77 lines
2.0 KiB
C
77 lines
2.0 KiB
C
/*
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* AD7298 SPI ADC driver
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*
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* Copyright 2011 Analog Devices Inc.
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*
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* Licensed under the GPL-2.
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*/
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#ifndef IIO_ADC_AD7298_H_
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#define IIO_ADC_AD7298_H_
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#define AD7298_WRITE (1 << 15) /* write to the control register */
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#define AD7298_REPEAT (1 << 14) /* repeated conversion enable */
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#define AD7298_CH(x) (1 << (13 - (x))) /* channel select */
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#define AD7298_TSENSE (1 << 5) /* temperature conversion enable */
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#define AD7298_EXTREF (1 << 2) /* external reference enable */
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#define AD7298_TAVG (1 << 1) /* temperature sensor averaging enable */
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#define AD7298_PDD (1 << 0) /* partial power down enable */
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#define AD7298_MAX_CHAN 8
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#define AD7298_BITS 12
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#define AD7298_STORAGE_BITS 16
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#define AD7298_INTREF_mV 2500
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#define AD7298_CH_TEMP 9
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#define RES_MASK(bits) ((1 << (bits)) - 1)
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/*
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* TODO: struct ad7298_platform_data needs to go into include/linux/iio
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*/
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struct ad7298_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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struct ad7298_state {
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struct spi_device *spi;
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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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unsigned ext_ref;
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struct spi_transfer ring_xfer[10];
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struct spi_transfer scan_single_xfer[3];
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struct spi_message ring_msg;
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struct spi_message scan_single_msg;
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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 short rx_buf[8] ____cacheline_aligned;
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unsigned short tx_buf[2];
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};
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#ifdef CONFIG_IIO_RING_BUFFER
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int ad7298_scan_from_ring(struct iio_dev *indio_dev, long ch);
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int ad7298_register_ring_funcs_and_init(struct iio_dev *indio_dev);
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void ad7298_ring_cleanup(struct iio_dev *indio_dev);
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#else /* CONFIG_IIO_RING_BUFFER */
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static inline int ad7298_scan_from_ring(struct iio_dev *indio_dev, long ch)
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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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ad7298_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 ad7298_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_AD7298_H_ */
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