diff mbox

[v2] usb: dwc3: gadget: wait for End Transfer to complete

Message ID b49c43a1580c3c9233a7d5da520ca30405342f7b.1477979405.git.baolin.wang@linaro.org
State New
Headers show

Commit Message

(Exiting) Baolin Wang Nov. 1, 2016, 5:51 a.m. UTC 
Instead of just delaying for 100us, we should
actually wait for End Transfer Command Complete
interrupt before moving on. Note that this should
only be done if we're dealing with one of the core
revisions that actually require the interrupt before
moving on.

[ felipe.balbi@linux.intel.com: minor improvements ]

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>

---
Changes since v1:
 - Move the suspend checking to right place to avoid checking twice.
---
 drivers/usb/dwc3/core.h   |    8 ++++++++
 drivers/usb/dwc3/gadget.c |   49 +++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 53 insertions(+), 4 deletions(-)

-- 
1.7.9.5

Comments

(Exiting) Baolin Wang Nov. 1, 2016, 11:46 a.m. UTC | #1 
Hi,

On 1 November 2016 at 19:36, Felipe Balbi <balbi@kernel.org> wrote:
>

> Hi,

>

> Baolin Wang <baolin.wang@linaro.org> writes:

>> Hi,

>>

>> On 1 November 2016 at 19:01, Felipe Balbi <balbi@kernel.org> wrote:

>>>

>>> Hi,

>>>

>>> Baolin Wang <baolin.wang@linaro.org> writes:

>>>> Changes since v1:

>>>>  - Move the suspend checking to right place to avoid checking twice.

>>>

>>> there is still one problem

>>>

>>>> @@ -1736,12 +1739,38 @@ static int dwc3_gadget_stop(struct usb_gadget *g)

>>>>  {

>>>>       struct dwc3             *dwc = gadget_to_dwc(g);

>>>>       unsigned long           flags;

>>>> +     int                     epnum;

>>>>

>>>>       spin_lock_irqsave(&dwc->lock, flags);

>>>>       __dwc3_gadget_stop(dwc);

>>>

>>> this tries to access registers. If __dwc3_gadget_stop() runs while

>>> clocks are gated, we will get Data Abort exception.

>>

>> We have suspend checking in __dwc3_gadget_stop(), thus it will not

>> access registers if clocks are disabled.

>>

>>>

>>> How about this version, instead?

>>

>> I think it is OK except we missed set 'dwc->gadget_driver = NULL'.

>

> argh. Man, next time we meet in a conference, I owe you a beer :-)


Okay:) Now it looks good to me. Thanks.

>

> 8<------------------------------------------------------------------------------

> From 06a204f1c2276ca1ffe68d8d59ef2e2ead337bba Mon Sep 17 00:00:00 2001

> From: Baolin Wang <baolin.wang@linaro.org>

> Date: Mon, 31 Oct 2016 19:38:36 +0800

> Subject: [PATCH] usb: dwc3: gadget: wait for End Transfer to complete

>

> Instead of just delaying for 100us, we should

> actually wait for End Transfer Command Complete

> interrupt before moving on. Note that this should

> only be done if we're dealing with one of the core

> revisions that actually require the interrupt before

> moving on.

>

> [ felipe.balbi@linux.intel.com: minor improvements ]

>

> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>

> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

> ---

>  drivers/usb/dwc3/core.h   |  8 ++++++++

>  drivers/usb/dwc3/gadget.c | 49 +++++++++++++++++++++++++++++++++++++++--------

>  2 files changed, 49 insertions(+), 8 deletions(-)

>

> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h

> index 5fc437021ac7..c2b86856e85d 100644

> --- a/drivers/usb/dwc3/core.h

> +++ b/drivers/usb/dwc3/core.h

> @@ -26,6 +26,7 @@

>  #include <linux/dma-mapping.h>

>  #include <linux/mm.h>

>  #include <linux/debugfs.h>

> +#include <linux/wait.h>

>

>  #include <linux/usb/ch9.h>

>  #include <linux/usb/gadget.h>

> @@ -505,6 +506,7 @@ struct dwc3_event_buffer {

>   * @endpoint: usb endpoint

>   * @pending_list: list of pending requests for this endpoint

>   * @started_list: list of started requests on this endpoint

> + * @wait_end_transfer: wait_queue_head_t for waiting on End Transfer complete

>   * @lock: spinlock for endpoint request queue traversal

>   * @regs: pointer to first endpoint register

>   * @trb_pool: array of transaction buffers

> @@ -530,6 +532,8 @@ struct dwc3_ep {

>         struct list_head        pending_list;

