From: Bartosz Golaszewski <[email protected]> Debugfs has become the standard way of interfacing with gpio-mockup to the point where the module is not very useful without it anymore. Let's make it a hard requirement to build gpio-mockup.
Let's also add error checks whenever calling debugfs routines as we now don't expect them to fail. The device sub-directories must now be removed when the device is detached to correctly support dynamically created chips. The call to debugfs_remove_recursive() in module exit must be moved to the bottom or we'd risk to remove the root directory before devices can unregister their own sub-directories. Signed-off-by: Bartosz Golaszewski <[email protected]> --- drivers/gpio/Kconfig | 1 + drivers/gpio/gpio-mockup.c | 41 ++++++++++++++++++++++++++++---------- 2 files changed, 32 insertions(+), 10 deletions(-) diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index 8030fd91a3cc..515f345757d8 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -1567,6 +1567,7 @@ config GPIO_AGGREGATOR config GPIO_MOCKUP tristate "GPIO Testing Driver" + depends on DEBUG_FS select IRQ_SIM help This enables GPIO Testing driver, which provides a way to test GPIO diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c index 29fbf007ab26..7df990662c17 100644 --- a/drivers/gpio/gpio-mockup.c +++ b/drivers/gpio/gpio-mockup.c @@ -348,38 +348,55 @@ static const struct file_operations gpio_mockup_debugfs_ops = { .release = single_release, }; -static void gpio_mockup_debugfs_setup(struct device *dev, - struct gpio_mockup_chip *chip) +static void gpio_mockup_remove_chip_debugfs_entry(void *data) +{ + struct dentry *entry = data; + + debugfs_remove_recursive(entry); +} + +static int gpio_mockup_debugfs_setup(struct device *dev, + struct gpio_mockup_chip *chip) { struct gpio_mockup_dbgfs_private *priv; struct gpio_chip *gc; + struct dentry *attr; const char *devname; char *name; - int i; + int i, ret; gc = &chip->gc; devname = dev_name(&gc->gpiodev->dev); chip->dbg_dir = debugfs_create_dir(devname, gpio_mockup_dbg_dir); + if (IS_ERR(chip->dbg_dir)) + return PTR_ERR(chip->dbg_dir); + + ret = devm_add_action_or_reset(dev, + gpio_mockup_remove_chip_debugfs_entry, chip->dbg_dir); + if (ret) + return ret; for (i = 0; i < gc->ngpio; i++) { name = devm_kasprintf(dev, GFP_KERNEL, "%d", i); if (!name) - return; + return -ENOMEM; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) - return; + return -ENOMEM; priv->chip = chip; priv->offset = i; priv->desc = &gc->gpiodev->descs[i]; - debugfs_create_file(name, 0200, chip->dbg_dir, priv, - &gpio_mockup_debugfs_ops); + attr = debugfs_create_file(name, 0200, chip->dbg_dir, priv, + &gpio_mockup_debugfs_ops); + if (IS_ERR(attr)) + return PTR_ERR(attr); } - return; + return 0; } static void gpio_mockup_dispose_mappings(void *data) @@ -462,7 +479,9 @@ static int gpio_mockup_probe(struct platform_device *pdev) if (rv) return rv; - gpio_mockup_debugfs_setup(dev, chip); + rv = gpio_mockup_debugfs_setup(dev, chip); + if (rv) + return rv; return 0; } @@ -629,6 +648,8 @@ static int __init gpio_mockup_init(void) int ret; gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup", NULL); + if (IS_ERR(gpio_mockup_dbg_dir)) + return PTR_ERR(gpio_mockup_dbg_dir); ret = platform_driver_register(&gpio_mockup_driver); if (ret) { @@ -650,9 +671,9 @@ static int __init gpio_mockup_init(void) static void __exit gpio_mockup_exit(void) { - debugfs_remove_recursive(gpio_mockup_dbg_dir); platform_driver_unregister(&gpio_mockup_driver); gpio_mockup_unregister_devices(); + debugfs_remove_recursive(gpio_mockup_dbg_dir); } module_init(gpio_mockup_init); -- 2.26.1
