1/*
2 * ADE7759 Active Energy Metering IC with di/dt Sensor Interface Driver
3 *
4 * Copyright 2010 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2 or later.
7 */
8
9#include <linux/interrupt.h>
10#include <linux/irq.h>
11#include <linux/delay.h>
12#include <linux/mutex.h>
13#include <linux/device.h>
14#include <linux/kernel.h>
15#include <linux/spi/spi.h>
16#include <linux/slab.h>
17#include <linux/sysfs.h>
18#include <linux/list.h>
19#include <linux/module.h>
20
21#include <linux/iio/iio.h>
22#include <linux/iio/sysfs.h>
23#include "meter.h"
24#include "ade7759.h"
25
26static int ade7759_spi_write_reg_8(struct device *dev,
27		u8 reg_address,
28		u8 val)
29{
30	int ret;
31	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
32	struct ade7759_state *st = iio_priv(indio_dev);
33
34	mutex_lock(&st->buf_lock);
35	st->tx[0] = ADE7759_WRITE_REG(reg_address);
36	st->tx[1] = val;
37
38	ret = spi_write(st->us, st->tx, 2);
39	mutex_unlock(&st->buf_lock);
40
41	return ret;
42}
43
44static int ade7759_spi_write_reg_16(struct device *dev,
45		u8 reg_address,
46		u16 value)
47{
48	int ret;
49	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
50	struct ade7759_state *st = iio_priv(indio_dev);
51
52	mutex_lock(&st->buf_lock);
53	st->tx[0] = ADE7759_WRITE_REG(reg_address);
54	st->tx[1] = (value >> 8) & 0xFF;
55	st->tx[2] = value & 0xFF;
56	ret = spi_write(st->us, st->tx, 3);
57	mutex_unlock(&st->buf_lock);
58
59	return ret;
60}
61
62static int ade7759_spi_read_reg_8(struct device *dev,
63		u8 reg_address,
64		u8 *val)
65{
66	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
67	struct ade7759_state *st = iio_priv(indio_dev);
68	int ret;
69
70	ret = spi_w8r8(st->us, ADE7759_READ_REG(reg_address));
71	if (ret < 0) {
72		dev_err(&st->us->dev, "problem when reading 8 bit register 0x%02X",
73				reg_address);
74		return ret;
75	}
76	*val = ret;
77
78	return 0;
79}
80
81static int ade7759_spi_read_reg_16(struct device *dev,
82		u8 reg_address,
83		u16 *val)
84{
85	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
86	struct ade7759_state *st = iio_priv(indio_dev);
87	int ret;
88
89	ret = spi_w8r16be(st->us, ADE7759_READ_REG(reg_address));
90	if (ret < 0) {
91		dev_err(&st->us->dev, "problem when reading 16 bit register 0x%02X",
92			reg_address);
93		return ret;
94	}
95
96	*val = ret;
97
98	return 0;
99}
100
101static int ade7759_spi_read_reg_40(struct device *dev,
102		u8 reg_address,
103		u64 *val)
104{
105	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
106	struct ade7759_state *st = iio_priv(indio_dev);
107	int ret;
108	struct spi_transfer xfers[] = {
109		{
110			.tx_buf = st->tx,
111			.rx_buf = st->rx,
112			.bits_per_word = 8,
113			.len = 6,
114		},
115	};
116
117	mutex_lock(&st->buf_lock);
118	st->tx[0] = ADE7759_READ_REG(reg_address);
119	memset(&st->tx[1], 0, 5);
120
121	ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
122	if (ret) {
123		dev_err(&st->us->dev, "problem when reading 40 bit register 0x%02X",
124				reg_address);
125		goto error_ret;
126	}
127	*val = ((u64)st->rx[1] << 32) | (st->rx[2] << 24) |
128		(st->rx[3] << 16) | (st->rx[4] << 8) | st->rx[5];
129
130error_ret:
131	mutex_unlock(&st->buf_lock);
132	return ret;
133}
134
135static ssize_t ade7759_read_8bit(struct device *dev,
136		struct device_attribute *attr,
137		char *buf)
138{
139	int ret;
140	u8 val = 0;
141	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
142
143	ret = ade7759_spi_read_reg_8(dev, this_attr->address, &val);
144	if (ret)
145		return ret;
146
147	return sprintf(buf, "%u\n", val);
148}
149
150static ssize_t ade7759_read_16bit(struct device *dev,
151		struct device_attribute *attr,
152		char *buf)
153{
154	int ret;
155	u16 val = 0;
156	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
157
158	ret = ade7759_spi_read_reg_16(dev, this_attr->address, &val);
159	if (ret)
160		return ret;
161
162	return sprintf(buf, "%u\n", val);
163}
164
165static ssize_t ade7759_read_40bit(struct device *dev,
166		struct device_attribute *attr,
167		char *buf)
168{
169	int ret;
170	u64 val = 0;
171	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
172
173	ret = ade7759_spi_read_reg_40(dev, this_attr->address, &val);
174	if (ret)
175		return ret;
176
177	return sprintf(buf, "%llu\n", val);
178}
179
180static ssize_t ade7759_write_8bit(struct device *dev,
181		struct device_attribute *attr,
182		const char *buf,
183		size_t len)
184{
185	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
186	int ret;
187	u8 val;
188
189	ret = kstrtou8(buf, 10, &val);
190	if (ret)
191		goto error_ret;
192	ret = ade7759_spi_write_reg_8(dev, this_attr->address, val);
193
194error_ret:
195	return ret ? ret : len;
196}
197
198static ssize_t ade7759_write_16bit(struct device *dev,
199		struct device_attribute *attr,
200		const char *buf,
201		size_t len)
202{
203	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
204	int ret;
205	u16 val;
206
207	ret = kstrtou16(buf, 10, &val);
208	if (ret)
209		goto error_ret;
210	ret = ade7759_spi_write_reg_16(dev, this_attr->address, val);
211
212error_ret:
213	return ret ? ret : len;
214}
215
216static int ade7759_reset(struct device *dev)
217{
218	int ret;
219	u16 val;
220
221	ret = ade7759_spi_read_reg_16(dev,
222			ADE7759_MODE,
223			&val);
224	if (ret < 0)
225		return ret;
226
227	val |= 1 << 6; /* Software Chip Reset */
228	return ade7759_spi_write_reg_16(dev,
229			ADE7759_MODE,
230			val);
231}
232
233static IIO_DEV_ATTR_AENERGY(ade7759_read_40bit, ADE7759_AENERGY);
234static IIO_DEV_ATTR_CFDEN(S_IWUSR | S_IRUGO,
235		ade7759_read_16bit,
236		ade7759_write_16bit,
237		ADE7759_CFDEN);
238static IIO_DEV_ATTR_CFNUM(S_IWUSR | S_IRUGO,
239		ade7759_read_8bit,
240		ade7759_write_8bit,
241		ADE7759_CFNUM);
242static IIO_DEV_ATTR_CHKSUM(ade7759_read_8bit, ADE7759_CHKSUM);
243static IIO_DEV_ATTR_PHCAL(S_IWUSR | S_IRUGO,
244		ade7759_read_16bit,
245		ade7759_write_16bit,
246		ADE7759_PHCAL);
247static IIO_DEV_ATTR_APOS(S_IWUSR | S_IRUGO,
248		ade7759_read_16bit,
249		ade7759_write_16bit,
250		ADE7759_APOS);
251static IIO_DEV_ATTR_SAGCYC(S_IWUSR | S_IRUGO,
252		ade7759_read_8bit,
253		ade7759_write_8bit,
254		ADE7759_SAGCYC);
255static IIO_DEV_ATTR_SAGLVL(S_IWUSR | S_IRUGO,
256		ade7759_read_8bit,
257		ade7759_write_8bit,
258		ADE7759_SAGLVL);
259static IIO_DEV_ATTR_LINECYC(S_IWUSR | S_IRUGO,
260		ade7759_read_8bit,
