Re: patch "usb: xhci-mtk: skip dropping bandwidth of unchecked endpoints" added to usb-linus

[Chunfeng Yun <chunfeng.yun@mediatek.com>]

Hi Greg,

   I sent out v2, add 'break' when find the ep in
xhci_mtk_drop_ep_quirk(), but no effect with the function.
Please pick up v2 if possible, sorry for inconvenience



On Mon, 2021-02-01 at 14:11 +0100, gregkh@linuxfoundation.org wrote:
> This is a note to let you know that I've just added the patch titled
> 
>     usb: xhci-mtk: skip dropping bandwidth of unchecked endpoints
> 
> to my usb git tree which can be found at
>     git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
> in the usb-linus branch.
> 
> The patch will show up in the next release of the linux-next tree
> (usually sometime within the next 24 hours during the week.)
> 
> The patch will hopefully also be merged in Linus's tree for the
> next -rc kernel release.
> 
> If you have any questions about this process, please let me know.
> 
> 
> From 54f6a8af372213a254af6609758d99f7c0b6b5ad Mon Sep 17 00:00:00 2001
> From: Chunfeng Yun <chunfeng.yun@mediatek.com>
> Date: Mon, 1 Feb 2021 13:57:44 +0800
> Subject: usb: xhci-mtk: skip dropping bandwidth of unchecked endpoints
> 
> For those unchecked endpoints, we don't allocate bandwidth for
> them, so no need free the bandwidth, otherwise will decrease
> the allocated bandwidth.
> Meanwhile use xhci_dbg() instead of dev_dbg() to print logs and
> rename bw_ep_list_new as bw_ep_chk_list.
> 
> Fixes: 1d69f9d901ef ("usb: xhci-mtk: fix unreleased bandwidth data")
> Cc: stable <stable@vger.kernel.org>
> Reviewed-and-tested-by: Ikjoon Jang <ikjn@chromium.org>
> Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> Link: https://lore.kernel.org/r/1612159064-28413-1-git-send-email-chunfeng.yun@mediatek.com
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/usb/host/xhci-mtk-sch.c | 61 ++++++++++++++++++---------------
>  drivers/usb/host/xhci-mtk.h     |  4 ++-
>  2 files changed, 36 insertions(+), 29 deletions(-)
> 
> diff --git a/drivers/usb/host/xhci-mtk-sch.c b/drivers/usb/host/xhci-mtk-sch.c
> index a313e75ff1c6..dee8a329076d 100644
> --- a/drivers/usb/host/xhci-mtk-sch.c
> +++ b/drivers/usb/host/xhci-mtk-sch.c
> @@ -200,6 +200,7 @@ static struct mu3h_sch_ep_info *create_sch_ep(struct usb_device *udev,
>  
>  	sch_ep->sch_tt = tt;
>  	sch_ep->ep = ep;
> +	INIT_LIST_HEAD(&sch_ep->endpoint);
>  	INIT_LIST_HEAD(&sch_ep->tt_endpoint);
>  
>  	return sch_ep;
> @@ -374,6 +375,7 @@ static void update_bus_bw(struct mu3h_sch_bw_info *sch_bw,
>  					sch_ep->bw_budget_table[j];
>  		}
>  	}
> +	sch_ep->allocated = used;
>  }
>  
>  static int check_sch_tt(struct usb_device *udev,
> @@ -542,6 +544,22 @@ static int check_sch_bw(struct usb_device *udev,
>  	return 0;
>  }
>  
> +static void destroy_sch_ep(struct usb_device *udev,
> +	struct mu3h_sch_bw_info *sch_bw, struct mu3h_sch_ep_info *sch_ep)
> +{
> +	/* only release ep bw check passed by check_sch_bw() */
> +	if (sch_ep->allocated)
> +		update_bus_bw(sch_bw, sch_ep, 0);
> +
> +	list_del(&sch_ep->endpoint);
> +
> +	if (sch_ep->sch_tt) {
> +		list_del(&sch_ep->tt_endpoint);
> +		drop_tt(udev);
> +	}
> +	kfree(sch_ep);
> +}
> +
>  static bool need_bw_sch(struct usb_host_endpoint *ep,
>  	enum usb_device_speed speed, int has_tt)
>  {
> @@ -584,7 +602,7 @@ int xhci_mtk_sch_init(struct xhci_hcd_mtk *mtk)
>  
>  	mtk->sch_array = sch_array;
>  
> -	INIT_LIST_HEAD(&mtk->bw_ep_list_new);
> +	INIT_LIST_HEAD(&mtk->bw_ep_chk_list);
>  
>  	return 0;
>  }
> @@ -636,29 +654,12 @@ int xhci_mtk_add_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
>  
>  	setup_sch_info(udev, ep_ctx, sch_ep);
>  
> -	list_add_tail(&sch_ep->endpoint, &mtk->bw_ep_list_new);
> +	list_add_tail(&sch_ep->endpoint, &mtk->bw_ep_chk_list);
>  
>  	return 0;
>  }
>  EXPORT_SYMBOL_GPL(xhci_mtk_add_ep_quirk);
>  
> -static void xhci_mtk_drop_ep(struct xhci_hcd_mtk *mtk, struct usb_device *udev,
