 fc52692c49
			
		
	
	
	fc52692c49
	
	
	
		
			
			CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			408 lines
		
	
	
	
		
			9.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			408 lines
		
	
	
	
		
			9.5 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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| 
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| #include <linux/device.h>
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| #include <linux/kernel.h>
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| #include <linux/slab.h>
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| #include <linux/sysfs.h>
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| #include <linux/spi/spi.h>
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| #include <linux/regulator/consumer.h>
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| #include <linux/err.h>
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| #include <linux/delay.h>
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| #include <linux/module.h>
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| #include <linux/interrupt.h>
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| 
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| #include <linux/iio/iio.h>
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| #include <linux/iio/sysfs.h>
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| #include <linux/iio/buffer.h>
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| #include <linux/iio/trigger_consumer.h>
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| #include <linux/iio/triggered_buffer.h>
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| 
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| #include <linux/platform_data/ad7298.h>
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| 
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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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| 
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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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| 
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| #define AD7298_CH_TEMP		9
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| 
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| #define RES_MASK(bits)	((1 << (bits)) - 1)
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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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| 	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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| 	__be16				rx_buf[12] ____cacheline_aligned;
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| 	__be16				tx_buf[2];
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| };
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| 
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| #define AD7298_V_CHAN(index)						\
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| 	{								\
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| 		.type = IIO_VOLTAGE,					\
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| 		.indexed = 1,						\
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| 		.channel = index,					\
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| 		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |		\
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| 		IIO_CHAN_INFO_SCALE_SHARED_BIT,				\
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| 		.address = index,					\
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| 		.scan_index = index,					\
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| 		.scan_type = {						\
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| 			.sign = 'u',					\
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| 			.realbits = 12,					\
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| 			.storagebits = 16,				\
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| 			.endianness = IIO_BE,				\
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| 		},							\
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| 	}
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| 
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| static const struct iio_chan_spec ad7298_channels[] = {
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| 	{
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| 		.type = IIO_TEMP,
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| 		.indexed = 1,
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| 		.channel = 0,
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| 		.info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT |
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| 			IIO_CHAN_INFO_SCALE_SEPARATE_BIT |
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| 			IIO_CHAN_INFO_OFFSET_SEPARATE_BIT,
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| 		.address = AD7298_CH_TEMP,
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| 		.scan_index = -1,
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| 		.scan_type = {
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| 			.sign = 's',
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| 			.realbits = 32,
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| 			.storagebits = 32,
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| 		},
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| 	},
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| 	AD7298_V_CHAN(0),
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| 	AD7298_V_CHAN(1),
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| 	AD7298_V_CHAN(2),
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| 	AD7298_V_CHAN(3),
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| 	AD7298_V_CHAN(4),
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| 	AD7298_V_CHAN(5),
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| 	AD7298_V_CHAN(6),
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| 	AD7298_V_CHAN(7),
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| 	IIO_CHAN_SOFT_TIMESTAMP(8),
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| };
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| 
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| /**
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|  * ad7298_update_scan_mode() setup the spi transfer buffer for the new scan mask
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|  **/
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| static int ad7298_update_scan_mode(struct iio_dev *indio_dev,
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| 	const unsigned long *active_scan_mask)
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| {
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| 	struct ad7298_state *st = iio_priv(indio_dev);
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| 	int i, m;
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| 	unsigned short command;
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| 	int scan_count;
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| 
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| 	/* Now compute overall size */
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| 	scan_count = bitmap_weight(active_scan_mask, indio_dev->masklength);
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| 
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| 	command = AD7298_WRITE | st->ext_ref;
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| 
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| 	for (i = 0, m = AD7298_CH(0); i < AD7298_MAX_CHAN; i++, m >>= 1)
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| 		if (test_bit(i, active_scan_mask))
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| 			command |= m;
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| 
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| 	st->tx_buf[0] = cpu_to_be16(command);
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| 
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| 	/* build spi ring message */
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| 	st->ring_xfer[0].tx_buf = &st->tx_buf[0];
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| 	st->ring_xfer[0].len = 2;
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| 	st->ring_xfer[0].cs_change = 1;
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| 	st->ring_xfer[1].tx_buf = &st->tx_buf[1];
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| 	st->ring_xfer[1].len = 2;
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| 	st->ring_xfer[1].cs_change = 1;
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| 
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| 	spi_message_init(&st->ring_msg);
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| 	spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg);
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| 	spi_message_add_tail(&st->ring_xfer[1], &st->ring_msg);
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| 
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| 	for (i = 0; i < scan_count; i++) {
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| 		st->ring_xfer[i + 2].rx_buf = &st->rx_buf[i];
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| 		st->ring_xfer[i + 2].len = 2;
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| 		st->ring_xfer[i + 2].cs_change = 1;
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| 		spi_message_add_tail(&st->ring_xfer[i + 2], &st->ring_msg);
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| 	}
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| 	/* make sure last transfer cs_change is not set */
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| 	st->ring_xfer[i + 1].cs_change = 0;
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| 
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| 	return 0;
