1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Xilinx XADC driver
4  *
5  * Copyright 2013-2014 Analog Devices Inc.
6  *  Author: Lars-Peter Clausen <lars@metafoo.de>
7  *
8  * Documentation for the parts can be found at:
9  *  - XADC hardmacro: Xilinx UG480
10  *  - ZYNQ XADC interface: Xilinx UG585
11  *  - AXI XADC interface: Xilinx PG019
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/device.h>
16 #include <linux/err.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/overflow.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/sysfs.h>
26 
27 #include <linux/iio/buffer.h>
28 #include <linux/iio/events.h>
29 #include <linux/iio/iio.h>
30 #include <linux/iio/sysfs.h>
31 #include <linux/iio/trigger.h>
32 #include <linux/iio/trigger_consumer.h>
33 #include <linux/iio/triggered_buffer.h>
34 
35 #include "xilinx-xadc.h"
36 
37 static const unsigned int XADC_ZYNQ_UNMASK_TIMEOUT = 500;
38 
39 /* ZYNQ register definitions */
40 #define XADC_ZYNQ_REG_CFG	0x00
41 #define XADC_ZYNQ_REG_INTSTS	0x04
42 #define XADC_ZYNQ_REG_INTMSK	0x08
43 #define XADC_ZYNQ_REG_STATUS	0x0c
44 #define XADC_ZYNQ_REG_CFIFO	0x10
45 #define XADC_ZYNQ_REG_DFIFO	0x14
46 #define XADC_ZYNQ_REG_CTL		0x18
47 
48 #define XADC_ZYNQ_CFG_ENABLE		BIT(31)
49 #define XADC_ZYNQ_CFG_CFIFOTH_MASK	(0xf << 20)
50 #define XADC_ZYNQ_CFG_CFIFOTH_OFFSET	20
51 #define XADC_ZYNQ_CFG_DFIFOTH_MASK	(0xf << 16)
52 #define XADC_ZYNQ_CFG_DFIFOTH_OFFSET	16
53 #define XADC_ZYNQ_CFG_WEDGE		BIT(13)
54 #define XADC_ZYNQ_CFG_REDGE		BIT(12)
55 #define XADC_ZYNQ_CFG_TCKRATE_MASK	(0x3 << 8)
56 #define XADC_ZYNQ_CFG_TCKRATE_DIV2	(0x0 << 8)
57 #define XADC_ZYNQ_CFG_TCKRATE_DIV4	(0x1 << 8)
58 #define XADC_ZYNQ_CFG_TCKRATE_DIV8	(0x2 << 8)
59 #define XADC_ZYNQ_CFG_TCKRATE_DIV16	(0x3 << 8)
60 #define XADC_ZYNQ_CFG_IGAP_MASK		0x1f
61 #define XADC_ZYNQ_CFG_IGAP(x)		(x)
62 
63 #define XADC_ZYNQ_INT_CFIFO_LTH		BIT(9)
64 #define XADC_ZYNQ_INT_DFIFO_GTH		BIT(8)
65 #define XADC_ZYNQ_INT_ALARM_MASK	0xff
66 #define XADC_ZYNQ_INT_ALARM_OFFSET	0
67 
68 #define XADC_ZYNQ_STATUS_CFIFO_LVL_MASK	(0xf << 16)
69 #define XADC_ZYNQ_STATUS_CFIFO_LVL_OFFSET	16
70 #define XADC_ZYNQ_STATUS_DFIFO_LVL_MASK	(0xf << 12)
71 #define XADC_ZYNQ_STATUS_DFIFO_LVL_OFFSET	12
72 #define XADC_ZYNQ_STATUS_CFIFOF		BIT(11)
73 #define XADC_ZYNQ_STATUS_CFIFOE		BIT(10)
74 #define XADC_ZYNQ_STATUS_DFIFOF		BIT(9)
75 #define XADC_ZYNQ_STATUS_DFIFOE		BIT(8)
76 #define XADC_ZYNQ_STATUS_OT		BIT(7)
77 #define XADC_ZYNQ_STATUS_ALM(x)		BIT(x)
78 
79 #define XADC_ZYNQ_CTL_RESET		BIT(4)
80 
81 #define XADC_ZYNQ_CMD_NOP		0x00
82 #define XADC_ZYNQ_CMD_READ		0x01
83 #define XADC_ZYNQ_CMD_WRITE		0x02
84 
85 #define XADC_ZYNQ_CMD(cmd, addr, data) (((cmd) << 26) | ((addr) << 16) | (data))
86 
87 /* AXI register definitions */
88 #define XADC_AXI_REG_RESET		0x00
89 #define XADC_AXI_REG_STATUS		0x04
90 #define XADC_AXI_REG_ALARM_STATUS	0x08
91 #define XADC_AXI_REG_CONVST		0x0c
92 #define XADC_AXI_REG_XADC_RESET		0x10
93 #define XADC_AXI_REG_GIER		0x5c
94 #define XADC_AXI_REG_IPISR		0x60
95 #define XADC_AXI_REG_IPIER		0x68
96 
97 /* 7 Series */
98 #define XADC_7S_AXI_ADC_REG_OFFSET	0x200
99 
100 /* UltraScale */
101 #define XADC_US_AXI_ADC_REG_OFFSET	0x400
102 
103 #define XADC_AXI_RESET_MAGIC		0xa
104 #define XADC_AXI_GIER_ENABLE		BIT(31)
105 
106 #define XADC_AXI_INT_EOS		BIT(4)
107 #define XADC_AXI_INT_ALARM_MASK		0x3c0f
108 
109 #define XADC_FLAGS_BUFFERED BIT(0)
110 #define XADC_FLAGS_IRQ_OPTIONAL BIT(1)
111 
112 /*
113  * The XADC hardware supports a samplerate of up to 1MSPS. Unfortunately it does
114  * not have a hardware FIFO. Which means an interrupt is generated for each
115  * conversion sequence. At 1MSPS sample rate the CPU in ZYNQ7000 is completely
116  * overloaded by the interrupts that it soft-lockups. For this reason the driver
117  * limits the maximum samplerate 150kSPS. At this rate the CPU is fairly busy,
118  * but still responsive.
119  */
120 #define XADC_MAX_SAMPLERATE 150000
121 
122 static void xadc_write_reg(struct xadc *xadc, unsigned int reg,
123 	uint32_t val)
124 {
125 	writel(val, xadc->base + reg);
126 }
127 
128 static void xadc_read_reg(struct xadc *xadc, unsigned int reg,
129 	uint32_t *val)
130 {
131 	*val = readl(xadc->base + reg);
132 }
133 
134 /*
135  * The ZYNQ interface uses two asynchronous FIFOs for communication with the
136  * XADC. Reads and writes to the XADC register are performed by submitting a
137  * request to the command FIFO (CFIFO), once the request has been completed the
138  * result can be read from the data FIFO (DFIFO). The method currently used in
139  * this driver is to submit the request for a read/write operation, then go to
140  * sleep and wait for an interrupt that signals that a response is available in
141  * the data FIFO.
