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v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Driver for Microchip MCP3911, Two-channel Analog Front End
  4 *
  5 * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com>
  6 * Copyright (C) 2018 Kent Gustavsson <kent@minoris.se>
  7 */
  8#include <linux/clk.h>
  9#include <linux/delay.h>
 10#include <linux/err.h>
 11#include <linux/iio/iio.h>
 12#include <linux/module.h>
 13#include <linux/regulator/consumer.h>
 14#include <linux/spi/spi.h>
 15
 16#define MCP3911_REG_CHANNEL0		0x00
 17#define MCP3911_REG_CHANNEL1		0x03
 18#define MCP3911_REG_MOD			0x06
 19#define MCP3911_REG_PHASE		0x07
 20#define MCP3911_REG_GAIN		0x09
 21
 22#define MCP3911_REG_STATUSCOM		0x0a
 23#define MCP3911_STATUSCOM_CH1_24WIDTH	BIT(4)
 24#define MCP3911_STATUSCOM_CH0_24WIDTH	BIT(3)
 25#define MCP3911_STATUSCOM_EN_OFFCAL	BIT(2)
 26#define MCP3911_STATUSCOM_EN_GAINCAL	BIT(1)
 27
 28#define MCP3911_REG_CONFIG		0x0c
 29#define MCP3911_CONFIG_CLKEXT		BIT(1)
 30#define MCP3911_CONFIG_VREFEXT		BIT(2)
 31
 32#define MCP3911_REG_OFFCAL_CH0		0x0e
 33#define MCP3911_REG_GAINCAL_CH0		0x11
 34#define MCP3911_REG_OFFCAL_CH1		0x14
 35#define MCP3911_REG_GAINCAL_CH1		0x17
 36#define MCP3911_REG_VREFCAL		0x1a
 37
 38#define MCP3911_CHANNEL(x)		(MCP3911_REG_CHANNEL0 + x * 3)
 39#define MCP3911_OFFCAL(x)		(MCP3911_REG_OFFCAL_CH0 + x * 6)
 40
 41/* Internal voltage reference in uV */
 42#define MCP3911_INT_VREF_UV		1200000
 43
 44#define MCP3911_REG_READ(reg, id)	((((reg) << 1) | ((id) << 5) | (1 << 0)) & 0xff)
 45#define MCP3911_REG_WRITE(reg, id)	((((reg) << 1) | ((id) << 5) | (0 << 0)) & 0xff)
 46
 47#define MCP3911_NUM_CHANNELS		2
 48
 49struct mcp3911 {
 50	struct spi_device *spi;
 51	struct mutex lock;
 52	struct regulator *vref;
 53	struct clk *clki;
 54	u32 dev_addr;
 55};
 56
 57static int mcp3911_read(struct mcp3911 *adc, u8 reg, u32 *val, u8 len)
 58{
 59	int ret;
 60
 61	reg = MCP3911_REG_READ(reg, adc->dev_addr);
 62	ret = spi_write_then_read(adc->spi, &reg, 1, val, len);
 63	if (ret < 0)
 64		return ret;
 65
 66	be32_to_cpus(val);
 67	*val >>= ((4 - len) * 8);
 68	dev_dbg(&adc->spi->dev, "reading 0x%x from register 0x%x\n", *val,
 69		reg >> 1);
 70	return ret;
 71}
 72
 73static int mcp3911_write(struct mcp3911 *adc, u8 reg, u32 val, u8 len)
 74{
 75	dev_dbg(&adc->spi->dev, "writing 0x%x to register 0x%x\n", val, reg);
 76
 77	val <<= (3 - len) * 8;
 78	cpu_to_be32s(&val);
 79	val |= MCP3911_REG_WRITE(reg, adc->dev_addr);
 80
 81	return spi_write(adc->spi, &val, len + 1);
 82}
 83
 84static int mcp3911_update(struct mcp3911 *adc, u8 reg, u32 mask,
 85		u32 val, u8 len)
 86{
 87	u32 tmp;
 88	int ret;
 89
 90	ret = mcp3911_read(adc, reg, &tmp, len);
 91	if (ret)
 92		return ret;
 93
 94	val &= mask;
 95	val |= tmp & ~mask;
 96	return mcp3911_write(adc, reg, val, len);
 97}
 98
 99static int mcp3911_read_raw(struct iio_dev *indio_dev,
100			    struct iio_chan_spec const *channel, int *val,
101			    int *val2, long mask)
102{
103	struct mcp3911 *adc = iio_priv(indio_dev);
104	int ret = -EINVAL;
105
106	mutex_lock(&adc->lock);
