| #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 <linux/pinctrl/consumer.h> |
| #include <linux/idr.h> |
| #include <linux/cdev.h> |
| #include <linux/fs.h> |
| #include <linux/uaccess.h> |
| #include <uapi/linux/gpio.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 |
| |
| /* Device and char device-related information */ |
| static DEFINE_IDA(gpio_ida); |
| static dev_t gpio_devt; |
| #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */ |
| static struct bus_type gpio_bus_type = { |
| .name = "gpio", |
| }; |
| |
| /* 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); |
| |
| static DEFINE_MUTEX(gpio_lookup_lock); |
| static LIST_HEAD(gpio_lookup_list); |
| LIST_HEAD(gpio_devices); |
| |
| static void gpiochip_free_hogs(struct gpio_chip *chip); |
| static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); |
| |
| |
| 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_device *gdev; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| list_for_each_entry(gdev, &gpio_devices, list) { |
| if (gdev->base <= gpio && |
| gdev->base + gdev->ngpio > gpio) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return &gdev->descs[gpio - gdev->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) |
| { |
| struct gpio_device *gdev = chip->gpiodev; |
| |
| if (hwnum >= gdev->ngpio) |
| return ERR_PTR(-EINVAL); |
| |
| return &gdev->descs[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->gdev->base + (desc - &desc->gdev->descs[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) |
| { |
| if (!desc || !desc->gdev || !desc->gdev->chip) |
| return NULL; |
| return desc->gdev->chip; |
| } |
| 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_device *gdev; |
| int base = ARCH_NR_GPIOS - ngpio; |
| |
| list_for_each_entry_reverse(gdev, &gpio_devices, list) { |
| /* found a free space? */ |
| if (gdev->base + gdev->ngpio <= base) |
| break; |
| else |
| /* nope, check the space right before the chip */ |
| base = gdev->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 range(means [base, base + ngpio - 1]) order. |
| * |
| * Return -EBUSY if the new chip overlaps with some other chip's integer |
| * space. |
| */ |
| static int gpiodev_add_to_list(struct gpio_device *gdev) |
| { |
| struct gpio_device *prev, *next; |
| |
| if (list_empty(&gpio_devices)) { |
| /* initial entry in list */ |
| list_add_tail(&gdev->list, &gpio_devices); |
| return 0; |
| } |
| |
| next = list_entry(gpio_devices.next, struct gpio_device, list); |
| if (gdev->base + gdev->ngpio <= next->base) { |
| /* add before first entry */ |
| list_add(&gdev->list, &gpio_devices); |
| return 0; |
| } |
| |
| prev = list_entry(gpio_devices.prev, struct gpio_device, list); |
| if (prev->base + prev->ngpio <= gdev->base) { |
| /* add behind last entry */ |
| list_add_tail(&gdev->list, &gpio_devices); |
| return 0; |
| } |
| |
| list_for_each_entry_safe(prev, next, &gpio_devices, list) { |
| /* at the end of the list */ |
| if (&next->list == &gpio_devices) |
| break; |
| |
| /* add between prev and next */ |
| if (prev->base + prev->ngpio <= gdev->base |
| && gdev->base + gdev->ngpio <= next->base) { |
| list_add(&gdev->list, &prev->list); |
| return 0; |
| } |
| } |
| |
| dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n"); |
| return -EBUSY; |
| } |
| |
| /** |
| * Convert a GPIO name to its descriptor |
| */ |
| static struct gpio_desc *gpio_name_to_desc(const char * const name) |
| { |
| struct gpio_device *gdev; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| list_for_each_entry(gdev, &gpio_devices, list) { |
| int i; |
| |
| for (i = 0; i != gdev->ngpio; ++i) { |
| struct gpio_desc *desc = &gdev->descs[i]; |
| |
| if (!desc->name || !name) |
| continue; |
| |
| if (!strcmp(desc->name, name)) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return desc; |
| } |
| } |
| } |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| return NULL; |
| } |
| |
| /* |
| * Takes the names from gc->names and checks if they are all unique. If they |
| * are, they are assigned to their gpio descriptors. |
| * |
| * Warning if one of the names is already used for a different GPIO. |
| */ |
| static int gpiochip_set_desc_names(struct gpio_chip *gc) |
| { |
| struct gpio_device *gdev = gc->gpiodev; |
| int i; |
| |
| if (!gc->names) |
| return 0; |
| |
| /* First check all names if they are unique */ |
| for (i = 0; i != gc->ngpio; ++i) { |
| struct gpio_desc *gpio; |
| |
| gpio = gpio_name_to_desc(gc->names[i]); |
| if (gpio) |
| dev_warn(&gdev->dev, |
| "Detected name collision for GPIO name '%s'\n", |
| gc->names[i]); |
| } |
| |
| /* Then add all names to the GPIO descriptors */ |
| for (i = 0; i != gc->ngpio; ++i) |
| gdev->descs[i].name = gc->names[i]; |
| |
| return 0; |
| } |
| |
| /** |
| * gpio_ioctl() - ioctl handler for the GPIO chardev |
| */ |
| static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) |
| { |
| struct gpio_device *gdev = filp->private_data; |
| struct gpio_chip *chip = gdev->chip; |
| int __user *ip = (int __user *)arg; |
| |
| /* We fail any subsequent ioctl():s when the chip is gone */ |
| if (!chip) |
| return -ENODEV; |
| |
| /* Fill in the struct and pass to userspace */ |
| if (cmd == GPIO_GET_CHIPINFO_IOCTL) { |
| struct gpiochip_info chipinfo; |
| |
| strncpy(chipinfo.name, dev_name(&gdev->dev), |
