From: Greg Kroah-Hartman gregkh@linuxfoundation.org
[ Upstream commit 21b0dc55bed6d9b5dd5d1ad22b75d9d1c7426bbc ]
It's really hard to know if a faux device properly passes the callback to probe() without having to poke around in the faux_device structure and then clean up. Instead of having to have every user of the api do this logic, just do it in the faux device core itself.
This makes the use of a custom probe() callback for a faux device much simpler overall.
Suggested-by: Kurt Borja kuurtb@gmail.com Cc: Rafael J. Wysocki rafael@kernel.org Reviewed-by: Kurt Borja kuurtb@gmail.com Reviewed-by: Danilo Krummrich dakr@kernel.org Link: https://lore.kernel.org/r/2025022545-unroasted-common-fa0e@gregkh Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/base/faux.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/base/faux.c b/drivers/base/faux.c index 531e9d789ee04..407c1d1aad50b 100644 --- a/drivers/base/faux.c +++ b/drivers/base/faux.c @@ -102,7 +102,9 @@ static void faux_device_release(struct device *dev) * * Note, when this function is called, the functions specified in struct * faux_ops can be called before the function returns, so be prepared for - * everything to be properly initialized before that point in time. + * everything to be properly initialized before that point in time. If the + * probe callback (if one is present) does NOT succeed, the creation of the + * device will fail and NULL will be returned. * * Return: * * NULL if an error happened with creating the device @@ -147,6 +149,17 @@ struct faux_device *faux_device_create_with_groups(const char *name, return NULL; }
+ /* + * Verify that we did bind the driver to the device (i.e. probe worked), + * if not, let's fail the creation as trying to guess if probe was + * successful is almost impossible to determine by the caller. + */ + if (!dev->driver) { + dev_err(dev, "probe did not succeed, tearing down the device\n"); + faux_device_destroy(faux_dev); + faux_dev = NULL; + } + return faux_dev; } EXPORT_SYMBOL_GPL(faux_device_create_with_groups);