xref: /openbmc/linux/drivers/iio/frequency/ad9523.c (revision 22b6e7f3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AD9523 SPI Low Jitter Clock Generator
4  *
5  * Copyright 2012 Analog Devices Inc.
6  */
7 
8 #include <linux/device.h>
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/sysfs.h>
12 #include <linux/spi/spi.h>
13 #include <linux/regulator/consumer.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/err.h>
16 #include <linux/module.h>
17 #include <linux/delay.h>
18 
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/iio/frequency/ad9523.h>
22 
23 #define AD9523_READ	(1 << 15)
24 #define AD9523_WRITE	(0 << 15)
25 #define AD9523_CNT(x)	(((x) - 1) << 13)
26 #define AD9523_ADDR(x)	((x) & 0xFFF)
27 
28 #define AD9523_R1B	(1 << 16)
29 #define AD9523_R2B	(2 << 16)
30 #define AD9523_R3B	(3 << 16)
31 #define AD9523_TRANSF_LEN(x)			((x) >> 16)
32 
33 #define AD9523_SERIAL_PORT_CONFIG		(AD9523_R1B | 0x0)
34 #define AD9523_VERSION_REGISTER			(AD9523_R1B | 0x2)
35 #define AD9523_PART_REGISTER			(AD9523_R1B | 0x3)
36 #define AD9523_READBACK_CTRL			(AD9523_R1B | 0x4)
37 
38 #define AD9523_EEPROM_CUSTOMER_VERSION_ID	(AD9523_R2B | 0x6)
39 
40 #define AD9523_PLL1_REF_A_DIVIDER		(AD9523_R2B | 0x11)
41 #define AD9523_PLL1_REF_B_DIVIDER		(AD9523_R2B | 0x13)
42 #define AD9523_PLL1_REF_TEST_DIVIDER		(AD9523_R1B | 0x14)
43 #define AD9523_PLL1_FEEDBACK_DIVIDER		(AD9523_R2B | 0x17)
44 #define AD9523_PLL1_CHARGE_PUMP_CTRL		(AD9523_R2B | 0x19)
45 #define AD9523_PLL1_INPUT_RECEIVERS_CTRL	(AD9523_R1B | 0x1A)
46 #define AD9523_PLL1_REF_CTRL			(AD9523_R1B | 0x1B)
47 #define AD9523_PLL1_MISC_CTRL			(AD9523_R1B | 0x1C)
48 #define AD9523_PLL1_LOOP_FILTER_CTRL		(AD9523_R1B | 0x1D)
49 
50 #define AD9523_PLL2_CHARGE_PUMP			(AD9523_R1B | 0xF0)
51 #define AD9523_PLL2_FEEDBACK_DIVIDER_AB		(AD9523_R1B | 0xF1)
52 #define AD9523_PLL2_CTRL			(AD9523_R1B | 0xF2)
53 #define AD9523_PLL2_VCO_CTRL			(AD9523_R1B | 0xF3)
54 #define AD9523_PLL2_VCO_DIVIDER			(AD9523_R1B | 0xF4)
55 #define AD9523_PLL2_LOOP_FILTER_CTRL		(AD9523_R2B | 0xF6)
56 #define AD9523_PLL2_R2_DIVIDER			(AD9523_R1B | 0xF7)
57 
58 #define AD9523_CHANNEL_CLOCK_DIST(ch)		(AD9523_R3B | (0x192 + 3 * ch))
59 
60 #define AD9523_PLL1_OUTPUT_CTRL			(AD9523_R1B | 0x1BA)
61 #define AD9523_PLL1_OUTPUT_CHANNEL_CTRL		(AD9523_R1B | 0x1BB)
62 
63 #define AD9523_READBACK_0			(AD9523_R1B | 0x22C)
64 #define AD9523_READBACK_1			(AD9523_R1B | 0x22D)
65 
66 #define AD9523_STATUS_SIGNALS			(AD9523_R3B | 0x232)
67 #define AD9523_POWER_DOWN_CTRL			(AD9523_R1B | 0x233)
68 #define AD9523_IO_UPDATE			(AD9523_R1B | 0x234)
69 
70 #define AD9523_EEPROM_DATA_XFER_STATUS		(AD9523_R1B | 0xB00)
71 #define AD9523_EEPROM_ERROR_READBACK		(AD9523_R1B | 0xB01)
72 #define AD9523_EEPROM_CTRL1			(AD9523_R1B | 0xB02)
73 #define AD9523_EEPROM_CTRL2			(AD9523_R1B | 0xB03)
74 
75 /* AD9523_SERIAL_PORT_CONFIG */
76 
77 #define AD9523_SER_CONF_SDO_ACTIVE		(1 << 7)
78 #define AD9523_SER_CONF_SOFT_RESET		(1 << 5)
79 
80 /* AD9523_READBACK_CTRL */
81 #define AD9523_READBACK_CTRL_READ_BUFFERED	(1 << 0)
82 
83 /* AD9523_PLL1_CHARGE_PUMP_CTRL */
84 #define AD9523_PLL1_CHARGE_PUMP_CURRENT_nA(x)	(((x) / 500) & 0x7F)
85 #define AD9523_PLL1_CHARGE_PUMP_TRISTATE	(1 << 7)
86 #define AD9523_PLL1_CHARGE_PUMP_MODE_NORMAL	(3 << 8)
87 #define AD9523_PLL1_CHARGE_PUMP_MODE_PUMP_DOWN	(2 << 8)
88 #define AD9523_PLL1_CHARGE_PUMP_MODE_PUMP_UP	(1 << 8)
89 #define AD9523_PLL1_CHARGE_PUMP_MODE_TRISTATE	(0 << 8)
90 #define AD9523_PLL1_BACKLASH_PW_MIN		(0 << 10)
91 #define AD9523_PLL1_BACKLASH_PW_LOW		(1 << 10)
92 #define AD9523_PLL1_BACKLASH_PW_HIGH		(2 << 10)
93 #define AD9523_PLL1_BACKLASH_PW_MAX		(3 << 10)
94 
95 /* AD9523_PLL1_INPUT_RECEIVERS_CTRL */
96 #define AD9523_PLL1_REF_TEST_RCV_EN		(1 << 7)
97 #define AD9523_PLL1_REFB_DIFF_RCV_EN		(1 << 6)
98 #define AD9523_PLL1_REFA_DIFF_RCV_EN		(1 << 5)
99 #define AD9523_PLL1_REFB_RCV_EN			(1 << 4)
100 #define AD9523_PLL1_REFA_RCV_EN			(1 << 3)
