1/*
2 * HID Sensors Driver
3 * Copyright (c) 2014, Intel Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program.
16 *
17 */
18#include <linux/device.h>
19#include <linux/platform_device.h>
20#include <linux/module.h>
21#include <linux/interrupt.h>
22#include <linux/irq.h>
23#include <linux/slab.h>
24#include <linux/delay.h>
25#include <linux/hid-sensor-hub.h>
26#include <linux/iio/iio.h>
27#include <linux/iio/sysfs.h>
28#include <linux/iio/buffer.h>
29#include <linux/iio/trigger_consumer.h>
30#include <linux/iio/triggered_buffer.h>
31#include "../common/hid-sensors/hid-sensor-trigger.h"
32
33#define CHANNEL_SCAN_INDEX_PRESENCE 0
34
35struct prox_state {
36	struct hid_sensor_hub_callbacks callbacks;
37	struct hid_sensor_common common_attributes;
38	struct hid_sensor_hub_attribute_info prox_attr;
39	u32 human_presence;
40};
41
42/* Channel definitions */
43static const struct iio_chan_spec prox_channels[] = {
44	{
45		.type = IIO_PROXIMITY,
46		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
47		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
48		BIT(IIO_CHAN_INFO_SCALE) |
49		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
50		BIT(IIO_CHAN_INFO_HYSTERESIS),
51		.scan_index = CHANNEL_SCAN_INDEX_PRESENCE,
52	}
53};
54
55/* Adjust channel real bits based on report descriptor */
56static void prox_adjust_channel_bit_mask(struct iio_chan_spec *channels,
57					int channel, int size)
58{
59	channels[channel].scan_type.sign = 's';
60	/* Real storage bits will change based on the report desc. */
61	channels[channel].scan_type.realbits = size * 8;
62	/* Maximum size of a sample to capture is u32 */
63	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
64}
65
66/* Channel read_raw handler */
67static int prox_read_raw(struct iio_dev *indio_dev,
68			      struct iio_chan_spec const *chan,
69			      int *val, int *val2,
70			      long mask)
71{
72	struct prox_state *prox_state = iio_priv(indio_dev);
73	int report_id = -1;
74	u32 address;
75	int ret_type;
76
77	*val = 0;
78	*val2 = 0;
79	switch (mask) {
80	case IIO_CHAN_INFO_RAW:
81		switch (chan->scan_index) {
82		case  CHANNEL_SCAN_INDEX_PRESENCE:
83			report_id = prox_state->prox_attr.report_id;
84			address =
85			HID_USAGE_SENSOR_HUMAN_PRESENCE;
86			break;
87		default:
88			report_id = -1;
89			break;
90		}
91		if (report_id >= 0) {
92			hid_sensor_power_state(&prox_state->common_attributes,
93						true);
94			*val = sensor_hub_input_attr_get_raw_value(
95				prox_state->common_attributes.hsdev,
96				HID_USAGE_SENSOR_PROX, address,
97				report_id,
98				SENSOR_HUB_SYNC);
99			hid_sensor_power_state(&prox_state->common_attributes,
100						false);
101		} else {
102			*val = 0;
103			return -EINVAL;
104		}
105		ret_type = IIO_VAL_INT;
106		break;
107	case IIO_CHAN_INFO_SCALE:
108		*val = prox_state->prox_attr.units;
109		ret_type = IIO_VAL_INT;
110		break;
111	case IIO_CHAN_INFO_OFFSET:
112		*val = hid_sensor_convert_exponent(
113				prox_state->prox_attr.unit_expo);
114		ret_type = IIO_VAL_INT;
115		break;
116	case IIO_CHAN_INFO_SAMP_FREQ:
117		ret_type = hid_sensor_read_samp_freq_value(
118				&prox_state->common_attributes, val, val2);
119		break;
120	case IIO_CHAN_INFO_HYSTERESIS:
121		ret_type = hid_sensor_read_raw_hyst_value(
122				&prox_state->common_attributes, val, val2);
123		break;
124	default:
125		ret_type = -EINVAL;
126		break;
127	}
128
129	return ret_type;
130}
131
132/* Channel write_raw handler */
133static int prox_write_raw(struct iio_dev *indio_dev,
134			       struct iio_chan_spec const *chan,
135			       int val,
136			       int val2,
137			       long mask)
