From: Hsin-Yi Wang <hsinyi@chromium.org>
To: linux-arm-kernel@lists.infradead.org
Cc: Matthias Brugger <matthias.bgg@gmail.com>,
Wolfram Sang <wsa@the-dreams.de>, Jun Gao <jun.gao@mediatek.com>,
Hsin-Yi Wang <hsinyi@chromium.org>,
Ryder Lee <ryder.lee@mediatek.com>,
linux-i2c@vger.kernel.org, linux-mediatek@lists.infradead.org,
linux-kernel@vger.kernel.org
Subject: [PATCH] i2c: mediatek: modify threshold passed to i2c_get_dma_safe_msg_buf()
Date: Fri, 15 Feb 2019 17:02:02 +0800 [thread overview]
Message-ID: <20190215090202.157100-1-hsinyi@chromium.org> (raw)
i2c_get_dma_safe_msg_buf() allocates space based on msg->len. If threshold is
0 and msg->len is also 0, function makes zero-length allocation, which returns
a special ZERO_SIZE_PTR instead of a NULL pointer, and this will cause later
code to fail. Modify the threshold to > 0 so the function returns NULL pointer.
Fixes: fc66b39fe36a ("i2c: mediatek: Use DMA safe buffers for i2c transactions")
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
---
drivers/i2c/busses/i2c-mt65xx.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index a74ef76705e0..2bb4d20ead32 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -503,7 +503,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
writel(I2C_DMA_CON_RX, i2c->pdmabase + OFFSET_CON);
- dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 0);
+ dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
if (!dma_rd_buf)
return -ENOMEM;
@@ -526,7 +526,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
writel(I2C_DMA_CON_TX, i2c->pdmabase + OFFSET_CON);
- dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 0);
+ dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
if (!dma_wr_buf)
return -ENOMEM;
@@ -549,7 +549,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG);
writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_CON);
- dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 0);
+ dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
if (!dma_wr_buf)
return -ENOMEM;
@@ -561,7 +561,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
return -ENOMEM;
}
- dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 0);
+ dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 1);
if (!dma_rd_buf) {
dma_unmap_single(i2c->dev, wpaddr,
msgs->len, DMA_TO_DEVICE);
--
2.18.1
next reply other threads:[~2019-02-15 9:02 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-15 9:02 Hsin-Yi Wang [this message]
2019-02-15 9:09 ` [PATCH] i2c: mediatek: modify threshold passed to i2c_get_dma_safe_msg_buf() Wolfram Sang
2019-02-15 9:17 ` Hsin-Yi Wang
2019-02-15 9:25 ` Wolfram Sang
2019-02-15 16:36 ` Wolfram Sang
2019-02-22 6:04 ` Hsin-Yi Wang
2019-03-08 11:29 ` Wolfram Sang
2019-03-08 14:39 ` Hsin-Yi Wang
2019-03-08 14:52 ` Wolfram Sang
2019-03-08 16:22 ` Hsin-Yi Wang
2019-03-09 9:42 ` Wolfram Sang
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=20190215090202.157100-1-hsinyi@chromium.org \
--to=hsinyi@chromium.org \
--cc=jun.gao@mediatek.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=matthias.bgg@gmail.com \
--cc=ryder.lee@mediatek.com \
--cc=wsa@the-dreams.de \
/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;
as well as URLs for NNTP newsgroup(s).