2 * Renesas R-Car GyroADC driver
4 * Copyright 2016 Marek Vasut <marek.vasut@gmail.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
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/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/delay.h>
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
23 #include <linux/clk.h>
25 #include <linux/of_irq.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/of_platform.h>
28 #include <linux/err.h>
29 #include <linux/pm_runtime.h>
31 #include <linux/iio/iio.h>
32 #include <linux/iio/sysfs.h>
33 #include <linux/iio/trigger.h>
35 #define DRIVER_NAME "rcar-gyroadc"
37 /* GyroADC registers. */
38 #define RCAR_GYROADC_MODE_SELECT 0x00
39 #define RCAR_GYROADC_MODE_SELECT_1_MB88101A 0x0
40 #define RCAR_GYROADC_MODE_SELECT_2_ADCS7476 0x1
41 #define RCAR_GYROADC_MODE_SELECT_3_MAX1162 0x3
43 #define RCAR_GYROADC_START_STOP 0x04
44 #define RCAR_GYROADC_START_STOP_START BIT(0)
46 #define RCAR_GYROADC_CLOCK_LENGTH 0x08
47 #define RCAR_GYROADC_1_25MS_LENGTH 0x0c
49 #define RCAR_GYROADC_REALTIME_DATA(ch) (0x10 + ((ch) * 4))
50 #define RCAR_GYROADC_100MS_ADDED_DATA(ch) (0x30 + ((ch) * 4))
51 #define RCAR_GYROADC_10MS_AVG_DATA(ch) (0x50 + ((ch) * 4))
53 #define RCAR_GYROADC_FIFO_STATUS 0x70
54 #define RCAR_GYROADC_FIFO_STATUS_EMPTY(ch) BIT(0 + (4 * (ch)))
55 #define RCAR_GYROADC_FIFO_STATUS_FULL(ch) BIT(1 + (4 * (ch)))
56 #define RCAR_GYROADC_FIFO_STATUS_ERROR(ch) BIT(2 + (4 * (ch)))
58 #define RCAR_GYROADC_INTR 0x74
59 #define RCAR_GYROADC_INTR_INT BIT(0)
61 #define RCAR_GYROADC_INTENR 0x78
62 #define RCAR_GYROADC_INTENR_INTEN BIT(0)
64 #define RCAR_GYROADC_SAMPLE_RATE 800 /* Hz */
66 #define RCAR_GYROADC_RUNTIME_PM_DELAY_MS 2000
68 enum rcar_gyroadc_model {
69 RCAR_GYROADC_MODEL_DEFAULT,
70 RCAR_GYROADC_MODEL_R8A7792,
77 struct regulator *vref[8];
78 unsigned int num_channels;
79 enum rcar_gyroadc_model model;
81 unsigned int sample_width;
84 static void rcar_gyroadc_hw_init(struct rcar_gyroadc *priv)
86 const unsigned long clk_mhz = clk_get_rate(priv->iclk) / 1000000;
87 const unsigned long clk_mul =
88 (priv->mode == RCAR_GYROADC_MODE_SELECT_1_MB88101A) ? 10 : 5;
89 unsigned long clk_len = clk_mhz * clk_mul;
92 * According to the R-Car Gen2 datasheet Rev. 1.01, Sept 08 2014,
93 * page 77-7, clock length must be even number. If it's odd number,
99 /* Stop the GyroADC. */
100 writel(0, priv->regs + RCAR_GYROADC_START_STOP);
102 /* Disable IRQ on V2H. */
103 if (priv->model == RCAR_GYROADC_MODEL_R8A7792)
104 writel(0, priv->regs + RCAR_GYROADC_INTENR);
106 /* Set mode and timing. */
107 writel(priv->mode, priv->regs + RCAR_GYROADC_MODE_SELECT);
108 writel(clk_len, priv->regs + RCAR_GYROADC_CLOCK_LENGTH);
109 writel(clk_mhz * 1250, priv->regs + RCAR_GYROADC_1_25MS_LENGTH);
112 static void rcar_gyroadc_hw_start(struct rcar_gyroadc *priv)
114 /* Start sampling. */
115 writel(RCAR_GYROADC_START_STOP_START,
116 priv->regs + RCAR_GYROADC_START_STOP);
119 * Wait for the first conversion to complete. This is longer than
120 * the 1.25 mS in the datasheet because 1.25 mS is not enough for
121 * the hardware to deliver the first sample and the hardware does
122 * then return zeroes instead of valid data.
