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/mod_devicetable.h>
21#include <linux/module.h>
22#include <linux/overflow.h>
23#include <linux/platform_device.h>
24#include <linux/property.h>
25#include <linux/slab.h>
26#include <linux/sysfs.h>
27
28#include <linux/iio/buffer.h>
29#include <linux/iio/events.h>
30#include <linux/iio/iio.h>
31#include <linux/iio/sysfs.h>
32#include <linux/iio/trigger.h>
33#include <linux/iio/trigger_consumer.h>
34#include <linux/iio/triggered_buffer.h>
35
36#include "xilinx-xadc.h"
37
38static const unsigned int XADC_ZYNQ_UNMASK_TIMEOUT = 500;
39
40/* ZYNQ register definitions */
41#define XADC_ZYNQ_REG_CFG	0x00
42#define XADC_ZYNQ_REG_INTSTS	0x04
43#define XADC_ZYNQ_REG_INTMSK	0x08
44#define XADC_ZYNQ_REG_STATUS	0x0c
45#define XADC_ZYNQ_REG_CFIFO	0x10
46#define XADC_ZYNQ_REG_DFIFO	0x14
47#define XADC_ZYNQ_REG_CTL		0x18
48
49#define XADC_ZYNQ_CFG_ENABLE		BIT(31)
50#define XADC_ZYNQ_CFG_CFIFOTH_MASK	(0xf << 20)
51#define XADC_ZYNQ_CFG_CFIFOTH_OFFSET	20
52#define XADC_ZYNQ_CFG_DFIFOTH_MASK	(0xf << 16)
53#define XADC_ZYNQ_CFG_DFIFOTH_OFFSET	16
54#define XADC_ZYNQ_CFG_WEDGE		BIT(13)
55#define XADC_ZYNQ_CFG_REDGE		BIT(12)
56#define XADC_ZYNQ_CFG_TCKRATE_MASK	(0x3 << 8)
57#define XADC_ZYNQ_CFG_TCKRATE_DIV2	(0x0 << 8)
58#define XADC_ZYNQ_CFG_TCKRATE_DIV4	(0x1 << 8)
59#define XADC_ZYNQ_CFG_TCKRATE_DIV8	(0x2 << 8)
60#define XADC_ZYNQ_CFG_TCKRATE_DIV16	(0x3 << 8)
61#define XADC_ZYNQ_CFG_IGAP_MASK		0x1f
62#define XADC_ZYNQ_CFG_IGAP(x)		(x)
63
64#define XADC_ZYNQ_INT_CFIFO_LTH		BIT(9)
65#define XADC_ZYNQ_INT_DFIFO_GTH		BIT(8)
66#define XADC_ZYNQ_INT_ALARM_MASK	0xff
67#define XADC_ZYNQ_INT_ALARM_OFFSET	0
68
69#define XADC_ZYNQ_STATUS_CFIFO_LVL_MASK	(0xf << 16)
70#define XADC_ZYNQ_STATUS_CFIFO_LVL_OFFSET	16
71#define XADC_ZYNQ_STATUS_DFIFO_LVL_MASK	(0xf << 12)
72#define XADC_ZYNQ_STATUS_DFIFO_LVL_OFFSET	12
73#define XADC_ZYNQ_STATUS_CFIFOF		BIT(11)
74#define XADC_ZYNQ_STATUS_CFIFOE		BIT(10)
75#define XADC_ZYNQ_STATUS_DFIFOF		BIT(9)
76#define XADC_ZYNQ_STATUS_DFIFOE		BIT(8)
77#define XADC_ZYNQ_STATUS_OT		BIT(7)
78#define XADC_ZYNQ_STATUS_ALM(x)		BIT(x)
79
80#define XADC_ZYNQ_CTL_RESET		BIT(4)
81
82#define XADC_ZYNQ_CMD_NOP		0x00
83#define XADC_ZYNQ_CMD_READ		0x01
84#define XADC_ZYNQ_CMD_WRITE		0x02
85
86#define XADC_ZYNQ_CMD(cmd, addr, data) (((cmd) << 26) | ((addr) << 16) | (data))
87
88/* AXI register definitions */
89#define XADC_AXI_REG_RESET		0x00
90#define XADC_AXI_REG_STATUS		0x04
91#define XADC_AXI_REG_ALARM_STATUS	0x08
92#define XADC_AXI_REG_CONVST		0x0c
93#define XADC_AXI_REG_XADC_RESET		0x10
94#define XADC_AXI_REG_GIER		0x5c
95#define XADC_AXI_REG_IPISR		0x60
96#define XADC_AXI_REG_IPIER		0x68
97
98/* 7 Series */
99#define XADC_7S_AXI_ADC_REG_OFFSET	0x200
100
101/* UltraScale */
102#define XADC_US_AXI_ADC_REG_OFFSET	0x400
103
104#define XADC_AXI_RESET_MAGIC		0xa
105#define XADC_AXI_GIER_ENABLE		BIT(31)
106
107#define XADC_AXI_INT_EOS		BIT(4)
108#define XADC_AXI_INT_ALARM_MASK		0x3c0f
109
110#define XADC_FLAGS_BUFFERED BIT(0)
111#define XADC_FLAGS_IRQ_OPTIONAL BIT(1)
112
113/*
114 * The XADC hardware supports a samplerate of up to 1MSPS. Unfortunately it does
115 * not have a hardware FIFO. Which means an interrupt is generated for each
116 * conversion sequence. At 1MSPS sample rate the CPU in ZYNQ7000 is completely
117 * overloaded by the interrupts that it soft-lockups. For this reason the driver
118 * limits the maximum samplerate 150kSPS. At this rate the CPU is fairly busy,
119 * but still responsive.
120 */
121#define XADC_MAX_SAMPLERATE 150000
122
123static void xadc_write_reg(struct xadc *xadc, unsigned int reg,
124	uint32_t val)
125{
126	writel(val, xadc->base + reg);
127}
128
129static void xadc_read_reg(struct xadc *xadc, unsigned int reg,
130	uint32_t *val)
131{
132	*val = readl(xadc->base + reg);
133}
134
135/*
136 * The ZYNQ interface uses two asynchronous FIFOs for communication with the
137 * XADC. Reads and writes to the XADC register are performed by submitting a
138 * request to the command FIFO (CFIFO), once the request has been completed the
139 * result can be read from the data FIFO (DFIFO). The method currently used in
140 * this driver is to submit the request for a read/write operation, then go to
141 * sleep and wait for an interrupt that signals that a response is available in
142 * the data FIFO.
