Re: [PATCH v3 2/5] usb: dwc3: host: Add suspend_quirk for dwc3 host

Matthias Kaehlcke
2020-09-29T18:50:12Z

On Tue, Sep 29, 2020 at 04:17:29PM +0530, Sandeep Maheswaram wrote:
> Adding suspend quirk function for dwc3 host which will be called
> during xhci suspend.
> Setting hs_phy_flags, ss_phy_flags and phy mode during host suspend.
>
> Signed-off-by: Sandeep Maheswaram <sanm@codeaurora.org>
> ---
> drivers/usb/dwc3/host.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 49 insertions(+)
>
> diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
> index e195176..7f316fa 100644
> --- a/drivers/usb/dwc3/host.c
> +++ b/drivers/usb/dwc3/host.c
> @@ -11,6 +11,13 @@
> #include <linux/platform_device.h>
>
> #include "core.h"
> +#include "../host/xhci.h"
> +#include "../host/xhci-plat.h"
> +int xhci_dwc3_suspend_quirk(struct usb_hcd *hcd);
> +
> +static const struct xhci_plat_priv xhci_plat_dwc3_xhci = {
> + .suspend_quirk = xhci_dwc3_suspend_quirk,
> +};
>
> static int dwc3_host_get_irq(struct dwc3 *dwc)
> {
> @@ -115,6 +122,13 @@ int dwc3_host_init(struct dwc3 *dwc)
> }
> }
>
> + ret = platform_device_add_data(xhci, &xhci_plat_dwc3_xhci,
> + sizeof(struct xhci_plat_priv));
> + if (ret) {
> + dev_err(dwc->dev, "failed to add data to xHCI\n");
> + goto err;
> + }
> +
> ret = platform_device_add(xhci);
> if (ret) {
> dev_err(dwc->dev, "failed to register xHCI device\n");
> @@ -127,6 +141,41 @@ int dwc3_host_init(struct dwc3 *dwc)
> return ret;
> }
>
> +static void dwc3_set_phy_speed_flags(struct usb_hcd *hcd)

The main thing this function does is setting the PHY mode (see
the phy_set_mode() calls), please rename it to dwc3_set_phy_mode()
to reflect this.

> +{
> +
> + int i, num_ports;
> + u32 reg;
> + struct device *dev = hcd->self.controller;
> + struct dwc3 *dwc = dev_get_drvdata(dev->parent);
> + struct xhci_hcd *xhci_hcd = hcd_to_xhci(hcd);
> +
> + dwc->hs_phy_flags = 0;

What about 'dwc->ss_phy_flags'?

I suggested in another patch to use a local variable instead, so you
probably have to initialize it anyway or the compiler will be unhappy ;-)

> +
> + 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 * 0x04);
> + 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;

nit: add empty line to visually separate HS from SS

> + if (DEV_SUPERSPEED(reg))
> + dwc->ss_phy_flags |= PHY_MODE_USB_HOST_SS;
> + }
> + }
> + phy_set_mode(dwc->usb2_generic_phy, dwc->hs_phy_flags);
> + phy_set_mode(dwc->usb3_generic_phy, dwc->ss_phy_flags);

Check return values and return any errors?