142  */
143 
144 static void xadc_zynq_write_fifo(struct xadc *xadc, uint32_t *cmd,
145 	unsigned int n)
146 {
147 	unsigned int i;
148 
149 	for (i = 0; i < n; i++)
150 		xadc_write_reg(xadc, XADC_ZYNQ_REG_CFIFO, cmd[i]);
151 }
152 
153 static void xadc_zynq_drain_fifo(struct xadc *xadc)
154 {
155 	uint32_t status, tmp;
156 
157 	xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status);
158 
159 	while (!(status & XADC_ZYNQ_STATUS_DFIFOE)) {
160 		xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp);
161 		xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status);
162 	}
163 }
164 
165 static void xadc_zynq_update_intmsk(struct xadc *xadc, unsigned int mask,
166 	unsigned int val)
167 {
168 	xadc->zynq_intmask &= ~mask;
169 	xadc->zynq_intmask |= val;
170 
171 	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK,
172 		xadc->zynq_intmask | xadc->zynq_masked_alarm);
173 }
174 
175 static int xadc_zynq_write_adc_reg(struct xadc *xadc, unsigned int reg,
176 	uint16_t val)
177 {
178 	uint32_t cmd[1];
179 	uint32_t tmp;
180 	int ret;
181 
182 	spin_lock_irq(&xadc->lock);
183 	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH,
184 			XADC_ZYNQ_INT_DFIFO_GTH);
185 
186 	reinit_completion(&xadc->completion);
187 
188 	cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_WRITE, reg, val);
189 	xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd));
190 	xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp);
191 	tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK;
192 	tmp |= 0 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET;
193 	xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp);
194 
195 	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0);
196 	spin_unlock_irq(&xadc->lock);
197 
198 	ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ);
199 	if (ret == 0)
200 		ret = -EIO;
201 	else
202 		ret = 0;
203 
204 	xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp);
205 
206 	return ret;
207 }
208 
209 static int xadc_zynq_read_adc_reg(struct xadc *xadc, unsigned int reg,
210 	uint16_t *val)
211 {
212 	uint32_t cmd[2];
213 	uint32_t resp, tmp;
214 	int ret;
215 
216 	cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_READ, reg, 0);
217 	cmd[1] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_NOP, 0, 0);
218 
219 	spin_lock_irq(&xadc->lock);
220 	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH,
221 			XADC_ZYNQ_INT_DFIFO_GTH);
222 	xadc_zynq_drain_fifo(xadc);
223 	reinit_completion(&xadc->completion);
224 
225 	xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd));
226 	xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp);
227 	tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK;
228 	tmp |= 1 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET;
229 	xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp);
230 
231 	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0);
232 	spin_unlock_irq(&xadc->lock);
233 	ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ);
234 	if (ret == 0)
235 		ret = -EIO;
236 	if (ret < 0)
237 		return ret;
238 
239 	xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp);
240 	xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp);
241 
242 	*val = resp & 0xffff;
243 
244 	return 0;
245 }
246 
247 static unsigned int xadc_zynq_transform_alarm(unsigned int alarm)
248 {
249 	return ((alarm & 0x80) >> 4) |
250 		((alarm & 0x78) << 1) |
251 		(alarm & 0x07);
252 }
253 
254 /*
255  * The ZYNQ threshold interrupts are level sensitive. Since we can't make the
256  * threshold condition go way from within the interrupt handler, this means as
257  * soon as a threshold condition is present we would enter the interrupt handler
258  * again and again. To work around this we mask all active thresholds interrupts
259  * in the interrupt handler and start a timer. In this timer we poll the
260  * interrupt status and only if the interrupt is inactive we unmask it again.
261  */
262 static void xadc_zynq_unmask_worker(struct work_struct *work)
263 {
264 	struct xadc *xadc = container_of(work, struct xadc, zynq_unmask_work.work);
265 	unsigned int misc_sts, unmask;
266 
267 	xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &misc_sts);
268 
269 	misc_sts &= XADC_ZYNQ_INT_ALARM_MASK;
270 
271 	spin_lock_irq(&xadc->lock);
272 
273 	/* Clear those bits which are not active anymore */
274 	unmask = (xadc->zynq_masked_alarm ^ misc_sts) & xadc->zynq_masked_alarm;
275 	xadc->zynq_masked_alarm &= misc_sts;
276 
277 	/* Also clear those which are masked out anyway */
278 	xadc->zynq_masked_alarm &= ~xadc->zynq_intmask;
279 
280 	/* Clear the interrupts before we unmask them */
281 	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, unmask);
282 
283 	xadc_zynq_update_intmsk(xadc, 0, 0);
284 
285 	spin_unlock_irq(&xadc->lock);
286 
287 	/* if still pending some alarm re-trigger the timer */
288 	if (xadc->zynq_masked_alarm) {
289 		schedule_delayed_work(&xadc->zynq_unmask_work,
290 				msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT));
291 	}
292 
293 }
294 
295 static irqreturn_t xadc_zynq_interrupt_handler(int irq, void *devid)
296 {
297 	struct iio_dev *indio_dev = devid;
298 	struct xadc *xadc = iio_priv(indio_dev);
299 	uint32_t status;
300 
301 	xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status);
302 
303 	status &= ~(xadc->zynq_intmask | xadc->zynq_masked_alarm);
304 
305 	if (!status)
306 		return IRQ_NONE;
307 
308 	spin_lock(&xadc->lock);
309 
310 	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status);
311 
312 	if (status & XADC_ZYNQ_INT_DFIFO_GTH) {
313 		xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH,
314 			XADC_ZYNQ_INT_DFIFO_GTH);
315 		complete(&xadc->completion);
316 	}
317 
318 	status &= XADC_ZYNQ_INT_ALARM_MASK;
319 	if (status) {
320 		xadc->zynq_masked_alarm |= status;
321 		/*
322 		 * mask the current event interrupt,
323 		 * unmask it when the interrupt is no more active.
324 		 */
325 		xadc_zynq_update_intmsk(xadc, 0, 0);
326 
327 		xadc_handle_events(indio_dev,
328 				xadc_zynq_transform_alarm(status));
329 
330 		/* unmask the required interrupts in timer. */
331 		schedule_delayed_work(&xadc->zynq_unmask_work,
332 				msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT));