127 static void rcar_gyroadc_hw_stop(struct rcar_gyroadc *priv)
129 /* Stop the GyroADC. */
130 writel(0, priv->regs + RCAR_GYROADC_START_STOP);
133 #define RCAR_GYROADC_CHAN(_idx) { \
134 .type = IIO_VOLTAGE, \
137 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
138 BIT(IIO_CHAN_INFO_SCALE), \
139 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
142 static const struct iio_chan_spec rcar_gyroadc_iio_channels_1[] = {
143 RCAR_GYROADC_CHAN(0),
144 RCAR_GYROADC_CHAN(1),
145 RCAR_GYROADC_CHAN(2),
146 RCAR_GYROADC_CHAN(3),
149 static const struct iio_chan_spec rcar_gyroadc_iio_channels_2[] = {
150 RCAR_GYROADC_CHAN(0),
151 RCAR_GYROADC_CHAN(1),
152 RCAR_GYROADC_CHAN(2),
153 RCAR_GYROADC_CHAN(3),
154 RCAR_GYROADC_CHAN(4),
155 RCAR_GYROADC_CHAN(5),
156 RCAR_GYROADC_CHAN(6),
157 RCAR_GYROADC_CHAN(7),
160 static const struct iio_chan_spec rcar_gyroadc_iio_channels_3[] = {
161 RCAR_GYROADC_CHAN(0),
162 RCAR_GYROADC_CHAN(1),
163 RCAR_GYROADC_CHAN(2),
164 RCAR_GYROADC_CHAN(3),
165 RCAR_GYROADC_CHAN(4),
166 RCAR_GYROADC_CHAN(5),
167 RCAR_GYROADC_CHAN(6),
168 RCAR_GYROADC_CHAN(7),
171 static int rcar_gyroadc_set_power(struct rcar_gyroadc *priv, bool on)
173 struct device *dev = priv->dev;
177 ret = pm_runtime_get_sync(dev);
179 pm_runtime_put_noidle(dev);
181 pm_runtime_mark_last_busy(dev);
182 ret = pm_runtime_put_autosuspend(dev);
188 static int rcar_gyroadc_read_raw(struct iio_dev *indio_dev,
189 struct iio_chan_spec const *chan,
190 int *val, int *val2, long mask)
192 struct rcar_gyroadc *priv = iio_priv(indio_dev);
193 struct regulator *consumer;
194 unsigned int datareg = RCAR_GYROADC_REALTIME_DATA(chan->channel);
199 * MB88101 is special in that it has only single regulator for
202 if (priv->mode == RCAR_GYROADC_MODE_SELECT_1_MB88101A)
203 consumer = priv->vref[0];
205 consumer = priv->vref[chan->channel];
208 case IIO_CHAN_INFO_RAW:
209 if (chan->type != IIO_VOLTAGE)
212 /* Channel not connected. */
216 ret = iio_device_claim_direct_mode(indio_dev);
220 ret = rcar_gyroadc_set_power(priv, true);
222 iio_device_release_direct_mode(indio_dev);
226 *val = readl(priv->regs + datareg);
227 *val &= BIT(priv->sample_width) - 1;
229 ret = rcar_gyroadc_set_power(priv, false);
230 iio_device_release_direct_mode(indio_dev);
235 case IIO_CHAN_INFO_SCALE:
236 /* Channel not connected. */
240 vref = regulator_get_voltage(consumer);
242 *val2 = 1 << priv->sample_width;
244 return IIO_VAL_FRACTIONAL;
245 case IIO_CHAN_INFO_SAMP_FREQ:
246 *val = RCAR_GYROADC_SAMPLE_RATE;
254 static int rcar_gyroadc_reg_access(struct iio_dev *indio_dev,
255 unsigned int reg, unsigned int writeval,
256 unsigned int *readval)
258 struct rcar_gyroadc *priv = iio_priv(indio_dev);
259 unsigned int maxreg = RCAR_GYROADC_FIFO_STATUS;
267 /* Handle the V2H case with extra interrupt block. */
268 if (priv->model == RCAR_GYROADC_MODEL_R8A7792)
269 maxreg = RCAR_GYROADC_INTENR;
274 *readval = readl(priv->regs + reg);
279 static const struct iio_info rcar_gyroadc_iio_info = {
280 .driver_module = THIS_MODULE,
281 .read_raw = rcar_gyroadc_read_raw,
282 .debugfs_reg_access = rcar_gyroadc_reg_access,
285 static const struct of_device_id rcar_gyroadc_match[] = {
287 /* R-Car compatible GyroADC */
288 .compatible = "renesas,rcar-gyroadc",
