From: Christopher Freeman <cfreeman@nvidia.com>
To: <ldewangan@nvidia.com>, <swarren@nvidia.com>,
<vinod.koul@intel.com>, <dan.j.williams@intel.com>
Cc: <dmaengine@vger.kernel.org>, <linux-tegra@vger.kernel.org>,
<linux-kernel@vger.kernel.org>,
Christopher Freeman <cfreeman@nvidia.com>
Subject: [PATCH v1 3/3] dma: tegra: avoid int overflow for transferred count
Date: Tue, 6 May 2014 14:22:23 -0700 [thread overview]
Message-ID: <1399411343-12222-4-git-send-email-cfreeman@nvidia.com> (raw)
In-Reply-To: <1399411343-12222-1-git-send-email-cfreeman@nvidia.com>
bytes_transferred will overflow during long audio playbacks. Since
the driver only ever consults this value modulo bytes_requested, store the
value modulo bytes_requested.
Signed-off-by: Christopher Freeman <cfreeman@nvidia.com>
---
drivers/dma/tegra20-apb-dma.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c
index 094e97d..e1b80a4 100644
--- a/drivers/dma/tegra20-apb-dma.c
+++ b/drivers/dma/tegra20-apb-dma.c
@@ -583,7 +583,9 @@ static void handle_once_dma_done(struct tegra_dma_channel *tdc,
tdc->busy = false;
sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
dma_desc = sgreq->dma_desc;
- dma_desc->bytes_transferred += sgreq->req_len;
+ dma_desc->bytes_transferred = (dma_desc->bytes_transferred +
+ sgreq->req_len) %
+ dma_desc->bytes_requested;
list_del(&sgreq->node);
if (sgreq->last_sg) {
@@ -613,7 +615,9 @@ static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
dma_desc = sgreq->dma_desc;
- dma_desc->bytes_transferred += sgreq->req_len;
+ dma_desc->bytes_transferred = (dma_desc->bytes_transferred +
+ sgreq->req_len) %
+ dma_desc->bytes_requested;
/* Callback need to be call */
if (!dma_desc->cb_count)
@@ -762,8 +766,10 @@ static void tegra_dma_terminate_all(struct dma_chan *dc)
if (!list_empty(&tdc->pending_sg_req) && was_busy) {
sgreq = list_first_entry(&tdc->pending_sg_req,
typeof(*sgreq), node);
- sgreq->dma_desc->bytes_transferred +=
- get_current_xferred_count(tdc, sgreq, wcount);
+ sgreq->dma_desc->bytes_transferred =
+ (sgreq->dma_desc->bytes_transferred +
+ get_current_xferred_count(tdc, sgreq, wcount)) %
+ sgreq->dma_desc->bytes_requested;
}
tegra_dma_resume(tdc);
@@ -838,8 +844,7 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) {
if (dma_desc->txd.cookie == cookie) {
residual = dma_desc->bytes_requested -
- (dma_desc->bytes_transferred %
- dma_desc->bytes_requested);
+ dma_desc->bytes_transferred;
dma_set_residue(txstate, residual);
ret = dma_desc->dma_status;
spin_unlock_irqrestore(&tdc->lock, flags);
@@ -859,8 +864,7 @@ static enum dma_status tegra_dma_tx_status(struct dma_chan *dc,
typeof(*first_entry), node);
residual = dma_desc->bytes_requested -
- (dma_desc->bytes_transferred %
- dma_desc->bytes_requested);
+ dma_desc->bytes_transferred;
/* hw byte count only applies to current transaction */
if (first_entry &&
--
1.7.9.5
next prev parent reply other threads:[~2014-05-06 21:22 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-06 21:22 [PATCH v1 0/3] Tegra DMA residue improvements Christopher Freeman
2014-05-06 21:22 ` [PATCH v1 1/3] dma: tegra: finer granularity residual for tx_status Christopher Freeman
2014-05-07 16:37 ` Stephen Warren
2014-05-07 22:37 ` Christopher Freeman
2014-05-12 17:27 ` Stephen Warren
2014-05-21 6:00 ` Vinod Koul
2014-05-06 21:22 ` [PATCH v1 2/3] dma: tegra: change interrupt-related log levels Christopher Freeman
2014-05-06 21:22 ` Christopher Freeman [this message]
2014-05-07 16:38 ` [PATCH v1 3/3] dma: tegra: avoid int overflow for transferred count Stephen Warren
2014-05-07 19:15 ` Lars-Peter Clausen
2014-05-07 22:50 ` Christopher Freeman
2014-05-07 6:38 ` [PATCH v1 0/3] Tegra DMA residue improvements Lars-Peter Clausen
2014-05-07 21:27 ` Christopher Freeman
2014-05-21 5:52 ` Vinod Koul
2014-05-21 6:58 ` Lars-Peter Clausen
2014-05-21 11:06 ` Vinod Koul
2014-05-21 16:21 ` Stephen Warren
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1399411343-12222-4-git-send-email-cfreeman@nvidia.com \
--to=cfreeman@nvidia.com \
--cc=dan.j.williams@intel.com \
--cc=dmaengine@vger.kernel.org \
--cc=ldewangan@nvidia.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tegra@vger.kernel.org \
--cc=swarren@nvidia.com \
--cc=vinod.koul@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox