diff mbox series

[v2,3/3] usb: gadget: f_fs: add dev name as prefix for pr_vdebug()

Message ID 1679638227-20496-3-git-send-email-quic_linyyuan@quicinc.com (mailing list archive)
State New, archived
Headers show
Series [v2,1/3] usb: gadget: f_fs: remove ENTER() macro | expand

Commit Message

Linyu Yuan March 24, 2023, 6:10 a.m. UTC 
when multiple instances in use, the debug message is hard to understand
as there is no instance name show.

this change will show each instance name for debug messages.

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
---
v2: split to several changes according to v1 comments
v1: https://lore.kernel.org/linux-usb/1679481369-30094-1-git-send-email-quic_linyyuan@quicinc.com/

 drivers/usb/gadget/function/f_fs.c | 136 +++++++++++++++++++------------------
 1 file changed, 69 insertions(+), 67 deletions(-)

Comments

Greg KH March 25, 2023, 9 a.m. UTC | #1 
On Fri, Mar 24, 2023 at 02:10:27PM +0800, Linyu Yuan wrote:
> when multiple instances in use, the debug message is hard to understand
> as there is no instance name show.
> 
> this change will show each instance name for debug messages.
> 
> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> ---
> v2: split to several changes according to v1 comments
> v1: https://lore.kernel.org/linux-usb/1679481369-30094-1-git-send-email-quic_linyyuan@quicinc.com/
> 
>  drivers/usb/gadget/function/f_fs.c | 136 +++++++++++++++++++------------------
>  1 file changed, 69 insertions(+), 67 deletions(-)
> 
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index a4051c8..df67ab5 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -317,12 +317,12 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
>  static int __ffs_ep0_stall(struct ffs_data *ffs)
>  {
>  	if (ffs->ev.can_stall) {
> -		pr_vdebug("ep0 stall\n");
> +		pr_vdebug("%s: ep0 stall\n", ffs->dev_name);

Again, no, please use dev_dbg() instead.  Do NOT roll your own debugging
macros.  You have access to a struct device pointer for this device that
the driver is controlling, so please always use that instead.

thanks,

greg k-h
Linyu Yuan March 26, 2023, 2:55 a.m. UTC | #2 
On 3/25/2023 5:00 PM, Greg Kroah-Hartman wrote:
> On Fri, Mar 24, 2023 at 02:10:27PM +0800, Linyu Yuan wrote:
>> when multiple instances in use, the debug message is hard to understand
>> as there is no instance name show.
>>
>> this change will show each instance name for debug messages.
>>
>> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
>> ---
>> v2: split to several changes according to v1 comments
>> v1: https://lore.kernel.org/linux-usb/1679481369-30094-1-git-send-email-quic_linyyuan@quicinc.com/
>>
>>   drivers/usb/gadget/function/f_fs.c | 136 +++++++++++++++++++------------------
>>   1 file changed, 69 insertions(+), 67 deletions(-)
>>
>> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
>> index a4051c8..df67ab5 100644
>> --- a/drivers/usb/gadget/function/f_fs.c
>> +++ b/drivers/usb/gadget/function/f_fs.c
>> @@ -317,12 +317,12 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
>>   static int __ffs_ep0_stall(struct ffs_data *ffs)
>>   {
>>   	if (ffs->ev.can_stall) {
>> -		pr_vdebug("ep0 stall\n");
>> +		pr_vdebug("%s: ep0 stall\n", ffs->dev_name);
> Again, no, please use dev_dbg() instead.  Do NOT roll your own debugging
> macros.  You have access to a struct device pointer for this device that
> the driver is controlling, so please always use that instead.


thanks for your suggestion, i didn't know dev_dbg can accept NULL dev 
pointer

as this driver have no real struct device.


will change to dev_dbg with NULL dev pointer.