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| }
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| 
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| /**
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|  * ad7298_trigger_handler() bh of trigger launched polling to ring buffer
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|  *
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|  * Currently there is no option in this driver to disable the saving of
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|  * timestamps within the ring.
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|  **/
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| static irqreturn_t ad7298_trigger_handler(int irq, void *p)
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| {
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| 	struct iio_poll_func *pf = p;
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| 	struct iio_dev *indio_dev = pf->indio_dev;
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| 	struct ad7298_state *st = iio_priv(indio_dev);
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| 	s64 time_ns = 0;
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| 	int b_sent;
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| 
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| 	b_sent = spi_sync(st->spi, &st->ring_msg);
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| 	if (b_sent)
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| 		goto done;
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| 
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| 	if (indio_dev->scan_timestamp) {
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| 		time_ns = iio_get_time_ns();
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| 		memcpy((u8 *)st->rx_buf + indio_dev->scan_bytes - sizeof(s64),
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| 			&time_ns, sizeof(time_ns));
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| 	}
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| 
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| 	iio_push_to_buffers(indio_dev, (u8 *)st->rx_buf);
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| 
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| done:
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| 	iio_trigger_notify_done(indio_dev->trig);
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| 
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| 	return IRQ_HANDLED;
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| }
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| 
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| static int ad7298_scan_direct(struct ad7298_state *st, unsigned ch)
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| {
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| 	int ret;
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| 	st->tx_buf[0] = cpu_to_be16(AD7298_WRITE | st->ext_ref |
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| 				   (AD7298_CH(0) >> ch));
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| 
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| 	ret = spi_sync(st->spi, &st->scan_single_msg);
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| 	if (ret)
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| 		return ret;
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| 
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| 	return be16_to_cpu(st->rx_buf[0]);
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| }
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| 
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| static int ad7298_scan_temp(struct ad7298_state *st, int *val)
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| {
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| 	int ret;
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| 	__be16 buf;
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| 
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| 	buf = cpu_to_be16(AD7298_WRITE | AD7298_TSENSE |
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| 			  AD7298_TAVG | st->ext_ref);
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| 
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| 	ret = spi_write(st->spi, (u8 *)&buf, 2);
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| 	if (ret)
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| 		return ret;
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| 
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| 	buf = cpu_to_be16(0);
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| 
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| 	ret = spi_write(st->spi, (u8 *)&buf, 2);
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| 	if (ret)
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| 		return ret;
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| 
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| 	usleep_range(101, 1000); /* sleep > 100us */
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| 
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| 	ret = spi_read(st->spi, (u8 *)&buf, 2);
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| 	if (ret)
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| 		return ret;
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| 
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| 	*val = sign_extend32(be16_to_cpu(buf), 11);
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| 
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| 	return 0;
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| }
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| 
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| static int ad7298_get_ref_voltage(struct ad7298_state *st)
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| {
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| 	int vref;
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| 
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| 	if (st->ext_ref) {
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| 		vref = regulator_get_voltage(st->reg);
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| 		if (vref < 0)
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| 			return vref;
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| 
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| 		return vref / 1000;
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| 	} else {
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| 		return AD7298_INTREF_mV;
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| 	}
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| }
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| 
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| static int ad7298_read_raw(struct iio_dev *indio_dev,
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| 			   struct iio_chan_spec const *chan,
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| 			   int *val,
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| 			   int *val2,
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| 			   long m)
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| {
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| 	int ret;
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| 	struct ad7298_state *st = iio_priv(indio_dev);
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| 
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| 	switch (m) {
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| 	case IIO_CHAN_INFO_RAW:
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| 		mutex_lock(&indio_dev->mlock);
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| 		if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
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| 			ret = -EBUSY;
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| 		} else {
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| 			if (chan->address == AD7298_CH_TEMP)
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| 				ret = ad7298_scan_temp(st, val);
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| 			else
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| 				ret = ad7298_scan_direct(st, chan->address);
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| 		}
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| 		mutex_unlock(&indio_dev->mlock);
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| 
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| 		if (ret < 0)
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| 			return ret;
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| 
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| 		if (chan->address != AD7298_CH_TEMP)
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| 			*val = ret & RES_MASK(AD7298_BITS);
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| 
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| 		return IIO_VAL_INT;
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| 	case IIO_CHAN_INFO_SCALE:
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| 		switch (chan->type) {
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| 		case IIO_VOLTAGE:
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| 			*val = ad7298_get_ref_voltage(st);
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| 			*val2 = chan->scan_type.realbits;
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| 			return IIO_VAL_FRACTIONAL_LOG2;
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| 		case IIO_TEMP:
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| 			*val = ad7298_get_ref_voltage(st);
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| 			*val2 = 10;
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| 			return IIO_VAL_FRACTIONAL;
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| 		default:
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| 			return -EINVAL;