107	switch (mask) {
108	case IIO_CHAN_INFO_RAW:
109		ret = mcp3911_read(adc,
110				   MCP3911_CHANNEL(channel->channel), val, 3);
111		if (ret)
112			goto out;
113
114		ret = IIO_VAL_INT;
115		break;
116
117	case IIO_CHAN_INFO_OFFSET:
118		ret = mcp3911_read(adc,
119				   MCP3911_OFFCAL(channel->channel), val, 3);
120		if (ret)
121			goto out;
122
123		ret = IIO_VAL_INT;
124		break;
125
126	case IIO_CHAN_INFO_SCALE:
127		if (adc->vref) {
128			ret = regulator_get_voltage(adc->vref);
129			if (ret < 0) {
130				dev_err(indio_dev->dev.parent,
131					"failed to get vref voltage: %d\n",
132				       ret);
133				goto out;
134			}
135
136			*val = ret / 1000;
137		} else {
138			*val = MCP3911_INT_VREF_UV;
139		}
140
141		*val2 = 24;
142		ret = IIO_VAL_FRACTIONAL_LOG2;
143		break;
144	}
145
146out:
147	mutex_unlock(&adc->lock);
148	return ret;
149}
150
151static int mcp3911_write_raw(struct iio_dev *indio_dev,
152			    struct iio_chan_spec const *channel, int val,
153			    int val2, long mask)
154{
155	struct mcp3911 *adc = iio_priv(indio_dev);
156	int ret = -EINVAL;
157
158	mutex_lock(&adc->lock);
159	switch (mask) {
160	case IIO_CHAN_INFO_OFFSET:
161		if (val2 != 0) {
162			ret = -EINVAL;
163			goto out;
164		}
165
166		/* Write offset */
167		ret = mcp3911_write(adc, MCP3911_OFFCAL(channel->channel), val,
168				    3);
169		if (ret)
170			goto out;
171
172		/* Enable offset*/
173		ret = mcp3911_update(adc, MCP3911_REG_STATUSCOM,
174				MCP3911_STATUSCOM_EN_OFFCAL,
175				MCP3911_STATUSCOM_EN_OFFCAL, 2);
176		break;
177	}
178
179out:
180	mutex_unlock(&adc->lock);
181	return ret;
182}
183
184#define MCP3911_CHAN(idx) {					\
185		.type = IIO_VOLTAGE,				\
186		.indexed = 1,					\
187		.channel = idx,					\
188		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
189			BIT(IIO_CHAN_INFO_OFFSET) |		\
190			BIT(IIO_CHAN_INFO_SCALE),		\
191}
192
193static const struct iio_chan_spec mcp3911_channels[] = {
194	MCP3911_CHAN(0),
195	MCP3911_CHAN(1),
196};
197
198static const struct iio_info mcp3911_info = {
199	.read_raw = mcp3911_read_raw,
200	.write_raw = mcp3911_write_raw,
201};
202
203static int mcp3911_config(struct mcp3911 *adc, struct device_node *of_node)
204{
205	u32 configreg;
206	int ret;
207
208	of_property_read_u32(of_node, "device-addr", &adc->dev_addr);
209	if (adc->dev_addr > 3) {
210		dev_err(&adc->spi->dev,
211			"invalid device address (%i). Must be in range 0-3.\n",
212			adc->dev_addr);
213		return -EINVAL;
214	}
215	dev_dbg(&adc->spi->dev, "use device address %i\n", adc->dev_addr);
216
217	ret = mcp3911_read(adc, MCP3911_REG_CONFIG, &configreg, 2);
218	if (ret)
219		return ret;
220
221	if (adc->vref) {
222		dev_dbg(&adc->spi->dev, "use external voltage reference\n");
223		configreg |= MCP3911_CONFIG_VREFEXT;
224	} else {
225		dev_dbg(&adc->spi->dev,
226			"use internal voltage reference (1.2V)\n");
227		configreg &= ~MCP3911_CONFIG_VREFEXT;
228	}
229
230	if (adc->clki) {
231		dev_dbg(&adc->spi->dev, "use external clock as clocksource\n");
232		configreg |= MCP3911_CONFIG_CLKEXT;
233	} else {
234		dev_dbg(&adc->spi->dev,
235			"use crystal oscillator as clocksource\n");