>
> thanks,
>
> greg k-h
Greg KH March 26, 2023, 6:29 a.m. UTC | #3 
On Sun, Mar 26, 2023 at 10:55:18AM +0800, Linyu Yuan wrote:
> 
> On 3/25/2023 5:00 PM, Greg Kroah-Hartman wrote:
> > On Fri, Mar 24, 2023 at 02:10:27PM +0800, Linyu Yuan wrote:
> > > when multiple instances in use, the debug message is hard to understand
> > > as there is no instance name show.
> > > 
> > > this change will show each instance name for debug messages.
> > > 
> > > Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> > > ---
> > > v2: split to several changes according to v1 comments
> > > v1: https://lore.kernel.org/linux-usb/1679481369-30094-1-git-send-email-quic_linyyuan@quicinc.com/
> > > 
> > >   drivers/usb/gadget/function/f_fs.c | 136 +++++++++++++++++++------------------
> > >   1 file changed, 69 insertions(+), 67 deletions(-)
> > > 
> > > diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> > > index a4051c8..df67ab5 100644
> > > --- a/drivers/usb/gadget/function/f_fs.c
> > > +++ b/drivers/usb/gadget/function/f_fs.c
> > > @@ -317,12 +317,12 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
> > >   static int __ffs_ep0_stall(struct ffs_data *ffs)
> > >   {
> > >   	if (ffs->ev.can_stall) {
> > > -		pr_vdebug("ep0 stall\n");
> > > +		pr_vdebug("%s: ep0 stall\n", ffs->dev_name);
> > Again, no, please use dev_dbg() instead.  Do NOT roll your own debugging
> > macros.  You have access to a struct device pointer for this device that
> > the driver is controlling, so please always use that instead.
> 
> 
> thanks for your suggestion, i didn't know dev_dbg can accept NULL dev
> pointer
> 
> as this driver have no real struct device.

That is not true, you have access to a struct usb_gadget, which is a
struct device.  Use that please.

> will change to dev_dbg with NULL dev pointer.

No, that is pointless, please do not do that.

thanks,

greg k-h
Linyu Yuan March 27, 2023, 1:54 a.m. UTC | #4 
On 3/26/2023 2:29 PM, Greg Kroah-Hartman wrote:
> On Sun, Mar 26, 2023 at 10:55:18AM +0800, Linyu Yuan wrote:
>> On 3/25/2023 5:00 PM, Greg Kroah-Hartman wrote:
>>> On Fri, Mar 24, 2023 at 02:10:27PM +0800, Linyu Yuan wrote:
>>>> when multiple instances in use, the debug message is hard to understand
>>>> as there is no instance name show.
>>>>
>>>> this change will show each instance name for debug messages.
>>>>
>>>> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
>>>> ---
>>>> v2: split to several changes according to v1 comments
>>>> v1: https://lore.kernel.org/linux-usb/1679481369-30094-1-git-send-email-quic_linyyuan@quicinc.com/
>>>>
>>>>    drivers/usb/gadget/function/f_fs.c | 136 +++++++++++++++++++------------------
>>>>    1 file changed, 69 insertions(+), 67 deletions(-)
>>>>
>>>> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
>>>> index a4051c8..df67ab5 100644
>>>> --- a/drivers/usb/gadget/function/f_fs.c
>>>> +++ b/drivers/usb/gadget/function/f_fs.c
>>>> @@ -317,12 +317,12 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
>>>>    static int __ffs_ep0_stall(struct ffs_data *ffs)
>>>>    {
>>>>    	if (ffs->ev.can_stall) {
>>>> -		pr_vdebug("ep0 stall\n");
>>>> +		pr_vdebug("%s: ep0 stall\n", ffs->dev_name);
>>> Again, no, please use dev_dbg() instead.  Do NOT roll your own debugging
>>> macros.  You have access to a struct device pointer for this device that
>>> the driver is controlling, so please always use that instead.
>>
>> thanks for your suggestion, i didn't know dev_dbg can accept NULL dev
>> pointer
>>
>> as this driver have no real struct device.
> That is not true, you have access to a struct usb_gadget, which is a
> struct device.  Use that please.

but this is not good, as for gadget/udc, from my view, there are two layer,

one configfs driver, one lower UDC, only after bind, there will be a 
reference to usb_gadget.

but configuration to driver can happen before bind, if so the usb_gadget 
will be NULL.


