From: Qii Wang qii.wang@mediatek.com
commit 05f6f7271a38c482c5021967433f7b698e102c45 upstream.
With the apdma remove hand-shake signal, it requirs special operation timing to reset i2c manually, otherwise the interrupt will not be triggered, i2c transmission will be timeout.
Fixes: 8426fe70cfa4("i2c: mediatek: Add apdma sync in i2c driver") Signed-off-by: Qii Wang qii.wang@mediatek.com Signed-off-by: Wolfram Sang wsa@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/i2c/busses/i2c-mt65xx.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-)
--- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -38,6 +38,7 @@ #define I2C_IO_CONFIG_OPEN_DRAIN 0x0003 #define I2C_IO_CONFIG_PUSH_PULL 0x0000 #define I2C_SOFT_RST 0x0001 +#define I2C_HANDSHAKE_RST 0x0020 #define I2C_FIFO_ADDR_CLR 0x0001 #define I2C_DELAY_LEN 0x0002 #define I2C_TIME_CLR_VALUE 0x0000 @@ -45,6 +46,7 @@ #define I2C_WRRD_TRANAC_VALUE 0x0002 #define I2C_RD_TRANAC_VALUE 0x0001 #define I2C_SCL_MIS_COMP_VALUE 0x0000 +#define I2C_CHN_CLR_FLAG 0x0000
#define I2C_DMA_CON_TX 0x0000 #define I2C_DMA_CON_RX 0x0001 @@ -54,7 +56,9 @@ #define I2C_DMA_START_EN 0x0001 #define I2C_DMA_INT_FLAG_NONE 0x0000 #define I2C_DMA_CLR_FLAG 0x0000 +#define I2C_DMA_WARM_RST 0x0001 #define I2C_DMA_HARD_RST 0x0002 +#define I2C_DMA_HANDSHAKE_RST 0x0004
#define MAX_SAMPLE_CNT_DIV 8 #define MAX_STEP_CNT_DIV 64 @@ -475,11 +479,24 @@ static void mtk_i2c_init_hw(struct mtk_i { 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); + if (i2c->dev_comp->dma_sync) { + writel(I2C_DMA_WARM_RST, i2c->pdmabase + OFFSET_RST); + udelay(10); + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); + udelay(10); + writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_HARD_RST, + i2c->pdmabase + OFFSET_RST); + mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST | I2C_SOFT_RST, + OFFSET_SOFTRESET); + udelay(10); + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); + mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET); + } else { + 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 */ if (i2c->use_push_pull)