236		configreg &= ~MCP3911_CONFIG_CLKEXT;
237	}
238
239	return  mcp3911_write(adc, MCP3911_REG_CONFIG, configreg, 2);
240}
241
242static int mcp3911_probe(struct spi_device *spi)
243{
244	struct iio_dev *indio_dev;
245	struct mcp3911 *adc;
246	int ret;
247
248	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));
249	if (!indio_dev)
250		return -ENOMEM;
251
252	adc = iio_priv(indio_dev);
253	adc->spi = spi;
254
255	adc->vref = devm_regulator_get_optional(&adc->spi->dev, "vref");
256	if (IS_ERR(adc->vref)) {
257		if (PTR_ERR(adc->vref) == -ENODEV) {
258			adc->vref = NULL;
259		} else {
260			dev_err(&adc->spi->dev,
261				"failed to get regulator (%ld)\n",
262				PTR_ERR(adc->vref));
263			return PTR_ERR(adc->vref);
264		}
265
266	} else {
267		ret = regulator_enable(adc->vref);
268		if (ret)
269			return ret;
270	}
271
272	adc->clki = devm_clk_get(&adc->spi->dev, NULL);
273	if (IS_ERR(adc->clki)) {
274		if (PTR_ERR(adc->clki) == -ENOENT) {
275			adc->clki = NULL;
276		} else {
277			dev_err(&adc->spi->dev,
278				"failed to get adc clk (%ld)\n",
279				PTR_ERR(adc->clki));
280			ret = PTR_ERR(adc->clki);
281			goto reg_disable;
282		}
283	} else {
284		ret = clk_prepare_enable(adc->clki);
285		if (ret < 0) {
286			dev_err(&adc->spi->dev,
287				"Failed to enable clki: %d\n", ret);
288			goto reg_disable;
289		}
290	}
291
292	ret = mcp3911_config(adc, spi->dev.of_node);
293	if (ret)
294		goto clk_disable;
295
296	indio_dev->dev.parent = &spi->dev;
297	indio_dev->dev.of_node = spi->dev.of_node;
298	indio_dev->name = spi_get_device_id(spi)->name;
299	indio_dev->modes = INDIO_DIRECT_MODE;
300	indio_dev->info = &mcp3911_info;
301	spi_set_drvdata(spi, indio_dev);
302
303	indio_dev->channels = mcp3911_channels;
304	indio_dev->num_channels = ARRAY_SIZE(mcp3911_channels);
305
306	mutex_init(&adc->lock);
307
308	ret = iio_device_register(indio_dev);
309	if (ret)
310		goto clk_disable;
311
312	return ret;
313
314clk_disable:
315	clk_disable_unprepare(adc->clki);
316reg_disable:
317	if (adc->vref)
318		regulator_disable(adc->vref);
319
320	return ret;
321}
322
323static int mcp3911_remove(struct spi_device *spi)
324{
325	struct iio_dev *indio_dev = spi_get_drvdata(spi);
326	struct mcp3911 *adc = iio_priv(indio_dev);
327
328	iio_device_unregister(indio_dev);
329
330	clk_disable_unprepare(adc->clki);
331	if (adc->vref)
332		regulator_disable(adc->vref);
333
334	return 0;
335}
336
337static const struct of_device_id mcp3911_dt_ids[] = {
338	{ .compatible = "microchip,mcp3911" },
339	{ }
340};
341MODULE_DEVICE_TABLE(of, mcp3911_dt_ids);
342
343static const struct spi_device_id mcp3911_id[] = {
344	{ "mcp3911", 0 },
345	{ }
346};
347MODULE_DEVICE_TABLE(spi, mcp3911_id);
348
349static struct spi_driver mcp3911_driver = {
350	.driver = {
351		.name = "mcp3911",
352		.of_match_table = mcp3911_dt_ids,
353	},
354	.probe = mcp3911_probe,
355	.remove = mcp3911_remove,
356	.id_table = mcp3911_id,
357};
358module_spi_driver(mcp3911_driver);
359
360MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>");
361MODULE_AUTHOR("Kent Gustavsson <kent@minoris.se>");
