4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 88b1bb1f3b88e0bf20b05d543a53a5b99bd7ceb6 ]
Currently the link_state is uninitialized and the default value is 0(U0) before the first time we start the udc, and after we start the udc then stop the udc, the link_state will be undefined. We may have the following warnings if we start the udc again with an undefined link_state:
WARNING: CPU: 0 PID: 327 at drivers/usb/dwc3/gadget.c:294 dwc3_send_gadget_ep_cmd+0x304/0x308 dwc3 100e0000.hidwc3_0: wakeup failed --> -22 [...] Call Trace: [<c010f270>] (unwind_backtrace) from [<c010b3d8>] (show_stack+0x10/0x14) [<c010b3d8>] (show_stack) from [<c034a4dc>] (dump_stack+0x84/0x98) [<c034a4dc>] (dump_stack) from [<c0118000>] (__warn+0xe8/0x100) [<c0118000>] (__warn) from [<c0118050>](warn_slowpath_fmt+0x38/0x48) [<c0118050>] (warn_slowpath_fmt) from [<c0442ec0>](dwc3_send_gadget_ep_cmd+0x304/0x308) [<c0442ec0>] (dwc3_send_gadget_ep_cmd) from [<c0445e68>](dwc3_ep0_start_trans+0x48/0xf4) [<c0445e68>] (dwc3_ep0_start_trans) from [<c0446750>](dwc3_ep0_out_start+0x64/0x80) [<c0446750>] (dwc3_ep0_out_start) from [<c04451c0>](__dwc3_gadget_start+0x1e0/0x278) [<c04451c0>] (__dwc3_gadget_start) from [<c04452e0>](dwc3_gadget_start+0x88/0x10c) [<c04452e0>] (dwc3_gadget_start) from [<c045ee54>](udc_bind_to_driver+0x88/0xbc) [<c045ee54>] (udc_bind_to_driver) from [<c045f29c>](usb_gadget_probe_driver+0xf8/0x140) [<c045f29c>] (usb_gadget_probe_driver) from [<bf005424>](gadget_dev_desc_UDC_store+0xac/0xc4 [libcomposite]) [<bf005424>] (gadget_dev_desc_UDC_store [libcomposite]) from[<c023d8e0>] (configfs_write_file+0xd4/0x160) [<c023d8e0>] (configfs_write_file) from [<c01d51e8>] (__vfs_write+0x1c/0x114) [<c01d51e8>] (__vfs_write) from [<c01d5ff4>] (vfs_write+0xa4/0x168) [<c01d5ff4>] (vfs_write) from [<c01d6d40>] (SyS_write+0x3c/0x90) [<c01d6d40>] (SyS_write) from [<c0107400>] (ret_fast_syscall+0x0/0x3c)
Signed-off-by: Zeng Tao prime.zeng@hisilicon.com Signed-off-by: Felipe Balbi felipe.balbi@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/dwc3/gadget.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index a7f6255606443..bf1cb91ef494d 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1873,6 +1873,7 @@ static int __dwc3_gadget_start(struct dwc3 *dwc)
/* begin to receive SETUP packets */ dwc->ep0state = EP0_SETUP_PHASE; + dwc->link_state = DWC3_LINK_STATE_SS_DIS; dwc3_ep0_out_start(dwc);
dwc3_gadget_enable_irq(dwc);