726 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			726 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
 | |
| /*
 | |
|  * Texas Instruments ADS7950 SPI ADC driver
 | |
|  *
 | |
|  * Copyright 2016 David Lechner <david@lechnology.com>
 | |
|  *
 | |
|  * Based on iio/ad7923.c:
 | |
|  * Copyright 2011 Analog Devices Inc
 | |
|  * Copyright 2012 CS Systemes d'Information
 | |
|  *
 | |
|  * And also on hwmon/ads79xx.c
 | |
|  * Copyright (C) 2013 Texas Instruments Incorporated - https://www.ti.com/
 | |
|  *	Nishanth Menon
 | |
|  */
 | |
| 
 | |
| #include <linux/acpi.h>
 | |
| #include <linux/bitops.h>
 | |
| #include <linux/device.h>
 | |
| #include <linux/err.h>
 | |
| #include <linux/gpio/driver.h>
 | |
| #include <linux/interrupt.h>
 | |
| #include <linux/kernel.h>
 | |
| #include <linux/module.h>
 | |
| #include <linux/regulator/consumer.h>
 | |
| #include <linux/slab.h>
 | |
| #include <linux/spi/spi.h>
 | |
| 
 | |
| #include <linux/iio/buffer.h>
 | |
| #include <linux/iio/iio.h>
 | |
| #include <linux/iio/sysfs.h>
 | |
| #include <linux/iio/trigger_consumer.h>
 | |
| #include <linux/iio/triggered_buffer.h>
 | |
| 
 | |
| /*
 | |
|  * In case of ACPI, we use the 5000 mV as default for the reference pin.
 | |
|  * Device tree users encode that via the vref-supply regulator.
 | |
|  */
 | |
| #define TI_ADS7950_VA_MV_ACPI_DEFAULT	5000
 | |
| 
 | |
| #define TI_ADS7950_CR_GPIO	BIT(14)
 | |
| #define TI_ADS7950_CR_MANUAL	BIT(12)
 | |
| #define TI_ADS7950_CR_WRITE	BIT(11)
 | |
| #define TI_ADS7950_CR_CHAN(ch)	((ch) << 7)
 | |
| #define TI_ADS7950_CR_RANGE_5V	BIT(6)
 | |
| #define TI_ADS7950_CR_GPIO_DATA	BIT(4)
 | |
| 
 | |
| #define TI_ADS7950_MAX_CHAN	16
 | |
| #define TI_ADS7950_NUM_GPIOS	4
 | |
| 
 | |
| #define TI_ADS7950_TIMESTAMP_SIZE (sizeof(int64_t) / sizeof(__be16))
 | |
| 
 | |
| /* val = value, dec = left shift, bits = number of bits of the mask */
 | |
| #define TI_ADS7950_EXTRACT(val, dec, bits) \
 | |
| 	(((val) >> (dec)) & ((1 << (bits)) - 1))
 | |
| 
 | |
| #define TI_ADS7950_MAN_CMD(cmd)         (TI_ADS7950_CR_MANUAL | (cmd))
 | |
| #define TI_ADS7950_GPIO_CMD(cmd)        (TI_ADS7950_CR_GPIO | (cmd))
 | |
| 
 | |
| /* Manual mode configuration */
 | |
| #define TI_ADS7950_MAN_CMD_SETTINGS(st) \
 | |
| 	(TI_ADS7950_MAN_CMD(TI_ADS7950_CR_WRITE | st->cmd_settings_bitmask))
 | |
| /* GPIO mode configuration */
 | |
| #define TI_ADS7950_GPIO_CMD_SETTINGS(st) \
 | |
| 	(TI_ADS7950_GPIO_CMD(st->gpio_cmd_settings_bitmask))
 | |
| 
 | |
| struct ti_ads7950_state {
 | |
| 	struct spi_device	*spi;
 | |
| 	struct spi_transfer	ring_xfer;
 | |
| 	struct spi_transfer	scan_single_xfer[3];
 | |
| 	struct spi_message	ring_msg;
 | |
| 	struct spi_message	scan_single_msg;
 | |
| 
 | |
| 	/* Lock to protect the spi xfer buffers */
 | |
| 	struct mutex		slock;
 | |
| 	struct gpio_chip	chip;
 | |
| 
 | |
| 	struct regulator	*reg;
 | |
| 	unsigned int		vref_mv;
 | |
| 
 | |
| 	/*
 | |
| 	 * Bitmask of lower 7 bits used for configuration
 | |
| 	 * These bits only can be written when TI_ADS7950_CR_WRITE
 | |
| 	 * is set, otherwise it retains its original state.
