[PATCH] usb: gadget: f_uvc: fix superspeedplus transfer

[PATCH] usb: gadget: f_uvc: fix superspeedplus transfer

[3090101217]

From: Jing Leng <jleng@ambarella.com>

UVC driver doesn't set ssp_descriptors in struct usb_function,
If we use ssp UDC (e.g. cdnsp), UVC doesn't work.

Signed-off-by: Jing Leng <jleng@ambarella.com>
---
 drivers/usb/gadget/function/f_uvc.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index 71bb5e477dba..8fc9b035481e 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -478,6 +478,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	void *mem;
 
 	switch (speed) {
+	case USB_SPEED_SUPER_PLUS:
 	case USB_SPEED_SUPER:
 		uvc_control_desc = uvc->desc.ss_control;
 		uvc_streaming_cls = uvc->desc.ss_streaming;
@@ -521,7 +522,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	      + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
 	      + uvc_streaming_intf_alt0.bLength;
 
-	if (speed == USB_SPEED_SUPER) {
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS) {
 		bytes += uvc_ss_control_comp.bLength;
 		n_desc = 6;
 	} else {
@@ -565,7 +566,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
-	if (speed == USB_SPEED_SUPER)
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS)
 		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
@@ -727,6 +728,15 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 		}
 	}
 
+	if (gadget_is_superspeed_plus(c->cdev->gadget)) {
+		f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
+		if (IS_ERR(f->ssp_descriptors)) {
+			ret = PTR_ERR(f->ssp_descriptors);
+			f->ssp_descriptors = NULL;
+			goto error;
+		}
+	}
+
 	/* Preallocate control endpoint request. */
 	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 	uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
-- 
2.17.1

Re: [PATCH] usb: gadget: f_uvc: fix superspeedplus transfer

[Greg KH]

On Mon, Feb 14, 2022 at 01:52:24PM +0800, 3090101217@zju.edu.cn wrote:
> From: Jing Leng <jleng@ambarella.com>
> 
> UVC driver doesn't set ssp_descriptors in struct usb_function,
> If we use ssp UDC (e.g. cdnsp), UVC doesn't work.

I do not understand this text, sorry.  Please try to reword it to have
more descriptions.

thanks,

greg k-h

[PATCH v2] usb: gadget: f_uvc: fix superspeedplus transfer

[3090101217]

From: Jing Leng <jleng@ambarella.com>

UVC driver doesn't set ssp_descriptors in struct usb_function,
If UVC uses superspeedplus UDC (e.g. cdnsp), when
config_ep_by_speed_and_alt is called, the g->speed is
USB_SPEED_SUPER_PLUS, and f->ssp_descriptors is NULL,
So kernel will access NULL pointer of speed_desc.

Call trace:
 config_ep_by_speed_and_alt+0x3c/0x2a0 [libcomposite]
 uvc_function_set_alt+0xd4/0x2e8 [usb_f_uvc]
 set_config.constprop.0+0x154/0x3a0 [libcomposite]
 composite_setup+0x314/0xb44 [libcomposite]
 configfs_composite_setup+0x84/0xb0 [libcomposite]
 cdnsp_ep0_std_request+0x25c/0x470 [cdns3]
 cdnsp_setup_analyze+0x94/0x25c [cdns3]
 cdnsp_handle_event+0xe8/0x23c [cdns3]
 cdnsp_thread_irq_handler+0x58/0xe8 [cdns3]
 irq_thread_fn+0x2c/0xa0
 irq_thread+0x164/0x280
 kthread+0x128/0x134
 ret_from_fork+0x10/0x40

Signed-off-by: Jing Leng <jleng@ambarella.com>
---
 drivers/usb/gadget/function/f_uvc.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index 71bb5e477dba..8fc9b035481e 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -478,6 +478,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	void *mem;
 
 	switch (speed) {
+	case USB_SPEED_SUPER_PLUS:
 	case USB_SPEED_SUPER:
 		uvc_control_desc = uvc->desc.ss_control;
 		uvc_streaming_cls = uvc->desc.ss_streaming;
@@ -521,7 +522,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	      + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
 	      + uvc_streaming_intf_alt0.bLength;
 
-	if (speed == USB_SPEED_SUPER) {
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS) {
 		bytes += uvc_ss_control_comp.bLength;
 		n_desc = 6;
 	} else {
@@ -565,7 +566,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
-	if (speed == USB_SPEED_SUPER)
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS)
 		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
@@ -727,6 +728,15 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 		}
 	}
 
