i2c-stm32.h
/* SPDX-License-Identifier: GPL-2.0 */
/*
* i2c-stm32.h
*
* Copyright (C) M'boumba Cedric Madianga 2017
* Copyright (C) STMicroelectronics 2017
* Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
*
*/
#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 */
STM32_I2C_SPEED_FAST_PLUS, /* 1 MHz */
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 */