 | |
| 	 * [0-3] GPIO signal
 | |
| 	 * [4]   Set following frame to return GPIO signal values
 | |
| 	 * [5]   Powers down device
 | |
| 	 * [6]   Sets Vref range1(2.5v) or range2(5v)
 | |
| 	 *
 | |
| 	 * Bits present on Manual/Auto1/Auto2 commands
 | |
| 	 */
 | |
| 	unsigned int		cmd_settings_bitmask;
 | |
| 
 | |
| 	/*
 | |
| 	 * Bitmask of GPIO command
 | |
| 	 * [0-3] GPIO direction
 | |
| 	 * [4-6] Different GPIO alarm mode configurations
 | |
| 	 * [7]   GPIO 2 as device range input
 | |
| 	 * [8]   GPIO 3 as device power down input
 | |
| 	 * [9]   Reset all registers
 | |
| 	 * [10-11] N/A
 | |
| 	 */
 | |
| 	unsigned int		gpio_cmd_settings_bitmask;
 | |
| 
 | |
| 	/*
 | |
| 	 * DMA (thus cache coherency maintenance) may require the
 | |
| 	 * transfer buffers to live in their own cache lines.
 | |
| 	 */
 | |
| 	u16 rx_buf[TI_ADS7950_MAX_CHAN + 2 + TI_ADS7950_TIMESTAMP_SIZE]
 | |
| 		__aligned(IIO_DMA_MINALIGN);
 | |
| 	u16 tx_buf[TI_ADS7950_MAX_CHAN + 2];
 | |
| 	u16 single_tx;
 | |
| 	u16 single_rx;
 | |
| 
 | |
| };
 | |
| 
 | |
| struct ti_ads7950_chip_info {
 | |
| 	const struct iio_chan_spec *channels;
 | |
| 	unsigned int num_channels;
 | |
| };
 | |
| 
 | |
| enum ti_ads7950_id {
 | |
| 	TI_ADS7950,
 | |
| 	TI_ADS7951,
 | |
| 	TI_ADS7952,
 | |
| 	TI_ADS7953,
 | |
| 	TI_ADS7954,
 | |
| 	TI_ADS7955,
 | |
| 	TI_ADS7956,
 | |
| 	TI_ADS7957,
 | |
| 	TI_ADS7958,
 | |
| 	TI_ADS7959,
 | |
| 	TI_ADS7960,
 | |
| 	TI_ADS7961,
 | |
| };
 | |
| 
 | |
| #define TI_ADS7950_V_CHAN(index, bits)				\
 | |
| {								\
 | |
| 	.type = IIO_VOLTAGE,					\
 | |
| 	.indexed = 1,						\
 | |
| 	.channel = index,					\
 | |
| 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
 | |
| 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
 | |
| 	.address = index,					\
 | |
| 	.datasheet_name = "CH##index",				\
 | |
| 	.scan_index = index,					\
 | |
| 	.scan_type = {						\
 | |
| 		.sign = 'u',					\
 | |
| 		.realbits = bits,				\
 | |
| 		.storagebits = 16,				\
 | |
| 		.shift = 12 - (bits),				\
 | |
| 		.endianness = IIO_CPU,				\
 | |
| 	},							\
 | |
| }
 | |
| 
 | |
| #define DECLARE_TI_ADS7950_4_CHANNELS(name, bits) \
 | |
| const struct iio_chan_spec name ## _channels[] = { \
 | |
| 	TI_ADS7950_V_CHAN(0, bits), \
 | |
| 	TI_ADS7950_V_CHAN(1, bits), \
 | |
| 	TI_ADS7950_V_CHAN(2, bits), \
 | |
| 	TI_ADS7950_V_CHAN(3, bits), \
 | |
| 	IIO_CHAN_SOFT_TIMESTAMP(4), \
 | |
| }
 | |
| 
 | |
| #define DECLARE_TI_ADS7950_8_CHANNELS(name, bits) \
 | |
| const struct iio_chan_spec name ## _channels[] = { \
 | |
| 	TI_ADS7950_V_CHAN(0, bits), \
 | |
| 	TI_ADS7950_V_CHAN(1, bits), \
 | |
| 	TI_ADS7950_V_CHAN(2, bits), \
 | |
| 	TI_ADS7950_V_CHAN(3, bits), \
 | |
| 	TI_ADS7950_V_CHAN(4, bits), \
 | |
| 	TI_ADS7950_V_CHAN(5, bits), \
 | |
| 	TI_ADS7950_V_CHAN(6, bits), \
 | |
| 	TI_ADS7950_V_CHAN(7, bits), \
 | |
| 	IIO_CHAN_SOFT_TIMESTAMP(8), \
 | |
| }
 | |
| 
 | |
| #define DECLARE_TI_ADS7950_12_CHANNELS(name, bits) \
 | |
| const struct iio_chan_spec name ## _channels[] = { \
 | |
| 	TI_ADS7950_V_CHAN(0, bits), \
 | |
| 	TI_ADS7950_V_CHAN(1, bits), \
 | |
| 	TI_ADS7950_V_CHAN(2, bits), \
 | |
| 	TI_ADS7950_V_CHAN(3, bits), \
 | |
