Re: [PATCH] usb: gadget: f_mass_storage: forced_eject attribute

[Greg KH <gregkh@linuxfoundation.org>]

On Wed, Jul 06, 2022 at 08:46:34PM +0300, Maxim Devaev wrote:
> It allows to reset prevent_medium_removal flag and "eject" the image.
> 
> The patch is a completely alternative implementation of the previously
> proposed [1], the idea of which was born after the mentioned discussion.
> 
> Signed-off-by: Maxim Devaev <mdevaev@gmail.com>
> Link: https://lore.kernel.org/lkml/20220406092445.215288-1-mdevaev@gmail.com [1]
> ---
>  drivers/usb/gadget/function/f_mass_storage.c | 25 ++++++++++++++++++++
>  drivers/usb/gadget/function/storage_common.c | 11 +++++++++
>  drivers/usb/gadget/function/storage_common.h |  2 ++
>  3 files changed, 38 insertions(+)
> 
> diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
> index 6ad669dde41c..00cac2a38178 100644
> --- a/drivers/usb/gadget/function/f_mass_storage.c
> +++ b/drivers/usb/gadget/function/f_mass_storage.c
> @@ -2520,10 +2520,21 @@ static ssize_t file_store(struct device *dev, struct device_attribute *attr,
>  	return fsg_store_file(curlun, filesem, buf, count);
>  }
>  
> +static ssize_t forced_eject_store(struct device *dev,
> +				  struct device_attribute *attr,
> +				  const char *buf, size_t count)
> +{
> +	struct fsg_lun		*curlun = fsg_lun_from_dev(dev);
> +	struct rw_semaphore	*filesem = dev_get_drvdata(dev);
> +
> +	return fsg_store_forced_eject(curlun, filesem, buf, count);
> +}
> +
>  static DEVICE_ATTR_RW(nofua);
>  /* mode wil be set in fsg_lun_attr_is_visible() */
>  static DEVICE_ATTR(ro, 0, ro_show, ro_store);
>  static DEVICE_ATTR(file, 0, file_show, file_store);
> +static DEVICE_ATTR_WO(forced_eject);

You have to document sysfs files in Documentation/ABI/ in order for us
to be able to accept them.

thanks,

greg k-h