bb8822cbbc
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>
59 lines
1.6 KiB
C
59 lines
1.6 KiB
C
// 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 */
|