Re: [PATCH] USB: core: add 'shutdown' callback to usb_driver

Aditya Garg
2024-07-05T11:22:47Z

Replying to this since I forgot to add the author Kerem Karabay to cc, so adding now

> On 5 Jul 2024, at 4:50 PM, Aditya Garg <gargaditya08@live.com> wrote:
>
> From: Kerem Karabay <kekrby@gmail.com>
>
> This simplifies running code on shutdown for USB drivers.
>
> Signed-off-by: Kerem Karabay <kekrby@gmail.com>
> Signed-off-by: Aditya Garg <gargaditya08@live.com>
> ---
> drivers/usb/core/driver.c | 14 ++++++++++++++
> drivers/usb/storage/uas.c | 5 ++---
> include/linux/usb.h | 3 +++
> 3 files changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
> index f58a0299f..dc0f86376 100644
> --- a/drivers/usb/core/driver.c
> +++ b/drivers/usb/core/driver.c
> @@ -514,6 +514,19 @@ static int usb_unbind_interface(struct device *dev)
> return 0;
> }
>
> +static void usb_shutdown_interface(struct device *dev)
> +{
> + struct usb_interface *intf = to_usb_interface(dev);
> + struct usb_driver *driver;
> +
> + if (!dev->driver)
> + return;
> +
> + driver = to_usb_driver(dev->driver);
> + if (driver->shutdown)
> + driver->shutdown(intf);
> +}
> +
> /**
> * usb_driver_claim_interface - bind a driver to an interface
> * @driver: the driver to be bound
> @@ -1053,6 +1066,7 @@ int usb_register_driver(struct usb_driver *new_driver, struct module *owner,
> new_driver->driver.bus = &usb_bus_type;
> new_driver->driver.probe = usb_probe_interface;
> new_driver->driver.remove = usb_unbind_interface;
> + new_driver->driver.shutdown = usb_shutdown_interface;
> new_driver->driver.owner = owner;
> new_driver->driver.mod_name = mod_name;
> new_driver->driver.dev_groups = new_driver->dev_groups;
> diff --git a/drivers/usb/storage/uas.c b/drivers/usb/storage/uas.c
> index 2583ee981..591fa0379 100644
> --- a/drivers/usb/storage/uas.c
> +++ b/drivers/usb/storage/uas.c
> @@ -1221,9 +1221,8 @@ static void uas_disconnect(struct usb_interface *intf)
> * hang on reboot when the device is still in uas mode. Note the reset is
> * necessary as some devices won't revert to usb-storage mode without it.
> */
> -static void uas_shutdown(struct device *dev)
> +static void uas_shutdown(struct usb_interface *intf)
> {
> - struct usb_interface *intf = to_usb_interface(dev);
> struct usb_device *udev = interface_to_usbdev(intf);
> struct Scsi_Host *shost = usb_get_intfdata(intf);
> struct uas_dev_info *devinfo = (struct uas_dev_info *)shost->hostdata;
> @@ -1246,7 +1245,7 @@ static struct usb_driver uas_driver = {
> .suspend = uas_suspend,
> .resume = uas_resume,
> .reset_resume = uas_reset_resume,
> - .driver.shutdown = uas_shutdown,
> + .shutdown = uas_shutdown,
> .id_table = uas_usb_ids,
> };
>
> diff --git a/include/linux/usb.h b/include/linux/usb.h
> index 25f8e62a3..5f3ae2186 100644
> --- a/include/linux/usb.h
> +++ b/include/linux/usb.h
> @@ -1194,6 +1194,7 @@ struct usbdrv_wrap {
> * post_reset method is called.
> * @post_reset: Called by usb_reset_device() after the device
> * has been reset
> + * @shutdown: Called at shut-down time to quiesce the device.
> * @id_table: USB drivers use ID table to support hotplugging.
> * Export this with MODULE_DEVICE_TABLE(usb,...). This must be set
> * or your driver's probe function will never get called.
> @@ -1245,6 +1246,8 @@ struct usb_driver {
> int (*pre_reset)(struct usb_interface *intf);
> int (*post_reset)(struct usb_interface *intf);
>
> + void (*shutdown)(struct usb_interface *intf);
> +
> const struct usb_device_id *id_table;
> const struct attribute_group **dev_groups;
>
> --
> 2.42.0
>