| 	TI_ADS7950_V_CHAN(4, bits), \
 | |
| 	TI_ADS7950_V_CHAN(5, bits), \
 | |
| 	TI_ADS7950_V_CHAN(6, bits), \
 | |
| 	TI_ADS7950_V_CHAN(7, bits), \
 | |
| 	TI_ADS7950_V_CHAN(8, bits), \
 | |
| 	TI_ADS7950_V_CHAN(9, bits), \
 | |
| 	TI_ADS7950_V_CHAN(10, bits), \
 | |
| 	TI_ADS7950_V_CHAN(11, bits), \
 | |
| 	IIO_CHAN_SOFT_TIMESTAMP(12), \
 | |
| }
 | |
| 
 | |
| #define DECLARE_TI_ADS7950_16_CHANNELS(name, bits) \
 | |
| const struct iio_chan_spec name ## _channels[] = { \
 | |
| 	TI_ADS7950_V_CHAN(0, bits), \
 | |
| 	TI_ADS7950_V_CHAN(1, bits), \
 | |
| 	TI_ADS7950_V_CHAN(2, bits), \
 | |
| 	TI_ADS7950_V_CHAN(3, bits), \
 | |
| 	TI_ADS7950_V_CHAN(4, bits), \
 | |
| 	TI_ADS7950_V_CHAN(5, bits), \
 | |
| 	TI_ADS7950_V_CHAN(6, bits), \
 | |
| 	TI_ADS7950_V_CHAN(7, bits), \
 | |
| 	TI_ADS7950_V_CHAN(8, bits), \
 | |
| 	TI_ADS7950_V_CHAN(9, bits), \
 | |
| 	TI_ADS7950_V_CHAN(10, bits), \
 | |
| 	TI_ADS7950_V_CHAN(11, bits), \
 | |
| 	TI_ADS7950_V_CHAN(12, bits), \
 | |
| 	TI_ADS7950_V_CHAN(13, bits), \
 | |
| 	TI_ADS7950_V_CHAN(14, bits), \
 | |
| 	TI_ADS7950_V_CHAN(15, bits), \
 | |
| 	IIO_CHAN_SOFT_TIMESTAMP(16), \
 | |
| }
 | |
| 
 | |
| static DECLARE_TI_ADS7950_4_CHANNELS(ti_ads7950, 12);
 | |
| static DECLARE_TI_ADS7950_8_CHANNELS(ti_ads7951, 12);
 | |
| static DECLARE_TI_ADS7950_12_CHANNELS(ti_ads7952, 12);
 | |
| static DECLARE_TI_ADS7950_16_CHANNELS(ti_ads7953, 12);
 | |
| static DECLARE_TI_ADS7950_4_CHANNELS(ti_ads7954, 10);
 | |
| static DECLARE_TI_ADS7950_8_CHANNELS(ti_ads7955, 10);
 | |
| static DECLARE_TI_ADS7950_12_CHANNELS(ti_ads7956, 10);
 | |
| static DECLARE_TI_ADS7950_16_CHANNELS(ti_ads7957, 10);
 | |
| static DECLARE_TI_ADS7950_4_CHANNELS(ti_ads7958, 8);
 | |
| static DECLARE_TI_ADS7950_8_CHANNELS(ti_ads7959, 8);
 | |
| static DECLARE_TI_ADS7950_12_CHANNELS(ti_ads7960, 8);
 | |
| static DECLARE_TI_ADS7950_16_CHANNELS(ti_ads7961, 8);
 | |
| 
 | |
| static const struct ti_ads7950_chip_info ti_ads7950_chip_info[] = {
 | |
| 	[TI_ADS7950] = {
 | |
| 		.channels	= ti_ads7950_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7950_channels),
 | |
| 	},
 | |
| 	[TI_ADS7951] = {
 | |
| 		.channels	= ti_ads7951_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7951_channels),
 | |
| 	},
 | |
| 	[TI_ADS7952] = {
 | |
| 		.channels	= ti_ads7952_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7952_channels),
 | |
| 	},
 | |
| 	[TI_ADS7953] = {
 | |
| 		.channels	= ti_ads7953_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7953_channels),
 | |
| 	},
 | |
| 	[TI_ADS7954] = {
 | |
| 		.channels	= ti_ads7954_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7954_channels),
 | |
| 	},
 | |
| 	[TI_ADS7955] = {
 | |
| 		.channels	= ti_ads7955_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7955_channels),
 | |
| 	},
 | |
| 	[TI_ADS7956] = {
 | |
| 		.channels	= ti_ads7956_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7956_channels),
 | |
| 	},
 | |
| 	[TI_ADS7957] = {
 | |
| 		.channels	= ti_ads7957_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7957_channels),
 | |
| 	},
 | |
| 	[TI_ADS7958] = {
 | |
| 		.channels	= ti_ads7958_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7958_channels),
 | |
| 	},
 | |
| 	[TI_ADS7959] = {
