xref: /openbmc/linux/drivers/iio/frequency/ad9523.c (revision f97769fd)
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 regulator		*reg;
269 	struct ad9523_platform_data	*pdata;
270 	struct iio_chan_spec		ad9523_channels[AD9523_NUM_CHAN];
271 	struct gpio_desc		*pwrdown_gpio;
272 	struct gpio_desc		*reset_gpio;
273 	struct gpio_desc		*sync_gpio;
274 
275 	unsigned long		vcxo_freq;
276 	unsigned long		vco_freq;
277 	unsigned long		vco_out_freq[AD9523_NUM_CLK_SRC];
278 	unsigned char		vco_out_map[AD9523_NUM_CHAN_ALT_CLK_SRC];
279 
280 	/*
281 	 * Lock for accessing device registers. Some operations require
282 	 * multiple consecutive R/W operations, during which the device
283 	 * shouldn't be interrupted.  The buffers are also shared across
284 	 * all operations so need to be protected on stand alone reads and
285 	 * writes.
286 	 */
287 	struct mutex		lock;
288 
289 	/*
290 	 * DMA (thus cache coherency maintenance) requires the
291 	 * transfer buffers to live in their own cache lines.
292 	 */
293 	union {
294 		__be32 d32;
295 		u8 d8[4];
296 	} data[2] ____cacheline_aligned;
297 };
298 
299 static int ad9523_read(struct iio_dev *indio_dev, unsigned int addr)
300 {
301 	struct ad9523_state *st = iio_priv(indio_dev);
302 	int ret;
303 
304 	/* We encode the register size 1..3 bytes into the register address.
305 	 * On transfer we get the size from the register datum, and make sure
306 	 * the result is properly aligned.
307 	 */
308 
309 	struct spi_transfer t[] = {
310 		{
311 			.tx_buf = &st->data[0].d8[2],
312 			.len = 2,
313 		}, {
314 			.rx_buf = &st->data[1].d8[4 - AD9523_TRANSF_LEN(addr)],
315 			.len = AD9523_TRANSF_LEN(addr),
316 		},
317 	};
318 
319 	st->data[0].d32 = cpu_to_be32(AD9523_READ |
320 				      AD9523_CNT(AD9523_TRANSF_LEN(addr)) |
321 				      AD9523_ADDR(addr));
322 
323 	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
324 	if (ret < 0)
325 		dev_err(&indio_dev->dev, "read failed (%d)", ret);
326 	else
327 		ret = be32_to_cpu(st->data[1].d32) & (0xFFFFFF >>
328 				  (8 * (3 - AD9523_TRANSF_LEN(addr))));
329 
330 	return ret;
331 };
332 
333 static int ad9523_write(struct iio_dev *indio_dev,
334 		unsigned int addr, unsigned int val)
335 {
336 	struct ad9523_state *st = iio_priv(indio_dev);
337 	int ret;
338 	struct spi_transfer t[] = {
339 		{
340 			.tx_buf = &st->data[0].d8[2],
341 			.len = 2,
342 		}, {
343 			.tx_buf = &st->data[1].d8[4 - AD9523_TRANSF_LEN(addr)],
344 			.len = AD9523_TRANSF_LEN(addr),
345 		},
346 	};
347 
348 	st->data[0].d32 = cpu_to_be32(AD9523_WRITE |
349 				      AD9523_CNT(AD9523_TRANSF_LEN(addr)) |
350 				      AD9523_ADDR(addr));
351 	st->data[1].d32 = cpu_to_be32(val);
352 
353 	ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
354 
355 	if (ret < 0)
356 		dev_err(&indio_dev->dev, "write failed (%d)", ret);
357 
358 	return ret;
359 }
360 
361 static int ad9523_io_update(struct iio_dev *indio_dev)
362 {
