[PATCH V3 7/9] usb: dwc2: Refactor backup/restore of registers

[Stefan Wahren]

Am 21.08.24 um 23:40 schrieb Stefan Wahren:
> The DWC2 runtime PM code reuses similar patterns to backup and
> restore the registers. So consolidate them in USB mode specific
> variants. This also has the advantage it is usable for further
> PM improvements.
>
> Signed-off-by: Stefan Wahren <wahrenst at gmx.net>
> ---
>   drivers/usb/dwc2/core.h   |  12 +++++
>   drivers/usb/dwc2/gadget.c | 101 +++++++++++++++++++-------------------
>   drivers/usb/dwc2/hcd.c    |  99 +++++++++++++++++++------------------
>   3 files changed, 114 insertions(+), 98 deletions(-)
>
> diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
> index 2bd74f3033ed..81e8632f29ed 100644
> --- a/drivers/usb/dwc2/core.h
> +++ b/drivers/usb/dwc2/core.h
> @@ -1435,6 +1435,8 @@ int dwc2_hsotg_tx_fifo_total_depth(struct dwc2_hsotg *hsotg);
>   int dwc2_hsotg_tx_fifo_average_depth(struct dwc2_hsotg *hsotg);
>   void dwc2_gadget_init_lpm(struct dwc2_hsotg *hsotg);
>   void dwc2_gadget_program_ref_clk(struct dwc2_hsotg *hsotg);
> +int dwc2_gadget_backup_critical_registers(struct dwc2_hsotg *hsotg);
> +int dwc2_gadget_restore_critical_registers(struct dwc2_hsotg *hsotg);
>   static inline void dwc2_clear_fifo_map(struct dwc2_hsotg *hsotg)
>   { hsotg->fifo_map = 0; }
>   #else
> @@ -1482,6 +1484,10 @@ static inline int dwc2_hsotg_tx_fifo_average_depth(struct dwc2_hsotg *hsotg)
>   { return 0; }
>   static inline void dwc2_gadget_init_lpm(struct dwc2_hsotg *hsotg) {}
>   static inline void dwc2_gadget_program_ref_clk(struct dwc2_hsotg *hsotg) {}
> +static inline int dwc2_gadget_backup_critical_registers(struct dwc2_hsotg *hsotg)
> +{ return 0; }
> +static inline int dwc2_gadget_restore_critical_registers(struct dwc2_hsotg *hsotg)
> +{ return 0; }
>   static inline void dwc2_clear_fifo_map(struct dwc2_hsotg *hsotg) {}
>   #endif
>
> @@ -1505,6 +1511,8 @@ int dwc2_host_exit_partial_power_down(struct dwc2_hsotg *hsotg,
>   void dwc2_host_enter_clock_gating(struct dwc2_hsotg *hsotg);
>   void dwc2_host_exit_clock_gating(struct dwc2_hsotg *hsotg, int rem_wakeup);
>   bool dwc2_host_can_poweroff_phy(struct dwc2_hsotg *dwc2);
> +int dwc2_host_backup_critical_registers(struct dwc2_hsotg *hsotg);
> +int dwc2_host_restore_critical_registers(struct dwc2_hsotg *hsotg);
>   static inline void dwc2_host_schedule_phy_reset(struct dwc2_hsotg *hsotg)
>   { schedule_work(&hsotg->phy_reset_work); }
>   #else
> @@ -1544,6 +1552,10 @@ static inline void dwc2_host_exit_clock_gating(struct dwc2_hsotg *hsotg,
>   					       int rem_wakeup) {}
>   static inline bool dwc2_host_can_poweroff_phy(struct dwc2_hsotg *dwc2)
>   { return false; }
> +static inline int dwc2_host_backup_critical_registers(struct dwc2_hsotg *hsotg)
> +{ return 0; }
> +static inline int dwc2_host_restore_critical_registers(struct dwc2_hsotg *hsotg)
> +{ return 0; }
>   static inline void dwc2_host_schedule_phy_reset(struct dwc2_hsotg *hsotg) {}
>
>   #endif
> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
> index e7bf9cc635be..0bff748bcf74 100644
> --- a/drivers/usb/dwc2/gadget.c
> +++ b/drivers/usb/dwc2/gadget.c
> @@ -5309,6 +5309,49 @@ void dwc2_gadget_program_ref_clk(struct dwc2_hsotg *hsotg)
>   	dev_dbg(hsotg->dev, "GREFCLK=0x%08x\n", dwc2_readl(hsotg, GREFCLK));
>   }
>
> +int dwc2_gadget_backup_critical_registers(struct dwc2_hsotg *hsotg)
> +{
> +	int ret;
> +