 | |
| 		.channels	= ti_ads7959_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7959_channels),
 | |
| 	},
 | |
| 	[TI_ADS7960] = {
 | |
| 		.channels	= ti_ads7960_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7960_channels),
 | |
| 	},
 | |
| 	[TI_ADS7961] = {
 | |
| 		.channels	= ti_ads7961_channels,
 | |
| 		.num_channels	= ARRAY_SIZE(ti_ads7961_channels),
 | |
| 	},
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * ti_ads7950_update_scan_mode() setup the spi transfer buffer for the new
 | |
|  * scan mask
 | |
|  */
 | |
| static int ti_ads7950_update_scan_mode(struct iio_dev *indio_dev,
 | |
| 				       const unsigned long *active_scan_mask)
 | |
| {
 | |
| 	struct ti_ads7950_state *st = iio_priv(indio_dev);
 | |
| 	int i, cmd, len;
 | |
| 
 | |
| 	len = 0;
 | |
| 	for_each_set_bit(i, active_scan_mask, indio_dev->num_channels) {
 | |
| 		cmd = TI_ADS7950_MAN_CMD(TI_ADS7950_CR_CHAN(i));
 | |
| 		st->tx_buf[len++] = cmd;
 | |
| 	}
 | |
| 
 | |
| 	/* Data for the 1st channel is not returned until the 3rd transfer */
 | |
| 	st->tx_buf[len++] = 0;
 | |
| 	st->tx_buf[len++] = 0;
 | |
| 
 | |
| 	st->ring_xfer.len = len * 2;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static irqreturn_t ti_ads7950_trigger_handler(int irq, void *p)
 | |
| {
 | |
| 	struct iio_poll_func *pf = p;
 | |
| 	struct iio_dev *indio_dev = pf->indio_dev;
 | |
| 	struct ti_ads7950_state *st = iio_priv(indio_dev);
 | |
| 	int ret;
 | |
| 
 | |
| 	mutex_lock(&st->slock);
 | |
| 	ret = spi_sync(st->spi, &st->ring_msg);
 | |
| 	if (ret < 0)
 | |
| 		goto out;
 | |
| 
 | |
| 	iio_push_to_buffers_with_timestamp(indio_dev, &st->rx_buf[2],
 | |
| 					   iio_get_time_ns(indio_dev));
 | |
| 
 | |
| out:
 | |
| 	mutex_unlock(&st->slock);
 | |
| 	iio_trigger_notify_done(indio_dev->trig);
 | |
| 
 | |
| 	return IRQ_HANDLED;
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
 | |
| {
 | |
| 	struct ti_ads7950_state *st = iio_priv(indio_dev);
 | |
| 	int ret, cmd;
 | |
| 
 | |
| 	mutex_lock(&st->slock);
 | |
| 	cmd = TI_ADS7950_MAN_CMD(TI_ADS7950_CR_CHAN(ch));
 | |
| 	st->single_tx = cmd;
 | |
| 
 | |
| 	ret = spi_sync(st->spi, &st->scan_single_msg);
 | |
| 	if (ret)
 | |
| 		goto out;
 | |
| 
 | |
| 	ret = st->single_rx;
 | |
| 
 | |
| out:
 | |
| 	mutex_unlock(&st->slock);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_get_range(struct ti_ads7950_state *st)
 | |
| {
 | |
| 	int vref;
 | |
| 
 | |
| 	if (st->vref_mv) {
 | |
| 		vref = st->vref_mv;
 | |
| 	} else {
 | |
| 		vref = regulator_get_voltage(st->reg);
 | |
| 		if (vref < 0)
 | |
| 			return vref;
 | |
| 
 | |
| 		vref /= 1000;
 | |
| 	}
 | |
| 
 | |
| 	if (st->cmd_settings_bitmask & TI_ADS7950_CR_RANGE_5V)
 | |
| 		vref *= 2;
 | |
| 
 | |
| 	return vref;
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_read_raw(struct iio_dev *indio_dev,
 | |
| 			       struct iio_chan_spec const *chan,
 | |
| 			       int *val, int *val2, long m)
 | |
| {
 | |
| 	struct ti_ads7950_state *st = iio_priv(indio_dev);
 | |
| 	int ret;
 | |
| 
 | |
| 	switch (m) {
 | |
| 	case IIO_CHAN_INFO_RAW:
 | |
| 		ret = ti_ads7950_scan_direct(indio_dev, chan->address);
 | |
| 		if (ret < 0)
 | |
| 			return ret;
 | |
