This is a note to let you know that I've just added the patch titled
i2c: mediatek: move dma reset before i2c reset
to the 5.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
i2c-mediatek-move-dma-reset-before-i2c-reset.patch
and it can be found in the queue-5.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7f3c26999d98e00f80c0c7af2c277976dcbdf622
Author: Qii Wang <qii.wang@xxxxxxxxxxxx>
Date: Fri Oct 30 19:58:01 2020 +0800
i2c: mediatek: move dma reset before i2c reset
[ Upstream commit aafced673c06b7c77040c1df42e2e965be5d0376 ]
The i2c driver default do dma reset after i2c reset, but sometimes
i2c reset will trigger dma tx2rx, then apdma write data to dram
which has been i2c_put_dma_safe_msg_buf(kfree). Move dma reset
before i2c reset in mtk_i2c_init_hw to fix it.
Signed-off-by: Qii Wang <qii.wang@xxxxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 0cbdfbe605b55..33de99b7bc20c 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -475,6 +475,10 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c)
{
u16 control_reg;
+ writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST);
+ udelay(50);
+ writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
+
mtk_i2c_writew(i2c, I2C_SOFT_RST, OFFSET_SOFTRESET);
/* Set ioconfig */
@@ -529,10 +533,6 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c)
mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL);
mtk_i2c_writew(i2c, I2C_DELAY_LEN, OFFSET_DELAY_LEN);
-
- writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST);
- udelay(50);
- writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
}
static const struct i2c_spec_values *mtk_i2c_get_spec(unsigned int speed)
