diff options
| author | Jun Gao <jun.gao@mediatek.com> | 2018-09-06 21:15:29 +0800 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2018-09-06 20:33:15 +0200 |
| commit | fc66b39fe36acfd06f716e338de7cd8f9550fad2 (patch) | |
| tree | b3d80ba277025afffd1bfb253dcc12965f0797d1 /drivers/i2c/busses | |
| parent | 9cbeeca05049b1109e7e445369898b8a88d5ea7b (diff) | |
| download | linux-fc66b39fe36acfd06f716e338de7cd8f9550fad2.tar.bz2 | |
i2c: mediatek: Use DMA safe buffers for i2c transactions
DMA mode will always be used in i2c transactions, try to allocate
a DMA safe buffer if the buf of struct i2c_msg used is not DMA safe.
Signed-off-by: Jun Gao <jun.gao@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/busses')
| -rw-r--r-- | drivers/i2c/busses/i2c-mt65xx.c | 62 |
1 files changed, 55 insertions, 7 deletions
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index 1e57f58fcb00..a74ef76705e0 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -441,6 +441,8 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, u16 control_reg; u16 restart_flag = 0; u32 reg_4g_mode; + u8 *dma_rd_buf = NULL; + u8 *dma_wr_buf = NULL; dma_addr_t rpaddr = 0; dma_addr_t wpaddr = 0; int ret; @@ -500,10 +502,18 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, if (i2c->op == I2C_MASTER_RD) { writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); writel(I2C_DMA_CON_RX, i2c->pdmabase + OFFSET_CON); - rpaddr = dma_map_single(i2c->dev, msgs->buf, + + dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 0); + if (!dma_rd_buf) + return -ENOMEM; + + rpaddr = dma_map_single(i2c->dev, dma_rd_buf, msgs->len, DMA_FROM_DEVICE); - if (dma_mapping_error(i2c->dev, rpaddr)) + if (dma_mapping_error(i2c->dev, rpaddr)) { + i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, false); + return -ENOMEM; + } if (i2c->dev_comp->support_33bits) { reg_4g_mode = mtk_i2c_set_4g_mode(rpaddr); @@ -515,10 +525,18 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, } else if (i2c->op == I2C_MASTER_WR) { writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); writel(I2C_DMA_CON_TX, i2c->pdmabase + OFFSET_CON); - wpaddr = dma_map_single(i2c->dev, msgs->buf, + + dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 0); + if (!dma_wr_buf) + return -ENOMEM; + + wpaddr = dma_map_single(i2c->dev, dma_wr_buf, msgs->len, DMA_TO_DEVICE); - if (dma_mapping_error(i2c->dev, wpaddr)) + if (dma_mapping_error(i2c->dev, wpaddr)) { + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + return -ENOMEM; + } if (i2c->dev_comp->support_33bits) { reg_4g_mode = mtk_i2c_set_4g_mode(wpaddr); @@ -530,16 +548,39 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, } else { writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG); writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_CON); - wpaddr = dma_map_single(i2c->dev, msgs->buf, + + dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 0); + if (!dma_wr_buf) + return -ENOMEM; + + wpaddr = dma_map_single(i2c->dev, dma_wr_buf, msgs->len, DMA_TO_DEVICE); - if (dma_mapping_error(i2c->dev, wpaddr)) + if (dma_mapping_error(i2c->dev, wpaddr)) { + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + return -ENOMEM; - rpaddr = dma_map_single(i2c->dev, (msgs + 1)->buf, + } + + dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 0); + if (!dma_rd_buf) { + dma_unmap_single(i2c->dev, wpaddr, + msgs->len, DMA_TO_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + + return -ENOMEM; + } + + rpaddr = dma_map_single(i2c->dev, dma_rd_buf, (msgs + 1)->len, DMA_FROM_DEVICE); if (dma_mapping_error(i2c->dev, rpaddr)) { dma_unmap_single(i2c->dev, wpaddr, msgs->len, DMA_TO_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); + i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), false); + return -ENOMEM; } @@ -578,14 +619,21 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, if (i2c->op == I2C_MASTER_WR) { dma_unmap_single(i2c->dev, wpaddr, msgs->len, DMA_TO_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true); } else if (i2c->op == I2C_MASTER_RD) { dma_unmap_single(i2c->dev, rpaddr, msgs->len, DMA_FROM_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, true); } else { dma_unmap_single(i2c->dev, wpaddr, msgs->len, DMA_TO_DEVICE); dma_unmap_single(i2c->dev, rpaddr, (msgs + 1)->len, DMA_FROM_DEVICE); + + i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true); + i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), true); } if (ret == 0) { |