1 // SPDX-License-Identifier: GPL-2.0+
3 * Renesas R-Car GyroADC driver
5 * Copyright 2016 Marek Vasut <marek.vasut@gmail.com>
8 #include <linux/module.h>
9 #include <linux/platform_device.h>
10 #include <linux/delay.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
14 #include <linux/clk.h>
16 #include <linux/of_irq.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/of_platform.h>
19 #include <linux/err.h>
20 #include <linux/pm_runtime.h>
22 #include <linux/iio/iio.h>
23 #include <linux/iio/sysfs.h>
24 #include <linux/iio/trigger.h>
26 #define DRIVER_NAME "rcar-gyroadc"
28 /* GyroADC registers. */
29 #define RCAR_GYROADC_MODE_SELECT 0x00
30 #define RCAR_GYROADC_MODE_SELECT_1_MB88101A 0x0
31 #define RCAR_GYROADC_MODE_SELECT_2_ADCS7476 0x1
32 #define RCAR_GYROADC_MODE_SELECT_3_MAX1162 0x3
34 #define RCAR_GYROADC_START_STOP 0x04
35 #define RCAR_GYROADC_START_STOP_START BIT(0)
37 #define RCAR_GYROADC_CLOCK_LENGTH 0x08
38 #define RCAR_GYROADC_1_25MS_LENGTH 0x0c
40 #define RCAR_GYROADC_REALTIME_DATA(ch) (0x10 + ((ch) * 4))
41 #define RCAR_GYROADC_100MS_ADDED_DATA(ch) (0x30 + ((ch) * 4))
42 #define RCAR_GYROADC_10MS_AVG_DATA(ch) (0x50 + ((ch) * 4))
44 #define RCAR_GYROADC_FIFO_STATUS 0x70
45 #define RCAR_GYROADC_FIFO_STATUS_EMPTY(ch) BIT(0 + (4 * (ch)))
46 #define RCAR_GYROADC_FIFO_STATUS_FULL(ch) BIT(1 + (4 * (ch)))
47 #define RCAR_GYROADC_FIFO_STATUS_ERROR(ch) BIT(2 + (4 * (ch)))
49 #define RCAR_GYROADC_INTR 0x74
50 #define RCAR_GYROADC_INTR_INT BIT(0)
52 #define RCAR_GYROADC_INTENR 0x78
53 #define RCAR_GYROADC_INTENR_INTEN BIT(0)
55 #define RCAR_GYROADC_SAMPLE_RATE 800 /* Hz */
57 #define RCAR_GYROADC_RUNTIME_PM_DELAY_MS 2000
59 enum rcar_gyroadc_model {
60 RCAR_GYROADC_MODEL_DEFAULT,
61 RCAR_GYROADC_MODEL_R8A7792,
68 struct regulator *vref[8];
69 unsigned int num_channels;
70 enum rcar_gyroadc_model model;
72 unsigned int sample_width;
75 static void rcar_gyroadc_hw_init(struct rcar_gyroadc *priv)
77 const unsigned long clk_mhz = clk_get_rate(priv->clk) / 1000000;
78 const unsigned long clk_mul =
79 (priv->mode == RCAR_GYROADC_MODE_SELECT_1_MB88101A) ? 10 : 5;
80 unsigned long clk_len = clk_mhz * clk_mul;
83 * According to the R-Car Gen2 datasheet Rev. 1.01, Sept 08 2014,
84 * page 77-7, clock length must be even number. If it's odd number,
90 /* Stop the GyroADC. */
91 writel(0, priv->regs + RCAR_GYROADC_START_STOP);
93 /* Disable IRQ on V2H. */
94 if (priv->model == RCAR_GYROADC_MODEL_R8A7792)
95 writel(0, priv->regs + RCAR_GYROADC_INTENR);
97 /* Set mode and timing. */
98 writel(priv->mode, priv->regs + RCAR_GYROADC_MODE_SELECT);
99 writel(clk_len, priv->regs + RCAR_GYROADC_CLOCK_LENGTH);
100 writel(clk_mhz * 1250, priv->regs + RCAR_GYROADC_1_25MS_LENGTH);
103 static void rcar_gyroadc_hw_start(struct rcar_gyroadc *priv)
105 /* Start sampling. */
106 writel(RCAR_GYROADC_START_STOP_START,
107 priv->regs + RCAR_GYROADC_START_STOP);
110 * Wait for the first conversion to complete. This is longer than
111 * the 1.25 mS in the datasheet because 1.25 mS is not enough for
112 * the hardware to deliver the first sample and the hardware does
113 * then return zeroes instead of valid data.
