2 * Atmel ADC driver for SAMA5D2 devices and compatible.
4 * Copyright (C) 2015 Atmel,
5 * 2015 Ludovic Desroches <ludovic.desroches@atmel.com>
7 * This software is licensed under the terms of the GNU General Public
8 * License version 2, as published by the Free Software Foundation, and
9 * may be copied, distributed, and modified under those terms.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
17 #include <linux/bitops.h>
18 #include <linux/clk.h>
19 #include <linux/interrupt.h>
21 #include <linux/module.h>
22 #include <linux/of_device.h>
23 #include <linux/platform_device.h>
24 #include <linux/sched.h>
25 #include <linux/wait.h>
26 #include <linux/iio/iio.h>
27 #include <linux/iio/sysfs.h>
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/trigger.h>
30 #include <linux/iio/trigger_consumer.h>
31 #include <linux/iio/triggered_buffer.h>
32 #include <linux/pinctrl/consumer.h>
33 #include <linux/regulator/consumer.h>
35 /* Control Register */
36 #define AT91_SAMA5D2_CR 0x00
38 #define AT91_SAMA5D2_CR_SWRST BIT(0)
39 /* Start Conversion */
40 #define AT91_SAMA5D2_CR_START BIT(1)
41 /* Touchscreen Calibration */
42 #define AT91_SAMA5D2_CR_TSCALIB BIT(2)
43 /* Comparison Restart */
44 #define AT91_SAMA5D2_CR_CMPRST BIT(4)
47 #define AT91_SAMA5D2_MR 0x04
48 /* Trigger Selection */
49 #define AT91_SAMA5D2_MR_TRGSEL(v) ((v) << 1)
51 #define AT91_SAMA5D2_MR_TRGSEL_TRIG0 0
53 #define AT91_SAMA5D2_MR_TRGSEL_TRIG1 1
55 #define AT91_SAMA5D2_MR_TRGSEL_TRIG2 2
57 #define AT91_SAMA5D2_MR_TRGSEL_TRIG3 3
58 /* PWM event line 0 */
59 #define AT91_SAMA5D2_MR_TRGSEL_TRIG4 4
60 /* PWM event line 1 */
61 #define AT91_SAMA5D2_MR_TRGSEL_TRIG5 5
63 #define AT91_SAMA5D2_MR_TRGSEL_TRIG6 6
65 #define AT91_SAMA5D2_MR_TRGSEL_TRIG7 7
67 #define AT91_SAMA5D2_MR_SLEEP BIT(5)
69 #define AT91_SAMA5D2_MR_FWUP BIT(6)
70 /* Prescaler Rate Selection */
71 #define AT91_SAMA5D2_MR_PRESCAL(v) ((v) << AT91_SAMA5D2_MR_PRESCAL_OFFSET)
72 #define AT91_SAMA5D2_MR_PRESCAL_OFFSET 8
73 #define AT91_SAMA5D2_MR_PRESCAL_MAX 0xff
74 #define AT91_SAMA5D2_MR_PRESCAL_MASK GENMASK(15, 8)
76 #define AT91_SAMA5D2_MR_STARTUP(v) ((v) << 16)
77 #define AT91_SAMA5D2_MR_STARTUP_MASK GENMASK(19, 16)
79 #define AT91_SAMA5D2_MR_ANACH BIT(23)
81 #define AT91_SAMA5D2_MR_TRACKTIM(v) ((v) << 24)
82 #define AT91_SAMA5D2_MR_TRACKTIM_MAX 0xff
84 #define AT91_SAMA5D2_MR_TRANSFER(v) ((v) << 28)
85 #define AT91_SAMA5D2_MR_TRANSFER_MAX 0x3
86 /* Use Sequence Enable */
87 #define AT91_SAMA5D2_MR_USEQ BIT(31)
89 /* Channel Sequence Register 1 */
90 #define AT91_SAMA5D2_SEQR1 0x08
91 /* Channel Sequence Register 2 */
92 #define AT91_SAMA5D2_SEQR2 0x0c
93 /* Channel Enable Register */
94 #define AT91_SAMA5D2_CHER 0x10
95 /* Channel Disable Register */
96 #define AT91_SAMA5D2_CHDR 0x14
97 /* Channel Status Register */
98 #define AT91_SAMA5D2_CHSR 0x18
99 /* Last Converted Data Register */
100 #define AT91_SAMA5D2_LCDR 0x20
101 /* Interrupt Enable Register */
102 #define AT91_SAMA5D2_IER 0x24
103 /* Interrupt Disable Register */
104 #define AT91_SAMA5D2_IDR 0x28
105 /* Interrupt Mask Register */
106 #define AT91_SAMA5D2_IMR 0x2c
107 /* Interrupt Status Register */
108 #define AT91_SAMA5D2_ISR 0x30
109 /* Last Channel Trigger Mode Register */
110 #define AT91_SAMA5D2_LCTMR 0x34
111 /* Last Channel Compare Window Register */
112 #define AT91_SAMA5D2_LCCWR 0x38
113 /* Overrun Status Register */
114 #define AT91_SAMA5D2_OVER 0x3c
115 /* Extended Mode Register */
116 #define AT91_SAMA5D2_EMR 0x40