>         struct list_head        started_list;

>

> +       wait_queue_head_t       wait_end_transfer;

> +

>         spinlock_t              lock;

>         void __iomem            *regs;

>

> @@ -546,6 +550,7 @@ struct dwc3_ep {

>  #define DWC3_EP_BUSY           (1 << 4)

>  #define DWC3_EP_PENDING_REQUEST        (1 << 5)

>  #define DWC3_EP_MISSED_ISOC    (1 << 6)

> +#define DWC3_EP_END_TRANSFER_PENDING   (1 << 7)

>

>         /* This last one is specific to EP0 */

>  #define DWC3_EP0_DIR_IN                (1 << 31)

> @@ -1050,6 +1055,9 @@ struct dwc3_event_depevt {

>  #define DEPEVT_TRANSFER_BUS_EXPIRY     2

>

>         u32     parameters:16;

> +

> +/* For Command Complete Events */

> +#define DEPEVT_PARAMETER_CMD(n)        (((n) & (0xf << 8)) >> 8)

>  } __packed;

>

>  /**

> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c

> index 4743e53cc295..64d01ff8c119 100644

> --- a/drivers/usb/dwc3/gadget.c

> +++ b/drivers/usb/dwc3/gadget.c

> @@ -593,11 +593,14 @@ static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,

>                 dep->comp_desc = comp_desc;

>                 dep->type = usb_endpoint_type(desc);

>                 dep->flags |= DWC3_EP_ENABLED;

> +               dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;

>

>                 reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);

>                 reg |= DWC3_DALEPENA_EP(dep->number);

>                 dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);

>

> +               init_waitqueue_head(&dep->wait_end_transfer);

> +

>                 if (usb_endpoint_xfer_control(desc))

>                         return 0;

>

> @@ -699,7 +702,7 @@ static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)

>         dep->endpoint.desc = NULL;

>         dep->comp_desc = NULL;

>         dep->type = 0;

> -       dep->flags = 0;

> +       dep->flags &= DWC3_EP_END_TRANSFER_PENDING;

>

>         return 0;

>  }

> @@ -1783,9 +1786,6 @@ static int dwc3_gadget_start(struct usb_gadget *g,

>

>  static void __dwc3_gadget_stop(struct dwc3 *dwc)

>  {

> -       if (pm_runtime_suspended(dwc->dev))

> -               return;

> -

>         dwc3_gadget_disable_irq(dwc);

>         __dwc3_gadget_ep_disable(dwc->eps[0]);

>         __dwc3_gadget_ep_disable(dwc->eps[1]);

> @@ -1795,9 +1795,30 @@ static int dwc3_gadget_stop(struct usb_gadget *g)

>  {

>         struct dwc3             *dwc = gadget_to_dwc(g);

>         unsigned long           flags;

> +       int                     epnum;

>

>         spin_lock_irqsave(&dwc->lock, flags);

> +

> +       if (pm_runtime_suspended(dwc->dev))

> +               goto out;

> +

>         __dwc3_gadget_stop(dwc);

> +

> +       for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {

> +               struct dwc3_ep  *dep = dwc->eps[epnum];

> +

> +               if (!dep)

> +                       continue;

> +

> +               if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))

> +                       continue;

> +

> +               wait_event_lock_irq(dep->wait_end_transfer,

> +                                   !(dep->flags & DWC3_EP_END_TRANSFER_PENDING),

> +                                   dwc->lock);

> +       }

> +

> +out:

>         dwc->gadget_driver      = NULL;

>         spin_unlock_irqrestore(&dwc->lock, flags);

>

> @@ -2171,10 +2192,12 @@ static void dwc3_endpoint_interrupt(struct dwc3 *dwc,

>  {

>         struct dwc3_ep          *dep;

