Linux-libre 4.19.123-gnu
[librecmc/linux-libre.git] / drivers / iio / adc / sun4i-gpadc-iio.c
1 /* ADC driver for sunxi platforms' (A10, A13 and A31) GPADC
2  *
3  * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it under
6  * the terms of the GNU General Public License version 2 as published by the
7  * Free Software Foundation.
8  *
9  * The Allwinner SoCs all have an ADC that can also act as a touchscreen
10  * controller and a thermal sensor.
11  * The thermal sensor works only when the ADC acts as a touchscreen controller
12  * and is configured to throw an interrupt every fixed periods of time (let say
13  * every X seconds).
14  * One would be tempted to disable the IP on the hardware side rather than
15  * disabling interrupts to save some power but that resets the internal clock of
16  * the IP, resulting in having to wait X seconds every time we want to read the
17  * value of the thermal sensor.
18  * This is also the reason of using autosuspend in pm_runtime. If there was no
19  * autosuspend, the thermal sensor would need X seconds after every
20  * pm_runtime_get_sync to get a value from the ADC. The autosuspend allows the
21  * thermal sensor to be requested again in a certain time span before it gets
22  * shutdown for not being used.
23  */
24
25 #include <linux/completion.h>
26 #include <linux/interrupt.h>
27 #include <linux/io.h>
28 #include <linux/module.h>
29 #include <linux/of.h>
30 #include <linux/of_device.h>
31 #include <linux/platform_device.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/regmap.h>
34 #include <linux/thermal.h>
35 #include <linux/delay.h>
36
37 #include <linux/iio/iio.h>
38 #include <linux/iio/driver.h>
39 #include <linux/iio/machine.h>
40 #include <linux/mfd/sun4i-gpadc.h>
41
42 static unsigned int sun4i_gpadc_chan_select(unsigned int chan)
43 {
44         return SUN4I_GPADC_CTRL1_ADC_CHAN_SELECT(chan);
45 }
46
47 static unsigned int sun6i_gpadc_chan_select(unsigned int chan)
48 {
49         return SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(chan);
50 }
51
52 struct gpadc_data {
53         int             temp_offset;
54         int             temp_scale;
55         unsigned int    tp_mode_en;
56         unsigned int    tp_adc_select;
57         unsigned int    (*adc_chan_select)(unsigned int chan);
58         unsigned int    adc_chan_mask;
59 };
60
61 static const struct gpadc_data sun4i_gpadc_data = {
62         .temp_offset = -1932,
63         .temp_scale = 133,
64         .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN,
65         .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
66         .adc_chan_select = &sun4i_gpadc_chan_select,
67         .adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
68 };
69
70 static const struct gpadc_data sun5i_gpadc_data = {
71         .temp_offset = -1447,
72         .temp_scale = 100,
73         .tp_mode_en = SUN4I_GPADC_CTRL1_TP_MODE_EN,
74         .tp_adc_select = SUN4I_GPADC_CTRL1_TP_ADC_SELECT,
75         .adc_chan_select = &sun4i_gpadc_chan_select,
76         .adc_chan_mask = SUN4I_GPADC_CTRL1_ADC_CHAN_MASK,
77 };
78
79 static const struct gpadc_data sun6i_gpadc_data = {
80         .temp_offset = -1623,
81         .temp_scale = 167,
82         .tp_mode_en = SUN6I_GPADC_CTRL1_TP_MODE_EN,
83         .tp_adc_select = SUN6I_GPADC_CTRL1_TP_ADC_SELECT,
84         .adc_chan_select = &sun6i_gpadc_chan_select,
85         .adc_chan_mask = SUN6I_GPADC_CTRL1_ADC_CHAN_MASK,
86 };
87
88 static const struct gpadc_data sun8i_a33_gpadc_data = {
89         .temp_offset = -1662,
90         .temp_scale = 162,
91         .tp_mode_en = SUN8I_GPADC_CTRL1_CHOP_TEMP_EN,
92 };
93
94 struct sun4i_gpadc_iio {
95         struct iio_dev                  *indio_dev;
96         struct completion               completion;
97         int                             temp_data;
98         u32                             adc_data;
99         struct regmap                   *regmap;
100         unsigned int                    fifo_data_irq;
