1/*
2 * HID Sensors Driver
3 * Copyright (c) 2012, 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; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 */
19#include <linux/device.h>
20#include <linux/platform_device.h>
21#include <linux/module.h>
22#include <linux/interrupt.h>
23#include <linux/irq.h>
24#include <linux/slab.h>
25#include <linux/delay.h>
26#include <linux/hid-sensor-hub.h>
27#include <linux/iio/iio.h>
28#include <linux/iio/sysfs.h>
29#include <linux/iio/buffer.h>
30#include <linux/iio/trigger_consumer.h>
31#include <linux/iio/triggered_buffer.h>
32#include "../common/hid-sensors/hid-sensor-trigger.h"
33
34#define CHANNEL_SCAN_INDEX_ILLUM 0
35
36struct als_state {
37	struct hid_sensor_hub_callbacks callbacks;
38	struct hid_sensor_common common_attributes;
39	struct hid_sensor_hub_attribute_info als_illum;
40	u32 illum;
41	int scale_pre_decml;
42	int scale_post_decml;
43	int scale_precision;
44	int value_offset;
45};
46
47/* Channel definitions */
48static const struct iio_chan_spec als_channels[] = {
49	{
50		.type = IIO_INTENSITY,
51		.modified = 1,
52		.channel2 = IIO_MOD_LIGHT_BOTH,
53		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
54		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
55		BIT(IIO_CHAN_INFO_SCALE) |
56		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
57		BIT(IIO_CHAN_INFO_HYSTERESIS),
58		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
59	}
60};
61
62/* Adjust channel real bits based on report descriptor */
63static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
64					int channel, int size)
65{
66	channels[channel].scan_type.sign = 's';
67	/* Real storage bits will change based on the report desc. */
68	channels[channel].scan_type.realbits = size * 8;
69	/* Maximum size of a sample to capture is u32 */
70	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
71}
72
73/* Channel read_raw handler */
74static int als_read_raw(struct iio_dev *indio_dev,
75			      struct iio_chan_spec const *chan,
76			      int *val, int *val2,
77			      long mask)
78{
79	struct als_state *als_state = iio_priv(indio_dev);
80	int report_id = -1;
81	u32 address;
82	int ret_type;
83
84	*val = 0;
85	*val2 = 0;
86	switch (mask) {
87	case 0:
88		switch (chan->scan_index) {
89		case  CHANNEL_SCAN_INDEX_ILLUM:
90			report_id = als_state->als_illum.report_id;
91			address =
92			HID_USAGE_SENSOR_LIGHT_ILLUM;
93			break;
94		default:
95			report_id = -1;
96			break;
97		}
98		if (report_id >= 0) {
99			hid_sensor_power_state(&als_state->common_attributes,
100						true);
101			*val = sensor_hub_input_attr_get_raw_value(
102					als_state->common_attributes.hsdev,
103					HID_USAGE_SENSOR_ALS, address,
104					report_id,
105					SENSOR_HUB_SYNC);
106			hid_sensor_power_state(&als_state->common_attributes,
107						false);
108		} else {
109			*val = 0;
110			return -EINVAL;
111		}
112		ret_type = IIO_VAL_INT;
113		break;
114	case IIO_CHAN_INFO_SCALE:
115		*val = als_state->scale_pre_decml;
116		*val2 = als_state->scale_post_decml;
117		ret_type = als_state->scale_precision;
118		break;
119	case IIO_CHAN_INFO_OFFSET:
120		*val = als_state->value_offset;
121		ret_type = IIO_VAL_INT;
122		break;
123	case IIO_CHAN_INFO_SAMP_FREQ:
124		ret_type = hid_sensor_read_samp_freq_value(
125				&als_state->common_attributes, val, val2);
126		break;
127	case IIO_CHAN_INFO_HYSTERESIS:
128		ret_type = hid_sensor_read_raw_hyst_value(
129				&als_state->common_attributes, val, val2);
130		break;
131	default:
132		ret_type = -EINVAL;
133		break;
134	}
135
136	return ret_type;
137}
138
139/* Channel write_raw handler */
140static int als_write_raw(struct iio_dev *indio_dev,
141			       struct iio_chan_spec const *chan,