363 	return ad9523_write(indio_dev, AD9523_IO_UPDATE, AD9523_IO_UPDATE_EN);
364 }
365 
366 static int ad9523_vco_out_map(struct iio_dev *indio_dev,
367 			      unsigned int ch, unsigned int out)
368 {
369 	struct ad9523_state *st = iio_priv(indio_dev);
370 	int ret;
371 	unsigned int mask;
372 
373 	switch (ch) {
374 	case 0 ... 3:
375 		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CHANNEL_CTRL);
376 		if (ret < 0)
377 			break;
378 		mask = AD9523_PLL1_OUTP_CH_CTRL_VCXO_SRC_SEL_CH0 << ch;
379 		if (out) {
380 			ret |= mask;
381 			out = 2;
382 		} else {
383 			ret &= ~mask;
384 		}
385 		ret = ad9523_write(indio_dev,
386 				   AD9523_PLL1_OUTPUT_CHANNEL_CTRL, ret);
387 		break;
388 	case 4 ... 6:
389 		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CTRL);
390 		if (ret < 0)
391 			break;
392 		mask = AD9523_PLL1_OUTP_CTRL_VCO_DIV_SEL_CH4_M2 << (ch - 4);
393 		if (out)
394 			ret |= mask;
395 		else
396 			ret &= ~mask;
397 		ret = ad9523_write(indio_dev, AD9523_PLL1_OUTPUT_CTRL, ret);
398 		break;
399 	case 7 ... 9:
400 		ret = ad9523_read(indio_dev, AD9523_PLL1_OUTPUT_CHANNEL_CTRL);
401 		if (ret < 0)
402 			break;
403 		mask = AD9523_PLL1_OUTP_CH_CTRL_VCO_DIV_SEL_CH7_M2 << (ch - 7);
404 		if (out)
405 			ret |= mask;
406 		else
407 			ret &= ~mask;
408 		ret = ad9523_write(indio_dev,
409 				   AD9523_PLL1_OUTPUT_CHANNEL_CTRL, ret);
410 		break;
411 	default:
412 		return 0;
413 	}
414 
415 	st->vco_out_map[ch] = out;
416 
417 	return ret;
418 }
419 
420 static int ad9523_set_clock_provider(struct iio_dev *indio_dev,
421 			      unsigned int ch, unsigned long freq)
422 {
423 	struct ad9523_state *st = iio_priv(indio_dev);
424 	long tmp1, tmp2;
425 	bool use_alt_clk_src;
426 
427 	switch (ch) {
428 	case 0 ... 3:
429 		use_alt_clk_src = (freq == st->vco_out_freq[AD9523_VCXO]);
430 		break;
431 	case 4 ... 9:
432 		tmp1 = st->vco_out_freq[AD9523_VCO1] / freq;
433 		tmp2 = st->vco_out_freq[AD9523_VCO2] / freq;
434 		tmp1 *= freq;
435 		tmp2 *= freq;
436 		use_alt_clk_src = (abs(tmp1 - freq) > abs(tmp2 - freq));
437 		break;
438 	default:
439 		/* Ch 10..14: No action required, return success */
440 		return 0;
441 	}
442 
443 	return ad9523_vco_out_map(indio_dev, ch, use_alt_clk_src);
444 }
445 
446 static int ad9523_store_eeprom(struct iio_dev *indio_dev)
447 {
448 	int ret, tmp;
449 
450 	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL1,
451 			   AD9523_EEPROM_CTRL1_EEPROM_WRITE_PROT_DIS);
452 	if (ret < 0)
453 		return ret;
454 	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL2,
455 			   AD9523_EEPROM_CTRL2_REG2EEPROM);
456 	if (ret < 0)
457 		return ret;
458 
459 	tmp = 4;
460 	do {
461 		msleep(20);
462 		ret = ad9523_read(indio_dev,
463 				  AD9523_EEPROM_DATA_XFER_STATUS);
464 		if (ret < 0)
465 			return ret;
466 	} while ((ret & AD9523_EEPROM_DATA_XFER_IN_PROGRESS) && tmp--);
467 
468 	ret = ad9523_write(indio_dev, AD9523_EEPROM_CTRL1, 0);
469 	if (ret < 0)
470 		return ret;
471 
