------------------------------ |
| * |
| * 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 |
| * in memory, guaranteeing that these table lookups need no more locking |
| * and that gpiochip_remove() will fail. |
| * |
| * REVISIT when debugging, consider adding some instrumentation to ensure |
| * that the GPIO was actually requested. |
| */ |
| |
| static bool _gpiod_get_raw_value(const struct gpio_desc *desc) |
| { |
| struct gpio_chip *chip; |
| bool value; |
| int offset; |
| |
| chip = desc->chip; |
| offset = gpio_chip_hwgpio(desc); |
| value = chip->get ? chip->get(chip, offset) : false; |
| trace_gpio_value(desc_to_gpio(desc), 1, value); |
| return value; |
| } |
| |
| /** |
| * 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 |
| * its ACTIVE_LOW status. |
| * |
| * This function should be called from contexts where we cannot sleep, and will |
| * complain if the GPIO chip functions potentially sleep. |
| */ |
| int gpiod_get_raw_value(const struct gpio_desc *desc) |
| { |
| if (!desc) |
| return 0; |
| /* Should be using gpio_get_value_cansleep() */ |
| WARN_ON(desc->chip->can_sleep); |
| return _gpiod_get_raw_value(desc); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_get_raw_value); |
| |
| /** |
| * 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 |
| * account. |
| * |
| * This function should be called from contexts where we cannot sleep, and will |
| * complain if the GPIO chip functions potentially sleep. |
| */ |
| int gpiod_get_value(const struct gpio_desc *desc) |
| { |
| int value; |
| if (!desc) |
| return 0; |
| /* Should be using gpio_get_value_cansleep() */ |
| WARN_ON(desc->chip->can_sleep); |
| |
| value = _gpiod_get_raw_value(desc); |
| if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| value = !value; |
| |
| return value; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_get_value); |
| |
| /* |
| * _gpio_set_open_drain_value() - Set the open drain gpio's value. |
| * @desc: gpio descriptor whose state need to be set. |
| * @value: Non-zero for setting it HIGH otherise it will set to LOW. |
| */ |
| static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value) |
| { |
| int err = 0; |
| struct gpio_chip *chip = desc->chip; |
| int offset = gpio_chip_hwgpio(desc); |
| |
| if (value) { |
| err = chip->direction_input(chip, offset); |
| if (!err) |
| clear_bit(FLAG_IS_OUT, &desc->flags); |
| } else { |
| err = chip->direction_output(chip, offset, 0); |
| if (!err) |
| set_bit(FLAG_IS_OUT, &desc->flags); |
| } |
| trace_gpio_direction(desc_to_gpio(desc), value, err); |
| if (err < 0) |
| gpiod_err(desc, |
| "%s: Error in set_value for open drain err %d\n", |
| __func__, err); |
| } |
| |
| /* |
| * _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 otherise it will set to LOW. |
| */ |
| static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value) |
| { |
| int err = 0; |
| struct gpio_chip *chip = desc->chip; |
| int offset = gpio_chip_hwgpio(desc); |
| |
| if (value) { |
| err = chip->direction_output(chip, offset, 1); |
| if (!err) |
| set_bit(FLAG_IS_OUT, &desc->flags); |
| } else { |
| err = chip->direction_input(chip, offset); |
| if (!err) |
| clear_bit(FLAG_IS_OUT, &desc->flags); |
| } |
| trace_gpio_direction(desc_to_gpio(desc), !value, err); |
| if (err < 0) |
| gpiod_err(desc, |
| "%s: Error in set_value for open source err %d\n", |
| __func__, err); |
| } |
| |
| static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value) |
| { |
| struct gpio_chip *chip; |
| |
| chip = desc->chip; |
| trace_gpio_value(desc_to_gpio(desc), 0, value); |
| if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) |
| _gpio_set_open_drain_value(desc, value); |
| else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) |
| _gpio_set_open_source_value(desc, value); |
| else |
| chip->set(chip, gpio_chip_hwgpio(desc), value); |
| } |
| |
| /* |
| * set multiple outputs on the same chip; |
| * use the chip's set_multiple function if available; |
