[v2] usb: dwc3: add tracepoints to aid debugging

Message ID 20140822204655.GJ27616@saruman.home
State New
Headers show

Commit Message

Felipe Balbi Aug. 22, 2014, 8:46 p.m.
Hi,

On Tue, Aug 19, 2014 at 11:36:05PM +0000, Paul Zimmerman wrote:
> > From: Felipe Balbi [mailto:balbi@ti.com]
> > Sent: Tuesday, August 19, 2014 3:02 PM
> > 
> > I didn't have time to test this yet (other than build testing), but how
> > does this one look ? Now we will print cute little strings for all
> > events and we still have proper link state tracking.
> > 
> > 8<---------------------------------------------------------------------
> > 
> > From 513ba489d66ff81eca056b41fda0cc965e6fe3ed Mon Sep 17 00:00:00 2001
> > From: Felipe Balbi <balbi@ti.com>
> > Date: Wed, 30 Apr 2014 17:45:10 -0500
> > Subject: [PATCH] usb: dwc3: add tracepoints to aid debugging
> > 
> > When we're debugging hard-to-reproduce and time-sensitive
> > use cases, printk() poses too much overhead. That's when
> > the kernel's tracing infrastructure comes into play.
> > 
> > This patch implements a few initial tracepoints for the
> > dwc3 driver. More traces can be added as necessary in order
> > to ease the task of debugging dwc3.
> > 
> > Signed-off-by: Felipe Balbi <balbi@ti.com>
> > ---
> >  drivers/usb/dwc3/Makefile |   5 +-
> >  drivers/usb/dwc3/core.h   |   2 +
> >  drivers/usb/dwc3/debug.c  |  73 ++++++++++++++++++++++++++
> >  drivers/usb/dwc3/debug.h  |   5 ++
> >  drivers/usb/dwc3/ep0.c    |   2 +
> >  drivers/usb/dwc3/gadget.c |  27 +++++-----
> >  drivers/usb/dwc3/io.h     |  30 +++++++++--
> >  drivers/usb/dwc3/trace.c  |  19 +++++++
> >  drivers/usb/dwc3/trace.h  | 128 ++++++++++++++++++++++++++++++++++++++++++++++
> >  9 files changed, 272 insertions(+), 19 deletions(-)
> >  create mode 100644 drivers/usb/dwc3/debug.c
> >  create mode 100644 drivers/usb/dwc3/trace.c
> >  create mode 100644 drivers/usb/dwc3/trace.h
> > 
> > diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> > index 10ac3e7..7793e6c 100644
> > --- a/drivers/usb/dwc3/Makefile
> > +++ b/drivers/usb/dwc3/Makefile
> > @@ -1,9 +1,12 @@
> > +# define_trace.h needs to know how to find our header
> > +CFLAGS_trace.o				:= -I$(src)
> > +
> >  ccflags-$(CONFIG_USB_DWC3_DEBUG)	:= -DDEBUG
> >  ccflags-$(CONFIG_USB_DWC3_VERBOSE)	+= -DVERBOSE_DEBUG
> > 
> >  obj-$(CONFIG_USB_DWC3)			+= dwc3.o
> > 
> > -dwc3-y					:= core.o
> > +dwc3-y					:= core.o debug.o trace.o
> > 
> >  ifneq ($(filter y,$(CONFIG_USB_DWC3_HOST) $(CONFIG_USB_DWC3_DUAL_ROLE)),)
> >  	dwc3-y				+= host.o
> > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > index 48fb264..dbdad87 100644
> > --- a/drivers/usb/dwc3/core.h
> > +++ b/drivers/usb/dwc3/core.h
> > @@ -33,6 +33,8 @@
> > 
> >  #include <linux/phy/phy.h>
> > 
> > +#define DWC3_MSG_MAX	500
> > +
> >  /* Global constants */
> >  #define DWC3_EP0_BOUNCE_SIZE	512
> >  #define DWC3_ENDPOINTS_NUM	32
> > diff --git a/drivers/usb/dwc3/debug.c b/drivers/usb/dwc3/debug.c
> > new file mode 100644
> > index 0000000..6e109ce
> > --- /dev/null
> > +++ b/drivers/usb/dwc3/debug.c
> > @@ -0,0 +1,73 @@
> > +/**
> > + * debug.c - DesignWare USB3 DRD Controller Debug/Trace Support
> > + *
> > + * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
> > + *
> > + * Author: Felipe Balbi <balbi@ti.com>
> > + *
> > + * This program is free software: you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2  of
> > + * the License as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > + * GNU General Public License for more details.
> > + */
> > +
> > +#include "core.h"
> > +#include "debug.h"
> > +
> > +static char event_str[DWC3_MSG_MAX];
> > +
> > +static void dwc3_endpoint_event_str(struct dwc3 *dwc,
> > +		const struct dwc3_event_depevt *event)
> > +{
> > +	struct dwc3_ep *dep = dwc->eps[event->endpoint_number];
> > +
> > +	snprintf(event_str, DWC3_MSG_MAX, "%s %s", dep->name,
> > +			dwc3_ep_event_string(event->endpoint_event));
> 
> Maybe you should also include the raw event data in the trace? Some
> of the other bits in the event besides the event number can tell you
> useful things while debugging.

I changed this to print only the raw event code. It's not that difficult
to decode by hand anyways and makes the code a lot simpler.

We can add decoding later if it really becomes annoying.

In any case here's another version, I also changed a few things in ep0,
there are no more dev_{v,}dbg inside ep0.c, this is so that we avoid
high overhead while debugging ep0 (which can be finicky at times).

Anyway, please give it another round of review. And as always, if
there's anything we might wanna add, please speak up :-)

8<--------------------------------------------------------------------

From b38435444c882a94b011e28da0f094ce98aeee59 Mon Sep 17 00:00:00 2001
From: Felipe Balbi <balbi@ti.com>
Date: Wed, 30 Apr 2014 17:45:10 -0500
Subject: [PATCH] usb: dwc3: add tracepoints to aid debugging

When we're debugging hard-to-reproduce and time-sensitive
use cases, printk() poses too much overhead. That's when
the kernel's tracing infrastructure comes into play.