+	if (gadget_is_superspeed_plus(c->cdev->gadget)) {
+		f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
+		if (IS_ERR(f->ssp_descriptors)) {
+			ret = PTR_ERR(f->ssp_descriptors);
+			f->ssp_descriptors = NULL;
+			goto error;
+		}
+	}
+
 	/* Preallocate control endpoint request. */
 	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 	uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
-- 
2.17.1

Re: [PATCH v2] usb: gadget: f_uvc: fix superspeedplus transfer

[Greg KH]

On Tue, Feb 15, 2022 at 10:16:47AM +0800, 3090101217@zju.edu.cn wrote:
> From: Jing Leng <jleng@ambarella.com>
> 
> UVC driver doesn't set ssp_descriptors in struct usb_function,
> If UVC uses superspeedplus UDC (e.g. cdnsp), when
> config_ep_by_speed_and_alt is called, the g->speed is
> USB_SPEED_SUPER_PLUS, and f->ssp_descriptors is NULL,
> So kernel will access NULL pointer of speed_desc.
> 
> Call trace:
>  config_ep_by_speed_and_alt+0x3c/0x2a0 [libcomposite]
>  uvc_function_set_alt+0xd4/0x2e8 [usb_f_uvc]
>  set_config.constprop.0+0x154/0x3a0 [libcomposite]
>  composite_setup+0x314/0xb44 [libcomposite]
>  configfs_composite_setup+0x84/0xb0 [libcomposite]
>  cdnsp_ep0_std_request+0x25c/0x470 [cdns3]
>  cdnsp_setup_analyze+0x94/0x25c [cdns3]
>  cdnsp_handle_event+0xe8/0x23c [cdns3]
>  cdnsp_thread_irq_handler+0x58/0xe8 [cdns3]
>  irq_thread_fn+0x2c/0xa0
>  irq_thread+0x164/0x280
>  kthread+0x128/0x134
>  ret_from_fork+0x10/0x40

What does "call trace" here mean?  Is this an error?  Something else?

> 
> Signed-off-by: Jing Leng <jleng@ambarella.com>
> ---
>  drivers/usb/gadget/function/f_uvc.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)

You did not read the information that my bot told you to read, for how
to properly version your patches :(

Please go back and do so when you resend all of them.

Also this is not a patch series?  Why not?

thanks,

greg k-h

Re: [PATCH v2] usb: gadget: f_uvc: fix superspeedplus transfer

[冷静]

Hi Greg KH,

Sorry for the trouble, as a new contributor to kernel.
Although I have readed the document that how to submit patches,
I'm still missing some details.

> What does "call trace" here mean?  Is this an error?  Something else?
It is "call trace" when the kernel accessed NULL pointer and handed.

> You did not read the information that my bot told you to read, for how
> to properly version your patches :(
> 
> Please go back and do so when you resend all of them.
> 
> Also this is not a patch series?  Why not?

I readed the bot told, but I still missed it.
The new patch only adds more detailed patch description.
So it is not a patch series.

thanks,

Jing Leng

Re: [PATCH v2] usb: gadget: f_uvc: fix superspeedplus transfer

[Greg KH]

On Wed, Feb 16, 2022 at 10:34:00AM +0800, 冷静 wrote:
> Hi Greg KH,
> 
> Sorry for the trouble, as a new contributor to kernel.

That's fine, maybe get some more experience first before trying to add
new features?  Try doing some coding style cleanups in drivers/staging/
or reviewing other people's code submissions first.  That way you can
learn how things work easier.

> Although I have readed the document that how to submit patches,
> I'm still missing some details.
> 
> > What does "call trace" here mean?  Is this an error?  Something else?
> It is "call trace" when the kernel accessed NULL pointer and handed.

I do not understand this, sorry.

> > You did not read the information that my bot told you to read, for how
> > to properly version your patches :(
> > 
> > Please go back and do so when you resend all of them.
> > 
> > Also this is not a patch series?  Why not?
> 
> I readed the bot told, but I still missed it.
> The new patch only adds more detailed patch description.
> So it is not a patch series.

I asked you to make it a patch series.

thanks,

greg k-h

Re: [PATCH v2] usb: gadget: f_uvc: fix superspeedplus transfer

[Jing Leng]

Hi Greg KH,

Sorry for the confusion.