362MODULE_DESCRIPTION("Microchip Technology MCP3911");
363MODULE_LICENSE("GPL v2");
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Driver for Microchip MCP3911, Two-channel Analog Front End
  4 *
  5 * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com>
  6 * Copyright (C) 2018 Kent Gustavsson <kent@minoris.se>
  7 */
  8#include <linux/clk.h>
  9#include <linux/delay.h>
 10#include <linux/err.h>
 11#include <linux/iio/iio.h>
 12#include <linux/module.h>
 13#include <linux/regulator/consumer.h>
 14#include <linux/spi/spi.h>
 15
 16#define MCP3911_REG_CHANNEL0		0x00
 17#define MCP3911_REG_CHANNEL1		0x03
 18#define MCP3911_REG_MOD			0x06
 19#define MCP3911_REG_PHASE		0x07
 20#define MCP3911_REG_GAIN		0x09
 21
 22#define MCP3911_REG_STATUSCOM		0x0a
 23#define MCP3911_STATUSCOM_CH1_24WIDTH	BIT(4)
 24#define MCP3911_STATUSCOM_CH0_24WIDTH	BIT(3)
 25#define MCP3911_STATUSCOM_EN_OFFCAL	BIT(2)
 26#define MCP3911_STATUSCOM_EN_GAINCAL	BIT(1)
 27
 28#define MCP3911_REG_CONFIG		0x0c
 29#define MCP3911_CONFIG_CLKEXT		BIT(1)
 30#define MCP3911_CONFIG_VREFEXT		BIT(2)
 31
 32#define MCP3911_REG_OFFCAL_CH0		0x0e
 33#define MCP3911_REG_GAINCAL_CH0		0x11
 34#define MCP3911_REG_OFFCAL_CH1		0x14
 35#define MCP3911_REG_GAINCAL_CH1		0x17
 36#define MCP3911_REG_VREFCAL		0x1a
 37
 38#define MCP3911_CHANNEL(x)		(MCP3911_REG_CHANNEL0 + x * 3)
 39#define MCP3911_OFFCAL(x)		(MCP3911_REG_OFFCAL_CH0 + x * 6)
 40
 41/* Internal voltage reference in uV */
 42#define MCP3911_INT_VREF_UV		1200000
 43
 44#define MCP3911_REG_READ(reg, id)	((((reg) << 1) | ((id) << 5) | (1 << 0)) & 0xff)
 45#define MCP3911_REG_WRITE(reg, id)	((((reg) << 1) | ((id) << 5) | (0 << 0)) & 0xff)
 46
 47#define MCP3911_NUM_CHANNELS		2
 48
 49struct mcp3911 {
 50	struct spi_device *spi;
 51	struct mutex lock;
 52	struct regulator *vref;
 53	struct clk *clki;
 54	u32 dev_addr;
 55};
 56
 57static int mcp3911_read(struct mcp3911 *adc, u8 reg, u32 *val, u8 len)
 58{
 59	int ret;
 60
 61	reg = MCP3911_REG_READ(reg, adc->dev_addr);
 62	ret = spi_write_then_read(adc->spi, &reg, 1, val, len);
 63	if (ret < 0)
 64		return ret;
 65
 66	be32_to_cpus(val);
 67	*val >>= ((4 - len) * 8);
 68	dev_dbg(&adc->spi->dev, "reading 0x%x from register 0x%x\n", *val,
 69		reg >> 1);
 70	return ret;
 71}
 72
 73static int mcp3911_write(struct mcp3911 *adc, u8 reg, u32 val, u8 len)
 74{
 75	dev_dbg(&adc->spi->dev, "writing 0x%x to register 0x%x\n", val, reg);
 76
 77	val <<= (3 - len) * 8;
 78	cpu_to_be32s(&val);
 79	val |= MCP3911_REG_WRITE(reg, adc->dev_addr);
 80
 81	return spi_write(adc->spi, &val, len + 1);
 82}
 83
 84static int mcp3911_update(struct mcp3911 *adc, u8 reg, u32 mask,
 85		u32 val, u8 len)
 86{
 87	u32 tmp;
 88	int ret;
 89
 90	ret = mcp3911_read(adc, reg, &tmp, len);
 91	if (ret)
 92		return ret;
 93
 94	val &= mask;
 95	val |= tmp & ~mask;
 96	return mcp3911_write(adc, reg, val, len);
 97}
 98
 99static int mcp3911_read_raw(struct iio_dev *indio_dev,
100			    struct iio_chan_spec const *channel, int *val,
101			    int *val2, long mask)
102{
103	struct mcp3911 *adc = iio_priv(indio_dev);
104	int ret = -EINVAL;
105
106	mutex_lock(&adc->lock);