>
>> will change to dev_dbg with NULL dev pointer.
> No, that is pointless, please do not do that.
>
> thanks,
>
> greg k-h
Greg KH March 27, 2023, 5:46 a.m. UTC | #5 
On Mon, Mar 27, 2023 at 09:54:11AM +0800, Linyu Yuan wrote:
> 
> On 3/26/2023 2:29 PM, Greg Kroah-Hartman wrote:
> > On Sun, Mar 26, 2023 at 10:55:18AM +0800, Linyu Yuan wrote:
> > > On 3/25/2023 5:00 PM, Greg Kroah-Hartman wrote:
> > > > On Fri, Mar 24, 2023 at 02:10:27PM +0800, Linyu Yuan wrote:
> > > > > when multiple instances in use, the debug message is hard to understand
> > > > > as there is no instance name show.
> > > > > 
> > > > > this change will show each instance name for debug messages.
> > > > > 
> > > > > Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> > > > > ---
> > > > > v2: split to several changes according to v1 comments
> > > > > v1: https://lore.kernel.org/linux-usb/1679481369-30094-1-git-send-email-quic_linyyuan@quicinc.com/
> > > > > 
> > > > >    drivers/usb/gadget/function/f_fs.c | 136 +++++++++++++++++++------------------
> > > > >    1 file changed, 69 insertions(+), 67 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> > > > > index a4051c8..df67ab5 100644
> > > > > --- a/drivers/usb/gadget/function/f_fs.c
> > > > > +++ b/drivers/usb/gadget/function/f_fs.c
> > > > > @@ -317,12 +317,12 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
> > > > >    static int __ffs_ep0_stall(struct ffs_data *ffs)
> > > > >    {
> > > > >    	if (ffs->ev.can_stall) {
> > > > > -		pr_vdebug("ep0 stall\n");
> > > > > +		pr_vdebug("%s: ep0 stall\n", ffs->dev_name);
> > > > Again, no, please use dev_dbg() instead.  Do NOT roll your own debugging
> > > > macros.  You have access to a struct device pointer for this device that
> > > > the driver is controlling, so please always use that instead.
> > > 
> > > thanks for your suggestion, i didn't know dev_dbg can accept NULL dev
> > > pointer
> > > 
> > > as this driver have no real struct device.
> > That is not true, you have access to a struct usb_gadget, which is a
> > struct device.  Use that please.
> 
> but this is not good, as for gadget/udc, from my view, there are two layer,
> 
> one configfs driver, one lower UDC, only after bind, there will be a
> reference to usb_gadget.
> 
> but configuration to driver can happen before bind, if so the usb_gadget
> will be NULL.

But is that where this debug message is being called?  This is a
function while the driver is bound to a device, so you have a usb_gadget
pointer here.

If you have messages that could happen before the device is bound, sure,
don't use the device there.

thanks,

greg k-h
diff mbox series

Patch

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index a4051c8..df67ab5 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -317,12 +317,12 @@  static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
 static int __ffs_ep0_stall(struct ffs_data *ffs)
 {
 	if (ffs->ev.can_stall) {
-		pr_vdebug("ep0 stall\n");
+		pr_vdebug("%s: ep0 stall\n", ffs->dev_name);
 		usb_ep_set_halt(ffs->gadget->ep0);
 		ffs->setup_state = FFS_NO_SETUP;
 		return -EL2HLT;
 	} else {
-		pr_debug("bogus ep0 stall!\n");
+		pr_debug("%s: bogus ep0 stall!\n", ffs->dev_name);
 		return -ESRCH;
 	}
 }
@@ -361,7 +361,7 @@  static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
 