333 	}
334 	spin_unlock(&xadc->lock);
335 
336 	return IRQ_HANDLED;
337 }
338 
339 #define XADC_ZYNQ_TCK_RATE_MAX 50000000
340 #define XADC_ZYNQ_IGAP_DEFAULT 20
341 #define XADC_ZYNQ_PCAP_RATE_MAX 200000000
342 
343 static int xadc_zynq_setup(struct platform_device *pdev,
344 	struct iio_dev *indio_dev, int irq)
345 {
346 	struct xadc *xadc = iio_priv(indio_dev);
347 	unsigned long pcap_rate;
348 	unsigned int tck_div;
349 	unsigned int div;
350 	unsigned int igap;
351 	unsigned int tck_rate;
352 	int ret;
353 
354 	/* TODO: Figure out how to make igap and tck_rate configurable */
355 	igap = XADC_ZYNQ_IGAP_DEFAULT;
356 	tck_rate = XADC_ZYNQ_TCK_RATE_MAX;
357 
358 	xadc->zynq_intmask = ~0;
359 
360 	pcap_rate = clk_get_rate(xadc->clk);
361 	if (!pcap_rate)
362 		return -EINVAL;
363 
364 	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
365 		ret = clk_set_rate(xadc->clk,
366 				   (unsigned long)XADC_ZYNQ_PCAP_RATE_MAX);
367 		if (ret)
368 			return ret;
369 	}
370 
371 	if (tck_rate > pcap_rate / 2) {
372 		div = 2;
373 	} else {
374 		div = pcap_rate / tck_rate;
375 		if (pcap_rate / div > XADC_ZYNQ_TCK_RATE_MAX)
376 			div++;
377 	}
378 
379 	if (div <= 3)
380 		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV2;
381 	else if (div <= 7)
382 		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV4;
383 	else if (div <= 15)
384 		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV8;
385 	else
386 		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV16;
387 
388 	xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, XADC_ZYNQ_CTL_RESET);
389 	xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, 0);
390 	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, ~0);
391 	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK, xadc->zynq_intmask);
392 	xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, XADC_ZYNQ_CFG_ENABLE |
393 			XADC_ZYNQ_CFG_REDGE | XADC_ZYNQ_CFG_WEDGE |
394 			tck_div | XADC_ZYNQ_CFG_IGAP(igap));
395 
396 	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
397 		ret = clk_set_rate(xadc->clk, pcap_rate);
398 		if (ret)
399 			return ret;
400 	}
401 
402 	return 0;
403 }
404 
405 static unsigned long xadc_zynq_get_dclk_rate(struct xadc *xadc)
406 {
407 	unsigned int div;
408 	uint32_t val;
409 
410 	xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &val);
411 
412 	switch (val & XADC_ZYNQ_CFG_TCKRATE_MASK) {
413 	case XADC_ZYNQ_CFG_TCKRATE_DIV4:
414 		div = 4;
415 		break;
416 	case XADC_ZYNQ_CFG_TCKRATE_DIV8:
417 		div = 8;
418 		break;
419 	case XADC_ZYNQ_CFG_TCKRATE_DIV16:
420 		div = 16;
421 		break;
422 	default:
423 		div = 2;
424 		break;
425 	}
426 
427 	return clk_get_rate(xadc->clk) / div;
428 }
429 
430 static void xadc_zynq_update_alarm(struct xadc *xadc, unsigned int alarm)
431 {
432 	unsigned long flags;
433 	uint32_t status;
434 
435 	/* Move OT to bit 7 */
436 	alarm = ((alarm & 0x08) << 4) | ((alarm & 0xf0) >> 1) | (alarm & 0x07);
437 
438 	spin_lock_irqsave(&xadc->lock, flags);
439 
440 	/* Clear previous interrupts if any. */
441 	xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status);
442 	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status & alarm);
443 
444 	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_ALARM_MASK,
445 		~alarm & XADC_ZYNQ_INT_ALARM_MASK);
446 
447 	spin_unlock_irqrestore(&xadc->lock, flags);
448 }
449 
450 static const struct xadc_ops xadc_zynq_ops = {
451 	.read = xadc_zynq_read_adc_reg,
452 	.write = xadc_zynq_write_adc_reg,
453 	.setup = xadc_zynq_setup,
454 	.get_dclk_rate = xadc_zynq_get_dclk_rate,
455 	.interrupt_handler = xadc_zynq_interrupt_handler,
456 	.update_alarm = xadc_zynq_update_alarm,
457 	.type = XADC_TYPE_S7,
458 };
459 
460 static const unsigned int xadc_axi_reg_offsets[] = {
461 	[XADC_TYPE_S7] = XADC_7S_AXI_ADC_REG_OFFSET,
462 	[XADC_TYPE_US] = XADC_US_AXI_ADC_REG_OFFSET,
463 };
464 
465 static int xadc_axi_read_adc_reg(struct xadc *xadc, unsigned int reg,
466 	uint16_t *val)
467 {
468 	uint32_t val32;
469 
470 	xadc_read_reg(xadc, xadc_axi_reg_offsets[xadc->ops->type] + reg * 4,
471 		&val32);
472 	*val = val32 & 0xffff;
473 
474 	return 0;
475 }
476 
477 static int xadc_axi_write_adc_reg(struct xadc *xadc, unsigned int reg,
478 	uint16_t val)
479 {
480 	xadc_write_reg(xadc, xadc_axi_reg_offsets[xadc->ops->type] + reg * 4,
481 		val);
482 
483 	return 0;
484 }
485 
486 static int xadc_axi_setup(struct platform_device *pdev,
487 	struct iio_dev *indio_dev, int irq)
488 {
489 	struct xadc *xadc = iio_priv(indio_dev);
490 
491 	xadc_write_reg(xadc, XADC_AXI_REG_RESET, XADC_AXI_RESET_MAGIC);
492 	xadc_write_reg(xadc, XADC_AXI_REG_GIER, XADC_AXI_GIER_ENABLE);
493 
494 	return 0;
495 }
496 
497 static irqreturn_t xadc_axi_interrupt_handler(int irq, void *devid)
498 {
499 	struct iio_dev *indio_dev = devid;
500 	struct xadc *xadc = iio_priv(indio_dev);
501 	uint32_t status, mask;
502 	unsigned int events;
503 
504 	xadc_read_reg(xadc, XADC_AXI_REG_IPISR, &status);
505 	xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &mask);
506 	status &= mask;
507 
508 	if (!status)
509 		return IRQ_NONE;
510 
511 	if ((status & XADC_AXI_INT_EOS) && xadc->trigger)
512 		iio_trigger_poll(xadc->trigger);
513 
514 	if (status & XADC_AXI_INT_ALARM_MASK) {
515 		/*
516 		 * The order of the bits in the AXI-XADC status register does
517 		 * not match the order of the bits in the XADC alarm enable
518 		 * register. xadc_handle_events() expects the events to be in
519 		 * the same order as the XADC alarm enable register.
520 		 */
521 		events = (status & 0x000e) >> 1;
522 		events |= (status & 0x0001) << 3;
523 		events |= (status & 0x3c00) >> 6;
524 		xadc_handle_events(indio_dev, events);
525 	}
526 
527 	xadc_write_reg(xadc, XADC_AXI_REG_IPISR, status);
528 
529 	return IRQ_HANDLED;
530 }
531 
532 static void xadc_axi_update_alarm(struct xadc *xadc, unsigned int alarm)
533 {
534 	uint32_t val;
535 	unsigned long flags;
536 
537 	/*
538 	 * The order of the bits in the AXI-XADC status register does not match
539 	 * the order of the bits in the XADC alarm enable register. We get
540 	 * passed the alarm mask in the same order as in the XADC alarm enable
541 	 * register.