472 	ret = ad9523_read(indio_dev, AD9523_EEPROM_ERROR_READBACK);
473 	if (ret < 0)
474 		return ret;
475 
476 	if (ret & AD9523_EEPROM_ERROR_READBACK_FAIL) {
477 		dev_err(&indio_dev->dev, "Verify EEPROM failed");
478 		ret = -EIO;
479 	}
480 
481 	return ret;
482 }
483 
484 static int ad9523_sync(struct iio_dev *indio_dev)
485 {
486 	int ret, tmp;
487 
488 	ret = ad9523_read(indio_dev, AD9523_STATUS_SIGNALS);
489 	if (ret < 0)
490 		return ret;
491 
492 	tmp = ret;
493 	tmp |= AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL;
494 
495 	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS, tmp);
496 	if (ret < 0)
497 		return ret;
498 
499 	ad9523_io_update(indio_dev);
500 	tmp &= ~AD9523_STATUS_SIGNALS_SYNC_MAN_CTRL;
501 
502 	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS, tmp);
503 	if (ret < 0)
504 		return ret;
505 
506 	return ad9523_io_update(indio_dev);
507 }
508 
509 static ssize_t ad9523_store(struct device *dev,
510 				struct device_attribute *attr,
511 				const char *buf, size_t len)
512 {
513 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
514 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
515 	struct ad9523_state *st = iio_priv(indio_dev);
516 	bool state;
517 	int ret;
518 
519 	ret = strtobool(buf, &state);
520 	if (ret < 0)
521 		return ret;
522 
523 	if (!state)
524 		return len;
525 
526 	mutex_lock(&st->lock);
527 	switch ((u32)this_attr->address) {
528 	case AD9523_SYNC:
529 		ret = ad9523_sync(indio_dev);
530 		break;
531 	case AD9523_EEPROM:
532 		ret = ad9523_store_eeprom(indio_dev);
533 		break;
534 	default:
535 		ret = -ENODEV;
536 	}
537 	mutex_unlock(&st->lock);
538 
539 	return ret ? ret : len;
540 }
541 
542 static ssize_t ad9523_show(struct device *dev,
543 			struct device_attribute *attr,
544 			char *buf)
545 {
546 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
547 	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
548 	struct ad9523_state *st = iio_priv(indio_dev);
549 	int ret;
550 
551 	mutex_lock(&st->lock);
552 	ret = ad9523_read(indio_dev, AD9523_READBACK_0);
553 	if (ret >= 0) {
554 		ret = sprintf(buf, "%d\n", !!(ret & (1 <<
555 			(u32)this_attr->address)));
556 	}
557 	mutex_unlock(&st->lock);
558 
559 	return ret;
560 }
561 
562 static IIO_DEVICE_ATTR(pll1_locked, S_IRUGO,
563 			ad9523_show,
564 			NULL,
565 			AD9523_STAT_PLL1_LD);
566 
567 static IIO_DEVICE_ATTR(pll2_locked, S_IRUGO,
568 			ad9523_show,
569 			NULL,
570 			AD9523_STAT_PLL2_LD);
571 
572 static IIO_DEVICE_ATTR(pll1_reference_clk_a_present, S_IRUGO,
573 			ad9523_show,
574 			NULL,
575 			AD9523_STAT_REFA);
576 
577 static IIO_DEVICE_ATTR(pll1_reference_clk_b_present, S_IRUGO,
578 			ad9523_show,
579 			NULL,
580 			AD9523_STAT_REFB);
581 
582 static IIO_DEVICE_ATTR(pll1_reference_clk_test_present, S_IRUGO,
583 			ad9523_show,
584 			NULL,
585 			AD9523_STAT_REF_TEST);
586 
587 static IIO_DEVICE_ATTR(vcxo_clk_present, S_IRUGO,
588 			ad9523_show,
589 			NULL,
590 			AD9523_STAT_VCXO);
591 
