xref: /openbmc/linux/drivers/iio/adc/ad7280a.c (revision caf83e49)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * AD7280A Lithium Ion Battery Monitoring System
4  *
5  * Copyright 2011 Analog Devices Inc.
6  */
7 
8 #include <linux/bitfield.h>
9 #include <linux/bits.h>
10 #include <linux/crc8.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/mod_devicetable.h>
18 #include <linux/mutex.h>
19 #include <linux/slab.h>
20 #include <linux/sysfs.h>
21 #include <linux/spi/spi.h>
22 
23 #include <linux/iio/events.h>
24 #include <linux/iio/iio.h>
25 
26 /* Registers */
27 
28 #define AD7280A_CELL_VOLTAGE_1_REG		0x0  /* D11 to D0, Read only */
29 #define AD7280A_CELL_VOLTAGE_2_REG		0x1  /* D11 to D0, Read only */
30 #define AD7280A_CELL_VOLTAGE_3_REG		0x2  /* D11 to D0, Read only */
31 #define AD7280A_CELL_VOLTAGE_4_REG		0x3  /* D11 to D0, Read only */
32 #define AD7280A_CELL_VOLTAGE_5_REG		0x4  /* D11 to D0, Read only */
33 #define AD7280A_CELL_VOLTAGE_6_REG		0x5  /* D11 to D0, Read only */
34 #define AD7280A_AUX_ADC_1_REG			0x6  /* D11 to D0, Read only */
35 #define AD7280A_AUX_ADC_2_REG			0x7  /* D11 to D0, Read only */
36 #define AD7280A_AUX_ADC_3_REG			0x8  /* D11 to D0, Read only */
37 #define AD7280A_AUX_ADC_4_REG			0x9  /* D11 to D0, Read only */
38 #define AD7280A_AUX_ADC_5_REG			0xA  /* D11 to D0, Read only */
39 #define AD7280A_AUX_ADC_6_REG			0xB  /* D11 to D0, Read only */
40 #define AD7280A_SELF_TEST_REG			0xC  /* D11 to D0, Read only */
41 
42 #define AD7280A_CTRL_HB_REG			0xD  /* D15 to D8, Read/write */
43 #define   AD7280A_CTRL_HB_CONV_INPUT_MSK		GENMASK(7, 6)
44 #define     AD7280A_CTRL_HB_CONV_INPUT_ALL			0
45 #define     AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_5		1
46 #define     AD7280A_CTRL_HB_CONV_INPUT_6CELL			2
47 #define     AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST		3
48 #define   AD7280A_CTRL_HB_CONV_RREAD_MSK		GENMASK(5, 4)
49 #define     AD7280A_CTRL_HB_CONV_RREAD_ALL			0
50 #define     AD7280A_CTRL_HB_CONV_RREAD_6CELL_AUX1_3_5		1
51 #define     AD7280A_CTRL_HB_CONV_RREAD_6CELL			2
52 #define     AD7280A_CTRL_HB_CONV_RREAD_NO		        3
53 #define   AD7280A_CTRL_HB_CONV_START_MSK		BIT(3)
54 #define     AD7280A_CTRL_HB_CONV_START_CNVST			0
55 #define     AD7280A_CTRL_HB_CONV_START_CS			1
56 #define   AD7280A_CTRL_HB_CONV_AVG_MSK			GENMASK(2, 1)
57 #define     AD7280A_CTRL_HB_CONV_AVG_DIS			0
58 #define     AD7280A_CTRL_HB_CONV_AVG_2				1
59 #define     AD7280A_CTRL_HB_CONV_AVG_4			        2
60 #define     AD7280A_CTRL_HB_CONV_AVG_8			        3
61 #define   AD7280A_CTRL_HB_PWRDN_SW			BIT(0)
62 
63 #define AD7280A_CTRL_LB_REG			0xE  /* D7 to D0, Read/write */
64 #define   AD7280A_CTRL_LB_SWRST_MSK			BIT(7)
65 #define   AD7280A_CTRL_LB_ACQ_TIME_MSK			GENMASK(6, 5)
66 #define     AD7280A_CTRL_LB_ACQ_TIME_400ns			0
67 #define     AD7280A_CTRL_LB_ACQ_TIME_800ns			1
68 #define     AD7280A_CTRL_LB_ACQ_TIME_1200ns			2
69 #define     AD7280A_CTRL_LB_ACQ_TIME_1600ns			3
70 #define   AD7280A_CTRL_LB_MUST_SET			BIT(4)
71 #define   AD7280A_CTRL_LB_THERMISTOR_MSK		BIT(3)
72 #define   AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK		BIT(2)
73 #define   AD7280A_CTRL_LB_INC_DEV_ADDR_MSK		BIT(1)
74 #define   AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK		BIT(0)
75 
76 #define AD7280A_CELL_OVERVOLTAGE_REG		0xF  /* D7 to D0, Read/write */
77 #define AD7280A_CELL_UNDERVOLTAGE_REG		0x10 /* D7 to D0, Read/write */
78 #define AD7280A_AUX_ADC_OVERVOLTAGE_REG		0x11 /* D7 to D0, Read/write */
