>> Thanks, that seems to work! (Judging by the absence of my original
>> issue with the xum1541 adapter; I haven't checked what's actually
>> happening on the bus).
>>
>> Martin
>>
>
> Great, thanks.
>
> Now this test code needs to be cleaned up a turned into a real patch
Can you test one more round?
The code below is cleaned up but it also has a functional change.
This version issues separate commands for dropping and adding endpoints.
Previous code both did all on one command.
If it works I'll send it forward.
Thanks
-Mathias
---
From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Subject: [PATCH] usb: Fix out of sync data toggle if a configured device is
reconfigured
Userspace drivers that use a SetConfiguration() request to "lightweight"
reset a already configured usb device might cause data toggles to get out
of sync between the device and host, and the device becomes unusable.
The xHCI host requires endpoints to be dropped and added back to reset the
toggle. USB core avoids these otherwise extra steps if the current active
configuration is the same as the new requested configuration.
A SetConfiguration() request will reset the device side data toggles.
Make sure usb core drops and adds back the endpoints in this case.
To avoid code duplication split the current usb_disable_device() function
and reuse the endpoint specific part.
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/core/message.c | 89 +++++++++++++++++---------------------
1 file changed, 40 insertions(+), 49 deletions(-)
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index 6197938dcc2d..46c0d5f633a7 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1205,6 +1205,35 @@ void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf,
}
}
+/*
+ * usb_disable_device_endpoints -- Disable all endpoints for a device
+ * @dev: the device whose endpoints are being disabled
+ * @skip_ep0: 0 to disable endpoint 0, 1 to skip it.
+ */
+static void usb_disable_device_endpoints(struct usb_device *dev, int skip_ep0)
+{
+ struct usb_hcd *hcd = bus_to_hcd(dev->bus);
+ int i;
+
+ if (hcd->driver->check_bandwidth) {
+
+ /* First pass: Cancel URBs, leave endpoint pointers intact. */
+ for (i = skip_ep0; i < 16; ++i) {
+ usb_disable_endpoint(dev, i, false);
+ usb_disable_endpoint(dev, i + USB_DIR_IN, false);
+ }
+ /* Remove endpoints from the host controller internal state */
+ mutex_lock(hcd->bandwidth_mutex);
+ usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
+ mutex_unlock(hcd->bandwidth_mutex);
+ }
+ /* Second pass: remove endpoint pointers */
+ for (i = skip_ep0; i < 16; ++i) {
+ usb_disable_endpoint(dev, i, true);
+ usb_disable_endpoint(dev, i + USB_DIR_IN, true);
+ }
+}
+
/**
* usb_disable_device - Disable all the endpoints for a USB device
* @dev: the device whose endpoints are being disabled
@@ -1218,7 +1247,6 @@ void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf,
void usb_disable_device(struct usb_device *dev, int skip_ep0)
{
int i;
- struct usb_hcd *hcd = bus_to_hcd(dev->bus);
/* getting rid of interfaces will disconnect
* any drivers bound to them (a key side effect)
@@ -1264,22 +1292,8 @@ void usb_disable_device(struct usb_device *dev, int skip_ep0)
dev_dbg(&dev->dev, "%s nuking %s URBs\n", __func__,
skip_ep0 ? "non-ep0" : "all");
- if (hcd->driver->check_bandwidth) {
- /* First pass: Cancel URBs, leave endpoint pointers intact. */
- for (i = skip_ep0; i < 16; ++i) {
- usb_disable_endpoint(dev, i, false);
- usb_disable_endpoint(dev, i + USB_DIR_IN, false);
- }
- /* Remove endpoints from the host controller internal state */
- mutex_lock(hcd->bandwidth_mutex);
- usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
- mutex_unlock(hcd->bandwidth_mutex);
- /* Second pass: remove endpoint pointers */
- }
- for (i = skip_ep0; i < 16; ++i) {
- usb_disable_endpoint(dev, i, true);
- usb_disable_endpoint(dev, i + USB_DIR_IN, true);
- }
+
+ usb_disable_device_endpoints(dev, skip_ep0);
}
/**
@@ -1537,10 +1551,7 @@ int usb_reset_configuration(struct usb_device *dev)
* calls during probe() are fine
*/
- for (i = 1; i < 16; ++i) {
- usb_disable_endpoint(dev, i, true);
- usb_disable_endpoint(dev, i + USB_DIR_IN, true);
- }
+ usb_disable_device_endpoints(dev, 1); /* skip ep0*/
config = dev->actconfig;
retval = 0;
@@ -1553,34 +1564,10 @@ int usb_reset_configuration(struct usb_device *dev)
mutex_unlock(hcd->bandwidth_mutex);
return -ENOMEM;
}
- /* Make sure we have enough bandwidth for each alternate setting 0 */
- for (i = 0; i < config->desc.bNumInterfaces; i++) {
- struct usb_interface *intf = config->interface[i];
- struct usb_host_interface *alt;
- alt = usb_altnum_to_altsetting(intf, 0);
- if (!alt)
- alt = &intf->altsetting[0];
- if (alt != intf->cur_altsetting)
- retval = usb_hcd_alloc_bandwidth(dev, NULL,
- intf->cur_altsetting, alt);
- if (retval < 0)
- break;
- }
- /* If not, reinstate the old alternate settings */
+ /* xHCI adds all endpoints in usb_hcd_alloc_bandwidth */
+ retval = usb_hcd_alloc_bandwidth(dev, config, NULL, NULL);
if (retval < 0) {
-reset_old_alts:
- for (i--; i >= 0; i--) {
- struct usb_interface *intf = config->interface[i];
- struct usb_host_interface *alt;
-
- alt = usb_altnum_to_altsetting(intf, 0);
- if (!alt)
- alt = &intf->altsetting[0];
- if (alt != intf->cur_altsetting)
- usb_hcd_alloc_bandwidth(dev, NULL,
- alt, intf->cur_altsetting);
- }
usb_enable_lpm(dev);
mutex_unlock(hcd->bandwidth_mutex);
return retval;
@@ -1589,8 +1576,12 @@ int usb_reset_configuration(struct usb_device *dev)
USB_REQ_SET_CONFIGURATION, 0,
config->desc.bConfigurationValue, 0,
NULL, 0, USB_CTRL_SET_TIMEOUT);
- if (retval < 0)
- goto reset_old_alts;
+ if (retval < 0) {
+ retval = usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
+ usb_enable_lpm(dev);
+ mutex_unlock(hcd->bandwidth_mutex);
+ return retval;
+ }
mutex_unlock(hcd->bandwidth_mutex);
/* re-init hc/hcd interface/endpoint state */
--
2.17.1