107	switch (mask) {
108	case IIO_CHAN_INFO_RAW:
109		ret = mcp3911_read(adc,
110				   MCP3911_CHANNEL(channel->channel), val, 3);
111		if (ret)
112			goto out;
113
114		ret = IIO_VAL_INT;
115		break;
116
117	case IIO_CHAN_INFO_OFFSET:
118		ret = mcp3911_read(adc,
119				   MCP3911_OFFCAL(channel->channel), val, 3);
120		if (ret)
121			goto out;
122
123		ret = IIO_VAL_INT;
124		break;
125
126	case IIO_CHAN_INFO_SCALE:
127		if (adc->vref) {
128			ret = regulator_get_voltage(adc->vref);
129			if (ret < 0) {
130				dev_err(indio_dev->dev.parent,
131					"failed to get vref voltage: %d\n",
132				       ret);
133				goto out;
134			}
135
136			*val = ret / 1000;
137		} else {
138			*val = MCP3911_INT_VREF_UV;
139		}
140
141		*val2 = 24;
142		ret = IIO_VAL_FRACTIONAL_LOG2;
143		break;
144	}
145
146out:
147	mutex_unlock(&adc->lock);
148	return ret;
149}
150
151static int mcp3911_write_raw(struct iio_dev *indio_dev,
152			    struct iio_chan_spec const *channel, int val,
153			    int val2, long mask)
154{
155	struct mcp3911 *adc = iio_priv(indio_dev);
156	int ret = -EINVAL;
157
158	mutex_lock(&adc->lock);
159	switch (mask) {
160	case IIO_CHAN_INFO_OFFSET:
161		if (val2 != 0) {
162			ret = -EINVAL;
163			goto out;
164		}
165
166		/* Write offset */
167		ret = mcp3911_write(adc, MCP3911_OFFCAL(channel->channel), val,
168				    3);
169		if (ret)
170			goto out;
171
172		/* Enable offset*/
173		ret = mcp3911_update(adc, MCP3911_REG_STATUSCOM,
174				MCP3911_STATUSCOM_EN_OFFCAL,
175				MCP3911_STATUSCOM_EN_OFFCAL, 2);
176		break;
177	}
178
179out:
180	mutex_unlock(&adc->lock);
181	return ret;
182}
183
184#define MCP3911_CHAN(idx) {					\
185		.type = IIO_VOLTAGE,				\
186		.indexed = 1,					\
187		.channel = idx,					\
188		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |	\
189			BIT(IIO_CHAN_INFO_OFFSET) |		\
190			BIT(IIO_CHAN_INFO_SCALE),		\
191}
192
193static const struct iio_chan_spec mcp3911_channels[] = {
194	MCP3911_CHAN(0),
195	MCP3911_CHAN(1),
196};
197
198static const struct iio_info mcp3911_info = {
199	.read_raw = mcp3911_read_raw,
200	.write_raw = mcp3911_write_raw,
201};
202
203static int mcp3911_config(struct mcp3911 *adc, struct device_node *of_node)
204{
205	u32 configreg;
206	int ret;
207
208	of_property_read_u32(of_node, "device-addr", &adc->dev_addr);
209	if (adc->dev_addr > 3) {
210		dev_err(&adc->spi->dev,
211			"invalid device address (%i). Must be in range 0-3.\n",
212			adc->dev_addr);
213		return -EINVAL;
214	}
215	dev_dbg(&adc->spi->dev, "use device address %i\n", adc->dev_addr);
216
217	ret = mcp3911_read(adc, MCP3911_REG_CONFIG, &configreg, 2);
218	if (ret)
219		return ret;
220
221	if (adc->vref) {
222		dev_dbg(&adc->spi->dev, "use external voltage reference\n");
223		configreg |= MCP3911_CONFIG_VREFEXT;
224	} else {
225		dev_dbg(&adc->spi->dev,
226			"use internal voltage reference (1.2V)\n");
227		configreg &= ~MCP3911_CONFIG_VREFEXT;
228	}
229
230	if (adc->clki) {
231		dev_dbg(&adc->spi->dev, "use external clock as clocksource\n");
232		configreg |= MCP3911_CONFIG_CLKEXT;
233	} else {
234		dev_dbg(&adc->spi->dev,