542 	 */
543 	alarm = ((alarm & 0x07) << 1) | ((alarm & 0x08) >> 3) |
544 			((alarm & 0xf0) << 6);
545 
546 	spin_lock_irqsave(&xadc->lock, flags);
547 	xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val);
548 	val &= ~XADC_AXI_INT_ALARM_MASK;
549 	val |= alarm;
550 	xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val);
551 	spin_unlock_irqrestore(&xadc->lock, flags);
552 }
553 
554 static unsigned long xadc_axi_get_dclk(struct xadc *xadc)
555 {
556 	return clk_get_rate(xadc->clk);
557 }
558 
559 static const struct xadc_ops xadc_7s_axi_ops = {
560 	.read = xadc_axi_read_adc_reg,
561 	.write = xadc_axi_write_adc_reg,
562 	.setup = xadc_axi_setup,
563 	.get_dclk_rate = xadc_axi_get_dclk,
564 	.update_alarm = xadc_axi_update_alarm,
565 	.interrupt_handler = xadc_axi_interrupt_handler,
566 	.flags = XADC_FLAGS_BUFFERED | XADC_FLAGS_IRQ_OPTIONAL,
567 	.type = XADC_TYPE_S7,
568 };
569 
570 static const struct xadc_ops xadc_us_axi_ops = {
571 	.read = xadc_axi_read_adc_reg,
572 	.write = xadc_axi_write_adc_reg,
573 	.setup = xadc_axi_setup,
574 	.get_dclk_rate = xadc_axi_get_dclk,
575 	.update_alarm = xadc_axi_update_alarm,
576 	.interrupt_handler = xadc_axi_interrupt_handler,
577 	.flags = XADC_FLAGS_BUFFERED | XADC_FLAGS_IRQ_OPTIONAL,
578 	.type = XADC_TYPE_US,
579 };
580 
581 static int _xadc_update_adc_reg(struct xadc *xadc, unsigned int reg,
582 	uint16_t mask, uint16_t val)
583 {
584 	uint16_t tmp;
585 	int ret;
586 
587 	ret = _xadc_read_adc_reg(xadc, reg, &tmp);
588 	if (ret)
589 		return ret;
590 
591 	return _xadc_write_adc_reg(xadc, reg, (tmp & ~mask) | val);
592 }
593 
594 static int xadc_update_adc_reg(struct xadc *xadc, unsigned int reg,
595 	uint16_t mask, uint16_t val)
596 {
597 	int ret;
598 
599 	mutex_lock(&xadc->mutex);
600 	ret = _xadc_update_adc_reg(xadc, reg, mask, val);
601 	mutex_unlock(&xadc->mutex);
602 
603 	return ret;
604 }
605 
606 static unsigned long xadc_get_dclk_rate(struct xadc *xadc)
607 {
608 	return xadc->ops->get_dclk_rate(xadc);
609 }
610 
611 static int xadc_update_scan_mode(struct iio_dev *indio_dev,
612 	const unsigned long *mask)
613 {
614 	struct xadc *xadc = iio_priv(indio_dev);
615 	size_t new_size, n;
616 	void *data;
617 
618 	n = bitmap_weight(mask, indio_dev->masklength);
619 
620 	if (check_mul_overflow(n, sizeof(*xadc->data), &new_size))
621 		return -ENOMEM;
622 
623 	data = devm_krealloc(indio_dev->dev.parent, xadc->data,
624 			     new_size, GFP_KERNEL);
625 	if (!data)
626 		return -ENOMEM;
627 
628 	memset(data, 0, new_size);
629 	xadc->data = data;
630 
631 	return 0;
632 }
633 
634 static unsigned int xadc_scan_index_to_channel(unsigned int scan_index)
635 {
636 	switch (scan_index) {
637 	case 5:
638 		return XADC_REG_VCCPINT;
639 	case 6:
640 		return XADC_REG_VCCPAUX;
641 	case 7:
642 		return XADC_REG_VCCO_DDR;
643 	case 8:
644 		return XADC_REG_TEMP;
645 	case 9:
646 		return XADC_REG_VCCINT;
647 	case 10:
648 		return XADC_REG_VCCAUX;
649 	case 11:
650 		return XADC_REG_VPVN;
651 	case 12:
652 		return XADC_REG_VREFP;
653 	case 13:
654 		return XADC_REG_VREFN;
655 	case 14:
656 		return XADC_REG_VCCBRAM;
657 	default:
658 		return XADC_REG_VAUX(scan_index - 16);
659 	}
660 }
661 
662 static irqreturn_t xadc_trigger_handler(int irq, void *p)
663 {
664 	struct iio_poll_func *pf = p;
665 	struct iio_dev *indio_dev = pf->indio_dev;
666 	struct xadc *xadc = iio_priv(indio_dev);
667 	unsigned int chan;
668 	int i, j;
669 
670 	if (!xadc->data)
671 		goto out;
672 
673 	j = 0;
674 	for_each_set_bit(i, indio_dev->active_scan_mask,
675 		indio_dev->masklength) {
676 		chan = xadc_scan_index_to_channel(i);
677 		xadc_read_adc_reg(xadc, chan, &xadc->data[j]);
678 		j++;
679 	}
680 
681 	iio_push_to_buffers(indio_dev, xadc->data);
682 
683 out:
684 	iio_trigger_notify_done(indio_dev->trig);
685 
686 	return IRQ_HANDLED;
687 }
688 
689 static int xadc_trigger_set_state(struct iio_trigger *trigger, bool state)
690 {
691 	struct xadc *xadc = iio_trigger_get_drvdata(trigger);
692 	unsigned long flags;
693 	unsigned int convst;
694 	unsigned int val;
695 	int ret = 0;
696 
697 	mutex_lock(&xadc->mutex);
698 
699 	if (state) {
700 		/* Only one of the two triggers can be active at a time. */
701 		if (xadc->trigger != NULL) {
702 			ret = -EBUSY;
703 			goto err_out;
704 		} else {
705 			xadc->trigger = trigger;
706 			if (trigger == xadc->convst_trigger)
707 				convst = XADC_CONF0_EC;
708 			else
709 				convst = 0;
710 		}
711 		ret = _xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF0_EC,
712 					convst);
713 		if (ret)
714 			goto err_out;
715 	} else {
716 		xadc->trigger = NULL;
717 	}
718 
719 	spin_lock_irqsave(&xadc->lock, flags);
720 	xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val);
721 	xadc_write_reg(xadc, XADC_AXI_REG_IPISR, XADC_AXI_INT_EOS);
722 	if (state)
723 		val |= XADC_AXI_INT_EOS;
724 	else
725 		val &= ~XADC_AXI_INT_EOS;
726 	xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val);
727 	spin_unlock_irqrestore(&xadc->lock, flags);
728 
729 err_out:
730 	mutex_unlock(&xadc->mutex);
731 
732 	return ret;
733 }
734 
735 static const struct iio_trigger_ops xadc_trigger_ops = {
736 	.set_trigger_state = &xadc_trigger_set_state,
737 };
738 
739 static struct iio_trigger *xadc_alloc_trigger(struct iio_dev *indio_dev,
740 	const char *name)
741 {
742 	struct device *dev = indio_dev->dev.parent;
743 	struct iio_trigger *trig;
744 	int ret;
745 
746 	trig = devm_iio_trigger_alloc(dev, "%s%d-%s", indio_dev->name,
747 				      iio_device_id(indio_dev), name);
748 	if (trig == NULL)
749 		return ERR_PTR(-ENOMEM);
750 
751 	trig->ops = &xadc_trigger_ops;
752 	iio_trigger_set_drvdata(trig, iio_priv(indio_dev));
753 
754 	ret = devm_iio_trigger_register(dev, trig);
755 	if (ret)
756 		return ERR_PTR(ret);
757 
758 	return trig;
759 }
760 
761 static int xadc_power_adc_b(struct xadc *xadc, unsigned int seq_mode)
762 {
763 	uint16_t val;
764 
765 	/*
766 	 * As per datasheet the power-down bits are don't care in the
767 	 * UltraScale, but as per reality setting the power-down bit for the
768 	 * non-existing ADC-B powers down the main ADC, so just return and don't
769 	 * do anything.
