Hi Dan,
>Hello Pawel Laszczak,
>
>The patch 7733f6c32e36: "usb: cdns3: Add Cadence USB3 DRD Driver"
>from Aug 26, 2019, leads to the following static checker warning:
>
> drivers/usb/cdns3/ep0.c:335 cdns3_ep0_feature_handle_device()
> error: scheduling with locks held: 'spin_lock:lock'
>
>drivers/usb/cdns3/ep0.c
> 309
> 310 priv_dev->u2_allowed = !!set;
> 311 break;
> 312 case USB_DEVICE_LTM_ENABLE:
> 313 ret = -EINVAL;
> 314 break;
> 315 case USB_DEVICE_TEST_MODE:
> 316 if (state != USB_STATE_CONFIGURED || speed > USB_SPEED_HIGH)
> 317 return -EINVAL;
> 318
> 319 tmode = le16_to_cpu(ctrl->wIndex);
> 320
> 321 if (!set || (tmode & 0xff) != 0)
> 322 return -EINVAL;
> 323
> 324 switch (tmode >> 8) {
> 325 case TEST_J:
> 326 case TEST_K:
> 327 case TEST_SE0_NAK:
> 328 case TEST_PACKET:
> 329 cdns3_ep0_complete_setup(priv_dev, 0, 1);
> 330 /**
> 331 * Little delay to give the controller some time
> 332 * for sending status stage.
> 333 * This time should be less then 3ms.
> 334 */
> 335 usleep_range(1000, 2000);
> ^^^^^^^^^^^^^^^^^^^^^^^^
>This is called with locks held and IRQs disabled in
>cdns3_device_thread_irq_handler(). The call tree is:
>
>cdns3_device_thread_irq_handler()
> cdns3_check_ep0_interrupt_proceed()
> cdns3_ep0_setup_phase()
> cdns3_ep0_standard_request()
> cdns3_req_ep0_handle_feature()
> cdns3_ep0_feature_handle_device()
>
>You would need to have certain debug config options enabled to see the
>might_sleep() warnings and probably USB_DEVICE_TEST_MODE isn't used
>very often.
It's very rarely used options. This part is required only during USB Certification process to pass
some tests. After completion the device under test can be even rebooted.
I think that It should be replaced by udelay/mdelay function. I understand that the problem occurred
because we can't use sleep functions when lock is held, or interrupt are disabled.
I will post the fix patch ASAP.
Thank you for letting me know.
>
> 336 cdns3_set_register_bit(&priv_dev->regs->usb_cmd,
> 337 USB_CMD_STMODE |
> 338 USB_STS_TMODE_SEL(tmode - 1));
> 339 break;
> 340 default:
> 341 ret = -EINVAL;
> 342 }
> 343 break;
> 344 default:
> 345 ret = -EINVAL;
> 346 }
>
>regards,
>dan carpenter
Regards,
Pawell
