Re: [PATCH 2/2] usb: xhci-mtk: Do not create shared_hcd if no USB 3.0 port available

Chunfeng Yun
2019-05-07T07:37:24Z

Hi Nicolas,
On Thu, 2019-05-02 at 12:56 +0800, Nicolas Boichat wrote:
> When the controller only supports USB 2.0, do not even create the
> USB 3.0 hcd/root hub.
>
> Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
> ---
> drivers/usb/host/xhci-mtk.c | 44 +++++++++++++++++++++++--------------
> 1 file changed, 28 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c
> index 026fe18972d3e5b..189f5dc614e6e05 100644
> --- a/drivers/usb/host/xhci-mtk.c
> +++ b/drivers/usb/host/xhci-mtk.c
> @@ -527,23 +527,28 @@ static int xhci_mtk_probe(struct platform_device *pdev)
> xhci->imod_interval = 5000;
> device_property_read_u32(dev, "imod-interval-ns", &xhci->imod_interval);
>
> - xhci->shared_hcd = usb_create_shared_hcd(driver, dev,
> + /* Only create shared_hcd when USB3.0 port is available. */
> + if (xhci->usb3_rhub.num_ports > 0) {
xhci->usb3_rhub.num_ports is not set until usb_add_hcd() is called.

> + xhci->shared_hcd = usb_create_shared_hcd(driver, dev,
> dev_name(dev), hcd);
> - if (!xhci->shared_hcd) {
> - ret = -ENOMEM;
> - goto disable_device_wakeup;
> + if (!xhci->shared_hcd) {
> + ret = -ENOMEM;
> + goto disable_device_wakeup;
> + }
> }
>
> ret = usb_add_hcd(hcd, irq, IRQF_SHARED);
> if (ret)
> goto put_usb3_hcd;
>
> - if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
> - xhci->shared_hcd->can_do_streams = 1;
> + if (xhci->usb3_rhub.num_ports > 0) {
> + if (HCC_MAX_PSA(xhci->hcc_params) >= 4)
> + xhci->shared_hcd->can_do_streams = 1;
>
> - ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
> - if (ret)
> - goto dealloc_usb2_hcd;
> + ret = usb_add_hcd(xhci->shared_hcd, irq, IRQF_SHARED);
> + if (ret)
> + goto dealloc_usb2_hcd;
> + }
>
> return 0;
>
> @@ -552,7 +557,8 @@ static int xhci_mtk_probe(struct platform_device *pdev)
>
> put_usb3_hcd:
> xhci_mtk_sch_exit(mtk);
> - usb_put_hcd(xhci->shared_hcd);
> + if (xhci->shared_hcd)
> + usb_put_hcd(xhci->shared_hcd);
>
> disable_device_wakeup:
> device_init_wakeup(dev, false);
> @@ -579,12 +585,14 @@ static int xhci_mtk_remove(struct platform_device *dev)
> struct xhci_hcd *xhci = hcd_to_xhci(hcd);
> struct usb_hcd *shared_hcd = xhci->shared_hcd;
>
> - usb_remove_hcd(shared_hcd);
> + if (shared_hcd)
> + usb_remove_hcd(shared_hcd);
> xhci->shared_hcd = NULL;
> device_init_wakeup(&dev->dev, false);
>
> usb_remove_hcd(hcd);
> - usb_put_hcd(shared_hcd);
> + if (shared_hcd)
> + usb_put_hcd(shared_hcd);
> usb_put_hcd(hcd);
> xhci_mtk_sch_exit(mtk);
> xhci_mtk_clks_disable(mtk);
> @@ -611,8 +619,10 @@ static int __maybe_unused xhci_mtk_suspend(struct device *dev)
> xhci_dbg(xhci, "%s: stop port polling\n", __func__);
> clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
> del_timer_sync(&hcd->rh_timer);
> - clear_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
> - del_timer_sync(&xhci->shared_hcd->rh_timer);
> + if (xhci->shared_hcd) {
> + clear_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
> + del_timer_sync(&xhci->shared_hcd->rh_timer);
> + }
>
> xhci_mtk_host_disable(mtk);
> xhci_mtk_clks_disable(mtk);
> @@ -631,8 +641,10 @@ static int __maybe_unused xhci_mtk_resume(struct device *dev)
> xhci_mtk_host_enable(mtk);
>
> xhci_dbg(xhci, "%s: restart port polling\n", __func__);
> - set_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
> - usb_hcd_poll_rh_status(xhci->shared_hcd);
> + if (xhci->shared_hcd) {
> + set_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
> + usb_hcd_poll_rh_status(xhci->shared_hcd);
> + }
> set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
> usb_hcd_poll_rh_status(hcd);
> return 0;