101         atomic_t                        ignore_fifo_data_irq;
102         unsigned int                    temp_data_irq;
103         atomic_t                        ignore_temp_data_irq;
104         const struct gpadc_data         *data;
105         bool                            no_irq;
106         /* prevents concurrent reads of temperature and ADC */
107         struct mutex                    mutex;
108         struct thermal_zone_device      *tzd;
109         struct device                   *sensor_device;
110 };
111
112 #define SUN4I_GPADC_ADC_CHANNEL(_channel, _name) {              \
113         .type = IIO_VOLTAGE,                                    \
114         .indexed = 1,                                           \
115         .channel = _channel,                                    \
116         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),           \
117         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
118         .datasheet_name = _name,                                \
119 }
120
121 static struct iio_map sun4i_gpadc_hwmon_maps[] = {
122         {
123                 .adc_channel_label = "temp_adc",
124                 .consumer_dev_name = "iio_hwmon.0",
125         },
126         { /* sentinel */ },
127 };
128
129 static const struct iio_chan_spec sun4i_gpadc_channels[] = {
130         SUN4I_GPADC_ADC_CHANNEL(0, "adc_chan0"),
131         SUN4I_GPADC_ADC_CHANNEL(1, "adc_chan1"),
132         SUN4I_GPADC_ADC_CHANNEL(2, "adc_chan2"),
133         SUN4I_GPADC_ADC_CHANNEL(3, "adc_chan3"),
134         {
135                 .type = IIO_TEMP,
136                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
137                                       BIT(IIO_CHAN_INFO_SCALE) |
138                                       BIT(IIO_CHAN_INFO_OFFSET),
139                 .datasheet_name = "temp_adc",
140         },
141 };
142
143 static const struct iio_chan_spec sun4i_gpadc_channels_no_temp[] = {
144         SUN4I_GPADC_ADC_CHANNEL(0, "adc_chan0"),
145         SUN4I_GPADC_ADC_CHANNEL(1, "adc_chan1"),
146         SUN4I_GPADC_ADC_CHANNEL(2, "adc_chan2"),
147         SUN4I_GPADC_ADC_CHANNEL(3, "adc_chan3"),
148 };
149
150 static const struct iio_chan_spec sun8i_a33_gpadc_channels[] = {
151         {
152                 .type = IIO_TEMP,
153                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
154                                       BIT(IIO_CHAN_INFO_SCALE) |
155                                       BIT(IIO_CHAN_INFO_OFFSET),
156                 .datasheet_name = "temp_adc",
157         },
158 };
159
160 static const struct regmap_config sun4i_gpadc_regmap_config = {
161         .reg_bits = 32,
162         .val_bits = 32,
163         .reg_stride = 4,
164         .fast_io = true,
165 };
166
167 static int sun4i_prepare_for_irq(struct iio_dev *indio_dev, int channel,
168                                  unsigned int irq)
169 {
170         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
171         int ret;
172         u32 reg;
173
174         pm_runtime_get_sync(indio_dev->dev.parent);
175
176         reinit_completion(&info->completion);
177
178         ret = regmap_write(info->regmap, SUN4I_GPADC_INT_FIFOC,
179                            SUN4I_GPADC_INT_FIFOC_TP_FIFO_TRIG_LEVEL(1) |
180                            SUN4I_GPADC_INT_FIFOC_TP_FIFO_FLUSH);
181         if (ret)
182                 return ret;
183
184         ret = regmap_read(info->regmap, SUN4I_GPADC_CTRL1, &reg);
185         if (ret)
186                 return ret;
187
188         if (irq == info->fifo_data_irq) {
189                 ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1,
190                                    info->data->tp_mode_en |
191                                    info->data->tp_adc_select |
192                                    info->data->adc_chan_select(channel));
193                 /*
194                  * When the IP changes channel, it needs a bit of time to get
195                  * correct values.
196                  */
197                 if ((reg & info->data->adc_chan_mask) !=
198                          info->data->adc_chan_select(channel))
199                         mdelay(10);
200
201         } else {
202                 /*
203                  * The temperature sensor returns valid data only when the ADC
204                  * operates in touchscreen mode.
205                  */
206                 ret = regmap_write(info->regmap, SUN4I_GPADC_CTRL1,
207                                    info->data->tp_mode_en);
208         }
209
210         if (ret)
211                 return ret;
212
213         /*
214          * When the IP changes mode between ADC or touchscreen, it
215          * needs a bit of time to get correct values.
216          */
217         if ((reg & info->data->tp_adc_select) != info->data->tp_adc_select)
218                 mdelay(100);
219
220         return 0;
221 }
222
223 static int sun4i_gpadc_read(struct iio_dev *indio_dev, int channel, int *val,
224                             unsigned int irq)
225 {
226         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
227         int ret;
228
229         mutex_lock(&info->mutex);
230
231         ret = sun4i_prepare_for_irq(indio_dev, channel, irq);
232         if (ret)
233                 goto err;
234
235         enable_irq(irq);
236
237         /*
238          * The temperature sensor throws an interruption periodically (currently
239          * set at periods of ~0.6s in sun4i_gpadc_runtime_resume). A 1s delay
240          * makes sure an interruption occurs in normal conditions. If it doesn't
241          * occur, then there is a timeout.
242          */
243         if (!wait_for_completion_timeout(&info->completion,
244                                          msecs_to_jiffies(1000))) {
245                 ret = -ETIMEDOUT;
246                 goto err;
247         }
248
249         if (irq == info->fifo_data_irq)
250                 *val = info->adc_data;
251         else
252                 *val = info->temp_data;
253
254         ret = 0;
255         pm_runtime_mark_last_busy(indio_dev->dev.parent);
256
257 err:
258         pm_runtime_put_autosuspend(indio_dev->dev.parent);
259         disable_irq(irq);
260         mutex_unlock(&info->mutex);
261
262         return ret;
263 }
264
265 static int sun4i_gpadc_adc_read(struct iio_dev *indio_dev, int channel,
266                                 int *val)
267 {
268         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
269
270         return sun4i_gpadc_read(indio_dev, channel, val, info->fifo_data_irq);
271 }
272
273 static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val)
274 {
275         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
276
277         if (info->no_irq) {
278                 pm_runtime_get_sync(indio_dev->dev.parent);
279
280                 regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, val);
281
282                 pm_runtime_mark_last_busy(indio_dev->dev.parent);
283                 pm_runtime_put_autosuspend(indio_dev->dev.parent);
284
285                 return 0;
286         }
287
288         return sun4i_gpadc_read(indio_dev, 0, val, info->temp_data_irq);
289 }
290
291 static int sun4i_gpadc_temp_offset(struct iio_dev *indio_dev, int *val)
292 {
293         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
294
295         *val = info->data->temp_offset;
296
297         return 0;
298 }
299
300 static int sun4i_gpadc_temp_scale(struct iio_dev *indio_dev, int *val)
301 {
302         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
303
304         *val = info->data->temp_scale;
305
306         return 0;
307 }
308
309 static int sun4i_gpadc_read_raw(struct iio_dev *indio_dev,
310                                 struct iio_chan_spec const *chan, int *val,
311                                 int *val2, long mask)
312 {
313         int ret;
314
315         switch (mask) {
316         case IIO_CHAN_INFO_OFFSET:
317                 ret = sun4i_gpadc_temp_offset(indio_dev, val);
318                 if (ret)
319                         return ret;
320
321                 return IIO_VAL_INT;
322         case IIO_CHAN_INFO_RAW:
323                 if (chan->type == IIO_VOLTAGE)
324                         ret = sun4i_gpadc_adc_read(indio_dev, chan->channel,