| sizeof(chipinfo.name)); |
| chipinfo.name[sizeof(chipinfo.name)-1] = '\0'; |
| strncpy(chipinfo.label, gdev->label, |
| sizeof(chipinfo.label)); |
| chipinfo.label[sizeof(chipinfo.label)-1] = '\0'; |
| chipinfo.lines = gdev->ngpio; |
| if (copy_to_user(ip, &chipinfo, sizeof(chipinfo))) |
| return -EFAULT; |
| return 0; |
| } else if (cmd == GPIO_GET_LINEINFO_IOCTL) { |
| struct gpioline_info lineinfo; |
| struct gpio_desc *desc; |
| |
| if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) |
| return -EFAULT; |
| if (lineinfo.line_offset > gdev->ngpio) |
| return -EINVAL; |
| |
| desc = &gdev->descs[lineinfo.line_offset]; |
| if (desc->name) { |
| strncpy(lineinfo.name, desc->name, |
| sizeof(lineinfo.name)); |
| lineinfo.name[sizeof(lineinfo.name)-1] = '\0'; |
| } else { |
| lineinfo.name[0] = '\0'; |
| } |
| if (desc->label) { |
| strncpy(lineinfo.consumer, desc->label, |
| sizeof(lineinfo.consumer)); |
| lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0'; |
| } else { |
| lineinfo.consumer[0] = '\0'; |
| } |
| |
| /* |
| * Userspace only need to know that the kernel is using |
| * this GPIO so it can't use it. |
| */ |
| lineinfo.flags = 0; |
| if (test_bit(FLAG_REQUESTED, &desc->flags) || |
| test_bit(FLAG_IS_HOGGED, &desc->flags) || |
| test_bit(FLAG_USED_AS_IRQ, &desc->flags) || |
| test_bit(FLAG_EXPORT, &desc->flags) || |
| test_bit(FLAG_SYSFS, &desc->flags)) |
| lineinfo.flags |= GPIOLINE_FLAG_KERNEL; |
| if (test_bit(FLAG_IS_OUT, &desc->flags)) |
| lineinfo.flags |= GPIOLINE_FLAG_IS_OUT; |
| if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) |
| lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW; |
| if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) |
| lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN; |
| if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) |
| lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE; |
| |
| if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) |
| return -EFAULT; |
| return 0; |
| } |
| return -EINVAL; |
| } |
| |
| /** |
| * gpio_chrdev_open() - open the chardev for ioctl operations |
| * @inode: inode for this chardev |
| * @filp: file struct for storing private data |
| * Returns 0 on success |
| */ |
| static int gpio_chrdev_open(struct inode *inode, struct file *filp) |
| { |
| struct gpio_device *gdev = container_of(inode->i_cdev, |
| struct gpio_device, chrdev); |
| |
| /* Fail on open if the backing gpiochip is gone */ |
| if (!gdev || !gdev->chip) |
| return -ENODEV; |
| get_device(&gdev->dev); |
| filp->private_data = gdev; |
| return 0; |
| } |
| |
| /** |
| * gpio_chrdev_release() - close chardev after ioctl operations |
| * @inode: inode for this chardev |
| * @filp: file struct for storing private data |
| * Returns 0 on success |
| */ |
| static int gpio_chrdev_release(struct inode *inode, struct file *filp) |
| { |
| struct gpio_device *gdev = container_of(inode->i_cdev, |
| struct gpio_device, chrdev); |
| |
| if (!gdev) |
| return -ENODEV; |
| put_device(&gdev->dev); |
| return 0; |
| } |
| |
| |
| static const struct file_operations gpio_fileops = { |
| .release = gpio_chrdev_release, |
| .open = gpio_chrdev_open, |
| .owner = THIS_MODULE, |
| .llseek = noop_llseek, |
| .unlocked_ioctl = gpio_ioctl, |
| .compat_ioctl = gpio_ioctl, |
| }; |
| |
| static void gpiodevice_release(struct device *dev) |
| { |
| struct gpio_device *gdev = dev_get_drvdata(dev); |
| |
| cdev_del(&gdev->chrdev); |
| list_del(&gdev->list); |
| ida_simple_remove(&gpio_ida, gdev->id); |
| kfree(gdev); |
| } |
| |
| /** |
| * gpiochip_add_data() - 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_data() is called very early during boot, so that GPIOs |
| * can be freely used, the chip->parent 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_data(struct gpio_chip *chip, void *data) |
| { |
| unsigned long flags; |
| int status = 0; |
| unsigned i; |
| int base = chip->base; |
| struct gpio_device *gdev; |
| |
| /* |
| * First: allocate and populate the internal stat container, and |
| * set up the struct device. |
| */ |
| gdev = kzalloc(sizeof(*gdev), GFP_KERNEL); |
| if (!gdev) |
| return -ENOMEM; |
| gdev->dev.bus = &gpio_bus_type; |
| gdev->chip = chip; |
| chip->gpiodev = gdev; |
| if (chip->parent) { |
| gdev->dev.parent = chip->parent; |
| gdev->dev.of_node = chip->parent->of_node; |
| } else { |
| #ifdef CONFIG_OF_GPIO |
| /* If the gpiochip has an assigned OF node this takes precedence */ |
| if (chip->of_node) |
| gdev->dev.of_node = chip->of_node; |
| #endif |
| } |
| gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL); |
| if (gdev->id < 0) { |
| status = gdev->id; |
| goto err_free_gdev; |
| } |
| dev_set_name(&gdev->dev, "gpiochip%d", gdev->id); |
| device_initialize(&gdev->dev); |
| dev_set_drvdata(&gdev->dev, gdev); |
| if (chip->parent && chip->parent->driver) |
| gdev->owner = chip->parent->driver->owner; |
| else if (chip->owner) |
| /* TODO: remove chip->owner */ |
| gdev->owner = chip->owner; |
| else |
| gdev->owner = THIS_MODULE; |
| |
| gdev->descs = devm_kcalloc(&gdev->dev, chip->ngpio, |
| sizeof(gdev->descs[0]), GFP_KERNEL); |
| if (!gdev->descs) { |
| status = -ENOMEM; |
| goto err_free_gdev; |
| } |
| |
| if (chip->ngpio == 0) { |
| chip_err(chip, "tried to insert a GPIO chip with zero lines\n"); |