770 	 */
771 	if (xadc->ops->type == XADC_TYPE_US)
772 		return 0;
773 
774 	/* Powerdown the ADC-B when it is not needed. */
775 	switch (seq_mode) {
776 	case XADC_CONF1_SEQ_SIMULTANEOUS:
777 	case XADC_CONF1_SEQ_INDEPENDENT:
778 		val = 0;
779 		break;
780 	default:
781 		val = XADC_CONF2_PD_ADC_B;
782 		break;
783 	}
784 
785 	return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_PD_MASK,
786 		val);
787 }
788 
789 static int xadc_get_seq_mode(struct xadc *xadc, unsigned long scan_mode)
790 {
791 	unsigned int aux_scan_mode = scan_mode >> 16;
792 
793 	/* UltraScale has only one ADC and supports only continuous mode */
794 	if (xadc->ops->type == XADC_TYPE_US)
795 		return XADC_CONF1_SEQ_CONTINUOUS;
796 
797 	if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_DUAL)
798 		return XADC_CONF1_SEQ_SIMULTANEOUS;
799 
800 	if ((aux_scan_mode & 0xff00) == 0 ||
801 		(aux_scan_mode & 0x00ff) == 0)
802 		return XADC_CONF1_SEQ_CONTINUOUS;
803 
804 	return XADC_CONF1_SEQ_SIMULTANEOUS;
805 }
806 
807 static int xadc_postdisable(struct iio_dev *indio_dev)
808 {
809 	struct xadc *xadc = iio_priv(indio_dev);
810 	unsigned long scan_mask;
811 	int ret;
812 	int i;
813 
814 	scan_mask = 1; /* Run calibration as part of the sequence */
815 	for (i = 0; i < indio_dev->num_channels; i++)
816 		scan_mask |= BIT(indio_dev->channels[i].scan_index);
817 
818 	/* Enable all channels and calibration */
819 	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff);
820 	if (ret)
821 		return ret;
822 
823 	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16);
824 	if (ret)
825 		return ret;
826 
827 	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK,
828 		XADC_CONF1_SEQ_CONTINUOUS);
829 	if (ret)
830 		return ret;
831 
832 	return xadc_power_adc_b(xadc, XADC_CONF1_SEQ_CONTINUOUS);
833 }
834 
835 static int xadc_preenable(struct iio_dev *indio_dev)
836 {
837 	struct xadc *xadc = iio_priv(indio_dev);
838 	unsigned long scan_mask;
839 	int seq_mode;
840 	int ret;
841 
842 	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK,
843 		XADC_CONF1_SEQ_DEFAULT);
844 	if (ret)
845 		goto err;
846 
847 	scan_mask = *indio_dev->active_scan_mask;
848 	seq_mode = xadc_get_seq_mode(xadc, scan_mask);
849 
850 	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff);
851 	if (ret)
852 		goto err;
853 
854 	/*
855 	 * In simultaneous mode the upper and lower aux channels are samples at
856 	 * the same time. In this mode the upper 8 bits in the sequencer
857 	 * register are don't care and the lower 8 bits control two channels
858 	 * each. As such we must set the bit if either the channel in the lower
859 	 * group or the upper group is enabled.
860 	 */
861 	if (seq_mode == XADC_CONF1_SEQ_SIMULTANEOUS)
862 		scan_mask = ((scan_mask >> 8) | scan_mask) & 0xff0000;
863 
864 	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16);
865 	if (ret)
866 		goto err;
867 
868 	ret = xadc_power_adc_b(xadc, seq_mode);
869 	if (ret)
870 		goto err;
871 
872 	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK,
873 		seq_mode);
874 	if (ret)
875 		goto err;
876 
877 	return 0;
878 err:
879 	xadc_postdisable(indio_dev);
880 	return ret;
881 }
882 
883 static const struct iio_buffer_setup_ops xadc_buffer_ops = {
884 	.preenable = &xadc_preenable,
885 	.postdisable = &xadc_postdisable,
886 };
887 
888 static int xadc_read_samplerate(struct xadc *xadc)
889 {
890 	unsigned int div;
891 	uint16_t val16;
892 	int ret;
893 
894 	ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, &val16);
895 	if (ret)
896 		return ret;
897 
898 	div = (val16 & XADC_CONF2_DIV_MASK) >> XADC_CONF2_DIV_OFFSET;
899 	if (div < 2)
900 		div = 2;
901 
902 	return xadc_get_dclk_rate(xadc) / div / 26;
903 }
904 
905 static int xadc_read_raw(struct iio_dev *indio_dev,
906 	struct iio_chan_spec const *chan, int *val, int *val2, long info)
907 {
908 	struct xadc *xadc = iio_priv(indio_dev);
909 	unsigned int bits = chan->scan_type.realbits;
910 	uint16_t val16;
911 	int ret;
912 
913 	switch (info) {
914 	case IIO_CHAN_INFO_RAW:
915 		if (iio_buffer_enabled(indio_dev))
916 			return -EBUSY;
917 		ret = xadc_read_adc_reg(xadc, chan->address, &val16);
918 		if (ret < 0)
919 			return ret;
920 
921 		val16 >>= chan->scan_type.shift;
922 		if (chan->scan_type.sign == 'u')
923 			*val = val16;
924 		else
925 			*val = sign_extend32(val16, bits - 1);
926 
927 		return IIO_VAL_INT;
928 	case IIO_CHAN_INFO_SCALE:
929 		switch (chan->type) {
930 		case IIO_VOLTAGE:
931 			/* V = (val * 3.0) / 2**bits */
932 			switch (chan->address) {
933 			case XADC_REG_VCCINT:
934 			case XADC_REG_VCCAUX:
935 			case XADC_REG_VREFP:
936 			case XADC_REG_VREFN:
937 			case XADC_REG_VCCBRAM:
938 			case XADC_REG_VCCPINT:
939 			case XADC_REG_VCCPAUX:
940 			case XADC_REG_VCCO_DDR:
941 				*val = 3000;
942 				break;
943 			default:
944 				*val = 1000;
945 				break;
946 			}
947 			*val2 = bits;
948 			return IIO_VAL_FRACTIONAL_LOG2;
949 		case IIO_TEMP:
950 			/* Temp in C = (val * 503.975) / 2**bits - 273.15 */
951 			*val = 503975;
952 			*val2 = bits;
953 			return IIO_VAL_FRACTIONAL_LOG2;
954 		default:
955 			return -EINVAL;
956 		}
957 	case IIO_CHAN_INFO_OFFSET:
958 		/* Only the temperature channel has an offset */
959 		*val = -((273150 << bits) / 503975);
960 		return IIO_VAL_INT;
961 	case IIO_CHAN_INFO_SAMP_FREQ:
962 		ret = xadc_read_samplerate(xadc);
963 		if (ret < 0)
964 			return ret;
965 
966 		*val = ret;
967 		return IIO_VAL_INT;
968 	default:
969 		return -EINVAL;
970 	}
971 }
972 
973 static int xadc_write_samplerate(struct xadc *xadc, int val)
974 {
975 	unsigned long clk_rate = xadc_get_dclk_rate(xadc);
976 	unsigned int div;
977 
978 	if (!clk_rate)
979 		return -EINVAL;
980 
981 	if (val <= 0)
982 		return -EINVAL;
983 
984 	/* Max. 150 kSPS */
985 	if (val > XADC_MAX_SAMPLERATE)
986 		val = XADC_MAX_SAMPLERATE;
987 
988 	val *= 26;
989 
990 	/* Min 1MHz */
991 	if (val < 1000000)
992 		val = 1000000;
993 
994 	/*
995 	 * We want to round down, but only if we do not exceed the 150 kSPS
996 	 * limit.