79 #define AD7280A_AUX_ADC_UNDERVOLTAGE_REG	0x12 /* D7 to D0, Read/write */
80 
81 #define AD7280A_ALERT_REG			0x13 /* D7 to D0, Read/write */
82 #define   AD7280A_ALERT_REMOVE_MSK			GENMASK(3, 0)
83 #define     AD7280A_ALERT_REMOVE_AUX5			BIT(0)
84 #define     AD7280A_ALERT_REMOVE_AUX3_AUX5		BIT(1)
85 #define     AD7280A_ALERT_REMOVE_VIN5			BIT(2)
86 #define     AD7280A_ALERT_REMOVE_VIN4_VIN5		BIT(3)
87 #define   AD7280A_ALERT_GEN_STATIC_HIGH			BIT(6)
88 #define   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN		(BIT(7) | BIT(6))
89 
90 #define AD7280A_CELL_BALANCE_REG		0x14 /* D7 to D0, Read/write */
91 #define  AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK		GENMASK(7, 2)
92 #define AD7280A_CB1_TIMER_REG			0x15 /* D7 to D0, Read/write */
93 #define  AD7280A_CB_TIMER_VAL_MSK			GENMASK(7, 3)
94 #define AD7280A_CB2_TIMER_REG			0x16 /* D7 to D0, Read/write */
95 #define AD7280A_CB3_TIMER_REG			0x17 /* D7 to D0, Read/write */
96 #define AD7280A_CB4_TIMER_REG			0x18 /* D7 to D0, Read/write */
97 #define AD7280A_CB5_TIMER_REG			0x19 /* D7 to D0, Read/write */
98 #define AD7280A_CB6_TIMER_REG			0x1A /* D7 to D0, Read/write */
99 #define AD7280A_PD_TIMER_REG			0x1B /* D7 to D0, Read/write */
100 #define AD7280A_READ_REG			0x1C /* D7 to D0, Read/write */
101 #define   AD7280A_READ_ADDR_MSK				GENMASK(7, 2)
102 #define AD7280A_CNVST_CTRL_REG			0x1D /* D7 to D0, Read/write */
103 
104 /* Transfer fields */
105 #define AD7280A_TRANS_WRITE_DEVADDR_MSK		GENMASK(31, 27)
106 #define AD7280A_TRANS_WRITE_ADDR_MSK		GENMASK(26, 21)
107 #define AD7280A_TRANS_WRITE_VAL_MSK		GENMASK(20, 13)
108 #define AD7280A_TRANS_WRITE_ALL_MSK		BIT(12)
109 #define AD7280A_TRANS_WRITE_CRC_MSK		GENMASK(10, 3)
110 #define AD7280A_TRANS_WRITE_RES_PATTERN		0x2
111 
112 /* Layouts differ for channel vs other registers */
113 #define AD7280A_TRANS_READ_DEVADDR_MSK		GENMASK(31, 27)
114 #define AD7280A_TRANS_READ_CONV_CHANADDR_MSK	GENMASK(26, 23)
115 #define AD7280A_TRANS_READ_CONV_DATA_MSK	GENMASK(22, 11)
116 #define AD7280A_TRANS_READ_REG_REGADDR_MSK	GENMASK(26, 21)
117 #define AD7280A_TRANS_READ_REG_DATA_MSK		GENMASK(20, 13)
118 #define AD7280A_TRANS_READ_WRITE_ACK_MSK	BIT(10)
119 #define AD7280A_TRANS_READ_CRC_MSK		GENMASK(9, 2)
120 
121 /* Magic value used to indicate this special case */
122 #define AD7280A_ALL_CELLS				(0xAD << 16)
123 
124 #define AD7280A_MAX_SPI_CLK_HZ		700000 /* < 1MHz */
125 #define AD7280A_MAX_CHAIN		8
126 #define AD7280A_CELLS_PER_DEV		6
127 #define AD7280A_BITS			12
128 #define AD7280A_NUM_CH			(AD7280A_AUX_ADC_6_REG - \
129 					AD7280A_CELL_VOLTAGE_1_REG + 1)
130 
131 #define AD7280A_CALC_VOLTAGE_CHAN_NUM(d, c) (((d) * AD7280A_CELLS_PER_DEV) + \
132 					     (c))
133 #define AD7280A_CALC_TEMP_CHAN_NUM(d, c)    (((d) * AD7280A_CELLS_PER_DEV) + \
134 					     (c) - AD7280A_CELLS_PER_DEV)
135 
136 #define AD7280A_DEVADDR_MASTER		0
137 #define AD7280A_DEVADDR_ALL		0x1F
138 
139 static const unsigned short ad7280a_n_avg[4] = {1, 2, 4, 8};
140 static const unsigned short ad7280a_t_acq_ns[4] = {470, 1030, 1510, 1945};
141 
142 /* 5-bit device address is sent LSB first */
143 static unsigned int ad7280a_devaddr(unsigned int addr)
144 {
145 	return ((addr & 0x1) << 4) |
146 	       ((addr & 0x2) << 2) |
147 	       (addr & 0x4) |
148 	       ((addr & 0x8) >> 2) |
149 	       ((addr & 0x10) >> 4);
150 }
151 
152 /*
153  * During a read a valid write is mandatory.
154  * So writing to the highest available address (Address 0x1F) and setting the
155  * address all parts bit to 0 is recommended.
