Re: [PATCH 2/3] usb: common: add helper to get role-switch-default-mode

[Greg Kroah-Hartman]

On Tue, May 25, 2021 at 04:59:24PM +0800, Chunfeng Yun wrote:
> Add helper to get "role-switch-default-mode", and convert it
> to the corresponding enum usb_dr_mode
> 
> Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
> ---
>  drivers/usb/common/common.c | 20 ++++++++++++++++++++
>  include/linux/usb/otg.h     |  1 +
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
> index fff318597337..78a625a4e526 100644
> --- a/drivers/usb/common/common.c
> +++ b/drivers/usb/common/common.c
> @@ -207,6 +207,26 @@ enum usb_dr_mode usb_get_dr_mode(struct device *dev)
>  }
>  EXPORT_SYMBOL_GPL(usb_get_dr_mode);
>  
> +/**
> + * usb_get_role_switch_default_mode - Get default mode for given device
> + * @dev: Pointer to the given device
> + *
> + * The function gets string from property 'role-switch-default-mode',
> + * and returns the corresponding enum usb_dr_mode.
> + */
> +enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev)
> +{
> +	const char *str;
> +	int ret;
> +
> +	ret = device_property_read_string(dev, "role-switch-default-mode", &str);
> +	if (ret < 0)
> +		return USB_DR_MODE_UNKNOWN;
> +
> +	return usb_get_dr_mode_from_string(str);
> +}
> +EXPORT_SYMBOL_GPL(usb_get_role_switch_default_mode);
> +
>  /**
>   * usb_decode_interval - Decode bInterval into the time expressed in 1us unit
>   * @epd: The descriptor of the endpoint
> diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h
> index a86ee6aad51b..bde313c97fb6 100644
> --- a/include/linux/usb/otg.h
> +++ b/include/linux/usb/otg.h
> @@ -121,5 +121,6 @@ enum usb_dr_mode {
>  };
>  
>  extern enum usb_dr_mode usb_get_dr_mode(struct device *dev);
> +extern enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev);

What other code outside of the dwc3 driver will ever need to call this?

thanks,

greg k-h