325                                                    val);
326                 else
327                         ret = sun4i_gpadc_temp_read(indio_dev, val);
328
329                 if (ret)
330                         return ret;
331
332                 return IIO_VAL_INT;
333         case IIO_CHAN_INFO_SCALE:
334                 if (chan->type == IIO_VOLTAGE) {
335                         /* 3000mV / 4096 * raw */
336                         *val = 0;
337                         *val2 = 732421875;
338                         return IIO_VAL_INT_PLUS_NANO;
339                 }
340
341                 ret = sun4i_gpadc_temp_scale(indio_dev, val);
342                 if (ret)
343                         return ret;
344
345                 return IIO_VAL_INT;
346         default:
347                 return -EINVAL;
348         }
349
350         return -EINVAL;
351 }
352
353 static const struct iio_info sun4i_gpadc_iio_info = {
354         .read_raw = sun4i_gpadc_read_raw,
355 };
356
357 static irqreturn_t sun4i_gpadc_temp_data_irq_handler(int irq, void *dev_id)
358 {
359         struct sun4i_gpadc_iio *info = dev_id;
360
361         if (atomic_read(&info->ignore_temp_data_irq))
362                 goto out;
363
364         if (!regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, &info->temp_data))
365                 complete(&info->completion);
366
367 out:
368         return IRQ_HANDLED;
369 }
370
371 static irqreturn_t sun4i_gpadc_fifo_data_irq_handler(int irq, void *dev_id)
372 {
373         struct sun4i_gpadc_iio *info = dev_id;
374
375         if (atomic_read(&info->ignore_fifo_data_irq))
376                 goto out;
377
378         if (!regmap_read(info->regmap, SUN4I_GPADC_DATA, &info->adc_data))
379                 complete(&info->completion);
380
381 out:
382         return IRQ_HANDLED;
383 }
384
385 static int sun4i_gpadc_runtime_suspend(struct device *dev)
386 {
387         struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
388
389         /* Disable the ADC on IP */
390         regmap_write(info->regmap, SUN4I_GPADC_CTRL1, 0);
391         /* Disable temperature sensor on IP */
392         regmap_write(info->regmap, SUN4I_GPADC_TPR, 0);
393
394         return 0;
395 }
396
397 static int sun4i_gpadc_runtime_resume(struct device *dev)
398 {
399         struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
400
401         /* clkin = 6MHz */
402         regmap_write(info->regmap, SUN4I_GPADC_CTRL0,
403                      SUN4I_GPADC_CTRL0_ADC_CLK_DIVIDER(2) |
404                      SUN4I_GPADC_CTRL0_FS_DIV(7) |
405                      SUN4I_GPADC_CTRL0_T_ACQ(63));
406         regmap_write(info->regmap, SUN4I_GPADC_CTRL1, info->data->tp_mode_en);
407         regmap_write(info->regmap, SUN4I_GPADC_CTRL3,
408                      SUN4I_GPADC_CTRL3_FILTER_EN |
409                      SUN4I_GPADC_CTRL3_FILTER_TYPE(1));
410         /* period = SUN4I_GPADC_TPR_TEMP_PERIOD * 256 * 16 / clkin; ~0.6s */
411         regmap_write(info->regmap, SUN4I_GPADC_TPR,
412                      SUN4I_GPADC_TPR_TEMP_ENABLE |
413                      SUN4I_GPADC_TPR_TEMP_PERIOD(800));
414
415         return 0;
416 }
417
418 static int sun4i_gpadc_get_temp(void *data, int *temp)
419 {
420         struct sun4i_gpadc_iio *info = data;
421         int val, scale, offset;
422
423         if (sun4i_gpadc_temp_read(info->indio_dev, &val))
424                 return -ETIMEDOUT;
425
426         sun4i_gpadc_temp_scale(info->indio_dev, &scale);
427         sun4i_gpadc_temp_offset(info->indio_dev, &offset);
428
429         *temp = (val + offset) * scale;
430
431         return 0;
432 }
433
434 static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
435         .get_temp = &sun4i_gpadc_get_temp,
436 };
437
438 static const struct dev_pm_ops sun4i_gpadc_pm_ops = {
439         .runtime_suspend = &sun4i_gpadc_runtime_suspend,
440         .runtime_resume = &sun4i_gpadc_runtime_resume,
441 };
442
443 static int sun4i_irq_init(struct platform_device *pdev, const char *name,
444                           irq_handler_t handler, const char *devname,
445                           unsigned int *irq, atomic_t *atomic)
446 {
447         int ret;
448         struct sun4i_gpadc_dev *mfd_dev = dev_get_drvdata(pdev->dev.parent);