| status = -EINVAL; |
| goto err_free_gdev; |
| } |
| |
| if (chip->label) |
| gdev->label = devm_kstrdup(&gdev->dev, chip->label, GFP_KERNEL); |
| else |
| gdev->label = devm_kstrdup(&gdev->dev, "unknown", GFP_KERNEL); |
| if (!gdev->label) { |
| status = -ENOMEM; |
| goto err_free_gdev; |
| } |
| |
| gdev->ngpio = chip->ngpio; |
| gdev->data = data; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| |
| /* |
| * TODO: this allocates a Linux GPIO number base in the global |
| * GPIO numberspace for this chip. In the long run we want to |
| * get *rid* of this numberspace and use only descriptors, but |
| * it may be a pipe dream. It will not happen before we get rid |
| * of the sysfs interface anyways. |
| */ |
| if (base < 0) { |
| base = gpiochip_find_base(chip->ngpio); |
| if (base < 0) { |
| status = base; |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| goto err_free_gdev; |
| } |
| /* |
| * TODO: it should not be necessary to reflect the assigned |
| * base outside of the GPIO subsystem. Go over drivers and |
| * see if anyone makes use of this, else drop this and assign |
| * a poison instead. |
| */ |
| chip->base = base; |
| } |
| gdev->base = base; |
| |
| status = gpiodev_add_to_list(gdev); |
| if (status) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| goto err_free_gdev; |
| } |
| |
| for (i = 0; i < chip->ngpio; i++) { |
| struct gpio_desc *desc = &gdev->descs[i]; |
| |
| desc->gdev = gdev; |
| |
| /* 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; |
| } |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| #ifdef CONFIG_PINCTRL |
| INIT_LIST_HEAD(&gdev->pin_ranges); |
| #endif |
| |
| status = gpiochip_set_desc_names(chip); |
| if (status) |
| goto err_remove_from_list; |
| |
| status = of_gpiochip_add(chip); |
| if (status) |
| goto err_remove_chip; |
| |
| acpi_gpiochip_add(chip); |
| |
| /* |
| * By first adding the chardev, and then adding the device, |
| * we get a device node entry in sysfs under |
| * /sys/bus/gpio/devices/gpiochipN/dev that can be used for |
| * coldplug of device nodes and other udev business. |
| */ |
| cdev_init(&gdev->chrdev, &gpio_fileops); |
| gdev->chrdev.owner = THIS_MODULE; |
| gdev->chrdev.kobj.parent = &gdev->dev.kobj; |
| gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id); |
| status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1); |
| if (status < 0) |
| chip_warn(chip, "failed to add char device %d:%d\n", |
| MAJOR(gpio_devt), gdev->id); |
| else |
| chip_dbg(chip, "added GPIO chardev (%d:%d)\n", |
| MAJOR(gpio_devt), gdev->id); |
| status = device_add(&gdev->dev); |
| if (status) |
| goto err_remove_chardev; |
| |
| status = gpiochip_sysfs_register(gdev); |
| if (status) |
| goto err_remove_device; |
| |
| /* From this point, the .release() function cleans up gpio_device */ |
| gdev->dev.release = gpiodevice_release; |
| get_device(&gdev->dev); |
| pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n", |
| __func__, gdev->base, gdev->base + gdev->ngpio - 1, |
| dev_name(&gdev->dev), chip->label ? : "generic"); |
| |
| return 0; |
| |
| err_remove_device: |
| device_del(&gdev->dev); |
| err_remove_chardev: |
| cdev_del(&gdev->chrdev); |
| err_remove_chip: |
| acpi_gpiochip_remove(chip); |
| gpiochip_free_hogs(chip); |
| of_gpiochip_remove(chip); |
| err_remove_from_list: |
| spin_lock_irqsave(&gpio_lock, flags); |
| list_del(&gdev->list); |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| err_free_gdev: |
| ida_simple_remove(&gpio_ida, gdev->id); |
| /* failures here can mean systems won't boot... */ |
| pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__, |
| gdev->base, gdev->base + gdev->ngpio - 1, |
| chip->label ? : "generic"); |
| kfree(gdev); |
| return status; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_add_data); |
| |
| /** |
| * gpiochip_get_data() - get per-subdriver data for the chip |
| */ |
| void *gpiochip_get_data(struct gpio_chip *chip) |
| { |
| return chip->gpiodev->data; |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_get_data); |
| |
| /** |
| * 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) |
| { |
| struct gpio_device *gdev = chip->gpiodev; |
| struct gpio_desc *desc; |
| unsigned long flags; |
| unsigned i; |
| bool requested = false; |
| |
| /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ |
| gpiochip_sysfs_unregister(gdev); |
| /* Numb the device, cancelling all outstanding operations */ |
| gdev->chip = NULL; |
| gpiochip_irqchip_remove(chip); |
| acpi_gpiochip_remove(chip); |
| gpiochip_remove_pin_ranges(chip); |
| gpiochip_free_hogs(chip); |
| of_gpiochip_remove(chip); |
| /* |
| * We accept no more calls into the driver from this point, so |
| * NULL the driver data pointer |
| */ |
| gdev->data = NULL; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| for (i = 0; i < gdev->ngpio; i++) { |
| desc = &gdev->descs[i]; |
| if (test_bit(FLAG_REQUESTED, &desc->flags)) |
| requested = true; |
| } |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| |
| if (requested) |
| dev_crit(&gdev->dev, |
| "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); |
| |
| /* |
| * The gpiochip 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. |
| */ |
| put_device(&gdev->dev); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_remove); |
| |