117 /* Compare Window Register */
118 #define AT91_SAMA5D2_CWR 0x44
119 /* Channel Gain Register */
120 #define AT91_SAMA5D2_CGR 0x48
122 /* Channel Offset Register */
123 #define AT91_SAMA5D2_COR 0x4c
124 #define AT91_SAMA5D2_COR_DIFF_OFFSET 16
126 /* Channel Data Register 0 */
127 #define AT91_SAMA5D2_CDR0 0x50
128 /* Analog Control Register */
129 #define AT91_SAMA5D2_ACR 0x94
130 /* Touchscreen Mode Register */
131 #define AT91_SAMA5D2_TSMR 0xb0
132 /* Touchscreen X Position Register */
133 #define AT91_SAMA5D2_XPOSR 0xb4
134 /* Touchscreen Y Position Register */
135 #define AT91_SAMA5D2_YPOSR 0xb8
136 /* Touchscreen Pressure Register */
137 #define AT91_SAMA5D2_PRESSR 0xbc
138 /* Trigger Register */
139 #define AT91_SAMA5D2_TRGR 0xc0
140 /* Mask for TRGMOD field of TRGR register */
141 #define AT91_SAMA5D2_TRGR_TRGMOD_MASK GENMASK(2, 0)
142 /* No trigger, only software trigger can start conversions */
143 #define AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER 0
144 /* Trigger Mode external trigger rising edge */
145 #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE 1
146 /* Trigger Mode external trigger falling edge */
147 #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL 2
148 /* Trigger Mode external trigger any edge */
149 #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY 3
151 /* Correction Select Register */
152 #define AT91_SAMA5D2_COSR 0xd0
153 /* Correction Value Register */
154 #define AT91_SAMA5D2_CVR 0xd4
155 /* Channel Error Correction Register */
156 #define AT91_SAMA5D2_CECR 0xd8
157 /* Write Protection Mode Register */
158 #define AT91_SAMA5D2_WPMR 0xe4
159 /* Write Protection Status Register */
160 #define AT91_SAMA5D2_WPSR 0xe8
161 /* Version Register */
162 #define AT91_SAMA5D2_VERSION 0xfc
164 #define AT91_SAMA5D2_HW_TRIG_CNT 3
165 #define AT91_SAMA5D2_SINGLE_CHAN_CNT 12
166 #define AT91_SAMA5D2_DIFF_CHAN_CNT 6
169 * Maximum number of bytes to hold conversion from all channels
172 #define AT91_BUFFER_MAX_BYTES ((AT91_SAMA5D2_SINGLE_CHAN_CNT + \
173 AT91_SAMA5D2_DIFF_CHAN_CNT) * 2 + 8)
175 #define AT91_BUFFER_MAX_HWORDS (AT91_BUFFER_MAX_BYTES / 2)
177 #define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \
179 .type = IIO_VOLTAGE, \
188 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
189 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
190 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
191 .datasheet_name = "CH"#num, \
195 #define AT91_SAMA5D2_CHAN_DIFF(num, num2, addr) \
197 .type = IIO_VOLTAGE, \
202 .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \
208 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
209 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
210 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
211 .datasheet_name = "CH"#num"-CH"#num2, \
215 #define at91_adc_readl(st, reg) readl_relaxed(st->base + reg)
216 #define at91_adc_writel(st, reg, val) writel_relaxed(val, st->base + reg)
218 struct at91_adc_soc_info {
219 unsigned startup_time;
220 unsigned min_sample_rate;
221 unsigned max_sample_rate;
224 struct at91_adc_trigger {
226 unsigned int trgmod_value;
227 unsigned int edge_type;
230 struct at91_adc_state {
234 struct regulator *reg;
235 struct regulator *vref;
237 struct iio_trigger *trig;
238 const struct at91_adc_trigger *selected_trig;
239 const struct iio_chan_spec *chan;
240 bool conversion_done;
241 u32 conversion_value;
242 struct at91_adc_soc_info soc_info;