138{
139	struct prox_state *prox_state = iio_priv(indio_dev);
140	int ret = 0;
141
142	switch (mask) {
143	case IIO_CHAN_INFO_SAMP_FREQ:
144		ret = hid_sensor_write_samp_freq_value(
145				&prox_state->common_attributes, val, val2);
146		break;
147	case IIO_CHAN_INFO_HYSTERESIS:
148		ret = hid_sensor_write_raw_hyst_value(
149				&prox_state->common_attributes, val, val2);
150		break;
151	default:
152		ret = -EINVAL;
153	}
154
155	return ret;
156}
157
158static const struct iio_info prox_info = {
159	.driver_module = THIS_MODULE,
160	.read_raw = &prox_read_raw,
161	.write_raw = &prox_write_raw,
162};
163
164/* Function to push data to buffer */
165static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
166					int len)
167{
168	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
169	iio_push_to_buffers(indio_dev, data);
170}
171
172/* Callback handler to send event after all samples are received and captured */
173static int prox_proc_event(struct hid_sensor_hub_device *hsdev,
174				unsigned usage_id,
175				void *priv)
176{
177	struct iio_dev *indio_dev = platform_get_drvdata(priv);
178	struct prox_state *prox_state = iio_priv(indio_dev);
179
180	dev_dbg(&indio_dev->dev, "prox_proc_event\n");
181	if (atomic_read(&prox_state->common_attributes.data_ready))
182		hid_sensor_push_data(indio_dev,
183				&prox_state->human_presence,
184				sizeof(prox_state->human_presence));
185
186	return 0;
187}
188
189/* Capture samples in local storage */
190static int prox_capture_sample(struct hid_sensor_hub_device *hsdev,
191				unsigned usage_id,
192				size_t raw_len, char *raw_data,
193				void *priv)
194{
195	struct iio_dev *indio_dev = platform_get_drvdata(priv);
196	struct prox_state *prox_state = iio_priv(indio_dev);
197	int ret = -EINVAL;
198
199	switch (usage_id) {
200	case HID_USAGE_SENSOR_HUMAN_PRESENCE:
201		prox_state->human_presence = *(u32 *)raw_data;
202		ret = 0;
203		break;
204	default:
205		break;
206	}
207
208	return ret;
209}
210
211/* Parse report which is specific to an usage id*/
212static int prox_parse_report(struct platform_device *pdev,
213				struct hid_sensor_hub_device *hsdev,
214				struct iio_chan_spec *channels,
215				unsigned usage_id,
216				struct prox_state *st)
217{
218	int ret;
219
220	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
221			usage_id,
222			HID_USAGE_SENSOR_HUMAN_PRESENCE,
223			&st->prox_attr);
224	if (ret < 0)
225		return ret;
226	prox_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESENCE,
227					st->prox_attr.size);
228
229	dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr.index,
230			st->prox_attr.report_id);
231
232	/* Set Sensitivity field ids, when there is no individual modifier */
233	if (st->common_attributes.sensitivity.index < 0) {
234		sensor_hub_input_get_attribute_info(hsdev,
235			HID_FEATURE_REPORT, usage_id,
236			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
237			HID_USAGE_SENSOR_DATA_PRESENCE,
238			&st->common_attributes.sensitivity);
239		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
240			st->common_attributes.sensitivity.index,
241			st->common_attributes.sensitivity.report_id);
242	}
243	return ret;
244}
245
246/* Function to initialize the processing for usage id */
247static int hid_prox_probe(struct platform_device *pdev)
248{
249	int ret = 0;
250	static const char *name = "prox";
251	struct iio_dev *indio_dev;
252	struct prox_state *prox_state;
253	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
254
255	indio_dev = devm_iio_device_alloc(&pdev->dev,
256				sizeof(struct prox_state));
257	if (!indio_dev)
258		return -ENOMEM;
