Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / drivers / staging / iio / adc / ad7887.h

diff --git a/drivers/staging/iio/adc/ad7887.h b/drivers/staging/iio/adc/ad7887.h
new file mode 100644 (file)
index 0000000..8c2a218
--- /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_ */