This patch implements a few initial tracepoints for the
dwc3 driver. More traces can be added as necessary in order
to ease the task of debugging dwc3.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/usb/dwc3/Makefile |   5 +-
 drivers/usb/dwc3/core.h   |   2 +
 drivers/usb/dwc3/debug.c  |  33 +++++++++++
 drivers/usb/dwc3/debug.h  |   3 +
 drivers/usb/dwc3/ep0.c    |  65 ++++++++++++---------
 drivers/usb/dwc3/gadget.c |  24 +++-----
 drivers/usb/dwc3/io.h     |  30 +++++++++-
 drivers/usb/dwc3/trace.c  |  19 ++++++
 drivers/usb/dwc3/trace.h  | 143 ++++++++++++++++++++++++++++++++++++++++++++++
 9 files changed, 277 insertions(+), 47 deletions(-)
 create mode 100644 drivers/usb/dwc3/debug.c
 create mode 100644 drivers/usb/dwc3/trace.c
 create mode 100644 drivers/usb/dwc3/trace.h

Comments

Paul Zimmerman Aug. 22, 2014, 9:26 p.m. | #1
> From: Felipe Balbi [mailto:balbi@ti.com]
> Sent: Friday, August 22, 2014 1:47 PM
> 
> On Tue, Aug 19, 2014 at 11:36:05PM +0000, Paul Zimmerman wrote:
> 
> > From: Felipe Balbi <balbi@ti.com>
> > Date: Wed, 30 Apr 2014 17:45:10 -0500

> > > diff --git a/drivers/usb/dwc3/debug.c b/drivers/usb/dwc3/debug.c
> > > new file mode 100644
> > > index 0000000..6e109ce
> > > --- /dev/null
> > > +++ b/drivers/usb/dwc3/debug.c
> > > @@ -0,0 +1,73 @@
> > > +/**
> > > + * debug.c - DesignWare USB3 DRD Controller Debug/Trace Support
> > > + *
> > > + * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
> > > + *
> > > + * Author: Felipe Balbi <balbi@ti.com>
> > > + *
> > > + * This program is free software: you can redistribute it and/or modify
> > > + * it under the terms of the GNU General Public License version 2  of
> > > + * the License as published by the Free Software Foundation.
> > > + *
> > > + * This program is distributed in the hope that it will be useful,
> > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > > + * GNU General Public License for more details.
> > > + */
> > > +
> > > +#include "core.h"
> > > +#include "debug.h"
> > > +
> > > +static char event_str[DWC3_MSG_MAX];
> > > +
> > > +static void dwc3_endpoint_event_str(struct dwc3 *dwc,
> > > +		const struct dwc3_event_depevt *event)
> > > +{
> > > +	struct dwc3_ep *dep = dwc->eps[event->endpoint_number];
> > > +
> > > +	snprintf(event_str, DWC3_MSG_MAX, "%s %s", dep->name,
> > > +			dwc3_ep_event_string(event->endpoint_event));
> >
> > Maybe you should also include the raw event data in the trace? Some
> > of the other bits in the event besides the event number can tell you
> > useful things while debugging.
> 
> I changed this to print only the raw event code. It's not that difficult
> to decode by hand anyways and makes the code a lot simpler.
> 
> We can add decoding later if it really becomes annoying.
> 
> In any case here's another version, I also changed a few things in ep0,
> there are no more dev_{v,}dbg inside ep0.c, this is so that we avoid
> high overhead while debugging ep0 (which can be finicky at times).
> 
> Anyway, please give it another round of review. And as always, if
> there's anything we might wanna add, please speak up :-)
> 
> 8<--------------------------------------------------------------------
> 
> From b38435444c882a94b011e28da0f094ce98aeee59 Mon Sep 17 00:00:00 2001
> From: Felipe Balbi <balbi@ti.com>
> Date: Wed, 30 Apr 2014 17:45:10 -0500
> Subject: [PATCH] usb: dwc3: add tracepoints to aid debugging
> 
> When we're debugging hard-to-reproduce and time-sensitive
> use cases, printk() poses too much overhead. That's when
> the kernel's tracing infrastructure comes into play.
> 
> This patch implements a few initial tracepoints for the
> dwc3 driver. More traces can be added as necessary in order
> to ease the task of debugging dwc3.
> 
> Signed-off-by: Felipe Balbi <balbi@ti.com>
> ---
>  drivers/usb/dwc3/Makefile |   5 +-
>  drivers/usb/dwc3/core.h   |   2 +
>  drivers/usb/dwc3/debug.c  |  33 +++++++++++
>  drivers/usb/dwc3/debug.h  |   3 +
>  drivers/usb/dwc3/ep0.c    |  65 ++++++++++++---------
>  drivers/usb/dwc3/gadget.c |  24 +++-----
>  drivers/usb/dwc3/io.h     |  30 +++++++++-
>  drivers/usb/dwc3/trace.c  |  19 ++++++
>  drivers/usb/dwc3/trace.h  | 143 ++++++++++++++++++++++++++++++++++++++++++++++
>  9 files changed, 277 insertions(+), 47 deletions(-)
>  create mode 100644 drivers/usb/dwc3/debug.c
>  create mode 100644 drivers/usb/dwc3/trace.c
>  create mode 100644 drivers/usb/dwc3/trace.h
> 
> diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> index 10ac3e7..7793e6c 100644
> --- a/drivers/usb/dwc3/Makefile
> +++ b/drivers/usb/dwc3/Makefile
> @@ -1,9 +1,12 @@
> +# define_trace.h needs to know how to find our header
> +CFLAGS_trace.o				:= -I$(src)
> +
>  ccflags-$(CONFIG_USB_DWC3_DEBUG)	:= -DDEBUG
>  ccflags-$(CONFIG_USB_DWC3_VERBOSE)	+= -DVERBOSE_DEBUG
> 
>  obj-$(CONFIG_USB_DWC3)			+= dwc3.o
> 
> -dwc3-y					:= core.o
> +dwc3-y					:= core.o debug.o trace.o
> 
>  ifneq ($(filter y,$(CONFIG_USB_DWC3_HOST) $(CONFIG_USB_DWC3_DUAL_ROLE)),)
>  	dwc3-y				+= host.o
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 48fb264..dbdad87 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -33,6 +33,8 @@
> 
>  #include <linux/phy/phy.h>
> 
> +#define DWC3_MSG_MAX	500
> +
>  /* Global constants */
>  #define DWC3_EP0_BOUNCE_SIZE	512
>  #define DWC3_ENDPOINTS_NUM	32
> diff --git a/drivers/usb/dwc3/debug.c b/drivers/usb/dwc3/debug.c
> new file mode 100644
> index 0000000..6d01e0c
> --- /dev/null
> +++ b/drivers/usb/dwc3/debug.c
> @@ -0,0 +1,33 @@
> +/**
> + * debug.c - DesignWare USB3 DRD Controller Debug/Trace Support
> + *
> + * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
> + *
> + * Author: Felipe Balbi <balbi@ti.com>
> + *
> + * This program is free software: you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2  of
> + * the License as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include "debug.h"
> +
> +void dwc3_trace(void (*trace)(struct va_format *),
> +		const char *fmt, ...)