997 	 */
998 	div = clk_rate / val;
999 	if (clk_rate / div / 26 > XADC_MAX_SAMPLERATE)
1000 		div++;
1001 	if (div < 2)
1002 		div = 2;
1003 	else if (div > 0xff)
1004 		div = 0xff;
1005 
1006 	return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_DIV_MASK,
1007 		div << XADC_CONF2_DIV_OFFSET);
1008 }
1009 
1010 static int xadc_write_raw(struct iio_dev *indio_dev,
1011 	struct iio_chan_spec const *chan, int val, int val2, long info)
1012 {
1013 	struct xadc *xadc = iio_priv(indio_dev);
1014 
1015 	if (info != IIO_CHAN_INFO_SAMP_FREQ)
1016 		return -EINVAL;
1017 
1018 	return xadc_write_samplerate(xadc, val);
1019 }
1020 
1021 static const struct iio_event_spec xadc_temp_events[] = {
1022 	{
1023 		.type = IIO_EV_TYPE_THRESH,
1024 		.dir = IIO_EV_DIR_RISING,
1025 		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
1026 				BIT(IIO_EV_INFO_VALUE) |
1027 				BIT(IIO_EV_INFO_HYSTERESIS),
1028 	},
1029 };
1030 
1031 /* Separate values for upper and lower thresholds, but only a shared enabled */
1032 static const struct iio_event_spec xadc_voltage_events[] = {
1033 	{
1034 		.type = IIO_EV_TYPE_THRESH,
1035 		.dir = IIO_EV_DIR_RISING,
1036 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
1037 	}, {
1038 		.type = IIO_EV_TYPE_THRESH,
1039 		.dir = IIO_EV_DIR_FALLING,
1040 		.mask_separate = BIT(IIO_EV_INFO_VALUE),
1041 	}, {
1042 		.type = IIO_EV_TYPE_THRESH,
1043 		.dir = IIO_EV_DIR_EITHER,
1044 		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
1045 	},
1046 };
1047 
1048 #define XADC_CHAN_TEMP(_chan, _scan_index, _addr, _bits) { \
1049 	.type = IIO_TEMP, \
1050 	.indexed = 1, \
1051 	.channel = (_chan), \
1052 	.address = (_addr), \
1053 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1054 		BIT(IIO_CHAN_INFO_SCALE) | \
1055 		BIT(IIO_CHAN_INFO_OFFSET), \
1056 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
1057 	.event_spec = xadc_temp_events, \
1058 	.num_event_specs = ARRAY_SIZE(xadc_temp_events), \
1059 	.scan_index = (_scan_index), \
1060 	.scan_type = { \
1061 		.sign = 'u', \
1062 		.realbits = (_bits), \
1063 		.storagebits = 16, \
1064 		.shift = 16 - (_bits), \
1065 		.endianness = IIO_CPU, \
1066 	}, \
1067 }
1068 
1069 #define XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, _bits, _ext, _alarm) { \
1070 	.type = IIO_VOLTAGE, \
1071 	.indexed = 1, \
1072 	.channel = (_chan), \
1073 	.address = (_addr), \
1074 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1075 		BIT(IIO_CHAN_INFO_SCALE), \
1076 	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
1077 	.event_spec = (_alarm) ? xadc_voltage_events : NULL, \
1078 	.num_event_specs = (_alarm) ? ARRAY_SIZE(xadc_voltage_events) : 0, \
1079 	.scan_index = (_scan_index), \
1080 	.scan_type = { \
1081 		.sign = ((_addr) == XADC_REG_VREFN) ? 's' : 'u', \
1082 		.realbits = (_bits), \
1083 		.storagebits = 16, \
1084 		.shift = 16 - (_bits), \
1085 		.endianness = IIO_CPU, \
1086 	}, \
1087 	.extend_name = _ext, \
1088 }
1089 
1090 /* 7 Series */
1091 #define XADC_7S_CHAN_TEMP(_chan, _scan_index, _addr) \
1092 	XADC_CHAN_TEMP(_chan, _scan_index, _addr, 12)
1093 #define XADC_7S_CHAN_VOLTAGE(_chan, _scan_index, _addr, _ext, _alarm) \
1094 	XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, 12, _ext, _alarm)
1095 
1096 static const struct iio_chan_spec xadc_7s_channels[] = {
1097 	XADC_7S_CHAN_TEMP(0, 8, XADC_REG_TEMP),
1098 	XADC_7S_CHAN_VOLTAGE(0, 9, XADC_REG_VCCINT, "vccint", true),
1099 	XADC_7S_CHAN_VOLTAGE(1, 10, XADC_REG_VCCAUX, "vccaux", true),
1100 	XADC_7S_CHAN_VOLTAGE(2, 14, XADC_REG_VCCBRAM, "vccbram", true),
1101 	XADC_7S_CHAN_VOLTAGE(3, 5, XADC_REG_VCCPINT, "vccpint", true),
1102 	XADC_7S_CHAN_VOLTAGE(4, 6, XADC_REG_VCCPAUX, "vccpaux", true),
1103 	XADC_7S_CHAN_VOLTAGE(5, 7, XADC_REG_VCCO_DDR, "vccoddr", true),
1104 	XADC_7S_CHAN_VOLTAGE(6, 12, XADC_REG_VREFP, "vrefp", false),
1105 	XADC_7S_CHAN_VOLTAGE(7, 13, XADC_REG_VREFN, "vrefn", false),
1106 	XADC_7S_CHAN_VOLTAGE(8, 11, XADC_REG_VPVN, NULL, false),
1107 	XADC_7S_CHAN_VOLTAGE(9, 16, XADC_REG_VAUX(0), NULL, false),
1108 	XADC_7S_CHAN_VOLTAGE(10, 17, XADC_REG_VAUX(1), NULL, false),
1109 	XADC_7S_CHAN_VOLTAGE(11, 18, XADC_REG_VAUX(2), NULL, false),
1110 	XADC_7S_CHAN_VOLTAGE(12, 19, XADC_REG_VAUX(3), NULL, false),
1111 	XADC_7S_CHAN_VOLTAGE(13, 20, XADC_REG_VAUX(4), NULL, false),
1112 	XADC_7S_CHAN_VOLTAGE(14, 21, XADC_REG_VAUX(5), NULL, false),
1113 	XADC_7S_CHAN_VOLTAGE(15, 22, XADC_REG_VAUX(6), NULL, false),
1114 	XADC_7S_CHAN_VOLTAGE(16, 23, XADC_REG_VAUX(7), NULL, false),
1115 	XADC_7S_CHAN_VOLTAGE(17, 24, XADC_REG_VAUX(8), NULL, false),
1116 	XADC_7S_CHAN_VOLTAGE(18, 25, XADC_REG_VAUX(9), NULL, false),
1117 	XADC_7S_CHAN_VOLTAGE(19, 26, XADC_REG_VAUX(10), NULL, false),
1118 	XADC_7S_CHAN_VOLTAGE(20, 27, XADC_REG_VAUX(11), NULL, false),
1119 	XADC_7S_CHAN_VOLTAGE(21, 28, XADC_REG_VAUX(12), NULL, false),
1120 	XADC_7S_CHAN_VOLTAGE(22, 29, XADC_REG_VAUX(13), NULL, false),
1121 	XADC_7S_CHAN_VOLTAGE(23, 30, XADC_REG_VAUX(14), NULL, false),
1122 	XADC_7S_CHAN_VOLTAGE(24, 31, XADC_REG_VAUX(15), NULL, false),
1123 };
1124 
1125 /* UltraScale */
1126 #define XADC_US_CHAN_TEMP(_chan, _scan_index, _addr) \
1127 	XADC_CHAN_TEMP(_chan, _scan_index, _addr, 10)
1128 #define XADC_US_CHAN_VOLTAGE(_chan, _scan_index, _addr, _ext, _alarm) \
1129 	XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, 10, _ext, _alarm)
1130 
1131 static const struct iio_chan_spec xadc_us_channels[] = {
1132 	XADC_US_CHAN_TEMP(0, 8, XADC_REG_TEMP),
1133 	XADC_US_CHAN_VOLTAGE(0, 9, XADC_REG_VCCINT, "vccint", true),
1134 	XADC_US_CHAN_VOLTAGE(1, 10, XADC_REG_VCCAUX, "vccaux", true),
1135 	XADC_US_CHAN_VOLTAGE(2, 14, XADC_REG_VCCBRAM, "vccbram", true),