156  * So the TXVAL is AD7280A_DEVADDR_ALL + CRC
157  */
158 #define AD7280A_READ_TXVAL	0xF800030A
159 
160 /*
161  * AD7280 CRC
162  *
163  * P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F
164  */
165 #define POLYNOM		0x2F
166 
167 struct ad7280_state {
168 	struct spi_device		*spi;
169 	struct iio_chan_spec		*channels;
170 	unsigned int			chain_last_alert_ignore;
171 	bool				thermistor_term_en;
172 	int				slave_num;
173 	int				scan_cnt;
174 	int				readback_delay_us;
175 	unsigned char			crc_tab[CRC8_TABLE_SIZE];
176 	u8				oversampling_ratio;
177 	u8				acquisition_time;
178 	unsigned char			ctrl_lb;
179 	unsigned char			cell_threshhigh;
180 	unsigned char			cell_threshlow;
181 	unsigned char			aux_threshhigh;
182 	unsigned char			aux_threshlow;
183 	unsigned char			cb_mask[AD7280A_MAX_CHAIN];
184 	struct mutex			lock; /* protect sensor state */
185 
186 	__be32				tx ____cacheline_aligned;
187 	__be32				rx;
188 };
189 
190 static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned int val)
191 {
192 	unsigned char crc;
193 
194 	crc = crc_tab[val >> 16 & 0xFF];
195 	crc = crc_tab[crc ^ (val >> 8 & 0xFF)];
196 
197 	return crc ^ (val & 0xFF);
198 }
199 
200 static int ad7280_check_crc(struct ad7280_state *st, unsigned int val)
201 {
202 	unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10);
203 
204 	if (crc != ((val >> 2) & 0xFF))
205 		return -EIO;
206 
207 	return 0;
208 }
209 
210 /*
211  * After initiating a conversion sequence we need to wait until the conversion
212  * is done. The delay is typically in the range of 15..30us however depending on
213  * the number of devices in the daisy chain, the number of averages taken,
214  * conversion delays and acquisition time options it may take up to 250us, in
215  * this case we better sleep instead of busy wait.
216  */
217 
218 static void ad7280_delay(struct ad7280_state *st)
219 {
220 	if (st->readback_delay_us < 50)
221 		udelay(st->readback_delay_us);
222 	else
223 		usleep_range(250, 500);
224 }
225 
226 static int __ad7280_read32(struct ad7280_state *st, unsigned int *val)
227 {
228 	int ret;
229 	struct spi_transfer t = {
230 		.tx_buf	= &st->tx,
231 		.rx_buf = &st->rx,
232 		.len = sizeof(st->tx),
233 	};
234 
235 	st->tx = cpu_to_be32(AD7280A_READ_TXVAL);
236 
237 	ret = spi_sync_transfer(st->spi, &t, 1);
238 	if (ret)
239 		return ret;
240 
241 	*val = be32_to_cpu(st->rx);
242 
243 	return 0;
244 }
245 
246 static int ad7280_write(struct ad7280_state *st, unsigned int devaddr,
247 			unsigned int addr, bool all, unsigned int val)
248 {
249 	unsigned int reg = FIELD_PREP(AD7280A_TRANS_WRITE_DEVADDR_MSK, devaddr) |
250 		FIELD_PREP(AD7280A_TRANS_WRITE_ADDR_MSK, addr) |
251 		FIELD_PREP(AD7280A_TRANS_WRITE_VAL_MSK, val) |
252 		FIELD_PREP(AD7280A_TRANS_WRITE_ALL_MSK, all);
253 
254 	reg |= FIELD_PREP(AD7280A_TRANS_WRITE_CRC_MSK,
255 			ad7280_calc_crc8(st->crc_tab, reg >> 11));
256 	/* Reserved b010 pattern not included crc calc */
257 	reg |= AD7280A_TRANS_WRITE_RES_PATTERN;
258 
259 	st->tx = cpu_to_be32(reg);
260 
261 	return spi_write(st->spi, &st->tx, sizeof(st->tx));
262 }
263 
264 static int ad7280_read_reg(struct ad7280_state *st, unsigned int devaddr,
265 			   unsigned int addr)
266 {
267 	int ret;
268 	unsigned int tmp;
269 
270 	/* turns off the read operation on all parts */
271 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
272 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
273 				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |
274 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
275 				      AD7280A_CTRL_HB_CONV_RREAD_NO) |
276 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
277 				      st->oversampling_ratio));
278 	if (ret)
279 		return ret;
280 
281 	/* turns on the read operation on the addressed part */
282 	ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0,
283 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
284 				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |
285 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
286 				      AD7280A_CTRL_HB_CONV_RREAD_ALL) |
287 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
288 				      st->oversampling_ratio));
289 	if (ret)
290 		return ret;
291 
292 	/* Set register address on the part to be read from */
293 	ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0,
294 			   FIELD_PREP(AD7280A_READ_ADDR_MSK, addr));
295 	if (ret)
296 		return ret;
297 
298 	ret = __ad7280_read32(st, &tmp);
299 	if (ret)
300 		return ret;
301 
302 	if (ad7280_check_crc(st, tmp))
303 		return -EIO;
304 
305 	if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) ||
306 	    (FIELD_GET(AD7280A_TRANS_READ_REG_REGADDR_MSK, tmp) != addr))
307 		return -EFAULT;