| * otherwise set the outputs sequentially; |
| * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word |
| * defines which outputs are to be changed |
| * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word |
| * defines the values the outputs specified by mask are to be set to |
| */ |
| static void gpio_chip_set_multiple(struct gpio_chip *chip, |
| unsigned long *mask, unsigned long *bits) |
| { |
| if (chip->set_multiple) { |
| chip->set_multiple(chip, mask, bits); |
| } else { |
| int i; |
| for (i = 0; i < chip->ngpio; i++) { |
| if (mask[BIT_WORD(i)] == 0) { |
| /* no more set bits in this mask word; |
| * skip ahead to the next word */ |
| i = (BIT_WORD(i) + 1) * BITS_PER_LONG - 1; |
| continue; |
| } |
| /* set outputs if the corresponding mask bit is set */ |
| if (__test_and_clear_bit(i, mask)) { |
| chip->set(chip, i, test_bit(i, bits)); |
| } |
| } |
| } |
| } |
| |
| static void gpiod_set_array_priv(bool raw, bool can_sleep, |
| unsigned int array_size, |
| struct gpio_desc **desc_array, |
| int *value_array) |
| { |
| int i = 0; |
| |
| while (i < array_size) { |
| struct gpio_chip *chip = desc_array[i]->chip; |
| unsigned long mask[BITS_TO_LONGS(chip->ngpio)]; |
| unsigned long bits[BITS_TO_LONGS(chip->ngpio)]; |
| int count = 0; |
| |
| if (!can_sleep) { |
| WARN_ON(chip->can_sleep); |
| } |
| memset(mask, 0, sizeof(mask)); |
| do { |
| struct gpio_desc *desc = desc_array[i]; |
| int hwgpio = gpio_chip_hwgpio(desc); |
| int value = value_array[i]; |
| |
| if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| value = !value; |
| trace_gpio_value(desc_to_gpio(desc), 0, value); |
| /* |
| * collect all normal outputs belonging to the same chip |
| * open drain and open source outputs are set individually |
| */ |
| if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { |
| _gpio_set_open_drain_value(desc,value); |
| } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { |
| _gpio_set_open_source_value(desc, value); |
| } else { |
| __set_bit(hwgpio, mask); |
| if (value) { |
| __set_bit(hwgpio, bits); |
| } else { |
| __clear_bit(hwgpio, bits); |
| } |
| count++; |
| } |
| i++; |
| } while ((i < array_size) && (desc_array[i]->chip == chip)); |
| /* push collected bits to outputs */ |
| if (count != 0) { |
| gpio_chip_set_multiple(chip, mask, bits); |
| } |
| } |
| } |
| |
| /** |
| * 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 |
| * regard for its ACTIVE_LOW status. |
| * |
| * This function should be called from contexts where we cannot sleep, and will |
| * complain if the GPIO chip functions potentially sleep. |
| */ |
| void gpiod_set_raw_value(struct gpio_desc *desc, int value) |
| { |
| if (!desc) |
| return; |
| /* Should be using gpio_set_value_cansleep() */ |
| WARN_ON(desc->chip->can_sleep); |
| _gpiod_set_raw_value(desc, value); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_raw_value); |
| |
| /** |
| * 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 status into |
| * account |
| * |
| * This function should be called from contexts where we cannot sleep, and will |
| * complain if the GPIO chip functions potentially sleep. |
| */ |
| void gpiod_set_value(struct gpio_desc *desc, int value) |
| { |
| if (!desc) |
| return; |
| /* Should be using gpio_set_value_cansleep() */ |
| WARN_ON(desc->chip->can_sleep); |
| if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| value = !value; |
| _gpiod_set_raw_value(desc, value); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_value); |
| |
| /** |
| * gpiod_set_raw_array() - assign values to an array of GPIOs |
| * @array_size: number of elements in the descriptor / value arrays |
| * @desc_array: array of GPIO descriptors whose values will be assigned |
| * @value_array: array of values to assign |
| * |
| * Set the raw values of the GPIOs, i.e. the values of the physical lines |
| * without regard for their ACTIVE_LOW status. |
| * |
| * This function should be called from contexts where we cannot sleep, and will |