143 */
144
145static void xadc_zynq_write_fifo(struct xadc *xadc, uint32_t *cmd,
146	unsigned int n)
147{
148	unsigned int i;
149
150	for (i = 0; i < n; i++)
151		xadc_write_reg(xadc, XADC_ZYNQ_REG_CFIFO, cmd[i]);
152}
153
154static void xadc_zynq_drain_fifo(struct xadc *xadc)
155{
156	uint32_t status, tmp;
157
158	xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status);
159
160	while (!(status & XADC_ZYNQ_STATUS_DFIFOE)) {
161		xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp);
162		xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status);
163	}
164}
165
166static void xadc_zynq_update_intmsk(struct xadc *xadc, unsigned int mask,
167	unsigned int val)
168{
169	xadc->zynq_intmask &= ~mask;
170	xadc->zynq_intmask |= val;
171
172	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK,
173		xadc->zynq_intmask | xadc->zynq_masked_alarm);
174}
175
176static int xadc_zynq_write_adc_reg(struct xadc *xadc, unsigned int reg,
177	uint16_t val)
178{
179	uint32_t cmd[1];
180	uint32_t tmp;
181	int ret;
182
183	spin_lock_irq(&xadc->lock);
184	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH,
185			XADC_ZYNQ_INT_DFIFO_GTH);
186
187	reinit_completion(&xadc->completion);
188
189	cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_WRITE, reg, val);
190	xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd));
191	xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp);
192	tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK;
193	tmp |= 0 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET;
194	xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp);
195
196	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0);
197	spin_unlock_irq(&xadc->lock);
198
199	ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ);
200	if (ret == 0)
201		ret = -EIO;
202	else
203		ret = 0;
204
205	xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp);
206
207	return ret;
208}
209
210static int xadc_zynq_read_adc_reg(struct xadc *xadc, unsigned int reg,
211	uint16_t *val)
212{
213	uint32_t cmd[2];
214	uint32_t resp, tmp;
215	int ret;
216
217	cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_READ, reg, 0);
218	cmd[1] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_NOP, 0, 0);
219
220	spin_lock_irq(&xadc->lock);
221	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH,
222			XADC_ZYNQ_INT_DFIFO_GTH);
223	xadc_zynq_drain_fifo(xadc);
224	reinit_completion(&xadc->completion);
225
226	xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd));
227	xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp);
228	tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK;
229	tmp |= 1 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET;
230	xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp);
231
232	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0);
233	spin_unlock_irq(&xadc->lock);
234	ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ);
235	if (ret == 0)
236		ret = -EIO;
237	if (ret < 0)
238		return ret;
239
240	xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp);
241	xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp);
242
243	*val = resp & 0xffff;
244
245	return 0;
246}
247
248static unsigned int xadc_zynq_transform_alarm(unsigned int alarm)
249{
250	return ((alarm & 0x80) >> 4) |
251		((alarm & 0x78) << 1) |
252		(alarm & 0x07);
253}
254
255/*
256 * The ZYNQ threshold interrupts are level sensitive. Since we can't make the
257 * threshold condition go way from within the interrupt handler, this means as
258 * soon as a threshold condition is present we would enter the interrupt handler
259 * again and again. To work around this we mask all active thresholds interrupts
260 * in the interrupt handler and start a timer. In this timer we poll the
261 * interrupt status and only if the interrupt is inactive we unmask it again.
262 */
263static void xadc_zynq_unmask_worker(struct work_struct *work)
264{
265	struct xadc *xadc = container_of(work, struct xadc, zynq_unmask_work.work);
266	unsigned int misc_sts, unmask;
267
268	xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &misc_sts);
269
270	misc_sts &= XADC_ZYNQ_INT_ALARM_MASK;
271
272	spin_lock_irq(&xadc->lock);
273
274	/* Clear those bits which are not active anymore */
275	unmask = (xadc->zynq_masked_alarm ^ misc_sts) & xadc->zynq_masked_alarm;
276	xadc->zynq_masked_alarm &= misc_sts;
277
278	/* Also clear those which are masked out anyway */
279	xadc->zynq_masked_alarm &= ~xadc->zynq_intmask;
280
281	/* Clear the interrupts before we unmask them */
282	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, unmask);
283
284	xadc_zynq_update_intmsk(xadc, 0, 0);
285
286	spin_unlock_irq(&xadc->lock);
287
288	/* if still pending some alarm re-trigger the timer */
289	if (xadc->zynq_masked_alarm) {
290		schedule_delayed_work(&xadc->zynq_unmask_work,
291				msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT));
292	}
293
294}
295
296static irqreturn_t xadc_zynq_interrupt_handler(int irq, void *devid)
297{
298	struct iio_dev *indio_dev = devid;
299	struct xadc *xadc = iio_priv(indio_dev);
300	uint32_t status;
301
302	xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status);
303
304	status &= ~(xadc->zynq_intmask | xadc->zynq_masked_alarm);
305
306	if (!status)
307		return IRQ_NONE;
308
309	spin_lock(&xadc->lock);
310
311	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status);
312
313	if (status & XADC_ZYNQ_INT_DFIFO_GTH) {
314		xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH,
315			XADC_ZYNQ_INT_DFIFO_GTH);
316		complete(&xadc->completion);
317	}
318
319	status &= XADC_ZYNQ_INT_ALARM_MASK;
320	if (status) {
321		xadc->zynq_masked_alarm |= status;
322		/*
323		 * mask the current event interrupt,
324		 * unmask it when the interrupt is no more active.
325		 */
326		xadc_zynq_update_intmsk(xadc, 0, 0);
327
328		xadc_handle_events(indio_dev,
329				xadc_zynq_transform_alarm(status));
330
331		/* unmask the required interrupts in timer. */
332		schedule_delayed_work(&xadc->zynq_unmask_work,
333				msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT));
334	}
335	spin_unlock(&xadc->lock);
336
337	return IRQ_HANDLED;
338}
339
340#define XADC_ZYNQ_TCK_RATE_MAX 50000000
341#define XADC_ZYNQ_IGAP_DEFAULT 20
342#define XADC_ZYNQ_PCAP_RATE_MAX 200000000
343
344static int xadc_zynq_setup(struct platform_device *pdev,
345	struct iio_dev *indio_dev, int irq)
346{
347	struct xadc *xadc = iio_priv(indio_dev);
348	unsigned long pcap_rate;
349	unsigned int tck_div;
350	unsigned int div;
351	unsigned int igap;
352	unsigned int tck_rate;
353	int ret;
354
355	/* TODO: Figure out how to make igap and tck_rate configurable */
356	igap = XADC_ZYNQ_IGAP_DEFAULT;
357	tck_rate = XADC_ZYNQ_TCK_RATE_MAX;
358
359	xadc->zynq_intmask = ~0;
360
361	pcap_rate = clk_get_rate(xadc->clk);
362	if (!pcap_rate)