308 
309 	return FIELD_GET(AD7280A_TRANS_READ_REG_DATA_MSK, tmp);
310 }
311 
312 static int ad7280_read_channel(struct ad7280_state *st, unsigned int devaddr,
313 			       unsigned int addr)
314 {
315 	int ret;
316 	unsigned int tmp;
317 
318 	ret = ad7280_write(st, devaddr, AD7280A_READ_REG, 0,
319 			   FIELD_PREP(AD7280A_READ_ADDR_MSK, addr));
320 	if (ret)
321 		return ret;
322 
323 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
324 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
325 				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |
326 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
327 				      AD7280A_CTRL_HB_CONV_RREAD_NO) |
328 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
329 				      st->oversampling_ratio));
330 	if (ret)
331 		return ret;
332 
333 	ret = ad7280_write(st, devaddr, AD7280A_CTRL_HB_REG, 0,
334 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
335 				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |
336 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
337 				      AD7280A_CTRL_HB_CONV_RREAD_ALL) |
338 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK,
339 				      AD7280A_CTRL_HB_CONV_START_CS) |
340 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
341 				      st->oversampling_ratio));
342 	if (ret)
343 		return ret;
344 
345 	ad7280_delay(st);
346 
347 	ret = __ad7280_read32(st, &tmp);
348 	if (ret)
349 		return ret;
350 
351 	if (ad7280_check_crc(st, tmp))
352 		return -EIO;
353 
354 	if ((FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, tmp) != devaddr) ||
355 	    (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) != addr))
356 		return -EFAULT;
357 
358 	return FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp);
359 }
360 
361 static int ad7280_read_all_channels(struct ad7280_state *st, unsigned int cnt,
362 				    unsigned int *array)
363 {
364 	int i, ret;
365 	unsigned int tmp, sum = 0;
366 
367 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1,
368 			   AD7280A_CELL_VOLTAGE_1_REG << 2);
369 	if (ret)
370 		return ret;
371 
372 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
373 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_INPUT_MSK,
374 				      AD7280A_CTRL_HB_CONV_INPUT_ALL) |
375 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_RREAD_MSK,
376 				      AD7280A_CTRL_HB_CONV_RREAD_ALL) |
377 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_START_MSK,
378 				      AD7280A_CTRL_HB_CONV_START_CS) |
379 			   FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK,
380 				      st->oversampling_ratio));
381 	if (ret)
382 		return ret;
383 
384 	ad7280_delay(st);
385 
386 	for (i = 0; i < cnt; i++) {
387 		ret = __ad7280_read32(st, &tmp);
388 		if (ret)
389 			return ret;
390 
391 		if (ad7280_check_crc(st, tmp))
392 			return -EIO;
393 
394 		if (array)
395 			array[i] = tmp;
396 		/* only sum cell voltages */
397 		if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, tmp) <=
398 		    AD7280A_CELL_VOLTAGE_6_REG)
399 			sum += FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, tmp);
400 	}
401 
402 	return sum;
403 }
404 
405 static void ad7280_sw_power_down(void *data)
406 {
407 	struct ad7280_state *st = data;
408 
409 	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
410 		     AD7280A_CTRL_HB_PWRDN_SW |
411 		     FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio));
412 }
413 
414 static int ad7280_chain_setup(struct ad7280_state *st)
415 {
416 	unsigned int val, n;
417 	int ret;
418 
419 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1,
420 			   FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) |
421 			   FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) |
422 			   AD7280A_CTRL_LB_MUST_SET |
423 			   FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 1) |
424 			   st->ctrl_lb);
425 	if (ret)
426 		return ret;
427 
428 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_LB_REG, 1,
429 			   FIELD_PREP(AD7280A_CTRL_LB_DAISY_CHAIN_RB_MSK, 1) |
430 			   FIELD_PREP(AD7280A_CTRL_LB_LOCK_DEV_ADDR_MSK, 1) |
431 			   AD7280A_CTRL_LB_MUST_SET |
432 			   FIELD_PREP(AD7280A_CTRL_LB_SWRST_MSK, 0) |
433 			   st->ctrl_lb);
434 	if (ret)
435 		goto error_power_down;
436 
437 	ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ_REG, 1,
438 			   FIELD_PREP(AD7280A_READ_ADDR_MSK, AD7280A_CTRL_LB_REG));
439 	if (ret)
440 		goto error_power_down;
441 
442 	for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
443 		ret = __ad7280_read32(st, &val);
444 		if (ret)
445 			goto error_power_down;
446 
447 		if (val == 0)
448 			return n - 1;
449 
450 		if (ad7280_check_crc(st, val)) {
451 			ret = -EIO;
452 			goto error_power_down;
453 		}
454 