142			       int val,
143			       int val2,
144			       long mask)
145{
146	struct als_state *als_state = iio_priv(indio_dev);
147	int ret = 0;
148
149	switch (mask) {
150	case IIO_CHAN_INFO_SAMP_FREQ:
151		ret = hid_sensor_write_samp_freq_value(
152				&als_state->common_attributes, val, val2);
153		break;
154	case IIO_CHAN_INFO_HYSTERESIS:
155		ret = hid_sensor_write_raw_hyst_value(
156				&als_state->common_attributes, val, val2);
157		break;
158	default:
159		ret = -EINVAL;
160	}
161
162	return ret;
163}
164
165static const struct iio_info als_info = {
166	.driver_module = THIS_MODULE,
167	.read_raw = &als_read_raw,
168	.write_raw = &als_write_raw,
169};
170
171/* Function to push data to buffer */
172static void hid_sensor_push_data(struct iio_dev *indio_dev, const void *data,
173					int len)
174{
175	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
176	iio_push_to_buffers(indio_dev, data);
177}
178
179/* Callback handler to send event after all samples are received and captured */
180static int als_proc_event(struct hid_sensor_hub_device *hsdev,
181				unsigned usage_id,
182				void *priv)
183{
184	struct iio_dev *indio_dev = platform_get_drvdata(priv);
185	struct als_state *als_state = iio_priv(indio_dev);
186
187	dev_dbg(&indio_dev->dev, "als_proc_event\n");
188	if (atomic_read(&als_state->common_attributes.data_ready))
189		hid_sensor_push_data(indio_dev,
190				&als_state->illum,
191				sizeof(als_state->illum));
192
193	return 0;
194}
195
196/* Capture samples in local storage */
197static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
198				unsigned usage_id,
199				size_t raw_len, char *raw_data,
200				void *priv)
201{
202	struct iio_dev *indio_dev = platform_get_drvdata(priv);
203	struct als_state *als_state = iio_priv(indio_dev);
204	int ret = -EINVAL;
205
206	switch (usage_id) {
207	case HID_USAGE_SENSOR_LIGHT_ILLUM:
208		als_state->illum = *(u32 *)raw_data;
209		ret = 0;
210		break;
211	default:
212		break;
213	}
214
215	return ret;
216}
217
218/* Parse report which is specific to an usage id*/
219static int als_parse_report(struct platform_device *pdev,
220				struct hid_sensor_hub_device *hsdev,
221				struct iio_chan_spec *channels,
222				unsigned usage_id,
223				struct als_state *st)
224{
225	int ret;
226
227	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
228			usage_id,
229			HID_USAGE_SENSOR_LIGHT_ILLUM,
230			&st->als_illum);
231	if (ret < 0)
232		return ret;
233	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
234					st->als_illum.size);
235
236	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
237			st->als_illum.report_id);
238
239	st->scale_precision = hid_sensor_format_scale(
240				HID_USAGE_SENSOR_ALS,
241				&st->als_illum,
242				&st->scale_pre_decml, &st->scale_post_decml);
243
244	/* Set Sensitivity field ids, when there is no individual modifier */
245	if (st->common_attributes.sensitivity.index < 0) {
246		sensor_hub_input_get_attribute_info(hsdev,
247			HID_FEATURE_REPORT, usage_id,
248			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
249			HID_USAGE_SENSOR_DATA_LIGHT,
250			&st->common_attributes.sensitivity);
251		dev_dbg(&pdev->dev, "Sensitivity index:report %d:%d\n",
252			st->common_attributes.sensitivity.index,
253			st->common_attributes.sensitivity.report_id);
254	}
255	return ret;
256}
257
258/* Function to initialize the processing for usage id */
259static int hid_als_probe(struct platform_device *pdev)
260{
261	int ret = 0;
262	static const char *name = "als";
263	struct iio_dev *indio_dev;
264	struct als_state *als_state;
265	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
266
267	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct als_state));