| * complain if the GPIO chip functions potentially sleep. |
| */ |
| void gpiod_set_raw_array(unsigned int array_size, |
| struct gpio_desc **desc_array, int *value_array) |
| { |
| if (!desc_array) |
| return; |
| gpiod_set_array_priv(true, false, array_size, desc_array, value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_raw_array); |
| |
| /** |
| * gpiod_set_array() - assign values to an array of GPIOs |
| * @array_size: number of elements in the descriptor / value arrays |
| * @desc_array: array of GPIO descriptors whose values will be assigned |
| * @value_array: array of values to assign |
| * |
| * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status |
| * into account. |
| * |
| * This function should be called from contexts where we cannot sleep, and will |
| * complain if the GPIO chip functions potentially sleep. |
| */ |
| void gpiod_set_array(unsigned int array_size, |
| struct gpio_desc **desc_array, int *value_array) |
| { |
| if (!desc_array) |
| return; |
| gpiod_set_array_priv(false, false, array_size, desc_array, value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_array); |
| |
| /** |
| * gpiod_cansleep() - report whether gpio value access may sleep |
| * @desc: gpio to check |
| * |
| */ |
| int gpiod_cansleep(const struct gpio_desc *desc) |
| { |
| if (!desc) |
| return 0; |
| return desc->chip->can_sleep; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_cansleep); |
| |
| /** |
| * gpiod_to_irq() - return the IRQ corresponding to a GPIO |
| * @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. |
| */ |
| int gpiod_to_irq(const struct gpio_desc *desc) |
| { |
| struct gpio_chip *chip; |
| int offset; |
| |
| if (!desc) |
| return -EINVAL; |
| chip = desc->chip; |
| offset = gpio_chip_hwgpio(desc); |
| return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_to_irq); |
| |
| /** |
| * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ |
| * @chip: the chip the GPIO to lock belongs to |
| * @offset: the offset of the GPIO to lock as IRQ |
| * |
| * This is used directly by GPIO drivers that want to lock down |
| * a certain GPIO line to be used for IRQs. |
| */ |
| int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) |
| { |
| if (offset >= chip->ngpio) |
| return -EINVAL; |
| |
| if (test_bit(FLAG_IS_OUT, &chip->desc[offset].flags)) { |
| chip_err(chip, |
| "%s: tried to flag a GPIO set as output for IRQ\n", |
| __func__); |
| return -EIO; |
| } |
| |
| set_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); |
| |
| /** |
| * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ |
| * @chip: the chip the GPIO to lock belongs to |
| * @offset: the offset of the GPIO to lock as IRQ |
| * |
| * This is used directly by GPIO drivers that want to indicate |
| * that a certain GPIO is no longer used exclusively for IRQ. |
| */ |
| void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) |
| { |
| if (offset >= chip->ngpio) |
| return; |
| |
| clear_bit(FLAG_USED_AS_IRQ, &chip->desc[offset].flags); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); |
| |
| /** |
| * 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 |
| * its ACTIVE_LOW status. |
| * |
| * This function is to be called from contexts that can sleep. |
| */ |
| int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) |
| { |
| might_sleep_if(extra_checks); |
| if (!desc) |
| return 0; |
| return _gpiod_get_raw_value(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 |
| * |
| * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into |
| * account. |
| * |
| * This function is to be called from contexts that can sleep. |
| */ |
| int gpiod_get_value_cansleep(const struct gpio_desc *desc) |
| { |
| int value; |
| |
| might_sleep_if(extra_checks); |
| if (!desc) |
| return 0; |
| |
| value = _gpiod_get_raw_value(desc); |
| if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| value = !value; |
| |
| return value; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); |
| |
| /** |