101 #define AD9523_PLL1_REFA_REFB_PWR_CTRL_EN	(1 << 2)
102 #define AD9523_PLL1_OSC_IN_CMOS_NEG_INP_EN	(1 << 1)
103 #define AD9523_PLL1_OSC_IN_DIFF_EN		(1 << 0)
104 
105 /* AD9523_PLL1_REF_CTRL */
106 #define AD9523_PLL1_BYPASS_REF_TEST_DIV_EN	(1 << 7)
107 #define AD9523_PLL1_BYPASS_FEEDBACK_DIV_EN	(1 << 6)
108 #define AD9523_PLL1_ZERO_DELAY_MODE_INT		(1 << 5)
109 #define AD9523_PLL1_ZERO_DELAY_MODE_EXT		(0 << 5)
110 #define AD9523_PLL1_OSC_IN_PLL_FEEDBACK_EN	(1 << 4)
111 #define AD9523_PLL1_ZD_IN_CMOS_NEG_INP_EN	(1 << 3)
112 #define AD9523_PLL1_ZD_IN_DIFF_EN		(1 << 2)
113 #define AD9523_PLL1_REFB_CMOS_NEG_INP_EN	(1 << 1)
114 #define AD9523_PLL1_REFA_CMOS_NEG_INP_EN	(1 << 0)
115 
116 /* AD9523_PLL1_MISC_CTRL */
117 #define AD9523_PLL1_REFB_INDEP_DIV_CTRL_EN	(1 << 7)
118 #define AD9523_PLL1_OSC_CTRL_FAIL_VCC_BY2_EN	(1 << 6)
119 #define AD9523_PLL1_REF_MODE(x)			((x) << 2)
120 #define AD9523_PLL1_BYPASS_REFB_DIV		(1 << 1)
121 #define AD9523_PLL1_BYPASS_REFA_DIV		(1 << 0)
122 
123 /* AD9523_PLL1_LOOP_FILTER_CTRL */
124 #define AD9523_PLL1_LOOP_FILTER_RZERO(x)	((x) & 0xF)
125 
126 /* AD9523_PLL2_CHARGE_PUMP */
127 #define AD9523_PLL2_CHARGE_PUMP_CURRENT_nA(x)	((x) / 3500)
128 
129 /* AD9523_PLL2_FEEDBACK_DIVIDER_AB */
130 #define AD9523_PLL2_FB_NDIV_A_CNT(x)		(((x) & 0x3) << 6)
131 #define AD9523_PLL2_FB_NDIV_B_CNT(x)		(((x) & 0x3F) << 0)
132 #define AD9523_PLL2_FB_NDIV(a, b)		(4 * (b) + (a))
133 
134 /* AD9523_PLL2_CTRL */
135 #define AD9523_PLL2_CHARGE_PUMP_MODE_NORMAL	(3 << 0)
136 #define AD9523_PLL2_CHARGE_PUMP_MODE_PUMP_DOWN	(2 << 0)
137 #define AD9523_PLL2_CHARGE_PUMP_MODE_PUMP_UP	(1 << 0)
138 #define AD9523_PLL2_CHARGE_PUMP_MODE_TRISTATE	(0 << 0)
139 #define AD9523_PLL2_BACKLASH_PW_MIN		(0 << 2)
140 #define AD9523_PLL2_BACKLASH_PW_LOW		(1 << 2)
141 #define AD9523_PLL2_BACKLASH_PW_HIGH		(2 << 2)
142 #define AD9523_PLL2_BACKLASH_PW_MAX		(3 << 1)
143 #define AD9523_PLL2_BACKLASH_CTRL_EN		(1 << 4)
144 #define AD9523_PLL2_FREQ_DOUBLER_EN		(1 << 5)
145 #define AD9523_PLL2_LOCK_DETECT_PWR_DOWN_EN	(1 << 7)
146 
147 /* AD9523_PLL2_VCO_CTRL */
148 #define AD9523_PLL2_VCO_CALIBRATE		(1 << 1)
149 #define AD9523_PLL2_FORCE_VCO_MIDSCALE		(1 << 2)
150 #define AD9523_PLL2_FORCE_REFERENCE_VALID	(1 << 3)
151 #define AD9523_PLL2_FORCE_RELEASE_SYNC		(1 << 4)
152 
153 /* AD9523_PLL2_VCO_DIVIDER */
154 #define AD9523_PLL2_VCO_DIV_M1(x)		((((x) - 3) & 0x3) << 0)
155 #define AD9523_PLL2_VCO_DIV_M2(x)		((((x) - 3) & 0x3) << 4)
156 #define AD9523_PLL2_VCO_DIV_M1_PWR_DOWN_EN	(1 << 2)
157 #define AD9523_PLL2_VCO_DIV_M2_PWR_DOWN_EN	(1 << 6)
158 
159 /* AD9523_PLL2_LOOP_FILTER_CTRL */
160 #define AD9523_PLL2_LOOP_FILTER_CPOLE1(x)	(((x) & 0x7) << 0)
161 #define AD9523_PLL2_LOOP_FILTER_RZERO(x)	(((x) & 0x7) << 3)
162 #define AD9523_PLL2_LOOP_FILTER_RPOLE2(x)	(((x) & 0x7) << 6)
163 #define AD9523_PLL2_LOOP_FILTER_RZERO_BYPASS_EN	(1 << 8)
164 
165 /* AD9523_PLL2_R2_DIVIDER */
166 #define AD9523_PLL2_R2_DIVIDER_VAL(x)		(((x) & 0x1F) << 0)
167 
168 /* AD9523_CHANNEL_CLOCK_DIST */
169 #define AD9523_CLK_DIST_DIV_PHASE(x)		(((x) & 0x3F) << 18)
170 #define AD9523_CLK_DIST_DIV_PHASE_REV(x)	((ret >> 18) & 0x3F)
171 #define AD9523_CLK_DIST_DIV(x)			((((x) - 1) & 0x3FF) << 8)
172 #define AD9523_CLK_DIST_DIV_REV(x)		(((ret >> 8) & 0x3FF) + 1)
173 #define AD9523_CLK_DIST_INV_DIV_OUTPUT_EN	(1 << 7)
174 #define AD9523_CLK_DIST_IGNORE_SYNC_EN		(1 << 6)
175 #define AD9523_CLK_DIST_PWR_DOWN_EN		(1 << 5)
176 #define AD9523_CLK_DIST_LOW_PWR_MODE_EN		(1 << 4)
177 #define AD9523_CLK_DIST_DRIVER_MODE(x)		(((x) & 0xF) << 0)
178 
179 /* AD9523_PLL1_OUTPUT_CTRL */
180 #define AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH6_M2	(1 << 7)
181 #define AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH5_M2	(1 << 6)
182 #define AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH4_M2	(1 << 5)
183 #define AD9523_PLL1_OUTP_CTRL_CMOS_DRV_WEAK		(1 << 4)
184 #define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_1		(0 << 0)