268	if (!indio_dev)
269		return -ENOMEM;
270	platform_set_drvdata(pdev, indio_dev);
271
272	als_state = iio_priv(indio_dev);
273	als_state->common_attributes.hsdev = hsdev;
274	als_state->common_attributes.pdev = pdev;
275
276	ret = hid_sensor_parse_common_attributes(hsdev, HID_USAGE_SENSOR_ALS,
277					&als_state->common_attributes);
278	if (ret) {
279		dev_err(&pdev->dev, "failed to setup common attributes\n");
280		return ret;
281	}
282
283	indio_dev->channels = kmemdup(als_channels,
284				      sizeof(als_channels), GFP_KERNEL);
285	if (!indio_dev->channels) {
286		dev_err(&pdev->dev, "failed to duplicate channels\n");
287		return -ENOMEM;
288	}
289
290	ret = als_parse_report(pdev, hsdev,
291			       (struct iio_chan_spec *)indio_dev->channels,
292			       HID_USAGE_SENSOR_ALS, als_state);
293	if (ret) {
294		dev_err(&pdev->dev, "failed to setup attributes\n");
295		goto error_free_dev_mem;
296	}
297
298	indio_dev->num_channels =
299				ARRAY_SIZE(als_channels);
300	indio_dev->dev.parent = &pdev->dev;
301	indio_dev->info = &als_info;
302	indio_dev->name = name;
303	indio_dev->modes = INDIO_DIRECT_MODE;
304
305	ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
306		NULL, NULL);
307	if (ret) {
308		dev_err(&pdev->dev, "failed to initialize trigger buffer\n");
309		goto error_free_dev_mem;
310	}
311	atomic_set(&als_state->common_attributes.data_ready, 0);
312	ret = hid_sensor_setup_trigger(indio_dev, name,
313				&als_state->common_attributes);
314	if (ret < 0) {
315		dev_err(&pdev->dev, "trigger setup failed\n");
316		goto error_unreg_buffer_funcs;
317	}
318
319	ret = iio_device_register(indio_dev);
320	if (ret) {
321		dev_err(&pdev->dev, "device register failed\n");
322		goto error_remove_trigger;
323	}
324
325	als_state->callbacks.send_event = als_proc_event;
326	als_state->callbacks.capture_sample = als_capture_sample;
327	als_state->callbacks.pdev = pdev;
328	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_ALS,
329					&als_state->callbacks);
330	if (ret < 0) {
331		dev_err(&pdev->dev, "callback reg failed\n");
332		goto error_iio_unreg;
333	}
334
335	return ret;
336
337error_iio_unreg:
338	iio_device_unregister(indio_dev);
339error_remove_trigger:
340	hid_sensor_remove_trigger(&als_state->common_attributes);
341error_unreg_buffer_funcs:
342	iio_triggered_buffer_cleanup(indio_dev);
343error_free_dev_mem:
344	kfree(indio_dev->channels);
345	return ret;
346}
347
348/* Function to deinitialize the processing for usage id */
349static int hid_als_remove(struct platform_device *pdev)
350{
351	struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
352	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
353	struct als_state *als_state = iio_priv(indio_dev);
354
355	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_ALS);
356	iio_device_unregister(indio_dev);
357	hid_sensor_remove_trigger(&als_state->common_attributes);
358	iio_triggered_buffer_cleanup(indio_dev);
359	kfree(indio_dev->channels);
360
361	return 0;
362}
363
364static const struct platform_device_id hid_als_ids[] = {
365	{
366		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
367		.name = "HID-SENSOR-200041",
368	},
369	{ /* sentinel */ }
370};
371MODULE_DEVICE_TABLE(platform, hid_als_ids);
372
373static struct platform_driver hid_als_platform_driver = {
374	.id_table = hid_als_ids,
375	.driver = {
376		.name	= KBUILD_MODNAME,
377		.pm	= &hid_sensor_pm_ops,
378	},
379	.probe		= hid_als_probe,
380	.remove		= hid_als_remove,
381};
382module_platform_driver(hid_als_platform_driver);
383
384MODULE_DESCRIPTION("HID Sensor ALS");
385MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
386MODULE_LICENSE("GPL");
387