363		return -EINVAL;
364
365	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
366		ret = clk_set_rate(xadc->clk,
367				   (unsigned long)XADC_ZYNQ_PCAP_RATE_MAX);
368		if (ret)
369			return ret;
370	}
371
372	if (tck_rate > pcap_rate / 2) {
373		div = 2;
374	} else {
375		div = pcap_rate / tck_rate;
376		if (pcap_rate / div > XADC_ZYNQ_TCK_RATE_MAX)
377			div++;
378	}
379
380	if (div <= 3)
381		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV2;
382	else if (div <= 7)
383		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV4;
384	else if (div <= 15)
385		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV8;
386	else
387		tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV16;
388
389	xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, XADC_ZYNQ_CTL_RESET);
390	xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, 0);
391	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, ~0);
392	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK, xadc->zynq_intmask);
393	xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, XADC_ZYNQ_CFG_ENABLE |
394			XADC_ZYNQ_CFG_REDGE | XADC_ZYNQ_CFG_WEDGE |
395			tck_div | XADC_ZYNQ_CFG_IGAP(igap));
396
397	if (pcap_rate > XADC_ZYNQ_PCAP_RATE_MAX) {
398		ret = clk_set_rate(xadc->clk, pcap_rate);
399		if (ret)
400			return ret;
401	}
402
403	return 0;
404}
405
406static unsigned long xadc_zynq_get_dclk_rate(struct xadc *xadc)
407{
408	unsigned int div;
409	uint32_t val;
410
411	xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &val);
412
413	switch (val & XADC_ZYNQ_CFG_TCKRATE_MASK) {
414	case XADC_ZYNQ_CFG_TCKRATE_DIV4:
415		div = 4;
416		break;
417	case XADC_ZYNQ_CFG_TCKRATE_DIV8:
418		div = 8;
419		break;
420	case XADC_ZYNQ_CFG_TCKRATE_DIV16:
421		div = 16;
422		break;
423	default:
424		div = 2;
425		break;
426	}
427
428	return clk_get_rate(xadc->clk) / div;
429}
430
431static void xadc_zynq_update_alarm(struct xadc *xadc, unsigned int alarm)
432{
433	unsigned long flags;
434	uint32_t status;
435
436	/* Move OT to bit 7 */
437	alarm = ((alarm & 0x08) << 4) | ((alarm & 0xf0) >> 1) | (alarm & 0x07);
438
439	spin_lock_irqsave(&xadc->lock, flags);
440
441	/* Clear previous interrupts if any. */
442	xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status);
443	xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status & alarm);
444
445	xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_ALARM_MASK,
446		~alarm & XADC_ZYNQ_INT_ALARM_MASK);
447
448	spin_unlock_irqrestore(&xadc->lock, flags);
449}
450
451static const struct xadc_ops xadc_zynq_ops = {
452	.read = xadc_zynq_read_adc_reg,
453	.write = xadc_zynq_write_adc_reg,
454	.setup = xadc_zynq_setup,
455	.get_dclk_rate = xadc_zynq_get_dclk_rate,
456	.interrupt_handler = xadc_zynq_interrupt_handler,
457	.update_alarm = xadc_zynq_update_alarm,
458	.type = XADC_TYPE_S7,
459	/* Temp in C = (val * 503.975) / 2**bits - 273.15 */
460	.temp_scale = 503975,
461	.temp_offset = 273150,
462};
463
464static const unsigned int xadc_axi_reg_offsets[] = {
465	[XADC_TYPE_S7] = XADC_7S_AXI_ADC_REG_OFFSET,
466	[XADC_TYPE_US] = XADC_US_AXI_ADC_REG_OFFSET,
467};
468
469static int xadc_axi_read_adc_reg(struct xadc *xadc, unsigned int reg,
470	uint16_t *val)
471{
472	uint32_t val32;
473
474	xadc_read_reg(xadc, xadc_axi_reg_offsets[xadc->ops->type] + reg * 4,
475		&val32);
476	*val = val32 & 0xffff;
477
478	return 0;
479}
480
481static int xadc_axi_write_adc_reg(struct xadc *xadc, unsigned int reg,
482	uint16_t val)
483{
484	xadc_write_reg(xadc, xadc_axi_reg_offsets[xadc->ops->type] + reg * 4,
485		val);
486
487	return 0;
488}
489
490static int xadc_axi_setup(struct platform_device *pdev,
491	struct iio_dev *indio_dev, int irq)
492{
493	struct xadc *xadc = iio_priv(indio_dev);
494
495	xadc_write_reg(xadc, XADC_AXI_REG_RESET, XADC_AXI_RESET_MAGIC);
496	xadc_write_reg(xadc, XADC_AXI_REG_GIER, XADC_AXI_GIER_ENABLE);
497
498	return 0;
499}
500
501static irqreturn_t xadc_axi_interrupt_handler(int irq, void *devid)
502{
503	struct iio_dev *indio_dev = devid;
504	struct xadc *xadc = iio_priv(indio_dev);
505	uint32_t status, mask;
506	unsigned int events;
507
508	xadc_read_reg(xadc, XADC_AXI_REG_IPISR, &status);
509	xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &mask);
510	status &= mask;
511
512	if (!status)
513		return IRQ_NONE;
514
515	if ((status & XADC_AXI_INT_EOS) && xadc->trigger)
516		iio_trigger_poll(xadc->trigger);
517
518	if (status & XADC_AXI_INT_ALARM_MASK) {
519		/*
520		 * The order of the bits in the AXI-XADC status register does
521		 * not match the order of the bits in the XADC alarm enable
522		 * register. xadc_handle_events() expects the events to be in
523		 * the same order as the XADC alarm enable register.
524		 */
525		events = (status & 0x000e) >> 1;
526		events |= (status & 0x0001) << 3;
527		events |= (status & 0x3c00) >> 6;
528		xadc_handle_events(indio_dev, events);
529	}
530
531	xadc_write_reg(xadc, XADC_AXI_REG_IPISR, status);
532
533	return IRQ_HANDLED;
534}
535
536static void xadc_axi_update_alarm(struct xadc *xadc, unsigned int alarm)
537{
538	uint32_t val;
539	unsigned long flags;
540
541	/*
542	 * The order of the bits in the AXI-XADC status register does not match
543	 * the order of the bits in the XADC alarm enable register. We get
544	 * passed the alarm mask in the same order as in the XADC alarm enable
545	 * register.
546	 */
547	alarm = ((alarm & 0x07) << 1) | ((alarm & 0x08) >> 3) |
548			((alarm & 0xf0) << 6);
549
550	spin_lock_irqsave(&xadc->lock, flags);
551	xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val);
552	val &= ~XADC_AXI_INT_ALARM_MASK;
553	val |= alarm;
554	xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val);
555	spin_unlock_irqrestore(&xadc->lock, flags);
556}
557
558static unsigned long xadc_axi_get_dclk(struct xadc *xadc)
559{
560	return clk_get_rate(xadc->clk);
561}
562
563static const struct xadc_ops xadc_7s_axi_ops = {
564	.read = xadc_axi_read_adc_reg,
565	.write = xadc_axi_write_adc_reg,
566	.setup = xadc_axi_setup,
567	.get_dclk_rate = xadc_axi_get_dclk,
568	.update_alarm = xadc_axi_update_alarm,
569	.interrupt_handler = xadc_axi_interrupt_handler,
570	.flags = XADC_FLAGS_BUFFERED | XADC_FLAGS_IRQ_OPTIONAL,
571	.type = XADC_TYPE_S7,
572	/* Temp in C = (val * 503.975) / 2**bits - 273.15 */
573	.temp_scale = 503975,
574	.temp_offset = 273150,
575};
576
577static const struct xadc_ops xadc_us_axi_ops = {
578	.read = xadc_axi_read_adc_reg,
579	.write = xadc_axi_write_adc_reg,
580	.setup = xadc_axi_setup,
581	.get_dclk_rate = xadc_axi_get_dclk,
582	.update_alarm = xadc_axi_update_alarm,
583	.interrupt_handler = xadc_axi_interrupt_handler,
584	.flags = XADC_FLAGS_BUFFERED | XADC_FLAGS_IRQ_OPTIONAL,
585	.type = XADC_TYPE_US,
586	/**
587	 * Values below are for UltraScale+ (SYSMONE4) using internal reference.