185 #define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_2		(1 << 0)
186 #define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_4		(2 << 0)
187 #define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_8		(4 << 0)
188 #define AD9523_PLL1_OUTP_CTRL_OUTPUT_DIV_16		(8 << 0)
189 
190 /* AD9523_PLL1_OUTPUT_CHANNEL_CTRL */
191 #define AD9523_PLL1_OUTP_CH_CTRL_OUTPUT_PWR_DOWN_EN	(1 << 7)
192 #define AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH9_M2	(1 << 6)
193 #define AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH8_M2	(1 << 5)
194 #define AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH7_M2	(1 << 4)
195 #define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH3	(1 << 3)
196 #define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH2	(1 << 2)
197 #define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH1	(1 << 1)
198 #define AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH0	(1 << 0)
199 
200 /* AD9523_READBACK_0 */
201 #define AD9523_READBACK_0_STAT_PLL2_REF_CLK		(1 << 7)
202 #define AD9523_READBACK_0_STAT_PLL2_FB_CLK		(1 << 6)
203 #define AD9523_READBACK_0_STAT_VCXO			(1 << 5)
204 #define AD9523_READBACK_0_STAT_REF_TEST			(1 << 4)
205 #define AD9523_READBACK_0_STAT_REFB			(1 << 3)
206 #define AD9523_READBACK_0_STAT_REFA			(1 << 2)
207 #define AD9523_READBACK_0_STAT_PLL2_LD			(1 << 1)
208 #define AD9523_READBACK_0_STAT_PLL1_LD			(1 << 0)
209 
210 /* AD9523_READBACK_1 */
211 #define AD9523_READBACK_1_HOLDOVER_ACTIVE		(1 << 3)
212 #define AD9523_READBACK_1_AUTOMODE_SEL_REFB		(1 << 2)
213 #define AD9523_READBACK_1_VCO_CALIB_IN_PROGRESS		(1 << 0)
214 
215 /* AD9523_STATUS_SIGNALS */
216 #define AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL		(1 << 16)
217 #define AD9523_STATUS_MONITOR_01_PLL12_LOCKED		(0x302)
218 /* AD9523_POWER_DOWN_CTRL */
219 #define AD9523_POWER_DOWN_CTRL_PLL1_PWR_DOWN		(1 << 2)
220 #define AD9523_POWER_DOWN_CTRL_PLL2_PWR_DOWN		(1 << 1)
221 #define AD9523_POWER_DOWN_CTRL_DIST_PWR_DOWN		(1 << 0)
222 
223 /* AD9523_IO_UPDATE */
224 #define AD9523_IO_UPDATE_EN				(1 << 0)
225 
226 /* AD9523_EEPROM_DATA_XFER_STATUS */
227 #define AD9523_EEPROM_DATA_XFER_IN_PROGRESS		(1 << 0)
228 
229 /* AD9523_EEPROM_ERROR_READBACK */
230 #define AD9523_EEPROM_ERROR_READBACK_FAIL		(1 << 0)
231 
232 /* AD9523_EEPROM_CTRL1 */
233 #define AD9523_EEPROM_CTRL1_SOFT_EEPROM			(1 << 1)
234 #define AD9523_EEPROM_CTRL1_EEPROM_WRITE_PROT_DIS	(1 << 0)
235 
236 /* AD9523_EEPROM_CTRL2 */
237 #define AD9523_EEPROM_CTRL2_REG2EEPROM			(1 << 0)
238 
239 #define AD9523_NUM_CHAN					14
240 #define AD9523_NUM_CHAN_ALT_CLK_SRC			10
241 
242 /* Helpers to avoid excess line breaks */
243 #define AD_IFE(_pde, _a, _b) ((pdata->_pde) ? _a : _b)
244 #define AD_IF(_pde, _a) AD_IFE(_pde, _a, 0)
245 
246 enum {
247 	AD9523_STAT_PLL1_LD,
248 	AD9523_STAT_PLL2_LD,
249 	AD9523_STAT_REFA,
250 	AD9523_STAT_REFB,
251 	AD9523_STAT_REF_TEST,
252 	AD9523_STAT_VCXO,
253 	AD9523_STAT_PLL2_FB_CLK,
254 	AD9523_STAT_PLL2_REF_CLK,
255 	AD9523_SYNC,
256 	AD9523_EEPROM,
257 };
258 
259 enum {
260 	AD9523_VCO1,
261 	AD9523_VCO2,
262 	AD9523_VCXO,
263 	AD9523_NUM_CLK_SRC,
264 };
265 
266 struct ad9523_state {
267 	struct spi_device		*spi;
268 	struct ad9523_platform_data	*pdata;
269 	struct iio_chan_spec		ad9523_channels[AD9523_NUM_CHAN];
270 	struct gpio_desc		*pwrdown_gpio;
271 	struct gpio_desc		*reset_gpio;
272 	struct gpio_desc		*sync_gpio;
273 
274 	unsigned long		vcxo_freq;
275 	unsigned long		vco_freq;
276 	unsigned long		vco_out_freq[AD9523_NUM_CLK_SRC];
277 	unsigned char		vco_out_map[AD9523_NUM_CHAN_ALT_CLK_SRC];
278 
279 	/*
280 	 * Lock for accessing device registers. Some operations require
281 	 * multiple consecutive R/W operations, during which the device
282 	 * shouldn't be interrupted.  The buffers are also shared across
283 	 * all operations so need to be protected on stand alone reads and
284 	 * writes.