449         struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(&pdev->dev));
450
451         /*
452          * Once the interrupt is activated, the IP continuously performs
453          * conversions thus throws interrupts. The interrupt is activated right
454          * after being requested but we want to control when these interrupts
455          * occur thus we disable it right after being requested. However, an
456          * interrupt might occur between these two instructions and we have to
457          * make sure that does not happen, by using atomic flags. We set the
458          * flag before requesting the interrupt and unset it right after
459          * disabling the interrupt. When an interrupt occurs between these two
460          * instructions, reading the atomic flag will tell us to ignore the
461          * interrupt.
462          */
463         atomic_set(atomic, 1);
464
465         ret = platform_get_irq_byname(pdev, name);
466         if (ret < 0) {
467                 dev_err(&pdev->dev, "no %s interrupt registered\n", name);
468                 return ret;
469         }
470
471         ret = regmap_irq_get_virq(mfd_dev->regmap_irqc, ret);
472         if (ret < 0) {
473                 dev_err(&pdev->dev, "failed to get virq for irq %s\n", name);
474                 return ret;
475         }
476
477         *irq = ret;
478         ret = devm_request_any_context_irq(&pdev->dev, *irq, handler, 0,
479                                            devname, info);
480         if (ret < 0) {
481                 dev_err(&pdev->dev, "could not request %s interrupt: %d\n",
482                         name, ret);
483                 return ret;
484         }
485
486         disable_irq(*irq);
487         atomic_set(atomic, 0);
488
489         return 0;
490 }
491
492 static const struct of_device_id sun4i_gpadc_of_id[] = {
493         {
494                 .compatible = "allwinner,sun8i-a33-ths",
495                 .data = &sun8i_a33_gpadc_data,
496         },
497         { /* sentinel */ }
498 };
499
500 static int sun4i_gpadc_probe_dt(struct platform_device *pdev,
501                                 struct iio_dev *indio_dev)
502 {
503         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
504         struct resource *mem;
505         void __iomem *base;
506         int ret;
507
508         info->data = of_device_get_match_data(&pdev->dev);
509         if (!info->data)
510                 return -ENODEV;
511
512         info->no_irq = true;
513         indio_dev->num_channels = ARRAY_SIZE(sun8i_a33_gpadc_channels);
514         indio_dev->channels = sun8i_a33_gpadc_channels;
515
516         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
517         base = devm_ioremap_resource(&pdev->dev, mem);
518         if (IS_ERR(base))
519                 return PTR_ERR(base);
520
521         info->regmap = devm_regmap_init_mmio(&pdev->dev, base,
522                                              &sun4i_gpadc_regmap_config);
523         if (IS_ERR(info->regmap)) {
524                 ret = PTR_ERR(info->regmap);
525                 dev_err(&pdev->dev, "failed to init regmap: %d\n", ret);
526                 return ret;
527         }
528
529         if (IS_ENABLED(CONFIG_THERMAL_OF))
530                 info->sensor_device = &pdev->dev;
531
532         return 0;
533 }
534
535 static int sun4i_gpadc_probe_mfd(struct platform_device *pdev,
536                                  struct iio_dev *indio_dev)
537 {
538         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
539         struct sun4i_gpadc_dev *sun4i_gpadc_dev =
540                 dev_get_drvdata(pdev->dev.parent);
541         int ret;
542
543         info->no_irq = false;
544         info->regmap = sun4i_gpadc_dev->regmap;
545
546         indio_dev->num_channels = ARRAY_SIZE(sun4i_gpadc_channels);
547         indio_dev->channels = sun4i_gpadc_channels;
548
549         info->data = (struct gpadc_data *)platform_get_device_id(pdev)->driver_data;
550
551         /*
552          * Since the controller needs to be in touchscreen mode for its thermal
553          * sensor to operate properly, and that switching between the two modes
554          * needs a delay, always registering in the thermal framework will
555          * significantly slow down the conversion rate of the ADCs.