243 wait_queue_head_t wq_data_available;
244 u16 buffer[AT91_BUFFER_MAX_HWORDS];
246 * lock to prevent concurrent 'single conversion' requests through
252 static const struct at91_adc_trigger at91_adc_trigger_list[] = {
254 .name = "external_rising",
255 .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE,
256 .edge_type = IRQ_TYPE_EDGE_RISING,
259 .name = "external_falling",
260 .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL,
261 .edge_type = IRQ_TYPE_EDGE_FALLING,
264 .name = "external_any",
265 .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY,
266 .edge_type = IRQ_TYPE_EDGE_BOTH,
270 static const struct iio_chan_spec at91_adc_channels[] = {
271 AT91_SAMA5D2_CHAN_SINGLE(0, 0x50),
272 AT91_SAMA5D2_CHAN_SINGLE(1, 0x54),
273 AT91_SAMA5D2_CHAN_SINGLE(2, 0x58),
274 AT91_SAMA5D2_CHAN_SINGLE(3, 0x5c),
275 AT91_SAMA5D2_CHAN_SINGLE(4, 0x60),
276 AT91_SAMA5D2_CHAN_SINGLE(5, 0x64),
277 AT91_SAMA5D2_CHAN_SINGLE(6, 0x68),
278 AT91_SAMA5D2_CHAN_SINGLE(7, 0x6c),
279 AT91_SAMA5D2_CHAN_SINGLE(8, 0x70),
280 AT91_SAMA5D2_CHAN_SINGLE(9, 0x74),
281 AT91_SAMA5D2_CHAN_SINGLE(10, 0x78),
282 AT91_SAMA5D2_CHAN_SINGLE(11, 0x7c),
283 AT91_SAMA5D2_CHAN_DIFF(0, 1, 0x50),
284 AT91_SAMA5D2_CHAN_DIFF(2, 3, 0x58),
285 AT91_SAMA5D2_CHAN_DIFF(4, 5, 0x60),
286 AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68),
287 AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70),
288 AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78),
289 IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_SINGLE_CHAN_CNT
290 + AT91_SAMA5D2_DIFF_CHAN_CNT + 1),
293 static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
295 struct iio_dev *indio = iio_trigger_get_drvdata(trig);
296 struct at91_adc_state *st = iio_priv(indio);
297 u32 status = at91_adc_readl(st, AT91_SAMA5D2_TRGR);
301 status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK;
304 status |= st->selected_trig->trgmod_value;
306 /* set/unset hw trigger */
307 at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
309 for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
310 struct iio_chan_spec const *chan = indio->channels + bit;
313 at91_adc_writel(st, AT91_SAMA5D2_CHER,
315 at91_adc_writel(st, AT91_SAMA5D2_IER,
318 at91_adc_writel(st, AT91_SAMA5D2_IDR,
320 at91_adc_writel(st, AT91_SAMA5D2_CHDR,
328 static int at91_adc_reenable_trigger(struct iio_trigger *trig)
330 struct iio_dev *indio = iio_trigger_get_drvdata(trig);
331 struct at91_adc_state *st = iio_priv(indio);
335 /* Needed to ACK the DRDY interruption */
336 at91_adc_readl(st, AT91_SAMA5D2_LCDR);
340 static const struct iio_trigger_ops at91_adc_trigger_ops = {
341 .owner = THIS_MODULE,
342 .set_trigger_state = &at91_adc_configure_trigger,
343 .try_reenable = &at91_adc_reenable_trigger,
346 static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *indio,
349 struct iio_trigger *trig;
352 trig = devm_iio_trigger_alloc(&indio->dev, "%s-dev%d-%s", indio->name,
353 indio->id, trigger_name);
357 trig->dev.parent = indio->dev.parent;
358 iio_trigger_set_drvdata(trig, indio);
359 trig->ops = &at91_adc_trigger_ops;
361 ret = devm_iio_trigger_register(&indio->dev, trig);
368 static int at91_adc_trigger_init(struct iio_dev *indio)
370 struct at91_adc_state *st = iio_priv(indio);
372 st->trig = at91_adc_allocate_trigger(indio, st->selected_trig->name);
373 if (IS_ERR(st->trig)) {
375 "could not allocate trigger\n");
376 return PTR_ERR(st->trig);
382 static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