Unnecessary line wrap? It looks like this would fit on one line.

> +{
> +	struct va_format vaf;
> +	va_list args;
> +
> +	va_start(args, fmt);
> +	vaf.fmt = fmt;
> +	vaf.va = &args;
> +
> +	trace(&vaf);
> +
> +	va_end(args);
> +}
> diff --git a/drivers/usb/dwc3/debug.h b/drivers/usb/dwc3/debug.h
> index 12ff4c9..3dfcd15 100644
> --- a/drivers/usb/dwc3/debug.h
> +++ b/drivers/usb/dwc3/debug.h
> @@ -214,6 +214,9 @@ static inline const char *dwc3_gadget_event_type_string(u8 event)
>  	}
>  }
> 
> +void dwc3_trace(void (*trace)(struct va_format *),
> +		const char *fmt, ...);

Same here.

> +
>  #ifdef CONFIG_DEBUG_FS
>  extern int dwc3_debugfs_init(struct dwc3 *);
>  extern void dwc3_debugfs_exit(struct dwc3 *);
> diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
> index 21a3520..79b883f 100644
> --- a/drivers/usb/dwc3/ep0.c
> +++ b/drivers/usb/dwc3/ep0.c
> @@ -65,7 +65,7 @@ static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
> 
>  	dep = dwc->eps[epnum];
>  	if (dep->flags & DWC3_EP_BUSY) {
> -		dev_vdbg(dwc->dev, "%s: still busy\n", dep->name);
> +		dwc3_trace(trace_dwc3_ep0, "%s still busy", dep->name);
>  		return 0;
>  	}
> 
> @@ -88,7 +88,8 @@ static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
>  	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
>  			DWC3_DEPCMD_STARTTRANSFER, &params);
>  	if (ret < 0) {
> -		dev_dbg(dwc->dev, "failed to send STARTTRANSFER command\n");
> +		dwc3_trace(trace_dwc3_ep0, "%s STARTTRANSFER failed",
> +				dep->name);
>  		return ret;
>  	}
> 
> @@ -153,7 +154,8 @@ static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
>  		if (dwc->ep0state == EP0_STATUS_PHASE)
>  			__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
>  		else
> -			dev_dbg(dwc->dev, "too early for delayed status\n");
> +			dwc3_trace(trace_dwc3_ep0,
> +					"too early for delayed status");
> 
>  		return 0;
>  	}
> @@ -217,7 +219,8 @@ int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
> 
>  	spin_lock_irqsave(&dwc->lock, flags);
>  	if (!dep->endpoint.desc) {
> -		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n",
> +		dwc3_trace(trace_dwc3_ep0,
> +				"trying to queue request %p to disabled %s",
>  				request, dep->name);
>  		ret = -ESHUTDOWN;
>  		goto out;
> @@ -229,7 +232,8 @@ int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
>  		goto out;
>  	}
> 
> -	dev_vdbg(dwc->dev, "queueing request %p to %s length %d, state '%s'\n",
> +	dwc3_trace(trace_dwc3_ep0,
> +			"queueing request %p to %s length %d state '%s'",
>  			request, dep->name, request->length,
>  			dwc3_ep0_state_string(dwc->ep0state));
> 
> @@ -485,12 +489,13 @@ static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
> 
>  	addr = le16_to_cpu(ctrl->wValue);
>  	if (addr > 127) {
> -		dev_dbg(dwc->dev, "invalid device address %d\n", addr);
> +		dwc3_trace(trace_dwc3_ep0, "invalid device address %d", addr);
>  		return -EINVAL;
>  	}
> 
>  	if (state == USB_STATE_CONFIGURED) {
> -		dev_dbg(dwc->dev, "trying to set address when configured\n");
> +		dwc3_trace(trace_dwc3_ep0,
> +				"trying to set address when configured");
>  		return -EINVAL;
>  	}
> 
> @@ -556,7 +561,8 @@ static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
>  			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
> 
>  			dwc->resize_fifos = true;
> -			dev_dbg(dwc->dev, "resize fifos flag SET\n");
> +			dwc3_trace(trace_dwc3_ep0,
> +					"resize FIFOs flag SET");

Unnecessary line wrap?