| 
 | |
| 		if (chan->address != TI_ADS7950_EXTRACT(ret, 12, 4))
 | |
| 			return -EIO;
 | |
| 
 | |
| 		*val = TI_ADS7950_EXTRACT(ret, chan->scan_type.shift,
 | |
| 					  chan->scan_type.realbits);
 | |
| 
 | |
| 		return IIO_VAL_INT;
 | |
| 	case IIO_CHAN_INFO_SCALE:
 | |
| 		ret = ti_ads7950_get_range(st);
 | |
| 		if (ret < 0)
 | |
| 			return ret;
 | |
| 
 | |
| 		*val = ret;
 | |
| 		*val2 = (1 << chan->scan_type.realbits) - 1;
 | |
| 
 | |
| 		return IIO_VAL_FRACTIONAL;
 | |
| 	}
 | |
| 
 | |
| 	return -EINVAL;
 | |
| }
 | |
| 
 | |
| static const struct iio_info ti_ads7950_info = {
 | |
| 	.read_raw		= &ti_ads7950_read_raw,
 | |
| 	.update_scan_mode	= ti_ads7950_update_scan_mode,
 | |
| };
 | |
| 
 | |
| static void ti_ads7950_set(struct gpio_chip *chip, unsigned int offset,
 | |
| 			   int value)
 | |
| {
 | |
| 	struct ti_ads7950_state *st = gpiochip_get_data(chip);
 | |
| 
 | |
| 	mutex_lock(&st->slock);
 | |
| 
 | |
| 	if (value)
 | |
| 		st->cmd_settings_bitmask |= BIT(offset);
 | |
| 	else
 | |
| 		st->cmd_settings_bitmask &= ~BIT(offset);
 | |
| 
 | |
| 	st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
 | |
| 	spi_sync(st->spi, &st->scan_single_msg);
 | |
| 
 | |
| 	mutex_unlock(&st->slock);
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_get(struct gpio_chip *chip, unsigned int offset)
 | |
| {
 | |
| 	struct ti_ads7950_state *st = gpiochip_get_data(chip);
 | |
| 	int ret;
 | |
| 
 | |
| 	mutex_lock(&st->slock);
 | |
| 
 | |
| 	/* If set as output, return the output */
 | |
| 	if (st->gpio_cmd_settings_bitmask & BIT(offset)) {
 | |
| 		ret = st->cmd_settings_bitmask & BIT(offset);
 | |
| 		goto out;
 | |
| 	}
 | |
| 
 | |
| 	/* GPIO data bit sets SDO bits 12-15 to GPIO input */
 | |
| 	st->cmd_settings_bitmask |= TI_ADS7950_CR_GPIO_DATA;
 | |
| 	st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
 | |
| 	ret = spi_sync(st->spi, &st->scan_single_msg);
 | |
| 	if (ret)
 | |
| 		goto out;
 | |
| 
 | |
| 	ret = ((st->single_rx >> 12) & BIT(offset)) ? 1 : 0;
 | |
| 
 | |
| 	/* Revert back to original settings */
 | |
| 	st->cmd_settings_bitmask &= ~TI_ADS7950_CR_GPIO_DATA;
 | |
| 	st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
 | |
| 	ret = spi_sync(st->spi, &st->scan_single_msg);
 | |
| 	if (ret)
 | |
| 		goto out;
 | |
| 
 | |
| out:
 | |
| 	mutex_unlock(&st->slock);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_get_direction(struct gpio_chip *chip,
 | |
| 				    unsigned int offset)
 | |
| {
 | |
| 	struct ti_ads7950_state *st = gpiochip_get_data(chip);
 | |
| 
 | |
| 	/* Bitmask is inverted from GPIO framework 0=input/1=output */
 | |
| 	return !(st->gpio_cmd_settings_bitmask & BIT(offset));
 | |
| }
 | |
| 
 | |
| static int _ti_ads7950_set_direction(struct gpio_chip *chip, int offset,
 | |
| 				     int input)
 | |
| {
 | |
| 	struct ti_ads7950_state *st = gpiochip_get_data(chip);
 | |
| 	int ret = 0;
 | |
| 
 | |
| 	mutex_lock(&st->slock);
 | |
| 
 | |
| 	/* Only change direction if needed */
 | |
| 	if (input && (st->gpio_cmd_settings_bitmask & BIT(offset)))
 | |
| 		st->gpio_cmd_settings_bitmask &= ~BIT(offset);
 | |
| 	else if (!input && !(st->gpio_cmd_settings_bitmask & BIT(offset)))
 | |
