xref: /openbmc/linux/drivers/iio/adc/ad7606.h (revision a20eefae)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * AD7606 ADC driver
4  *
5  * Copyright 2011 Analog Devices Inc.
6  */
7 
8 #ifndef IIO_ADC_AD7606_H_
9 #define IIO_ADC_AD7606_H_
10 
11 /**
12  * struct ad7606_chip_info - chip specific information
13  * @channels:		channel specification
14  * @num_channels:	number of channels
15  * @oversampling_avail	pointer to the array which stores the available
16  *			oversampling ratios.
17  * @oversampling_num	number of elements stored in oversampling_avail array
18  * @os_req_reset	some devices require a reset to update oversampling
19  * @write_scale_sw	pointer to the function which writes the scale via spi
20 			in software mode
21  * @write_os_sw		pointer to the function which writes the os via spi
22 			in software mode
23  * @sw_mode_config:	pointer to a function which configured the device
24  *			for software mode
25  */
26 struct ad7606_chip_info {
27 	const struct iio_chan_spec	*channels;
28 	unsigned int			num_channels;
29 	const unsigned int		*oversampling_avail;
30 	unsigned int			oversampling_num;
31 	bool				os_req_reset;
32 	int (*write_scale_sw)(struct iio_dev *indio_dev, int ch, int val);
33 	int (*write_os_sw)(struct iio_dev *indio_dev, int val);
34 	int (*sw_mode_config)(struct iio_dev *indio_dev);
35 };
36 
37 /**
38  * struct ad7606_state - driver instance specific data
39  * @dev		pointer to kernel device
40  * @chip_info		entry in the table of chips that describes this device
41  * @reg		regulator info for the the power supply of the device
42  * @bops		bus operations (SPI or parallel)
43  * @range		voltage range selection, selects which scale to apply
44  * @oversampling	oversampling selection
45  * @base_address	address from where to read data in parallel operation
46  * @sw_mode_en		software mode enabled
47  * @scale_avail		pointer to the array which stores the available scales
48  * @num_scales		number of elements stored in the scale_avail array
49  * @oversampling_avail	pointer to the array which stores the available
50  *			oversampling ratios.
51  * @num_os_ratios	number of elements stored in oversampling_avail array
52  * @write_scale		pointer to the function which writes the scale
53  * @write_os		pointer to the function which writes the os
54  * @lock		protect sensor state from concurrent accesses to GPIOs
55  * @gpio_convst	GPIO descriptor for conversion start signal (CONVST)
56  * @gpio_reset		GPIO descriptor for device hard-reset
57  * @gpio_range		GPIO descriptor for range selection
58  * @gpio_standby	GPIO descriptor for stand-by signal (STBY),
59  *			controls power-down mode of device
60  * @gpio_frstdata	GPIO descriptor for reading from device when data
61  *			is being read on the first channel
62  * @gpio_os		GPIO descriptors to control oversampling on the device
63  * @complete		completion to indicate end of conversion
64  * @trig		The IIO trigger associated with the device.
65  * @data		buffer for reading data from the device
66  */
67 struct ad7606_state {
68 	struct device			*dev;
69 	const struct ad7606_chip_info	*chip_info;
70 	struct regulator		*reg;
71 	const struct ad7606_bus_ops	*bops;
72 	unsigned int			range[16];
73 	unsigned int			oversampling;
74 	void __iomem			*base_address;
75 	bool				sw_mode_en;
76 	const unsigned int		*scale_avail;
77 	unsigned int			num_scales;
78 	const unsigned int		*oversampling_avail;
79 	unsigned int			num_os_ratios;
80 	int (*write_scale)(struct iio_dev *indio_dev, int ch, int val);
81 	int (*write_os)(struct iio_dev *indio_dev, int val);
82 
83 	struct mutex			lock; /* protect sensor state */
84 	struct gpio_desc		*gpio_convst;
85 	struct gpio_desc		*gpio_reset;
86 	struct gpio_desc		*gpio_range;
87 	struct gpio_desc		*gpio_standby;
88 	struct gpio_desc		*gpio_frstdata;
89 	struct gpio_descs		*gpio_os;
90 	struct iio_trigger		*trig;
91 	struct completion		completion;
92 
93 	/*
94 	 * DMA (thus cache coherency maintenance) requires the
95 	 * transfer buffers to live in their own cache lines.
96 	 * 16 * 16-bit samples + 64-bit timestamp
97 	 */
98 	unsigned short			data[20] ____cacheline_aligned;
99 };
100 
101 /**
102  * struct ad7606_bus_ops - driver bus operations
103  * @read_block		function pointer for reading blocks of data
104  */
105 struct ad7606_bus_ops {
106 	/* more methods added in future? */
107 	int (*read_block)(struct device *dev, int num, void *data);
108 };
109 
110 int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
111 		 const char *name, unsigned int id,
112 		 const struct ad7606_bus_ops *bops);
113 
114 enum ad7606_supported_device_ids {
115 	ID_AD7605_4,
116 	ID_AD7606_8,
117 	ID_AD7606_6,
118 	ID_AD7606_4,
119 	ID_AD7616,
120 };
121 
122 #ifdef CONFIG_PM_SLEEP
123 extern const struct dev_pm_ops ad7606_pm_ops;
124 #define AD7606_PM_OPS (&ad7606_pm_ops)
125 #else
126 #define AD7606_PM_OPS NULL
127 #endif
128 
129 #endif /* IIO_ADC_AD7606_H_ */
130