>  		}
>  		break;
> 
> @@ -680,35 +686,35 @@ static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
> 
>  	switch (ctrl->bRequest) {
>  	case USB_REQ_GET_STATUS:
> -		dev_vdbg(dwc->dev, "USB_REQ_GET_STATUS\n");
> +		dwc3_trace(trace_dwc3_ep0, "USB_REQ_GET_STATUS\n");
>  		ret = dwc3_ep0_handle_status(dwc, ctrl);
>  		break;
>  	case USB_REQ_CLEAR_FEATURE:
> -		dev_vdbg(dwc->dev, "USB_REQ_CLEAR_FEATURE\n");
> +		dwc3_trace(trace_dwc3_ep0, "USB_REQ_CLEAR_FEATURE\n");
>  		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
>  		break;
>  	case USB_REQ_SET_FEATURE:
> -		dev_vdbg(dwc->dev, "USB_REQ_SET_FEATURE\n");
> +		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_FEATURE\n");
>  		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
>  		break;
>  	case USB_REQ_SET_ADDRESS:
> -		dev_vdbg(dwc->dev, "USB_REQ_SET_ADDRESS\n");
> +		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_ADDRESS\n");
>  		ret = dwc3_ep0_set_address(dwc, ctrl);
>  		break;
>  	case USB_REQ_SET_CONFIGURATION:
> -		dev_vdbg(dwc->dev, "USB_REQ_SET_CONFIGURATION\n");
> +		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_CONFIGURATION\n");
>  		ret = dwc3_ep0_set_config(dwc, ctrl);
>  		break;
>  	case USB_REQ_SET_SEL:
> -		dev_vdbg(dwc->dev, "USB_REQ_SET_SEL\n");
> +		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_SEL\n");
>  		ret = dwc3_ep0_set_sel(dwc, ctrl);
>  		break;
>  	case USB_REQ_SET_ISOCH_DELAY:
> -		dev_vdbg(dwc->dev, "USB_REQ_SET_ISOCH_DELAY\n");
> +		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_ISOCH_DELAY\n");
>  		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
>  		break;
>  	default:
> -		dev_vdbg(dwc->dev, "Forwarding to gadget driver\n");
> +		dwc3_trace(trace_dwc3_ep0, "Forwarding to gadget driver\n");
>  		ret = dwc3_ep0_delegate_req(dwc, ctrl);
>  		break;
>  	}
> @@ -726,6 +732,8 @@ static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
>  	if (!dwc->gadget_driver)
>  		goto out;
> 
> +	trace_dwc3_ctrl_req(ctrl);

I don't see this function defined anywhere in this patch. Same for some
of the other trace functions. I guess these are automatically defined
by some tracing macro magic? Is there any way to see what the event
will look like short of running the code? These are probably dumb
questions, but I haven't done anything yet with the tracing API, so
I'm pretty clueless about it.

Other than that, I can't think of anything else to be added at this
point. As you say, other trace points can be added later if desired.
Felipe Balbi Aug. 22, 2014, 9:56 p.m. | #2
Hi,

On Fri, Aug 22, 2014 at 09:26:55PM +0000, Paul Zimmerman wrote:
> > diff --git a/drivers/usb/dwc3/debug.c b/drivers/usb/dwc3/debug.c
> > new file mode 100644
> > index 0000000..6d01e0c
> > --- /dev/null
> > +++ b/drivers/usb/dwc3/debug.c
> > @@ -0,0 +1,33 @@
> > +/**
> > + * debug.c - DesignWare USB3 DRD Controller Debug/Trace Support
> > + *
> > + * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
> > + *
> > + * Author: Felipe Balbi <balbi@ti.com>
> > + *
> > + * This program is free software: you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2  of
> > + * the License as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > + * GNU General Public License for more details.
> > + */
> > +
> > +#include "debug.h"
> > +
> > +void dwc3_trace(void (*trace)(struct va_format *),
> > +		const char *fmt, ...)
> 
> Unnecessary line wrap? It looks like this would fit on one line.

fixed all three instances

> > @@ -726,6 +732,8 @@ static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
> >  	if (!dwc->gadget_driver)
> >  		goto out;
> > 
> > +	trace_dwc3_ctrl_req(ctrl);
> 
> I don't see this function defined anywhere in this patch. Same for some
> of the other trace functions. I guess these are automatically defined
> by some tracing macro magic? Is there any way to see what the event

yup, you got it. If you look at trace.h, it defines all the trace points
and on trace.c where we have:

#define CREATE_TRACE_POINTS
#include "trace.h"

that'll cause the creation of all these functions.

> will look like short of running the code? These are probably dumb
> questions, but I haven't done anything yet with the tracing API, so
> I'm pretty clueless about it.

Next week I'll send you a sample output with all events enabled :-)

> Other than that, I can't think of anything else to be added at this
> point. As you say, other trace points can be added later if desired.

Right, I wanted to have a way of using those debug registers (GDBG*) for
tracing the internal HW blocks but there's no documentation about what
those registers mean i.e. how to decode the data returned by them.

Other than that... we might want to, at some point, have a more granular
tracing of the TRB/usb_request lifetime - right now we're only tracing
alloc, queue, dequeue, free - but I guess tracing request accesses alone
is already a pretty good deal, as it can help communicating with IP
folks and giving them a sequence of events for writing RTL simulation
:-)

cheers

Patch

diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
index 10ac3e7..7793e6c 100644
--- a/drivers/usb/dwc3/Makefile
+++ b/drivers/usb/dwc3/Makefile
@@ -1,9 +1,12 @@ 
+# define_trace.h needs to know how to find our header
+CFLAGS_trace.o				:= -I$(src)
+
 ccflags-$(CONFIG_USB_DWC3_DEBUG)	:= -DDEBUG
 ccflags-$(CONFIG_USB_DWC3_VERBOSE)	+= -DVERBOSE_DEBUG
 
 obj-$(CONFIG_USB_DWC3)			+= dwc3.o
 
-dwc3-y					:= core.o
+dwc3-y					:= core.o debug.o trace.o
 
 ifneq ($(filter y,$(CONFIG_USB_DWC3_HOST) $(CONFIG_USB_DWC3_DUAL_ROLE)),)
 	dwc3-y				+= host.o
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 48fb264..dbdad87 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -33,6 +33,8 @@ 
 
