Hi Tejas,
On Tuesday, January 07, 2020 18:16, Tejas Joglekar wrote:
Hi, On 1/7/2020 12:44 PM, Ran Wang wrote:
According to original commit c96e6725db9d6a ("usb: dwc3: gadget: Correct the logic for queuing sgs"), we would only kick off another transfer in case of req->num_pending_sgs > 0.
The commit 8c7d4b7b3d43 ("usb: dwc3: gadget: Fix logical condition") fixes the commit f38e35dd84e2 (usb: dwc3: gadget: split dwc3_gadget_ep_cleanup_completed_requests()).
Yes, actually I have tried to dig the history of this implementation as much as I can. and the commit I mentioned looks like the first one to add this function.
However, current logic will do this as long as req->remaining > 0, this will include the case of non-sgs (both dwc3_gadget_ep_request_completed(req) and req->num_pending_sgs are 0) that we did not want to.
Without this fix, we observed dwc3 got stuck on Layerscape plaftorms (such as LS1088ARDB) when enabling gadget (mass storage function) as below:
Similar issue was reported by Thinh after my fix, and he has submitted a patch for the same. You can refer the discussion https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatch work.kernel.org%2Fpatch%2F11292087%2F&data=02%7C01%7Cran.wan g_1%40nxp.com%7C97345f38c19849e5a82608d7935a8d31%7C686ea1d3bc2b 4c6fa92cd99c5c301635%7C0%7C0%7C637139889495749889&sdata=tcV6 FWjqvYYO7BCByACqAg%2FB%2B%2Fz3NC%2B20%2BIEVuyfJc4%3D&reser ved=0.
Thanks for this information. I will follow that thread.
Regards, Ran
[ 27.923959] Mass Storage Function, version: 2009/09/11 [ 27.929115] LUN: removable file: (no medium) [ 27.933432] LUN: file: /run/media/sda1/419/test [ 27.937963] Number of LUNs=1 [ 27.941042] g_mass_storage gadget: Mass Storage Gadget, version:
2009/09/11
[ 27.948019] g_mass_storage gadget: userspace failed to provide
iSerialNumber
[ 27.955069] g_mass_storage gadget: g_mass_storage ready [ 28.411188] g_mass_storage gadget: super-speed config #1: Linux File-
Backed Storage
[ 48.319766] g_mass_storage gadget: super-speed config #1: Linux File-
Backed Storage
[ 68.320794] g_mass_storage gadget: super-speed config #1: Linux File-
Backed Storage
[ 88.319898] g_mass_storage gadget: super-speed config #1: Linux File-
Backed Storage
[ 108.320808] g_mass_storage gadget: super-speed config #1: Linux File-Backed Storage [ 128.323419] g_mass_storage gadget: super-speed config #1: Linux File-Backed Storage [ 148.320857] g_mass_storage gadget: super-speed config #1: Linux File-Backed Storage [ 148.362023] g_mass_storage gadget: super-speed config #0: unconfigured
Fixes: 8c7d4b7b3d43 ("usb: dwc3: gadget: Fix logical condition")
Cc: stable@vger.kernel.org Signed-off-by: Ran Wang ran.wang_1@nxp.com
drivers/usb/dwc3/gadget.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 0c960a9..5b0f02f 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2491,7 +2491,7 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
req->request.actual = req->request.length - req->remaining;
- if (!dwc3_gadget_ep_request_completed(req) ||
- if (!dwc3_gadget_ep_request_completed(req) && req->num_pending_sgs) { __dwc3_gadget_kick_transfer(dep); goto out;
Thanks & Regards, Tejas Joglekar