592 static IIO_DEVICE_ATTR(pll2_feedback_clk_present, S_IRUGO,
593 			ad9523_show,
594 			NULL,
595 			AD9523_STAT_PLL2_FB_CLK);
596 
597 static IIO_DEVICE_ATTR(pll2_reference_clk_present, S_IRUGO,
598 			ad9523_show,
599 			NULL,
600 			AD9523_STAT_PLL2_REF_CLK);
601 
602 static IIO_DEVICE_ATTR(sync_dividers, S_IWUSR,
603 			NULL,
604 			ad9523_store,
605 			AD9523_SYNC);
606 
607 static IIO_DEVICE_ATTR(store_eeprom, S_IWUSR,
608 			NULL,
609 			ad9523_store,
610 			AD9523_EEPROM);
611 
612 static struct attribute *ad9523_attributes[] = {
613 	&iio_dev_attr_sync_dividers.dev_attr.attr,
614 	&iio_dev_attr_store_eeprom.dev_attr.attr,
615 	&iio_dev_attr_pll2_feedback_clk_present.dev_attr.attr,
616 	&iio_dev_attr_pll2_reference_clk_present.dev_attr.attr,
617 	&iio_dev_attr_pll1_reference_clk_a_present.dev_attr.attr,
618 	&iio_dev_attr_pll1_reference_clk_b_present.dev_attr.attr,
619 	&iio_dev_attr_pll1_reference_clk_test_present.dev_attr.attr,
620 	&iio_dev_attr_vcxo_clk_present.dev_attr.attr,
621 	&iio_dev_attr_pll1_locked.dev_attr.attr,
622 	&iio_dev_attr_pll2_locked.dev_attr.attr,
623 	NULL,
624 };
625 
626 static const struct attribute_group ad9523_attribute_group = {
627 	.attrs = ad9523_attributes,
628 };
629 
630 static int ad9523_read_raw(struct iio_dev *indio_dev,
631 			   struct iio_chan_spec const *chan,
632 			   int *val,
633 			   int *val2,
634 			   long m)
635 {
636 	struct ad9523_state *st = iio_priv(indio_dev);
637 	unsigned int code;
638 	int ret;
639 
640 	mutex_lock(&st->lock);
641 	ret = ad9523_read(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel));
642 	mutex_unlock(&st->lock);
643 
644 	if (ret < 0)
645 		return ret;
646 
647 	switch (m) {
648 	case IIO_CHAN_INFO_RAW:
649 		*val = !(ret & AD9523_CLK_DIST_PWR_DOWN_EN);
650 		return IIO_VAL_INT;
651 	case IIO_CHAN_INFO_FREQUENCY:
652 		*val = st->vco_out_freq[st->vco_out_map[chan->channel]] /
653 			AD9523_CLK_DIST_DIV_REV(ret);
654 		return IIO_VAL_INT;
655 	case IIO_CHAN_INFO_PHASE:
656 		code = (AD9523_CLK_DIST_DIV_PHASE_REV(ret) * 3141592) /
657 			AD9523_CLK_DIST_DIV_REV(ret);
658 		*val = code / 1000000;
659 		*val2 = code % 1000000;
660 		return IIO_VAL_INT_PLUS_MICRO;
661 	default:
662 		return -EINVAL;
663 	}
664 };
665 
666 static int ad9523_write_raw(struct iio_dev *indio_dev,
667 			    struct iio_chan_spec const *chan,
668 			    int val,
669 			    int val2,
670 			    long mask)
671 {
672 	struct ad9523_state *st = iio_priv(indio_dev);
673 	unsigned int reg;
674 	int ret, tmp, code;
675 
676 	mutex_lock(&st->lock);
677 	ret = ad9523_read(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel));
678 	if (ret < 0)
679 		goto out;
680 
681 	reg = ret;
682 
683 	switch (mask) {
684 	case IIO_CHAN_INFO_RAW:
685 		if (val)
686 			reg &= ~AD9523_CLK_DIST_PWR_DOWN_EN;
687 		else
688 			reg |= AD9523_CLK_DIST_PWR_DOWN_EN;
689 		break;
690 	case IIO_CHAN_INFO_FREQUENCY:
691 		if (val <= 0) {
692 			ret = -EINVAL;
693 			goto out;
694 		}