 		/* Handle data */
 		if (ffs->state == FFS_READ_DESCRIPTORS) {
-			pr_info("read descriptors\n");
+			pr_info("%s: read descriptors\n", ffs->dev_name);
 			ret = __ffs_data_got_descs(ffs, data, len);
 			if (ret < 0)
 				break;
@@ -369,7 +369,7 @@  static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
 			ffs->state = FFS_READ_STRINGS;
 			ret = len;
 		} else {
-			pr_info("read strings\n");
+			pr_info("%s: read strings\n", ffs->dev_name);
 			ret = __ffs_data_got_strings(ffs, data, len);
 			if (ret < 0)
 				break;
@@ -749,9 +749,9 @@  static ssize_t ffs_copy_to_iter(struct ffs_data *ffs, void *data, int data_len,
 	 * aio_read(2) etc. system calls.  Writing data to an IN endpoint is not
 	 * affected.
 	 */
-	pr_err("functionfs read size %d > requested size %zd, dropping excess data. "
+	pr_err("%s: functionfs read size %d > requested size %zd, dropping excess data. "
 	       "Align read buffer size to max packet size to avoid the problem.\n",
-	       data_len, ret);
+	       ffs->dev_name, data_len, ret);
 
 	return ret;
 }
@@ -911,8 +911,8 @@  static ssize_t __ffs_epfile_read_data(struct ffs_epfile *epfile,
 		return -EFAULT;
 
 	/* See ffs_copy_to_iter for more context. */
-	pr_warn("functionfs read size %d > requested size %zd, splitting request into multiple reads.",
-		data_len, ret);
+	pr_warn("%s: functionfs read size %d > requested size %zd, splitting request into multiple reads.",
+		epfile->ffs->dev_name, data_len, ret);
 
 	data_len -= ret;
 	buf = kmalloc(struct_size(buf, storage, data_len), GFP_KERNEL);
@@ -1043,7 +1043,7 @@  static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 		 * For such reason, we're adding this redundant sanity check
 		 * here.
 		 */
-		WARN(1, "%s: data_len == -EINVAL\n", __func__);
+		WARN(1, "%s: %s(): data_len == -EINVAL\n", epfile->ffs->dev_name, __func__);
 		ret = -EINVAL;
 	} else if (!io_data->aio) {
 		bool interrupted = false;
@@ -1665,7 +1665,7 @@  static void ffs_data_opened(struct ffs_data *ffs)
 static void ffs_data_put(struct ffs_data *ffs)
 {
 	if (refcount_dec_and_test(&ffs->ref)) {
-		pr_info("%s(): freeing\n", __func__);
+		pr_info("%s: %s(): freeing\n", ffs->dev_name, __func__);
 		ffs_data_clear(ffs);
 		ffs_release_dev(ffs->private_data);
 		BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
@@ -1942,8 +1942,8 @@  static int ffs_func_eps_enable(struct ffs_function *func)
 
 		ret = config_ep_by_speed(func->gadget, &func->function, ep->ep);
 		if (ret) {
-			pr_err("%s: config_ep_by_speed(%s) returned %d\n",
-					__func__, ep->ep->name, ret);
+			pr_err("%s: %s(): config_ep_by_speed(%s) returned %d\n",
+					ffs->dev_name, __func__, ep->ep->name, ret);
 			break;
 		}
 
@@ -2003,14 +2003,14 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 
 	/* At least two bytes are required: length and type */
 	if (len < 2) {
-		pr_vdebug("descriptor too short\n");
+		pr_vdebug("%s: descriptor too short\n", ffs->dev_name);
 		return -EINVAL;
 	}
 
 	/* If we have at least as many bytes as the descriptor takes? */
 	length = _ds->bLength;
 	if (len < length) {
-		pr_vdebug("descriptor longer then available data\n");
+		pr_vdebug("%s: descriptor longer then available data\n", ffs->dev_name);
 		return -EINVAL;
 	}
 
