Free Electrons

Embedded Linux Experts

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
/*
 * HWMON Driver for Dialog DA9052
 *
 * Copyright(c) 2012 Dialog Semiconductor Ltd.
 *
 * Author: David Dajun Chen <dchen@diasemi.com>
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 *
 */

#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/property.h>

#include <linux/mfd/da9052/da9052.h>
#include <linux/mfd/da9052/reg.h>
#include <linux/regulator/consumer.h>

struct da9052_hwmon {
	struct da9052		*da9052;
	struct mutex		hwmon_lock;
	bool			tsi_as_adc;
	int			tsiref_mv;
	struct regulator	*tsiref;
	struct completion	tsidone;
};

static const char * const input_names[] = {
	[DA9052_ADC_VDDOUT]	=	"VDDOUT",
	[DA9052_ADC_ICH]	=	"CHARGING CURRENT",
	[DA9052_ADC_TBAT]	=	"BATTERY TEMP",
	[DA9052_ADC_VBAT]	=	"BATTERY VOLTAGE",
	[DA9052_ADC_IN4]	=	"ADC IN4",
	[DA9052_ADC_IN5]	=	"ADC IN5",
	[DA9052_ADC_IN6]	=	"ADC IN6",
	[DA9052_ADC_TSI_XP]	=	"ADC TS X+",
	[DA9052_ADC_TSI_YP]	=	"ADC TS Y+",
	[DA9052_ADC_TSI_XN]	=	"ADC TS X-",
	[DA9052_ADC_TSI_YN]	=	"ADC TS Y-",
	[DA9052_ADC_TJUNC]	=	"BATTERY JUNCTION TEMP",
	[DA9052_ADC_VBBAT]	=	"BACK-UP BATTERY VOLTAGE",
};

/* Conversion function for VDDOUT and VBAT */
static inline int volt_reg_to_mv(int value)
{
	return DIV_ROUND_CLOSEST(value * 2000, 1023) + 2500;
}

/* Conversion function for ADC channels 4, 5 and 6 */
static inline int input_reg_to_mv(int value)
{
	return DIV_ROUND_CLOSEST(value * 2500, 1023);
}

/* Conversion function for VBBAT */
static inline int vbbat_reg_to_mv(int value)
{
	return DIV_ROUND_CLOSEST(value * 5000, 1023);
}

static inline int input_tsireg_to_mv(struct da9052_hwmon *hwmon, int value)
{
	return DIV_ROUND_CLOSEST(value * hwmon->tsiref_mv, 1023);
}

static inline int da9052_enable_vddout_channel(struct da9052 *da9052)
{
	return da9052_reg_update(da9052, DA9052_ADC_CONT_REG,
				 DA9052_ADCCONT_AUTOVDDEN,
				 DA9052_ADCCONT_AUTOVDDEN);
}

static inline int da9052_disable_vddout_channel(struct da9052 *da9052)
{
	return da9052_reg_update(da9052, DA9052_ADC_CONT_REG,
				 DA9052_ADCCONT_AUTOVDDEN, 0);
}

static ssize_t da9052_read_vddout(struct device *dev,
				  struct device_attribute *devattr, char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int ret, vdd;

	mutex_lock(&hwmon->hwmon_lock);

	ret = da9052_enable_vddout_channel(hwmon->da9052);
	if (ret < 0)
		goto hwmon_err;

	vdd = da9052_reg_read(hwmon->da9052, DA9052_VDD_RES_REG);
	if (vdd < 0) {
		ret = vdd;
		goto hwmon_err_release;
	}

	ret = da9052_disable_vddout_channel(hwmon->da9052);
	if (ret < 0)
		goto hwmon_err;

	mutex_unlock(&hwmon->hwmon_lock);
	return sprintf(buf, "%d\n", volt_reg_to_mv(vdd));

hwmon_err_release:
	da9052_disable_vddout_channel(hwmon->da9052);
hwmon_err:
	mutex_unlock(&hwmon->hwmon_lock);
	return ret;
}

static ssize_t da9052_read_ich(struct device *dev,
			       struct device_attribute *devattr, char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int ret;

	ret = da9052_reg_read(hwmon->da9052, DA9052_ICHG_AV_REG);
	if (ret < 0)
		return ret;