695 		ret = ad9523_set_clock_provider(indio_dev, chan->channel, val);
696 		if (ret < 0)
697 			goto out;
698 		tmp = st->vco_out_freq[st->vco_out_map[chan->channel]] / val;
699 		tmp = clamp(tmp, 1, 1024);
700 		reg &= ~(0x3FF << 8);
701 		reg |= AD9523_CLK_DIST_DIV(tmp);
702 		break;
703 	case IIO_CHAN_INFO_PHASE:
704 		code = val * 1000000 + val2 % 1000000;
705 		tmp = (code * AD9523_CLK_DIST_DIV_REV(ret)) / 3141592;
706 		tmp = clamp(tmp, 0, 63);
707 		reg &= ~AD9523_CLK_DIST_DIV_PHASE(~0);
708 		reg |= AD9523_CLK_DIST_DIV_PHASE(tmp);
709 		break;
710 	default:
711 		ret = -EINVAL;
712 		goto out;
713 	}
714 
715 	ret = ad9523_write(indio_dev, AD9523_CHANNEL_CLOCK_DIST(chan->channel),
716 			   reg);
717 	if (ret < 0)
718 		goto out;
719 
720 	ad9523_io_update(indio_dev);
721 out:
722 	mutex_unlock(&st->lock);
723 	return ret;
724 }
725 
726 static int ad9523_reg_access(struct iio_dev *indio_dev,
727 			      unsigned int reg, unsigned int writeval,
728 			      unsigned int *readval)
729 {
730 	struct ad9523_state *st = iio_priv(indio_dev);
731 	int ret;
732 
733 	mutex_lock(&st->lock);
734 	if (readval == NULL) {
735 		ret = ad9523_write(indio_dev, reg | AD9523_R1B, writeval);
736 		ad9523_io_update(indio_dev);
737 	} else {
738 		ret = ad9523_read(indio_dev, reg | AD9523_R1B);
739 		if (ret < 0)
740 			goto out_unlock;
741 		*readval = ret;
742 		ret = 0;
743 	}
744 
745 out_unlock:
746 	mutex_unlock(&st->lock);
747 
748 	return ret;
749 }
750 
751 static const struct iio_info ad9523_info = {
752 	.read_raw = &ad9523_read_raw,
753 	.write_raw = &ad9523_write_raw,
754 	.debugfs_reg_access = &ad9523_reg_access,
755 	.attrs = &ad9523_attribute_group,
756 };
757 
758 static int ad9523_setup(struct iio_dev *indio_dev)
759 {
760 	struct ad9523_state *st = iio_priv(indio_dev);
761 	struct ad9523_platform_data *pdata = st->pdata;
762 	struct ad9523_channel_spec *chan;
763 	unsigned long active_mask = 0;
764 	int ret, i;
765 
766 	ret = ad9523_write(indio_dev, AD9523_SERIAL_PORT_CONFIG,
767 			   AD9523_SER_CONF_SOFT_RESET |
768 			  (st->spi->mode & SPI_3WIRE ? 0 :
769 			  AD9523_SER_CONF_SDO_ACTIVE));
770 	if (ret < 0)
771 		return ret;
772 
773 	ret = ad9523_write(indio_dev, AD9523_READBACK_CTRL,
774 			  AD9523_READBACK_CTRL_READ_BUFFERED);
775 	if (ret < 0)
776 		return ret;
777 
778 	ret = ad9523_io_update(indio_dev);
779 	if (ret < 0)
780 		return ret;
781 
782 	/*
783 	 * PLL1 Setup
784 	 */
785 	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_A_DIVIDER,
786 		pdata->refa_r_div);
787 	if (ret < 0)
788 		return ret;
789 
790 	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_B_DIVIDER,
791 		pdata->refb_r_div);
792 	if (ret < 0)
793 		return ret;
794 
795 	ret = ad9523_write(indio_dev, AD9523_PLL1_FEEDBACK_DIVIDER,
796 		pdata->pll1_feedback_div);
797 	if (ret < 0)
798 		return ret;
799 
800 	ret = ad9523_write(indio_dev, AD9523_PLL1_CHARGE_PUMP_CTRL,
801 		AD9523_PLL1_CHARGE_PUMP_CURRENT_nA(pdata->