@@ -2018,15 +2018,15 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 #define __entity_check_STRING(val)     (val)
 #define __entity_check_ENDPOINT(val)   ((val) & USB_ENDPOINT_NUMBER_MASK)
 #define __entity(type, val) do {					\
-		pr_vdebug("entity " #type "(%02x)\n", (val));		\
+		pr_vdebug("%s: entity " #type "(%02x)\n", ffs->dev_name, (val));	\
 		if (!__entity_check_ ##type(val)) {			\
-			pr_vdebug("invalid entity's value\n");		\
+			pr_vdebug("%s: invalid entity's value\n", ffs->dev_name);	\
 			return -EINVAL;					\
 		}							\
-		ret = entity(ffs, FFS_ ##type, &val, _ds, priv);		\
+		ret = entity(ffs, FFS_ ##type, &val, _ds, priv);	\
 		if (ret < 0) {						\
-			pr_debug("entity " #type "(%02x); ret = %d\n",	\
-				 (val), ret);				\
+			pr_debug("%s: entity " #type "(%02x); ret = %d\n",	\
+				 ffs->dev_name, (val), ret);		\
 			return ret;					\
 		}							\
 	} while (0)
@@ -2038,13 +2038,13 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 	case USB_DT_STRING:
 	case USB_DT_DEVICE_QUALIFIER:
 		/* function can't have any of those */
-		pr_vdebug("descriptor reserved for gadget: %d\n",
-		      _ds->bDescriptorType);
+		pr_vdebug("%s: descriptor reserved for gadget: %d\n",
+		      ffs->dev_name, _ds->bDescriptorType);
 		return -EINVAL;
 
 	case USB_DT_INTERFACE: {
 		struct usb_interface_descriptor *ds = (void *)_ds;
-		pr_vdebug("interface descriptor\n");
+		pr_vdebug("%s: interface descriptor\n", ffs->dev_name);
 		if (length != sizeof *ds)
 			goto inv_length;
 
@@ -2057,7 +2057,7 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 
 	case USB_DT_ENDPOINT: {
 		struct usb_endpoint_descriptor *ds = (void *)_ds;
-		pr_vdebug("endpoint descriptor\n");
+		pr_vdebug("%s: endpoint descriptor\n", ffs->dev_name);
 		if (length != USB_DT_ENDPOINT_SIZE &&
 		    length != USB_DT_ENDPOINT_AUDIO_SIZE)
 			goto inv_length;
@@ -2067,18 +2067,18 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 
 	case USB_TYPE_CLASS | 0x01:
 		if (*current_class == USB_INTERFACE_CLASS_HID) {
-			pr_vdebug("hid descriptor\n");
+			pr_vdebug("%s: hid descriptor\n", ffs->dev_name);
 			if (length != sizeof(struct hid_descriptor))
 				goto inv_length;
 			break;
 		} else if (*current_class == USB_INTERFACE_CLASS_CCID) {
-			pr_vdebug("ccid descriptor\n");
+			pr_vdebug("%s: ccid descriptor\n", ffs->dev_name);
 			if (length != sizeof(struct ccid_descriptor))
 				goto inv_length;
 			break;
 		} else {
-			pr_vdebug("unknown descriptor: %d for class %d\n",
-			      _ds->bDescriptorType, *current_class);
+			pr_vdebug("%s: unknown descriptor: %d for class %d\n",
+			      ffs->dev_name, _ds->bDescriptorType, *current_class);
 			return -EINVAL;
 		}
 
@@ -2089,7 +2089,7 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 
 	case USB_DT_INTERFACE_ASSOCIATION: {
 		struct usb_interface_assoc_descriptor *ds = (void *)_ds;
-		pr_vdebug("interface association descriptor\n");
+		pr_vdebug("%s: interface association descriptor\n", ffs->dev_name);
 		if (length != sizeof *ds)
 			goto inv_length;
 		if (ds->iFunction)
@@ -2098,7 +2098,7 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 		break;
 
 	case USB_DT_SS_ENDPOINT_COMP:
-		pr_vdebug("EP SS companion descriptor\n");
+		pr_vdebug("%s: EP SS companion descriptor\n", ffs->dev_name);
 		if (length != sizeof(struct usb_ss_ep_comp_descriptor))
 			goto inv_length;
 		break;
@@ -2109,17 +2109,18 @@  static int __must_check ffs_do_single_desc(struct ffs_data *ffs, char *data, uns
 	case USB_DT_SECURITY:
 	case USB_DT_CS_RADIO_CONTROL:
 		/* TODO */
-		pr_vdebug("unimplemented descriptor: %d\n", _ds->bDescriptorType);
+		pr_vdebug("%s: unimplemented descriptor: %d\n", ffs->dev_name,
+			_ds->bDescriptorType);
 		return -EINVAL;
 