285 	 */
286 	struct mutex		lock;
287 
288 	/*
289 	 * DMA (thus cache coherency maintenance) may require that
290 	 * transfer buffers live in their own cache lines.
291 	 */
292 	union {
293 		__be32 d32;
294 		u8 d8[4];
295 	} data[2] __aligned(IIO_DMA_MINALIGN);
296 };
297 
298 static int ad9523_read(struct iio_dev *indio_dev, unsigned int addr)
299 {
300 	struct ad9523_state *st = iio_priv(indio_dev);
301 	int ret;
302 
303 	/* We encode the register size 1..3 bytes into the register address.
304 	 * On transfer we get the size from the register datum, and make sure
305 	 * the result is properly aligned.
306 	 */
307 
308 	struct spi_transfer t[] = {
309 		{
310 			.tx_buf = &st->data[0].d8[2],
311 			.len = 2,
312 		}, {
313 			.rx_buf = &st->data[1].d8[4 - AD9523_TRANSF_LEN(addr)],
314 			.len = AD9523_TRANSF_LEN(addr),
315 		},
316 	};
317 
318 	st->data[0].d32 = cpu_to_be32(AD9523_READ |
319 				      AD9523_CNT(AD9523_TRANSF_LEN(addr)) |
320 				      AD9523_ADDR(addr));
321 
322 	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
323 	if (ret < 0)
324 		dev_err(&indio_dev->dev, "read failed (%d)", ret);
325 	else
326 		ret = be32_to_cpu(st->data[1].d32) & (0xFFFFFF >>
327 				  (8 * (3 - AD9523_TRANSF_LEN(addr))));
328 
329 	return ret;
330 };
331 
332 static int ad9523_write(struct iio_dev *indio_dev,
333 		unsigned int addr, unsigned int val)
334 {
335 	struct ad9523_state *st = iio_priv(indio_dev);
336 	int ret;
337 	struct spi_transfer t[] = {
338 		{
339 			.tx_buf = &st->data[0].d8[2],
340 			.len = 2,
341 		}, {
342 			.tx_buf = &st->data[1].d8[4 - AD9523_TRANSF_LEN(addr)],
343 			.len = AD9523_TRANSF_LEN(addr),
344 		},
345 	};
346 
347 	st->data[0].d32 = cpu_to_be32(AD9523_WRITE |
348 				      AD9523_CNT(AD9523_TRANSF_LEN(addr)) |
349 				      AD9523_ADDR(addr));
350 	st->data[1].d32 = cpu_to_be32(val);
351 
352 	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
353 
354 	if (ret < 0)
355 		dev_err(&indio_dev->dev, "write failed (%d)", ret);
356 
357 	return ret;
358 }
359 
360 static int ad9523_io_update(struct iio_dev *indio_dev)
361 {
362 	return ad9523_write(indio_dev, AD9523_IO_UPDATE, AD9523_IO_UPDATE_EN);
363 }
364 
365 static int ad9523_vco_out_map(struct iio_dev *indio_dev,
366 			      unsigned int ch, unsigned int out)
367 {
368 	struct ad9523_state *st = iio_priv(indio_dev);
369 	int ret;
370 	unsigned int mask;
371 
372 	switch (ch) {
373 	case 0 ... 3:
374 		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CHANNEL_CTRL);
375 		if (ret < 0)
376 			break;
377 		mask = AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH0 << ch;
378 		if (out) {
379 			ret |= mask;
380 			out = 2;
381 		} else {
382 			ret &= ~mask;
383 		}
384 		ret = ad9523_write(indio_dev,
385 				   AD9523_PLL1_OUTPUT_CHANNEL_CTRL, ret);
386 		break;
387 	case 4 ... 6:
388 		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CTRL);
389 		if (ret < 0)
390 			break;
391 		mask = AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH4_M2 << (ch - 4);
392 		if (out)
393 			ret |= mask;
394 		else
395 			ret &= ~mask;
396 		ret = ad9523_write(indio_dev, AD9523_PLL1_OUTPUT_CTRL, ret);
397 		break;
398 	case 7 ... 9:
399 		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CHANNEL_CTRL);
400 		if (ret < 0)
401 			break;
402 		mask = AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH7_M2 << (ch - 7);
403 		if (out)
404 			ret |= mask;
405 		else
406 			ret &= ~mask;
407 		ret = ad9523_write(indio_dev,
408 				   AD9523_PLL1_OUTPUT_CHANNEL_CTRL, ret);
409 		break;
410 	default:
411 		return 0;
412 	}
413 
414 	st->vco_out_map[ch] = out;
415 
416 	return ret;
417 }
418 
419 static int ad9523_set_clock_provider(struct iio_dev *indio_dev,
420 			      unsigned int ch, unsigned long freq)
421 {
422 	struct ad9523_state *st = iio_priv(indio_dev);
423 	long tmp1, tmp2;
424 	bool use_alt_clk_src;
425 
426 	switch (ch) {
427 	case 0 ... 3:
428 		use_alt_clk_src = (freq == st->vco_out_freq[AD9523_VCXO]);
429 		break;
430 	case 4 ... 9:
431 		tmp1 = st->vco_out_freq[AD9523_VCO1] / freq;
432 		tmp2 = st->vco_out_freq[AD9523_VCO2] / freq;
433 		tmp1 *= freq;
434 		tmp2 *= freq;
435 		use_alt_clk_src = (abs(tmp1 - freq) > abs(tmp2 - freq));
436 		break;
437 	default:
438 		/* Ch 10..14: No action required, return success */
439 		return 0;
440 	}
441 
442 	return ad9523_vco_out_map(indio_dev, ch, use_alt_clk_src);
443 }
444 
445 static int ad9523_store_eeprom(struct iio_dev *indio_dev)
446 {
447 	int ret, tmp;
448 
449 	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL1,
450 			   AD9523_EEPROM_CTRL1_EEPROM_WRITE_PROT_DIS);