> -			     struct mu3h_sch_ep_info *sch_ep)
> -{
> -	struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
> -	int bw_index = get_bw_index(xhci, udev, sch_ep->ep);
> -	struct mu3h_sch_bw_info *sch_bw = &mtk->sch_array[bw_index];
> -
> -	update_bus_bw(sch_bw, sch_ep, 0);
> -	list_del(&sch_ep->endpoint);
> -
> -	if (sch_ep->sch_tt) {
> -		list_del(&sch_ep->tt_endpoint);
> -		drop_tt(udev);
> -	}
> -	kfree(sch_ep);
> -}
> -
>  void xhci_mtk_drop_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
>  		struct usb_host_endpoint *ep)
>  {
> @@ -688,9 +689,8 @@ void xhci_mtk_drop_ep_quirk(struct usb_hcd *hcd, struct usb_device *udev,
>  	sch_bw = &sch_array[bw_index];
>  
>  	list_for_each_entry_safe(sch_ep, tmp, &sch_bw->bw_ep_list, endpoint) {
> -		if (sch_ep->ep == ep) {
> -			xhci_mtk_drop_ep(mtk, udev, sch_ep);
> -		}
> +		if (sch_ep->ep == ep)
> +			destroy_sch_ep(udev, sch_bw, sch_ep);
>  	}
>  }
>  EXPORT_SYMBOL_GPL(xhci_mtk_drop_ep_quirk);
> @@ -704,9 +704,9 @@ int xhci_mtk_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
>  	struct mu3h_sch_ep_info *sch_ep, *tmp;
>  	int bw_index, ret;
>  
> -	dev_dbg(&udev->dev, "%s\n", __func__);
> +	xhci_dbg(xhci, "%s() udev %s\n", __func__, dev_name(&udev->dev));
>  
> -	list_for_each_entry(sch_ep, &mtk->bw_ep_list_new, endpoint) {
> +	list_for_each_entry(sch_ep, &mtk->bw_ep_chk_list, endpoint) {
>  		bw_index = get_bw_index(xhci, udev, sch_ep->ep);
>  		sch_bw = &mtk->sch_array[bw_index];
>  
> @@ -717,7 +717,7 @@ int xhci_mtk_check_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
>  		}
>  	}
>  
> -	list_for_each_entry_safe(sch_ep, tmp, &mtk->bw_ep_list_new, endpoint) {
> +	list_for_each_entry_safe(sch_ep, tmp, &mtk->bw_ep_chk_list, endpoint) {
>  		struct xhci_ep_ctx *ep_ctx;
>  		struct usb_host_endpoint *ep = sch_ep->ep;
>  		unsigned int ep_index = xhci_get_endpoint_index(&ep->desc);
> @@ -746,12 +746,17 @@ EXPORT_SYMBOL_GPL(xhci_mtk_check_bandwidth);
>  void xhci_mtk_reset_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
>  {
>  	struct xhci_hcd_mtk *mtk = hcd_to_mtk(hcd);
> +	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
> +	struct mu3h_sch_bw_info *sch_bw;
>  	struct mu3h_sch_ep_info *sch_ep, *tmp;
> +	int bw_index;
>  
> -	dev_dbg(&udev->dev, "%s\n", __func__);
> +	xhci_dbg(xhci, "%s() udev %s\n", __func__, dev_name(&udev->dev));
>  
> -	list_for_each_entry_safe(sch_ep, tmp, &mtk->bw_ep_list_new, endpoint) {
> -		xhci_mtk_drop_ep(mtk, udev, sch_ep);
> +	list_for_each_entry_safe(sch_ep, tmp, &mtk->bw_ep_chk_list, endpoint) {
> +		bw_index = get_bw_index(xhci, udev, sch_ep->ep);
> +		sch_bw = &mtk->sch_array[bw_index];
> +		destroy_sch_ep(udev, sch_bw, sch_ep);
>  	}
>  
>  	xhci_reset_bandwidth(hcd, udev);
> diff --git a/drivers/usb/host/xhci-mtk.h b/drivers/usb/host/xhci-mtk.h
> index 577f431c5c93..cbb09dfea62e 100644
> --- a/drivers/usb/host/xhci-mtk.h
> +++ b/drivers/usb/host/xhci-mtk.h
> @@ -59,6 +59,7 @@ struct mu3h_sch_bw_info {
>   * @ep_type: endpoint type
>   * @maxpkt: max packet size of endpoint
>   * @ep: address of usb_host_endpoint struct
> + * @allocated: the bandwidth is aready allocated from bus_bw
>   * @offset: which uframe of the interval that transfer should be
>   *		scheduled first time within the interval
>   * @repeat: the time gap between two uframes that transfers are
> @@ -86,6 +87,7 @@ struct mu3h_sch_ep_info {
>  	u32 ep_type;
>  	u32 maxpkt;
>  	void *ep;
> +	bool allocated;
>  	/*
>  	 * mtk xHCI scheduling information put into reserved DWs
>  	 * in ep context
> @@ -130,8 +132,8 @@ struct mu3c_ippc_regs {
>  struct xhci_hcd_mtk {
>  	struct device *dev;
>  	struct usb_hcd *hcd;
> -	struct list_head bw_ep_list_new;
>  	struct mu3h_sch_bw_info *sch_array;
> +	struct list_head bw_ep_chk_list;
>  	struct mu3c_ippc_regs __iomem *ippc_regs;
>  	bool has_ippc;
>  	int num_u2_ports;