| Michael Hennerich | 7c31b98 | 2011-02-24 12:32:45 +0100 | [diff] [blame^] | 1 | /* |
| 2 | * AD7298 SPI ADC driver |
| 3 | * |
| 4 | * Copyright 2011 Analog Devices Inc. |
| 5 | * |
| 6 | * Licensed under the GPL-2. |
| 7 | */ |
| 8 | |
| 9 | #ifndef IIO_ADC_AD7298_H_ |
| 10 | #define IIO_ADC_AD7298_H_ |
| 11 | |
| 12 | #define AD7298_WRITE (1 << 15) /* write to the control register */ |
| 13 | #define AD7298_REPEAT (1 << 14) /* repeated conversion enable */ |
| 14 | #define AD7298_CH(x) (1 << (13 - (x))) /* channel select */ |
| 15 | #define AD7298_TSENSE (1 << 5) /* temperature conversion enable */ |
| 16 | #define AD7298_EXTREF (1 << 2) /* external reference enable */ |
| 17 | #define AD7298_TAVG (1 << 1) /* temperature sensor averaging enable */ |
| 18 | #define AD7298_PDD (1 << 0) /* partial power down enable */ |
| 19 | |
| 20 | #define AD7298_CH_MASK (AD7298_CH0 | AD7298_CH1 | AD7298_CH2 | AD7298_CH3 | \ |
| 21 | AD7298_CH4 | AD7298_CH5 | AD7298_CH6 | AD7298_CH7) |
| 22 | |
| 23 | #define AD7298_MAX_CHAN 8 |
| 24 | #define AD7298_BITS 12 |
| 25 | #define AD7298_STORAGE_BITS 16 |
| 26 | #define AD7298_INTREF_mV 2500 |
| 27 | |
| 28 | #define RES_MASK(bits) ((1 << (bits)) - 1) |
| 29 | |
| 30 | /* |
| 31 | * TODO: struct ad7298_platform_data needs to go into include/linux/iio |
| 32 | */ |
| 33 | |
| 34 | struct ad7298_platform_data { |
| 35 | /* External Vref voltage applied */ |
| 36 | u16 vref_mv; |
| 37 | }; |
| 38 | |
| 39 | struct ad7298_state { |
| 40 | struct iio_dev *indio_dev; |
| 41 | struct spi_device *spi; |
| 42 | struct regulator *reg; |
| 43 | struct work_struct poll_work; |
| 44 | atomic_t protect_ring; |
| 45 | size_t d_size; |
| 46 | u16 int_vref_mv; |
| 47 | unsigned ext_ref; |
| 48 | struct spi_transfer ring_xfer[10]; |
| 49 | struct spi_transfer scan_single_xfer[3]; |
| 50 | struct spi_message ring_msg; |
| 51 | struct spi_message scan_single_msg; |
| 52 | /* |
| 53 | * DMA (thus cache coherency maintenance) requires the |
| 54 | * transfer buffers to live in their own cache lines. |
| 55 | */ |
| 56 | unsigned short rx_buf[8] ____cacheline_aligned; |
| 57 | unsigned short tx_buf[2]; |
| 58 | }; |
| 59 | |
| 60 | #ifdef CONFIG_IIO_RING_BUFFER |
| 61 | int ad7298_scan_from_ring(struct ad7298_state *st, long ch); |
| 62 | int ad7298_register_ring_funcs_and_init(struct iio_dev *indio_dev); |
| 63 | void ad7298_ring_cleanup(struct iio_dev *indio_dev); |
| 64 | #else /* CONFIG_IIO_RING_BUFFER */ |
| 65 | static inline int ad7298_scan_from_ring(struct ad7298_state *st, long ch) |
| 66 | { |
| 67 | return 0; |
| 68 | } |
| 69 | |
| 70 | static inline int |
| 71 | ad7298_register_ring_funcs_and_init(struct iio_dev *indio_dev) |
| 72 | { |
| 73 | return 0; |
| 74 | } |
| 75 | |
| 76 | static inline void ad7298_ring_cleanup(struct iio_dev *indio_dev) |
| 77 | { |
| 78 | } |
| 79 | #endif /* CONFIG_IIO_RING_BUFFER */ |
| 80 | #endif /* IIO_ADC_AD7298_H_ */ |