| * 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 |
| * regard for its ACTIVE_LOW status. |
| * |
| * This function is to be called from contexts that can sleep. |
| */ |
| void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) |
| { |
| might_sleep_if(extra_checks); |
| if (!desc) |
| return; |
| _gpiod_set_raw_value(desc, 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 |
| * @value: value to assign |
| * |
| * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into |
| * account |
| * |
| * This function is to be called from contexts that can sleep. |
| */ |
| void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) |
| { |
| might_sleep_if(extra_checks); |
| if (!desc) |
| return; |
| |
| if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| value = !value; |
| _gpiod_set_raw_value(desc, value); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); |
| |
| /** |
| * gpiod_set_raw_array_cansleep() - assign values to an array of GPIOs |
| * @array_size: number of elements in the descriptor / value arrays |
| * @desc_array: array of GPIO descriptors whose values will be assigned |
| * @value_array: array of values to assign |
| * |
| * Set the raw values of the GPIOs, i.e. the values of the physical lines |
| * without regard for their ACTIVE_LOW status. |
| * |
| * This function is to be called from contexts that can sleep. |
| */ |
| void gpiod_set_raw_array_cansleep(unsigned int array_size, |
| struct gpio_desc **desc_array, |
| int *value_array) |
| { |
| might_sleep_if(extra_checks); |
| if (!desc_array) |
| return; |
| gpiod_set_array_priv(true, true, array_size, desc_array, value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_raw_array_cansleep); |
| |
| /** |
| * gpiod_set_array_cansleep() - assign values to an array of GPIOs |
| * @array_size: number of elements in the descriptor / value arrays |
| * @desc_array: array of GPIO descriptors whose values will be assigned |
| * @value_array: array of values to assign |
| * |
| * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status |
| * into account. |
| * |
| * This function is to be called from contexts that can sleep. |
| */ |
| void gpiod_set_array_cansleep(unsigned int array_size, |
| struct gpio_desc **desc_array, |
| int *value_array) |
| { |
| might_sleep_if(extra_checks); |
| if (!desc_array) |
| return; |
| gpiod_set_array_priv(false, true, array_size, desc_array, value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_array_cansleep); |
| |
| /** |
| * gpiod_add_lookup_table() - register GPIO device consumers |
| * @table: table of consumers to register |
| */ |
| void gpiod_add_lookup_table(struct gpiod_lookup_table *table) |
| { |
| mutex_lock(&gpio_lookup_lock); |
| |
| list_add_tail(&table->list, &gpio_lookup_list); |
| |
| mutex_unlock(&gpio_lookup_lock); |
| } |
| |
| static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id, |
| unsigned int idx, |
| enum gpio_lookup_flags *flags) |
| { |
| static const char *suffixes[] = { "gpios", "gpio" }; |
| char prop_name[32]; /* 32 is max size of property name */ |
| enum of_gpio_flags of_flags; |
| struct gpio_desc *desc; |
| unsigned int i; |
| |
| for (i = 0; i < ARRAY_SIZE(suffixes); i++) { |
| if (con_id) |
| snprintf(prop_name, 32, "%s-%s", con_id, suffixes[i]); |
| else |
| snprintf(prop_name, 32, "%s", suffixes[i]); |
| |
| desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx, |
| &of_flags); |
| if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) |
| break; |
| } |
| |
| if (IS_ERR(desc)) |
| return desc; |
| |
| if (of_flags & OF_GPIO_ACTIVE_LOW) |
| *flags |= GPIO_ACTIVE_LOW; |
| |
| return desc; |
| } |
| |
| static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
| unsigned int idx, |
| enum gpio_lookup_flags *flags) |
| { |
| static const char * const suffixes[] = { "gpios", "gpio" }; |
| struct acpi_device *adev = ACPI_COMPANION(dev); |
| struct acpi_gpio_info info; |
| struct gpio_desc *desc; |
| char propname[32]; |
| int i; |
| |
| /* Try first from _DSD */ |
