1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * i2c-stm32.h 4 * 5 * Copyright (C) M'boumba Cedric Madianga 2017 6 * Copyright (C) STMicroelectronics 2017 7 * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> 8 * 9 */ 10 11 #ifndef _I2C_STM32_H 12 #define _I2C_STM32_H 13 14 #include <linux/dma-direction.h> 15 #include <linux/dmaengine.h> 16 #include <linux/dma-mapping.h> 17 18 enum stm32_i2c_speed { 19 STM32_I2C_SPEED_STANDARD, /* 100 kHz */ 20 STM32_I2C_SPEED_FAST, /* 400 kHz */ 21 STM32_I2C_SPEED_FAST_PLUS, /* 1 MHz */ 22 STM32_I2C_SPEED_END, 23 }; 24 25 /** 26 * struct stm32_i2c_dma - DMA specific data 27 * @chan_tx: dma channel for TX transfer 28 * @chan_rx: dma channel for RX transfer 29 * @chan_using: dma channel used for the current transfer (TX or RX) 30 * @dma_buf: dma buffer 31 * @dma_len: dma buffer len 32 * @dma_transfer_dir: dma transfer direction indicator 33 * @dma_data_dir: dma transfer mode indicator 34 * @dma_complete: dma transfer completion 35 */ 36 struct stm32_i2c_dma { 37 struct dma_chan *chan_tx; 38 struct dma_chan *chan_rx; 39 struct dma_chan *chan_using; 40 dma_addr_t dma_buf; 41 unsigned int dma_len; 42 enum dma_transfer_direction dma_transfer_dir; 43 enum dma_data_direction dma_data_dir; 44 struct completion dma_complete; 45 }; 46 47 struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev, 48 dma_addr_t phy_addr, 49 u32 txdr_offset, u32 rxdr_offset); 50 51 void stm32_i2c_dma_free(struct stm32_i2c_dma *dma); 52 53 int stm32_i2c_prep_dma_xfer(struct device *dev, struct stm32_i2c_dma *dma, 54 bool rd_wr, u32 len, u8 *buf, 55 dma_async_tx_callback callback, 56 void *dma_async_param); 57 58 #endif /* _I2C_STM32_H */ 59