455 		if (n != ad7280a_devaddr(FIELD_GET(AD7280A_TRANS_READ_DEVADDR_MSK, val))) {
456 			ret = -EIO;
457 			goto error_power_down;
458 		}
459 	}
460 	ret = -EFAULT;
461 
462 error_power_down:
463 	ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CTRL_HB_REG, 1,
464 		     AD7280A_CTRL_HB_PWRDN_SW |
465 		     FIELD_PREP(AD7280A_CTRL_HB_CONV_AVG_MSK, st->oversampling_ratio));
466 
467 	return ret;
468 }
469 
470 static ssize_t ad7280_show_balance_sw(struct iio_dev *indio_dev,
471 				      uintptr_t private,
472 				      const struct iio_chan_spec *chan, char *buf)
473 {
474 	struct ad7280_state *st = iio_priv(indio_dev);
475 
476 	return sysfs_emit(buf, "%d\n",
477 			  !!(st->cb_mask[chan->address >> 8] &
478 			     BIT(chan->address & 0xFF)));
479 }
480 
481 static ssize_t ad7280_store_balance_sw(struct iio_dev *indio_dev,
482 				       uintptr_t private,
483 				       const struct iio_chan_spec *chan,
484 				       const char *buf, size_t len)
485 {
486 	struct ad7280_state *st = iio_priv(indio_dev);
487 	unsigned int devaddr, ch;
488 	bool readin;
489 	int ret;
490 
491 	ret = strtobool(buf, &readin);
492 	if (ret)
493 		return ret;
494 
495 	devaddr = chan->address >> 8;
496 	ch = chan->address & 0xFF;
497 
498 	mutex_lock(&st->lock);
499 	if (readin)
500 		st->cb_mask[devaddr] |= BIT(ch);
501 	else
502 		st->cb_mask[devaddr] &= ~BIT(ch);
503 
504 	ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE_REG, 0,
505 			   FIELD_PREP(AD7280A_CELL_BALANCE_CHAN_BITMAP_MSK,
506 				      st->cb_mask[devaddr]));
507 	mutex_unlock(&st->lock);
508 
509 	return ret ? ret : len;
510 }
511 
512 static ssize_t ad7280_show_balance_timer(struct iio_dev *indio_dev,
513 					 uintptr_t private,
514 					 const struct iio_chan_spec *chan,
515 					 char *buf)
516 {
517 	struct ad7280_state *st = iio_priv(indio_dev);
518 	unsigned int msecs;
519 	int ret;
520 
521 	mutex_lock(&st->lock);
522 	ret = ad7280_read_reg(st, chan->address >> 8,
523 			      (chan->address & 0xFF) + AD7280A_CB1_TIMER_REG);
524 	mutex_unlock(&st->lock);
525 
526 	if (ret < 0)
527 		return ret;
528 
529 	msecs = FIELD_GET(AD7280A_CB_TIMER_VAL_MSK, ret) * 71500;
530 
531 	return sysfs_emit(buf, "%u.%u\n", msecs / 1000, msecs % 1000);
532 }
533 
534 static ssize_t ad7280_store_balance_timer(struct iio_dev *indio_dev,
535 					  uintptr_t private,
536 					  const struct iio_chan_spec *chan,
537 					  const char *buf, size_t len)
538 {
539 	struct ad7280_state *st = iio_priv(indio_dev);
540 	int val, val2;
541 	int ret;
542 
543 	ret = iio_str_to_fixpoint(buf, 1000, &val, &val2);
544 	if (ret)
545 		return ret;
546 
547 	val = val * 1000 + val2;
548 	val /= 71500;
549 
550 	if (val > 31)
551 		return -EINVAL;
552 
553 	mutex_lock(&st->lock);
554 	ret = ad7280_write(st, chan->address >> 8,
555 			   (chan->address & 0xFF) + AD7280A_CB1_TIMER_REG, 0,
556 			   FIELD_PREP(AD7280A_CB_TIMER_VAL_MSK, val));
557 	mutex_unlock(&st->lock);
558 
559 	return ret ? ret : len;
560 }
561 
562 static const struct iio_chan_spec_ext_info ad7280_cell_ext_info[] = {
563 	{
564 		.name = "balance_switch_en",
565 		.read = ad7280_show_balance_sw,
566 		.write = ad7280_store_balance_sw,
567 		.shared = IIO_SEPARATE,
568 	}, {
569 		.name = "balance_switch_timer",
570 		.read = ad7280_show_balance_timer,
571 		.write = ad7280_store_balance_timer,
572 		.shared = IIO_SEPARATE,
573 	},
574 	{}
575 };
576 
577 static const struct iio_event_spec ad7280_events[] = {
578 	{
579 		.type = IIO_EV_TYPE_THRESH,
580 		.dir = IIO_EV_DIR_RISING,
581 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
582 	}, {
583 		.type = IIO_EV_TYPE_THRESH,
584 		.dir = IIO_EV_DIR_FALLING,
585 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE),
586 	},
587 };
588 
589 static void ad7280_voltage_channel_init(struct iio_chan_spec *chan, int i,
590 					bool irq_present)
591 {
592 	chan->type = IIO_VOLTAGE;
593 	chan->differential = 1;
594 	chan->channel = i;
595 	chan->channel2 = chan->channel + 1;
596 	if (irq_present) {
597 		chan->event_spec = ad7280_events;
598 		chan->num_event_specs = ARRAY_SIZE(ad7280_events);
599 	}
600 	chan->ext_info = ad7280_cell_ext_info;
601 }
602 
603 static void ad7280_temp_channel_init(struct iio_chan_spec *chan, int i,
604 				     bool irq_present)
605 {
606 	chan->type = IIO_TEMP;
607 	chan->channel = i;
608 	if (irq_present) {
609 		chan->event_spec = ad7280_events;
610 		chan->num_event_specs = ARRAY_SIZE(ad7280_events);
611 	}
612 }
613 
614 static void ad7280_common_fields_init(struct iio_chan_spec *chan, int addr,
615 				      int cnt)
616 {
617 	chan->indexed = 1;
618 	chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
619 	chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