802 			pll1_charge_pump_current_nA) |
803 		AD9523_PLL1_CHARGE_PUMP_MODE_NORMAL |
804 		AD9523_PLL1_BACKLASH_PW_MIN);
805 	if (ret < 0)
806 		return ret;
807 
808 	ret = ad9523_write(indio_dev, AD9523_PLL1_INPUT_RECEIVERS_CTRL,
809 		AD_IF(refa_diff_rcv_en, AD9523_PLL1_REFA_RCV_EN) |
810 		AD_IF(refb_diff_rcv_en, AD9523_PLL1_REFB_RCV_EN) |
811 		AD_IF(osc_in_diff_en, AD9523_PLL1_OSC_IN_DIFF_EN) |
812 		AD_IF(osc_in_cmos_neg_inp_en,
813 		      AD9523_PLL1_OSC_IN_CMOS_NEG_INP_EN) |
814 		AD_IF(refa_diff_rcv_en, AD9523_PLL1_REFA_DIFF_RCV_EN) |
815 		AD_IF(refb_diff_rcv_en, AD9523_PLL1_REFB_DIFF_RCV_EN));
816 	if (ret < 0)
817 		return ret;
818 
819 	ret = ad9523_write(indio_dev, AD9523_PLL1_REF_CTRL,
820 		AD_IF(zd_in_diff_en, AD9523_PLL1_ZD_IN_DIFF_EN) |
821 		AD_IF(zd_in_cmos_neg_inp_en,
822 		      AD9523_PLL1_ZD_IN_CMOS_NEG_INP_EN) |
823 		AD_IF(zero_delay_mode_internal_en,
824 		      AD9523_PLL1_ZERO_DELAY_MODE_INT) |
825 		AD_IF(osc_in_feedback_en, AD9523_PLL1_OSC_IN_PLL_FEEDBACK_EN) |
826 		AD_IF(refa_cmos_neg_inp_en, AD9523_PLL1_REFA_CMOS_NEG_INP_EN) |
827 		AD_IF(refb_cmos_neg_inp_en, AD9523_PLL1_REFB_CMOS_NEG_INP_EN));
828 	if (ret < 0)
829 		return ret;
830 
831 	ret = ad9523_write(indio_dev, AD9523_PLL1_MISC_CTRL,
832 		AD9523_PLL1_REFB_INDEP_DIV_CTRL_EN |
833 		AD9523_PLL1_REF_MODE(pdata->ref_mode));
834 	if (ret < 0)
835 		return ret;
836 
837 	ret = ad9523_write(indio_dev, AD9523_PLL1_LOOP_FILTER_CTRL,
838 		AD9523_PLL1_LOOP_FILTER_RZERO(pdata->pll1_loop_filter_rzero));
839 	if (ret < 0)
840 		return ret;
841 	/*
842 	 * PLL2 Setup
843 	 */
844 
845 	ret = ad9523_write(indio_dev, AD9523_PLL2_CHARGE_PUMP,
846 		AD9523_PLL2_CHARGE_PUMP_CURRENT_nA(pdata->
847 			pll2_charge_pump_current_nA));
848 	if (ret < 0)
849 		return ret;
850 
851 	ret = ad9523_write(indio_dev, AD9523_PLL2_FEEDBACK_DIVIDER_AB,
852 		AD9523_PLL2_FB_NDIV_A_CNT(pdata->pll2_ndiv_a_cnt) |
853 		AD9523_PLL2_FB_NDIV_B_CNT(pdata->pll2_ndiv_b_cnt));
854 	if (ret < 0)
855 		return ret;
856 
857 	ret = ad9523_write(indio_dev, AD9523_PLL2_CTRL,
858 		AD9523_PLL2_CHARGE_PUMP_MODE_NORMAL |
859 		AD9523_PLL2_BACKLASH_CTRL_EN |
860 		AD_IF(pll2_freq_doubler_en, AD9523_PLL2_FREQ_DOUBLER_EN));
861 	if (ret < 0)
862 		return ret;
863 
864 	st->vco_freq = div_u64((unsigned long long)pdata->vcxo_freq *
865 			       (pdata->pll2_freq_doubler_en ? 2 : 1) *
866 			       AD9523_PLL2_FB_NDIV(pdata->pll2_ndiv_a_cnt,
867 						   pdata->pll2_ndiv_b_cnt),
868 			       pdata->pll2_r2_div);
869 
870 	ret = ad9523_write(indio_dev, AD9523_PLL2_VCO_CTRL,
871 		AD9523_PLL2_VCO_CALIBRATE);
872 	if (ret < 0)
873 		return ret;
874 
875 	ret = ad9523_write(indio_dev, AD9523_PLL2_VCO_DIVIDER,
876 		AD9523_PLL2_VCO_DIV_M1(pdata->pll2_vco_div_m1) |
877 		AD9523_PLL2_VCO_DIV_M2(pdata->pll2_vco_div_m2) |
878 		AD_IFE(pll2_vco_div_m1, 0,
879 		       AD9523_PLL2_VCO_DIV_M1_PWR_DOWN_EN) |
880 		AD_IFE(pll2_vco_div_m2, 0,
881 		       AD9523_PLL2_VCO_DIV_M2_PWR_DOWN_EN));
882 	if (ret < 0)