556          *
557          * Therefore, instead of depending on THERMAL_OF in Kconfig, we only
558          * register the sensor if that option is enabled, eventually leaving
559          * that choice to the user.
560          */
561
562         if (IS_ENABLED(CONFIG_THERMAL_OF)) {
563                 /*
564                  * This driver is a child of an MFD which has a node in the DT
565                  * but not its children, because of DT backward compatibility
566                  * for A10, A13 and A31 SoCs. Therefore, the resulting devices
567                  * of this driver do not have an of_node variable.
568                  * However, its parent (the MFD driver) has an of_node variable
569                  * and since devm_thermal_zone_of_sensor_register uses its first
570                  * argument to match the phandle defined in the node of the
571                  * thermal driver with the of_node of the device passed as first
572                  * argument and the third argument to call ops from
573                  * thermal_zone_of_device_ops, the solution is to use the parent
574                  * device as first argument to match the phandle with its
575                  * of_node, and the device from this driver as third argument to
576                  * return the temperature.
577                  */
578                 info->sensor_device = pdev->dev.parent;
579         } else {
580                 indio_dev->num_channels =
581                         ARRAY_SIZE(sun4i_gpadc_channels_no_temp);
582                 indio_dev->channels = sun4i_gpadc_channels_no_temp;
583         }
584
585         if (IS_ENABLED(CONFIG_THERMAL_OF)) {
586                 ret = sun4i_irq_init(pdev, "TEMP_DATA_PENDING",
587                                      sun4i_gpadc_temp_data_irq_handler,
588                                      "temp_data", &info->temp_data_irq,
589                                      &info->ignore_temp_data_irq);
590                 if (ret < 0)
591                         return ret;
592         }
593
594         ret = sun4i_irq_init(pdev, "FIFO_DATA_PENDING",
595                              sun4i_gpadc_fifo_data_irq_handler, "fifo_data",
596                              &info->fifo_data_irq, &info->ignore_fifo_data_irq);
597         if (ret < 0)
598                 return ret;
599
600         if (IS_ENABLED(CONFIG_THERMAL_OF)) {
601                 ret = iio_map_array_register(indio_dev, sun4i_gpadc_hwmon_maps);
602                 if (ret < 0) {
603                         dev_err(&pdev->dev,
604                                 "failed to register iio map array\n");
605                         return ret;
606                 }
607         }
608
609         return 0;
610 }
611
612 static int sun4i_gpadc_probe(struct platform_device *pdev)
613 {
614         struct sun4i_gpadc_iio *info;
615         struct iio_dev *indio_dev;
616         int ret;
617
618         indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
619         if (!indio_dev)
620                 return -ENOMEM;
621
622         info = iio_priv(indio_dev);
623         platform_set_drvdata(pdev, indio_dev);
624
625         mutex_init(&info->mutex);
626         info->indio_dev = indio_dev;
627         init_completion(&info->completion);
628         indio_dev->name = dev_name(&pdev->dev);
629         indio_dev->dev.parent = &pdev->dev;
630         indio_dev->dev.of_node = pdev->dev.of_node;
631         indio_dev->info = &sun4i_gpadc_iio_info;