451 	if (ret < 0)
452 		return ret;
453 	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL2,
454 			   AD9523_EEPROM_CTRL2_REG2EEPROM);
455 	if (ret < 0)
456 		return ret;
457 
458 	tmp = 4;
459 	do {
460 		msleep(20);
461 		ret = ad9523_read(indio_dev,
462 				  AD9523_EEPROM_DATA_XFER_STATUS);
463 		if (ret < 0)
464 			return ret;
465 	} while ((ret & AD9523_EEPROM_DATA_XFER_IN_PROGRESS) && tmp--);
466 
467 	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL1, 0);
468 	if (ret < 0)
469 		return ret;
470 
471 	ret = ad9523_read(indio_dev, AD9523_EEPROM_ERROR_READBACK);
472 	if (ret < 0)
473 		return ret;
474 
475 	if (ret & AD9523_EEPROM_ERROR_READBACK_FAIL) {
476 		dev_err(&indio_dev->dev, "Verify EEPROM failed");
477 		ret = -EIO;
478 	}
479 
480 	return ret;
481 }
482 
483 static int ad9523_sync(struct iio_dev *indio_dev)
484 {
485 	int ret, tmp;
486 
487 	ret = ad9523_read(indio_dev, AD9523_STATUS_SIGNALS);
488 	if (ret < 0)
489 		return ret;
490 
491 	tmp = ret;
492 	tmp |= AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL;
493 
494 	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS, tmp);
495 	if (ret < 0)
496 		return ret;
497 
498 	ad9523_io_update(indio_dev);
499 	tmp &= ~AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL;
500 
501 	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS, tmp);
502 	if (ret < 0)
503 		return ret;
504 
505 	return ad9523_io_update(indio_dev);
506 }
507 
508 static ssize_t ad9523_store(struct device *dev,
509 				struct device_attribute *attr,
510 				const char *buf, size_t len)
511 {
512 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
513 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
514 	struct ad9523_state *st = iio_priv(indio_dev);
515 	bool state;
516 	int ret;
517 
518 	ret = kstrtobool(buf, &state);
519 	if (ret < 0)
520 		return ret;
521 
522 	if (!state)
523 		return len;
524 
525 	mutex_lock(&st->lock);
526 	switch ((u32)this_attr->address) {
527 	case AD9523_SYNC:
528 		ret = ad9523_sync(indio_dev);
529 		break;
530 	case AD9523_EEPROM:
531 		ret = ad9523_store_eeprom(indio_dev);
532 		break;
533 	default:
534 		ret = -ENODEV;
535 	}
536 	mutex_unlock(&st->lock);
537 
538 	return ret ? ret : len;
539 }
540 
541 static ssize_t ad9523_show(struct device *dev,
542 			struct device_attribute *attr,
543 			char *buf)
544 {
545 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
546 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
547 	struct ad9523_state *st = iio_priv(indio_dev);
548 	int ret;
549 
550 	mutex_lock(&st->lock);
551 	ret = ad9523_read(indio_dev, AD9523_READBACK_0);
552 	if (ret >= 0) {
553 		ret = sysfs_emit(buf, "%d\n", !!(ret & (1 <<
554 			(u32)this_attr->address)));
555 	}
556 	mutex_unlock(&st->lock);
557 
558 	return ret;
559 }
560 
561 static IIO_DEVICE_ATTR(pll1_locked, S_IRUGO,
562 			ad9523_show,
563 			NULL,
564 			AD9523_STAT_PLL1_LD);
565 
566 static IIO_DEVICE_ATTR(pll2_locked, S_IRUGO,
567 			ad9523_show,
568 			NULL,
569 			AD9523_STAT_PLL2_LD);
570 
571 static IIO_DEVICE_ATTR(pll1_reference_clk_a_present, S_IRUGO,
572 			ad9523_show,
573 			NULL,
574 			AD9523_STAT_REFA);
575 
576 static IIO_DEVICE_ATTR(pll1_reference_clk_b_present, S_IRUGO,
577 			ad9523_show,
578 			NULL,
579 			AD9523_STAT_REFB);
580 
581 static IIO_DEVICE_ATTR(pll1_reference_clk_test_present, S_IRUGO,
582 			ad9523_show,
583 			NULL,
584 			AD9523_STAT_REF_TEST);
585 
586 static IIO_DEVICE_ATTR(vcxo_clk_present, S_IRUGO,
587 			ad9523_show,
588 			NULL,
589 			AD9523_STAT_VCXO);
590 
591 static IIO_DEVICE_ATTR(pll2_feedback_clk_present, S_IRUGO,
592 			ad9523_show,
593 			NULL,
594 			AD9523_STAT_PLL2_FB_CLK);
595 
596 static IIO_DEVICE_ATTR(pll2_reference_clk_present, S_IRUGO,
597 			ad9523_show,
598 			NULL,
599 			AD9523_STAT_PLL2_REF_CLK);
600 
601 static IIO_DEVICE_ATTR(sync_dividers, S_IWUSR,
602 			NULL,
603 			ad9523_store,
604 			AD9523_SYNC);
605 
606 static IIO_DEVICE_ATTR(store_eeprom, S_IWUSR,
607 			NULL,
608 			ad9523_store,
609 			AD9523_EEPROM);
610 
611 static struct attribute *ad9523_attributes[] = {
612 	&iio_dev_attr_sync_dividers.dev_attr.attr,
613 	&iio_dev_attr_store_eeprom.dev_attr.attr,
614 	&iio_dev_attr_pll2_feedback_clk_present.dev_attr.attr,
615 	&iio_dev_attr_pll2_reference_clk_present.dev_attr.attr,
616 	&iio_dev_attr_pll1_reference_clk_a_present.dev_attr.attr,
617 	&iio_dev_attr_pll1_reference_clk_b_present.dev_attr.attr,
618 	&iio_dev_attr_pll1_reference_clk_test_present.dev_attr.attr,
619 	&iio_dev_attr_vcxo_clk_present.dev_attr.attr,
620 	&iio_dev_attr_pll1_locked.dev_attr.attr,