| for (i = 0; i < ARRAY_SIZE(suffixes); i++) { |
| if (con_id && strcmp(con_id, "gpios")) { |
| snprintf(propname, sizeof(propname), "%s-%s", |
| con_id, suffixes[i]); |
| } else { |
| snprintf(propname, sizeof(propname), "%s", |
| suffixes[i]); |
| } |
| |
| desc = acpi_get_gpiod_by_index(adev, propname, idx, &info); |
| if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) |
| break; |
| } |
| |
| /* Then from plain _CRS GPIOs */ |
| if (IS_ERR(desc)) { |
| desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info); |
| if (IS_ERR(desc)) |
| return desc; |
| } |
| |
| if (info.active_low) |
| *flags |= GPIO_ACTIVE_LOW; |
| |
| return desc; |
| } |
| |
| static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) |
| { |
| const char *dev_id = dev ? dev_name(dev) : NULL; |
| struct gpiod_lookup_table *table; |
| |
| mutex_lock(&gpio_lookup_lock); |
| |
| list_for_each_entry(table, &gpio_lookup_list, list) { |
| if (table->dev_id && dev_id) { |
| /* |
| * Valid strings on both ends, must be identical to have |
| * a match |
| */ |
| if (!strcmp(table->dev_id, dev_id)) |
| goto found; |
| } else { |
| /* |
| * One of the pointers is NULL, so both must be to have |
| * a match |
| */ |
| if (dev_id == table->dev_id) |
| goto found; |
| } |
| } |
| table = NULL; |
| |
| found: |
| mutex_unlock(&gpio_lookup_lock); |
| return table; |
| } |
| |
| static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, |
| unsigned int idx, |
| enum gpio_lookup_flags *flags) |
| { |
| struct gpio_desc *desc = ERR_PTR(-ENOENT); |
| struct gpiod_lookup_table *table; |
| struct gpiod_lookup *p; |
| |
| table = gpiod_find_lookup_table(dev); |
| if (!table) |
| return desc; |
| |
| for (p = &table->table[0]; p->chip_label; p++) { |
| struct gpio_chip *chip; |
| |
| /* idx must always match exactly */ |
| if (p->idx != idx) |
| continue; |
| |
| /* If the lookup entry has a con_id, require exact match */ |
| if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) |
| continue; |
| |
| chip = find_chip_by_name(p->chip_label); |
| |
| if (!chip) { |
| dev_err(dev, "cannot find GPIO chip %s\n", |
| p->chip_label); |
| return ERR_PTR(-ENODEV); |
| } |
| |
| if (chip->ngpio <= p->chip_hwnum) { |
| dev_err(dev, |
| "requested GPIO %d is out of range [0..%d] for chip %s\n", |
| idx, chip->ngpio, chip->label); |
| return ERR_PTR(-EINVAL); |
| } |
| |
| desc = gpiochip_get_desc(chip, p->chip_hwnum); |
| *flags = p->flags; |
| |
| return desc; |
| } |
| |
| return desc; |
| } |
| |
| /** |
| * gpiod_get - obtain a GPIO for a given GPIO function |
| * @dev: GPIO consumer, can be NULL for system-global GPIOs |
| * @con_id: function within the GPIO consumer |
| * @flags: optional GPIO initialization flags |
| * |
| * Return 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 occured while trying to acquire the GPIO. |
| */ |
| struct gpio_desc *__must_check __gpiod_get(struct device *dev, const char *con_id, |
| enum gpiod_flags flags) |
| { |
| return gpiod_get_index(dev, con_id, 0, flags); |
| } |
| EXPORT_SYMBOL_GPL(__gpiod_get); |
| |
| /** |
| * gpiod_get_optional - obtain an optional GPIO for a given GPIO function |
| * @dev: GPIO consumer, can be NULL for system-global GPIOs |
| * @con_id: function within the GPIO consumer |
| * @flags: optional GPIO initialization flags |
| * |
| * 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. |
| */ |
| struct gpio_desc *__must_check __gpiod_get_optional(struct device *dev, |
| const char *con_id, |
| enum gpiod_flags flags) |
| { |
| return gpiod_get_index_optional(dev, con_id, 0, flags); |
| } |
| EXPORT_SYMBOL_GPL(__gpiod_get_optional); |
| |
| /** |
| * gpiod_get_index - obtain a GPIO from a multi-index GPIO function |
| * @dev: GPIO consumer, can be NULL for system-global GPIOs |
| * @con_id: function within the GPIO consumer |
| * @idx: index of the GPIO to obtain in the consumer |
| * @flags: optional GPIO initialization flags |
| * |
| * 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 |