> +	/* Backup all registers */
> +	ret = dwc2_backup_global_registers(hsotg);
> +	if (ret) {
> +		dev_err(hsotg->dev, "%s: failed to backup global registers\n",
> +			__func__);
> +		return ret;
> +	}
> +
> +	ret = dwc2_backup_device_registers(hsotg);
> +	if (ret) {
> +		dev_err(hsotg->dev, "%s: failed to backup device registers\n",
> +			__func__);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +int dwc2_gadget_restore_critical_registers(struct dwc2_hsotg *hsotg)
> +{
> +	int ret;
> +
> +	ret = dwc2_restore_global_registers(hsotg);
> +	if (ret) {
> +		dev_err(hsotg->dev, "%s: failed to restore registers\n",
> +			__func__);
> +		return ret;
> +	}
> +
> +	ret = dwc2_restore_device_registers(hsotg, 0);
> +	if (ret) {
> +		dev_err(hsotg->dev, "%s: failed to restore device registers\n",
> +			__func__);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
>   /**
>    * dwc2_gadget_enter_hibernation() - Put controller in Hibernation.
>    *
> @@ -5326,18 +5369,9 @@ int dwc2_gadget_enter_hibernation(struct dwc2_hsotg *hsotg)
>   	/* Change to L2(suspend) state */
>   	hsotg->lx_state = DWC2_L2;
>   	dev_dbg(hsotg->dev, "Start of hibernation completed\n");
> -	ret = dwc2_backup_global_registers(hsotg);
> -	if (ret) {
> -		dev_err(hsotg->dev, "%s: failed to backup global registers\n",
> -			__func__);
> -		return ret;
> -	}
> -	ret = dwc2_backup_device_registers(hsotg);
> -	if (ret) {
> -		dev_err(hsotg->dev, "%s: failed to backup device registers\n",
> -			__func__);
> +	ret = dwc2_gadget_backup_critical_registers(hsotg);
> +	if (ret)
>   		return ret;
> -	}
>
>   	gpwrdn = GPWRDN_PWRDNRSTN;
>   	udelay(10);
> @@ -5483,20 +5517,9 @@ int dwc2_gadget_exit_hibernation(struct dwc2_hsotg *hsotg,
>   	dwc2_writel(hsotg, 0xffffffff, GINTSTS);
>
>   	/* Restore global registers */
> -	ret = dwc2_restore_global_registers(hsotg);
> -	if (ret) {
> -		dev_err(hsotg->dev, "%s: failed to restore registers\n",
> -			__func__);
> -		return ret;
> -	}
> -
> -	/* Restore device registers */
> -	ret = dwc2_restore_device_registers(hsotg, rem_wakeup);
> -	if (ret) {
> -		dev_err(hsotg->dev, "%s: failed to restore device registers\n",
> -			__func__);
> +	ret = dwc2_gadget_restore_critical_registers(hsotg);
> +	if (ret)
>   		return ret;
> -	}
>
>   	if (rem_wakeup) {
>   		mdelay(10);
> @@ -5530,19 +5553,9 @@ int dwc2_gadget_enter_partial_power_down(struct dwc2_hsotg *hsotg)
>   	dev_dbg(hsotg->dev, "Entering device partial power down started.\n");
>
>   	/* Backup all registers */
> -	ret = dwc2_backup_global_registers(hsotg);
> -	if (ret) {
> -		dev_err(hsotg->dev, "%s: failed to backup global registers\n",
> -			__func__);
> -		return ret;
> -	}
> -
> -	ret = dwc2_backup_device_registers(hsotg);
> -	if (ret) {
> -		dev_err(hsotg->dev, "%s: failed to backup device registers\n",
> -			__func__);
> +	ret = dwc2_gadget_backup_critical_registers(hsotg);
> +	if (ret)
>   		return ret;
> -	}
>
>   	/*
>   	 * Clear any pending interrupts since dwc2 will not be able to
> @@ -5610,21 +5623,9 @@ int dwc2_gadget_exit_partial_power_down(struct dwc2_hsotg *hsotg,
>
>   	udelay(100);
>   	if (restore) {
> -		ret = dwc2_restore_global_registers(hsotg);
> -		if (ret) {
> -			dev_err(hsotg->dev, "%s: failed to restore registers\n",
> -				__func__);
> -			return ret;
> -		}
> -		/* Restore DCFG */
> -		dwc2_writel(hsotg, dr->dcfg, DCFG);
Oh dear, i accidentally dropped that. I will fix this.

Thanks goes to kernel test robot