620 	chan->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);
621 	chan->address = addr;
622 	chan->scan_index = cnt;
623 	chan->scan_type.sign = 'u';
624 	chan->scan_type.realbits = 12;
625 	chan->scan_type.storagebits = 32;
626 }
627 
628 static void ad7280_total_voltage_channel_init(struct iio_chan_spec *chan,
629 					      int cnt, int dev)
630 {
631 	chan->type = IIO_VOLTAGE;
632 	chan->differential = 1;
633 	chan->channel = 0;
634 	chan->channel2 = dev * AD7280A_CELLS_PER_DEV;
635 	chan->address = AD7280A_ALL_CELLS;
636 	chan->indexed = 1;
637 	chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
638 	chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
639 	chan->scan_index = cnt;
640 	chan->scan_type.sign = 'u';
641 	chan->scan_type.realbits = 32;
642 	chan->scan_type.storagebits = 32;
643 }
644 
645 static void ad7280_init_dev_channels(struct ad7280_state *st, int dev, int *cnt,
646 				     bool irq_present)
647 {
648 	int addr, ch, i;
649 	struct iio_chan_spec *chan;
650 
651 	for (ch = AD7280A_CELL_VOLTAGE_1_REG; ch <= AD7280A_AUX_ADC_6_REG; ch++) {
652 		chan = &st->channels[*cnt];
653 
654 		if (ch < AD7280A_AUX_ADC_1_REG) {
655 			i = AD7280A_CALC_VOLTAGE_CHAN_NUM(dev, ch);
656 			ad7280_voltage_channel_init(chan, i, irq_present);
657 		} else {
658 			i = AD7280A_CALC_TEMP_CHAN_NUM(dev, ch);
659 			ad7280_temp_channel_init(chan, i, irq_present);
660 		}
661 
662 		addr = ad7280a_devaddr(dev) << 8 | ch;
663 		ad7280_common_fields_init(chan, addr, *cnt);
664 
665 		(*cnt)++;
666 	}
667 }
668 
669 static int ad7280_channel_init(struct ad7280_state *st, bool irq_present)
670 {
671 	int dev, cnt = 0;
672 
673 	st->channels = devm_kcalloc(&st->spi->dev, (st->slave_num + 1) * 12 + 1,
674 				    sizeof(*st->channels), GFP_KERNEL);
675 	if (!st->channels)
676 		return -ENOMEM;
677 
678 	for (dev = 0; dev <= st->slave_num; dev++)
679 		ad7280_init_dev_channels(st, dev, &cnt, irq_present);
680 
681 	ad7280_total_voltage_channel_init(&st->channels[cnt], cnt, dev);
682 
683 	return cnt + 1;
684 }
685 
686 static int ad7280a_read_thresh(struct iio_dev *indio_dev,
687 			       const struct iio_chan_spec *chan,
688 			       enum iio_event_type type,
689 			       enum iio_event_direction dir,
690 			       enum iio_event_info info, int *val, int *val2)
691 {
692 	struct ad7280_state *st = iio_priv(indio_dev);
693 
694 	switch (chan->type) {
695 	case IIO_VOLTAGE:
696 		switch (dir) {
697 		case IIO_EV_DIR_RISING:
698 			*val = 1000 + (st->cell_threshhigh * 1568L) / 100;
699 			return IIO_VAL_INT;
700 		case IIO_EV_DIR_FALLING:
701 			*val = 1000 + (st->cell_threshlow * 1568L) / 100;
702 			return IIO_VAL_INT;
703 		default:
704 			return -EINVAL;
705 		}
706 		break;
707 	case IIO_TEMP:
708 		switch (dir) {
709 		case IIO_EV_DIR_RISING:
710 			*val = ((st->aux_threshhigh) * 196L) / 10;
711 			return IIO_VAL_INT;
712 		case IIO_EV_DIR_FALLING:
713 			*val = (st->aux_threshlow * 196L) / 10;
714 			return IIO_VAL_INT;
715 		default:
716 			return -EINVAL;
717 		}
718 		break;
719 	default:
720 		return -EINVAL;
721 	}
722 }
723 
724 static int ad7280a_write_thresh(struct iio_dev *indio_dev,
725 				const struct iio_chan_spec *chan,
726 				enum iio_event_type type,
727 				enum iio_event_direction dir,
728 				enum iio_event_info info,
729 				int val, int val2)
730 {
731 	struct ad7280_state *st = iio_priv(indio_dev);
732 	unsigned int addr;
733 	long value;
734 	int ret;
735 
736 	if (val2 != 0)
737 		return -EINVAL;
738 
739 	mutex_lock(&st->lock);
740 	switch (chan->type) {
741 	case IIO_VOLTAGE:
742 		value = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
743 		value = clamp(value, 0L, 0xFFL);
744 		switch (dir) {
745 		case IIO_EV_DIR_RISING:
746 			addr = AD7280A_CELL_OVERVOLTAGE_REG;
747 			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
748 					   1, val);
749 			if (ret)
750 				break;
751 			st->cell_threshhigh = value;
752 			break;
753 		case IIO_EV_DIR_FALLING:
754 			addr = AD7280A_CELL_UNDERVOLTAGE_REG;
755 			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
756 					   1, val);
757 			if (ret)
758 				break;
759 			st->cell_threshlow = value;
760 			break;
761 		default:
762 			ret = -EINVAL;
763 			goto err_unlock;
764 		}
765 		break;
766 	case IIO_TEMP:
767 		value = (val * 10) / 196; /* LSB 19.6mV */
768 		value = clamp(value, 0L, 0xFFL);
769 		switch (dir) {
770 		case IIO_EV_DIR_RISING:
771 			addr = AD7280A_AUX_ADC_OVERVOLTAGE_REG;
772 			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
773 					   1, val);
774 			if (ret)
775 				break;
776 			st->aux_threshhigh = val;
777 			break;
778 		case IIO_EV_DIR_FALLING:
779 			addr = AD7280A_AUX_ADC_UNDERVOLTAGE_REG;
780 			ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, addr,
