i2c/busses/i2c-stm32.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * i2c-stm32.h
0004  *
0005  * Copyright (C) M'boumba Cedric Madianga 2017
0006  * Copyright (C) STMicroelectronics 2017
0007  * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com>
0008  *
0009  */
0010
0011 #ifndef _I2C_STM32_H
0012 #define _I2C_STM32_H
0013
0014 #include <linux/dma-direction.h>
0015 #include <linux/dmaengine.h>
0016 #include <linux/dma-mapping.h>
0017
0018 enum stm32_i2c_speed {
0019     STM32_I2C_SPEED_STANDARD, /* 100 kHz */
0020     STM32_I2C_SPEED_FAST, /* 400 kHz */
0021     STM32_I2C_SPEED_FAST_PLUS, /* 1 MHz */
0022     STM32_I2C_SPEED_END,
0023 };
0024
0025 /**
0026  * struct stm32_i2c_dma - DMA specific data
0027  * @chan_tx: dma channel for TX transfer
0028  * @chan_rx: dma channel for RX transfer
0029  * @chan_using: dma channel used for the current transfer (TX or RX)
0030  * @dma_buf: dma buffer
0031  * @dma_len: dma buffer len
0032  * @dma_transfer_dir: dma transfer direction indicator
0033  * @dma_data_dir: dma transfer mode indicator
0034  * @dma_complete: dma transfer completion
0035  */
0036 struct stm32_i2c_dma {
0037     struct dma_chan *chan_tx;
0038     struct dma_chan *chan_rx;
0039     struct dma_chan *chan_using;
0040     dma_addr_t dma_buf;
0041     unsigned int dma_len;
0042     enum dma_transfer_direction dma_transfer_dir;
0043     enum dma_data_direction dma_data_dir;
0044     struct completion dma_complete;
0045 };
0046
0047 struct stm32_i2c_dma *stm32_i2c_dma_request(struct device *dev,
0048                         dma_addr_t phy_addr,
0049                         u32 txdr_offset, u32 rxdr_offset);
0050
0051 void stm32_i2c_dma_free(struct stm32_i2c_dma *dma);
0052
0053 int stm32_i2c_prep_dma_xfer(struct device *dev, struct stm32_i2c_dma *dma,
0054                 bool rd_wr, u32 len, u8 *buf,
0055                 dma_async_tx_callback callback,
0056                 void *dma_async_param);
0057
0058 #endif /* _I2C_STM32_H */