 	default:
 		/* We should never be here */
-		pr_vdebug("unknown descriptor: %d\n", _ds->bDescriptorType);
+		pr_vdebug("%s: unknown descriptor: %d\n", ffs->dev_name, _ds->bDescriptorType);
 		return -EINVAL;
 
 inv_length:
-		pr_vdebug("invalid length: %d (descriptor %d)\n",
-			  _ds->bLength, _ds->bDescriptorType);
+		pr_vdebug("%s: invalid length: %d (descriptor %d)\n",
+			  ffs->dev_name, _ds->bLength, _ds->bDescriptorType);
 		return -EINVAL;
 	}
 
@@ -2148,8 +2149,8 @@  static int __must_check ffs_do_descs(struct ffs_data *ffs, unsigned count, char
 		/* Record "descriptor" entity */
 		ret = entity(ffs, FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
 		if (ret < 0) {
-			pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
-				 num, ret);
+			pr_debug("%s: entity DESCRIPTOR(%02lx); ret = %d\n",
+				 ffs->dev_name, num, ret);
 			return ret;
 		}
 
@@ -2159,7 +2160,7 @@  static int __must_check ffs_do_descs(struct ffs_data *ffs, unsigned count, char
 		ret = ffs_do_single_desc(ffs, data, len, entity, priv,
 			&current_class);
 		if (ret < 0) {
-			pr_debug("%s returns %d\n", __func__, ret);
+			pr_debug("%s: %s(): returns %d\n", ffs->dev_name, __func__, ret);
 			return ret;
 		}
 
@@ -2224,11 +2225,12 @@  static int __ffs_do_os_desc_header(struct ffs_data *ffs, enum ffs_os_desc_type *
 	u16 w_index = le16_to_cpu(desc->wIndex);
 
 	if (bcd_version == 0x1) {
-		pr_warn("bcdVersion must be 0x0100, stored in Little Endian order. "
-			"Userspace driver should be fixed, accepting 0x0001 for compatibility.\n");
+		pr_warn("%s: bcdVersion must be 0x0100, stored in Little Endian order. "
+			"Userspace driver should be fixed, accepting 0x0001 for compatibility.\n",
+			ffs->dev_name);
 	} else if (bcd_version != 0x100) {
-		pr_vdebug("unsupported os descriptors version: 0x%x\n",
-			  bcd_version);
+		pr_vdebug("%s: unsupported os descriptors version: 0x%x\n",
+			  ffs->dev_name, bcd_version);
 		return -EINVAL;
 	}
 	switch (w_index) {
@@ -2239,7 +2241,7 @@  static int __ffs_do_os_desc_header(struct ffs_data *ffs, enum ffs_os_desc_type *
 		*next_type = FFS_OS_DESC_EXT_PROP;
 		break;
 	default:
-		pr_vdebug("unsupported os descriptor type: %d", w_index);
+		pr_vdebug("%s: unsupported os descriptor type: %d", ffs->dev_name, w_index);
 		return -EINVAL;
 	}
 
@@ -2264,7 +2266,7 @@  static int __must_check ffs_do_single_os_desc(struct ffs_data *ffs, char *data,
 	while (feature_count--) {
 		ret = entity(ffs, type, h, data, len, priv);
 		if (ret < 0) {
-			pr_debug("bad OS descriptor, type: %d\n", type);
+			pr_debug("%s: bad OS descriptor, type: %d\n", ffs->dev_name, type);
 			return ret;
 		}
 		data += ret;
@@ -2302,8 +2304,8 @@  static int __must_check ffs_do_os_descs(struct ffs_data *ffs, unsigned count,
 