621 	&iio_dev_attr_pll2_locked.dev_attr.attr,
622 	NULL,
623 };
624 
625 static const struct attribute_group ad9523_attribute_group = {
626 	.attrs = ad9523_attributes,
627 };
628 
629 static int ad9523_read_raw(struct iio_dev *indio_dev,
630 			   struct iio_chan_spec const *chan,
631 			   int *val,
632 			   int *val2,
633 			   long m)
634 {
635 	struct ad9523_state *st = iio_priv(indio_dev);
636 	unsigned int code;
637 	int ret;
638 
639 	mutex_lock(&st->lock);
640 	ret = ad9523_read(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel));
641 	mutex_unlock(&st->lock);
642 
643 	if (ret < 0)
644 		return ret;
645 
646 	switch (m) {
647 	case IIO_CHAN_INFO_RAW:
648 		*val = !(ret & AD9523_CLK_DIST_PWR_DOWN_EN);
649 		return IIO_VAL_INT;
650 	case IIO_CHAN_INFO_FREQUENCY:
651 		*val = st->vco_out_freq[st->vco_out_map[chan->channel]] /
652 			AD9523_CLK_DIST_DIV_REV(ret);
653 		return IIO_VAL_INT;
654 	case IIO_CHAN_INFO_PHASE:
655 		code = (AD9523_CLK_DIST_DIV_PHASE_REV(ret) * 3141592) /
656 			AD9523_CLK_DIST_DIV_REV(ret);
657 		*val = code / 1000000;
658 		*val2 = code % 1000000;
659 		return IIO_VAL_INT_PLUS_MICRO;
660 	default:
661 		return -EINVAL;
662 	}
663 };
664 
665 static int ad9523_write_raw(struct iio_dev *indio_dev,
666 			    struct iio_chan_spec const *chan,
667 			    int val,
668 			    int val2,
669 			    long mask)
670 {
671 	struct ad9523_state *st = iio_priv(indio_dev);
672 	unsigned int reg;
673 	int ret, tmp, code;
674 
675 	mutex_lock(&st->lock);
676 	ret = ad9523_read(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel));
677 	if (ret < 0)
678 		goto out;
679 
680 	reg = ret;
681 
682 	switch (mask) {
683 	case IIO_CHAN_INFO_RAW:
684 		if (val)
685 			reg &= ~AD9523_CLK_DIST_PWR_DOWN_EN;
686 		else
687 			reg |= AD9523_CLK_DIST_PWR_DOWN_EN;
688 		break;
689 	case IIO_CHAN_INFO_FREQUENCY:
690 		if (val <= 0) {
691 			ret = -EINVAL;
692 			goto out;
693 		}
694 		ret = ad9523_set_clock_provider(indio_dev, chan->channel, val);
695 		if (ret < 0)
696 			goto out;
697 		tmp = st->vco_out_freq[st->vco_out_map[chan->channel]] / val;
698 		tmp = clamp(tmp, 1, 1024);
699 		reg &= ~(0x3FF << 8);
700 		reg |= AD9523_CLK_DIST_DIV(tmp);
701 		break;
702 	case IIO_CHAN_INFO_PHASE:
703 		code = val * 1000000 + val2 % 1000000;
704 		tmp = (code * AD9523_CLK_DIST_DIV_REV(ret)) / 3141592;
705 		tmp = clamp(tmp, 0, 63);
706 		reg &= ~AD9523_CLK_DIST_DIV_PHASE(~0);
707 		reg |= AD9523_CLK_DIST_DIV_PHASE(tmp);
708 		break;
709 	default:
710 		ret = -EINVAL;
711 		goto out;
712 	}
713 
714 	ret = ad9523_write(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel),
715 			   reg);
716 	if (ret < 0)
717 		goto out;
718 
719 	ad9523_io_update(indio_dev);
720 out:
721 	mutex_unlock(&st->lock);
722 	return ret;
723 }
724 
725 static int ad9523_reg_access(struct iio_dev *indio_dev,
726 			      unsigned int reg, unsigned int writeval,
727 			      unsigned int *readval)
728 {
729 	struct ad9523_state *st = iio_priv(indio_dev);
730 	int ret;
731 
732 	mutex_lock(&st->lock);
733 	if (readval == NULL) {
734 		ret = ad9523_write(indio_dev, reg | AD9523_R1B, writeval);
735 		ad9523_io_update(indio_dev);
736 	} else {
737 		ret = ad9523_read(indio_dev, reg | AD9523_R1B);
738 		if (ret < 0)
739 			goto out_unlock;
740 		*readval = ret;
741 		ret = 0;
742 	}
743 
744 out_unlock:
745 	mutex_unlock(&st->lock);
746 
747 	return ret;
748 }
749 
750 static const struct iio_info ad9523_info = {
751 	.read_raw = &ad9523_read_raw,
752 	.write_raw = &ad9523_write_raw,
753 	.debugfs_reg_access = &ad9523_reg_access,
754 	.attrs = &ad9523_attribute_group,
755 };
756 
757 static int ad9523_setup(struct iio_dev *indio_dev)
758 {
759 	struct ad9523_state *st = iio_priv(indio_dev);
760 	struct ad9523_platform_data *pdata = st->pdata;
761 	struct ad9523_channel_spec *chan;
762 	unsigned long active_mask = 0;
763 	int ret, i;
764 
765 	ret = ad9523_write(indio_dev, AD9523_SERIAL_PORT_CONFIG,
766 			   AD9523_SER_CONF_SOFT_RESET |
767 			  (st->spi->mode & SPI_3WIRE ? 0 :
768 			  AD9523_SER_CONF_SDO_ACTIVE));
769 	if (ret < 0)
770 		return ret;
771 
772 	ret = ad9523_write(indio_dev, AD9523_READBACK_CTRL,
773 			  AD9523_READBACK_CTRL_READ_BUFFERED);
774 	if (ret < 0)
775 		return ret;
776 
777 	ret = ad9523_io_update(indio_dev);
778 	if (ret < 0)
779 		return ret;
780 
781 	/*
782 	 * PLL1 Setup
783 	 */
784 	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_A_DIVIDER,
785 		pdata->refa_r_div);
786 	if (ret < 0)
787 		return ret;
788 
789 	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_B_DIVIDER,
790 		pdata->refb_r_div);
