linux/drivers/iio/dac/ad5686.h
Stefan Popa 1dbae4c6cd iio:dac:ad5686: Add AD5681R/AD5682R/AD5683/AD5683R support
The AD5681R/AD5682R/AD5683/AD5683R are a family of one channel DACs with
12-bit, 14-bit and 16-bit precision respectively. The devices have either
no built-in reference, or built-in 2.5V reference.

These devices are similar to AD5691R/AD5692R/AD5693/AD5693R except
with a few notable differences:
 * they use the SPI interface instead of I2C
 * in the write control register, DB18 and DB17 are used for setting the
   power mode, while DB16 is the REF bit. This is why a new regmap type
   was defined and checked accordingly.
 * the shift register is 24 bits wide, the first four bits are the command
   bits followed by the data bits. As the data comprises of 20-bit, 18-bit
   or 16-bit input code, this means that 4 LSB bits are don't care. This is
   why the data needs to be shifted on the left with four bits. Therefore,
   AD5683_REGMAP is checked inside a switch case in the ad5686_spi_write()
   function. On the other hand, similar devices such as AD5693R family,
   have the 4 MSB command bits followed by 4 don't care bits.

Datasheet:
http://www.analog.com/media/en/technical-documentation/data-sheets/AD5683R_5682R_5681R_5683.pdf

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-05-20 11:45:45 +01:00

146 lines
3.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* This file is part of AD5686 DAC driver
*
* Copyright 2018 Analog Devices Inc.
*/
#ifndef __DRIVERS_IIO_DAC_AD5686_H__
#define __DRIVERS_IIO_DAC_AD5686_H__
#include <linux/types.h>
#include <linux/cache.h>
#include <linux/mutex.h>
#include <linux/kernel.h>
#define AD5683_DATA(x) ((x) << 4)
#define AD5686_ADDR(x) ((x) << 16)
#define AD5686_CMD(x) ((x) << 20)
#define AD5686_ADDR_DAC(chan) (0x1 << (chan))
#define AD5686_ADDR_ALL_DAC 0xF
#define AD5686_CMD_NOOP 0x0
#define AD5686_CMD_WRITE_INPUT_N 0x1
#define AD5686_CMD_UPDATE_DAC_N 0x2
#define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3
#define AD5686_CMD_POWERDOWN_DAC 0x4
#define AD5686_CMD_LDAC_MASK 0x5
#define AD5686_CMD_RESET 0x6
#define AD5686_CMD_INTERNAL_REFER_SETUP 0x7
#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8
#define AD5686_CMD_READBACK_ENABLE 0x9
#define AD5686_LDAC_PWRDN_NONE 0x0
#define AD5686_LDAC_PWRDN_1K 0x1
#define AD5686_LDAC_PWRDN_100K 0x2
#define AD5686_LDAC_PWRDN_3STATE 0x3
#define AD5686_CMD_CONTROL_REG 0x4
#define AD5686_CMD_READBACK_ENABLE_V2 0x5
#define AD5683_REF_BIT_MSK BIT(12)
#define AD5693_REF_BIT_MSK BIT(12)
/**
* ad5686_supported_device_ids:
*/
enum ad5686_supported_device_ids {
ID_AD5671R,
ID_AD5672R,
ID_AD5675R,
ID_AD5676,
ID_AD5676R,
ID_AD5681R,
ID_AD5682R,
ID_AD5683,
ID_AD5683R,
ID_AD5684,
ID_AD5684R,
ID_AD5685R,
ID_AD5686,
ID_AD5686R,
ID_AD5691R,
ID_AD5692R,
ID_AD5693,
ID_AD5693R,
ID_AD5694,
ID_AD5694R,
ID_AD5695R,
ID_AD5696,
ID_AD5696R,
};
enum ad5686_regmap_type {
AD5683_REGMAP,
AD5686_REGMAP,
AD5693_REGMAP
};
struct ad5686_state;
typedef int (*ad5686_write_func)(struct ad5686_state *st,
u8 cmd, u8 addr, u16 val);
typedef int (*ad5686_read_func)(struct ad5686_state *st, u8 addr);
/**
* struct ad5686_chip_info - chip specific information
* @int_vref_mv: AD5620/40/60: the internal reference voltage
* @num_channels: number of channels
* @channel: channel specification
* @regmap_type: register map layout variant
*/
struct ad5686_chip_info {
u16 int_vref_mv;
unsigned int num_channels;
struct iio_chan_spec *channels;
enum ad5686_regmap_type regmap_type;
};
/**
* struct ad5446_state - driver instance specific data
* @spi: spi_device
* @chip_info: chip model specific constants, available modes etc
* @reg: supply regulator
* @vref_mv: actual reference voltage used
* @pwr_down_mask: power down mask
* @pwr_down_mode: current power down mode
* @use_internal_vref: set to true if the internal reference voltage is used
* @data: spi transfer buffers
*/
struct ad5686_state {
struct device *dev;
const struct ad5686_chip_info *chip_info;
struct regulator *reg;
unsigned short vref_mv;
unsigned int pwr_down_mask;
unsigned int pwr_down_mode;
ad5686_write_func write;
ad5686_read_func read;
bool use_internal_vref;
/*
* DMA (thus cache coherency maintenance) requires the
* transfer buffers to live in their own cache lines.
*/
union {
__be32 d32;
__be16 d16;
u8 d8[4];
} data[3] ____cacheline_aligned;
};
int ad5686_probe(struct device *dev,
enum ad5686_supported_device_ids chip_type,
const char *name, ad5686_write_func write,
ad5686_read_func read);
int ad5686_remove(struct device *dev);
#endif /* __DRIVERS_IIO_DAC_AD5686_H__ */