>         u8                      epnum = event->endpoint_number;

> +       u8                      cmd;

>

>         dep = dwc->eps[epnum];

>

> -       if (!(dep->flags & DWC3_EP_ENABLED))

> +       if (!(dep->flags & DWC3_EP_ENABLED) &&

> +           !(dep->flags & DWC3_EP_END_TRANSFER_PENDING))

>                 return;

>

>         if (epnum == 0 || epnum == 1) {

> @@ -2215,8 +2238,15 @@ static void dwc3_endpoint_interrupt(struct dwc3 *dwc,

>                         return;

>                 }

>                 break;

> -       case DWC3_DEPEVT_RXTXFIFOEVT:

>         case DWC3_DEPEVT_EPCMDCMPLT:

> +               cmd = DEPEVT_PARAMETER_CMD(event->parameters);

> +

> +               if (cmd == DWC3_DEPCMD_ENDTRANSFER) {

> +                       dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;

> +                       wake_up(&dep->wait_end_transfer);

> +               }

> +               break;

> +       case DWC3_DEPEVT_RXTXFIFOEVT:

>                 break;

>         }

>  }

> @@ -2269,7 +2299,8 @@ static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)

>

>         dep = dwc->eps[epnum];

>

> -       if (!dep->resource_index)

> +       if ((dep->flags & DWC3_EP_END_TRANSFER_PENDING) ||

> +           !dep->resource_index)

>                 return;

>

>         /*

> @@ -2313,8 +2344,10 @@ static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)

>         dep->resource_index = 0;

>         dep->flags &= ~DWC3_EP_BUSY;

>

> -       if (dwc3_is_usb31(dwc) || dwc->revision < DWC3_REVISION_310A)

> +       if (dwc3_is_usb31(dwc) || dwc->revision < DWC3_REVISION_310A) {

> +               dep->flags |= DWC3_EP_END_TRANSFER_PENDING;

>                 udelay(100);

> +       }

>  }

>

>  static void dwc3_clear_stall_all_ep(struct dwc3 *dwc)

> --

> 2.10.1

>

>

>

> --

> balbi




-- 
Baolin.wang
Best Regards
diff mbox

Patch

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 23765a1..c5fd862 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -26,6 +26,7 @@ 
 #include <linux/dma-mapping.h>
 #include <linux/mm.h>
 #include <linux/debugfs.h>
+#include <linux/wait.h>
 
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
@@ -496,6 +497,7 @@  struct dwc3_event_buffer {
  * @endpoint: usb endpoint
  * @pending_list: list of pending requests for this endpoint
  * @started_list: list of started requests on this endpoint
+ * @wait_end_transfer: wait_queue_head_t for waiting on End Transfer complete
  * @lock: spinlock for endpoint request queue traversal
  * @regs: pointer to first endpoint register
  * @trb_pool: array of transaction buffers
@@ -521,6 +523,8 @@  struct dwc3_ep {
 	struct list_head	pending_list;
 	struct list_head	started_list;
 
+	wait_queue_head_t	wait_end_transfer;
+
 	spinlock_t		lock;
 	void __iomem		*regs;
 
@@ -537,6 +541,7 @@  struct dwc3_ep {
 #define DWC3_EP_BUSY		(1 << 4)
 #define DWC3_EP_PENDING_REQUEST	(1 << 5)
 #define DWC3_EP_MISSED_ISOC	(1 << 6)
+#define DWC3_EP_END_TRANSFER_PENDING	(1 << 7)
 
 	/* This last one is specific to EP0 */
 #define DWC3_EP0_DIR_IN		(1 << 31)
@@ -1044,6 +1049,9 @@  struct dwc3_event_depevt {
 #define DEPEVT_TRANSFER_BUS_EXPIRY	2
 
 	u32	parameters:16;
+
+/* For Command Complete Events */
+#define DEPEVT_PARAMETER_CMD(n)	(((n) & (0xf << 8)) >> 8)
 } __packed;
 