118 static void rcar_gyroadc_hw_stop(struct rcar_gyroadc *priv)
120 /* Stop the GyroADC. */
121 writel(0, priv->regs + RCAR_GYROADC_START_STOP);
124 #define RCAR_GYROADC_CHAN(_idx) { \
125 .type = IIO_VOLTAGE, \
128 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
129 BIT(IIO_CHAN_INFO_SCALE), \
130 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
133 static const struct iio_chan_spec rcar_gyroadc_iio_channels_1[] = {
134 RCAR_GYROADC_CHAN(0),
135 RCAR_GYROADC_CHAN(1),
136 RCAR_GYROADC_CHAN(2),
137 RCAR_GYROADC_CHAN(3),
140 static const struct iio_chan_spec rcar_gyroadc_iio_channels_2[] = {
141 RCAR_GYROADC_CHAN(0),
142 RCAR_GYROADC_CHAN(1),
143 RCAR_GYROADC_CHAN(2),
144 RCAR_GYROADC_CHAN(3),
145 RCAR_GYROADC_CHAN(4),
146 RCAR_GYROADC_CHAN(5),
147 RCAR_GYROADC_CHAN(6),
148 RCAR_GYROADC_CHAN(7),
151 static const struct iio_chan_spec rcar_gyroadc_iio_channels_3[] = {
152 RCAR_GYROADC_CHAN(0),
153 RCAR_GYROADC_CHAN(1),
154 RCAR_GYROADC_CHAN(2),
155 RCAR_GYROADC_CHAN(3),
156 RCAR_GYROADC_CHAN(4),
157 RCAR_GYROADC_CHAN(5),
158 RCAR_GYROADC_CHAN(6),
159 RCAR_GYROADC_CHAN(7),
162 static int rcar_gyroadc_set_power(struct rcar_gyroadc *priv, bool on)
164 struct device *dev = priv->dev;
167 return pm_runtime_resume_and_get(dev);
169 pm_runtime_mark_last_busy(dev);
170 return pm_runtime_put_autosuspend(dev);
174 static int rcar_gyroadc_read_raw(struct iio_dev *indio_dev,
175 struct iio_chan_spec const *chan,
176 int *val, int *val2, long mask)
178 struct rcar_gyroadc *priv = iio_priv(indio_dev);
179 struct regulator *consumer;
180 unsigned int datareg = RCAR_GYROADC_REALTIME_DATA(chan->channel);
185 * MB88101 is special in that it has only single regulator for
188 if (priv->mode == RCAR_GYROADC_MODE_SELECT_1_MB88101A)
189 consumer = priv->vref[0];
191 consumer = priv->vref[chan->channel];
194 case IIO_CHAN_INFO_RAW:
195 if (chan->type != IIO_VOLTAGE)
198 /* Channel not connected. */
202 ret = iio_device_claim_direct_mode(indio_dev);
206 ret = rcar_gyroadc_set_power(priv, true);
208 iio_device_release_direct_mode(indio_dev);
212 *val = readl(priv->regs + datareg);
213 *val &= BIT(priv->sample_width) - 1;
215 ret = rcar_gyroadc_set_power(priv, false);
216 iio_device_release_direct_mode(indio_dev);
221 case IIO_CHAN_INFO_SCALE:
222 /* Channel not connected. */
226 vref = regulator_get_voltage(consumer);
228 *val2 = 1 << priv->sample_width;
230 return IIO_VAL_FRACTIONAL;
231 case IIO_CHAN_INFO_SAMP_FREQ:
232 *val = RCAR_GYROADC_SAMPLE_RATE;
240 static int rcar_gyroadc_reg_access(struct iio_dev *indio_dev,
241 unsigned int reg, unsigned int writeval,
242 unsigned int *readval)
244 struct rcar_gyroadc *priv = iio_priv(indio_dev);
245 unsigned int maxreg = RCAR_GYROADC_FIFO_STATUS;
253 /* Handle the V2H case with extra interrupt block. */
254 if (priv->model == RCAR_GYROADC_MODEL_R8A7792)
255 maxreg = RCAR_GYROADC_INTENR;
260 *readval = readl(priv->regs + reg);
265 static const struct iio_info rcar_gyroadc_iio_info = {
266 .read_raw = rcar_gyroadc_read_raw,
267 .debugfs_reg_access = rcar_gyroadc_reg_access,
270 static const struct of_device_id rcar_gyroadc_match[] = {
272 /* R-Car compatible GyroADC */
273 .compatible = "renesas,rcar-gyroadc",
274 .data = (void *)RCAR_GYROADC_MODEL_DEFAULT,