| * requested function and/or index, or another IS_ERR() code if an error |
| * occured while trying to acquire the GPIO. |
| */ |
| struct gpio_desc *__must_check __gpiod_get_index(struct device *dev, |
| const char *con_id, |
| unsigned int idx, |
| enum gpiod_flags flags) |
| { |
| struct gpio_desc *desc = NULL; |
| int status; |
| enum gpio_lookup_flags lookupflags = 0; |
| |
| dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); |
| |
| /* Using device tree? */ |
| if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) { |
| dev_dbg(dev, "using device tree for GPIO lookup\n"); |
| desc = of_find_gpio(dev, con_id, idx, &lookupflags); |
| } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) { |
| dev_dbg(dev, "using ACPI for GPIO lookup\n"); |
| desc = acpi_find_gpio(dev, con_id, idx, &lookupflags); |
| } |
| |
| /* |
| * Either we are not using DT or ACPI, or their lookup did not return |
| * a result. In that case, use platform lookup as a fallback. |
| */ |
| if (!desc || desc == ERR_PTR(-ENOENT)) { |
| dev_dbg(dev, "using lookup tables for GPIO lookup\n"); |
| desc = gpiod_find(dev, con_id, idx, &lookupflags); |
| } |
| |
| if (IS_ERR(desc)) { |
| dev_dbg(dev, "lookup for GPIO %s failed\n", con_id); |
| return desc; |
| } |
| |
| status = gpiod_request(desc, con_id); |
| |
| if (status < 0) |
| return ERR_PTR(status); |
| |
| if (lookupflags & GPIO_ACTIVE_LOW) |
| set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| if (lookupflags & GPIO_OPEN_DRAIN) |
| set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
| if (lookupflags & GPIO_OPEN_SOURCE) |
| set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
| |
| /* No particular flag request, return here... */ |
| if (!(flags & GPIOD_FLAGS_BIT_DIR_SET)) |
| return desc; |
| |
| /* Process flags */ |
| if (flags & GPIOD_FLAGS_BIT_DIR_OUT) |
| status = gpiod_direction_output(desc, |
| flags & GPIOD_FLAGS_BIT_DIR_VAL); |
| else |
| status = gpiod_direction_input(desc); |
| |
| if (status < 0) { |
| dev_dbg(dev, "setup of GPIO %s failed\n", con_id); |
| gpiod_put(desc); |
| return ERR_PTR(status); |
| } |
| |
| return desc; |
| } |
| EXPORT_SYMBOL_GPL(__gpiod_get_index); |
| |
| /** |
| * fwnode_get_named_gpiod - obtain a GPIO from firmware node |
| * @fwnode: handle of the firmware node |
| * @propname: name of the firmware property representing the GPIO |
| * |
| * This function can be used for drivers that get their configuration |
| * from firmware. |
| * |
| * Function properly finds the corresponding GPIO using whatever is the |
| * underlying firmware interface and then makes sure that the GPIO |
| * descriptor is requested before it is returned to the caller. |
| * |
| * In case of error an ERR_PTR() is returned. |
| */ |
| struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, |
| const char *propname) |
| { |
| struct gpio_desc *desc = ERR_PTR(-ENODEV); |
| bool active_low = false; |
| int ret; |
| |
| if (!fwnode) |
| return ERR_PTR(-EINVAL); |
| |
| if (is_of_node(fwnode)) { |
| enum of_gpio_flags flags; |
| |
| desc = of_get_named_gpiod_flags(of_node(fwnode), propname, 0, |
| &flags); |
| if (!IS_ERR(desc)) |
| active_low = flags & OF_GPIO_ACTIVE_LOW; |
| } else if (is_acpi_node(fwnode)) { |
| struct acpi_gpio_info info; |
| |
| desc = acpi_get_gpiod_by_index(acpi_node(fwnode), propname, 0, |
| &info); |
| if (!IS_ERR(desc)) |
| active_low = info.active_low; |
| } |
| |
| if (IS_ERR(desc)) |
| return desc; |
| |
| ret = gpiod_request(desc, NULL); |
| if (ret) |
| return ERR_PTR(ret); |
| |
| /* Only value flag can be set from both DT and ACPI is active_low */ |
| if (active_low) |
| set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| |
| return desc; |
| } |
| EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); |
| |
| /** |
| * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO |
| * function |
| * @dev: GPIO consumer, can be NULL for system-global GPIOs |
| * @con_id: function within the GPIO consumer |