588	 * See https://docs.xilinx.com/v/u/en-US/ug580-ultrascale-sysmon
589	 */
590	.temp_scale = 509314,
591	.temp_offset = 280231,
592};
593
594static int _xadc_update_adc_reg(struct xadc *xadc, unsigned int reg,
595	uint16_t mask, uint16_t val)
596{
597	uint16_t tmp;
598	int ret;
599
600	ret = _xadc_read_adc_reg(xadc, reg, &tmp);
601	if (ret)
602		return ret;
603
604	return _xadc_write_adc_reg(xadc, reg, (tmp & ~mask) | val);
605}
606
607static int xadc_update_adc_reg(struct xadc *xadc, unsigned int reg,
608	uint16_t mask, uint16_t val)
609{
610	int ret;
611
612	mutex_lock(&xadc->mutex);
613	ret = _xadc_update_adc_reg(xadc, reg, mask, val);
614	mutex_unlock(&xadc->mutex);
615
616	return ret;
617}
618
619static unsigned long xadc_get_dclk_rate(struct xadc *xadc)
620{
621	return xadc->ops->get_dclk_rate(xadc);
622}
623
624static int xadc_update_scan_mode(struct iio_dev *indio_dev,
625	const unsigned long *mask)
626{
627	struct xadc *xadc = iio_priv(indio_dev);
628	size_t n;
629	void *data;
630
631	n = bitmap_weight(mask, indio_dev->masklength);
632
633	data = devm_krealloc_array(indio_dev->dev.parent, xadc->data,
634				   n, sizeof(*xadc->data), GFP_KERNEL);
635	if (!data)
636		return -ENOMEM;
637
638	memset(data, 0, n * sizeof(*xadc->data));
639	xadc->data = data;
640
641	return 0;
642}
643
644static unsigned int xadc_scan_index_to_channel(unsigned int scan_index)
645{
646	switch (scan_index) {
647	case 5:
648		return XADC_REG_VCCPINT;
649	case 6:
650		return XADC_REG_VCCPAUX;
651	case 7:
652		return XADC_REG_VCCO_DDR;
653	case 8:
654		return XADC_REG_TEMP;
655	case 9:
656		return XADC_REG_VCCINT;
657	case 10:
658		return XADC_REG_VCCAUX;
659	case 11:
660		return XADC_REG_VPVN;
661	case 12:
662		return XADC_REG_VREFP;
663	case 13:
664		return XADC_REG_VREFN;
665	case 14:
666		return XADC_REG_VCCBRAM;
667	default:
668		return XADC_REG_VAUX(scan_index - 16);
669	}
670}
671
672static irqreturn_t xadc_trigger_handler(int irq, void *p)
673{
674	struct iio_poll_func *pf = p;
675	struct iio_dev *indio_dev = pf->indio_dev;
676	struct xadc *xadc = iio_priv(indio_dev);
677	unsigned int chan;
678	int i, j;
679
680	if (!xadc->data)
681		goto out;
682
683	j = 0;
684	for_each_set_bit(i, indio_dev->active_scan_mask,
685		indio_dev->masklength) {
686		chan = xadc_scan_index_to_channel(i);
687		xadc_read_adc_reg(xadc, chan, &xadc->data[j]);
688		j++;
689	}
690
691	iio_push_to_buffers(indio_dev, xadc->data);
692
693out:
694	iio_trigger_notify_done(indio_dev->trig);
695
696	return IRQ_HANDLED;
697}
698
699static int xadc_trigger_set_state(struct iio_trigger *trigger, bool state)
700{
701	struct xadc *xadc = iio_trigger_get_drvdata(trigger);
702	unsigned long flags;
703	unsigned int convst;
704	unsigned int val;
705	int ret = 0;
706
707	mutex_lock(&xadc->mutex);
708
709	if (state) {
710		/* Only one of the two triggers can be active at a time. */
711		if (xadc->trigger != NULL) {
712			ret = -EBUSY;
713			goto err_out;
714		} else {
715			xadc->trigger = trigger;
716			if (trigger == xadc->convst_trigger)
717				convst = XADC_CONF0_EC;
718			else
719				convst = 0;
720		}
721		ret = _xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF0_EC,
722					convst);
723		if (ret)
724			goto err_out;
725	} else {
726		xadc->trigger = NULL;
727	}
728
729	spin_lock_irqsave(&xadc->lock, flags);
730	xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val);
731	xadc_write_reg(xadc, XADC_AXI_REG_IPISR, XADC_AXI_INT_EOS);
732	if (state)
733		val |= XADC_AXI_INT_EOS;
734	else
735		val &= ~XADC_AXI_INT_EOS;
736	xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val);
737	spin_unlock_irqrestore(&xadc->lock, flags);
738
739err_out:
740	mutex_unlock(&xadc->mutex);
741
742	return ret;
743}
744
745static const struct iio_trigger_ops xadc_trigger_ops = {
746	.set_trigger_state = &xadc_trigger_set_state,
747};
748
749static struct iio_trigger *xadc_alloc_trigger(struct iio_dev *indio_dev,
750	const char *name)
751{
752	struct device *dev = indio_dev->dev.parent;
753	struct iio_trigger *trig;
754	int ret;
755
756	trig = devm_iio_trigger_alloc(dev, "%s%d-%s", indio_dev->name,
757				      iio_device_id(indio_dev), name);
758	if (trig == NULL)
759		return ERR_PTR(-ENOMEM);
760
761	trig->ops = &xadc_trigger_ops;
762	iio_trigger_set_drvdata(trig, iio_priv(indio_dev));
763
764	ret = devm_iio_trigger_register(dev, trig);
765	if (ret)
766		return ERR_PTR(ret);
767
768	return trig;
769}
770
771static int xadc_power_adc_b(struct xadc *xadc, unsigned int seq_mode)
772{
773	uint16_t val;
774
775	/*
776	 * As per datasheet the power-down bits are don't care in the
777	 * UltraScale, but as per reality setting the power-down bit for the
778	 * non-existing ADC-B powers down the main ADC, so just return and don't
779	 * do anything.