| static void devm_gpio_chip_release(struct device *dev, void *res) |
| { |
| struct gpio_chip *chip = *(struct gpio_chip **)res; |
| |
| gpiochip_remove(chip); |
| } |
| |
| static int devm_gpio_chip_match(struct device *dev, void *res, void *data) |
| |
| { |
| struct gpio_chip **r = res; |
| |
| if (!r || !*r) { |
| WARN_ON(!r || !*r); |
| return 0; |
| } |
| |
| return *r == data; |
| } |
| |
| /** |
| * devm_gpiochip_add_data() - Resource manager piochip_add_data() |
| * @dev: the device pointer on which irq_chip belongs to. |
| * @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. |
| * |
| * The gpio chip automatically be released when the device is unbound. |
| */ |
| int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip, |
| void *data) |
| { |
| struct gpio_chip **ptr; |
| int ret; |
| |
| ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr), |
| GFP_KERNEL); |
| if (!ptr) |
| return -ENOMEM; |
| |
| ret = gpiochip_add_data(chip, data); |
| if (ret < 0) { |
| devres_free(ptr); |
| return ret; |
| } |
| |
| *ptr = chip; |
| devres_add(dev, ptr); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(devm_gpiochip_add_data); |
| |
| /** |
| * devm_gpiochip_remove() - Resource manager of gpiochip_remove() |
| * @dev: device for which which resource was allocated |
| * @chip: the chip to remove |
| * |
| * A gpio_chip with any GPIOs still requested may not be removed. |
| */ |
| void devm_gpiochip_remove(struct device *dev, struct gpio_chip *chip) |
| { |
| int ret; |
| |
| ret = devres_release(dev, devm_gpio_chip_release, |
| devm_gpio_chip_match, chip); |
| if (!ret) |
| WARN_ON(ret); |
| } |
| EXPORT_SYMBOL_GPL(devm_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_device *gdev; |
| struct gpio_chip *chip; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| list_for_each_entry(gdev, &gpio_devices, list) |
| if (match(gdev->chip, data)) |
| break; |
| |
| /* No match? */ |
| if (&gdev->list == &gpio_devices) |
| chip = NULL; |
| else |
| chip = gdev->chip; |
| |
| 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_chained_handler_and_data(parent_irq, parent_handler, |
| gpiochip); |
| |
| gpiochip->irq_parent = parent_irq; |
| } |
| |
| /* 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); |
| |
| /** |
| * 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); |
| /* |
| * 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, chip->lock_key); |
| 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); |
| irq_set_noprobe(irq); |
| |
| /* |
| * 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; |
| |
| 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 (!try_module_get(chip->gpiodev->owner)) |
| return -ENODEV; |
| |
| if (gpiochip_lock_as_irq(chip, d->hwirq)) { |
| chip_err(chip, |
| "unable to lock HW IRQ %lu for IRQ\n", |
| d->hwirq); |
| module_put(chip->gpiodev->owner); |
| 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); |
| module_put(chip->gpiodev->owner); |
| } |
| |
| 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); |
| |
| if (gpiochip->irq_parent) { |
| irq_set_chained_handler(gpiochip->irq_parent, NULL); |
| irq_set_handler_data(gpiochip->irq_parent, NULL); |
| } |
| |
| /* 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. |
| * @lock_key: lockdep class |
| * |
| * 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 gpiochip_get_data() 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 lock_class_key *lock_key) |
| { |
| struct device_node *of_node; |
| unsigned int offset; |
| unsigned irq_base = 0; |
| |
| if (!gpiochip || !irqchip) |
| return -EINVAL; |
| |
| if (!gpiochip->parent) { |
| pr_err("missing gpiochip .dev parent pointer\n"); |
| return -EINVAL; |
| } |
| of_node = gpiochip->parent->of_node; |
| #ifdef CONFIG_OF_GPIO |
| /* |
| * If the gpiochip has an assigned OF node this takes precedence |
| * FIXME: get rid of this and use gpiochip->parent->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->lock_key = lock_key; |
| gpiochip->irqdomain = irq_domain_add_simple(of_node, |
| gpiochip->ngpio, first_irq, |
| &gpiochip_domain_ops, gpiochip); |
| if (!gpiochip->irqdomain) { |
| gpiochip->irqchip = NULL; |
| return -EINVAL; |
| } |
| |
| /* |
| * It is possible for a driver to override this, but only if the |
| * alternative functions are both implemented. |
| */ |
| if (!irqchip->irq_request_resources && |
| !irqchip->irq_release_resources) { |
| 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 */ |
| |
| /** |
| * gpiochip_generic_request() - request the gpio function for a pin |
| * @chip: the gpiochip owning the GPIO |
| * @offset: the offset of the GPIO to request for GPIO function |
| */ |
| int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset) |
| { |
| return pinctrl_request_gpio(chip->gpiodev->base + offset); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_generic_request); |
| |
| /** |
| * gpiochip_generic_free() - free the gpio function from a pin |
| * @chip: the gpiochip to request the gpio function for |
| * @offset: the offset of the GPIO to free from GPIO function |
| */ |
| void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset) |
| { |
| pinctrl_free_gpio(chip->gpiodev->base + offset); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_generic_free); |
| |
| #ifdef CONFIG_PINCTRL |
