Re: [PATCH 04/29] drivers: base: add notifier for failed driver bind

Laurent Pinchart
2014-08-21T19:45:52Z

Hi Marek,

Thank you for the patch.

On Tuesday 05 August 2014 12:47:32 Marek Szyprowski wrote:
> This patch adds support for getting a notify for failed device driver
> bind, so all the items done in BUS_NOTIFY_BIND_DRIVER event can be
> cleaned if the driver fails to bind.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
> drivers/base/dd.c | 10 +++++++---
> include/linux/device.h | 4 +++-
> 2 files changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/base/dd.c b/drivers/base/dd.c
> index e4ffbcf..541a41f 100644
> --- a/drivers/base/dd.c
> +++ b/drivers/base/dd.c
> @@ -237,10 +237,14 @@ static int driver_sysfs_add(struct device *dev)
> return ret;
> }
>
> -static void driver_sysfs_remove(struct device *dev)
> +static void driver_sysfs_remove(struct device *dev, int failed)
> {
> struct device_driver *drv = dev->driver;
>
> + if (failed && dev->bus)
> + blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
> + BUS_NOTIFY_DRVBIND_FAILED, dev);

This might be a stupid question, but as you only call driver_sysfs_remove with
failed set to true in a single location (in the failure path of really_probe),
how about moving the blocking_notifier_call_chain to that location ? The code
seems to be a bit out of place here.

> +
> if (drv) {
> sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj));
> sysfs_remove_link(&dev->kobj, "driver");
> @@ -316,7 +320,7 @@ static int really_probe(struct device *dev, struct
> device_driver *drv)
>
> probe_failed:
> devres_release_all(dev);
> - driver_sysfs_remove(dev);
> + driver_sysfs_remove(dev, true);
> dev->driver = NULL;
> dev_set_drvdata(dev, NULL);
>
> @@ -509,7 +513,7 @@ static void __device_release_driver(struct device *dev)
> if (drv) {
> pm_runtime_get_sync(dev);
>
> - driver_sysfs_remove(dev);
> + driver_sysfs_remove(dev, false);
>
> if (dev->bus)
> blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
> diff --git a/include/linux/device.h b/include/linux/device.h
> index b387710..92daded 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -176,7 +176,7 @@ extern int bus_register_notifier(struct bus_type *bus,
> extern int bus_unregister_notifier(struct bus_type *bus,
> struct notifier_block *nb);
>
> -/* All 4 notifers below get called with the target struct device *
> +/* All 7 notifers below get called with the target struct device *
> * as an argument. Note that those functions are likely to be called
> * with the device lock held in the core, so be careful.
> */
> @@ -189,6 +189,8 @@ extern int bus_unregister_notifier(struct bus_type *bus,
> unbound */
> #define BUS_NOTIFY_UNBOUND_DRIVER 0x00000006 /* driver is unbound
> from the device */
> +#define BUS_NOTIFY_DRVBIND_FAILED 0x00000007 /* driver failed to bind
> + to device */
>
> extern struct kset *bus_get_kset(struct bus_type *bus);
> extern struct klist *bus_get_device_klist(struct bus_type *bus);

--
Regards,

Laurent Pinchart