1136 	XADC_US_CHAN_VOLTAGE(3, 5, XADC_REG_VCCPINT, "vccpsintlp", true),
1137 	XADC_US_CHAN_VOLTAGE(4, 6, XADC_REG_VCCPAUX, "vccpsintfp", true),
1138 	XADC_US_CHAN_VOLTAGE(5, 7, XADC_REG_VCCO_DDR, "vccpsaux", true),
1139 	XADC_US_CHAN_VOLTAGE(6, 12, XADC_REG_VREFP, "vrefp", false),
1140 	XADC_US_CHAN_VOLTAGE(7, 13, XADC_REG_VREFN, "vrefn", false),
1141 	XADC_US_CHAN_VOLTAGE(8, 11, XADC_REG_VPVN, NULL, false),
1142 	XADC_US_CHAN_VOLTAGE(9, 16, XADC_REG_VAUX(0), NULL, false),
1143 	XADC_US_CHAN_VOLTAGE(10, 17, XADC_REG_VAUX(1), NULL, false),
1144 	XADC_US_CHAN_VOLTAGE(11, 18, XADC_REG_VAUX(2), NULL, false),
1145 	XADC_US_CHAN_VOLTAGE(12, 19, XADC_REG_VAUX(3), NULL, false),
1146 	XADC_US_CHAN_VOLTAGE(13, 20, XADC_REG_VAUX(4), NULL, false),
1147 	XADC_US_CHAN_VOLTAGE(14, 21, XADC_REG_VAUX(5), NULL, false),
1148 	XADC_US_CHAN_VOLTAGE(15, 22, XADC_REG_VAUX(6), NULL, false),
1149 	XADC_US_CHAN_VOLTAGE(16, 23, XADC_REG_VAUX(7), NULL, false),
1150 	XADC_US_CHAN_VOLTAGE(17, 24, XADC_REG_VAUX(8), NULL, false),
1151 	XADC_US_CHAN_VOLTAGE(18, 25, XADC_REG_VAUX(9), NULL, false),
1152 	XADC_US_CHAN_VOLTAGE(19, 26, XADC_REG_VAUX(10), NULL, false),
1153 	XADC_US_CHAN_VOLTAGE(20, 27, XADC_REG_VAUX(11), NULL, false),
1154 	XADC_US_CHAN_VOLTAGE(21, 28, XADC_REG_VAUX(12), NULL, false),
1155 	XADC_US_CHAN_VOLTAGE(22, 29, XADC_REG_VAUX(13), NULL, false),
1156 	XADC_US_CHAN_VOLTAGE(23, 30, XADC_REG_VAUX(14), NULL, false),
1157 	XADC_US_CHAN_VOLTAGE(24, 31, XADC_REG_VAUX(15), NULL, false),
1158 };
1159 
1160 static const struct iio_info xadc_info = {
1161 	.read_raw = &xadc_read_raw,
1162 	.write_raw = &xadc_write_raw,
1163 	.read_event_config = &xadc_read_event_config,
1164 	.write_event_config = &xadc_write_event_config,
1165 	.read_event_value = &xadc_read_event_value,
1166 	.write_event_value = &xadc_write_event_value,
1167 	.update_scan_mode = &xadc_update_scan_mode,
1168 };
1169 
1170 static const struct of_device_id xadc_of_match_table[] = {
1171 	{
1172 		.compatible = "xlnx,zynq-xadc-1.00.a",
1173 		.data = &xadc_zynq_ops
1174 	}, {
1175 		.compatible = "xlnx,axi-xadc-1.00.a",
1176 		.data = &xadc_7s_axi_ops
1177 	}, {
1178 		.compatible = "xlnx,system-management-wiz-1.3",
1179 		.data = &xadc_us_axi_ops
1180 	},
1181 	{ },
1182 };
1183 MODULE_DEVICE_TABLE(of, xadc_of_match_table);
1184 
1185 static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np,
1186 	unsigned int *conf, int irq)
1187 {
1188 	struct device *dev = indio_dev->dev.parent;
1189 	struct xadc *xadc = iio_priv(indio_dev);
1190 	const struct iio_chan_spec *channel_templates;
1191 	struct iio_chan_spec *channels, *chan;
1192 	struct device_node *chan_node, *child;
1193 	unsigned int max_channels;
1194 	unsigned int num_channels;
1195 	const char *external_mux;
1196 	u32 ext_mux_chan;
1197 	u32 reg;
1198 	int ret;
1199 	int i;
1200 
1201 	*conf = 0;
1202 
1203 	ret = of_property_read_string(np, "xlnx,external-mux", &external_mux);
1204 	if (ret < 0 || strcasecmp(external_mux, "none") == 0)
1205 		xadc->external_mux_mode = XADC_EXTERNAL_MUX_NONE;
1206 	else if (strcasecmp(external_mux, "single") == 0)
1207 		xadc->external_mux_mode = XADC_EXTERNAL_MUX_SINGLE;
1208 	else if (strcasecmp(external_mux, "dual") == 0)
1209 		xadc->external_mux_mode = XADC_EXTERNAL_MUX_DUAL;
1210 	else
1211 		return -EINVAL;
1212 
1213 	if (xadc->external_mux_mode != XADC_EXTERNAL_MUX_NONE) {
1214 		ret = of_property_read_u32(np, "xlnx,external-mux-channel",
1215 					&ext_mux_chan);
1216 		if (ret < 0)
1217 			return ret;
1218 
1219 		if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_SINGLE) {
1220 			if (ext_mux_chan == 0)
1221 				ext_mux_chan = XADC_REG_VPVN;
1222 			else if (ext_mux_chan <= 16)
1223 				ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1);
1224 			else
1225 				return -EINVAL;
1226 		} else {
1227 			if (ext_mux_chan > 0 && ext_mux_chan <= 8)
1228 				ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1);
1229 			else
1230 				return -EINVAL;
1231 		}
1232 
1233 		*conf |= XADC_CONF0_MUX | XADC_CONF0_CHAN(ext_mux_chan);
1234 	}
1235 	if (xadc->ops->type == XADC_TYPE_S7) {
1236 		channel_templates = xadc_7s_channels;
1237 		max_channels = ARRAY_SIZE(xadc_7s_channels);
1238 	} else {
1239 		channel_templates = xadc_us_channels;
1240 		max_channels = ARRAY_SIZE(xadc_us_channels);
1241 	}
1242 	channels = devm_kmemdup(dev, channel_templates,
1243 				sizeof(channels[0]) * max_channels, GFP_KERNEL);
1244 	if (!channels)
1245 		return -ENOMEM;
1246 
1247 	num_channels = 9;
1248 	chan = &channels[9];
1249 
1250 	chan_node = of_get_child_by_name(np, "xlnx,channels");
1251 	if (chan_node) {
1252 		for_each_child_of_node(chan_node, child) {
1253 			if (num_channels >= max_channels) {
1254 				of_node_put(child);
1255 				break;
1256 			}
1257 
1258 			ret = of_property_read_u32(child, "reg", &reg);
1259 			if (ret || reg > 16)
1260 				continue;
1261 
1262 			if (of_property_read_bool(child, "xlnx,bipolar"))
1263 				chan->scan_type.sign = 's';
1264 
1265 			if (reg == 0) {
1266 				chan->scan_index = 11;
1267 				chan->address = XADC_REG_VPVN;
1268 			} else {
1269 				chan->scan_index = 15 + reg;
1270 				chan->address = XADC_REG_VAUX(reg - 1);
1271 			}
1272 			num_channels++;
1273 			chan++;
1274 		}
1275 	}
1276 	of_node_put(chan_node);
1277 
1278 	/* No IRQ => no events */
1279 	if (irq <= 0) {
1280 		for (i = 0; i < num_channels; i++) {
1281 			channels[i].event_spec = NULL;
1282 			channels[i].num_event_specs = 0;
1283 		}
1284 	}
1285 
1286 	indio_dev->num_channels = num_channels;
1287 	indio_dev->channels = devm_krealloc(dev, channels,
1288 					    sizeof(*channels) * num_channels,
1289 					    GFP_KERNEL);
1290 	/* If we can't resize the channels array, just use the original */