 #include <linux/phy/phy.h>
 
+#define DWC3_MSG_MAX	500
+
 /* Global constants */
 #define DWC3_EP0_BOUNCE_SIZE	512
 #define DWC3_ENDPOINTS_NUM	32
diff --git a/drivers/usb/dwc3/debug.c b/drivers/usb/dwc3/debug.c
new file mode 100644
index 0000000..6d01e0c
--- /dev/null
+++ b/drivers/usb/dwc3/debug.c
@@ -0,0 +1,33 @@ 
+/**
+ * debug.c - DesignWare USB3 DRD Controller Debug/Trace Support
+ *
+ * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Author: Felipe Balbi <balbi@ti.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "debug.h"
+
+void dwc3_trace(void (*trace)(struct va_format *),
+		const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start(args, fmt);
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	trace(&vaf);
+
+	va_end(args);
+}
diff --git a/drivers/usb/dwc3/debug.h b/drivers/usb/dwc3/debug.h
index 12ff4c9..3dfcd15 100644
--- a/drivers/usb/dwc3/debug.h
+++ b/drivers/usb/dwc3/debug.h
@@ -214,6 +214,9 @@  static inline const char *dwc3_gadget_event_type_string(u8 event)
 	}
 }
 
+void dwc3_trace(void (*trace)(struct va_format *),
+		const char *fmt, ...);
+
 #ifdef CONFIG_DEBUG_FS
 extern int dwc3_debugfs_init(struct dwc3 *);
 extern void dwc3_debugfs_exit(struct dwc3 *);
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 21a3520..79b883f 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -65,7 +65,7 @@  static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
 
 	dep = dwc->eps[epnum];
 	if (dep->flags & DWC3_EP_BUSY) {
-		dev_vdbg(dwc->dev, "%s: still busy\n", dep->name);
+		dwc3_trace(trace_dwc3_ep0, "%s still busy", dep->name);
 		return 0;
 	}
 
@@ -88,7 +88,8 @@  static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
 	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
 			DWC3_DEPCMD_STARTTRANSFER, &params);
 	if (ret < 0) {
-		dev_dbg(dwc->dev, "failed to send STARTTRANSFER command\n");
+		dwc3_trace(trace_dwc3_ep0, "%s STARTTRANSFER failed",
+				dep->name);
 		return ret;
 	}
 
@@ -153,7 +154,8 @@  static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
 		if (dwc->ep0state == EP0_STATUS_PHASE)
 			__dwc3_ep0_do_control_status(dwc, dwc->eps[direction]);
 		else
-			dev_dbg(dwc->dev, "too early for delayed status\n");
+			dwc3_trace(trace_dwc3_ep0,
+					"too early for delayed status");
 
 		return 0;
 	}
@@ -217,7 +219,8 @@  int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
 
 	spin_lock_irqsave(&dwc->lock, flags);
 	if (!dep->endpoint.desc) {
-		dev_dbg(dwc->dev, "trying to queue request %p to disabled %s\n",
+		dwc3_trace(trace_dwc3_ep0,
+				"trying to queue request %p to disabled %s",
 				request, dep->name);
 		ret = -ESHUTDOWN;
 		goto out;
@@ -229,7 +232,8 @@  int dwc3_gadget_ep0_queue(struct usb_ep *ep, struct usb_request *request,
 		goto out;
 	}
 
-	dev_vdbg(dwc->dev, "queueing request %p to %s length %d, state '%s'\n",
+	dwc3_trace(trace_dwc3_ep0,
+			"queueing request %p to %s length %d state '%s'",
 			request, dep->name, request->length,
 			dwc3_ep0_state_string(dwc->ep0state));
 
@@ -485,12 +489,13 @@  static int dwc3_ep0_set_address(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
 
 	addr = le16_to_cpu(ctrl->wValue);
 	if (addr > 127) {
-		dev_dbg(dwc->dev, "invalid device address %d\n", addr);
+		dwc3_trace(trace_dwc3_ep0, "invalid device address %d", addr);
 		return -EINVAL;
 	}
 
 	if (state == USB_STATE_CONFIGURED) {
-		dev_dbg(dwc->dev, "trying to set address when configured\n");
+		dwc3_trace(trace_dwc3_ep0,
+				"trying to set address when configured");
 		return -EINVAL;
 	}
 
@@ -556,7 +561,8 @@  static int dwc3_ep0_set_config(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
 			dwc3_writel(dwc->regs, DWC3_DCTL, reg);
 
 			dwc->resize_fifos = true;
-			dev_dbg(dwc->dev, "resize fifos flag SET\n");
+			dwc3_trace(trace_dwc3_ep0,
+					"resize FIFOs flag SET");
 		}
 		break;
 
@@ -680,35 +686,35 @@  static int dwc3_ep0_std_request(struct dwc3 *dwc, struct usb_ctrlrequest *ctrl)
 
 	switch (ctrl->bRequest) {
 	case USB_REQ_GET_STATUS:
-		dev_vdbg(dwc->dev, "USB_REQ_GET_STATUS\n");
+		dwc3_trace(trace_dwc3_ep0, "USB_REQ_GET_STATUS\n");
 		ret = dwc3_ep0_handle_status(dwc, ctrl);
 		break;
 	case USB_REQ_CLEAR_FEATURE:
-		dev_vdbg(dwc->dev, "USB_REQ_CLEAR_FEATURE\n");
+		dwc3_trace(trace_dwc3_ep0, "USB_REQ_CLEAR_FEATURE\n");
 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 0);
 		break;
 	case USB_REQ_SET_FEATURE:
-		dev_vdbg(dwc->dev, "USB_REQ_SET_FEATURE\n");
+		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_FEATURE\n");
 		ret = dwc3_ep0_handle_feature(dwc, ctrl, 1);
 		break;
 	case USB_REQ_SET_ADDRESS:
-		dev_vdbg(dwc->dev, "USB_REQ_SET_ADDRESS\n");
+		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_ADDRESS\n");
 		ret = dwc3_ep0_set_address(dwc, ctrl);
 		break;
 	case USB_REQ_SET_CONFIGURATION:
-		dev_vdbg(dwc->dev, "USB_REQ_SET_CONFIGURATION\n");
+		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_CONFIGURATION\n");
 		ret = dwc3_ep0_set_config(dwc, ctrl);
 		break;
 	case USB_REQ_SET_SEL:
-		dev_vdbg(dwc->dev, "USB_REQ_SET_SEL\n");
+		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_SEL\n");
 		ret = dwc3_ep0_set_sel(dwc, ctrl);
 		break;
 	case USB_REQ_SET_ISOCH_DELAY:
-		dev_vdbg(dwc->dev, "USB_REQ_SET_ISOCH_DELAY\n");
+		dwc3_trace(trace_dwc3_ep0, "USB_REQ_SET_ISOCH_DELAY\n");
 		ret = dwc3_ep0_set_isoch_delay(dwc, ctrl);
 		break;
 	default:
-		dev_vdbg(dwc->dev, "Forwarding to gadget driver\n");
+		dwc3_trace(trace_dwc3_ep0, "Forwarding to gadget driver\n");
 		ret = dwc3_ep0_delegate_req(dwc, ctrl);
 		break;
 	}
@@ -726,6 +732,8 @@  static void dwc3_ep0_inspect_setup(struct dwc3 *dwc,
 	if (!dwc->gadget_driver)
 		goto out;
 
