lkml.org 
[lkml]   [2018]   [May]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH v2 1/2] usb: dwc3: gadget: Correct handling of scattergather lists
Date
Hi All,

Please let me know if the changes in this patch are okay . If the changes looks fine , can we proceed with this patch.

Thanks,
Anurag Kumar Vulisha

>-----Original Message-----
>From: v.anuragkumar@gmail.com [mailto:v.anuragkumar@gmail.com]
>Sent: Tuesday, March 27, 2018 4:35 PM
>To: Felipe Balbi <balbi@kernel.org>; Greg Kroah-Hartman
><gregkh@linuxfoundation.org>
>Cc: linux-usb@vger.kernel.org; linux-kernel@vger.kernel.org; Ajay Yugalkishore
>Pandey <APANDEY@xilinx.com>; v.anuragkumar@gmail.com; Anurag Kumar Vulisha
><anuragku@xilinx.com>
>Subject: [PATCH v2 1/2] usb: dwc3: gadget: Correct handling of scattergather lists
>
>From: Anurag Kumar Vulisha <anuragku@xilinx.com>
>
>The code logic in dwc3_prepare_one_trb() incorrectly uses the address and length
>fields present in req packet for mapping TRB's instead of using the address and length
>fields of scattergather lists. This patch correct's the code to use sg->address and sg-
>>length when scattergather lists are present.
>
>Signed-off-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
>---
> Changes in v2:
> 1. Split the single patch into 2 patches as suggested by Felipe Balbi
> 2. Renamed sg_to_start variable to start_sg
>---
> drivers/usb/dwc3/core.h | 2 ++
> drivers/usb/dwc3/gadget.c | 25 ++++++++++++++++++++++---
> 2 files changed, 24 insertions(+), 3 deletions(-)
>
>diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index
>860d2bc..1406c4f 100644
>--- a/drivers/usb/dwc3/core.h
>+++ b/drivers/usb/dwc3/core.h
>@@ -718,6 +718,7 @@ struct dwc3_hwparams {
> * @list: a list_head used for request queueing
> * @dep: struct dwc3_ep owning this request
> * @sg: pointer to first incomplete sg
>+ * @start_sg: pointer to the sg which should be queued next
> * @num_pending_sgs: counter to pending sgs
> * @remaining: amount of data remaining
> * @epnum: endpoint number to which this request refers @@ -734,6 +735,7 @@
>struct dwc3_request {
> struct list_head list;
> struct dwc3_ep *dep;
> struct scatterlist *sg;
>+ struct scatterlist *start_sg;
>
> unsigned num_pending_sgs;
> unsigned remaining;
>diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index
>2bda4eb..330a4de 100644
>--- a/drivers/usb/dwc3/gadget.c
>+++ b/drivers/usb/dwc3/gadget.c
>@@ -978,11 +978,19 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
> struct dwc3_request *req, unsigned chain, unsigned node) {
> struct dwc3_trb *trb;
>- unsigned length = req->request.length;
>+ unsigned int length;
>+ dma_addr_t dma;
> unsigned stream_id = req->request.stream_id;
> unsigned short_not_ok = req->request.short_not_ok;
> unsigned no_interrupt = req->request.no_interrupt;
>- dma_addr_t dma = req->request.dma;
>+
>+ if (req->request.num_sgs > 0) {
>+ length = sg_dma_len(req->start_sg);
>+ dma = sg_dma_address(req->start_sg);
>+ } else {
>+ length = req->request.length;
>+ dma = req->request.dma;
>+ }
>
> trb = &dep->trb_pool[dep->trb_enqueue];
>
>@@ -1048,7 +1056,7 @@ static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
>static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
> struct dwc3_request *req)
> {
>- struct scatterlist *sg = req->sg;
>+ struct scatterlist *sg = req->start_sg;
> struct scatterlist *s;
> int i;
>
>@@ -1081,6 +1089,16 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep
>*dep,
> dwc3_prepare_one_trb(dep, req, chain, i);
> }
>
>+ /*
>+ * There can be a situation where all sgs in sglist are not
>+ * queued because of insufficient trb number. To handle this
>+ * case, update start_sg to next sg to be queued, so that
>+ * we have free trbs we can continue queuing from where we
>+ * previously stopped
>+ */
>+ if (chain)
>+ req->start_sg = sg_next(s);
>+
> if (!dwc3_calc_trbs_left(dep))
> break;
> }
>@@ -1171,6 +1189,7 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep)
> return;
>
> req->sg = req->request.sg;
>+ req->start_sg = req->sg;
> req->num_pending_sgs = req->request.num_mapped_sgs;
>
> if (req->num_pending_sgs > 0)
>--
>2.1.1

\
 
 \ /
  Last update: 2018-05-02 16:42    [W:0.069 / U:6.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site