linux-kernel - Re: [PATCH v9 3/5] usb: dwc3: qcom: Add helper functions to enable,disable wake irqs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YYAYNWCpzCbYe82i@ripper>
Date:   Mon, 1 Nov 2021 09:39:17 -0700
From:   Bjorn Andersson <bjorn.andersson@...aro.org>
To:     Sandeep Maheswaram <quic_c_sanm@...cinc.com>
Cc:     Andy Gross <agross@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Felipe Balbi <balbi@...nel.org>,
        Stephen Boyd <swboyd@...omium.org>,
        Doug Anderson <dianders@...omium.org>,
        Matthias Kaehlcke <mka@...omium.org>,
        Mathias Nyman <mathias.nyman@...el.com>,
        linux-arm-msm@...r.kernel.org, linux-usb@...r.kernel.org,
        linux-kernel@...r.kernel.org, quic_pkondeti@...cinc.com,
        quic_ppratap@...cinc.com
Subject: Re: [PATCH v9 3/5] usb: dwc3: qcom: Add helper functions to
 enable,disable wake irqs

On Mon 01 Nov 00:53 PDT 2021, Sandeep Maheswaram wrote:

> Adding helper functions to enable,disable wake irqs to make
> the code simple and readable.
> 
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@...cinc.com>
> Reviewed-by: Matthias Kaehlcke <mka@...omium.org>
> ---
>  drivers/usb/dwc3/dwc3-qcom.c | 58 ++++++++++++++++++++------------------------
>  1 file changed, 26 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
> index 9abbd01..54461f1 100644
> --- a/drivers/usb/dwc3/dwc3-qcom.c
> +++ b/drivers/usb/dwc3/dwc3-qcom.c
> @@ -296,50 +296,44 @@ static void dwc3_qcom_interconnect_exit(struct dwc3_qcom *qcom)
>  	icc_put(qcom->icc_path_apps);
>  }
>  
> +static void dwc3_qcom_enable_wakeup_irq(int irq)
> +{
> +	if (!irq)
> +		return;
> +
> +	enable_irq(irq);
> +	enable_irq_wake(irq);
> +}
> +
> +static void dwc3_qcom_disable_wakeup_irq(int irq)
> +{
> +	if (!irq)
> +		return;
> +
> +	disable_irq_wake(irq);

Now that you touch this code path.

I presume keeping these interrupts enabled during runtime would cause
the interrupt to fire during normal operation, but why do we need to
toggle the irq_wake? Can't we just leave that flag set always?

> +	disable_irq_nosync(irq);
> +}
> +
>  static void dwc3_qcom_disable_interrupts(struct dwc3_qcom *qcom)
>  {
> -	if (qcom->hs_phy_irq) {
> -		disable_irq_wake(qcom->hs_phy_irq);
> -		disable_irq_nosync(qcom->hs_phy_irq);
> -	}
> +	dwc3_qcom_disable_wakeup_irq(qcom->hs_phy_irq);

Why don't we just replace *_phy_irq with an array and turn these two
function into two loops? That seems to be quite suitable for the
multi-port dwc found in e.g. sc8180x as well...

Regards,
Bjorn

>  
> -	if (qcom->dp_hs_phy_irq) {
> -		disable_irq_wake(qcom->dp_hs_phy_irq);
> -		disable_irq_nosync(qcom->dp_hs_phy_irq);
> -	}
> +	dwc3_qcom_disable_wakeup_irq(qcom->dp_hs_phy_irq);
>  
> -	if (qcom->dm_hs_phy_irq) {
> -		disable_irq_wake(qcom->dm_hs_phy_irq);
> -		disable_irq_nosync(qcom->dm_hs_phy_irq);
> -	}
> +	dwc3_qcom_disable_wakeup_irq(qcom->dm_hs_phy_irq);
>  
> -	if (qcom->ss_phy_irq) {
> -		disable_irq_wake(qcom->ss_phy_irq);
> -		disable_irq_nosync(qcom->ss_phy_irq);
> -	}
> +	dwc3_qcom_disable_wakeup_irq(qcom->ss_phy_irq);
>  }
>  
>  static void dwc3_qcom_enable_interrupts(struct dwc3_qcom *qcom)
>  {
> -	if (qcom->hs_phy_irq) {
> -		enable_irq(qcom->hs_phy_irq);
> -		enable_irq_wake(qcom->hs_phy_irq);
> -	}
> +	dwc3_qcom_enable_wakeup_irq(qcom->hs_phy_irq);
>  
> -	if (qcom->dp_hs_phy_irq) {
> -		enable_irq(qcom->dp_hs_phy_irq);
> -		enable_irq_wake(qcom->dp_hs_phy_irq);
> -	}
> +	dwc3_qcom_enable_wakeup_irq(qcom->dp_hs_phy_irq);
>  
> -	if (qcom->dm_hs_phy_irq) {
> -		enable_irq(qcom->dm_hs_phy_irq);
> -		enable_irq_wake(qcom->dm_hs_phy_irq);
> -	}
> +	dwc3_qcom_enable_wakeup_irq(qcom->dm_hs_phy_irq);
>  
> -	if (qcom->ss_phy_irq) {
> -		enable_irq(qcom->ss_phy_irq);
> -		enable_irq_wake(qcom->ss_phy_irq);
> -	}
> +	dwc3_qcom_enable_wakeup_irq(qcom->ss_phy_irq);
>  }
>  
>  static int dwc3_qcom_suspend(struct dwc3_qcom *qcom)
> -- 
> 2.7.4
>