| 		st->gpio_cmd_settings_bitmask |= BIT(offset);
 | |
| 	else
 | |
| 		goto out;
 | |
| 
 | |
| 	st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st);
 | |
| 	ret = spi_sync(st->spi, &st->scan_single_msg);
 | |
| 
 | |
| out:
 | |
| 	mutex_unlock(&st->slock);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_direction_input(struct gpio_chip *chip,
 | |
| 				      unsigned int offset)
 | |
| {
 | |
| 	return _ti_ads7950_set_direction(chip, offset, 1);
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_direction_output(struct gpio_chip *chip,
 | |
| 				       unsigned int offset, int value)
 | |
| {
 | |
| 	ti_ads7950_set(chip, offset, value);
 | |
| 
 | |
| 	return _ti_ads7950_set_direction(chip, offset, 0);
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_init_hw(struct ti_ads7950_state *st)
 | |
| {
 | |
| 	int ret = 0;
 | |
| 
 | |
| 	mutex_lock(&st->slock);
 | |
| 
 | |
| 	/* Settings for Manual/Auto1/Auto2 commands */
 | |
| 	/* Default to 5v ref */
 | |
| 	st->cmd_settings_bitmask = TI_ADS7950_CR_RANGE_5V;
 | |
| 	st->single_tx = TI_ADS7950_MAN_CMD_SETTINGS(st);
 | |
| 	ret = spi_sync(st->spi, &st->scan_single_msg);
 | |
| 	if (ret)
 | |
| 		goto out;
 | |
| 
 | |
| 	/* Settings for GPIO command */
 | |
| 	st->gpio_cmd_settings_bitmask = 0x0;
 | |
| 	st->single_tx = TI_ADS7950_GPIO_CMD_SETTINGS(st);
 | |
| 	ret = spi_sync(st->spi, &st->scan_single_msg);
 | |
| 
 | |
| out:
 | |
| 	mutex_unlock(&st->slock);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static int ti_ads7950_probe(struct spi_device *spi)
 | |
| {
 | |
| 	struct ti_ads7950_state *st;
 | |
| 	struct iio_dev *indio_dev;
 | |
| 	const struct ti_ads7950_chip_info *info;
 | |
| 	int ret;
 | |
| 
 | |
| 	spi->bits_per_word = 16;
 | |
| 	spi->mode |= SPI_CS_WORD;
 | |
| 	ret = spi_setup(spi);
 | |
| 	if (ret < 0) {
 | |
| 		dev_err(&spi->dev, "Error in spi setup\n");
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
 | |
| 	if (!indio_dev)
 | |
| 		return -ENOMEM;
 | |
| 
 | |
| 	st = iio_priv(indio_dev);
 | |
| 
 | |
| 	spi_set_drvdata(spi, indio_dev);
 | |
| 
 | |
| 	st->spi = spi;
 | |
| 
 | |
| 	info = &ti_ads7950_chip_info[spi_get_device_id(spi)->driver_data];
 | |
| 
 | |
| 	indio_dev->name = spi_get_device_id(spi)->name;
 | |
| 	indio_dev->modes = INDIO_DIRECT_MODE;
 | |
| 	indio_dev->channels = info->channels;
 | |
| 	indio_dev->num_channels = info->num_channels;
 | |
| 	indio_dev->info = &ti_ads7950_info;
 | |
| 
 | |
| 	/* build spi ring message */
 | |
| 	spi_message_init(&st->ring_msg);
 | |
| 
 | |
| 	st->ring_xfer.tx_buf = &st->tx_buf[0];
 | |
| 	st->ring_xfer.rx_buf = &st->rx_buf[0];
 | |
| 	/* len will be set later */
 | |
| 
 | |
| 	spi_message_add_tail(&st->ring_xfer, &st->ring_msg);
 | |
| 
 | |
| 	/*
 | |
| 	 * Setup default message. The sample is read at the end of the first
 | |
| 	 * transfer, then it takes one full cycle to convert the sample and one
 | |
| 	 * more cycle to send the value. The conversion process is driven by
 | |
| 	 * the SPI clock, which is why we have 3 transfers. The middle one is
 | |
| 	 * just dummy data sent while the chip is converting the sample that
 | |
| 	 * was read at the end of the first transfer.