384 struct iio_poll_func *pf = p;
385 struct iio_dev *indio = pf->indio_dev;
386 struct at91_adc_state *st = iio_priv(indio);
390 for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
391 struct iio_chan_spec const *chan = indio->channels + bit;
393 st->buffer[i] = at91_adc_readl(st, chan->address);
397 iio_push_to_buffers_with_timestamp(indio, st->buffer, pf->timestamp);
399 iio_trigger_notify_done(indio->trig);
404 static int at91_adc_buffer_init(struct iio_dev *indio)
406 return devm_iio_triggered_buffer_setup(&indio->dev, indio,
407 &iio_pollfunc_store_time,
408 &at91_adc_trigger_handler, NULL);
411 static unsigned at91_adc_startup_time(unsigned startup_time_min,
412 unsigned adc_clk_khz)
414 static const unsigned int startup_lookup[] = {
420 unsigned ticks_min, i;
423 * Since the adc frequency is checked before, there is no reason
424 * to not meet the startup time constraint.
427 ticks_min = startup_time_min * adc_clk_khz / 1000;
428 for (i = 0; i < ARRAY_SIZE(startup_lookup); i++)
429 if (startup_lookup[i] > ticks_min)
435 static void at91_adc_setup_samp_freq(struct at91_adc_state *st, unsigned freq)
437 struct iio_dev *indio_dev = iio_priv_to_dev(st);
438 unsigned f_per, prescal, startup, mr;
440 f_per = clk_get_rate(st->per_clk);
441 prescal = (f_per / (2 * freq)) - 1;
443 startup = at91_adc_startup_time(st->soc_info.startup_time,
446 mr = at91_adc_readl(st, AT91_SAMA5D2_MR);
447 mr &= ~(AT91_SAMA5D2_MR_STARTUP_MASK | AT91_SAMA5D2_MR_PRESCAL_MASK);
448 mr |= AT91_SAMA5D2_MR_STARTUP(startup);
449 mr |= AT91_SAMA5D2_MR_PRESCAL(prescal);
450 at91_adc_writel(st, AT91_SAMA5D2_MR, mr);
452 dev_dbg(&indio_dev->dev, "freq: %u, startup: %u, prescal: %u\n",
453 freq, startup, prescal);
456 static unsigned at91_adc_get_sample_freq(struct at91_adc_state *st)
458 unsigned f_adc, f_per = clk_get_rate(st->per_clk);
459 unsigned mr, prescal;
461 mr = at91_adc_readl(st, AT91_SAMA5D2_MR);
462 prescal = (mr >> AT91_SAMA5D2_MR_PRESCAL_OFFSET)
463 & AT91_SAMA5D2_MR_PRESCAL_MAX;
464 f_adc = f_per / (2 * (prescal + 1));
469 static irqreturn_t at91_adc_interrupt(int irq, void *private)
471 struct iio_dev *indio = private;
472 struct at91_adc_state *st = iio_priv(indio);
473 u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR);
474 u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR);
479 if (iio_buffer_enabled(indio)) {
480 disable_irq_nosync(irq);
481 iio_trigger_poll(indio->trig);
483 st->conversion_value = at91_adc_readl(st, st->chan->address);
484 st->conversion_done = true;
485 wake_up_interruptible(&st->wq_data_available);
490 static int at91_adc_read_raw(struct iio_dev *indio_dev,
491 struct iio_chan_spec const *chan,
492 int *val, int *val2, long mask)
494 struct at91_adc_state *st = iio_priv(indio_dev);
499 case IIO_CHAN_INFO_RAW:
500 /* we cannot use software trigger if hw trigger enabled */
501 ret = iio_device_claim_direct_mode(indio_dev);
505 mutex_lock(&st->lock);
509 if (chan->differential)
510 cor = (BIT(chan->channel) | BIT(chan->channel2)) <<
511 AT91_SAMA5D2_COR_DIFF_OFFSET;
513 at91_adc_writel(st, AT91_SAMA5D2_COR, cor);
514 at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel));
515 at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel));
516 at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START);
518 ret = wait_event_interruptible_timeout(st->wq_data_available,
520 msecs_to_jiffies(1000));
525 *val = st->conversion_value;
526 if (chan->scan_type.sign == 's')
527 *val = sign_extend32(*val, 11);