 /**
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 3722c90..e248bd3 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -570,11 +570,14 @@  static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
 		dep->comp_desc = comp_desc;
 		dep->type = usb_endpoint_type(desc);
 		dep->flags |= DWC3_EP_ENABLED;
+		dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
 
 		reg = dwc3_readl(dwc->regs, DWC3_DALEPENA);
 		reg |= DWC3_DALEPENA_EP(dep->number);
 		dwc3_writel(dwc->regs, DWC3_DALEPENA, reg);
 
+		init_waitqueue_head(&dep->wait_end_transfer);
+
 		if (usb_endpoint_xfer_control(desc))
 			return 0;
 
@@ -647,7 +650,7 @@  static int __dwc3_gadget_ep_disable(struct dwc3_ep *dep)
 	dep->endpoint.desc = NULL;
 	dep->comp_desc = NULL;
 	dep->type = 0;
-	dep->flags = 0;
+	dep->flags &= DWC3_EP_END_TRANSFER_PENDING;
 
 	return 0;
 }
@@ -1736,12 +1739,38 @@  static int dwc3_gadget_stop(struct usb_gadget *g)
 {
 	struct dwc3		*dwc = gadget_to_dwc(g);
 	unsigned long		flags;
+	int			epnum;
 
 	spin_lock_irqsave(&dwc->lock, flags);
 	__dwc3_gadget_stop(dwc);
 	dwc->gadget_driver	= NULL;
+
+	/*
+	 * If the dwc3 core has been in suspend state, we will never get
+	 * the command complete event, thus ignore.
+	 */
+	if (pm_runtime_suspended(dwc->dev)) {
+		spin_unlock_irqrestore(&dwc->lock, flags);
+		goto out;
+	}
+
+	for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) {
+		struct dwc3_ep  *dep = dwc->eps[epnum];
+
+		if (!dep)
+			continue;
+
+		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
+			continue;
+
+		wait_event_lock_irq(dep->wait_end_transfer,
+				    !(dep->flags & DWC3_EP_END_TRANSFER_PENDING),
+				    dwc->lock);
+	}
+
 	spin_unlock_irqrestore(&dwc->lock, flags);
 
+out:
 	free_irq(dwc->irq_gadget, dwc->ev_buf);
 
 	return 0;
@@ -2105,10 +2134,12 @@  static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
 {
 	struct dwc3_ep		*dep;
 	u8			epnum = event->endpoint_number;
+	u8			cmd;
 
 	dep = dwc->eps[epnum];
 
-	if (!(dep->flags & DWC3_EP_ENABLED))
+	if (!(dep->flags & DWC3_EP_ENABLED) &&
+	    !(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
 		return;
 
 	if (epnum == 0 || epnum == 1) {
@@ -2180,6 +2211,13 @@  static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
 		dwc3_trace(trace_dwc3_gadget, "%s FIFO Overrun", dep->name);
 		break;
 	case DWC3_DEPEVT_EPCMDCMPLT:
+		cmd = DEPEVT_PARAMETER_CMD(event->parameters);
+
+		if (cmd == DWC3_DEPCMD_ENDTRANSFER) {
+			dep->flags &= ~DWC3_EP_END_TRANSFER_PENDING;
+			wake_up(&dep->wait_end_transfer);
+		}
+
 		dwc3_trace(trace_dwc3_gadget, "Endpoint Command Complete");
 		break;
 	}
@@ -2233,7 +2271,8 @@  static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
 
 	dep = dwc->eps[epnum];
 
-	if (!dep->resource_index)
+	if ((dep->flags & DWC3_EP_END_TRANSFER_PENDING) ||
+	    !dep->resource_index)
 		return;
 
 	/*
@@ -2277,8 +2316,10 @@  static void dwc3_stop_active_transfer(struct dwc3 *dwc, u32 epnum, bool force)
 	dep->resource_index = 0;
 	dep->flags &= ~DWC3_EP_BUSY;
 
-	if (dwc3_is_usb31(dwc) || dwc->revision < DWC3_REVISION_310A)
+	if (dwc3_is_usb31(dwc) || dwc->revision < DWC3_REVISION_310A) {
+		dep->flags |= DWC3_EP_END_TRANSFER_PENDING;
 		udelay(100);
+	}
 }
 
 static void dwc3_stop_active_transfers(struct dwc3 *dwc)