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 */