261		ade7759_write_8bit,
262		ADE7759_LINECYC);
263static IIO_DEV_ATTR_LENERGY(ade7759_read_40bit, ADE7759_LENERGY);
264static IIO_DEV_ATTR_PGA_GAIN(S_IWUSR | S_IRUGO,
265		ade7759_read_8bit,
266		ade7759_write_8bit,
267		ADE7759_GAIN);
268static IIO_DEV_ATTR_ACTIVE_POWER_GAIN(S_IWUSR | S_IRUGO,
269		ade7759_read_16bit,
270		ade7759_write_16bit,
271		ADE7759_APGAIN);
272static IIO_DEV_ATTR_CH_OFF(1, S_IWUSR | S_IRUGO,
273		ade7759_read_8bit,
274		ade7759_write_8bit,
275		ADE7759_CH1OS);
276static IIO_DEV_ATTR_CH_OFF(2, S_IWUSR | S_IRUGO,
277		ade7759_read_8bit,
278		ade7759_write_8bit,
279		ADE7759_CH2OS);
280
281static int ade7759_set_irq(struct device *dev, bool enable)
282{
283	int ret;
284	u8 irqen;
285
286	ret = ade7759_spi_read_reg_8(dev, ADE7759_IRQEN, &irqen);
287	if (ret)
288		goto error_ret;
289
290	if (enable)
291		irqen |= 1 << 3; /* Enables an interrupt when a data is
292				    present in the waveform register */
293	else
294		irqen &= ~(1 << 3);
295
296	ret = ade7759_spi_write_reg_8(dev, ADE7759_IRQEN, irqen);
297
298error_ret:
299	return ret;
300}
301
302/* Power down the device */
303static int ade7759_stop_device(struct device *dev)
304{
305	int ret;
306	u16 val;
307
308	ret = ade7759_spi_read_reg_16(dev,
309			ADE7759_MODE,
310			&val);
311	if (ret < 0) {
312		dev_err(dev, "unable to power down the device, error: %d\n",
313			ret);
314		return ret;
315	}
316
317	val |= 1 << 4;  /* AD converters can be turned off */
318
319	return ade7759_spi_write_reg_16(dev, ADE7759_MODE, val);
320}
321
322static int ade7759_initial_setup(struct iio_dev *indio_dev)
323{
324	int ret;
325	struct ade7759_state *st = iio_priv(indio_dev);
326	struct device *dev = &indio_dev->dev;
327
328	/* use low spi speed for init */
329	st->us->mode = SPI_MODE_3;
330	spi_setup(st->us);
331
332	/* Disable IRQ */
333	ret = ade7759_set_irq(dev, false);
334	if (ret) {
335		dev_err(dev, "disable irq failed");
336		goto err_ret;
337	}
338
339	ade7759_reset(dev);
340	msleep(ADE7759_STARTUP_DELAY);
341
342err_ret:
343	return ret;
344}
345
346static ssize_t ade7759_read_frequency(struct device *dev,
347		struct device_attribute *attr,
348		char *buf)
349{
350	int ret;
351	u16 t;
352	int sps;
353
354	ret = ade7759_spi_read_reg_16(dev,
355			ADE7759_MODE,
356			&t);
357	if (ret)
358		return ret;
359
360	t = (t >> 3) & 0x3;
361	sps = 27900 / (1 + t);
362
363	return sprintf(buf, "%d\n", sps);
364}
365
366static ssize_t ade7759_write_frequency(struct device *dev,
367		struct device_attribute *attr,
368		const char *buf,
369		size_t len)
370{
371	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
372	struct ade7759_state *st = iio_priv(indio_dev);
373	u16 val;
374	int ret;
375	u16 reg, t;
376
377	ret = kstrtou16(buf, 10, &val);
378	if (ret)
379		return ret;
380	if (val == 0)
381		return -EINVAL;
382
383	mutex_lock(&indio_dev->mlock);
384
385	t = 27900 / val;
386	if (t > 0)
387		t--;
388
389	if (t > 1)
390		st->us->max_speed_hz = ADE7759_SPI_SLOW;
391	else
392		st->us->max_speed_hz = ADE7759_SPI_FAST;
393
394	ret = ade7759_spi_read_reg_16(dev, ADE7759_MODE, &reg);
395	if (ret)
396		goto out;
397
398	reg &= ~(3 << 13);
399	reg |= t << 13;
400
