diff options
| author | Eddie Huang <eddie.huang@mediatek.com> | 2015-08-06 15:22:10 +0800 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2015-08-11 16:53:11 +0200 |
| commit | ea89ef1f7bf7c71b4f533a6ffb3f6f124890b37b (patch) | |
| tree | 2ed339ad06320608a89ee8f2e58fa29b51d05fd9 /drivers/i2c | |
| parent | 66621f96c95175cc64d91dd213781bf65bbf8ec4 (diff) | |
| download | linux-rt-ea89ef1f7bf7c71b4f533a6ffb3f6f124890b37b.tar.gz | |
i2c: mediatek: Reset DMA engine in hardware init function
Reset DMA in hardware init function to avoid unknown hardware state
before do any I2C operation.
Signed-off-by: Liguo Zhang <liguo.zhang@mediatek.com>
Signed-off-by: Eddie Huang <eddie.huang@mediatek.com>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-mt65xx.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index 9920eef74672..e28ad4c17d3d 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -59,6 +59,7 @@ #define I2C_DMA_START_EN 0x0001 #define I2C_DMA_INT_FLAG_NONE 0x0000 #define I2C_DMA_CLR_FLAG 0x0000 +#define I2C_DMA_HARD_RST 0x0002 #define I2C_DEFAULT_SPEED 100000 /* hz */ #define MAX_FS_MODE_SPEED 400000 @@ -81,6 +82,7 @@ enum DMA_REGS_OFFSET { OFFSET_INT_FLAG = 0x0, OFFSET_INT_EN = 0x04, OFFSET_EN = 0x08, + OFFSET_RST = 0x0c, OFFSET_CON = 0x18, OFFSET_TX_MEM_ADDR = 0x1c, OFFSET_RX_MEM_ADDR = 0x20, @@ -262,6 +264,10 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c) I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN; writew(control_reg, i2c->base + OFFSET_CONTROL); writew(I2C_DELAY_LEN, i2c->base + OFFSET_DELAY_LEN); + + writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST); + udelay(50); + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); } /* |