	/* Equivalent to 3.9mA/bit in register ICHG_AV */
	return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(ret * 39, 10));
}

static ssize_t da9052_read_tbat(struct device *dev,
				struct device_attribute *devattr, char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n", da9052_adc_read_temp(hwmon->da9052));
}

static ssize_t da9052_read_vbat(struct device *dev,
				struct device_attribute *devattr, char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int ret;

	ret = da9052_adc_manual_read(hwmon->da9052, DA9052_ADC_VBAT);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", volt_reg_to_mv(ret));
}

static ssize_t da9052_read_misc_channel(struct device *dev,
					struct device_attribute *devattr,
					char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int channel = to_sensor_dev_attr(devattr)->index;
	int ret;

	ret = da9052_adc_manual_read(hwmon->da9052, channel);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", input_reg_to_mv(ret));
}

static int da9052_request_tsi_read(struct da9052_hwmon *hwmon, int channel)
{
	u8 val = DA9052_TSICONTB_TSIMAN;

	switch (channel) {
	case DA9052_ADC_TSI_XP:
		val |= DA9052_TSICONTB_TSIMUX_XP;
		break;
	case DA9052_ADC_TSI_YP:
		val |= DA9052_TSICONTB_TSIMUX_YP;
		break;
	case DA9052_ADC_TSI_XN:
		val |= DA9052_TSICONTB_TSIMUX_XN;
		break;
	case DA9052_ADC_TSI_YN:
		val |= DA9052_TSICONTB_TSIMUX_YN;
		break;
	}

	return da9052_reg_write(hwmon->da9052, DA9052_TSI_CONT_B_REG, val);
}

static int da9052_get_tsi_result(struct da9052_hwmon *hwmon, int channel)
{
	u8 regs[3];
	int msb, lsb, err;

	/* block read to avoid separation of MSB and LSB */
	err = da9052_group_read(hwmon->da9052, DA9052_TSI_X_MSB_REG,
				ARRAY_SIZE(regs), regs);
	if (err)
		return err;

	switch (channel) {
	case DA9052_ADC_TSI_XP:
	case DA9052_ADC_TSI_XN:
		msb = regs[0] << DA9052_TSILSB_TSIXL_BITS;
		lsb = regs[2] & DA9052_TSILSB_TSIXL;
		lsb >>= DA9052_TSILSB_TSIXL_SHIFT;
		break;
	case DA9052_ADC_TSI_YP:
	case DA9052_ADC_TSI_YN:
		msb = regs[1] << DA9052_TSILSB_TSIYL_BITS;
		lsb = regs[2] & DA9052_TSILSB_TSIYL;
		lsb >>= DA9052_TSILSB_TSIYL_SHIFT;
		break;
	default:
		return -EINVAL;
	}

	return msb | lsb;
}


static ssize_t __da9052_read_tsi(struct device *dev, int channel)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int ret;

	reinit_completion(&hwmon->tsidone);

	ret = da9052_request_tsi_read(hwmon, channel);
	if (ret < 0)
		return ret;

