1 files changed, 105 insertions, 0 deletions
diff --git a/drivers/staging/iio/adc/ad7887.h b/drivers/staging/iio/adc/ad7887.h
new file mode 100644
index 000000000000..8c2a218c9496
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7887.h
@@ -0,0 +1,105 @@
+/*
+ * AD7887 SPI ADC driver
+ *
+ * Copyright 2010 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+#ifndef IIO_ADC_AD7887_H_
+#define IIO_ADC_AD7887_H_
+
+#define AD7887_REF_DIS		(1 << 5) /* on-chip reference disable */
+#define AD7887_DUAL		(1 << 4) /* dual-channel mode */
+#define AD7887_CH_AIN1		(1 << 3) /* convert on channel 1, DUAL=1 */
+#define AD7887_CH_AIN0		(0 << 3) /* convert on channel 0, DUAL=0,1 */
+#define AD7887_PM_MODE1		(0)	 /* CS based shutdown */
+#define AD7887_PM_MODE2		(1)	 /* full on */
+#define AD7887_PM_MODE3		(2)	 /* auto shutdown after conversion */
+#define AD7887_PM_MODE4		(3)	 /* standby mode */
+
+enum ad7887_channels {
+	AD7887_CH0,
+	AD7887_CH0_CH1,
+	AD7887_CH1,
+};
+
+#define RES_MASK(bits)	((1 << (bits)) - 1) /* TODO: move this into a common header */
+
+/*
+ * TODO: struct ad7887_platform_data needs to go into include/linux/iio
+ */
+
+struct ad7887_platform_data {
+	/* External Vref voltage applied */
+	u16				vref_mv;
+	/*
+	 * AD7887:
+	 * In single channel mode en_dual = flase, AIN1/Vref pins assumes its
+	 * Vref function. In dual channel mode en_dual = true, AIN1 becomes the
+	 * second input channel, and Vref is internally connected to Vdd.
+	 */
+	bool				en_dual;
+	/*
+	 * AD7887:
+	 * use_onchip_ref = true, the Vref is internally connected to the 2.500V
+	 * Voltage reference. If use_onchip_ref = false, the reference voltage
+	 * is supplied by AIN1/Vref
+	 */
+	bool				use_onchip_ref;
+};
+
+struct ad7887_chip_info {
+	u8				bits;		/* number of ADC bits */
+	u8				storagebits;	/* number of bits read from the ADC */
+	u8				left_shift;	/* number of bits the sample must be shifted */
+	char				sign;		/* [s]igned or [u]nsigned */
+	u16				int_vref_mv;	/* internal reference voltage */
+};
+
+struct ad7887_state {
+	struct iio_dev			*indio_dev;
+	struct spi_device		*spi;
+	const struct ad7887_chip_info	*chip_info;
+	struct regulator		*reg;
+	struct work_struct		poll_work;
+	atomic_t			protect_ring;
+	u16				int_vref_mv;
+	bool				en_dual;
+	struct spi_transfer		xfer[4];
+	struct spi_message		msg[3];
+	struct spi_message		*ring_msg;
+	unsigned char			tx_cmd_buf[8];
+
+	/*
+	 * DMA (thus cache coherency maintenance) requires the
+	 * transfer buffers to live in their own cache lines.
+	 */
+
+	unsigned char			data[4] ____cacheline_aligned;
+};
+
+enum ad7887_supported_device_ids {
+	ID_AD7887
+};
+
+#ifdef CONFIG_IIO_RING_BUFFER
+int ad7887_scan_from_ring(struct ad7887_state *st, long mask);
+int ad7887_register_ring_funcs_and_init(struct iio_dev *indio_dev);
+void ad7887_ring_cleanup(struct iio_dev *indio_dev);
+#else /* CONFIG_IIO_RING_BUFFER */
+static inline int ad7887_scan_from_ring(struct ad7887_state *st, long mask)
+{
+	return 0;
+}
+
+static inline int
+ad7887_register_ring_funcs_and_init(struct iio_dev *indio_dev)
+{
+	return 0;
+}
+
+static inline void ad7887_ring_cleanup(struct iio_dev *indio_dev)
+{
+}
+#endif /* CONFIG_IIO_RING_BUFFER */
+#endif /* IIO_ADC_AD7887_H_ */