632         indio_dev->modes = INDIO_DIRECT_MODE;
633
634         if (pdev->dev.of_node)
635                 ret = sun4i_gpadc_probe_dt(pdev, indio_dev);
636         else
637                 ret = sun4i_gpadc_probe_mfd(pdev, indio_dev);
638
639         if (ret)
640                 return ret;
641
642         pm_runtime_set_autosuspend_delay(&pdev->dev,
643                                          SUN4I_GPADC_AUTOSUSPEND_DELAY);
644         pm_runtime_use_autosuspend(&pdev->dev);
645         pm_runtime_set_suspended(&pdev->dev);
646         pm_runtime_enable(&pdev->dev);
647
648         if (IS_ENABLED(CONFIG_THERMAL_OF)) {
649                 info->tzd = thermal_zone_of_sensor_register(info->sensor_device,
650                                                             0, info,
651                                                             &sun4i_ts_tz_ops);
652                 /*
653                  * Do not fail driver probing when failing to register in
654                  * thermal because no thermal DT node is found.
655                  */
656                 if (IS_ERR(info->tzd) && PTR_ERR(info->tzd) != -ENODEV) {
657                         dev_err(&pdev->dev,
658                                 "could not register thermal sensor: %ld\n",
659                                 PTR_ERR(info->tzd));
660                         return PTR_ERR(info->tzd);
661                 }
662         }
663
664         ret = devm_iio_device_register(&pdev->dev, indio_dev);
665         if (ret < 0) {
666                 dev_err(&pdev->dev, "could not register the device\n");
667                 goto err_map;
668         }
669
670         return 0;
671
672 err_map:
673         if (!info->no_irq && IS_ENABLED(CONFIG_THERMAL_OF))
674                 iio_map_array_unregister(indio_dev);
675
676         pm_runtime_put(&pdev->dev);
677         pm_runtime_disable(&pdev->dev);
678
679         return ret;
680 }
681
682 static int sun4i_gpadc_remove(struct platform_device *pdev)
683 {
684         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
685         struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
686
687         pm_runtime_put(&pdev->dev);
688         pm_runtime_disable(&pdev->dev);
689
690         if (!IS_ENABLED(CONFIG_THERMAL_OF))
691                 return 0;
692
693         thermal_zone_of_sensor_unregister(info->sensor_device, info->tzd);
694
695         if (!info->no_irq)
696                 iio_map_array_unregister(indio_dev);
697
698         return 0;
699 }
700
701 static const struct platform_device_id sun4i_gpadc_id[] = {
702         { "sun4i-a10-gpadc-iio", (kernel_ulong_t)&sun4i_gpadc_data },
703         { "sun5i-a13-gpadc-iio", (kernel_ulong_t)&sun5i_gpadc_data },
704         { "sun6i-a31-gpadc-iio", (kernel_ulong_t)&sun6i_gpadc_data },
705         { /* sentinel */ },
706 };
707 MODULE_DEVICE_TABLE(platform, sun4i_gpadc_id);
708
709 static struct platform_driver sun4i_gpadc_driver = {
710         .driver = {
711                 .name = "sun4i-gpadc-iio",
712                 .of_match_table = sun4i_gpadc_of_id,
713                 .pm = &sun4i_gpadc_pm_ops,
714         },
715         .id_table = sun4i_gpadc_id,
716         .probe = sun4i_gpadc_probe,
717         .remove = sun4i_gpadc_remove,
718 };
719 MODULE_DEVICE_TABLE(of, sun4i_gpadc_of_id);
720
721 module_platform_driver(sun4i_gpadc_driver);
722
723 MODULE_DESCRIPTION("ADC driver for sunxi platforms");
724 MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
725 MODULE_LICENSE("GPL v2");