Re: [PATCH v2 4/8] usb: chipidea: udc: add suspend/resume support for device controller

[Peter Chen <peter.chen@kernel.org>]

On 22-10-13 23:14:38, Xu Yang wrote:
> The controller's power may be powered off during system suspend. This
> will add suspend/resume support when the controller suffers power lost.
> 
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> 

Acked-by: Peter Chen <peter.chen@kernel.org>

Peter
> ---
> Changes since v1:
> - wrap suspend/resume functions with CONFIG_PM_SLEEP.
> ---
>  drivers/usb/chipidea/udc.c | 32 ++++++++++++++++++++++++++++++++
>  1 file changed, 32 insertions(+)
> 
> diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
> index 8c3e3a635ac2..54c09245ad05 100644
> --- a/drivers/usb/chipidea/udc.c
> +++ b/drivers/usb/chipidea/udc.c
> @@ -2181,6 +2181,34 @@ static void udc_id_switch_for_host(struct ci_hdrc *ci)
>  				     ci->platdata->pins_default);
>  }
>  
> +#ifdef CONFIG_PM_SLEEP
> +static void udc_suspend(struct ci_hdrc *ci)
> +{
> +	/*
> +	 * Set OP_ENDPTLISTADDR to be non-zero for
> +	 * checking if controller resume from power lost
> +	 * in non-host mode.
> +	 */
> +	if (hw_read(ci, OP_ENDPTLISTADDR, ~0) == 0)
> +		hw_write(ci, OP_ENDPTLISTADDR, ~0, ~0);
> +}
> +
> +static void udc_resume(struct ci_hdrc *ci, bool power_lost)
> +{
> +	if (power_lost) {
> +		if (ci->is_otg)
> +			hw_write_otgsc(ci, OTGSC_BSVIS | OTGSC_BSVIE,
> +					OTGSC_BSVIS | OTGSC_BSVIE);
> +		if (ci->vbus_active)
> +			usb_gadget_vbus_disconnect(&ci->gadget);
> +	}
> +
> +	/* Restore value 0 if it was set for power lost check */
> +	if (hw_read(ci, OP_ENDPTLISTADDR, ~0) == 0xFFFFFFFF)
> +		hw_write(ci, OP_ENDPTLISTADDR, ~0, 0);
> +}
> +#endif
> +
>  /**
>   * ci_hdrc_gadget_init - initialize device related bits
>   * @ci: the controller
> @@ -2201,6 +2229,10 @@ int ci_hdrc_gadget_init(struct ci_hdrc *ci)
>  
>  	rdrv->start	= udc_id_switch_for_device;
>  	rdrv->stop	= udc_id_switch_for_host;
> +#ifdef CONFIG_PM_SLEEP
> +	rdrv->suspend	= udc_suspend;
> +	rdrv->resume	= udc_resume;
> +#endif
>  	rdrv->irq	= udc_irq;
>  	rdrv->name	= "gadget";
>  
> -- 
> 2.34.1
> 

-- 

Thanks,
Peter Chen