Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / staging / iio / adc / ad7780.h

diff --git a/kernel/drivers/staging/iio/adc/ad7780.h b/kernel/drivers/staging/iio/adc/ad7780.h
new file mode 100644 (file)
index 0000000..67e511c
--- /dev/null
+++ b/kernel/drivers/staging/iio/adc/ad7780.h
@@ -0,0 +1,30 @@
+/*
+ * AD7780/AD7781 SPI ADC driver
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+#ifndef IIO_ADC_AD7780_H_
+#define IIO_ADC_AD7780_H_
+
+/*
+ * TODO: struct ad7780_platform_data needs to go into include/linux/iio
+ */
+
+/* NOTE:
+ * The AD7780 doesn't feature a dedicated SPI chip select, in addition it
+ * features a dual use data out ready DOUT/RDY output.
+ * In order to avoid contentions on the SPI bus, it's therefore necessary
+ * to use spi bus locking combined with a dedicated GPIO to control the
+ * power down reset signal of the AD7780.
+ *
+ * The DOUT/RDY output must also be wired to an interrupt capable GPIO.
+ */
+
+struct ad7780_platform_data {
+       u16                             vref_mv;
+       int                             gpio_pdrst;
+};
+
+#endif /* IIO_ADC_AD7780_H_ */