diff options
| author | Pierre-Yves MORDRET <pierre-yves.mordret@st.com> | 2018-04-11 15:24:56 +0200 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2018-04-30 10:39:27 +0200 |
| commit | bb8822cbbc5334dc89b7415dbdc6d51421e74773 (patch) | |
| tree | a138672e52193648d10c44ceaad2c57ce375320a /drivers/i2c/busses/i2c-stm32.h | |
| parent | 9e48155f6bfe3d3896c8596f56cc2f76d344db3a (diff) | |
| download | linux-bb8822cbbc5334dc89b7415dbdc6d51421e74773.tar.bz2 | |
i2c: i2c-stm32: Add generic DMA API
This patch adds a generic DMA API to implement DMA support for i2c-stm32fx
drivers
Signed-off-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/busses/i2c-stm32.h')
| -rw-r--r-- | drivers/i2c/busses/i2c-stm32.h | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-stm32.h b/drivers/i2c/busses/i2c-stm32.h index d4f9cef251ac..868755f82f88 100644 --- a/drivers/i2c/busses/i2c-stm32.h +++ b/drivers/i2c/busses/i2c-stm32.h @@ -11,6 +11,10 @@ #ifndef _I2C_STM32_H #define _I2C_STM32_H +#include <linux/dma-direction.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> + enum stm32_i2c_speed { STM32_I2C_SPEED_STANDARD, /* 100 kHz */ STM32_I2C_SPEED_FAST, /* 400 kHz */ @@ -18,4 +22,37 @@ enum stm32_i2c_speed { STM32_I2C_SPEED_END, }; +/** + * struct stm32_i2c_dma - DMA specific data + * @chan_tx: dma channel for TX transfer + * @chan_rx: dma channel for RX transfer + * @chan_using: dma channel used for the current transfer (TX or RX) + * @dma_buf: dma buffer + * @dma_len: dma buffer len + * @dma_transfer_dir: dma transfer direction indicator + * @dma_data_dir: dma transfer mode indicator + * @dma_complete: dma transfer completion + */ +struct stm32_i2c_dma { + struct dma_chan *chan_tx; + struct dma_chan *chan_rx; + struct dma_chan *chan_using; + dma_addr_t dma_buf; + unsigned int dma_len; + enum dma_transfer_direction dma_transfer_dir; + enum dma_data_direction dma_data_dir; + struct completion dma_complete; +}; + +struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev, + dma_addr_t phy_addr, + u32 txdr_offset, u32 rxdr_offset); + +void stm32_i2c_dma_free(struct stm32_i2c_dma *dma); + +int stm32_i2c_prep_dma_xfer(struct device *dev, struct stm32_i2c_dma *dma, + bool rd_wr, u32 len, u8 *buf, + dma_async_tx_callback callback, + void *dma_async_param); + #endif /* _I2C_STM32_H */ |