276 /* R-Car V2H specialty with interrupt registers. */
277 .compatible = "renesas,r8a7792-gyroadc",
278 .data = (void *)RCAR_GYROADC_MODEL_R8A7792,
284 MODULE_DEVICE_TABLE(of, rcar_gyroadc_match);
286 static const struct of_device_id rcar_gyroadc_child_match[] = {
289 .compatible = "fujitsu,mb88101a",
290 .data = (void *)RCAR_GYROADC_MODE_SELECT_1_MB88101A,
294 .compatible = "ti,adcs7476",
295 .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
297 .compatible = "ti,adc121",
298 .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
300 .compatible = "adi,ad7476",
301 .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
305 .compatible = "maxim,max1162",
306 .data = (void *)RCAR_GYROADC_MODE_SELECT_3_MAX1162,
308 .compatible = "maxim,max11100",
309 .data = (void *)RCAR_GYROADC_MODE_SELECT_3_MAX1162,
314 static int rcar_gyroadc_parse_subdevs(struct iio_dev *indio_dev)
316 const struct of_device_id *of_id;
317 const struct iio_chan_spec *channels;
318 struct rcar_gyroadc *priv = iio_priv(indio_dev);
319 struct device *dev = priv->dev;
320 struct device_node *np = dev->of_node;
321 struct device_node *child;
322 struct regulator *vref;
324 unsigned int adcmode = -1, childmode;
325 unsigned int sample_width;
326 unsigned int num_channels;
329 for_each_child_of_node(np, child) {
330 of_id = of_match_node(rcar_gyroadc_child_match, child);
332 dev_err(dev, "Ignoring unsupported ADC \"%pOFn\".",
337 childmode = (uintptr_t)of_id->data;
339 case RCAR_GYROADC_MODE_SELECT_1_MB88101A:
341 channels = rcar_gyroadc_iio_channels_1;
342 num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_1);
344 case RCAR_GYROADC_MODE_SELECT_2_ADCS7476:
346 channels = rcar_gyroadc_iio_channels_2;
347 num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_2);
349 case RCAR_GYROADC_MODE_SELECT_3_MAX1162:
351 channels = rcar_gyroadc_iio_channels_3;
352 num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_3);
359 * MB88101 is special in that it's only a single chip taking
360 * up all the CHS lines. Thus, the DT binding is also special
361 * and has no reg property. If we run into such ADC, handle
364 if (childmode == RCAR_GYROADC_MODE_SELECT_1_MB88101A) {
367 ret = of_property_read_u32(child, "reg", ®);
370 "Failed to get child reg property of ADC \"%pOFn\".\n",
372 goto err_of_node_put;
375 /* Channel number is too high. */
376 if (reg >= num_channels) {
378 "Only %i channels supported with %pOFn, but reg = <%i>.\n",
379 num_channels, child, reg);
384 /* Child node selected different mode than the rest. */
385 if (!first && (adcmode != childmode)) {
387 "Channel %i uses different ADC mode than the rest.\n",
392 /* Channel is valid, grab the regulator. */
393 dev->of_node = child;
394 vref = devm_regulator_get(dev, "vref");
397 dev_dbg(dev, "Channel %i 'vref' supply not connected.\n",
400 goto err_of_node_put;
403 priv->vref[reg] = vref;
408 /* First child node which passed sanity tests. */
412 priv->num_channels = num_channels;
413 priv->mode = childmode;
414 priv->sample_width = sample_width;
416 indio_dev->channels = channels;
417 indio_dev->num_channels = num_channels;
420 * MB88101 is special and we only have one such device
421 * attached to the GyroADC at a time, so if we found it,
422 * we can stop parsing here.
