linux/drivers/iio/adc/ad7606.h
Jonathan Cameron 6268c6eebb iio: adc: ad7606: Fix alignment for DMA safety
____cacheline_aligned is an insufficient guarantee for non-coherent DMA
on platforms with 128 byte cachelines above L1.  Switch to the updated
IIO_ALIGN definition.

Update the comment to reflect the fact DMA safety 'may' require
separate cachelines.

Fixes: 7989b4bb23 ("iio: adc: ad7616: Add support for AD7616 ADC")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220508175712.647246-15-jic23@kernel.org
2022-06-14 11:53:12 +01:00

173 lines
5.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* AD7606 ADC driver
*
* Copyright 2011 Analog Devices Inc.
*/
#ifndef IIO_ADC_AD7606_H_
#define IIO_ADC_AD7606_H_
#define AD760X_CHANNEL(num, mask_sep, mask_type, mask_all) { \
.type = IIO_VOLTAGE, \
.indexed = 1, \
.channel = num, \
.address = num, \
.info_mask_separate = mask_sep, \
.info_mask_shared_by_type = mask_type, \
.info_mask_shared_by_all = mask_all, \
.scan_index = num, \
.scan_type = { \
.sign = 's', \
.realbits = 16, \
.storagebits = 16, \
.endianness = IIO_CPU, \
}, \
}
#define AD7605_CHANNEL(num) \
AD760X_CHANNEL(num, BIT(IIO_CHAN_INFO_RAW), \
BIT(IIO_CHAN_INFO_SCALE), 0)
#define AD7606_CHANNEL(num) \
AD760X_CHANNEL(num, BIT(IIO_CHAN_INFO_RAW), \
BIT(IIO_CHAN_INFO_SCALE), \
BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO))
#define AD7616_CHANNEL(num) \
AD760X_CHANNEL(num, BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),\
0, BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO))
/**
* struct ad7606_chip_info - chip specific information
* @channels: channel specification
* @num_channels: number of channels
* @oversampling_avail pointer to the array which stores the available
* oversampling ratios.
* @oversampling_num number of elements stored in oversampling_avail array
* @os_req_reset some devices require a reset to update oversampling
* @init_delay_ms required delay in miliseconds for initialization
* after a restart
*/
struct ad7606_chip_info {
const struct iio_chan_spec *channels;
unsigned int num_channels;
const unsigned int *oversampling_avail;
unsigned int oversampling_num;
bool os_req_reset;
unsigned long init_delay_ms;
};
/**
* struct ad7606_state - driver instance specific data
* @dev pointer to kernel device
* @chip_info entry in the table of chips that describes this device
* @reg regulator info for the power supply of the device
* @bops bus operations (SPI or parallel)
* @range voltage range selection, selects which scale to apply
* @oversampling oversampling selection
* @base_address address from where to read data in parallel operation
* @sw_mode_en software mode enabled
* @scale_avail pointer to the array which stores the available scales
* @num_scales number of elements stored in the scale_avail array
* @oversampling_avail pointer to the array which stores the available
* oversampling ratios.
* @num_os_ratios number of elements stored in oversampling_avail array
* @write_scale pointer to the function which writes the scale
* @write_os pointer to the function which writes the os
* @lock protect sensor state from concurrent accesses to GPIOs
* @gpio_convst GPIO descriptor for conversion start signal (CONVST)
* @gpio_reset GPIO descriptor for device hard-reset
* @gpio_range GPIO descriptor for range selection
* @gpio_standby GPIO descriptor for stand-by signal (STBY),
* controls power-down mode of device
* @gpio_frstdata GPIO descriptor for reading from device when data
* is being read on the first channel
* @gpio_os GPIO descriptors to control oversampling on the device
* @complete completion to indicate end of conversion
* @trig The IIO trigger associated with the device.
* @data buffer for reading data from the device
* @d16 be16 buffer for reading data from the device
*/
struct ad7606_state {
struct device *dev;
const struct ad7606_chip_info *chip_info;
struct regulator *reg;
const struct ad7606_bus_ops *bops;
unsigned int range[16];
unsigned int oversampling;
void __iomem *base_address;
bool sw_mode_en;
const unsigned int *scale_avail;
unsigned int num_scales;
const unsigned int *oversampling_avail;
unsigned int num_os_ratios;
int (*write_scale)(struct iio_dev *indio_dev, int ch, int val);
int (*write_os)(struct iio_dev *indio_dev, int val);
struct mutex lock; /* protect sensor state */
struct gpio_desc *gpio_convst;
struct gpio_desc *gpio_reset;
struct gpio_desc *gpio_range;
struct gpio_desc *gpio_standby;
struct gpio_desc *gpio_frstdata;
struct gpio_descs *gpio_os;
struct iio_trigger *trig;
struct completion completion;
/*
* DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
* 16 * 16-bit samples + 64-bit timestamp
*/
unsigned short data[20] __aligned(IIO_DMA_MINALIGN);
__be16 d16[2];
};
/**
* struct ad7606_bus_ops - driver bus operations
* @read_block function pointer for reading blocks of data
* @sw_mode_config: pointer to a function which configured the device
* for software mode
* @reg_read function pointer for reading spi register
* @reg_write function pointer for writing spi register
* @write_mask function pointer for write spi register with mask
* @rd_wr_cmd pointer to the function which calculates the spi address
*/
struct ad7606_bus_ops {
/* more methods added in future? */
int (*read_block)(struct device *dev, int num, void *data);
int (*sw_mode_config)(struct iio_dev *indio_dev);
int (*reg_read)(struct ad7606_state *st, unsigned int addr);
int (*reg_write)(struct ad7606_state *st,
unsigned int addr,
unsigned int val);
int (*write_mask)(struct ad7606_state *st,
unsigned int addr,
unsigned long mask,
unsigned int val);
u16 (*rd_wr_cmd)(int addr, char isWriteOp);
};
int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
const char *name, unsigned int id,
const struct ad7606_bus_ops *bops);
enum ad7606_supported_device_ids {
ID_AD7605_4,
ID_AD7606_8,
ID_AD7606_6,
ID_AD7606_4,
ID_AD7606B,
ID_AD7616,
};
#ifdef CONFIG_PM_SLEEP
extern const struct dev_pm_ops ad7606_pm_ops;
#define AD7606_PM_OPS (&ad7606_pm_ops)
#else
#define AD7606_PM_OPS NULL
#endif
#endif /* IIO_ADC_AD7606_H_ */