791 	if (ret < 0)
792 		return ret;
793 
794 	ret = ad9523_write(indio_dev, AD9523_PLL1_FEEDBACK_DIVIDER,
795 		pdata->pll1_feedback_div);
796 	if (ret < 0)
797 		return ret;
798 
799 	ret = ad9523_write(indio_dev, AD9523_PLL1_CHARGE_PUMP_CTRL,
800 		AD9523_PLL1_CHARGE_PUMP_CURRENT_nA(pdata->
801 			pll1_charge_pump_current_nA) |
802 		AD9523_PLL1_CHARGE_PUMP_MODE_NORMAL |
803 		AD9523_PLL1_BACKLASH_PW_MIN);
804 	if (ret < 0)
805 		return ret;
806 
807 	ret = ad9523_write(indio_dev, AD9523_PLL1_INPUT_RECEIVERS_CTRL,
808 		AD_IF(refa_diff_rcv_en, AD9523_PLL1_REFA_RCV_EN) |
809 		AD_IF(refb_diff_rcv_en, AD9523_PLL1_REFB_RCV_EN) |
810 		AD_IF(osc_in_diff_en, AD9523_PLL1_OSC_IN_DIFF_EN) |
811 		AD_IF(osc_in_cmos_neg_inp_en,
812 		      AD9523_PLL1_OSC_IN_CMOS_NEG_INP_EN) |
813 		AD_IF(refa_diff_rcv_en, AD9523_PLL1_REFA_DIFF_RCV_EN) |
814 		AD_IF(refb_diff_rcv_en, AD9523_PLL1_REFB_DIFF_RCV_EN));
815 	if (ret < 0)
816 		return ret;
817 
818 	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_CTRL,
819 		AD_IF(zd_in_diff_en, AD9523_PLL1_ZD_IN_DIFF_EN) |
820 		AD_IF(zd_in_cmos_neg_inp_en,
821 		      AD9523_PLL1_ZD_IN_CMOS_NEG_INP_EN) |
822 		AD_IF(zero_delay_mode_internal_en,
823 		      AD9523_PLL1_ZERO_DELAY_MODE_INT) |
824 		AD_IF(osc_in_feedback_en, AD9523_PLL1_OSC_IN_PLL_FEEDBACK_EN) |
825 		AD_IF(refa_cmos_neg_inp_en, AD9523_PLL1_REFA_CMOS_NEG_INP_EN) |
826 		AD_IF(refb_cmos_neg_inp_en, AD9523_PLL1_REFB_CMOS_NEG_INP_EN));
827 	if (ret < 0)
828 		return ret;
829 
830 	ret = ad9523_write(indio_dev, AD9523_PLL1_MISC_CTRL,
831 		AD9523_PLL1_REFB_INDEP_DIV_CTRL_EN |
832 		AD9523_PLL1_REF_MODE(pdata->ref_mode));
833 	if (ret < 0)
834 		return ret;
835 
836 	ret = ad9523_write(indio_dev, AD9523_PLL1_LOOP_FILTER_CTRL,
837 		AD9523_PLL1_LOOP_FILTER_RZERO(pdata->pll1_loop_filter_rzero));
838 	if (ret < 0)
839 		return ret;
840 	/*
841 	 * PLL2 Setup
842 	 */
843 
844 	ret = ad9523_write(indio_dev, AD9523_PLL2_CHARGE_PUMP,
845 		AD9523_PLL2_CHARGE_PUMP_CURRENT_nA(pdata->
846 			pll2_charge_pump_current_nA));
847 	if (ret < 0)
848 		return ret;
849 
850 	ret = ad9523_write(indio_dev, AD9523_PLL2_FEEDBACK_DIVIDER_AB,
851 		AD9523_PLL2_FB_NDIV_A_CNT(pdata->pll2_ndiv_a_cnt) |
852 		AD9523_PLL2_FB_NDIV_B_CNT(pdata->pll2_ndiv_b_cnt));
853 	if (ret < 0)
854 		return ret;
855 
856 	ret = ad9523_write(indio_dev, AD9523_PLL2_CTRL,
857 		AD9523_PLL2_CHARGE_PUMP_MODE_NORMAL |
858 		AD9523_PLL2_BACKLASH_CTRL_EN |
859 		AD_IF(pll2_freq_doubler_en, AD9523_PLL2_FREQ_DOUBLER_EN));
860 	if (ret < 0)
861 		return ret;
862 
863 	st->vco_freq = div_u64((unsigned long long)pdata->vcxo_freq *
864 			       (pdata->pll2_freq_doubler_en ? 2 : 1) *
865 			       AD9523_PLL2_FB_NDIV(pdata->pll2_ndiv_a_cnt,
866 						   pdata->pll2_ndiv_b_cnt),
867 			       pdata->pll2_r2_div);
868 
869 	ret = ad9523_write(indio_dev, AD9523_PLL2_VCO_CTRL,
870 		AD9523_PLL2_VCO_CALIBRATE);
871 	if (ret < 0)
872 		return ret;
873 
874 	ret = ad9523_write(indio_dev, AD9523_PLL2_VCO_DIVIDER,
875 		AD9523_PLL2_VCO_DIV_M1(pdata->pll2_vco_div_m1) |
876 		AD9523_PLL2_VCO_DIV_M2(pdata->pll2_vco_div_m2) |
877 		AD_IFE(pll2_vco_div_m1, 0,
878 		       AD9523_PLL2_VCO_DIV_M1_PWR_DOWN_EN) |
879 		AD_IFE(pll2_vco_div_m2, 0,
880 		       AD9523_PLL2_VCO_DIV_M2_PWR_DOWN_EN));
881 	if (ret < 0)
882 		return ret;
883 
884 	if (pdata->pll2_vco_div_m1)
885 		st->vco_out_freq[AD9523_VCO1] =
886 			st->vco_freq / pdata->pll2_vco_div_m1;
887 
888 	if (pdata->pll2_vco_div_m2)
889 		st->vco_out_freq[AD9523_VCO2] =
890 			st->vco_freq / pdata->pll2_vco_div_m2;
891 
892 	st->vco_out_freq[AD9523_VCXO] = pdata->vcxo_freq;
893 
894 	ret = ad9523_write(indio_dev, AD9523_PLL2_R2_DIVIDER,
895 		AD9523_PLL2_R2_DIVIDER_VAL(pdata->pll2_r2_div));
896 	if (ret < 0)
897 		return ret;
898 
899 	ret = ad9523_write(indio_dev, AD9523_PLL2_LOOP_FILTER_CTRL,
900 		AD9523_PLL2_LOOP_FILTER_CPOLE1(pdata->cpole1) |
901 		AD9523_PLL2_LOOP_FILTER_RZERO(pdata->rzero) |
902 		AD9523_PLL2_LOOP_FILTER_RPOLE2(pdata->rpole2) |
903 		AD_IF(rzero_bypass_en,
904 		      AD9523_PLL2_LOOP_FILTER_RZERO_BYPASS_EN));
905 	if (ret < 0)
906 		return ret;
907 
908 	for (i = 0; i < pdata->num_channels; i++) {
909 		chan = &pdata->channels[i];
910 		if (chan->channel_num < AD9523_NUM_CHAN) {
911 			__set_bit(chan->channel_num, &active_mask);
912 			ret = ad9523_write(indio_dev,
913 				AD9523_CHANNEL_CLOCK_DIST(chan->channel_num),
914 				AD9523_CLK_DIST_DRIVER_MODE(chan->driver_mode) |
915 				AD9523_CLK_DIST_DIV(chan->channel_divider) |
916 				AD9523_CLK_DIST_DIV_PHASE(chan->divider_phase) |
917 				(chan->sync_ignore_en ?
