diff mbox series

[v9,1/2] usb: hub : Add devaddr in struct usb_device

Message ID 1557491070-24715-2-git-send-email-jilin@nvidia.com (mailing list archive)
State Superseded
Headers show
Series usb: xhci: Add Clear_TT_Buffer | expand

Commit Message

Jim Lin May 10, 2019, 12:24 p.m. UTC
The Clear_TT_Buffer request sent to the hub includes the address of
the LS/FS child device in wValue field. usb_hub_clear_tt_buffer()
uses udev->devnum to set the address wValue. This won't work for
devices connected to xHC.

For other host controllers udev->devnum is the same as the address of
the usb device, chosen and set by usb core. With xHC the controller
hardware assigns the address, and won't be the same as devnum.

Here we add devaddr in "struct usb_device" for
usb_hub_clear_tt_buffer() to use.

Signed-off-by: Jim Lin <jilin@nvidia.com>
---
v2: xhci_clear_tt_buffer_complete: add static, shorter indentation
    , remove its claiming in xhci.h
v3: Add description for clearing_tt (xhci.h)
v4: Remove clearing_tt flag because hub_tt_work has hub->tt.lock
    to protect for Clear_TT_Buffer to be run serially.
    Remove xhci_clear_tt_buffer_complete as it's not necessary.
    Same reason as the above.
    Extend usb_hub_clear_tt_buffer parameter
v5: Not extending usb_hub_clear_tt_buffer parameter
    Add description.
v6: Remove unused parameter slot_id from xhci_clear_hub_tt_buffer
v7: Add devaddr field in "struct usb_device"
v8: split as two patches, change type from int to u8 for devaddr.
v9: Use pahole to find place to put devaddr in struct usb_device.
    Remove space between type cast and variable.
    hub.c changed from v8
    clear->devinfo |= (u16) (udev->devaddr << 4);
    to 
    clear->devinfo |= ((u16)udev->devaddr) << 4;
    to solve a problem if devaddr is larger than 16.


 drivers/usb/core/hub.c | 4 +++-
 include/linux/usb.h    | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

Comments

Alan Stern May 10, 2019, 2:19 p.m. UTC | #1
On Fri, 10 May 2019, Jim Lin wrote:

> The Clear_TT_Buffer request sent to the hub includes the address of
> the LS/FS child device in wValue field. usb_hub_clear_tt_buffer()
> uses udev->devnum to set the address wValue. This won't work for
> devices connected to xHC.
> 
> For other host controllers udev->devnum is the same as the address of
> the usb device, chosen and set by usb core. With xHC the controller
> hardware assigns the address, and won't be the same as devnum.
> 
> Here we add devaddr in "struct usb_device" for
> usb_hub_clear_tt_buffer() to use.
> 
> Signed-off-by: Jim Lin <jilin@nvidia.com>
> ---
> v2: xhci_clear_tt_buffer_complete: add static, shorter indentation
>     , remove its claiming in xhci.h
> v3: Add description for clearing_tt (xhci.h)
> v4: Remove clearing_tt flag because hub_tt_work has hub->tt.lock
>     to protect for Clear_TT_Buffer to be run serially.
>     Remove xhci_clear_tt_buffer_complete as it's not necessary.
>     Same reason as the above.
>     Extend usb_hub_clear_tt_buffer parameter
> v5: Not extending usb_hub_clear_tt_buffer parameter
>     Add description.
> v6: Remove unused parameter slot_id from xhci_clear_hub_tt_buffer
> v7: Add devaddr field in "struct usb_device"
> v8: split as two patches, change type from int to u8 for devaddr.
> v9: Use pahole to find place to put devaddr in struct usb_device.
>     Remove space between type cast and variable.
>     hub.c changed from v8
>     clear->devinfo |= (u16) (udev->devaddr << 4);
>     to 
>     clear->devinfo |= ((u16)udev->devaddr) << 4;
>     to solve a problem if devaddr is larger than 16.
> 
> 
>  drivers/usb/core/hub.c | 4 +++-
>  include/linux/usb.h    | 2 ++
>  2 files changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index 15a2934dc29d..0d4b289be103 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -873,7 +873,7 @@ int usb_hub_clear_tt_buffer(struct urb *urb)
>  	/* info that CLEAR_TT_BUFFER needs */
>  	clear->tt = tt->multi ? udev->ttport : 1;
>  	clear->devinfo = usb_pipeendpoint (pipe);
> -	clear->devinfo |= udev->devnum << 4;
> +	clear->devinfo |= ((u16)udev->devaddr) << 4;
>  	clear->devinfo |= usb_pipecontrol(pipe)
>  			? (USB_ENDPOINT_XFER_CONTROL << 11)
>  			: (USB_ENDPOINT_XFER_BULK << 11);
> @@ -2125,6 +2125,8 @@ static void update_devnum(struct usb_device *udev, int devnum)
>  	/* The address for a WUSB device is managed by wusbcore. */
>  	if (!udev->wusb)
>  		udev->devnum = devnum;
> +	if (!udev->devaddr)
> +		udev->devaddr = (u8)devnum;

