diff options
| -rw-r--r-- | drivers/gpio/gpiolib.c | 98 |
1 files changed, 67 insertions, 31 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 5ca7c9aa4fab..b747c76fd2b1 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -68,6 +68,7 @@ LIST_HEAD(gpio_devices); static void gpiochip_free_hogs(struct gpio_chip *chip); static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); +static bool gpiolib_initialized; static inline void desc_set_label(struct gpio_desc *d, const char *label) { @@ -445,6 +446,58 @@ static void gpiodevice_release(struct device *dev) kfree(gdev); } +static int gpiochip_setup_dev(struct gpio_device *gdev) +{ + int status; + + 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(gdev->chip, "failed to add char device %d:%d\n", + MAJOR(gpio_devt), gdev->id); + else + chip_dbg(gdev->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), gdev->chip->label ? : "generic"); + + return 0; + +err_remove_device: + device_del(&gdev->dev); +err_remove_chardev: + cdev_del(&gdev->chrdev); + return status; +} + +static void gpiochip_setup_devs(void) +{ + struct gpio_device *gdev; + int err; + + list_for_each_entry(gdev, &gpio_devices, list) { + err = gpiochip_setup_dev(gdev); + if (err) + pr_err("%s: Failed to initialize gpio device (%d)\n", + dev_name(&gdev->dev), err); + } +} + /** * gpiochip_add_data() - register a gpio_chip * @chip: the chip to register, with chip->base initialized @@ -459,6 +512,9 @@ static void gpiodevice_release(struct device *dev) * the gpio framework's arch_initcall(). Otherwise sysfs initialization * for GPIOs will fail rudely. * + * gpiochip_add_data() must only be called after gpiolib initialization, + * ie after core_initcall(). + * * If chip->base is negative, this requests dynamic assignment of * a range of valid GPIOs. */ @@ -515,7 +571,7 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data) if (chip->ngpio == 0) { chip_err(chip, "tried to insert a GPIO chip with zero lines\n"); status = -EINVAL; - goto err_free_gdev; + goto err_free_descs; } if (chip->label) @@ -597,39 +653,16 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data) * 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. + * We can do this only if gpiolib has been initialized. + * Otherwise, defer until later. */ - 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"); - + if (gpiolib_initialized) { + status = gpiochip_setup_dev(gdev); + if (status) + goto err_remove_chip; + } 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); @@ -2842,6 +2875,9 @@ static int __init gpiolib_dev_init(void) if (ret < 0) { pr_err("gpiolib: failed to allocate char dev region\n"); bus_unregister(&gpio_bus_type); + } else { + gpiolib_initialized = true; + gpiochip_setup_devs(); } return ret; } |