780	 */
781	if (xadc->ops->type == XADC_TYPE_US)
782		return 0;
783
784	/* Powerdown the ADC-B when it is not needed. */
785	switch (seq_mode) {
786	case XADC_CONF1_SEQ_SIMULTANEOUS:
787	case XADC_CONF1_SEQ_INDEPENDENT:
788		val = 0;
789		break;
790	default:
791		val = XADC_CONF2_PD_ADC_B;
792		break;
793	}
794
795	return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_PD_MASK,
796		val);
797}
798
799static int xadc_get_seq_mode(struct xadc *xadc, unsigned long scan_mode)
800{
801	unsigned int aux_scan_mode = scan_mode >> 16;
802
803	/* UltraScale has only one ADC and supports only continuous mode */
804	if (xadc->ops->type == XADC_TYPE_US)
805		return XADC_CONF1_SEQ_CONTINUOUS;
806
807	if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_DUAL)
808		return XADC_CONF1_SEQ_SIMULTANEOUS;
809
810	if ((aux_scan_mode & 0xff00) == 0 ||
811		(aux_scan_mode & 0x00ff) == 0)
812		return XADC_CONF1_SEQ_CONTINUOUS;
813
814	return XADC_CONF1_SEQ_SIMULTANEOUS;
815}
816
817static int xadc_postdisable(struct iio_dev *indio_dev)
818{
819	struct xadc *xadc = iio_priv(indio_dev);
820	unsigned long scan_mask;
821	int ret;
822	int i;
823
824	scan_mask = 1; /* Run calibration as part of the sequence */
825	for (i = 0; i < indio_dev->num_channels; i++)
826		scan_mask |= BIT(indio_dev->channels[i].scan_index);
827
828	/* Enable all channels and calibration */
829	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff);
830	if (ret)
831		return ret;
832
833	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16);
834	if (ret)
835		return ret;
836
837	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK,
838		XADC_CONF1_SEQ_CONTINUOUS);
839	if (ret)
840		return ret;
841
842	return xadc_power_adc_b(xadc, XADC_CONF1_SEQ_CONTINUOUS);
843}
844
845static int xadc_preenable(struct iio_dev *indio_dev)
846{
847	struct xadc *xadc = iio_priv(indio_dev);
848	unsigned long scan_mask;
849	int seq_mode;
850	int ret;
851
852	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK,
853		XADC_CONF1_SEQ_DEFAULT);
854	if (ret)
855		goto err;
856
857	scan_mask = *indio_dev->active_scan_mask;
858	seq_mode = xadc_get_seq_mode(xadc, scan_mask);
859
860	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff);
861	if (ret)
862		goto err;
863
864	/*
865	 * In simultaneous mode the upper and lower aux channels are samples at
866	 * the same time. In this mode the upper 8 bits in the sequencer
867	 * register are don't care and the lower 8 bits control two channels
868	 * each. As such we must set the bit if either the channel in the lower
869	 * group or the upper group is enabled.
870	 */
871	if (seq_mode == XADC_CONF1_SEQ_SIMULTANEOUS)
872		scan_mask = ((scan_mask >> 8) | scan_mask) & 0xff0000;
873
874	ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16);
875	if (ret)
876		goto err;
877
878	ret = xadc_power_adc_b(xadc, seq_mode);
879	if (ret)
880		goto err;
881
882	ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK,
883		seq_mode);
884	if (ret)
885		goto err;
886
887	return 0;
888err:
889	xadc_postdisable(indio_dev);
890	return ret;
891}
892
893static const struct iio_buffer_setup_ops xadc_buffer_ops = {
894	.preenable = &xadc_preenable,
895	.postdisable = &xadc_postdisable,
896};
897
898static int xadc_read_samplerate(struct xadc *xadc)
899{
900	unsigned int div;
901	uint16_t val16;
902	int ret;
903
904	ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, &val16);
905	if (ret)
906		return ret;
907
908	div = (val16 & XADC_CONF2_DIV_MASK) >> XADC_CONF2_DIV_OFFSET;
909	if (div < 2)
910		div = 2;
911
912	return xadc_get_dclk_rate(xadc) / div / 26;
913}
914
915static int xadc_read_raw(struct iio_dev *indio_dev,
916	struct iio_chan_spec const *chan, int *val, int *val2, long info)
917{
918	struct xadc *xadc = iio_priv(indio_dev);
919	unsigned int bits = chan->scan_type.realbits;
920	uint16_t val16;
921	int ret;
922
923	switch (info) {
924	case IIO_CHAN_INFO_RAW:
925		if (iio_buffer_enabled(indio_dev))
926			return -EBUSY;
927		ret = xadc_read_adc_reg(xadc, chan->address, &val16);
928		if (ret < 0)
929			return ret;
930
931		val16 >>= chan->scan_type.shift;
932		if (chan->scan_type.sign == 'u')
933			*val = val16;
934		else
935			*val = sign_extend32(val16, bits - 1);
936
937		return IIO_VAL_INT;
938	case IIO_CHAN_INFO_SCALE:
939		switch (chan->type) {
940		case IIO_VOLTAGE:
941			/* V = (val * 3.0) / 2**bits */
942			switch (chan->address) {
943			case XADC_REG_VCCINT:
944			case XADC_REG_VCCAUX:
945			case XADC_REG_VREFP:
946			case XADC_REG_VREFN:
947			case XADC_REG_VCCBRAM:
948			case XADC_REG_VCCPINT:
949			case XADC_REG_VCCPAUX:
950			case XADC_REG_VCCO_DDR:
951				*val = 3000;
952				break;
953			default:
954				*val = 1000;
955				break;
956			}
957			*val2 = bits;
958			return IIO_VAL_FRACTIONAL_LOG2;
959		case IIO_TEMP:
960			*val = xadc->ops->temp_scale;
961			*val2 = bits;
962			return IIO_VAL_FRACTIONAL_LOG2;
963		default:
964			return -EINVAL;
965		}
966	case IIO_CHAN_INFO_OFFSET:
967		/* Only the temperature channel has an offset */
968		*val = -((xadc->ops->temp_offset << bits) / xadc->ops->temp_scale);
969		return IIO_VAL_INT;
970	case IIO_CHAN_INFO_SAMP_FREQ:
971		ret = xadc_read_samplerate(xadc);
972		if (ret < 0)
973			return ret;
974
975		*val = ret;
976		return IIO_VAL_INT;
977	default:
978		return -EINVAL;
979	}
980}
981
982static int xadc_write_samplerate(struct xadc *xadc, int val)
983{
984	unsigned long clk_rate = xadc_get_dclk_rate(xadc);
985	unsigned int div;
986
987	if (!clk_rate)
988		return -EINVAL;
989
990	if (val <= 0)
991		return -EINVAL;
992
993	/* Max. 150 kSPS */
994	if (val > XADC_MAX_SAMPLERATE)
995		val = XADC_MAX_SAMPLERATE;
996
997	val *= 26;
998
999	/* Min 1MHz */
1000	if (val < 1000000)
1001		val = 1000000;
1002
1003	/*
1004	 * We want to round down, but only if we do not exceed the 150 kSPS
1005	 * limit.