| |
| /** |
| * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping |
| * @chip: the gpiochip to add the range for |
| * @pctldev: 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; |
| struct gpio_device *gdev = chip->gpiodev; |
| 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 = gdev->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, &gdev->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; |
| struct gpio_device *gdev = chip->gpiodev; |
| 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 = gdev->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, &gdev->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; |
| struct gpio_device *gdev = chip->gpiodev; |
| |
| list_for_each_entry_safe(pin_range, tmp, &gdev->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->gdev->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: |
| if (status < 0) { |
| /* Clear flags that might have been set by the caller before |
| * requesting the GPIO. |
| */ |
| clear_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| clear_bit(FLAG_OPEN_DRAIN, &desc->flags); |
| clear_bit(FLAG_OPEN_SOURCE, &desc->flags); |
| } |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return status; |
| } |
| |
| /* |
| * This descriptor validation needs to be inserted verbatim into each |
| * function taking a descriptor, so we need to use a preprocessor |
| * macro to avoid endless duplication. |
| */ |
| #define VALIDATE_DESC(desc) do { \ |
| if (!desc || !desc->gdev) { \ |
| pr_warn("%s: invalid GPIO\n", __func__); \ |
| return -EINVAL; \ |
| } \ |
| if ( !desc->gdev->chip ) { \ |
| dev_warn(&desc->gdev->dev, \ |
| "%s: backing chip is gone\n", __func__); \ |
| return 0; \ |
| } } while (0) |
| |
| #define VALIDATE_DESC_VOID(desc) do { \ |
| if (!desc || !desc->gdev) { \ |
| pr_warn("%s: invalid GPIO\n", __func__); \ |
| return; \ |
| } \ |
| if (!desc->gdev->chip) { \ |
| dev_warn(&desc->gdev->dev, \ |
| "%s: backing chip is gone\n", __func__); \ |
| return; \ |
| } } while (0) |
| |
| |
| int gpiod_request(struct gpio_desc *desc, const char *label) |
| { |
| int status = -EPROBE_DEFER; |
| struct gpio_device *gdev; |
| |
| VALIDATE_DESC(desc); |
| gdev = desc->gdev; |
| |
| if (try_module_get(gdev->owner)) { |
| status = __gpiod_request(desc, label); |
| if (status < 0) |
| module_put(gdev->owner); |
| else |
| get_device(&gdev->dev); |
| } |
| |
| 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->gdev->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); |
| clear_bit(FLAG_IS_HOGGED, &desc->flags); |
| ret = true; |
| } |
| |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return ret; |
| } |
| |
| void gpiod_free(struct gpio_desc *desc) |
| { |
| if (desc && desc->gdev && __gpiod_free(desc)) { |
| module_put(desc->gdev->owner); |
| put_device(&desc->gdev->dev); |
| } 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 (offset >= chip->ngpio) |
| return NULL; |
| |
| desc = &chip->gpiodev->descs[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; |
| |
| VALIDATE_DESC(desc); |
| chip = desc->gdev->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->gdev->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) |
| { |
| VALIDATE_DESC(desc); |
| 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) |
| { |
| VALIDATE_DESC(desc); |
| 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; |
| |
| VALIDATE_DESC(desc); |
| chip = desc->gdev->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) |
| { |
| VALIDATE_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 int _gpiod_get_raw_value(const struct gpio_desc *desc) |
| { |
| struct gpio_chip *chip; |
| int offset; |
| int value; |
| |
| chip = desc->gdev->chip; |
| offset = gpio_chip_hwgpio(desc); |
| value = chip->get ? chip->get(chip, offset) : -EIO; |
| value = value < 0 ? value : !!value; |
| 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, or negative errno on failure. |
| * |
| * 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) |
| { |
| VALIDATE_DESC(desc); |
| /* Should be using gpio_get_value_cansleep() */ |
| WARN_ON(desc->gdev->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, or negative errno on failure. |
| * |
| * 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; |
| |
| VALIDATE_DESC(desc); |
| /* Should be using gpio_get_value_cansleep() */ |
| WARN_ON(desc->gdev->chip->can_sleep); |
| |
| value = _gpiod_get_raw_value(desc); |
| if (value < 0) |
| return value; |
| |
| 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 otherwise 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->gdev->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 otherwise 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->gdev->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->gdev->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_value_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]->gdev->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]->gdev->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) |
| { |
| VALIDATE_DESC_VOID(desc); |
| /* Should be using gpiod_set_value_cansleep() */ |
| WARN_ON(desc->gdev->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) |
| { |
| VALIDATE_DESC_VOID(desc); |
| /* Should be using gpiod_set_value_cansleep() */ |