	/* Wait for an conversion done interrupt */
	if (!wait_for_completion_timeout(&hwmon->tsidone,
					 msecs_to_jiffies(500)))
		return -ETIMEDOUT;

	return da9052_get_tsi_result(hwmon, channel);
}

static ssize_t da9052_read_tsi(struct device *dev,
			       struct device_attribute *devattr,
			       char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int channel = to_sensor_dev_attr(devattr)->index;
	int ret;

	mutex_lock(&hwmon->hwmon_lock);
	ret = __da9052_read_tsi(dev, channel);
	mutex_unlock(&hwmon->hwmon_lock);

	if (ret < 0)
		return ret;
	else
		return sprintf(buf, "%d\n", input_tsireg_to_mv(hwmon, ret));
}

static ssize_t da9052_read_tjunc(struct device *dev,
				 struct device_attribute *devattr, char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int tjunc;
	int toffset;

	tjunc = da9052_reg_read(hwmon->da9052, DA9052_TJUNC_RES_REG);
	if (tjunc < 0)
		return tjunc;

	toffset = da9052_reg_read(hwmon->da9052, DA9052_T_OFFSET_REG);
	if (toffset < 0)
		return toffset;

	/*
	 * Degrees celsius = 1.708 * (TJUNC_RES - T_OFFSET) - 108.8
	 * T_OFFSET is a trim value used to improve accuracy of the result
	 */
	return sprintf(buf, "%d\n", 1708 * (tjunc - toffset) - 108800);
}

static ssize_t da9052_read_vbbat(struct device *dev,
				 struct device_attribute *devattr, char *buf)
{
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	int ret;

	ret = da9052_adc_manual_read(hwmon->da9052, DA9052_ADC_VBBAT);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", vbbat_reg_to_mv(ret));
}

static ssize_t show_label(struct device *dev,
			  struct device_attribute *devattr, char *buf)
{
	return sprintf(buf, "%s\n",
		       input_names[to_sensor_dev_attr(devattr)->index]);
}

static umode_t da9052_channel_is_visible(struct kobject *kobj,
					 struct attribute *attr, int index)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
	struct device_attribute *dattr = container_of(attr,
				struct device_attribute, attr);
	struct sensor_device_attribute *sattr = to_sensor_dev_attr(dattr);

	if (!hwmon->tsi_as_adc) {
		switch (sattr->index) {
		case DA9052_ADC_TSI_XP:
		case DA9052_ADC_TSI_YP:
		case DA9052_ADC_TSI_XN:
		case DA9052_ADC_TSI_YN:
			return 0;
		}
	}

	return attr->mode;
}

static SENSOR_DEVICE_ATTR(in0_input, 0444, da9052_read_vddout, NULL,
			  DA9052_ADC_VDDOUT);
static SENSOR_DEVICE_ATTR(in0_label, 0444, show_label, NULL,
			  DA9052_ADC_VDDOUT);
static SENSOR_DEVICE_ATTR(in3_input, 0444, da9052_read_vbat, NULL,
			  DA9052_ADC_VBAT);
static SENSOR_DEVICE_ATTR(in3_label, 0444, show_label, NULL,
			  DA9052_ADC_VBAT);
static SENSOR_DEVICE_ATTR(in4_input, 0444, da9052_read_misc_channel, NULL,
			  DA9052_ADC_IN4);
static SENSOR_DEVICE_ATTR(in4_label, 0444, show_label, NULL,
			  DA9052_ADC_IN4);
static SENSOR_DEVICE_ATTR(in5_input, 0444, da9052_read_misc_channel, NULL,
			  DA9052_ADC_IN5);
static SENSOR_DEVICE_ATTR(in5_label, 0444, show_label, NULL,
			  DA9052_ADC_IN5);
static SENSOR_DEVICE_ATTR(in6_input, 0444, da9052_read_misc_channel, NULL,
			  DA9052_ADC_IN6);
static SENSOR_DEVICE_ATTR(in6_label, 0444, show_label, NULL,
			  DA9052_ADC_IN6);
static SENSOR_DEVICE_ATTR(in9_input, 0444, da9052_read_vbbat, NULL,
			  DA9052_ADC_VBBAT);
static SENSOR_DEVICE_ATTR(in9_label, 0444, show_label, NULL,
			  DA9052_ADC_VBBAT);

