linux-kernel - Re: [PATCH 2/2] usb: dwc3: Host wake up support from system suspend

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: <874kp9pmvf.fsf@kernel.org>
Date:   Tue, 11 Aug 2020 12:12:20 +0300
From:   Felipe Balbi <balbi@...nel.org>
To:     Sandeep Maheswaram <sanm@...eaurora.org>,
        Andy Gross <agross@...nel.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Stephen Boyd <swboyd@...omium.org>,
        Doug Anderson <dianders@...omium.org>,
        Matthias Kaehlcke <mka@...omium.org>,
        Michael Turquette <mturquette@...libre.com>
Cc:     linux-arm-msm@...r.kernel.org, linux-usb@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        Manu Gautam <mgautam@...eaurora.org>,
        linux-clk@...r.kernel.org, Taniya Das <tdas@...eaurora.org>,
        Sandeep Maheswaram <sanm@...eaurora.org>
Subject: Re: [PATCH 2/2] usb: dwc3: Host wake up support from system suspend

Sandeep Maheswaram <sanm@...eaurora.org> writes:

> Avoiding phy powerdown in host mode so that it can be wake up by devices.
> Set usb controller wakeup capable when wakeup capable devices are
> connected to the host.
>
> Signed-off-by: Sandeep Maheswaram <sanm@...eaurora.org>
> ---
>  drivers/usb/dwc3/core.c      | 47 ++++++++++++++++++++++++++-----
>  drivers/usb/dwc3/core.h      |  1 +
>  drivers/usb/dwc3/dwc3-qcom.c | 66 +++++++++++++++++++++++++++++++++-----------
>  3 files changed, 91 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 25c686a7..8370350 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -31,15 +31,19 @@
>  #include <linux/usb/gadget.h>
>  #include <linux/usb/of.h>
>  #include <linux/usb/otg.h>
> +#include <linux/usb/hcd.h>
>  
>  #include "core.h"
>  #include "gadget.h"
>  #include "io.h"
>  
>  #include "debug.h"
> +#include "../host/xhci.h"

nope

>  #define DWC3_DEFAULT_AUTOSUSPEND_DELAY	5000 /* ms */
>  
> +bool need_phy_for_wakeup;

nope

> +
>  /**
>   * dwc3_get_dr_mode - Validates and sets dr_mode
>   * @dwc: pointer to our context structure
> @@ -1627,10 +1631,36 @@ static int dwc3_core_init_for_resume(struct dwc3 *dwc)
>  	return ret;
>  }
>  
> +static void dwc3_set_phy_speed_flags(struct dwc3 *dwc)
> +{
> +
> +	int i, num_ports;
> +	u32 reg;
> +	struct usb_hcd	*hcd = platform_get_drvdata(dwc->xhci);
> +	struct xhci_hcd	*xhci_hcd = hcd_to_xhci(hcd);
> +
> +	dwc->hs_phy_flags &= ~(PHY_MODE_USB_HOST_HS | PHY_MODE_USB_HOST_LS);
> +
> +	reg = readl(&xhci_hcd->cap_regs->hcs_params1);
> +
> +	num_ports = HCS_MAX_PORTS(reg);
> +	for (i = 0; i < num_ports; i++) {
> +		reg = readl(&xhci_hcd->op_regs->port_status_base + i*0x10);
> +		if (reg & PORT_PE) {
> +			if (DEV_HIGHSPEED(reg) || DEV_FULLSPEED(reg))
> +				dwc->hs_phy_flags |= PHY_MODE_USB_HOST_HS;
> +			else if (DEV_LOWSPEED(reg))
> +				dwc->hs_phy_flags |= PHY_MODE_USB_HOST_LS;
> +		}
> +	}
> +	phy_set_mode(dwc->usb2_generic_phy, dwc->hs_phy_flags);

XHCI already supports PHY framework, no?

>  static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>  {
>  	unsigned long	flags;
>  	u32 reg;
> +	struct usb_hcd  *hcd = platform_get_drvdata(dwc->xhci);
>  
>  	switch (dwc->current_dr_role) {
>  	case DWC3_GCTL_PRTCAP_DEVICE:
> @@ -1643,9 +1673,10 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>  		dwc3_core_exit(dwc);
>  		break;
>  	case DWC3_GCTL_PRTCAP_HOST:
> +		dwc3_set_phy_speed_flags(dwc);
>  		if (!PMSG_IS_AUTO(msg)) {
> -			dwc3_core_exit(dwc);
> -			break;
> +			if (usb_wakeup_enabled_descendants(hcd->self.root_hub))
> +				need_phy_for_wakeup = true;

should be done in xhci-plat

> @@ -1705,11 +1736,13 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
>  		break;
>  	case DWC3_GCTL_PRTCAP_HOST:
>  		if (!PMSG_IS_AUTO(msg)) {
> -			ret = dwc3_core_init_for_resume(dwc);
> -			if (ret)
> -				return ret;
> -			dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
> -			break;
> +			if (!need_phy_for_wakeup) {
> +				ret = dwc3_core_init_for_resume(dwc);
> +				if (ret)
> +					return ret;
> +				dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
> +				break;

why?

-- 
balbi

Download attachment "signature.asc" of type "application/pgp-signature" (833 bytes)