| WARN_ON(desc->gdev->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_value() - 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_value(unsigned int array_size, |
| struct gpio_desc **desc_array, int *value_array) |
| { |
| if (!desc_array) |
| return; |
| gpiod_set_array_value_priv(true, false, array_size, desc_array, |
| value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); |
| |
| /** |
| * gpiod_set_array_value() - 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_value(unsigned int array_size, |
| struct gpio_desc **desc_array, int *value_array) |
| { |
| if (!desc_array) |
| return; |
| gpiod_set_array_value_priv(false, false, array_size, desc_array, |
| value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_array_value); |
| |
| /** |
| * gpiod_cansleep() - report whether gpio value access may sleep |
| * @desc: gpio to check |
| * |
| */ |
| int gpiod_cansleep(const struct gpio_desc *desc) |
| { |
| VALIDATE_DESC(desc); |
| return desc->gdev->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; |
| |
| VALIDATE_DESC(desc); |
| chip = desc->gdev->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->gpiodev->descs[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->gpiodev->descs[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->gpiodev->descs[offset].flags); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); |
| |
| bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset) |
| { |
| if (offset >= chip->ngpio) |
| return false; |
| |
| return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_line_is_irq); |
| |
| bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset) |
| { |
| if (offset >= chip->ngpio) |
| return false; |
| |
| return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain); |
| |
| bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset) |
| { |
| if (offset >= chip->ngpio) |
| return false; |
| |
| return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags); |
| } |
| EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source); |
| |
| /** |
| * 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, or negative errno on failure. |
| * |
| * 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); |
| VALIDATE_DESC(desc); |
| 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, or negative errno on failure. |
| * |
| * 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); |
| VALIDATE_DESC(desc); |
| value = _gpiod_get_raw_value(desc); |
| if (value < 0) |
| return value; |
| |
| 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); |
| VALIDATE_DESC_VOID(desc); |
| _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); |
| VALIDATE_DESC_VOID(desc); |
| 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_value_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_value_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_value_priv(true, true, array_size, desc_array, |
| value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); |
| |
| /** |
| * gpiod_set_array_value_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_value_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_value_priv(false, true, array_size, desc_array, |
| value_array); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_set_array_value_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); |
| } |
| |
| /** |
| * gpiod_remove_lookup_table() - unregister GPIO device consumers |
| * @table: table of consumers to unregister |
| */ |
| void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) |
| { |
| mutex_lock(&gpio_lookup_lock); |
| |
| list_del(&table->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) |
| { |
| 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(gpio_suffixes); i++) { |
| if (con_id) |
| snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id, |
| gpio_suffixes[i]); |
| else |
| snprintf(prop_name, sizeof(prop_name), "%s", |
| gpio_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; |
| |
| if (of_flags & OF_GPIO_SINGLE_ENDED) { |
| if (of_flags & OF_GPIO_ACTIVE_LOW) |
| *flags |= GPIO_OPEN_DRAIN; |
| else |
| *flags |= GPIO_OPEN_SOURCE; |
| } |
| |
| return desc; |
| } |
| |
| static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id, |
| unsigned int idx, |
| enum gpio_lookup_flags *flags) |
| { |
| 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(gpio_suffixes); i++) { |
| if (con_id && strcmp(con_id, "gpios")) { |
| snprintf(propname, sizeof(propname), "%s-%s", |
| con_id, gpio_suffixes[i]); |
| } else { |
| snprintf(propname, sizeof(propname), "%s", |
| gpio_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)) { |
| if (!acpi_can_fallback_to_crs(adev, con_id)) |
| return ERR_PTR(-ENOENT); |
| |
| desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info); |
| if (IS_ERR(desc)) |
| return desc; |
| } |
| |
| if (info.polarity == GPIO_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; |
| } |
| |
| static int dt_gpio_count(struct device *dev, const char *con_id) |
| { |
| int ret; |
| char propname[32]; |
| unsigned int i; |
| |
| for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { |
| if (con_id) |
| snprintf(propname, sizeof(propname), "%s-%s", |
| con_id, gpio_suffixes[i]); |
| else |
| snprintf(propname, sizeof(propname), "%s", |
| gpio_suffixes[i]); |
| |
| ret = of_gpio_named_count(dev->of_node, propname); |
| if (ret >= 0) |