static SENSOR_DEVICE_ATTR(in70_input, 0444, da9052_read_tsi, NULL,
			  DA9052_ADC_TSI_XP);
static SENSOR_DEVICE_ATTR(in70_label, 0444, show_label, NULL,
			  DA9052_ADC_TSI_XP);
static SENSOR_DEVICE_ATTR(in71_input, 0444, da9052_read_tsi, NULL,
			  DA9052_ADC_TSI_XN);
static SENSOR_DEVICE_ATTR(in71_label, 0444, show_label, NULL,
			  DA9052_ADC_TSI_XN);
static SENSOR_DEVICE_ATTR(in72_input, 0444, da9052_read_tsi, NULL,
			  DA9052_ADC_TSI_YP);
static SENSOR_DEVICE_ATTR(in72_label, 0444, show_label, NULL,
			  DA9052_ADC_TSI_YP);
static SENSOR_DEVICE_ATTR(in73_input, 0444, da9052_read_tsi, NULL,
			  DA9052_ADC_TSI_YN);
static SENSOR_DEVICE_ATTR(in73_label, 0444, show_label, NULL,
			  DA9052_ADC_TSI_YN);

static SENSOR_DEVICE_ATTR(curr1_input, 0444, da9052_read_ich, NULL,
			  DA9052_ADC_ICH);
static SENSOR_DEVICE_ATTR(curr1_label, 0444, show_label, NULL,
			  DA9052_ADC_ICH);

static SENSOR_DEVICE_ATTR(temp2_input, 0444, da9052_read_tbat, NULL,
			  DA9052_ADC_TBAT);
static SENSOR_DEVICE_ATTR(temp2_label, 0444, show_label, NULL,
			  DA9052_ADC_TBAT);
static SENSOR_DEVICE_ATTR(temp8_input, 0444, da9052_read_tjunc, NULL,
			  DA9052_ADC_TJUNC);
static SENSOR_DEVICE_ATTR(temp8_label, 0444, show_label, NULL,
			  DA9052_ADC_TJUNC);

static struct attribute *da9052_attrs[] = {
	&sensor_dev_attr_in0_input.dev_attr.attr,
	&sensor_dev_attr_in0_label.dev_attr.attr,
	&sensor_dev_attr_in3_input.dev_attr.attr,
	&sensor_dev_attr_in3_label.dev_attr.attr,
	&sensor_dev_attr_in4_input.dev_attr.attr,
	&sensor_dev_attr_in4_label.dev_attr.attr,
	&sensor_dev_attr_in5_input.dev_attr.attr,
	&sensor_dev_attr_in5_label.dev_attr.attr,
	&sensor_dev_attr_in6_input.dev_attr.attr,
	&sensor_dev_attr_in6_label.dev_attr.attr,
	&sensor_dev_attr_in70_input.dev_attr.attr,
	&sensor_dev_attr_in70_label.dev_attr.attr,
	&sensor_dev_attr_in71_input.dev_attr.attr,
	&sensor_dev_attr_in71_label.dev_attr.attr,
	&sensor_dev_attr_in72_input.dev_attr.attr,
	&sensor_dev_attr_in72_label.dev_attr.attr,
	&sensor_dev_attr_in73_input.dev_attr.attr,
	&sensor_dev_attr_in73_label.dev_attr.attr,
	&sensor_dev_attr_in9_input.dev_attr.attr,
	&sensor_dev_attr_in9_label.dev_attr.attr,
	&sensor_dev_attr_curr1_input.dev_attr.attr,
	&sensor_dev_attr_curr1_label.dev_attr.attr,
	&sensor_dev_attr_temp2_input.dev_attr.attr,
	&sensor_dev_attr_temp2_label.dev_attr.attr,
	&sensor_dev_attr_temp8_input.dev_attr.attr,
	&sensor_dev_attr_temp8_label.dev_attr.attr,
	NULL
};