235			"use crystal oscillator as clocksource\n");
236		configreg &= ~MCP3911_CONFIG_CLKEXT;
237	}
238
239	return  mcp3911_write(adc, MCP3911_REG_CONFIG, configreg, 2);
240}
241
242static int mcp3911_probe(struct spi_device *spi)
243{
244	struct iio_dev *indio_dev;
245	struct mcp3911 *adc;
246	int ret;
247
248	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adc));
249	if (!indio_dev)
250		return -ENOMEM;
251
252	adc = iio_priv(indio_dev);
253	adc->spi = spi;
254
255	adc->vref = devm_regulator_get_optional(&adc->spi->dev, "vref");
256	if (IS_ERR(adc->vref)) {
257		if (PTR_ERR(adc->vref) == -ENODEV) {
258			adc->vref = NULL;
259		} else {
260			dev_err(&adc->spi->dev,
261				"failed to get regulator (%ld)\n",
262				PTR_ERR(adc->vref));
263			return PTR_ERR(adc->vref);
264		}
265
266	} else {
267		ret = regulator_enable(adc->vref);
268		if (ret)
269			return ret;
270	}
271
272	adc->clki = devm_clk_get(&adc->spi->dev, NULL);
273	if (IS_ERR(adc->clki)) {
274		if (PTR_ERR(adc->clki) == -ENOENT) {
275			adc->clki = NULL;
276		} else {
277			dev_err(&adc->spi->dev,
278				"failed to get adc clk (%ld)\n",
279				PTR_ERR(adc->clki));
280			ret = PTR_ERR(adc->clki);
281			goto reg_disable;
282		}
283	} else {
284		ret = clk_prepare_enable(adc->clki);
285		if (ret < 0) {
286			dev_err(&adc->spi->dev,
287				"Failed to enable clki: %d\n", ret);
288			goto reg_disable;
289		}
290	}
291
292	ret = mcp3911_config(adc, spi->dev.of_node);
293	if (ret)
294		goto clk_disable;
295
 
 
296	indio_dev->name = spi_get_device_id(spi)->name;
297	indio_dev->modes = INDIO_DIRECT_MODE;
298	indio_dev->info = &mcp3911_info;
299	spi_set_drvdata(spi, indio_dev);
300
301	indio_dev->channels = mcp3911_channels;
302	indio_dev->num_channels = ARRAY_SIZE(mcp3911_channels);
303
304	mutex_init(&adc->lock);
305
306	ret = iio_device_register(indio_dev);
307	if (ret)
308		goto clk_disable;
309
310	return ret;
311
312clk_disable:
313	clk_disable_unprepare(adc->clki);
314reg_disable:
315	if (adc->vref)
316		regulator_disable(adc->vref);
317
318	return ret;
319}
320
321static int mcp3911_remove(struct spi_device *spi)
322{
323	struct iio_dev *indio_dev = spi_get_drvdata(spi);
324	struct mcp3911 *adc = iio_priv(indio_dev);
325
326	iio_device_unregister(indio_dev);
327
328	clk_disable_unprepare(adc->clki);
329	if (adc->vref)
330		regulator_disable(adc->vref);
331
332	return 0;
333}
334
335static const struct of_device_id mcp3911_dt_ids[] = {
336	{ .compatible = "microchip,mcp3911" },
337	{ }
338};
339MODULE_DEVICE_TABLE(of, mcp3911_dt_ids);
340
341static const struct spi_device_id mcp3911_id[] = {
342	{ "mcp3911", 0 },
343	{ }
344};
345MODULE_DEVICE_TABLE(spi, mcp3911_id);
346
347static struct spi_driver mcp3911_driver = {
348	.driver = {
349		.name = "mcp3911",
350		.of_match_table = mcp3911_dt_ids,
351	},
352	.probe = mcp3911_probe,
353	.remove = mcp3911_remove,
354	.id_table = mcp3911_id,
355};
356module_spi_driver(mcp3911_driver);
357
358MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>");
359MODULE_AUTHOR("Kent Gustavsson <kent@minoris.se>");
360MODULE_DESCRIPTION("Microchip Technology MCP3911");
361MODULE_LICENSE("GPL v2");