781 					   1, val);
782 			if (ret)
783 				break;
784 			st->aux_threshlow = val;
785 			break;
786 		default:
787 			ret = -EINVAL;
788 			goto err_unlock;
789 		}
790 		break;
791 	default:
792 		ret = -EINVAL;
793 		goto err_unlock;
794 	}
795 
796 err_unlock:
797 	mutex_unlock(&st->lock);
798 
799 	return ret;
800 }
801 
802 static irqreturn_t ad7280_event_handler(int irq, void *private)
803 {
804 	struct iio_dev *indio_dev = private;
805 	struct ad7280_state *st = iio_priv(indio_dev);
806 	unsigned int *channels;
807 	int i, ret;
808 
809 	channels = kcalloc(st->scan_cnt, sizeof(*channels), GFP_KERNEL);
810 	if (!channels)
811 		return IRQ_HANDLED;
812 
813 	ret = ad7280_read_all_channels(st, st->scan_cnt, channels);
814 	if (ret < 0)
815 		goto out;
816 
817 	for (i = 0; i < st->scan_cnt; i++) {
818 		unsigned int val;
819 
820 		val = FIELD_GET(AD7280A_TRANS_READ_CONV_DATA_MSK, channels[i]);
821 		if (FIELD_GET(AD7280A_TRANS_READ_CONV_CHANADDR_MSK, channels[i]) <=
822 		    AD7280A_CELL_VOLTAGE_6_REG) {
823 			if (val >= st->cell_threshhigh) {
824 				u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0,
825 							 IIO_EV_DIR_RISING,
826 							 IIO_EV_TYPE_THRESH,
827 							 0, 0, 0);
828 				iio_push_event(indio_dev, tmp,
829 					       iio_get_time_ns(indio_dev));
830 			} else if (val <= st->cell_threshlow) {
831 				u64 tmp = IIO_EVENT_CODE(IIO_VOLTAGE, 1, 0,
832 							 IIO_EV_DIR_FALLING,
833 							 IIO_EV_TYPE_THRESH,
834 							 0, 0, 0);
835 				iio_push_event(indio_dev, tmp,
836 					       iio_get_time_ns(indio_dev));
837 			}
838 		} else {
839 			if (val >= st->aux_threshhigh) {
840 				u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,
841 							IIO_EV_TYPE_THRESH,
842 							IIO_EV_DIR_RISING);
843 				iio_push_event(indio_dev, tmp,
844 					       iio_get_time_ns(indio_dev));
845 			} else if (val <= st->aux_threshlow) {
846 				u64 tmp = IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,
847 							IIO_EV_TYPE_THRESH,
848 							IIO_EV_DIR_FALLING);
849 				iio_push_event(indio_dev, tmp,
850 					       iio_get_time_ns(indio_dev));
851 			}
852 		}
853 	}
854 
855 out:
856 	kfree(channels);
857 
858 	return IRQ_HANDLED;
859 }
860 
861 static void ad7280_update_delay(struct ad7280_state *st)
862 {
863 	/*
864 	 * Total Conversion Time = ((tACQ + tCONV) *
865 	 *			   (Number of Conversions per Part)) −
866 	 *			   tACQ + ((N - 1) * tDELAY)
867 	 *
868 	 * Readback Delay = Total Conversion Time + tWAIT
869 	 */
870 
871 	st->readback_delay_us =
872 		((ad7280a_t_acq_ns[st->acquisition_time & 0x3] + 720) *
873 			(AD7280A_NUM_CH * ad7280a_n_avg[st->oversampling_ratio & 0x3])) -
874 		ad7280a_t_acq_ns[st->acquisition_time & 0x3] + st->slave_num * 250;
875 
876 	/* Convert to usecs */
877 	st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000);
878 	st->readback_delay_us += 5; /* Add tWAIT */
879 }
880 
881 static int ad7280_read_raw(struct iio_dev *indio_dev,
882 			   struct iio_chan_spec const *chan,
883 			   int *val,
884 			   int *val2,
885 			   long m)
886 {
887 	struct ad7280_state *st = iio_priv(indio_dev);
888 	int ret;
889 
890 	switch (m) {
891 	case IIO_CHAN_INFO_RAW:
892 		mutex_lock(&st->lock);
893 		if (chan->address == AD7280A_ALL_CELLS)
894 			ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
895 		else
896 			ret = ad7280_read_channel(st, chan->address >> 8,
897 						  chan->address & 0xFF);
898 		mutex_unlock(&st->lock);
899 
900 		if (ret < 0)
901 			return ret;
902 
903 		*val = ret;
904 
905 		return IIO_VAL_INT;
906 	case IIO_CHAN_INFO_SCALE:
907 		if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6_REG)
908 			*val = 4000;
909 		else
910 			*val = 5000;
911 
912 		*val2 = AD7280A_BITS;
913 		return IIO_VAL_FRACTIONAL_LOG2;
914 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
915 		*val = ad7280a_n_avg[st->oversampling_ratio];
916 		return IIO_VAL_INT;
917 	}
918 	return -EINVAL;
919 }
920 
921 static int ad7280_write_raw(struct iio_dev *indio_dev,
922 			    struct iio_chan_spec const *chan,
923 			    int val, int val2, long mask)
924 {
925 	struct ad7280_state *st = iio_priv(indio_dev);
926 	int i;
927 
928 	switch (mask) {
929 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
930 		if (val2 != 0)
931 			return -EINVAL;
932 		for (i = 0; i < ARRAY_SIZE(ad7280a_n_avg); i++) {
933 			if (val == ad7280a_n_avg[i]) {
934 				st->oversampling_ratio = i;
935 				ad7280_update_delay(st);
936 				return 0;
937 			}
938 		}
939 		return -EINVAL;
940 	default:
941 		return -EINVAL;
942 	}
943 }
944 
945 static const struct iio_info ad7280_info = {
946 	.read_raw = ad7280_read_raw,
947 	.write_raw = ad7280_write_raw,
948 	.read_event_value = &ad7280a_read_thresh,