static const struct attribute_group da9052_group = {
	.attrs = da9052_attrs,
	.is_visible = da9052_channel_is_visible,
};
__ATTRIBUTE_GROUPS(da9052);

static irqreturn_t da9052_tsi_datardy_irq(int irq, void *data)
{
	struct da9052_hwmon *hwmon = data;

	complete(&hwmon->tsidone);
	return IRQ_HANDLED;
}

static int da9052_hwmon_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct da9052_hwmon *hwmon;
	struct device *hwmon_dev;
	int err;

	hwmon = devm_kzalloc(dev, sizeof(struct da9052_hwmon), GFP_KERNEL);
	if (!hwmon)
		return -ENOMEM;

	platform_set_drvdata(pdev, hwmon);

	mutex_init(&hwmon->hwmon_lock);
	hwmon->da9052 = dev_get_drvdata(pdev->dev.parent);

	init_completion(&hwmon->tsidone);

	hwmon->tsi_as_adc =
		device_property_read_bool(pdev->dev.parent, "dlg,tsi-as-adc");

	if (hwmon->tsi_as_adc) {
		hwmon->tsiref = devm_regulator_get(pdev->dev.parent, "tsiref");
		if (IS_ERR(hwmon->tsiref)) {
			err = PTR_ERR(hwmon->tsiref);
			dev_err(&pdev->dev, "failed to get tsiref: %d", err);
			return err;
		}

		err = regulator_enable(hwmon->tsiref);
		if (err)
			return err;

		hwmon->tsiref_mv = regulator_get_voltage(hwmon->tsiref);
		if (hwmon->tsiref_mv < 0) {
			err = hwmon->tsiref_mv;
			goto exit_regulator;
		}

		/* convert from microvolt (DT) to millivolt (hwmon) */
		hwmon->tsiref_mv /= 1000;

		/* TSIREF limits from datasheet */
		if (hwmon->tsiref_mv < 1800 || hwmon->tsiref_mv > 2600) {
			dev_err(hwmon->da9052->dev, "invalid TSIREF voltage: %d",
				hwmon->tsiref_mv);
			err = -ENXIO;
			goto exit_regulator;
		}

		/* disable touchscreen features */
		da9052_reg_write(hwmon->da9052, DA9052_TSI_CONT_A_REG, 0x00);

		/* Sample every 1ms */
		da9052_reg_update(hwmon->da9052, DA9052_ADC_CONT_REG,
					  DA9052_ADCCONT_ADCMODE,
					  DA9052_ADCCONT_ADCMODE);

		err = da9052_request_irq(hwmon->da9052, DA9052_IRQ_TSIREADY,
					 "tsiready-irq", da9052_tsi_datardy_irq,
					 hwmon);
		if (err) {
			dev_err(&pdev->dev, "Failed to register TSIRDY IRQ: %d",
				err);
			goto exit_regulator;
		}
	}

	hwmon_dev = devm_hwmon_device_register_with_groups(dev, "da9052",
							   hwmon,
							   da9052_groups);
	err = PTR_ERR_OR_ZERO(hwmon_dev);
	if (err)
		goto exit_irq;

	return 0;

exit_irq:
	if (hwmon->tsi_as_adc)
		da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
exit_regulator:
	if (hwmon->tsiref)
		regulator_disable(hwmon->tsiref);

	return err;
}

static int da9052_hwmon_remove(struct platform_device *pdev)
{
	struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);

	if (hwmon->tsi_as_adc) {
		da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
		regulator_disable(hwmon->tsiref);
	}

	return 0;
}

static struct platform_driver da9052_hwmon_driver = {
	.probe = da9052_hwmon_probe,
	.remove = da9052_hwmon_remove,
	.driver = {
		.name = "da9052-hwmon",
	},
};

module_platform_driver(da9052_hwmon_driver);

MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
MODULE_DESCRIPTION("DA9052 HWMON driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:da9052-hwmon");