| break; |
| } |
| return ret; |
| } |
| |
| static int platform_gpio_count(struct device *dev, const char *con_id) |
| { |
| struct gpiod_lookup_table *table; |
| struct gpiod_lookup *p; |
| unsigned int count = 0; |
| |
| table = gpiod_find_lookup_table(dev); |
| if (!table) |
| return -ENOENT; |
| |
| for (p = &table->table[0]; p->chip_label; p++) { |
| if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || |
| (!con_id && !p->con_id)) |
| count++; |
| } |
| if (!count) |
| return -ENOENT; |
| |
| return count; |
| } |
| |
| /** |
| * 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 |
| */ |
| int gpiod_count(struct device *dev, const char *con_id) |
| { |
| int count = -ENOENT; |
| |
| if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) |
| count = dt_gpio_count(dev, con_id); |
| else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) |
| count = acpi_gpio_count(dev, con_id); |
| |
| if (count < 0) |
| count = platform_gpio_count(dev, con_id); |
| |
| return count; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_count); |
| |
| /** |
| * 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 occurred 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_parse_flags - helper function to parse GPIO lookup flags |
| * @desc: gpio to be setup |
| * @lflags: gpio_lookup_flags - returned from of_find_gpio() or |
| * of_get_gpio_hog() |
| * |
| * Set the GPIO descriptor flags based on the given GPIO lookup flags. |
| */ |
| static void gpiod_parse_flags(struct gpio_desc *desc, unsigned long lflags) |
| { |
| if (lflags & GPIO_ACTIVE_LOW) |
| set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| if (lflags & GPIO_OPEN_DRAIN) |
| set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
| if (lflags & GPIO_OPEN_SOURCE) |
| set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
| } |
| |
| /** |
| * gpiod_configure_flags - helper function to configure a given GPIO |
| * @desc: gpio whose value will be assigned |
| * @con_id: function within the GPIO consumer |
| * @dflags: gpiod_flags - optional GPIO initialization flags |
| * |
| * Return 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. |
| */ |
| static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, |
| enum gpiod_flags dflags) |
| { |
| int status; |
| |
| /* No particular flag request, return here... */ |
| if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { |
| pr_debug("no flags found for %s\n", con_id); |
| return 0; |
| } |
| |
| /* Process flags */ |
| if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) |
| status = gpiod_direction_output(desc, |
| dflags & GPIOD_FLAGS_BIT_DIR_VAL); |
| else |
| status = gpiod_direction_input(desc); |
| |
| return status; |
| } |
| |
| /** |
| * 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 |
| * occurred 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); |
| |
| if (dev) { |
| /* Using device tree? */ |
| if (IS_ENABLED(CONFIG_OF) && dev->of_node) { |
| dev_dbg(dev, "using device tree for GPIO lookup\n"); |
| desc = of_find_gpio(dev, con_id, idx, &lookupflags); |
| } else if (ACPI_COMPANION(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; |
| } |
| |
| gpiod_parse_flags(desc, lookupflags); |
| |
| status = gpiod_request(desc, con_id); |
| if (status < 0) |
| return ERR_PTR(status); |
| |
| status = gpiod_configure_flags(desc, con_id, flags); |
| 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; |
| bool single_ended = 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(to_of_node(fwnode), propname, 0, |
| &flags); |
| if (!IS_ERR(desc)) { |
| active_low = flags & OF_GPIO_ACTIVE_LOW; |
| single_ended = flags & OF_GPIO_SINGLE_ENDED; |
| } |
| } else if (is_acpi_node(fwnode)) { |
| struct acpi_gpio_info info; |
| |
| desc = acpi_node_get_gpiod(fwnode, propname, 0, &info); |
| if (!IS_ERR(desc)) |
| active_low = info.polarity == GPIO_ACTIVE_LOW; |
| } |
| |
| if (IS_ERR(desc)) |
| return desc; |
| |
| if (active_low) |
| set_bit(FLAG_ACTIVE_LOW, &desc->flags); |
| |
| if (single_ended) { |
| if (active_low) |
| set_bit(FLAG_OPEN_DRAIN, &desc->flags); |
| else |
| set_bit(FLAG_OPEN_SOURCE, &desc->flags); |
| } |
| |
| ret = gpiod_request(desc, NULL); |
| if (ret) |
| return ERR_PTR(ret); |
| |
| 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_hog - Hog the specified GPIO desc given the provided flags |
| * @desc: gpio whose value will be assigned |
| * @name: gpio line name |
| * @lflags: gpio_lookup_flags - returned from of_find_gpio() or |
| * of_get_gpio_hog() |
| * @dflags: gpiod_flags - optional GPIO initialization flags |
| */ |
| int gpiod_hog(struct gpio_desc *desc, const char *name, |
| unsigned long lflags, enum gpiod_flags dflags) |
| { |
| struct gpio_chip *chip; |
| struct gpio_desc *local_desc; |
| int hwnum; |
| int status; |
| |
| chip = gpiod_to_chip(desc); |
| hwnum = gpio_chip_hwgpio(desc); |
| |
| gpiod_parse_flags(desc, lflags); |
| |
| local_desc = gpiochip_request_own_desc(chip, hwnum, name); |
| if (IS_ERR(local_desc)) { |
| pr_err("requesting hog GPIO %s (chip %s, offset %d) failed\n", |
| name, chip->label, hwnum); |
| return PTR_ERR(local_desc); |
| } |
| |
| status = gpiod_configure_flags(desc, name, dflags); |
| if (status < 0) { |
| pr_err("setup of hog GPIO %s (chip %s, offset %d) failed\n", |
| name, chip->label, hwnum); |
