* [PATCH v7 2/3] USB: Better name for __check_usb_generic()
2020-08-04 11:38 [PATCH v7 1/3] USB: Also check for ->match Bastien Nocera
@ 2020-08-04 11:38 ` Bastien Nocera
2020-08-04 11:38 ` [PATCH v7 3/3] USB: Fix device driver race Bastien Nocera
2020-08-18 9:00 ` [PATCH v7 1/3] USB: Also check for ->match Greg Kroah-Hartman
2 siblings, 0 replies; 6+ messages in thread
From: Bastien Nocera @ 2020-08-04 11:38 UTC (permalink / raw)
To: linux-usb; +Cc: Greg Kroah-Hartman, Alan Stern, Bastien Nocera
__check_usb_generic() doesn't explain very well what the
function actually does: It checks to see whether the driver is
non-generic and matches the device.
Change it to check_for_non_generic_match()
Signed-off-by: Bastien Nocera <hadess@hadess.net>
---
First version based on Alan's comment:
https://marc.info/?l=linux-usb&m=159568870400795&w=2
drivers/usb/core/generic.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c
index 2b2f1ab6e36a..22c887f5c497 100644
--- a/drivers/usb/core/generic.c
+++ b/drivers/usb/core/generic.c
@@ -195,7 +195,7 @@ int usb_choose_configuration(struct usb_device *udev)
}
EXPORT_SYMBOL_GPL(usb_choose_configuration);
-static int __check_usb_generic(struct device_driver *drv, void *data)
+static int __check_for_non_generic_match(struct device_driver *drv, void *data)
{
struct usb_device *udev = data;
struct usb_device_driver *udrv;
@@ -219,7 +219,7 @@ static bool usb_generic_driver_match(struct usb_device *udev)
* If any other driver wants the device, leave the device to this other
* driver.
*/
- if (bus_for_each_drv(&usb_bus_type, NULL, udev, __check_usb_generic))
+ if (bus_for_each_drv(&usb_bus_type, NULL, udev, __check_for_non_generic_match))
return false;
return true;
--
2.26.2
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v7 3/3] USB: Fix device driver race
2020-08-04 11:38 [PATCH v7 1/3] USB: Also check for ->match Bastien Nocera
2020-08-04 11:38 ` [PATCH v7 2/3] USB: Better name for __check_usb_generic() Bastien Nocera
@ 2020-08-04 11:38 ` Bastien Nocera
2020-08-18 9:00 ` [PATCH v7 1/3] USB: Also check for ->match Greg Kroah-Hartman
2 siblings, 0 replies; 6+ messages in thread
From: Bastien Nocera @ 2020-08-04 11:38 UTC (permalink / raw)
To: linux-usb; +Cc: Greg Kroah-Hartman, Alan Stern, Bastien Nocera
When a new device with a specialised device driver is plugged in, the
new driver will be modprobe()'d but the driver core will attach the
"generic" driver to the device.
After that, nothing will trigger a reprobe when the modprobe()'d device
driver has finished initialising, as the device has the "generic"
driver attached to it.
Trigger a reprobe ourselves when new specialised drivers get registered.
Fixes: 88b7381a939d ("USB: Select better matching USB drivers when available")
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
---
Changes since v6:
- Added Alan's ack
Changes since v5:
- Throw error when device_reprobe() fails
Changes since v4:
- Add commit subject to "fixes" section
- Clarify conditional that checks for generic driver
- Remove check duplicated inside the loop
Changes since v3:
- Only reprobe devices that could use the new driver
- Many code fixes
Changes since v2:
- Fix formatting
Changes since v1:
- Simplified after Alan Stern's comments and some clarifications from
Benjamin Tissoires.
drivers/usb/core/driver.c | 40 +++++++++++++++++++++++++++++++++++++--
1 file changed, 38 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index f81606c6a35b..7e73e989645b 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -905,6 +905,35 @@ static int usb_uevent(struct device *dev, struct kobj_uevent_env *env)
return 0;
}
+static bool is_dev_usb_generic_driver(struct device *dev)
+{
+ struct usb_device_driver *udd = dev->driver ?