+	trace_dwc3_ctrl_req(ctrl);
+
 	len = le16_to_cpu(ctrl->wLength);
 	if (!len) {
 		dwc->three_stage_setup = false;
@@ -774,7 +782,7 @@  static void dwc3_ep0_complete_data(struct dwc3 *dwc,
 
 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
 	if (status == DWC3_TRBSTS_SETUP_PENDING) {
-		dev_dbg(dwc->dev, "Setup Pending received\n");
+		dwc3_trace(trace_dwc3_ep0, "Setup Pending received");
 
 		if (r)
 			dwc3_gadget_giveback(ep0, r, -ECONNRESET);
@@ -834,7 +842,7 @@  static void dwc3_ep0_complete_status(struct dwc3 *dwc,
 
 		ret = dwc3_gadget_set_test_mode(dwc, dwc->test_mode_nr);
 		if (ret < 0) {
-			dev_dbg(dwc->dev, "Invalid Test #%d\n",
+			dwc3_trace(trace_dwc3_ep0, "Invalid Test #%d",
 					dwc->test_mode_nr);
 			dwc3_ep0_stall_and_restart(dwc);
 			return;
@@ -843,7 +851,7 @@  static void dwc3_ep0_complete_status(struct dwc3 *dwc,
 
 	status = DWC3_TRB_SIZE_TRBSTS(trb->size);
 	if (status == DWC3_TRBSTS_SETUP_PENDING)
-		dev_dbg(dwc->dev, "Setup Pending received\n");
+		dwc3_trace(trace_dwc3_ep0, "Setup Pending received\n");
 
 	dwc->ep0state = EP0_SETUP_PHASE;
 	dwc3_ep0_out_start(dwc);
@@ -860,17 +868,17 @@  static void dwc3_ep0_xfer_complete(struct dwc3 *dwc,
 
 	switch (dwc->ep0state) {
 	case EP0_SETUP_PHASE:
-		dev_vdbg(dwc->dev, "Inspecting Setup Bytes\n");
+		dwc3_trace(trace_dwc3_ep0, "Setup Phase");
 		dwc3_ep0_inspect_setup(dwc, event);
 		break;
 
 	case EP0_DATA_PHASE:
-		dev_vdbg(dwc->dev, "Data Phase\n");
+		dwc3_trace(trace_dwc3_ep0, "Data Phase");
 		dwc3_ep0_complete_data(dwc, event);
 		break;
 
 	case EP0_STATUS_PHASE:
-		dev_vdbg(dwc->dev, "Status Phase\n");
+		dwc3_trace(trace_dwc3_ep0, "Status Phase");
 		dwc3_ep0_complete_status(dwc, event);
 		break;
 	default:
@@ -946,7 +954,7 @@  static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)
 {
 	if (dwc->resize_fifos) {
-		dev_dbg(dwc->dev, "starting to resize fifos\n");
+		dwc3_trace(trace_dwc3_ep0, "Resizing FIFOs");
 		dwc3_gadget_resize_tx_fifos(dwc);
 		dwc->resize_fifos = 0;
 	}
@@ -987,7 +995,7 @@  static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
 
 	switch (event->status) {
 	case DEPEVT_STATUS_CONTROL_DATA:
-		dev_vdbg(dwc->dev, "Control Data\n");
+		dwc3_trace(trace_dwc3_ep0, "Control Data");
 
 		/*
 		 * We already have a DATA transfer in the controller's cache,
@@ -1001,7 +1009,8 @@  static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
 		if (dwc->ep0_expect_in != event->endpoint_number) {
 			struct dwc3_ep	*dep = dwc->eps[dwc->ep0_expect_in];
 
-			dev_vdbg(dwc->dev, "Wrong direction for Data phase\n");
+			dwc3_trace(trace_dwc3_ep0,
+					"Wrong direction for Data phase");
 			dwc3_ep0_end_control_data(dwc, dep);
 			dwc3_ep0_stall_and_restart(dwc);
 			return;
@@ -1013,13 +1022,13 @@  static void dwc3_ep0_xfernotready(struct dwc3 *dwc,
 		if (dwc->ep0_next_event != DWC3_EP0_NRDY_STATUS)
 			return;
 
-		dev_vdbg(dwc->dev, "Control Status\n");
+		dwc3_trace(trace_dwc3_ep0, "Control Status");
 
 		dwc->ep0state = EP0_STATUS_PHASE;
 
 		if (dwc->delayed_status) {
 			WARN_ON_ONCE(event->endpoint_number != 1);
-			dev_vdbg(dwc->dev, "Mass Storage delayed status\n");
+			dwc3_trace(trace_dwc3_ep0, "Delayed Status");
 			return;
 		}
 
@@ -1032,7 +1041,7 @@  void dwc3_ep0_interrupt(struct dwc3 *dwc,
 {
 	u8			epnum = event->endpoint_number;
 