I tested the feature on linux-5.10, it will cause Oops.
The Oops is as follows:
 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
 Mem abort info:
   ESR = 0x96000005
   EC = 0x25: DABT (current EL), IL = 32 bits
   SET = 0, FnV = 0
   EA = 0, S1PTW = 0
 Data abort info:
   ISV = 0, ISS = 0x00000005
   CM = 0, WnR = 0
 user pgtable: 4k pages, 39-bit VAs, pgdp=00000001b12cf000
 [0000000000000000] pgd=0000000000000000, p4d=0000000000000000, pud=0000000000000000
 Internal error: Oops: 96000005 [#1] PREEMPT SMP
 Modules linked in: ...
 CPU: 0 PID: 619 Comm: irq/95-20200080 Tainted: G           O      5.10.61 #2
 Hardware name: Ambarella CV5 TIMN Board (DT)
 pstate: 20c00085 (nzCv daIf +PAN +UAO -TCO BTYPE=--)
 pc : config_ep_by_speed_and_alt+0x3c/0x2a0 [libcomposite]
 lr : config_ep_by_speed+0x14/0x20 [libcomposite]
 sp : ffffffc011dbbac0
 x29: ffffffc011dbbac0 x28: 0000000000000001
 x27: ffffff81b3eb1920 x26: 0000000000000000
 x25: ffffff81b68085e8 x24: ffffff81b3ee4c00
 x23: ffffff81b3d71c40 x22: 0000000000000000
 x21: 0000000000000000 x20: ffffff81b68085e8
 x19: ffffff81b6808000 x18: ffffffc091dbb737
 x17: 0000000000000017 x16: 000000000000000a
 x15: 0000000000000006 x14: ffffffc011dbb73f
 x13: 0000000000000001 x12: ffffffc0109c97e8
 x11: 0000000000000652 x10: 00000000000e5a65
 x9 : ffffffc0109c97e8 x8 : 00000000fffff7ff
 x7 : 00000000000017fd x6 : 0000000000000001
 x5 : ffffff81fb5976a8 x4 : 0000000000000006
 x3 : 0000000000000000 x2 : ffffff81b6838718
 x1 : 0000000000000000 x0 : ffffff81b6838008
 Call trace:
  config_ep_by_speed_and_alt+0x3c/0x2a0 [libcomposite]
  uvc_function_set_alt+0xd4/0x2e8 [usb_f_uvc]
  set_config.constprop.0+0x154/0x3a0 [libcomposite]
  composite_setup+0x314/0xb44 [libcomposite]
  configfs_composite_setup+0x84/0xb0 [libcomposite]
  cdnsp_ep0_std_request+0x25c/0x470 [cdns3]
  cdnsp_setup_analyze+0x94/0x25c [cdns3]
  cdnsp_handle_event+0xe8/0x23c [cdns3]
  cdnsp_thread_irq_handler+0x58/0xe8 [cdns3]
  irq_thread_fn+0x2c/0xa0
  irq_thread+0x164/0x280
  kthread+0x128/0x134
  ret_from_fork+0x10/0x40
 Code: 71000c9f 54000b60 f9400821 52800006 (f9400024)
 ---[ end trace 7d3065b8181de7a6 ]---
 note: irq/95-20200080[619] exited with preempt_count 2
 genirq: exiting task "irq/95-20200080" (619) is an active IRQ thread (irq 95)

But the Oops is fixed in the latest kernel by the following commit:
 commit 16d42759207fc3d1bff7cfd330a08a225e470ba0
 Author: Qihang Hu <huqihang@oppo.com>
 Date:   Wed Nov 10 18:11:29 2021 +0800

     usb: gadget: composite: Show warning if function driver's descriptors are incomplete.

There are some problems with my previous understanding,
so the patch is a feature but not a bug, I will modify the
title and description of the patch and resend it. 

Thanks
Jing Leng

[PATCH v3] usb: gadget: f_uvc: add superspeed plus transfer support

[3090101217]

From: Jing Leng <jleng@ambarella.com>

UVC driver doesn't set ssp_descriptors in struct usb_function,
it doesn't support USB_SPEED_SUPER_PLUS transfer. So we can
refer to USB_SPEED_SUPER to realize the support of
USB_SPEED_SUPER_PLUS.

If users use a USB device controller that speed can be up to
USB_SPEED_SUPER_PLUS (10 Gbps), downgrading to USB_SPEED_SUPER
(5 Gbps) is not a good performance. In addition, it triggers a
warning "configfs-gadget gadget: uvc doesn't hold the descriptors
for current speed".