918 					AD9523_CLK_DIST_IGNORE_SYNC_EN : 0) |
919 				(chan->divider_output_invert_en ?
920 					AD9523_CLK_DIST_INV_DIV_OUTPUT_EN : 0) |
921 				(chan->low_power_mode_en ?
922 					AD9523_CLK_DIST_LOW_PWR_MODE_EN : 0) |
923 				(chan->output_dis ?
924 					AD9523_CLK_DIST_PWR_DOWN_EN : 0));
925 			if (ret < 0)
926 				return ret;
927 
928 			ret = ad9523_vco_out_map(indio_dev, chan->channel_num,
929 					   chan->use_alt_clock_src);
930 			if (ret < 0)
931 				return ret;
932 
933 			st->ad9523_channels[i].type = IIO_ALTVOLTAGE;
934 			st->ad9523_channels[i].output = 1;
935 			st->ad9523_channels[i].indexed = 1;
936 			st->ad9523_channels[i].channel = chan->channel_num;
937 			st->ad9523_channels[i].extend_name =
938 				chan->extended_name;
939 			st->ad9523_channels[i].info_mask_separate =
940 				BIT(IIO_CHAN_INFO_RAW) |
941 				BIT(IIO_CHAN_INFO_PHASE) |
942 				BIT(IIO_CHAN_INFO_FREQUENCY);
943 		}
944 	}
945 
946 	for_each_clear_bit(i, &active_mask, AD9523_NUM_CHAN) {
947 		ret = ad9523_write(indio_dev,
948 			     AD9523_CHANNEL_CLOCK_DIST(i),
949 			     AD9523_CLK_DIST_DRIVER_MODE(TRISTATE) |
950 			     AD9523_CLK_DIST_PWR_DOWN_EN);
951 		if (ret < 0)
952 			return ret;
953 	}
954 
955 	ret = ad9523_write(indio_dev, AD9523_POWER_DOWN_CTRL, 0);
956 	if (ret < 0)
957 		return ret;
958 
959 	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS,
960 			   AD9523_STATUS_MONITOR_01_PLL12_LOCKED);
961 	if (ret < 0)
962 		return ret;
963 
964 	ret = ad9523_io_update(indio_dev);
965 	if (ret < 0)
966 		return ret;
967 
968 	return 0;
969 }
970 
971 static int ad9523_probe(struct spi_device *spi)
972 {
973 	struct ad9523_platform_data *pdata = spi->dev.platform_data;
974 	struct iio_dev *indio_dev;
975 	struct ad9523_state *st;
976 	int ret;
977 
978 	if (!pdata) {
979 		dev_err(&spi->dev, "no platform data?\n");
980 		return -EINVAL;
981 	}
982 
983 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
984 	if (indio_dev == NULL)
985 		return -ENOMEM;
986 
987 	st = iio_priv(indio_dev);
988 
989 	mutex_init(&st->lock);
990 
991 	ret = devm_regulator_get_enable(&spi->dev, "vcc");
992 	if (ret)
993 		return ret;
994 
995 	st->pwrdown_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown",
996 		GPIOD_OUT_HIGH);
997 	if (IS_ERR(st->pwrdown_gpio))
998 		return PTR_ERR(st->pwrdown_gpio);
999 
1000 	st->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset",
1001 		GPIOD_OUT_LOW);
1002 	if (IS_ERR(st->reset_gpio))
1003 		return PTR_ERR(st->reset_gpio);
1004 
1005 	if (st->reset_gpio) {
1006 		udelay(1);
1007 		gpiod_direction_output(st->reset_gpio, 1);
1008 	}
1009 
1010 	st->sync_gpio = devm_gpiod_get_optional(&spi->dev, "sync",
1011 		GPIOD_OUT_HIGH);
1012 	if (IS_ERR(st->sync_gpio))
1013 		return PTR_ERR(st->sync_gpio);
1014 
1015 	spi_set_drvdata(spi, indio_dev);
1016 	st->spi = spi;
1017 	st->pdata = pdata;
1018 
1019 	indio_dev->name = (pdata->name[0] != 0) ? pdata->name :
1020 			  spi_get_device_id(spi)->name;
1021 	indio_dev->info = &ad9523_info;
1022 	indio_dev->modes = INDIO_DIRECT_MODE;
1023 	indio_dev->channels = st->ad9523_channels;
1024 	indio_dev->num_channels = pdata->num_channels;
1025 
1026 	ret = ad9523_setup(indio_dev);
1027 	if (ret < 0)
1028 		return ret;
1029 
1030 	return devm_iio_device_register(&spi->dev, indio_dev);
1031 }
1032 
1033 static const struct spi_device_id ad9523_id[] = {
1034 	{"ad9523-1", 9523},
1035 	{}
1036 };
1037 MODULE_DEVICE_TABLE(spi, ad9523_id);
1038 
1039 static struct spi_driver ad9523_driver = {
1040 	.driver = {
1041 		.name	= "ad9523",
1042 	},
1043 	.probe		= ad9523_probe,
1044 	.id_table	= ad9523_id,
1045 };
1046 module_spi_driver(ad9523_driver);
1047 
1048 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1049 MODULE_DESCRIPTION("Analog Devices AD9523 CLOCKDIST/PLL");
1050 MODULE_LICENSE("GPL v2");
1051