289 .data = (void *)RCAR_GYROADC_MODEL_DEFAULT,
291 /* R-Car V2H specialty with interrupt registers. */
292 .compatible = "renesas,r8a7792-gyroadc",
293 .data = (void *)RCAR_GYROADC_MODEL_R8A7792,
299 MODULE_DEVICE_TABLE(of, rcar_gyroadc_match);
301 static const struct of_device_id rcar_gyroadc_child_match[] = {
304 .compatible = "fujitsu,mb88101a",
305 .data = (void *)RCAR_GYROADC_MODE_SELECT_1_MB88101A,
309 .compatible = "ti,adcs7476",
310 .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
312 .compatible = "ti,adc121",
313 .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
315 .compatible = "adi,ad7476",
316 .data = (void *)RCAR_GYROADC_MODE_SELECT_2_ADCS7476,
320 .compatible = "maxim,max1162",
321 .data = (void *)RCAR_GYROADC_MODE_SELECT_3_MAX1162,
323 .compatible = "maxim,max11100",
324 .data = (void *)RCAR_GYROADC_MODE_SELECT_3_MAX1162,
329 static int rcar_gyroadc_parse_subdevs(struct iio_dev *indio_dev)
331 const struct of_device_id *of_id;
332 const struct iio_chan_spec *channels;
333 struct rcar_gyroadc *priv = iio_priv(indio_dev);
334 struct device *dev = priv->dev;
335 struct device_node *np = dev->of_node;
336 struct device_node *child;
337 struct regulator *vref;
339 unsigned int adcmode = -1, childmode;
340 unsigned int sample_width;
341 unsigned int num_channels;
344 for_each_child_of_node(np, child) {
345 of_id = of_match_node(rcar_gyroadc_child_match, child);
347 dev_err(dev, "Ignoring unsupported ADC \"%s\".",
352 childmode = (unsigned int)of_id->data;
354 case RCAR_GYROADC_MODE_SELECT_1_MB88101A:
356 channels = rcar_gyroadc_iio_channels_1;
357 num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_1);
359 case RCAR_GYROADC_MODE_SELECT_2_ADCS7476:
361 channels = rcar_gyroadc_iio_channels_2;
362 num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_2);
364 case RCAR_GYROADC_MODE_SELECT_3_MAX1162:
366 channels = rcar_gyroadc_iio_channels_3;
367 num_channels = ARRAY_SIZE(rcar_gyroadc_iio_channels_3);
374 * MB88101 is special in that it's only a single chip taking
375 * up all the CHS lines. Thus, the DT binding is also special
376 * and has no reg property. If we run into such ADC, handle
379 if (childmode == RCAR_GYROADC_MODE_SELECT_1_MB88101A) {
382 ret = of_property_read_u32(child, "reg", ®);
385 "Failed to get child reg property of ADC \"%s\".\n",
390 /* Channel number is too high. */
391 if (reg >= num_channels) {
393 "Only %i channels supported with %s, but reg = <%i>.\n",
394 num_channels, child->name, reg);
399 /* Child node selected different mode than the rest. */
400 if (!first && (adcmode != childmode)) {
402 "Channel %i uses different ADC mode than the rest.\n",
407 /* Channel is valid, grab the regulator. */
408 dev->of_node = child;
409 vref = devm_regulator_get(dev, "vref");
412 dev_dbg(dev, "Channel %i 'vref' supply not connected.\n",
414 return PTR_ERR(vref);
417 priv->vref[reg] = vref;
422 /* First child node which passed sanity tests. */
426 priv->num_channels = num_channels;
427 priv->mode = childmode;
428 priv->sample_width = sample_width;
430 indio_dev->channels = channels;
431 indio_dev->num_channels = num_channels;
434 * MB88101 is special and we only have one such device
435 * attached to the GyroADC at a time, so if we found it,
436 * we can stop parsing here.