Signed-off-by: Jing Leng <jleng@ambarella.com>
---
ChangeLog v2->v3:
- Modify the title and description of the PATCH
- It is a feature but not a bug
ChangeLog v1->v2:
- Update more detailed description of the PATCH
---
 drivers/usb/gadget/function/f_uvc.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index 71bb5e477dba..8fc9b035481e 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -478,6 +478,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	void *mem;
 
 	switch (speed) {
+	case USB_SPEED_SUPER_PLUS:
 	case USB_SPEED_SUPER:
 		uvc_control_desc = uvc->desc.ss_control;
 		uvc_streaming_cls = uvc->desc.ss_streaming;
@@ -521,7 +522,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	      + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
 	      + uvc_streaming_intf_alt0.bLength;
 
-	if (speed == USB_SPEED_SUPER) {
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS) {
 		bytes += uvc_ss_control_comp.bLength;
 		n_desc = 6;
 	} else {
@@ -565,7 +566,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
-	if (speed == USB_SPEED_SUPER)
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS)
 		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
@@ -727,6 +728,15 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 		}
 	}
 
+	if (gadget_is_superspeed_plus(c->cdev->gadget)) {
+		f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
+		if (IS_ERR(f->ssp_descriptors)) {
+			ret = PTR_ERR(f->ssp_descriptors);
+			f->ssp_descriptors = NULL;
+			goto error;
+		}
+	}
+
 	/* Preallocate control endpoint request. */
 	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 	uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
-- 
2.17.1

[PATCH v4] usb: gadget: f_uvc: add super speed plus transfer support

[Jing Leng]

UVC driver doesn't set ssp_descriptors in struct usb_function,
it doesn't support USB_SPEED_SUPER_PLUS transfer. So we can
refer to USB_SPEED_SUPER to realize the support of
USB_SPEED_SUPER_PLUS.

If users use a USB device controller that speed can be up to
USB_SPEED_SUPER_PLUS (10 Gbps), downgrading to USB_SPEED_SUPER
(5 Gbps) is not a good performance. In addition, it triggers a
warning "configfs-gadget gadget: uvc doesn't hold the descriptors
for current speed".

Signed-off-by: Jing Leng <jleng@ambarella.com>
---
ChangeLog v3->v4:
- Rebase the patch.
- Make email addresses ('From' and 'Signed-off-by') consistent.
ChangeLog v2->v3:
- Modify the title and description of the PATCH
- It is a feature but not a bug
ChangeLog v1->v2:
- Update more detailed description of the PATCH
---
 drivers/usb/gadget/function/f_uvc.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index 6e196e06181e..6ffaf594be9d 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -482,6 +482,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	void *mem;
 
 	switch (speed) {
+	case USB_SPEED_SUPER_PLUS:
 	case USB_SPEED_SUPER:
 		uvc_control_desc = uvc->desc.ss_control;
 		uvc_streaming_cls = uvc->desc.ss_streaming;
@@ -526,7 +527,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	      + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
 	      + uvc_streaming_intf_alt0.bLength;
 
-	if (speed == USB_SPEED_SUPER) {
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS) {
 		bytes += uvc_ss_control_comp.bLength;
 		n_desc = 6;
 	} else {
@@ -570,7 +571,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
 	uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
-	if (speed == USB_SPEED_SUPER)
+	if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS)
 		UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
 
 	UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep);
@@ -733,6 +734,15 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 		}
 	}
 
+	if (gadget_is_superspeed_plus(c->cdev->gadget)) {
+		f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
+		if (IS_ERR(f->ssp_descriptors)) {
+			ret = PTR_ERR(f->ssp_descriptors);
+			f->ssp_descriptors = NULL;
+			goto error;
+		}
+	}
+
 	/* Preallocate control endpoint request. */
 	uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
 	uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
-- 
2.17.1


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RE: [EXT] Re: [PATCH v4] usb: gadget: f_uvc: add super speed plus transfer support

[Jing Leng]

Hi Kieran,

The patch is everthing that is required to support USB_SPEED_SUPER_PLUS.

I don't have a way to disabling this trailing legal statement when sending emails, it is automatically added by Ambarella mail server, not added by me.
Ambarella follows the GPLv2 protocol when submitting any linux kernel patches to the Linux community.

Thanks!

-----Original Message-----
From: Kieran Bingham <kieran.bingham@ideasonboard.com> 
Sent: Thursday, November 3, 2022 6:05 PM
To: Jing Leng <jleng@ambarella.com>; balbi@kernel.org; gregkh@linuxfoundation.org; laurent.pinchart@ideasonboard.com
Cc: linux-kernel@vger.kernel.org; linux-usb@vger.kernel.org; Jing Leng <jleng@ambarella.com>; Dan Scally <dan.scally@ideasonboard.com>
Subject: [EXT] Re: [PATCH v4] usb: gadget: f_uvc: add super speed plus transfer support

Hi Jing,

Quoting Jing Leng (2022-11-03 06:00:41)
> UVC driver doesn't set ssp_descriptors in struct usb_function, it 
> doesn't support USB_SPEED_SUPER_PLUS transfer. So we can refer to 
> USB_SPEED_SUPER to realize the support of USB_SPEED_SUPER_PLUS.