 | |
| 	 */
 | |
| 
 | |
| 	st->scan_single_xfer[0].tx_buf = &st->single_tx;
 | |
| 	st->scan_single_xfer[0].len = 2;
 | |
| 	st->scan_single_xfer[0].cs_change = 1;
 | |
| 	st->scan_single_xfer[1].tx_buf = &st->single_tx;
 | |
| 	st->scan_single_xfer[1].len = 2;
 | |
| 	st->scan_single_xfer[1].cs_change = 1;
 | |
| 	st->scan_single_xfer[2].rx_buf = &st->single_rx;
 | |
| 	st->scan_single_xfer[2].len = 2;
 | |
| 
 | |
| 	spi_message_init_with_transfers(&st->scan_single_msg,
 | |
| 					st->scan_single_xfer, 3);
 | |
| 
 | |
| 	/* Use hard coded value for reference voltage in ACPI case */
 | |
| 	if (ACPI_COMPANION(&spi->dev))
 | |
| 		st->vref_mv = TI_ADS7950_VA_MV_ACPI_DEFAULT;
 | |
| 
 | |
| 	mutex_init(&st->slock);
 | |
| 
 | |
| 	st->reg = devm_regulator_get(&spi->dev, "vref");
 | |
| 	if (IS_ERR(st->reg)) {
 | |
| 		ret = dev_err_probe(&spi->dev, PTR_ERR(st->reg),
 | |
| 				     "Failed to get regulator \"vref\"\n");
 | |
| 		goto error_destroy_mutex;
 | |
| 	}
 | |
| 
 | |
| 	ret = regulator_enable(st->reg);
 | |
| 	if (ret) {
 | |
| 		dev_err(&spi->dev, "Failed to enable regulator \"vref\"\n");
 | |
| 		goto error_destroy_mutex;
 | |
| 	}
 | |
| 
 | |
| 	ret = iio_triggered_buffer_setup(indio_dev, NULL,
 | |
| 					 &ti_ads7950_trigger_handler, NULL);
 | |
| 	if (ret) {
 | |
| 		dev_err(&spi->dev, "Failed to setup triggered buffer\n");
 | |
| 		goto error_disable_reg;
 | |
| 	}
 | |
| 
 | |
| 	ret = ti_ads7950_init_hw(st);
 | |
| 	if (ret) {
 | |
| 		dev_err(&spi->dev, "Failed to init adc chip\n");
 | |
| 		goto error_cleanup_ring;
 | |
| 	}
 | |
| 
 | |
| 	ret = iio_device_register(indio_dev);
 | |
| 	if (ret) {
 | |
| 		dev_err(&spi->dev, "Failed to register iio device\n");
 | |
| 		goto error_cleanup_ring;
 | |
| 	}
 | |
| 
 | |
| 	/* Add GPIO chip */
 | |
| 	st->chip.label = dev_name(&st->spi->dev);
 | |
| 	st->chip.parent = &st->spi->dev;
 | |
| 	st->chip.owner = THIS_MODULE;
 | |
| 	st->chip.can_sleep = true;
 | |
| 	st->chip.base = -1;
 | |
| 	st->chip.ngpio = TI_ADS7950_NUM_GPIOS;
 | |
| 	st->chip.get_direction = ti_ads7950_get_direction;
 | |
| 	st->chip.direction_input = ti_ads7950_direction_input;
 | |
| 	st->chip.direction_output = ti_ads7950_direction_output;
 | |
| 	st->chip.get = ti_ads7950_get;
 | |
| 	st->chip.set = ti_ads7950_set;
 | |
| 
 | |
| 	ret = gpiochip_add_data(&st->chip, st);
 | |
| 	if (ret) {
 | |
| 		dev_err(&spi->dev, "Failed to init GPIOs\n");
 | |
| 		goto error_iio_device;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| 
 | |
| error_iio_device:
 | |
| 	iio_device_unregister(indio_dev);
 | |
| error_cleanup_ring:
 | |
| 	iio_triggered_buffer_cleanup(indio_dev);
 | |
| error_disable_reg:
 | |
| 	regulator_disable(st->reg);