883 		return ret;
884 
885 	if (pdata->pll2_vco_div_m1)
886 		st->vco_out_freq[AD9523_VCO1] =
887 			st->vco_freq / pdata->pll2_vco_div_m1;
888 
889 	if (pdata->pll2_vco_div_m2)
890 		st->vco_out_freq[AD9523_VCO2] =
891 			st->vco_freq / pdata->pll2_vco_div_m2;
892 
893 	st->vco_out_freq[AD9523_VCXO] = pdata->vcxo_freq;
894 
895 	ret = ad9523_write(indio_dev, AD9523_PLL2_R2_DIVIDER,
896 		AD9523_PLL2_R2_DIVIDER_VAL(pdata->pll2_r2_div));
897 	if (ret < 0)
898 		return ret;
899 
900 	ret = ad9523_write(indio_dev, AD9523_PLL2_LOOP_FILTER_CTRL,
901 		AD9523_PLL2_LOOP_FILTER_CPOLE1(pdata->cpole1) |
902 		AD9523_PLL2_LOOP_FILTER_RZERO(pdata->rzero) |
903 		AD9523_PLL2_LOOP_FILTER_RPOLE2(pdata->rpole2) |
904 		AD_IF(rzero_bypass_en,
905 		      AD9523_PLL2_LOOP_FILTER_RZERO_BYPASS_EN));
906 	if (ret < 0)
907 		return ret;
908 
909 	for (i = 0; i < pdata->num_channels; i++) {
910 		chan = &pdata->channels[i];
911 		if (chan->channel_num < AD9523_NUM_CHAN) {
912 			__set_bit(chan->channel_num, &active_mask);
913 			ret = ad9523_write(indio_dev,
914 				AD9523_CHANNEL_CLOCK_DIST(chan->channel_num),
915 				AD9523_CLK_DIST_DRIVER_MODE(chan->driver_mode) |
916 				AD9523_CLK_DIST_DIV(chan->channel_divider) |
917 				AD9523_CLK_DIST_DIV_PHASE(chan->divider_phase) |
918 				(chan->sync_ignore_en ?
919 					AD9523_CLK_DIST_IGNORE_SYNC_EN : 0) |
920 				(chan->divider_output_invert_en ?
921 					AD9523_CLK_DIST_INV_DIV_OUTPUT_EN : 0) |
922 				(chan->low_power_mode_en ?
923 					AD9523_CLK_DIST_LOW_PWR_MODE_EN : 0) |
924 				(chan->output_dis ?
925 					AD9523_CLK_DIST_PWR_DOWN_EN : 0));
926 			if (ret < 0)
927 				return ret;
928 
929 			ret = ad9523_vco_out_map(indio_dev, chan->channel_num,
930 					   chan->use_alt_clock_src);
931 			if (ret < 0)
932 				return ret;
933 
934 			st->ad9523_channels[i].type = IIO_ALTVOLTAGE;
935 			st->ad9523_channels[i].output = 1;
936 			st->ad9523_channels[i].indexed = 1;
937 			st->ad9523_channels[i].channel = chan->channel_num;
938 			st->ad9523_channels[i].extend_name =
939 				chan->extended_name;
940 			st->ad9523_channels[i].info_mask_separate =
941 				BIT(IIO_CHAN_INFO_RAW) |
942 				BIT(IIO_CHAN_INFO_PHASE) |
943 				BIT(IIO_CHAN_INFO_FREQUENCY);
944 		}
945 	}
946 
947 	for_each_clear_bit(i, &active_mask, AD9523_NUM_CHAN) {
948 		ret = ad9523_write(indio_dev,
949 			     AD9523_CHANNEL_CLOCK_DIST(i),
950 			     AD9523_CLK_DIST_DRIVER_MODE(TRISTATE) |
951 			     AD9523_CLK_DIST_PWR_DOWN_EN);
952 		if (ret < 0)
953 			return ret;
954 	}
955 
956 	ret = ad9523_write(indio_dev, AD9523_POWER_DOWN_CTRL, 0);
957 	if (ret < 0)
958 		return ret;
959 
960 	ret = ad9523_write(indio_dev, AD9523_STATUS_SIGNALS,
961 			   AD9523_STATUS_MONITOR_01_PLL12_LOCKED);
962 	if (ret < 0)
963 		return ret;
964 
965 	ret = ad9523_io_update(indio_dev);
966 	if (ret < 0)
967 		return ret;
968 
969 	return 0;
970 }
971 
972 static int ad9523_probe(struct spi_device *spi)
973 {