Whether or not to put a space after the ')' in a typecast is a matter 
of personal choice; CodingStyle doesn't say anything about it.  Quite 
often the space is present.  IIRC, that is how K&R does it.  But it 
doesn't really matter.

>  }
>  
>  static void hub_free_dev(struct usb_device *udev)
> diff --git a/include/linux/usb.h b/include/linux/usb.h
> index 4229eb74bd2c..5641965e44a1 100644
> --- a/include/linux/usb.h
> +++ b/include/linux/usb.h
> @@ -566,6 +566,7 @@ struct usb3_lpm_parameters {
>   * @tt: Transaction Translator info; used with low/full speed dev, highspeed hub
>   * @ttport: device port on that tt hub
>   * @toggle: one bit for each endpoint, with ([0] = IN, [1] = OUT) endpoints
> + * @devaddr: device address, XHCI: assigned by HW, others: same as devnum
>   * @parent: our hub, unless we're the root
>   * @bus: bus we're part of
>   * @ep0: endpoint 0 data (default control pipe)
> @@ -643,6 +644,7 @@ struct usb_device {
>  	int		ttport;
>  
>  	unsigned int toggle[2];
> +	u8 devaddr;

This is another lousy place to put the new value.  A much better
position would be immediately after "u8 level".

>  	struct usb_device *parent;
>  	struct usb_bus *bus;

You should move into this patch the code added to xhci.c to assign
udev->devaddr.  Without it, this patch is incomplete: devaddr will not
contain the correct value for devices on a USB-3 bus.  And it doesn't
belong in the 2/2 patch -- that patch is all about making xhci-hcd call
usb_clear_tt_buffer().

Alan Stern
diff mbox series

Patch

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 15a2934dc29d..0d4b289be103 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -873,7 +873,7 @@  int usb_hub_clear_tt_buffer(struct urb *urb)
 	/* info that CLEAR_TT_BUFFER needs */
 	clear->tt = tt->multi ? udev->ttport : 1;
 	clear->devinfo = usb_pipeendpoint (pipe);
-	clear->devinfo |= udev->devnum << 4;
+	clear->devinfo |= ((u16)udev->devaddr) << 4;
 	clear->devinfo |= usb_pipecontrol(pipe)
 			? (USB_ENDPOINT_XFER_CONTROL << 11)
 			: (USB_ENDPOINT_XFER_BULK << 11);
@@ -2125,6 +2125,8 @@  static void update_devnum(struct usb_device *udev, int devnum)
 	/* The address for a WUSB device is managed by wusbcore. */
 	if (!udev->wusb)
 		udev->devnum = devnum;
+	if (!udev->devaddr)
+		udev->devaddr = (u8)devnum;
 }
 
 static void hub_free_dev(struct usb_device *udev)
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 4229eb74bd2c..5641965e44a1 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -566,6 +566,7 @@  struct usb3_lpm_parameters {
  * @tt: Transaction Translator info; used with low/full speed dev, highspeed hub
  * @ttport: device port on that tt hub
  * @toggle: one bit for each endpoint, with ([0] = IN, [1] = OUT) endpoints
+ * @devaddr: device address, XHCI: assigned by HW, others: same as devnum
  * @parent: our hub, unless we're the root
  * @bus: bus we're part of
  * @ep0: endpoint 0 data (default control pipe)
@@ -643,6 +644,7 @@  struct usb_device {
 	int		ttport;
 
 	unsigned int toggle[2];
+	u8 devaddr;
 
 	struct usb_device *parent;
 	struct usb_bus *bus;