 | |
| error_destroy_mutex:
 | |
| 	mutex_destroy(&st->slock);
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static void ti_ads7950_remove(struct spi_device *spi)
 | |
| {
 | |
| 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
 | |
| 	struct ti_ads7950_state *st = iio_priv(indio_dev);
 | |
| 
 | |
| 	gpiochip_remove(&st->chip);
 | |
| 	iio_device_unregister(indio_dev);
 | |
| 	iio_triggered_buffer_cleanup(indio_dev);
 | |
| 	regulator_disable(st->reg);
 | |
| 	mutex_destroy(&st->slock);
 | |
| }
 | |
| 
 | |
| static const struct spi_device_id ti_ads7950_id[] = {
 | |
| 	{ "ads7950", TI_ADS7950 },
 | |
| 	{ "ads7951", TI_ADS7951 },
 | |
| 	{ "ads7952", TI_ADS7952 },
 | |
| 	{ "ads7953", TI_ADS7953 },
 | |
| 	{ "ads7954", TI_ADS7954 },
 | |
| 	{ "ads7955", TI_ADS7955 },
 | |
| 	{ "ads7956", TI_ADS7956 },
 | |
| 	{ "ads7957", TI_ADS7957 },
 | |
| 	{ "ads7958", TI_ADS7958 },
 | |
| 	{ "ads7959", TI_ADS7959 },
 | |
| 	{ "ads7960", TI_ADS7960 },
 | |
| 	{ "ads7961", TI_ADS7961 },
 | |
| 	{ }
 | |
| };
 | |
| MODULE_DEVICE_TABLE(spi, ti_ads7950_id);
 | |
| 
 | |
| static const struct of_device_id ads7950_of_table[] = {
 | |
| 	{ .compatible = "ti,ads7950", .data = &ti_ads7950_chip_info[TI_ADS7950] },
 | |
| 	{ .compatible = "ti,ads7951", .data = &ti_ads7950_chip_info[TI_ADS7951] },
 | |
| 	{ .compatible = "ti,ads7952", .data = &ti_ads7950_chip_info[TI_ADS7952] },
 | |
| 	{ .compatible = "ti,ads7953", .data = &ti_ads7950_chip_info[TI_ADS7953] },
 | |
| 	{ .compatible = "ti,ads7954", .data = &ti_ads7950_chip_info[TI_ADS7954] },
 | |
| 	{ .compatible = "ti,ads7955", .data = &ti_ads7950_chip_info[TI_ADS7955] },
 | |
| 	{ .compatible = "ti,ads7956", .data = &ti_ads7950_chip_info[TI_ADS7956] },
 | |
| 	{ .compatible = "ti,ads7957", .data = &ti_ads7950_chip_info[TI_ADS7957] },
 | |
| 	{ .compatible = "ti,ads7958", .data = &ti_ads7950_chip_info[TI_ADS7958] },
 | |
| 	{ .compatible = "ti,ads7959", .data = &ti_ads7950_chip_info[TI_ADS7959] },
 | |
| 	{ .compatible = "ti,ads7960", .data = &ti_ads7950_chip_info[TI_ADS7960] },
 | |
| 	{ .compatible = "ti,ads7961", .data = &ti_ads7950_chip_info[TI_ADS7961] },
 | |
| 	{ },
 | |
| };
 | |
| MODULE_DEVICE_TABLE(of, ads7950_of_table);
 | |
| 
 | |
| static struct spi_driver ti_ads7950_driver = {
 | |
| 	.driver = {
 | |
| 		.name	= "ads7950",
 | |
| 		.of_match_table = ads7950_of_table,
 | |
| 	},
 | |
| 	.probe		= ti_ads7950_probe,
 | |
| 	.remove		= ti_ads7950_remove,
 | |
| 	.id_table	= ti_ads7950_id,
 | |
| };
 | |
| module_spi_driver(ti_ads7950_driver);
 | |
| 
 | |
| MODULE_AUTHOR("David Lechner <david@lechnology.com>");
 | |
| MODULE_DESCRIPTION("TI TI_ADS7950 ADC");
 | |
| MODULE_LICENSE("GPL v2");
 |