529 st->conversion_done = false;
532 at91_adc_writel(st, AT91_SAMA5D2_IDR, BIT(chan->channel));
533 at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel));
535 mutex_unlock(&st->lock);
537 iio_device_release_direct_mode(indio_dev);
540 case IIO_CHAN_INFO_SCALE:
541 *val = st->vref_uv / 1000;
542 if (chan->differential)
544 *val2 = chan->scan_type.realbits;
545 return IIO_VAL_FRACTIONAL_LOG2;
547 case IIO_CHAN_INFO_SAMP_FREQ:
548 *val = at91_adc_get_sample_freq(st);
556 static int at91_adc_write_raw(struct iio_dev *indio_dev,
557 struct iio_chan_spec const *chan,
558 int val, int val2, long mask)
560 struct at91_adc_state *st = iio_priv(indio_dev);
562 if (mask != IIO_CHAN_INFO_SAMP_FREQ)
565 if (val < st->soc_info.min_sample_rate ||
566 val > st->soc_info.max_sample_rate)
569 at91_adc_setup_samp_freq(st, val);
574 static const struct iio_info at91_adc_info = {
575 .read_raw = &at91_adc_read_raw,
576 .write_raw = &at91_adc_write_raw,
577 .driver_module = THIS_MODULE,
580 static void at91_adc_hw_init(struct at91_adc_state *st)
582 at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_SWRST);
583 at91_adc_writel(st, AT91_SAMA5D2_IDR, 0xffffffff);
585 * Transfer field must be set to 2 according to the datasheet and
586 * allows different analog settings for each channel.
588 at91_adc_writel(st, AT91_SAMA5D2_MR,
589 AT91_SAMA5D2_MR_TRANSFER(2) | AT91_SAMA5D2_MR_ANACH);
591 at91_adc_setup_samp_freq(st, st->soc_info.min_sample_rate);
594 static int at91_adc_probe(struct platform_device *pdev)
596 struct iio_dev *indio_dev;
597 struct at91_adc_state *st;
598 struct resource *res;
602 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st));
606 indio_dev->dev.parent = &pdev->dev;
607 indio_dev->name = dev_name(&pdev->dev);
608 indio_dev->modes = INDIO_DIRECT_MODE;
609 indio_dev->info = &at91_adc_info;
610 indio_dev->channels = at91_adc_channels;
611 indio_dev->num_channels = ARRAY_SIZE(at91_adc_channels);
613 st = iio_priv(indio_dev);
615 ret = of_property_read_u32(pdev->dev.of_node,
616 "atmel,min-sample-rate-hz",
617 &st->soc_info.min_sample_rate);
620 "invalid or missing value for atmel,min-sample-rate-hz\n");
624 ret = of_property_read_u32(pdev->dev.of_node,
625 "atmel,max-sample-rate-hz",
626 &st->soc_info.max_sample_rate);
629 "invalid or missing value for atmel,max-sample-rate-hz\n");
633 ret = of_property_read_u32(pdev->dev.of_node, "atmel,startup-time-ms",
634 &st->soc_info.startup_time);
637 "invalid or missing value for atmel,startup-time-ms\n");
641 ret = of_property_read_u32(pdev->dev.of_node,
642 "atmel,trigger-edge-type", &edge_type);
645 "invalid or missing value for atmel,trigger-edge-type\n");
649 st->selected_trig = NULL;
651 for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT; i++)
652 if (at91_adc_trigger_list[i].edge_type == edge_type) {
653 st->selected_trig = &at91_adc_trigger_list[i];
657 if (!st->selected_trig) {
658 dev_err(&pdev->dev, "invalid external trigger edge value\n");
662 init_waitqueue_head(&st->wq_data_available);
663 mutex_init(&st->lock);
665 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
669 st->base = devm_ioremap_resource(&pdev->dev, res);
670 if (IS_ERR(st->base))
671 return PTR_ERR(st->base);
673 st->irq = platform_get_irq(pdev, 0);
681 st->per_clk = devm_clk_get(&pdev->dev, "adc_clk");
682 if (IS_ERR(st->per_clk))
683 return PTR_ERR(st->per_clk);
685 st->reg = devm_regulator_get(&pdev->dev, "vddana");
687 return PTR_ERR(st->reg);