974 	struct ad9523_platform_data *pdata = spi->dev.platform_data;
975 	struct iio_dev *indio_dev;
976 	struct ad9523_state *st;
977 	int ret;
978 
979 	if (!pdata) {
980 		dev_err(&spi->dev, "no platform data?\n");
981 		return -EINVAL;
982 	}
983 
984 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
985 	if (indio_dev == NULL)
986 		return -ENOMEM;
987 
988 	st = iio_priv(indio_dev);
989 
990 	mutex_init(&st->lock);
991 
992 	st->reg = devm_regulator_get(&spi->dev, "vcc");
993 	if (!IS_ERR(st->reg)) {
994 		ret = regulator_enable(st->reg);
995 		if (ret)
996 			return ret;
997 	}
998 
999 	st->pwrdown_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown",
1000 		GPIOD_OUT_HIGH);
1001 	if (IS_ERR(st->pwrdown_gpio)) {
1002 		ret = PTR_ERR(st->pwrdown_gpio);
1003 		goto error_disable_reg;
1004 	}
1005 
1006 	st->reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset",
1007 		GPIOD_OUT_LOW);
1008 	if (IS_ERR(st->reset_gpio)) {
1009 		ret = PTR_ERR(st->reset_gpio);
1010 		goto error_disable_reg;
1011 	}
1012 
1013 	if (st->reset_gpio) {
1014 		udelay(1);
1015 		gpiod_direction_output(st->reset_gpio, 1);
1016 	}
1017 
1018 	st->sync_gpio = devm_gpiod_get_optional(&spi->dev, "sync",
1019 		GPIOD_OUT_HIGH);
1020 	if (IS_ERR(st->sync_gpio)) {
1021 		ret = PTR_ERR(st->sync_gpio);
1022 		goto error_disable_reg;
1023 	}
1024 
1025 	spi_set_drvdata(spi, indio_dev);
1026 	st->spi = spi;
1027 	st->pdata = pdata;
1028 
1029 	indio_dev->name = (pdata->name[0] != 0) ? pdata->name :
1030 			  spi_get_device_id(spi)->name;
1031 	indio_dev->info = &ad9523_info;
1032 	indio_dev->modes = INDIO_DIRECT_MODE;
1033 	indio_dev->channels = st->ad9523_channels;
1034 	indio_dev->num_channels = pdata->num_channels;
1035 
1036 	ret = ad9523_setup(indio_dev);
1037 	if (ret < 0)
1038 		goto error_disable_reg;
1039 
1040 	ret = iio_device_register(indio_dev);
1041 	if (ret)
1042 		goto error_disable_reg;
1043 
1044 	dev_info(&spi->dev, "probed %s\n", indio_dev->name);
1045 
1046 	return 0;
1047 
1048 error_disable_reg:
1049 	if (!IS_ERR(st->reg))
1050 		regulator_disable(st->reg);
1051 
1052 	return ret;
1053 }
1054 
1055 static int ad9523_remove(struct spi_device *spi)
1056 {
1057 	struct iio_dev *indio_dev = spi_get_drvdata(spi);
1058 	struct ad9523_state *st = iio_priv(indio_dev);
1059 
1060 	iio_device_unregister(indio_dev);
1061 
1062 	if (!IS_ERR(st->reg))
1063 		regulator_disable(st->reg);
1064 
1065 	return 0;
1066 }
1067 
1068 static const struct spi_device_id ad9523_id[] = {
1069 	{"ad9523-1", 9523},
1070 	{}
1071 };
1072 MODULE_DEVICE_TABLE(spi, ad9523_id);
1073 
1074 static struct spi_driver ad9523_driver = {
1075 	.driver = {
1076 		.name	= "ad9523",
1077 	},
1078 	.probe		= ad9523_probe,
1079 	.remove		= ad9523_remove,
1080 	.id_table	= ad9523_id,
1081 };
1082 module_spi_driver(ad9523_driver);
1083 
1084 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
1085 MODULE_DESCRIPTION("Analog Devices AD9523 CLOCKDIST/PLL");
1086 MODULE_LICENSE("GPL v2");
1087