1006	 */
1007	div = clk_rate / val;
1008	if (clk_rate / div / 26 > XADC_MAX_SAMPLERATE)
1009		div++;
1010	if (div < 2)
1011		div = 2;
1012	else if (div > 0xff)
1013		div = 0xff;
1014
1015	return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_DIV_MASK,
1016		div << XADC_CONF2_DIV_OFFSET);
1017}
1018
1019static int xadc_write_raw(struct iio_dev *indio_dev,
1020	struct iio_chan_spec const *chan, int val, int val2, long info)
1021{
1022	struct xadc *xadc = iio_priv(indio_dev);
1023
1024	if (info != IIO_CHAN_INFO_SAMP_FREQ)
1025		return -EINVAL;
1026
1027	return xadc_write_samplerate(xadc, val);
1028}
1029
1030static const struct iio_event_spec xadc_temp_events[] = {
1031	{
1032		.type = IIO_EV_TYPE_THRESH,
1033		.dir = IIO_EV_DIR_RISING,
1034		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
1035				BIT(IIO_EV_INFO_VALUE) |
1036				BIT(IIO_EV_INFO_HYSTERESIS),
1037	},
1038};
1039
1040/* Separate values for upper and lower thresholds, but only a shared enabled */
1041static const struct iio_event_spec xadc_voltage_events[] = {
1042	{
1043		.type = IIO_EV_TYPE_THRESH,
1044		.dir = IIO_EV_DIR_RISING,
1045		.mask_separate = BIT(IIO_EV_INFO_VALUE),
1046	}, {
1047		.type = IIO_EV_TYPE_THRESH,
1048		.dir = IIO_EV_DIR_FALLING,
1049		.mask_separate = BIT(IIO_EV_INFO_VALUE),
1050	}, {
1051		.type = IIO_EV_TYPE_THRESH,
1052		.dir = IIO_EV_DIR_EITHER,
1053		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
1054	},
1055};
1056
1057#define XADC_CHAN_TEMP(_chan, _scan_index, _addr, _bits) { \
1058	.type = IIO_TEMP, \
1059	.indexed = 1, \
1060	.channel = (_chan), \
1061	.address = (_addr), \
1062	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1063		BIT(IIO_CHAN_INFO_SCALE) | \
1064		BIT(IIO_CHAN_INFO_OFFSET), \
1065	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
1066	.event_spec = xadc_temp_events, \
1067	.num_event_specs = ARRAY_SIZE(xadc_temp_events), \
1068	.scan_index = (_scan_index), \
1069	.scan_type = { \
1070		.sign = 'u', \
1071		.realbits = (_bits), \
1072		.storagebits = 16, \
1073		.shift = 16 - (_bits), \
1074		.endianness = IIO_CPU, \
1075	}, \
1076}
1077
1078#define XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, _bits, _ext, _alarm) { \
1079	.type = IIO_VOLTAGE, \
1080	.indexed = 1, \
1081	.channel = (_chan), \
1082	.address = (_addr), \
1083	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
1084		BIT(IIO_CHAN_INFO_SCALE), \
1085	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
1086	.event_spec = (_alarm) ? xadc_voltage_events : NULL, \
1087	.num_event_specs = (_alarm) ? ARRAY_SIZE(xadc_voltage_events) : 0, \
1088	.scan_index = (_scan_index), \
1089	.scan_type = { \
1090		.sign = ((_addr) == XADC_REG_VREFN) ? 's' : 'u', \
1091		.realbits = (_bits), \
1092		.storagebits = 16, \
1093		.shift = 16 - (_bits), \
1094		.endianness = IIO_CPU, \
1095	}, \
1096	.extend_name = _ext, \
1097}
1098
1099/* 7 Series */
1100#define XADC_7S_CHAN_TEMP(_chan, _scan_index, _addr) \
1101	XADC_CHAN_TEMP(_chan, _scan_index, _addr, 12)
1102#define XADC_7S_CHAN_VOLTAGE(_chan, _scan_index, _addr, _ext, _alarm) \
1103	XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, 12, _ext, _alarm)
1104
1105static const struct iio_chan_spec xadc_7s_channels[] = {
1106	XADC_7S_CHAN_TEMP(0, 8, XADC_REG_TEMP),
1107	XADC_7S_CHAN_VOLTAGE(0, 9, XADC_REG_VCCINT, "vccint", true),
1108	XADC_7S_CHAN_VOLTAGE(1, 10, XADC_REG_VCCAUX, "vccaux", true),
1109	XADC_7S_CHAN_VOLTAGE(2, 14, XADC_REG_VCCBRAM, "vccbram", true),
1110	XADC_7S_CHAN_VOLTAGE(3, 5, XADC_REG_VCCPINT, "vccpint", true),
1111	XADC_7S_CHAN_VOLTAGE(4, 6, XADC_REG_VCCPAUX, "vccpaux", true),
1112	XADC_7S_CHAN_VOLTAGE(5, 7, XADC_REG_VCCO_DDR, "vccoddr", true),
1113	XADC_7S_CHAN_VOLTAGE(6, 12, XADC_REG_VREFP, "vrefp", false),
1114	XADC_7S_CHAN_VOLTAGE(7, 13, XADC_REG_VREFN, "vrefn", false),
1115	XADC_7S_CHAN_VOLTAGE(8, 11, XADC_REG_VPVN, NULL, false),
1116	XADC_7S_CHAN_VOLTAGE(9, 16, XADC_REG_VAUX(0), NULL, false),
1117	XADC_7S_CHAN_VOLTAGE(10, 17, XADC_REG_VAUX(1), NULL, false),
1118	XADC_7S_CHAN_VOLTAGE(11, 18, XADC_REG_VAUX(2), NULL, false),
1119	XADC_7S_CHAN_VOLTAGE(12, 19, XADC_REG_VAUX(3), NULL, false),
1120	XADC_7S_CHAN_VOLTAGE(13, 20, XADC_REG_VAUX(4), NULL, false),
1121	XADC_7S_CHAN_VOLTAGE(14, 21, XADC_REG_VAUX(5), NULL, false),
1122	XADC_7S_CHAN_VOLTAGE(15, 22, XADC_REG_VAUX(6), NULL, false),
1123	XADC_7S_CHAN_VOLTAGE(16, 23, XADC_REG_VAUX(7), NULL, false),
1124	XADC_7S_CHAN_VOLTAGE(17, 24, XADC_REG_VAUX(8), NULL, false),
1125	XADC_7S_CHAN_VOLTAGE(18, 25, XADC_REG_VAUX(9), NULL, false),
1126	XADC_7S_CHAN_VOLTAGE(19, 26, XADC_REG_VAUX(10), NULL, false),
1127	XADC_7S_CHAN_VOLTAGE(20, 27, XADC_REG_VAUX(11), NULL, false),
1128	XADC_7S_CHAN_VOLTAGE(21, 28, XADC_REG_VAUX(12), NULL, false),
1129	XADC_7S_CHAN_VOLTAGE(22, 29, XADC_REG_VAUX(13), NULL, false),
1130	XADC_7S_CHAN_VOLTAGE(23, 30, XADC_REG_VAUX(14), NULL, false),
1131	XADC_7S_CHAN_VOLTAGE(24, 31, XADC_REG_VAUX(15), NULL, false),
1132};
1133
1134/* UltraScale */
1135#define XADC_US_CHAN_TEMP(_chan, _scan_index, _addr) \
1136	XADC_CHAN_TEMP(_chan, _scan_index, _addr, 10)
1137#define XADC_US_CHAN_VOLTAGE(_chan, _scan_index, _addr, _ext, _alarm) \