This is a bit confusing to read. Do you mean that we should (later?) add more functionality to support USB_SPEED_SUPER_PLUS? Or is this everthing that is required ?

> If users use a USB device controller that speed can be up to 
> USB_SPEED_SUPER_PLUS (10 Gbps), downgrading to USB_SPEED_SUPER
> (5 Gbps) is not a good performance. In addition, it triggers a warning 
> "configfs-gadget gadget: uvc doesn't hold the descriptors for current 
> speed".
> 
> Signed-off-by: Jing Leng <jleng@ambarella.com>
> ---
> ChangeLog v3->v4:
> - Rebase the patch.
> - Make email addresses ('From' and 'Signed-off-by') consistent.
> ChangeLog v2->v3:
> - Modify the title and description of the PATCH
> - It is a feature but not a bug
> ChangeLog v1->v2:
> - Update more detailed description of the PATCH
> ---
>  drivers/usb/gadget/function/f_uvc.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/gadget/function/f_uvc.c 
> b/drivers/usb/gadget/function/f_uvc.c
> index 6e196e06181e..6ffaf594be9d 100644
> --- a/drivers/usb/gadget/function/f_uvc.c
> +++ b/drivers/usb/gadget/function/f_uvc.c
> @@ -482,6 +482,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
>         void *mem;
>  
>         switch (speed) {
> +       case USB_SPEED_SUPER_PLUS:
>         case USB_SPEED_SUPER:
>                 uvc_control_desc = uvc->desc.ss_control;
>                 uvc_streaming_cls = uvc->desc.ss_streaming; @@ -526,7 
> +527,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
>               + uvc_control_ep.bLength + uvc_control_cs_ep.bLength
>               + uvc_streaming_intf_alt0.bLength;
>  
> -       if (speed == USB_SPEED_SUPER) {
> +       if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS) 
> + {
>                 bytes += uvc_ss_control_comp.bLength;
>                 n_desc = 6;
>         } else {
> @@ -570,7 +571,7 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
>         uvc_control_header->baInterfaceNr[0] = uvc->streaming_intf;
>  
>         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_ep);
> -       if (speed == USB_SPEED_SUPER)
> +       if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS)
>                 UVC_COPY_DESCRIPTOR(mem, dst, &uvc_ss_control_comp);
>  
>         UVC_COPY_DESCRIPTOR(mem, dst, &uvc_control_cs_ep); @@ -733,6 
> +734,15 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
>                 }
>         }
>  
> +       if (gadget_is_superspeed_plus(c->cdev->gadget)) {
> +               f->ssp_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER_PLUS);
> +               if (IS_ERR(f->ssp_descriptors)) {
> +                       ret = PTR_ERR(f->ssp_descriptors);
> +                       f->ssp_descriptors = NULL;
> +                       goto error;
> +               }
> +       }
> +
>         /* Preallocate control endpoint request. */
>         uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
>         uvc->control_buf = kmalloc(UVC_MAX_REQUEST_SIZE, GFP_KERNEL);
> --
> 2.17.1
> 
> 
> **********************************************************************
> This email and attachments contain Ambarella Proprietary and/or Confidential Information and is intended solely for the use of the individual(s) to whom it is addressed. Any unauthorized review, use, disclosure, distribute, copy, or print is prohibited. If you are not an intended recipient, please contact the sender by reply email and destroy all copies of the original message. Thank you.

Do you have a way to disabling this trailing legal statement when sending emails?

It's really not appropriate for sending to public mailinglists, and if you are really asserting that this patch is confidential and proprietary
- then it probably can't be integrated into the kernel ...

--
Kieran

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Re: [PATCH v4] usb: gadget: f_uvc: add super speed plus transfer support

[Greg KH]

On Thu, Nov 03, 2022 at 02:00:41PM +0800, Jing Leng wrote:
> **********************************************************************
> This email and attachments contain Ambarella Proprietary and/or Confidential Information and is intended solely for the use of the individual(s) to whom it is addressed. Any unauthorized review, use, disclosure, distribute, copy, or print is prohibited. If you are not an intended recipient, please contact the sender by reply email and destroy all copies of the original message. Thank you.

Now deleted, sorry.

greg k-h