| gpiochip_free_own_desc(desc); |
| return status; |
| } |
| |
| /* Mark GPIO as hogged so it can be identified and removed later */ |
| set_bit(FLAG_IS_HOGGED, &desc->flags); |
| |
| pr_info("GPIO line %d (%s) hogged as %s%s\n", |
| desc_to_gpio(desc), name, |
| (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", |
| (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? |
| (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":""); |
| |
| return 0; |
| } |
| |
| /** |
| * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog |
| * @chip: gpio chip to act on |
| * |
| * This is only used by of_gpiochip_remove to free hogged gpios |
| */ |
| static void gpiochip_free_hogs(struct gpio_chip *chip) |
| { |
| int id; |
| |
| for (id = 0; id < chip->ngpio; id++) { |
| if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags)) |
| gpiochip_free_own_desc(&chip->gpiodev->descs[id]); |
| } |
| } |
| |
| /** |
| * gpiod_get_array - obtain multiple GPIOs from a multi-index 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 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. |
| */ |
| struct gpio_descs *__must_check gpiod_get_array(struct device *dev, |
| const char *con_id, |
| enum gpiod_flags flags) |
| { |
| struct gpio_desc *desc; |
| struct gpio_descs *descs; |
| int count; |
| |
| count = gpiod_count(dev, con_id); |
| if (count < 0) |
| return ERR_PTR(count); |
| |
| descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count, |
| GFP_KERNEL); |
| if (!descs) |
| return ERR_PTR(-ENOMEM); |
| |
| for (descs->ndescs = 0; descs->ndescs < count; ) { |
| desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); |
| if (IS_ERR(desc)) { |
| gpiod_put_array(descs); |
| return ERR_CAST(desc); |
| } |
| descs->desc[descs->ndescs] = desc; |
| descs->ndescs++; |
| } |
| return descs; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_get_array); |
| |
| /** |
| * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index 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_array(), except that when no GPIO was |
| * assigned to the requested function it will return NULL. |
| */ |
| struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, |
| const char *con_id, |
| enum gpiod_flags flags) |
| { |
| struct gpio_descs *descs; |
| |
| descs = gpiod_get_array(dev, con_id, flags); |
| if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) |
| return NULL; |
| |
| return descs; |
| } |
| EXPORT_SYMBOL_GPL(gpiod_get_array_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); |
| |
| /** |
| * gpiod_put_array - dispose of multiple GPIO descriptors |
| * @descs: struct gpio_descs containing an array of descriptors |
| */ |
| void gpiod_put_array(struct gpio_descs *descs) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < descs->ndescs; i++) |
| gpiod_put(descs->desc[i]); |
| |
| kfree(descs); |
| } |
| EXPORT_SYMBOL_GPL(gpiod_put_array); |
| |
| static int __init gpiolib_dev_init(void) |
| { |
| int ret; |
| |
| /* Register GPIO sysfs bus */ |
| ret = bus_register(&gpio_bus_type); |
| if (ret < 0) { |
| pr_err("gpiolib: could not register GPIO bus type\n"); |
| return ret; |
| } |
| |
| ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip"); |
| if (ret < 0) { |
| pr_err("gpiolib: failed to allocate char dev region\n"); |
| bus_unregister(&gpio_bus_type); |
| } |
| return ret; |
| } |
| core_initcall(gpiolib_dev_init); |
| |
| #ifdef CONFIG_DEBUG_FS |
| |
| static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) |
| { |
| unsigned i; |
| struct gpio_chip *chip = gdev->chip; |
| unsigned gpio = gdev->base; |
| struct gpio_desc *gdesc = &gdev->descs[0]; |
| int is_out; |
| int is_irq; |
| |
| for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) { |
| if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) { |
| if (gdesc->name) { |
| seq_printf(s, " gpio-%-3d (%-20.20s)\n", |
| gpio, gdesc->name); |
| } |
| 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|%-20.20s) %s %s %s", |
| gpio, gdesc->name ? gdesc->name : "", 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_device *gdev = NULL; |
| loff_t index = *pos; |
| |
| s->private = ""; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| list_for_each_entry(gdev, &gpio_devices, list) |
| if (index-- == 0) { |
| spin_unlock_irqrestore(&gpio_lock, flags); |
| return gdev; |
| } |
| 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_device *gdev = v; |
| void *ret = NULL; |
| |
| spin_lock_irqsave(&gpio_lock, flags); |
| if (list_is_last(&gdev->list, &gpio_devices)) |
| ret = NULL; |
| else |
| ret = list_entry(gdev->list.next, struct gpio_device, 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_device *gdev = v; |
| struct gpio_chip *chip = gdev->chip; |
| struct device *parent; |
| |
| if (!chip) { |
| seq_printf(s, "%s%s: (dangling chip)", (char *)s->private, |
| dev_name(&gdev->dev)); |
| return 0; |
| } |
| |
| seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private, |
| dev_name(&gdev->dev), |
| gdev->base, gdev->base + gdev->ngpio - 1); |
| parent = chip->parent; |
| if (parent) |
| seq_printf(s, ", parent: %s/%s", |
| parent->bus ? parent->bus->name : "no-bus", |
| dev_name(parent)); |
| 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, gdev); |
| |
| 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 */ |