1138	XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, 10, _ext, _alarm)
1139
1140static const struct iio_chan_spec xadc_us_channels[] = {
1141	XADC_US_CHAN_TEMP(0, 8, XADC_REG_TEMP),
1142	XADC_US_CHAN_VOLTAGE(0, 9, XADC_REG_VCCINT, "vccint", true),
1143	XADC_US_CHAN_VOLTAGE(1, 10, XADC_REG_VCCAUX, "vccaux", true),
1144	XADC_US_CHAN_VOLTAGE(2, 14, XADC_REG_VCCBRAM, "vccbram", true),
1145	XADC_US_CHAN_VOLTAGE(3, 5, XADC_REG_VCCPINT, "vccpsintlp", true),
1146	XADC_US_CHAN_VOLTAGE(4, 6, XADC_REG_VCCPAUX, "vccpsintfp", true),
1147	XADC_US_CHAN_VOLTAGE(5, 7, XADC_REG_VCCO_DDR, "vccpsaux", true),
1148	XADC_US_CHAN_VOLTAGE(6, 12, XADC_REG_VREFP, "vrefp", false),
1149	XADC_US_CHAN_VOLTAGE(7, 13, XADC_REG_VREFN, "vrefn", false),
1150	XADC_US_CHAN_VOLTAGE(8, 11, XADC_REG_VPVN, NULL, false),
1151	XADC_US_CHAN_VOLTAGE(9, 16, XADC_REG_VAUX(0), NULL, false),
1152	XADC_US_CHAN_VOLTAGE(10, 17, XADC_REG_VAUX(1), NULL, false),
1153	XADC_US_CHAN_VOLTAGE(11, 18, XADC_REG_VAUX(2), NULL, false),
1154	XADC_US_CHAN_VOLTAGE(12, 19, XADC_REG_VAUX(3), NULL, false),
1155	XADC_US_CHAN_VOLTAGE(13, 20, XADC_REG_VAUX(4), NULL, false),
1156	XADC_US_CHAN_VOLTAGE(14, 21, XADC_REG_VAUX(5), NULL, false),
1157	XADC_US_CHAN_VOLTAGE(15, 22, XADC_REG_VAUX(6), NULL, false),
1158	XADC_US_CHAN_VOLTAGE(16, 23, XADC_REG_VAUX(7), NULL, false),
1159	XADC_US_CHAN_VOLTAGE(17, 24, XADC_REG_VAUX(8), NULL, false),
1160	XADC_US_CHAN_VOLTAGE(18, 25, XADC_REG_VAUX(9), NULL, false),
1161	XADC_US_CHAN_VOLTAGE(19, 26, XADC_REG_VAUX(10), NULL, false),
1162	XADC_US_CHAN_VOLTAGE(20, 27, XADC_REG_VAUX(11), NULL, false),
1163	XADC_US_CHAN_VOLTAGE(21, 28, XADC_REG_VAUX(12), NULL, false),
1164	XADC_US_CHAN_VOLTAGE(22, 29, XADC_REG_VAUX(13), NULL, false),
1165	XADC_US_CHAN_VOLTAGE(23, 30, XADC_REG_VAUX(14), NULL, false),
1166	XADC_US_CHAN_VOLTAGE(24, 31, XADC_REG_VAUX(15), NULL, false),
1167};
1168
1169static const struct iio_info xadc_info = {
1170	.read_raw = &xadc_read_raw,
1171	.write_raw = &xadc_write_raw,
1172	.read_event_config = &xadc_read_event_config,
1173	.write_event_config = &xadc_write_event_config,
1174	.read_event_value = &xadc_read_event_value,
1175	.write_event_value = &xadc_write_event_value,
1176	.update_scan_mode = &xadc_update_scan_mode,
1177};
1178
1179static const struct of_device_id xadc_of_match_table[] = {
1180	{
1181		.compatible = "xlnx,zynq-xadc-1.00.a",
1182		.data = &xadc_zynq_ops
1183	}, {
1184		.compatible = "xlnx,axi-xadc-1.00.a",
1185		.data = &xadc_7s_axi_ops
1186	}, {
1187		.compatible = "xlnx,system-management-wiz-1.3",
1188		.data = &xadc_us_axi_ops
1189	},
1190	{ },
1191};
1192MODULE_DEVICE_TABLE(of, xadc_of_match_table);
1193
1194static int xadc_parse_dt(struct iio_dev *indio_dev, unsigned int *conf, int irq)
1195{
1196	struct device *dev = indio_dev->dev.parent;
1197	struct xadc *xadc = iio_priv(indio_dev);
1198	const struct iio_chan_spec *channel_templates;
1199	struct iio_chan_spec *channels, *chan;
1200	struct fwnode_handle *chan_node, *child;
1201	unsigned int max_channels;
1202	unsigned int num_channels;
1203	const char *external_mux;
1204	u32 ext_mux_chan;
1205	u32 reg;
1206	int ret;
1207	int i;
1208
1209	*conf = 0;
1210
1211	ret = device_property_read_string(dev, "xlnx,external-mux", &external_mux);
1212	if (ret < 0 || strcasecmp(external_mux, "none") == 0)
1213		xadc->external_mux_mode = XADC_EXTERNAL_MUX_NONE;
1214	else if (strcasecmp(external_mux, "single") == 0)
1215		xadc->external_mux_mode = XADC_EXTERNAL_MUX_SINGLE;
1216	else if (strcasecmp(external_mux, "dual") == 0)
1217		xadc->external_mux_mode = XADC_EXTERNAL_MUX_DUAL;
1218	else
1219		return -EINVAL;
1220
1221	if (xadc->external_mux_mode != XADC_EXTERNAL_MUX_NONE) {
1222		ret = device_property_read_u32(dev, "xlnx,external-mux-channel", &ext_mux_chan);
1223		if (ret < 0)
1224			return ret;
1225
1226		if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_SINGLE) {
1227			if (ext_mux_chan == 0)
1228				ext_mux_chan = XADC_REG_VPVN;
1229			else if (ext_mux_chan <= 16)
1230				ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1);
1231			else
1232				return -EINVAL;
1233		} else {
1234			if (ext_mux_chan > 0 && ext_mux_chan <= 8)
1235				ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1);
1236			else
1237				return -EINVAL;
1238		}
1239
1240		*conf |= XADC_CONF0_MUX | XADC_CONF0_CHAN(ext_mux_chan);
1241	}
1242	if (xadc->ops->type == XADC_TYPE_S7) {
1243		channel_templates = xadc_7s_channels;
1244		max_channels = ARRAY_SIZE(xadc_7s_channels);
1245	} else {
1246		channel_templates = xadc_us_channels;
1247		max_channels = ARRAY_SIZE(xadc_us_channels);
1248	}
1249	channels = devm_kmemdup(dev, channel_templates,
1250				sizeof(channels[0]) * max_channels, GFP_KERNEL);
1251	if (!channels)
1252		return -ENOMEM;
1253
1254	num_channels = 9;
1255	chan = &channels[9];
1256
1257	chan_node = device_get_named_child_node(dev, "xlnx,channels");
1258	fwnode_for_each_child_node(chan_node, child) {
1259		if (num_channels >= max_channels) {
1260			fwnode_handle_put(child);
1261			break;
1262		}
1263
1264		ret = fwnode_property_read_u32(child, "reg", &reg);
1265		if (ret || reg > 16)
1266			continue;
1267
1268		if (fwnode_property_read_bool(child, "xlnx,bipolar"))