 		ret = __ffs_do_os_desc_header(ffs, &type, desc);
 		if (ret < 0) {
-			pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
-				 num, ret);
+			pr_debug("%s: entity OS_DESCRIPTOR(%02lx); ret = %d\n",
+				 ffs->dev_name, num, ret);
 			return ret;
 		}
 		/*
@@ -2323,7 +2325,7 @@  static int __must_check ffs_do_os_descs(struct ffs_data *ffs, unsigned count,
 		ret = ffs_do_single_os_desc(ffs, data, len, type,
 					    feature_count, entity, priv, desc);
 		if (ret < 0) {
-			pr_debug("%s returns %d\n", __func__, ret);
+			pr_debug("%s: %s() returns %d\n", ffs->dev_name, __func__, ret);
 			return ret;
 		}
 
@@ -2357,7 +2359,7 @@  static int __ffs_data_do_os_desc(struct ffs_data *ffs, enum ffs_os_desc_type typ
 			 * values.  We fix it here to avoid returning EINVAL
 			 * in response to values we used to accept.
 			 */
-			pr_debug("usb_ext_compat_desc::Reserved1 forced to 1\n");
+			pr_debug("%s: usb_ext_compat_desc::Reserved1 forced to 1\n", ffs->dev_name);
 			d->Reserved1 = 1;
 		}
 		for (i = 0; i < ARRAY_SIZE(d->Reserved2); ++i)
@@ -2380,20 +2382,20 @@  static int __ffs_data_do_os_desc(struct ffs_data *ffs, enum ffs_os_desc_type typ
 		type = le32_to_cpu(d->dwPropertyDataType);
 		if (type < USB_EXT_PROP_UNICODE ||
 		    type > USB_EXT_PROP_UNICODE_MULTI) {
-			pr_vdebug("unsupported os descriptor property type: %d",
-				  type);
+			pr_vdebug("%s: unsupported os descriptor property type: %d",
+				  ffs->dev_name, type);
 			return -EINVAL;
 		}
 		pnl = le16_to_cpu(d->wPropertyNameLength);
 		if (length < 14 + pnl) {
-			pr_vdebug("invalid os descriptor length: %d pnl:%d (descriptor %d)\n",
-				  length, pnl, type);
+			pr_vdebug("%s: invalid os descriptor length: %d pnl:%d (%d)\n",
+				  ffs->dev_name, length, pnl, type);
 			return -EINVAL;
 		}
 		pdl = le32_to_cpu(*(__le32 *)((u8 *)data + 10 + pnl));
 		if (length != 14 + pnl + pdl) {
-			pr_vdebug("invalid os descriptor length: %d pnl:%d pdl:%d (descriptor %d)\n",
-				  length, pnl, pdl, type);
+			pr_vdebug("%s: invalid os descriptor length: %d pnl:%d pdl:%d (%d)\n",
+				ffs->dev_name, length, pnl, pdl, type);
 			return -EINVAL;
 		}
 		++ffs->ms_os_descs_ext_prop_count;
@@ -2403,7 +2405,7 @@  static int __ffs_data_do_os_desc(struct ffs_data *ffs, enum ffs_os_desc_type typ
 	}
 		break;
 	default:
-		pr_vdebug("unknown descriptor: %d\n", type);
+		pr_vdebug("%s: unknown descriptor: %d\n", ffs->dev_name, type);
 		return -EINVAL;
 	}
 	return length;
@@ -2718,7 +2720,7 @@  static void __ffs_event_add(struct ffs_data *ffs,
 		break;
 
 	default:
-		WARN(1, "%d: unknown event, this should not happen\n", type);
+		WARN(1, "%s: %d: unknown event, this should not happen\n", ffs->dev_name, type);
 		return;
 	}
 
@@ -2729,11 +2731,11 @@  static void __ffs_event_add(struct ffs_data *ffs,
 			if ((*ev == rem_type1 || *ev == rem_type2) == neg)
 				*out++ = *ev;
 			else
-				pr_vdebug("purging event %d\n", *ev);
+				pr_vdebug("%s: purging event %d\n", ffs->dev_name, *ev);
 		ffs->ev.count = out - ffs->ev.types;
 	}
 