| * @index: index of the GPIO to obtain in the consumer |
| * @flags: optional GPIO initialization flags |
| * |
| * 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. |
| */ |
| struct gpio_desc *__must_check __gpiod_get_index_optional(struct device *dev, |
| const char *con_id, |
| unsigned int index, |
| enum gpiod_flags flags) |
| { |
| struct gpio_desc *desc; |
| |
| desc = gpiod_get_index(dev, con_id, index, flags); |
| if (IS_ERR(desc)) { |
| if (PTR_ERR(desc) == -ENOENT) |
| return NULL; |
| } |
| |
| return desc; |
| } |
| EXPORT_SYMBOL_GPL(__gpiod_get_index_optional); |
| |
| /** |
| * gpiod_put - dispose of a GPIO descriptor |
| * @desc: GPIO descriptor to dispose of |
| * |
| * No descriptor can be used after gpiod_put() has been called on it. |
| */ |
| void gpiod_put(struct gpio_desc *desc) |
| { |
| gpiod_free(desc); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_put); |
| |
| #ifdef CONFIG_DEBUG_FS |
| |
| static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) |
| { |
| unsigned i; |
| unsigned gpio = chip->base; |
| struct gpio_desc *gdesc = &chip->desc[0]; |
| int is_out; |
| int is_irq; |
| |
| for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { |
| if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) |
| continue; |
| |
| gpiod_get_direction(gdesc); |
| is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); |
| is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); |
| seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s", |
| gpio, gdesc->label, |
| is_out ? "out" : "in ", |
| chip->get |
| ? (chip->get(chip, i) ? "hi" : "lo") |
| : "? ", |
| is_irq ? "IRQ" : " "); |
| seq_printf(s, "\n"); |
| } |
| } |
| |
| static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) |
| { |
| unsigned long flags; |
| struct gpio_chip *chip = NULL; |
| loff_t index = *pos; |
| |
| s->private = ""; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| list_for_each_entry(chip, &gpio_chips, list) |
| if (index-- == 0) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return chip; |
| } |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| return NULL; |
| } |
| |
| static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| { |
| unsigned long flags; |
| struct gpio_chip *chip = v; |
| void *ret = NULL; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| if (list_is_last(&chip->list, &gpio_chips)) |
| ret = NULL; |
| else |
| ret = list_entry(chip->list.next, struct gpio_chip, list); |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| s->private = "\n"; |
| ++*pos; |
| |
| return ret; |
| } |
| |
| static void gpiolib_seq_stop(struct seq_file *s, void *v) |
| { |
| } |
| |
| static int gpiolib_seq_show(struct seq_file *s, void *v) |
| { |
| struct gpio_chip *chip = v; |
| struct device *dev; |
| |
| seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, |
| chip->base, chip->base + chip->ngpio - 1); |
| dev = chip->dev; |
| if (dev) |
| seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", |
| dev_name(dev)); |
| if (chip->label) |
| seq_printf(s, ", %s", chip->label); |
| if (chip->can_sleep) |
| seq_printf(s, ", can sleep"); |
| seq_printf(s, ":\n"); |
| |
| if (chip->dbg_show) |
| chip->dbg_show(s, chip); |
| else |
| gpiolib_dbg_show(s, chip); |
| |
| return 0; |
| } |
| |
| static const struct seq_operations gpiolib_seq_ops = { |
| .start = gpiolib_seq_start, |
| .next = gpiolib_seq_next, |
| .stop = gpiolib_seq_stop, |
| .show = gpiolib_seq_show, |
| }; |
| |
| static int gpiolib_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &gpiolib_seq_ops); |
| } |
| |
| static const struct file_operations gpiolib_operations = { |
| .owner = THIS_MODULE, |
| .open = gpiolib_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| static int __init gpiolib_debugfs_init(void) |
| { |
| /* /sys/kernel/debug/gpio */ |
| (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, |
| NULL, NULL, &gpiolib_operations); |
| return 0; |
| } |
| subsys_initcall(gpiolib_debugfs_init); |
| |
| #endif /* DEBUG_FS */ |