[<prev] [next>] [day] [month] [year] [list]
Message-ID: <8e14e212-c995-de21-676e-b6f8bc1c613f@i2se.com>
Date: Thu, 7 Dec 2017 18:14:44 +0100
From: Stefan Wahren <stefan.wahren@...e.com>
To: Minas Harutyunyan <Minas.Harutyunyan@...opsys.com>
Cc: John Youn <John.Youn@...opsys.com>,
Felipe Balbi <balbi@...nel.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
"linux-usb@...r.kernel.org" <linux-usb@...r.kernel.org>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] usb: dwc2: hcd: Fix host channel halt flow
Hi Minas,
Am 07.12.2017 um 18:08 schrieb Stefan Wahren:
> According databook in Buffer and External DMA mode
> non-split periodic channels can't be halted.
do you know of any consequences not having this patch applied?
>
> Signed-off-by: Minas Harutyunyan <hminas@...opsys.com>
Please add a fixes tag.
Thanks
Stefan
> ---
> drivers/usb/dwc2/hcd.c | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
> index 614bb9603def..987122497408 100644
> --- a/drivers/usb/dwc2/hcd.c
> +++ b/drivers/usb/dwc2/hcd.c
> @@ -985,6 +985,25 @@ void dwc2_hc_halt(struct dwc2_hsotg *hsotg, struct dwc2_host_chan *chan,
>
> if (dbg_hc(chan))
> dev_vdbg(hsotg->dev, "%s()\n", __func__);
> +
> + /*
> + * In buffer DMA or external DMA mode channel can't be halted
> + * for non-split periodic channels. At the end of the next
> + * uframe/frame (in the worst case), the core generates a channel
> + * halted and disables the channel automatically.
> + */
> + if ((hsotg->core_params->dma_enable > 0 &&
> + hsotg->core_params->dma_desc_enable <= 0) ||
> + hsotg->hw_params.arch == GHWCFG2_EXT_DMA_ARCH) {
> + if (!chan->do_split &&
> + (chan->ep_type == USB_ENDPOINT_XFER_ISOC ||
> + chan->ep_type == USB_ENDPOINT_XFER_INT)) {
> + dev_err(hsotg->dev, "%s() Channel can't be halted\n",
> + __func__);
> + return;
> + }
> + }
> +
> if (halt_status == DWC2_HC_XFER_NO_HALT_STATUS)
> dev_err(hsotg->dev, "!!! halt_status = %d !!!\n", halt_status);
>
Powered by blists - more mailing lists