438 if (childmode == RCAR_GYROADC_MODE_SELECT_1_MB88101A)
443 dev_err(dev, "No valid ADC channels found, aborting.\n");
450 static void rcar_gyroadc_deinit_supplies(struct iio_dev *indio_dev)
452 struct rcar_gyroadc *priv = iio_priv(indio_dev);
455 for (i = 0; i < priv->num_channels; i++) {
459 regulator_disable(priv->vref[i]);
463 static int rcar_gyroadc_init_supplies(struct iio_dev *indio_dev)
465 struct rcar_gyroadc *priv = iio_priv(indio_dev);
466 struct device *dev = priv->dev;
470 for (i = 0; i < priv->num_channels; i++) {
474 ret = regulator_enable(priv->vref[i]);
476 dev_err(dev, "Failed to enable regulator %i (ret=%i)\n",
485 rcar_gyroadc_deinit_supplies(indio_dev);
489 static int rcar_gyroadc_probe(struct platform_device *pdev)
491 const struct of_device_id *of_id =
492 of_match_device(rcar_gyroadc_match, &pdev->dev);
493 struct device *dev = &pdev->dev;
494 struct rcar_gyroadc *priv;
495 struct iio_dev *indio_dev;
496 struct resource *mem;
499 indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
501 dev_err(dev, "Failed to allocate IIO device.\n");
505 priv = iio_priv(indio_dev);
508 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
509 priv->regs = devm_ioremap_resource(dev, mem);
510 if (IS_ERR(priv->regs))
511 return PTR_ERR(priv->regs);
513 priv->iclk = devm_clk_get(dev, "if");
514 if (IS_ERR(priv->iclk)) {
515 ret = PTR_ERR(priv->iclk);
516 if (ret != -EPROBE_DEFER)
517 dev_err(dev, "Failed to get IF clock (ret=%i)\n", ret);
521 ret = rcar_gyroadc_parse_subdevs(indio_dev);
525 ret = rcar_gyroadc_init_supplies(indio_dev);
529 priv->model = (enum rcar_gyroadc_model)of_id->data;
531 platform_set_drvdata(pdev, indio_dev);
533 indio_dev->name = DRIVER_NAME;
534 indio_dev->dev.parent = dev;
535 indio_dev->dev.of_node = pdev->dev.of_node;
536 indio_dev->info = &rcar_gyroadc_iio_info;
537 indio_dev->modes = INDIO_DIRECT_MODE;
539 ret = clk_prepare_enable(priv->iclk);
541 dev_err(dev, "Could not prepare or enable the IF clock.\n");
542 goto err_clk_if_enable;
545 pm_runtime_set_autosuspend_delay(dev, RCAR_GYROADC_RUNTIME_PM_DELAY_MS);
546 pm_runtime_use_autosuspend(dev);
547 pm_runtime_enable(dev);
549 pm_runtime_get_sync(dev);
550 rcar_gyroadc_hw_init(priv);
551 rcar_gyroadc_hw_start(priv);
553 ret = iio_device_register(indio_dev);
555 dev_err(dev, "Couldn't register IIO device.\n");
556 goto err_iio_device_register;
559 pm_runtime_put_sync(dev);
563 err_iio_device_register:
564 rcar_gyroadc_hw_stop(priv);
565 pm_runtime_put_sync(dev);
566 pm_runtime_disable(dev);
567 pm_runtime_set_suspended(dev);
568 clk_disable_unprepare(priv->iclk);
570 rcar_gyroadc_deinit_supplies(indio_dev);
575 static int rcar_gyroadc_remove(struct platform_device *pdev)
577 struct iio_dev *indio_dev = platform_get_drvdata(pdev);
578 struct rcar_gyroadc *priv = iio_priv(indio_dev);
579 struct device *dev = priv->dev;
581 iio_device_unregister(indio_dev);
582 pm_runtime_get_sync(dev);
583 rcar_gyroadc_hw_stop(priv);
584 pm_runtime_put_sync(dev);
585 pm_runtime_disable(dev);
586 pm_runtime_set_suspended(dev);
587 clk_disable_unprepare(priv->iclk);
588 rcar_gyroadc_deinit_supplies(indio_dev);
593 #if defined(CONFIG_PM)
594 static int rcar_gyroadc_suspend(struct device *dev)
596 struct iio_dev *indio_dev = dev_get_drvdata(dev);
597 struct rcar_gyroadc *priv = iio_priv(indio_dev);
599 rcar_gyroadc_hw_stop(priv);
604 static int rcar_gyroadc_resume(struct device *dev)
606 struct iio_dev *indio_dev = dev_get_drvdata(dev);
607 struct rcar_gyroadc *priv = iio_priv(indio_dev);
609 rcar_gyroadc_hw_start(priv);
615 static const struct dev_pm_ops rcar_gyroadc_pm_ops = {
616 SET_RUNTIME_PM_OPS(rcar_gyroadc_suspend, rcar_gyroadc_resume, NULL)
619 static struct platform_driver rcar_gyroadc_driver = {
620 .probe = rcar_gyroadc_probe,
621 .remove = rcar_gyroadc_remove,
624 .of_match_table = rcar_gyroadc_match,
625 .pm = &rcar_gyroadc_pm_ops,
629 module_platform_driver(rcar_gyroadc_driver);
631 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
632 MODULE_DESCRIPTION("Renesas R-Car GyroADC driver");
633 MODULE_LICENSE("GPL");