106 lines
2.7 KiB
C
106 lines
2.7 KiB
C
/*
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* AD7887 SPI ADC driver
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*
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* Copyright 2010 Analog Devices Inc.
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*
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* Licensed under the GPL-2 or later.
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*/
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#ifndef IIO_ADC_AD7887_H_
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#define IIO_ADC_AD7887_H_
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#define AD7887_REF_DIS (1 << 5) /* on-chip reference disable */
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#define AD7887_DUAL (1 << 4) /* dual-channel mode */
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#define AD7887_CH_AIN1 (1 << 3) /* convert on channel 1, DUAL=1 */
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#define AD7887_CH_AIN0 (0 << 3) /* convert on channel 0, DUAL=0,1 */
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#define AD7887_PM_MODE1 (0) /* CS based shutdown */
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#define AD7887_PM_MODE2 (1) /* full on */
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#define AD7887_PM_MODE3 (2) /* auto shutdown after conversion */
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#define AD7887_PM_MODE4 (3) /* standby mode */
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enum ad7887_channels {
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AD7887_CH0,
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AD7887_CH0_CH1,
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AD7887_CH1,
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};
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#define RES_MASK(bits) ((1 << (bits)) - 1) /* TODO: move this into a common header */
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/*
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* TODO: struct ad7887_platform_data needs to go into include/linux/iio
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*/
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struct ad7887_platform_data {
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/* External Vref voltage applied */
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u16 vref_mv;
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/*
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* AD7887:
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* In single channel mode en_dual = flase, AIN1/Vref pins assumes its
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* Vref function. In dual channel mode en_dual = true, AIN1 becomes the
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* second input channel, and Vref is internally connected to Vdd.
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*/
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bool en_dual;
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/*
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* AD7887:
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* use_onchip_ref = true, the Vref is internally connected to the 2.500V
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* Voltage reference. If use_onchip_ref = false, the reference voltage
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* is supplied by AIN1/Vref
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*/
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bool use_onchip_ref;
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};
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/**
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* struct ad7887_chip_info - chip specifc information
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* @int_vref_mv: the internal reference voltage
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* @channel: channel specification
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*/
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struct ad7887_chip_info {
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u16 int_vref_mv;
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struct iio_chan_spec channel[3];
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};
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struct ad7887_state {
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struct spi_device *spi;
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const struct ad7887_chip_info *chip_info;
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struct regulator *reg;
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size_t d_size;
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u16 int_vref_mv;
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struct spi_transfer xfer[4];
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struct spi_message msg[3];
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struct spi_message *ring_msg;
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unsigned char tx_cmd_buf[8];
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/*
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* DMA (thus cache coherency maintenance) requires the
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* transfer buffers to live in their own cache lines.
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*/
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unsigned char data[4] ____cacheline_aligned;
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};
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enum ad7887_supported_device_ids {
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ID_AD7887
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};
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#ifdef CONFIG_IIO_RING_BUFFER
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int ad7887_scan_from_ring(struct ad7887_state *st, long mask);
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int ad7887_register_ring_funcs_and_init(struct iio_dev *indio_dev);
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void ad7887_ring_cleanup(struct iio_dev *indio_dev);
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#else /* CONFIG_IIO_RING_BUFFER */
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static inline int ad7887_scan_from_ring(struct ad7887_state *st, long mask)
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{
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return 0;
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}
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static inline int
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ad7887_register_ring_funcs_and_init(struct iio_dev *indio_dev)
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{
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return 0;
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}
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static inline void ad7887_ring_cleanup(struct iio_dev *indio_dev)
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{
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}
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#endif /* CONFIG_IIO_RING_BUFFER */
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#endif /* IIO_ADC_AD7887_H_ */
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