+ to_usb_device_driver(dev->driver) : NULL;
+
+ return udd == &usb_generic_driver;
+}
+
+static int __usb_bus_reprobe_drivers(struct device *dev, void *data)
+{
+ struct usb_device_driver *new_udriver = data;
+ struct usb_device *udev;
+ int ret;
+
+ if (!is_dev_usb_generic_driver(dev))
+ return 0;
+
+ udev = to_usb_device(dev);
+ if (usb_device_match_id(udev, new_udriver->id_table) == NULL &&
+ (!new_udriver->match || new_udriver->match(udev) != 0))
+ return 0;
+
+ ret = device_reprobe(dev);
+ if (ret && ret != -EPROBE_DEFER)
+ dev_err(dev, "Failed to reprobe device (error %d)\n", ret);
+
+ return 0;
+}
+
/**
* usb_register_device_driver - register a USB device (not interface) driver
* @new_udriver: USB operations for the device driver
@@ -934,13 +963,20 @@ int usb_register_device_driver(struct usb_device_driver *new_udriver,
retval = driver_register(&new_udriver->drvwrap.driver);
- if (!retval)
+ if (!retval) {
pr_info("%s: registered new device driver %s\n",
usbcore_name, new_udriver->name);
- else
+ /*
+ * Check whether any device could be better served with
+ * this new driver
+ */
+ bus_for_each_dev(&usb_bus_type, NULL, new_udriver,
+ __usb_bus_reprobe_drivers);
+ } else {
printk(KERN_ERR "%s: error %d registering device "
" driver %s\n",
usbcore_name, retval, new_udriver->name);
+ }
return retval;
}
--
2.26.2
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v7 1/3] USB: Also check for ->match
2020-08-04 11:38 [PATCH v7 1/3] USB: Also check for ->match Bastien Nocera
2020-08-04 11:38 ` [PATCH v7 2/3] USB: Better name for __check_usb_generic() Bastien Nocera
2020-08-04 11:38 ` [PATCH v7 3/3] USB: Fix device driver race Bastien Nocera
@ 2020-08-18 9:00 ` Greg Kroah-Hartman
2020-08-18 9:42 ` Bastien Nocera
2 siblings, 1 reply; 6+ messages in thread
From: Greg Kroah-Hartman @ 2020-08-18 9:00 UTC (permalink / raw)
To: Bastien Nocera; +Cc: linux-usb, Alan Stern
On Tue, Aug 04, 2020 at 01:38:32PM +0200, Bastien Nocera wrote:
> We only ever used the ID table matching before, but we should probably
> also support an open-coded match function.
>
> Fixes: 88b7381a939de ("USB: Select better matching USB drivers when available")
> Signed-off-by: Bastien Nocera <hadess@hadess.net>
> Acked-by: Alan Stern <stern@rowland.harvard.edu>
The subject line does not make sense, what is "also"? Who is doing
this?
Coming back to this after a week I have no idea what is going on, so
that's a sign that it needs to be reworded :(
thanks,
greg k-h
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v7 1/3] USB: Also check for ->match
2020-08-18 9:00 ` [PATCH v7 1/3] USB: Also check for ->match Greg Kroah-Hartman
@ 2020-08-18 9:42 ` Bastien Nocera
2020-08-18 9:51 ` Greg Kroah-Hartman
0 siblings, 1 reply; 6+ messages in thread
From: Bastien Nocera @ 2020-08-18 9:42 UTC (permalink / raw)
To: Greg Kroah-Hartman; +Cc: linux-usb, Alan Stern
On Tue, 2020-08-18 at 11:00 +0200, Greg Kroah-Hartman wrote:
> On Tue, Aug 04, 2020 at 01:38:32PM +0200, Bastien Nocera wrote:
> > We only ever used the ID table matching before, but we should
> > probably
> > also support an open-coded match function.
> >
> > Fixes: 88b7381a939de ("USB: Select better matching USB drivers when
> > available")
> > Signed-off-by: Bastien Nocera <hadess@hadess.net>
> > Acked-by: Alan Stern <stern@rowland.harvard.edu>
>
> The subject line does not make sense, what is "also"? Who is doing
> this?
>
> Coming back to this after a week I have no idea what is going on, so
> that's a sign that it needs to be reworded :(
It's actually been 2 weeks. Were there any other changes you wanted
made in this patchset, or is that going to be it?
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v7 1/3] USB: Also check for ->match
2020-08-18 9:42 ` Bastien Nocera
@ 2020-08-18 9:51 ` Greg Kroah-Hartman
0 siblings, 0 replies; 6+ messages in thread
From: Greg Kroah-Hartman @ 2020-08-18 9:51 UTC (permalink / raw)
To: Bastien Nocera; +Cc: linux-usb, Alan Stern
On Tue, Aug 18, 2020 at 11:42:23AM +0200, Bastien Nocera wrote:
> On Tue, 2020-08-18 at 11:00 +0200, Greg Kroah-Hartman wrote:
> > On Tue, Aug 04, 2020 at 01:38:32PM +0200, Bastien Nocera wrote:
> > > We only ever used the ID table matching before, but we should
> > > probably
> > > also support an open-coded match function.
> > >
> > > Fixes: 88b7381a939de ("USB: Select better matching USB drivers when
> > > available")
> > > Signed-off-by: Bastien Nocera <hadess@hadess.net>
> > > Acked-by: Alan Stern <stern@rowland.harvard.edu>
> >
> > The subject line does not make sense, what is "also"? Who is doing
> > this?
> >
> > Coming back to this after a week I have no idea what is going on, so
> > that's a sign that it needs to be reworded :(
>
> It's actually been 2 weeks. Were there any other changes you wanted
> made in this patchset, or is that going to be it?
I think that's it.
^ permalink raw reply [flat|nested] 6+ messages in thread