401	ret = ade7759_spi_write_reg_16(dev, ADE7759_MODE, reg);
402
403out:
404	mutex_unlock(&indio_dev->mlock);
405
406	return ret ? ret : len;
407}
408static IIO_DEV_ATTR_TEMP_RAW(ade7759_read_8bit);
409static IIO_CONST_ATTR(in_temp_offset, "70 C");
410static IIO_CONST_ATTR(in_temp_scale, "1 C");
411
412static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
413		ade7759_read_frequency,
414		ade7759_write_frequency);
415
416static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("27900 14000 7000 3500");
417
418static struct attribute *ade7759_attributes[] = {
419	&iio_dev_attr_in_temp_raw.dev_attr.attr,
420	&iio_const_attr_in_temp_offset.dev_attr.attr,
421	&iio_const_attr_in_temp_scale.dev_attr.attr,
422	&iio_dev_attr_sampling_frequency.dev_attr.attr,
423	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
424	&iio_dev_attr_phcal.dev_attr.attr,
425	&iio_dev_attr_cfden.dev_attr.attr,
426	&iio_dev_attr_aenergy.dev_attr.attr,
427	&iio_dev_attr_cfnum.dev_attr.attr,
428	&iio_dev_attr_apos.dev_attr.attr,
429	&iio_dev_attr_sagcyc.dev_attr.attr,
430	&iio_dev_attr_saglvl.dev_attr.attr,
431	&iio_dev_attr_linecyc.dev_attr.attr,
432	&iio_dev_attr_lenergy.dev_attr.attr,
433	&iio_dev_attr_chksum.dev_attr.attr,
434	&iio_dev_attr_pga_gain.dev_attr.attr,
435	&iio_dev_attr_active_power_gain.dev_attr.attr,
436	&iio_dev_attr_choff_1.dev_attr.attr,
437	&iio_dev_attr_choff_2.dev_attr.attr,
438	NULL,
439};
440
441static const struct attribute_group ade7759_attribute_group = {
442	.attrs = ade7759_attributes,
443};
444
445static const struct iio_info ade7759_info = {
446	.attrs = &ade7759_attribute_group,
447	.driver_module = THIS_MODULE,
448};
449
450static int ade7759_probe(struct spi_device *spi)
451{
452	int ret;
453	struct ade7759_state *st;
454	struct iio_dev *indio_dev;
455
456	/* setup the industrialio driver allocated elements */
457	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
458	if (!indio_dev)
459		return -ENOMEM;
460	/* this is only used for removal purposes */
461	spi_set_drvdata(spi, indio_dev);
462
463	st = iio_priv(indio_dev);
464	st->us = spi;
465	mutex_init(&st->buf_lock);
466	indio_dev->name = spi->dev.driver->name;
467	indio_dev->dev.parent = &spi->dev;
468	indio_dev->info = &ade7759_info;
469	indio_dev->modes = INDIO_DIRECT_MODE;
470
471	/* Get the device into a sane initial state */
472	ret = ade7759_initial_setup(indio_dev);
473	if (ret)
474		return ret;
475
476	return iio_device_register(indio_dev);
477}
478
479/* fixme, confirm ordering in this function */
480static int ade7759_remove(struct spi_device *spi)
481{
482	struct iio_dev *indio_dev = spi_get_drvdata(spi);
483
484	iio_device_unregister(indio_dev);
485	ade7759_stop_device(&indio_dev->dev);
486
487	return 0;
488}
489
490static struct spi_driver ade7759_driver = {
491	.driver = {
492		.name = "ade7759",
493		.owner = THIS_MODULE,
494	},
495	.probe = ade7759_probe,
496	.remove = ade7759_remove,
497};
498module_spi_driver(ade7759_driver);
499
500MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
501MODULE_DESCRIPTION("Analog Devices ADE7759 Active Energy Metering IC Driver");
502MODULE_LICENSE("GPL v2");
503MODULE_ALIAS("spi:ad7759");
504