259	platform_set_drvdata(pdev, indio_dev);
260
261	prox_state = iio_priv(indio_dev);
262	prox_state->common_attributes.hsdev = hsdev;
263	prox_state->common_attributes.pdev = pdev;
264
265	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_PROX,
266					&prox_state->common_attributes);
267	if (ret) {
268		dev_err(&pdev->dev, "failed to setup common attributes\n");
269		return ret;
270	}
271
272	indio_dev->channels = kmemdup(prox_channels, sizeof(prox_channels),
273				      GFP_KERNEL);
274	if (!indio_dev->channels) {
275		dev_err(&pdev->dev, "failed to duplicate channels\n");
276		return -ENOMEM;
277	}
278
279	ret = prox_parse_report(pdev, hsdev,
280				(struct iio_chan_spec *)indio_dev->channels,
281				HID_USAGE_SENSOR_PROX, prox_state);
282	if (ret) {
283		dev_err(&pdev->dev, "failed to setup attributes\n");
284		goto error_free_dev_mem;
285	}
286
287	indio_dev->num_channels =
288				ARRAY_SIZE(prox_channels);
289	indio_dev->dev.parent = &pdev->dev;
290	indio_dev->info = &prox_info;
291	indio_dev->name = name;
292	indio_dev->modes = INDIO_DIRECT_MODE;
293
294	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
295		NULL, NULL);
296	if (ret) {
297		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
298		goto error_free_dev_mem;
299	}
300	atomic_set(&prox_state->common_attributes.data_ready, 0);
301	ret = hid_sensor_setup_trigger(indio_dev, name,
302				&prox_state->common_attributes);
303	if (ret) {
304		dev_err(&pdev->dev, "trigger setup failed\n");
305		goto error_unreg_buffer_funcs;
306	}
307
308	ret = iio_device_register(indio_dev);
309	if (ret) {
310		dev_err(&pdev->dev, "device register failed\n");
311		goto error_remove_trigger;
312	}
313
314	prox_state->callbacks.send_event = prox_proc_event;
315	prox_state->callbacks.capture_sample = prox_capture_sample;
316	prox_state->callbacks.pdev = pdev;
317	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_PROX,
318					&prox_state->callbacks);
319	if (ret < 0) {
320		dev_err(&pdev->dev, "callback reg failed\n");
321		goto error_iio_unreg;
322	}
323
324	return ret;
325
326error_iio_unreg:
327	iio_device_unregister(indio_dev);
328error_remove_trigger:
329	hid_sensor_remove_trigger(&prox_state->common_attributes);
330error_unreg_buffer_funcs:
331	iio_triggered_buffer_cleanup(indio_dev);
332error_free_dev_mem:
333	kfree(indio_dev->channels);
334	return ret;
335}
336
337/* Function to deinitialize the processing for usage id */
338static int hid_prox_remove(struct platform_device *pdev)
339{
340	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
341	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
342	struct prox_state *prox_state = iio_priv(indio_dev);
343
344	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_PROX);
345	iio_device_unregister(indio_dev);
346	hid_sensor_remove_trigger(&prox_state->common_attributes);
347	iio_triggered_buffer_cleanup(indio_dev);
348	kfree(indio_dev->channels);
349
350	return 0;
351}
352
353static struct platform_device_id hid_prox_ids[] = {
354	{
355		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
356		.name = "HID-SENSOR-200011",
357	},
358	{ /* sentinel */ }
359};
360MODULE_DEVICE_TABLE(platform, hid_prox_ids);
361
362static struct platform_driver hid_prox_platform_driver = {
363	.id_table = hid_prox_ids,
364	.driver = {
365		.name	= KBUILD_MODNAME,
366		.pm	= &hid_sensor_pm_ops,
367	},
368	.probe		= hid_prox_probe,
369	.remove		= hid_prox_remove,
370};
371module_platform_driver(hid_prox_platform_driver);
372
373MODULE_DESCRIPTION("HID Sensor Proximity");
374MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
375MODULE_LICENSE("GPL");
376