424 if (childmode == RCAR_GYROADC_MODE_SELECT_1_MB88101A) {
431 dev_err(dev, "No valid ADC channels found, aborting.\n");
444 static void rcar_gyroadc_deinit_supplies(struct iio_dev *indio_dev)
446 struct rcar_gyroadc *priv = iio_priv(indio_dev);
449 for (i = 0; i < priv->num_channels; i++) {
453 regulator_disable(priv->vref[i]);
457 static int rcar_gyroadc_init_supplies(struct iio_dev *indio_dev)
459 struct rcar_gyroadc *priv = iio_priv(indio_dev);
460 struct device *dev = priv->dev;
464 for (i = 0; i < priv->num_channels; i++) {
468 ret = regulator_enable(priv->vref[i]);
470 dev_err(dev, "Failed to enable regulator %i (ret=%i)\n",
479 rcar_gyroadc_deinit_supplies(indio_dev);
483 static int rcar_gyroadc_probe(struct platform_device *pdev)
485 struct device *dev = &pdev->dev;
486 struct rcar_gyroadc *priv;
487 struct iio_dev *indio_dev;
490 indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
494 priv = iio_priv(indio_dev);
497 priv->regs = devm_platform_ioremap_resource(pdev, 0);
498 if (IS_ERR(priv->regs))
499 return PTR_ERR(priv->regs);
501 priv->clk = devm_clk_get(dev, "fck");
502 if (IS_ERR(priv->clk))
503 return dev_err_probe(dev, PTR_ERR(priv->clk),
504 "Failed to get IF clock\n");
506 ret = rcar_gyroadc_parse_subdevs(indio_dev);
510 ret = rcar_gyroadc_init_supplies(indio_dev);
514 priv->model = (enum rcar_gyroadc_model)
515 of_device_get_match_data(&pdev->dev);
517 platform_set_drvdata(pdev, indio_dev);
519 indio_dev->name = DRIVER_NAME;
520 indio_dev->info = &rcar_gyroadc_iio_info;
521 indio_dev->modes = INDIO_DIRECT_MODE;
523 ret = clk_prepare_enable(priv->clk);
525 dev_err(dev, "Could not prepare or enable the IF clock.\n");
526 goto err_clk_if_enable;
529 pm_runtime_set_autosuspend_delay(dev, RCAR_GYROADC_RUNTIME_PM_DELAY_MS);
530 pm_runtime_use_autosuspend(dev);
531 pm_runtime_enable(dev);
533 ret = pm_runtime_resume_and_get(dev);
537 rcar_gyroadc_hw_init(priv);
538 rcar_gyroadc_hw_start(priv);
540 ret = iio_device_register(indio_dev);
542 dev_err(dev, "Couldn't register IIO device.\n");
543 goto err_iio_device_register;
546 pm_runtime_put_sync(dev);
550 err_iio_device_register:
551 rcar_gyroadc_hw_stop(priv);
552 pm_runtime_put_sync(dev);
554 pm_runtime_disable(dev);
555 pm_runtime_set_suspended(dev);
556 clk_disable_unprepare(priv->clk);
558 rcar_gyroadc_deinit_supplies(indio_dev);
563 static int rcar_gyroadc_remove(struct platform_device *pdev)
565 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
566 struct rcar_gyroadc *priv = iio_priv(indio_dev);
567 struct device *dev = priv->dev;
569 iio_device_unregister(indio_dev);
570 pm_runtime_get_sync(dev);
571 rcar_gyroadc_hw_stop(priv);
572 pm_runtime_put_sync(dev);
573 pm_runtime_disable(dev);
574 pm_runtime_set_suspended(dev);
575 clk_disable_unprepare(priv->clk);
576 rcar_gyroadc_deinit_supplies(indio_dev);
581 #if defined(CONFIG_PM)
582 static int rcar_gyroadc_suspend(struct device *dev)
584 struct iio_dev *indio_dev = dev_get_drvdata(dev);
585 struct rcar_gyroadc *priv = iio_priv(indio_dev);
587 rcar_gyroadc_hw_stop(priv);
592 static int rcar_gyroadc_resume(struct device *dev)
594 struct iio_dev *indio_dev = dev_get_drvdata(dev);
595 struct rcar_gyroadc *priv = iio_priv(indio_dev);
597 rcar_gyroadc_hw_start(priv);
603 static const struct dev_pm_ops rcar_gyroadc_pm_ops = {
604 SET_RUNTIME_PM_OPS(rcar_gyroadc_suspend, rcar_gyroadc_resume, NULL)
607 static struct platform_driver rcar_gyroadc_driver = {
608 .probe = rcar_gyroadc_probe,
609 .remove = rcar_gyroadc_remove,
612 .of_match_table = rcar_gyroadc_match,
613 .pm = &rcar_gyroadc_pm_ops,
617 module_platform_driver(rcar_gyroadc_driver);
619 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
620 MODULE_DESCRIPTION("Renesas R-Car GyroADC driver");
621 MODULE_LICENSE("GPL");