-	pr_vdebug("adding event %d\n", type);
+	pr_vdebug("%s: adding event %d\n", ffs->dev_name, type);
 	ffs->ev.types[ffs->ev.count++] = type;
 	wake_up_locked(&ffs->ev.waitq);
 	if (ffs->ffs_eventfd)
@@ -2802,8 +2804,8 @@  static int __ffs_func_bind_do_descs(struct ffs_data *ffs, enum ffs_entity_type t
 	ffs_ep = func->eps + idx;
 
 	if (ffs_ep->descs[ep_desc_id]) {
-		pr_err("two %sspeed descriptors for EP %d\n",
-			  speed_names[ep_desc_id],
+		pr_err("%s: two %sspeed descriptors for EP %d\n",
+			  ffs->dev_name, speed_names[ep_desc_id],
 			  ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 		return -EINVAL;
 	}
@@ -2830,7 +2832,7 @@  static int __ffs_func_bind_do_descs(struct ffs_data *ffs, enum ffs_entity_type t
 		 * endpoint descriptors as if they were full speed.
 		 */
 		wMaxPacketSize = ds->wMaxPacketSize;
-		pr_vdebug("autoconfig\n");
+		pr_vdebug("%s: autoconfig\n", ffs->dev_name);
 		ep = usb_ep_autoconfig(func->gadget, ds);
 		if (!ep)
 			return -ENOTSUPP;
@@ -2911,7 +2913,7 @@  static int __ffs_func_bind_do_nums(struct ffs_data *ffs, enum ffs_entity_type ty
 		break;
 	}
 
-	pr_vdebug("%02x -> %02x\n", *valuep, newValue);
+	pr_vdebug("%s: %02x -> %02x\n", ffs->dev_name, *valuep, newValue);
 	*valuep = newValue;
 	return 0;
 }
@@ -2989,7 +2991,7 @@  static int __ffs_func_bind_do_os_desc(struct ffs_data *ffs, enum ffs_os_desc_typ
 	}
 		break;
 	default:
-		pr_vdebug("unknown descriptor: %d\n", type);
+		pr_vdebug("%s: unknown descriptor: %d\n", ffs->dev_name, type);
 	}
 
 	return length;
@@ -3283,11 +3285,11 @@  static int ffs_func_setup(struct usb_function *f,
 	unsigned long flags;
 	int ret;
 
-	pr_vdebug("creq->bRequestType = %02x\n", creq->bRequestType);
-	pr_vdebug("creq->bRequest     = %02x\n", creq->bRequest);
-	pr_vdebug("creq->wValue       = %04x\n", le16_to_cpu(creq->wValue));
-	pr_vdebug("creq->wIndex       = %04x\n", le16_to_cpu(creq->wIndex));
-	pr_vdebug("creq->wLength      = %04x\n", le16_to_cpu(creq->wLength));
+	pr_vdebug("%s: creq->bRequestType = %02x\n", ffs->dev_name, creq->bRequestType);
+	pr_vdebug("%s: creq->bRequest     = %02x\n", ffs->dev_name, creq->bRequest);
+	pr_vdebug("%s: creq->wValue       = %04x\n", ffs->dev_name, le16_to_cpu(creq->wValue));
+	pr_vdebug("%s: creq->wIndex       = %04x\n", ffs->dev_name, le16_to_cpu(creq->wIndex));
+	pr_vdebug("%s: creq->wLength      = %04x\n", ffs->dev_name, le16_to_cpu(creq->wLength));
 
 	/*
 	 * Most requests directed to interface go through here
@@ -3790,7 +3792,7 @@  static char *ffs_prepare_buffer(struct ffs_data *ffs, const char __user *buf, si
 	if (IS_ERR(data))
 		return data;
 
-	pr_vdebug("Buffer from user space:\n");
+	pr_vdebug("%s: Buffer from user space:\n", ffs->dev_name);
 	ffs_dump_mem("", data, len);
 
 	return data;