2017-12-06 14:59:49

by Minas Harutyunyan

Subject: [PATCH] usb: dwc2: hcd: Fix host channel halt flow

According databook in Buffer and External DMA mode
non-split periodic channels can't be halted.

Signed-off-by: Minas Harutyunyan <[email protected]>
---
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);

--
2.11.0

2017-12-07 17:15:00

by Stefan Wahren

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 <[email protected]>

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);
>