949 	.write_event_value = &ad7280a_write_thresh,
950 };
951 
952 static const struct iio_info ad7280_info_no_irq = {
953 	.read_raw = ad7280_read_raw,
954 	.write_raw = ad7280_write_raw,
955 };
956 
957 static int ad7280_probe(struct spi_device *spi)
958 {
959 	struct device *dev = &spi->dev;
960 	struct ad7280_state *st;
961 	int ret;
962 	struct iio_dev *indio_dev;
963 
964 	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
965 	if (!indio_dev)
966 		return -ENOMEM;
967 
968 	st = iio_priv(indio_dev);
969 	spi_set_drvdata(spi, indio_dev);
970 	st->spi = spi;
971 	mutex_init(&st->lock);
972 
973 	st->thermistor_term_en =
974 		device_property_read_bool(dev, "adi,thermistor-termination");
975 
976 	if (device_property_present(dev, "adi,acquisition-time-ns")) {
977 		u32 val;
978 
979 		ret = device_property_read_u32(dev, "adi,acquisition-time-ns", &val);
980 		if (ret)
981 			return ret;
982 
983 		switch (val) {
984 		case 400:
985 			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns;
986 			break;
987 		case 800:
988 			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_800ns;
989 			break;
990 		case 1200:
991 			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1200ns;
992 			break;
993 		case 1600:
994 			st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_1600ns;
995 			break;
996 		default:
997 			dev_err(dev, "Firmware provided acquisition time is invalid\n");
998 			return -EINVAL;
999 		}
1000 	} else {
1001 		st->acquisition_time = AD7280A_CTRL_LB_ACQ_TIME_400ns;
1002 	}
1003 
1004 	/* Alert masks are intended for when particular inputs are not wired up */
1005 	if (device_property_present(dev, "adi,voltage-alert-last-chan")) {
1006 		u32 val;
1007 
1008 		ret = device_property_read_u32(dev, "adi,voltage-alert-last-chan", &val);
1009 		if (ret)
1010 			return ret;
1011 
1012 		switch (val) {
1013 		case 3:
1014 			st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN4_VIN5;
1015 			break;
1016 		case 4:
1017 			st->chain_last_alert_ignore |= AD7280A_ALERT_REMOVE_VIN5;
1018 			break;
1019 		case 5:
1020 			break;
1021 		default:
1022 			dev_err(dev,
1023 				"Firmware provided last voltage alert channel invalid\n");
1024 			break;
1025 		}
1026 	}
1027 	crc8_populate_msb(st->crc_tab, POLYNOM);
1028 
1029 	st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_HZ;
1030 	st->spi->mode = SPI_MODE_1;
1031 	spi_setup(st->spi);
1032 
1033 	st->ctrl_lb = FIELD_PREP(AD7280A_CTRL_LB_ACQ_TIME_MSK, st->acquisition_time) |
1034 		FIELD_PREP(AD7280A_CTRL_LB_THERMISTOR_MSK, st->thermistor_term_en);
1035 	st->oversampling_ratio = 0; /* No oversampling */
1036 
1037 	ret = ad7280_chain_setup(st);
1038 	if (ret < 0)
1039 		return ret;
1040 
1041 	st->slave_num = ret;
1042 	st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
1043 	st->cell_threshhigh = 0xFF;
1044 	st->aux_threshhigh = 0xFF;
1045 
1046 	ret = devm_add_action_or_reset(dev, ad7280_sw_power_down, st);
1047 	if (ret)
1048 		return ret;
1049 
1050 	ad7280_update_delay(st);
1051 
1052 	indio_dev->name = spi_get_device_id(spi)->name;
1053 	indio_dev->modes = INDIO_DIRECT_MODE;
1054 
1055 	ret = ad7280_channel_init(st, spi->irq > 0);
1056 	if (ret < 0)
1057 		return ret;
1058 
1059 	indio_dev->num_channels = ret;
1060 	indio_dev->channels = st->channels;
1061 	if (spi->irq > 0) {
1062 		ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
1063 				   AD7280A_ALERT_REG, 1,
1064 				   AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
1065 		if (ret)
1066 			return ret;
1067 
1068 		ret = ad7280_write(st, ad7280a_devaddr(st->slave_num),
1069 				   AD7280A_ALERT_REG, 0,
1070 				   AD7280A_ALERT_GEN_STATIC_HIGH |
1071 				   FIELD_PREP(AD7280A_ALERT_REMOVE_MSK,
1072 					      st->chain_last_alert_ignore));
1073 		if (ret)
1074 			return ret;
1075 
1076 		ret = devm_request_threaded_irq(dev, spi->irq,
1077 						NULL,
1078 						ad7280_event_handler,
1079 						IRQF_TRIGGER_FALLING |
1080 						IRQF_ONESHOT,
1081 						indio_dev->name,
1082 						indio_dev);
1083 		if (ret)
1084 			return ret;
1085 
1086 		indio_dev->info = &ad7280_info;
1087 	} else {
1088 		indio_dev->info = &ad7280_info_no_irq;
1089 	}
1090 
1091 	return devm_iio_device_register(dev, indio_dev);
1092 }
1093 
1094 static const struct spi_device_id ad7280_id[] = {
1095 	{"ad7280a", 0},
1096 	{}
1097 };
1098 MODULE_DEVICE_TABLE(spi, ad7280_id);
1099 
1100 static struct spi_driver ad7280_driver = {
1101 	.driver = {
1102 		.name	= "ad7280",
1103 	},
1104 	.probe		= ad7280_probe,
1105 	.id_table	= ad7280_id,
1106 };
1107 module_spi_driver(ad7280_driver);
1108 
1109 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1110 MODULE_DESCRIPTION("Analog Devices AD7280A");
1111 MODULE_LICENSE("GPL v2");
1112