diff options
| -rw-r--r-- | drivers/gpio/gpiolib.c | 101 |
1 files changed, 48 insertions, 53 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index fc7c4bf2de2b..ef3d66857ad6 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -893,13 +893,15 @@ static const struct device_type gpio_dev_type = { #define gcdev_unregister(gdev) device_del(&(gdev)->dev) #endif +/* + * An initial reference count has been held in gpiochip_add_data_with_key(). + * The caller should drop the reference via gpio_device_put() on errors. + */ static int gpiochip_setup_dev(struct gpio_device *gdev) { struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); int ret; - device_initialize(&gdev->dev); - /* * If fwnode doesn't belong to another device, it's safe to clear its * initialized flag. @@ -965,9 +967,11 @@ static void gpiochip_setup_devs(void) list_for_each_entry_srcu(gdev, &gpio_devices, list, srcu_read_lock_held(&gpio_devices_srcu)) { ret = gpiochip_setup_dev(gdev); - if (ret) + if (ret) { + gpio_device_put(gdev); dev_err(&gdev->dev, "Failed to initialize gpio device (%d)\n", ret); + } } } @@ -1048,71 +1052,72 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, int base = 0; int ret; - /* - * 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.type = &gpio_dev_type; - gdev->dev.bus = &gpio_bus_type; - gdev->dev.parent = gc->parent; - rcu_assign_pointer(gdev->chip, gc); - gc->gpiodev = gdev; gpiochip_set_data(gc, data); - device_set_node(&gdev->dev, gpiochip_choose_fwnode(gc)); - ret = ida_alloc(&gpio_ida, GFP_KERNEL); if (ret < 0) goto err_free_gdev; gdev->id = ret; - ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id); + ret = init_srcu_struct(&gdev->srcu); if (ret) goto err_free_ida; + rcu_assign_pointer(gdev->chip, gc); - if (gc->parent && gc->parent->driver) - gdev->owner = gc->parent->driver->owner; - else if (gc->owner) - /* TODO: remove chip->owner */ - gdev->owner = gc->owner; - else - gdev->owner = THIS_MODULE; + ret = init_srcu_struct(&gdev->desc_srcu); + if (ret) + goto err_cleanup_gdev_srcu; + + ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id); + if (ret) + goto err_cleanup_desc_srcu; + + device_initialize(&gdev->dev); + /* + * After this point any allocated resources to `gdev` will be + * free():ed by gpiodev_release(). If you add new resources + * then make sure they get free():ed there. + */ + gdev->dev.type = &gpio_dev_type; + gdev->dev.bus = &gpio_bus_type; + gdev->dev.parent = gc->parent; + device_set_node(&gdev->dev, gpiochip_choose_fwnode(gc)); ret = gpiochip_get_ngpios(gc, &gdev->dev); if (ret) - goto err_free_dev_name; + goto err_put_device; + gdev->ngpio = gc->ngpio; gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL); if (!gdev->descs) { ret = -ENOMEM; - goto err_free_dev_name; + goto err_put_device; } gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL); if (!gdev->label) { ret = -ENOMEM; - goto err_free_descs; + goto err_put_device; } - gdev->ngpio = gc->ngpio; gdev->can_sleep = gc->can_sleep; - rwlock_init(&gdev->line_state_lock); RAW_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier); BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier); - - ret = init_srcu_struct(&gdev->srcu); - if (ret) - goto err_free_label; - - ret = init_srcu_struct(&gdev->desc_srcu); - if (ret) - goto err_cleanup_gdev_srcu; +#ifdef CONFIG_PINCTRL + INIT_LIST_HEAD(&gdev->pin_ranges); +#endif + if (gc->parent && gc->parent->driver) + gdev->owner = gc->parent->driver->owner; + else if (gc->owner) + /* TODO: remove chip->owner */ + gdev->owner = gc->owner; + else + gdev->owner = THIS_MODULE; scoped_guard(mutex, &gpio_devices_lock) { /* @@ -1128,7 +1133,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, if (base < 0) { ret = base; base = 0; - goto err_cleanup_desc_srcu; + goto err_put_device; } /* @@ -1148,14 +1153,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, ret = gpiodev_add_to_list_unlocked(gdev); if (ret) { gpiochip_err(gc, "GPIO integer space overlap, cannot add chip\n"); - goto err_cleanup_desc_srcu; + goto err_put_device; } } -#ifdef CONFIG_PINCTRL - INIT_LIST_HEAD(&gdev->pin_ranges); -#endif - if (gc->names) gpiochip_set_desc_names(gc); @@ -1249,25 +1250,19 @@ err_remove_from_list: scoped_guard(mutex, &gpio_devices_lock) list_del_rcu(&gdev->list); synchronize_srcu(&gpio_devices_srcu); - if (gdev->dev.release) { - /* release() has been registered by gpiochip_setup_dev() */ - gpio_device_put(gdev); - goto err_print_message; - } +err_put_device: + gpio_device_put(gdev); + goto err_print_message; + err_cleanup_desc_srcu: cleanup_srcu_struct(&gdev->desc_srcu); err_cleanup_gdev_srcu: cleanup_srcu_struct(&gdev->srcu); -err_free_label: - kfree_const(gdev->label); -err_free_descs: - kfree(gdev->descs); -err_free_dev_name: - kfree(dev_name(&gdev->dev)); err_free_ida: ida_free(&gpio_ida, gdev->id); err_free_gdev: kfree(gdev); + err_print_message: /* failures here can mean systems won't boot... */ if (ret != -EPROBE_DEFER) { |