sample USB Driver / Probe not getting called
Hi All,
Is there any way to call a sample USB driver whenever a USB device is attached to the system irrespective of the class and type of the device?
To do this, LDD3, chap 13 mention that for USB device table, we only need to add the driver_info entry as 42.
However if I do this, my probe is never getting called.
Now, I give the vendor and product id of this Mouse to the device_id table and load my driver again. Still the probe is not getting called.
Is it that USB core is getting the proper driver for this mouse before my driver entry in the list?
Am I missing something?
Regards,
Abhijit Pawar
Quoted 9 lines · Abhijit Pawar
Hi All,
Is there any way to call a sample USB driver whenever a USB device is attached to the system irrespective of the class and type of the device?To do this, LDD3, chap 13 mention that for USB device table, we only need to add the
driver_infoentry as 42.However if I do this, my probe is never getting called.
Quoted 8 lines
Now, I give the vendor and product id of this Mouse to the
device_idtable and load my driver again. Still the probe is not getting called.Is it that USB core is getting the proper driver for this mouse before my driver entry in the list?
Am I missing something?
probe function will get called only if no other driver is attached to the device. Make sure the device does not have any other driver. Please refer line 290 and 291.
drivers/base/dd.c:
270 static int __driver_attach(struct device *dev, void *data) 271 {
272 struct device_driver *drv = data;
273
274 /*
275 * Lock device and try to bind to it. We drop the error 276 * here and always return 0, because we need to keep trying 277 * to bind to devices and some drivers will return an error 278 * simply if it didn't support the device. 279 * 280 * driver_probe_device() will spit a warning if there 281 * is an error. 282 */
283
284 if (!driver_match_device(drv, dev))
285 return 0;
286
287 if (dev->parent) /* Needed for USB */
288 device_lock(dev->parent);
289 device_lock(dev);
290 if (!dev->driver)
291 driver_probe_device(drv, dev);
Quoted 36 lines · selvamuthukumar v
Quoted 9 lines · Abhijit Pawar
Hi All,
Is there any way to call a sample USB driver whenever a USB device is attached to the system irrespective of the class and type of the device?To do this, LDD3, chap 13 mention that for USB device table, we only need to add the
driver_infoentry as 42.However if I do this, my probe is never getting called.
Quoted 8 lines
Now, I give the vendor and product id of this Mouse to the
device_idtable and load my driver again. Still the probe is not getting called.Is it that USB core is getting the proper driver for this mouse before my driver entry in the list?
Am I missing something?
probe function will get called only if no other driver is attached to the device. Make sure the device does not have any other driver. Please refer line 290 and 291.
drivers/base/dd.c:
270 static int__driver_attach(struct device *dev, void *data)271 {
272 structdevice_driver*drv = data;
273
274 /*275 * Lock device and try to bind to it. We drop the error 276 * here and always return 0, because we need to keep trying 277 * to bind to devices and some drivers will return an error 278 * simply if it didn't support the device. 279 * 280 * driver_probe_device() will spit a warning if there 281 * is an error. 282 */
Quoted 9 lines
283
284 if (!driver_match_device(drv, dev))
285 return 0;
286
287 if (dev->parent) /* Needed for USB */
288device_lock(dev->parent);
289device_lock(dev);
290 if (!dev->driver)
291driver_probe_device(drv, dev);
Thanks for reference to this function. It seems that there isnt any way to override the already attached driver to the device.
Is there any?
Regards,
Abhijit Pawar
Quoted 28 lines · Abhijit Pawar
Quoted 25 lines · selvamuthukumar v
Quoted 10 lines · On Mon, Oct 17, 2011 at 3:05 PM, Abhijit Pawar<[email protected]> ?wrote:
Hi All,
Is there any way to call a sample USB driver whenever a USB device is attached to the system irrespective of the class and type of the device?To do this, LDD3, chap 13 mention that for USB device table, we only need to add the
driver_infoentry as 42.However if I do this, my probe is never getting called.
Quoted 8 lines
Now, I give the vendor and product id of this Mouse to the
device_idtable and load my driver again. Still the probe is not getting called.Is it that USB core is getting the proper driver for this mouse before my driver entry in the list?
Am I missing something?
probe function will get called only if no other driver is attached to the device. Make sure the device does not have any other driver. Please refer line 290 and 291.
Quoted 7 lines
Quoted 2 lines
290 ? ? ? ? if (!dev->driver)
291 ? ? ? ? ? ? ? ?driver_probe_device(drv, dev);Thanks for reference to this function. It seems that there isnt any way to override the already attached driver to the device.
Is there any?
If already bounded driver is compiled as module you can rmmod. But overriding option is not given may be because, the current loaded driver may be doing an important operation, interrupting it may leave the device in undefined state.