| // 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 - http://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) requires the | 
 | 	 * transfer buffers to live in their own cache lines. | 
 | 	 */ | 
 | 	u16 rx_buf[TI_ADS7950_MAX_CHAN + 2 + TI_ADS7950_TIMESTAMP_SIZE] | 
 | 							____cacheline_aligned; | 
 | 	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->dev.parent = &spi->dev; | 
 | 	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 */ | 
 | 	st->ring_xfer.cs_change = true; | 
 |  | 
 | 	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)) { | 
 | 		dev_err(&spi->dev, "Failed to get regulator \"vref\"\n"); | 
 | 		ret = PTR_ERR(st->reg); | 
 | 		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.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 int 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); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | 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"); |