-	dev_dbg(dwc->dev, "%s while ep%d%s in state '%s'\n",
+	dwc3_trace(trace_dwc3_ep0, "%s while ep%d%s in state '%s'",
 			dwc3_ep_event_string(event->endpoint_event),
 			epnum >> 1, (epnum & 1) ? "in" : "out",
 			dwc3_ep0_state_string(dwc->ep0state));
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 3ce350f..ca0405c 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -267,6 +267,7 @@  void dwc3_gadget_giveback(struct dwc3_ep *dep, struct dwc3_request *req,
 	dev_dbg(dwc->dev, "request %p from %s completed %d/%d ===> %d\n",
 			req, dep->name, req->request.actual,
 			req->request.length, status);
+	trace_dwc3_gadget_giveback(req);
 
 	spin_unlock(&dwc->lock);
 	req->request.complete(&dep->endpoint, &req->request);
@@ -713,6 +714,8 @@  static struct usb_request *dwc3_gadget_ep_alloc_request(struct usb_ep *ep,
 	req->epnum	= dep->number;
 	req->dep	= dep;
 
+	trace_dwc3_alloc_request(req);
+
 	return &req->request;
 }
 
@@ -721,6 +724,7 @@  static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
 {
 	struct dwc3_request		*req = to_dwc3_request(request);
 
+	trace_dwc3_free_request(req);
 	kfree(req);
 }
 
@@ -1146,6 +1150,7 @@  static int dwc3_gadget_ep_queue(struct usb_ep *ep, struct usb_request *request,
 
 	dev_vdbg(dwc->dev, "queing request %p to %s length %d\n",
 			request, ep->name, request->length);
+	trace_dwc3_ep_queue(req);
 
 	spin_lock_irqsave(&dwc->lock, flags);
 	ret = __dwc3_gadget_ep_queue(dep, req);
@@ -1166,6 +1171,8 @@  static int dwc3_gadget_ep_dequeue(struct usb_ep *ep,
 	unsigned long			flags;
 	int				ret = 0;
 
+	trace_dwc3_ep_dequeue(req);
+
 	spin_lock_irqsave(&dwc->lock, flags);
 
 	list_for_each_entry(r, &dep->request_list, list) {
@@ -1933,9 +1940,6 @@  static void dwc3_endpoint_interrupt(struct dwc3 *dwc,
 	if (!(dep->flags & DWC3_EP_ENABLED))
 		return;
 
-	dev_vdbg(dwc->dev, "%s: %s\n", dep->name,
-			dwc3_ep_event_string(event->endpoint_event));
-
 	if (epnum == 0 || epnum == 1) {
 		dwc3_ep0_interrupt(dwc, event);
 		return;
@@ -2128,8 +2132,6 @@  static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
 {
 	int			reg;
 
-	dev_vdbg(dwc->dev, "%s\n", __func__);
-
 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
 	reg &= ~DWC3_DCTL_INITU1ENA;
 	dwc3_writel(dwc->regs, DWC3_DCTL, reg);
@@ -2148,8 +2150,6 @@  static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
 {
 	u32			reg;
 
-	dev_vdbg(dwc->dev, "%s\n", __func__);
-
 	/*
 	 * WORKAROUND: DWC3 revisions <1.88a have an issue which
 	 * would cause a missing Disconnect Event if there's a
@@ -2234,8 +2234,6 @@  static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
 	u32			reg;
 	u8			speed;
 
-	dev_vdbg(dwc->dev, "%s\n", __func__);
-
 	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
 	speed = reg & DWC3_DSTS_CONNECTSPD;
 	dwc->speed = speed;
@@ -2333,8 +2331,6 @@  static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
 
 static void dwc3_gadget_wakeup_interrupt(struct dwc3 *dwc)
 {
-	dev_vdbg(dwc->dev, "%s\n", __func__);
-
 	/*
 	 * TODO take core out of low power mode when that's
 	 * implemented.
@@ -2439,10 +2435,6 @@  static void dwc3_gadget_linksts_change_interrupt(struct dwc3 *dwc,
 		break;
 	}
 
-	dev_vdbg(dwc->dev, "link change: %s [%d] -> %s [%d]\n",
-			dwc3_gadget_link_string(dwc->link_state),
-			dwc->link_state, dwc3_gadget_link_string(next), next);
-
 	dwc->link_state = next;
 }
 
@@ -2519,6 +2511,8 @@  static void dwc3_gadget_interrupt(struct dwc3 *dwc,
 static void dwc3_process_event_entry(struct dwc3 *dwc,
 		const union dwc3_event *event)
 {
+	trace_dwc3_event(event->raw);
+
 	/* Endpoint IRQ, handle it and return early */
 	if (event->type.is_devspec == 0) {
 		/* depevt */
diff --git a/drivers/usb/dwc3/io.h b/drivers/usb/dwc3/io.h
index d94441c..df8ac17 100644
--- a/drivers/usb/dwc3/io.h
+++ b/drivers/usb/dwc3/io.h
@@ -20,27 +20,51 @@ 
 #define __DRIVERS_USB_DWC3_IO_H
 
 #include <linux/io.h>
-
+#include "trace.h"
+#include "debug.h"
 #include "core.h"
 
 static inline u32 dwc3_readl(void __iomem *base, u32 offset)
 {
+	u32 offs = offset - DWC3_GLOBALS_REGS_START;
+	u32 value;
+
 	/*
 	 * We requested the mem region starting from the Globals address
 	 * space, see dwc3_probe in core.c.
 	 * However, the offsets are given starting from xHCI address space.
 	 */
-	return readl(base + (offset - DWC3_GLOBALS_REGS_START));
+	value = readl(base + offs);
+
+	/*
+	 * When tracing we want to make it easy to find the correct address on
+	 * documentation, so we revert it back to the proper addresses, the
+	 * same way they are described on SNPS documentation
+	 */
+	dwc3_trace(trace_dwc3_readl, "add %p value %08x",
+			base - DWC3_GLOBALS_REGS_START + offset, value);
+
+	return value;
 }
 
 static inline void dwc3_writel(void __iomem *base, u32 offset, u32 value)
 {
+	u32 offs = offset - DWC3_GLOBALS_REGS_START;
+
 	/*
 	 * We requested the mem region starting from the Globals address
 	 * space, see dwc3_probe in core.c.
 	 * However, the offsets are given starting from xHCI address space.
 	 */
-	writel(value, base + (offset - DWC3_GLOBALS_REGS_START));
+	writel(value, base + offs);
+
+	/*
+	 * When tracing we want to make it easy to find the correct address on
+	 * documentation, so we revert it back to the proper addresses, the
+	 * same way they are described on SNPS documentation
+	 */
+	dwc3_trace(trace_dwc3_writel, "addr %p value %08x",
+			base - DWC3_GLOBALS_REGS_START + offset, value);
 }
 