1269			chan->scan_type.sign = 's';
1270
1271		if (reg == 0) {
1272			chan->scan_index = 11;
1273			chan->address = XADC_REG_VPVN;
1274		} else {
1275			chan->scan_index = 15 + reg;
1276			chan->address = XADC_REG_VAUX(reg - 1);
1277		}
1278		num_channels++;
1279		chan++;
1280	}
1281	fwnode_handle_put(chan_node);
1282
1283	/* No IRQ => no events */
1284	if (irq <= 0) {
1285		for (i = 0; i < num_channels; i++) {
1286			channels[i].event_spec = NULL;
1287			channels[i].num_event_specs = 0;
1288		}
1289	}
1290
1291	indio_dev->num_channels = num_channels;
1292	indio_dev->channels = devm_krealloc_array(dev, channels,
1293						  num_channels, sizeof(*channels),
1294						  GFP_KERNEL);
1295	/* If we can't resize the channels array, just use the original */
1296	if (!indio_dev->channels)
1297		indio_dev->channels = channels;
1298
1299	return 0;
1300}
1301
1302static const char * const xadc_type_names[] = {
1303	[XADC_TYPE_S7] = "xadc",
1304	[XADC_TYPE_US] = "xilinx-system-monitor",
1305};
1306
1307static void xadc_cancel_delayed_work(void *data)
1308{
1309	struct delayed_work *work = data;
1310
1311	cancel_delayed_work_sync(work);
1312}
1313
1314static int xadc_probe(struct platform_device *pdev)
1315{
1316	struct device *dev = &pdev->dev;
1317	const struct xadc_ops *ops;
1318	struct iio_dev *indio_dev;
1319	unsigned int bipolar_mask;
1320	unsigned int conf0;
1321	struct xadc *xadc;
1322	int ret;
1323	int irq;
1324	int i;
1325
1326	ops = device_get_match_data(dev);
1327	if (!ops)
1328		return -EINVAL;
1329
1330	irq = platform_get_irq_optional(pdev, 0);
1331	if (irq < 0 &&
1332	    (irq != -ENXIO || !(ops->flags & XADC_FLAGS_IRQ_OPTIONAL)))
1333		return irq;
1334
1335	indio_dev = devm_iio_device_alloc(dev, sizeof(*xadc));
1336	if (!indio_dev)
1337		return -ENOMEM;
1338
1339	xadc = iio_priv(indio_dev);
1340	xadc->ops = ops;
1341	init_completion(&xadc->completion);
1342	mutex_init(&xadc->mutex);
1343	spin_lock_init(&xadc->lock);
1344	INIT_DELAYED_WORK(&xadc->zynq_unmask_work, xadc_zynq_unmask_worker);
1345
1346	xadc->base = devm_platform_ioremap_resource(pdev, 0);
1347	if (IS_ERR(xadc->base))
1348		return PTR_ERR(xadc->base);
1349
1350	indio_dev->name = xadc_type_names[xadc->ops->type];
1351	indio_dev->modes = INDIO_DIRECT_MODE;
1352	indio_dev->info = &xadc_info;
1353
1354	ret = xadc_parse_dt(indio_dev, &conf0, irq);
1355	if (ret)
1356		return ret;
1357
1358	if (xadc->ops->flags & XADC_FLAGS_BUFFERED) {
1359		ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
1360						      &iio_pollfunc_store_time,
1361						      &xadc_trigger_handler,
1362						      &xadc_buffer_ops);
1363		if (ret)
1364			return ret;
1365
1366		if (irq > 0) {
1367			xadc->convst_trigger = xadc_alloc_trigger(indio_dev, "convst");
1368			if (IS_ERR(xadc->convst_trigger))
1369				return PTR_ERR(xadc->convst_trigger);
1370
1371			xadc->samplerate_trigger = xadc_alloc_trigger(indio_dev,
1372				"samplerate");
1373			if (IS_ERR(xadc->samplerate_trigger))
1374				return PTR_ERR(xadc->samplerate_trigger);
1375		}
1376	}
1377
1378	xadc->clk = devm_clk_get_enabled(dev, NULL);
1379	if (IS_ERR(xadc->clk))
1380		return PTR_ERR(xadc->clk);
1381
1382	/*
1383	 * Make sure not to exceed the maximum samplerate since otherwise the
1384	 * resulting interrupt storm will soft-lock the system.
1385	 */
1386	if (xadc->ops->flags & XADC_FLAGS_BUFFERED) {
1387		ret = xadc_read_samplerate(xadc);
1388		if (ret < 0)
1389			return ret;
1390
1391		if (ret > XADC_MAX_SAMPLERATE) {
1392			ret = xadc_write_samplerate(xadc, XADC_MAX_SAMPLERATE);
1393			if (ret < 0)
1394				return ret;
1395		}
1396	}
1397
1398	if (irq > 0) {
1399		ret = devm_request_irq(dev, irq, xadc->ops->interrupt_handler,
1400				       0, dev_name(dev), indio_dev);
1401		if (ret)
1402			return ret;
1403
1404		ret = devm_add_action_or_reset(dev, xadc_cancel_delayed_work,
1405					       &xadc->zynq_unmask_work);
1406		if (ret)
1407			return ret;
1408	}
1409
1410	ret = xadc->ops->setup(pdev, indio_dev, irq);
1411	if (ret)
1412		return ret;
1413
1414	for (i = 0; i < 16; i++)
1415		xadc_read_adc_reg(xadc, XADC_REG_THRESHOLD(i),
1416			&xadc->threshold[i]);
1417
1418	ret = xadc_write_adc_reg(xadc, XADC_REG_CONF0, conf0);
1419	if (ret)
1420		return ret;
1421
1422	bipolar_mask = 0;
1423	for (i = 0; i < indio_dev->num_channels; i++) {
1424		if (indio_dev->channels[i].scan_type.sign == 's')
1425			bipolar_mask |= BIT(indio_dev->channels[i].scan_index);
1426	}
1427
1428	ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(0), bipolar_mask);
1429	if (ret)
1430		return ret;
1431
1432	ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(1),
1433		bipolar_mask >> 16);
1434	if (ret)
1435		return ret;
1436
1437	/* Go to non-buffered mode */
1438	xadc_postdisable(indio_dev);
1439
1440	return devm_iio_device_register(dev, indio_dev);
1441}
1442
1443static struct platform_driver xadc_driver = {
1444	.probe = xadc_probe,
1445	.driver = {
1446		.name = "xadc",
1447		.of_match_table = xadc_of_match_table,
1448	},
1449};
1450module_platform_driver(xadc_driver);
1451
1452MODULE_LICENSE("GPL v2");
1453MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
1454MODULE_DESCRIPTION("Xilinx XADC IIO driver");
1455