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| 		}
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| 	case IIO_CHAN_INFO_OFFSET:
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| 		*val = 1093 - 2732500 / ad7298_get_ref_voltage(st);
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| 		return IIO_VAL_INT;
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| 	}
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| 	return -EINVAL;
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| }
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| 
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| static const struct iio_info ad7298_info = {
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| 	.read_raw = &ad7298_read_raw,
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| 	.update_scan_mode = ad7298_update_scan_mode,
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| 	.driver_module = THIS_MODULE,
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| };
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| 
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| static int ad7298_probe(struct spi_device *spi)
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| {
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| 	struct ad7298_platform_data *pdata = spi->dev.platform_data;
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| 	struct ad7298_state *st;
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| 	struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
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| 	int ret;
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| 
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| 	if (indio_dev == NULL)
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| 		return -ENOMEM;
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| 
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| 	st = iio_priv(indio_dev);
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| 
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| 	if (pdata && pdata->ext_ref)
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| 		st->ext_ref = AD7298_EXTREF;
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| 
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| 	if (st->ext_ref) {
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| 		st->reg = regulator_get(&spi->dev, "vref");
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| 		if (IS_ERR(st->reg)) {
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| 			ret = PTR_ERR(st->reg);
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| 			goto error_free;
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| 		}
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| 		ret = regulator_enable(st->reg);
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| 		if (ret)
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| 			goto error_put_reg;
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| 	}
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| 
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| 	spi_set_drvdata(spi, indio_dev);
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| 
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| 	st->spi = spi;
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| 
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| 	indio_dev->name = spi_get_device_id(spi)->name;
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| 	indio_dev->dev.parent = &spi->dev;
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| 	indio_dev->modes = INDIO_DIRECT_MODE;
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| 	indio_dev->channels = ad7298_channels;
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| 	indio_dev->num_channels = ARRAY_SIZE(ad7298_channels);
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| 	indio_dev->info = &ad7298_info;
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| 
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| 	/* Setup default message */
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| 
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| 	st->scan_single_xfer[0].tx_buf = &st->tx_buf[0];
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| 	st->scan_single_xfer[0].len = 2;
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| 	st->scan_single_xfer[0].cs_change = 1;
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| 	st->scan_single_xfer[1].tx_buf = &st->tx_buf[1];
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| 	st->scan_single_xfer[1].len = 2;
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| 	st->scan_single_xfer[1].cs_change = 1;
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| 	st->scan_single_xfer[2].rx_buf = &st->rx_buf[0];
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| 	st->scan_single_xfer[2].len = 2;
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| 
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| 	spi_message_init(&st->scan_single_msg);
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| 	spi_message_add_tail(&st->scan_single_xfer[0], &st->scan_single_msg);
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| 	spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
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| 	spi_message_add_tail(&st->scan_single_xfer[2], &st->scan_single_msg);
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| 
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| 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
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| 			&ad7298_trigger_handler, NULL);
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| 	if (ret)
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| 		goto error_disable_reg;
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| 
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| 	ret = iio_device_register(indio_dev);
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| 	if (ret)
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| 		goto error_cleanup_ring;
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| 
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| 	return 0;
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| 
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| error_cleanup_ring:
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| 	iio_triggered_buffer_cleanup(indio_dev);
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| error_disable_reg:
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| 	if (st->ext_ref)
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| 		regulator_disable(st->reg);
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| error_put_reg:
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| 	if (st->ext_ref)
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| 		regulator_put(st->reg);
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| error_free:
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| 	iio_device_free(indio_dev);
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| 
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| 	return ret;
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| }
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| 
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| static int ad7298_remove(struct spi_device *spi)
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| {
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| 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
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| 	struct ad7298_state *st = iio_priv(indio_dev);
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| 
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| 	iio_device_unregister(indio_dev);
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| 	iio_triggered_buffer_cleanup(indio_dev);
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| 	if (st->ext_ref) {
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| 		regulator_disable(st->reg);
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| 		regulator_put(st->reg);
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| 	}
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| 	iio_device_free(indio_dev);
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| 
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| 	return 0;
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| }
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| 
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| static const struct spi_device_id ad7298_id[] = {
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| 	{"ad7298", 0},
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| 	{}
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| };
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| MODULE_DEVICE_TABLE(spi, ad7298_id);
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| 
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| static struct spi_driver ad7298_driver = {
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| 	.driver = {
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| 		.name	= "ad7298",
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| 		.owner	= THIS_MODULE,
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| 	},
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| 	.probe		= ad7298_probe,
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| 	.remove		= ad7298_remove,
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| 	.id_table	= ad7298_id,
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| };
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| module_spi_driver(ad7298_driver);
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| 
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| MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
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| MODULE_DESCRIPTION("Analog Devices AD7298 ADC");
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| MODULE_LICENSE("GPL v2");
 |