 #endif /* __DRIVERS_USB_DWC3_IO_H */
diff --git a/drivers/usb/dwc3/trace.c b/drivers/usb/dwc3/trace.c
new file mode 100644
index 0000000..6cd1664
--- /dev/null
+++ b/drivers/usb/dwc3/trace.c
@@ -0,0 +1,19 @@ 
+/**
+ * trace.c - DesignWare USB3 DRD Controller Trace Support
+ *
+ * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Author: Felipe Balbi <balbi@ti.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
diff --git a/drivers/usb/dwc3/trace.h b/drivers/usb/dwc3/trace.h
new file mode 100644
index 0000000..1ee041f
--- /dev/null
+++ b/drivers/usb/dwc3/trace.h
@@ -0,0 +1,143 @@ 
+/**
+ * trace.h - DesignWare USB3 DRD Controller Trace Support
+ *
+ * Copyright (C) 2014 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Author: Felipe Balbi <balbi@ti.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM dwc3
+
+#if !defined(__DWC3_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define __DWC3_TRACE_H
+
+#include <linux/types.h>
+#include <linux/tracepoint.h>
+#include <asm/byteorder.h>
+#include "core.h"
+
+DECLARE_EVENT_CLASS(dwc3_log_msg,
+	TP_PROTO(struct va_format *vaf),
+	TP_ARGS(vaf),
+	TP_STRUCT__entry(__dynamic_array(char, msg, DWC3_MSG_MAX)),
+	TP_fast_assign(
+		vsnprintf(__get_str(msg), DWC3_MSG_MAX, vaf->fmt, *vaf->va);
+	),
+	TP_printk("%s", __get_str(msg))
+);
+
+DEFINE_EVENT(dwc3_log_msg, dwc3_readl,
+	TP_PROTO(struct va_format *vaf),
+	TP_ARGS(vaf)
+);
+
+DEFINE_EVENT(dwc3_log_msg, dwc3_writel,
+	TP_PROTO(struct va_format *vaf),
+	TP_ARGS(vaf)
+);
+
+DEFINE_EVENT(dwc3_log_msg, dwc3_ep0,
+	TP_PROTO(struct va_format *vaf),
+	TP_ARGS(vaf)
+);
+
+DECLARE_EVENT_CLASS(dwc3_log_event,
+	TP_PROTO(u32 event),
+	TP_ARGS(event),
+	TP_STRUCT__entry(
+		__field(u32, event)
+	),
+	TP_fast_assign(
+		__entry->event = event;
+	),
+	TP_printk("event %08x\n", __entry->event)
+);
+
+DEFINE_EVENT(dwc3_log_event, dwc3_event,
+	TP_PROTO(u32 event),
+	TP_ARGS(event)
+);
+
+DECLARE_EVENT_CLASS(dwc3_log_ctrl,
+	TP_PROTO(struct usb_ctrlrequest *ctrl),
+	TP_ARGS(ctrl),
+	TP_STRUCT__entry(
+		__field(struct usb_ctrlrequest *, ctrl)
+	),
+	TP_fast_assign(
+		__entry->ctrl = ctrl;
+	),
+	TP_printk("bRequestType %02x bRequest %02x wValue %04x wIndex %04x wLength %d",
+		__entry->ctrl->bRequestType, __entry->ctrl->bRequest,
+		le16_to_cpu(__entry->ctrl->wValue), le16_to_cpu(__entry->ctrl->wIndex),
+		le16_to_cpu(__entry->ctrl->wLength)
+	)
+);
+
+DEFINE_EVENT(dwc3_log_ctrl, dwc3_ctrl_req,
+	TP_PROTO(struct usb_ctrlrequest *ctrl),
+	TP_ARGS(ctrl)
+);
+
+DECLARE_EVENT_CLASS(dwc3_log_request,
+	TP_PROTO(struct dwc3_request *req),
+	TP_ARGS(req),
+	TP_STRUCT__entry(
+		__field(struct dwc3_request *, req)
+	),
+	TP_fast_assign(
+		__entry->req = req;
+	),
+	TP_printk("%s: %s req %p length %u/%u ==> %d",
+		__entry->req->dep->name, __entry->req,
+		__entry->req->request.actual, __entry->req->request.length,
+		__entry->req->request.status
+	)
+);
+
+DEFINE_EVENT(dwc3_log_request, dwc3_alloc_request,
+	TP_PROTO(struct dwc3_request *req),
+	TP_ARGS(req)
+);
+
+DEFINE_EVENT(dwc3_log_request, dwc3_free_request,
+	TP_PROTO(struct dwc3_request *req),
+	TP_ARGS(req)
+);
+
+DEFINE_EVENT(dwc3_log_request, dwc3_ep_queue,
+	TP_PROTO(struct dwc3_request *req),
+	TP_ARGS(req)
+);
+
+DEFINE_EVENT(dwc3_log_request, dwc3_ep_dequeue,
+	TP_PROTO(struct dwc3_request *req),
+	TP_ARGS(req)
+);
+
+DEFINE_EVENT(dwc3_log_request, dwc3_gadget_giveback,
+	TP_PROTO(struct dwc3_request *req),
+	TP_ARGS(req)
+);
+
+#endif /* __DWC3_TRACE_H */
+
+/* this part has to be here */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+
+#include <trace/define_trace.h>