On 4/8/2021 1:45 PM, Artur Petrosyan wrote:
> With current implementation the port power is being disabled,
> which is not required by the programming guide. Also, if there
> is a system which works only in "DWC2_POWER_DOWN_PARAM_NONE"
> (clock gating) mode the current implementation does not set
> Gate hclk bit in pcgctl register.
>
> Rearranges and updates the implementation of entering to partial
> power down power saving mode when PC is suspended to get
> rid of many "if" statements and removes disabling of port power.
>
> NOTE: Switch case statement is used for hibernation partial
> power down and clock gating mode determination. In this patch
> only Partial Power Down is implemented the Hibernation and
> clock gating implementations are planned to be added.
>
> Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@xxxxxxxxxxxx>
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@xxxxxxxxxxxx>
> ---
> Changes in v3:
> - None
> Changes in v2:
> - None
>
> drivers/usb/dwc2/hcd.c | 53 ++++++++++++++----------------------------
> 1 file changed, 18 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
> index cb52bc41bfb8..34030bafdff4 100644
> --- a/drivers/usb/dwc2/hcd.c
> +++ b/drivers/usb/dwc2/hcd.c
> @@ -4367,8 +4367,6 @@ static int _dwc2_hcd_suspend(struct usb_hcd *hcd)
> struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);
> unsigned long flags;
> int ret = 0;
> - u32 hprt0;
> - u32 pcgctl;
>
> spin_lock_irqsave(&hsotg->lock, flags);
>
> @@ -4384,47 +4382,32 @@ static int _dwc2_hcd_suspend(struct usb_hcd *hcd)
> if (hsotg->op_state == OTG_STATE_B_PERIPHERAL)
> goto unlock;
>
> - if (hsotg->params.power_down != DWC2_POWER_DOWN_PARAM_PARTIAL ||
> - hsotg->flags.b.port_connect_status == 0)
> + if (hsotg->bus_suspended)
> goto skip_power_saving;
>
> - /*
> - * Drive USB suspend and disable port Power
> - * if usb bus is not suspended.
> - */
> - if (!hsotg->bus_suspended) {
> - hprt0 = dwc2_read_hprt0(hsotg);
> - if (hprt0 & HPRT0_CONNSTS) {
> - hprt0 |= HPRT0_SUSP;
> - if (hsotg->params.power_down == DWC2_POWER_DOWN_PARAM_PARTIAL)
> - hprt0 &= ~HPRT0_PWR;
> - dwc2_writel(hsotg, hprt0, HPRT0);
> - }
> - if (hsotg->params.power_down == DWC2_POWER_DOWN_PARAM_PARTIAL) {
> - spin_unlock_irqrestore(&hsotg->lock, flags);
> - dwc2_vbus_supply_exit(hsotg);
> - spin_lock_irqsave(&hsotg->lock, flags);
> - } else {
> - pcgctl = readl(hsotg->regs + PCGCTL);
> - pcgctl |= PCGCTL_STOPPCLK;
> - writel(pcgctl, hsotg->regs + PCGCTL);
> - }
> - }
> + if (hsotg->flags.b.port_connect_status == 0)
> + goto skip_power_saving;
>
> - if (hsotg->params.power_down == DWC2_POWER_DOWN_PARAM_PARTIAL) {
> + switch (hsotg->params.power_down) {
> + case DWC2_POWER_DOWN_PARAM_PARTIAL:
> /* Enter partial_power_down */
> ret = dwc2_enter_partial_power_down(hsotg);
> - if (ret) {
> - if (ret != -ENOTSUPP)
> - dev_err(hsotg->dev,
> - "enter partial_power_down failed\n");
> - goto skip_power_saving;
> - }
> -
> - /* After entering partial_power_down, hardware is no more accessible */
> + if (ret)
> + dev_err(hsotg->dev,
> + "enter partial_power_down failed\n");
> + /* After entering suspend, hardware is not accessible */
> clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
> + break;
> + case DWC2_POWER_DOWN_PARAM_HIBERNATION:
> + case DWC2_POWER_DOWN_PARAM_NONE:
> + default:
> + goto skip_power_saving;
> }
>
> + spin_unlock_irqrestore(&hsotg->lock, flags);
> + dwc2_vbus_supply_exit(hsotg);
> + spin_lock_irqsave(&hsotg->lock, flags);
> +
> /* Ask phy to be suspended */
> if (!IS_ERR_OR_NULL(hsotg->uphy)) {
> spin_unlock_irqrestore(&hsotg->lock, flags);
>