689 st->vref = devm_regulator_get(&pdev->dev, "vref");
690 if (IS_ERR(st->vref))
691 return PTR_ERR(st->vref);
693 ret = devm_request_irq(&pdev->dev, st->irq, at91_adc_interrupt, 0,
694 pdev->dev.driver->name, indio_dev);
698 ret = regulator_enable(st->reg);
702 ret = regulator_enable(st->vref);
706 st->vref_uv = regulator_get_voltage(st->vref);
707 if (st->vref_uv <= 0) {
712 at91_adc_hw_init(st);
714 ret = clk_prepare_enable(st->per_clk);
718 platform_set_drvdata(pdev, indio_dev);
720 ret = at91_adc_buffer_init(indio_dev);
722 dev_err(&pdev->dev, "couldn't initialize the buffer.\n");
723 goto per_clk_disable_unprepare;
726 ret = at91_adc_trigger_init(indio_dev);
728 dev_err(&pdev->dev, "couldn't setup the triggers.\n");
729 goto per_clk_disable_unprepare;
732 ret = iio_device_register(indio_dev);
734 goto per_clk_disable_unprepare;
736 dev_info(&pdev->dev, "setting up trigger as %s\n",
737 st->selected_trig->name);
739 dev_info(&pdev->dev, "version: %x\n",
740 readl_relaxed(st->base + AT91_SAMA5D2_VERSION));
744 per_clk_disable_unprepare:
745 clk_disable_unprepare(st->per_clk);
747 regulator_disable(st->vref);
749 regulator_disable(st->reg);
753 static int at91_adc_remove(struct platform_device *pdev)
755 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
756 struct at91_adc_state *st = iio_priv(indio_dev);
758 iio_device_unregister(indio_dev);
760 clk_disable_unprepare(st->per_clk);
762 regulator_disable(st->vref);
763 regulator_disable(st->reg);
768 static __maybe_unused int at91_adc_suspend(struct device *dev)
770 struct iio_dev *indio_dev =
771 platform_get_drvdata(to_platform_device(dev));
772 struct at91_adc_state *st = iio_priv(indio_dev);
775 * Do a sofware reset of the ADC before we go to suspend.
776 * this will ensure that all pins are free from being muxed by the ADC
777 * and can be used by for other devices.
778 * Otherwise, ADC will hog them and we can't go to suspend mode.
780 at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_SWRST);
782 clk_disable_unprepare(st->per_clk);
783 regulator_disable(st->vref);
784 regulator_disable(st->reg);
786 return pinctrl_pm_select_sleep_state(dev);
789 static __maybe_unused int at91_adc_resume(struct device *dev)
791 struct iio_dev *indio_dev =
792 platform_get_drvdata(to_platform_device(dev));
793 struct at91_adc_state *st = iio_priv(indio_dev);
796 ret = pinctrl_pm_select_default_state(dev);
800 ret = regulator_enable(st->reg);
804 ret = regulator_enable(st->vref);
806 goto reg_disable_resume;
808 ret = clk_prepare_enable(st->per_clk);
810 goto vref_disable_resume;
812 at91_adc_hw_init(st);
814 /* reconfiguring trigger hardware state */
815 if (iio_buffer_enabled(indio_dev))
816 at91_adc_configure_trigger(st->trig, true);
821 regulator_disable(st->vref);
823 regulator_disable(st->reg);
825 dev_err(&indio_dev->dev, "failed to resume\n");
829 static SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend, at91_adc_resume);
831 static const struct of_device_id at91_adc_dt_match[] = {
833 .compatible = "atmel,sama5d2-adc",
838 MODULE_DEVICE_TABLE(of, at91_adc_dt_match);
840 static struct platform_driver at91_adc_driver = {
841 .probe = at91_adc_probe,
842 .remove = at91_adc_remove,
844 .name = "at91-sama5d2_adc",
845 .of_match_table = at91_adc_dt_match,
846 .pm = &at91_adc_pm_ops,
849 module_platform_driver(at91_adc_driver)
851 MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
852 MODULE_DESCRIPTION("Atmel AT91 SAMA5D2 ADC");
853 MODULE_LICENSE("GPL v2");