1291 	if (!indio_dev->channels)
1292 		indio_dev->channels = channels;
1293 
1294 	return 0;
1295 }
1296 
1297 static const char * const xadc_type_names[] = {
1298 	[XADC_TYPE_S7] = "xadc",
1299 	[XADC_TYPE_US] = "xilinx-system-monitor",
1300 };
1301 
1302 static void xadc_clk_disable_unprepare(void *data)
1303 {
1304 	struct clk *clk = data;
1305 
1306 	clk_disable_unprepare(clk);
1307 }
1308 
1309 static void xadc_cancel_delayed_work(void *data)
1310 {
1311 	struct delayed_work *work = data;
1312 
1313 	cancel_delayed_work_sync(work);
1314 }
1315 
1316 static int xadc_probe(struct platform_device *pdev)
1317 {
1318 	struct device *dev = &pdev->dev;
1319 	const struct of_device_id *id;
1320 	const struct xadc_ops *ops;
1321 	struct iio_dev *indio_dev;
1322 	unsigned int bipolar_mask;
1323 	unsigned int conf0;
1324 	struct xadc *xadc;
1325 	int ret;
1326 	int irq;
1327 	int i;
1328 
1329 	if (!dev->of_node)
1330 		return -ENODEV;
1331 
1332 	id = of_match_node(xadc_of_match_table, dev->of_node);
1333 	if (!id)
1334 		return -EINVAL;
1335 
1336 	ops = id->data;
1337 
1338 	irq = platform_get_irq_optional(pdev, 0);
1339 	if (irq < 0 &&
1340 	    (irq != -ENXIO || !(ops->flags & XADC_FLAGS_IRQ_OPTIONAL)))
1341 		return irq;
1342 
1343 	indio_dev = devm_iio_device_alloc(dev, sizeof(*xadc));
1344 	if (!indio_dev)
1345 		return -ENOMEM;
1346 
1347 	xadc = iio_priv(indio_dev);
1348 	xadc->ops = id->data;
1349 	init_completion(&xadc->completion);
1350 	mutex_init(&xadc->mutex);
1351 	spin_lock_init(&xadc->lock);
1352 	INIT_DELAYED_WORK(&xadc->zynq_unmask_work, xadc_zynq_unmask_worker);
1353 
1354 	xadc->base = devm_platform_ioremap_resource(pdev, 0);
1355 	if (IS_ERR(xadc->base))
1356 		return PTR_ERR(xadc->base);
1357 
1358 	indio_dev->name = xadc_type_names[xadc->ops->type];
1359 	indio_dev->modes = INDIO_DIRECT_MODE;
1360 	indio_dev->info = &xadc_info;
1361 
1362 	ret = xadc_parse_dt(indio_dev, dev->of_node, &conf0, irq);
1363 	if (ret)
1364 		return ret;
1365 
1366 	if (xadc->ops->flags & XADC_FLAGS_BUFFERED) {
1367 		ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
1368 						      &iio_pollfunc_store_time,
1369 						      &xadc_trigger_handler,
1370 						      &xadc_buffer_ops);
1371 		if (ret)
1372 			return ret;
1373 
1374 		if (irq > 0) {
1375 			xadc->convst_trigger = xadc_alloc_trigger(indio_dev, "convst");
1376 			if (IS_ERR(xadc->convst_trigger))
1377 				return PTR_ERR(xadc->convst_trigger);
1378 
1379 			xadc->samplerate_trigger = xadc_alloc_trigger(indio_dev,
1380 				"samplerate");
1381 			if (IS_ERR(xadc->samplerate_trigger))
1382 				return PTR_ERR(xadc->samplerate_trigger);
1383 		}
1384 	}
1385 
1386 	xadc->clk = devm_clk_get(dev, NULL);
1387 	if (IS_ERR(xadc->clk))
1388 		return PTR_ERR(xadc->clk);
1389 
1390 	ret = clk_prepare_enable(xadc->clk);
1391 	if (ret)
1392 		return ret;
1393 
1394 	ret = devm_add_action_or_reset(dev,
1395 				       xadc_clk_disable_unprepare, xadc->clk);
1396 	if (ret)
1397 		return ret;
1398 
1399 	/*
1400 	 * Make sure not to exceed the maximum samplerate since otherwise the
1401 	 * resulting interrupt storm will soft-lock the system.
1402 	 */
1403 	if (xadc->ops->flags & XADC_FLAGS_BUFFERED) {
1404 		ret = xadc_read_samplerate(xadc);
1405 		if (ret < 0)
1406 			return ret;
1407 
1408 		if (ret > XADC_MAX_SAMPLERATE) {
1409 			ret = xadc_write_samplerate(xadc, XADC_MAX_SAMPLERATE);
1410 			if (ret < 0)
1411 				return ret;
1412 		}
1413 	}
1414 
1415 	if (irq > 0) {
1416 		ret = devm_request_irq(dev, irq, xadc->ops->interrupt_handler,
1417 				       0, dev_name(dev), indio_dev);
1418 		if (ret)
1419 			return ret;
1420 
1421 		ret = devm_add_action_or_reset(dev, xadc_cancel_delayed_work,
1422 					       &xadc->zynq_unmask_work);
1423 		if (ret)
1424 			return ret;
1425 	}
1426 
1427 	ret = xadc->ops->setup(pdev, indio_dev, irq);
1428 	if (ret)
1429 		return ret;
1430 
1431 	for (i = 0; i < 16; i++)
1432 		xadc_read_adc_reg(xadc, XADC_REG_THRESHOLD(i),
1433 			&xadc->threshold[i]);
1434 
1435 	ret = xadc_write_adc_reg(xadc, XADC_REG_CONF0, conf0);
1436 	if (ret)
1437 		return ret;
1438 
1439 	bipolar_mask = 0;
1440 	for (i = 0; i < indio_dev->num_channels; i++) {
1441 		if (indio_dev->channels[i].scan_type.sign == 's')
1442 			bipolar_mask |= BIT(indio_dev->channels[i].scan_index);
1443 	}
1444 
1445 	ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(0), bipolar_mask);
1446 	if (ret)
1447 		return ret;
1448 
1449 	ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(1),
1450 		bipolar_mask >> 16);
1451 	if (ret)
1452 		return ret;
1453 
1454 	/* Disable all alarms */
1455 	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_ALARM_MASK,
1456 				  XADC_CONF1_ALARM_MASK);
1457 	if (ret)
1458 		return ret;
1459 
1460 	/* Set thresholds to min/max */
1461 	for (i = 0; i < 16; i++) {
1462 		/*
1463 		 * Set max voltage threshold and both temperature thresholds to
1464 		 * 0xffff, min voltage threshold to 0.
1465 		 */
1466 		if (i % 8 < 4 || i == 7)
1467 			xadc->threshold[i] = 0xffff;
1468 		else
1469 			xadc->threshold[i] = 0;
1470 		ret = xadc_write_adc_reg(xadc, XADC_REG_THRESHOLD(i),
1471 			xadc->threshold[i]);
1472 		if (ret)
1473 			return ret;
1474 	}
1475 
1476 	/* Go to non-buffered mode */
1477 	xadc_postdisable(indio_dev);
1478 
1479 	return devm_iio_device_register(dev, indio_dev);
1480 }
1481 
1482 static struct platform_driver xadc_driver = {
1483 	.probe = xadc_probe,
1484 	.driver = {
1485 		.name = "xadc",
1486 		.of_match_table = xadc_of_match_table,
1487 	},
1488 };
1489 module_platform_driver(xadc_driver);
1490 
1491 MODULE_LICENSE("GPL v2");
1492 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
1493 MODULE_DESCRIPTION("Xilinx XADC IIO driver");
1494