1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * HID Sensors Driver
4 * Copyright (c) 2017, Intel Corporation.
5 */
6#include <linux/device.h>
7#include <linux/hid-sensor-hub.h>
8#include <linux/iio/buffer.h>
9#include <linux/iio/iio.h>
10#include <linux/module.h>
11#include <linux/platform_device.h>
12
13#include "../common/hid-sensors/hid-sensor-trigger.h"
14
15struct temperature_state {
16	struct hid_sensor_common common_attributes;
17	struct hid_sensor_hub_attribute_info temperature_attr;
18	struct {
19		s32 temperature_data;
20		u64 timestamp __aligned(8);
21	} scan;
22	int scale_pre_decml;
23	int scale_post_decml;
24	int scale_precision;
25	int value_offset;
26};
27
28/* Channel definitions */
29static const struct iio_chan_spec temperature_channels[] = {
30	{
31		.type = IIO_TEMP,
32		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
33		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
34			BIT(IIO_CHAN_INFO_SCALE) |
35			BIT(IIO_CHAN_INFO_SAMP_FREQ) |
36			BIT(IIO_CHAN_INFO_HYSTERESIS),
37	},
38	IIO_CHAN_SOFT_TIMESTAMP(1),
39};
40
41/* Adjust channel real bits based on report descriptor */
42static void temperature_adjust_channel_bit_mask(struct iio_chan_spec *channels,
43					int channel, int size)
44{
45	channels[channel].scan_type.sign = 's';
46	/* Real storage bits will change based on the report desc. */
47	channels[channel].scan_type.realbits = size * 8;
48	/* Maximum size of a sample to capture is s32 */
49	channels[channel].scan_type.storagebits = sizeof(s32) * 8;
50}
51
52static int temperature_read_raw(struct iio_dev *indio_dev,
53				struct iio_chan_spec const *chan,
54				int *val, int *val2, long mask)
55{
56	struct temperature_state *temp_st = iio_priv(indio_dev);
57
58	switch (mask) {
59	case IIO_CHAN_INFO_RAW:
60		if (chan->type != IIO_TEMP)
61			return -EINVAL;
62		hid_sensor_power_state(
63			&temp_st->common_attributes, true);
64		*val = sensor_hub_input_attr_get_raw_value(
65			temp_st->common_attributes.hsdev,
66			HID_USAGE_SENSOR_TEMPERATURE,
67			HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
68			temp_st->temperature_attr.report_id,
69			SENSOR_HUB_SYNC,
70			temp_st->temperature_attr.logical_minimum < 0);
71		hid_sensor_power_state(
72				&temp_st->common_attributes,
73				false);
74
75		return IIO_VAL_INT;
76
77	case IIO_CHAN_INFO_SCALE:
78		*val = temp_st->scale_pre_decml;
79		*val2 = temp_st->scale_post_decml;
80		return temp_st->scale_precision;
81
82	case IIO_CHAN_INFO_OFFSET:
83		*val = temp_st->value_offset;
84		return IIO_VAL_INT;
85
86	case IIO_CHAN_INFO_SAMP_FREQ:
87		return hid_sensor_read_samp_freq_value(
88				&temp_st->common_attributes, val, val2);
89
90	case IIO_CHAN_INFO_HYSTERESIS:
91		return hid_sensor_read_raw_hyst_value(
92				&temp_st->common_attributes, val, val2);
93	default:
94		return -EINVAL;
95	}
96}
97
98static int temperature_write_raw(struct iio_dev *indio_dev,
99				struct iio_chan_spec const *chan,
100				int val, int val2, long mask)
101{
102	struct temperature_state *temp_st = iio_priv(indio_dev);
103
104	switch (mask) {
105	case IIO_CHAN_INFO_SAMP_FREQ:
106		return hid_sensor_write_samp_freq_value(
107				&temp_st->common_attributes, val, val2);
108	case IIO_CHAN_INFO_HYSTERESIS:
109		return hid_sensor_write_raw_hyst_value(
110				&temp_st->common_attributes, val, val2);
111	default:
112		return -EINVAL;
113	}
114}
115
116static const struct iio_info temperature_info = {
117	.read_raw = &temperature_read_raw,
118	.write_raw = &temperature_write_raw,
119};
120
121/* Callback handler to send event after all samples are received and captured */
122static int temperature_proc_event(struct hid_sensor_hub_device *hsdev,
123				unsigned int usage_id, void *pdev)
124{
125	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
126	struct temperature_state *temp_st = iio_priv(indio_dev);
127
128	if (atomic_read(&temp_st->common_attributes.data_ready))
129		iio_push_to_buffers_with_timestamp(indio_dev, &temp_st->scan,
130						   iio_get_time_ns(indio_dev));
131
132	return 0;
133}
134
135/* Capture samples in local storage */
136static int temperature_capture_sample(struct hid_sensor_hub_device *hsdev,
137				unsigned int usage_id, size_t raw_len,
138				char *raw_data, void *pdev)
139{
140	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
141	struct temperature_state *temp_st = iio_priv(indio_dev);
142
143	switch (usage_id) {
144	case HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE:
145		temp_st->scan.temperature_data = *(s32 *)raw_data;
146		return 0;
147	default:
148		return -EINVAL;
149	}
150}
151
152/* Parse report which is specific to an usage id*/
153static int temperature_parse_report(struct platform_device *pdev,
154				struct hid_sensor_hub_device *hsdev,
155				struct iio_chan_spec *channels,
156				unsigned int usage_id,
157				struct temperature_state *st)
158{
159	int ret;
160
161	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
162			usage_id,
163			HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
164			&st->temperature_attr);
165	if (ret < 0)
166		return ret;
167
168	temperature_adjust_channel_bit_mask(channels, 0,
169					st->temperature_attr.size);
170
171	st->scale_precision = hid_sensor_format_scale(
172				HID_USAGE_SENSOR_TEMPERATURE,
173				&st->temperature_attr,
174				&st->scale_pre_decml, &st->scale_post_decml);
175
176	/* Set Sensitivity field ids, when there is no individual modifier */
177	if (st->common_attributes.sensitivity.index < 0)
178		sensor_hub_input_get_attribute_info(hsdev,
179			HID_FEATURE_REPORT, usage_id,
180			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
181			HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
182			&st->common_attributes.sensitivity);
183
184	return ret;
185}
186
187static struct hid_sensor_hub_callbacks temperature_callbacks = {
188	.send_event = &temperature_proc_event,
189	.capture_sample = &temperature_capture_sample,
190};
191
192/* Function to initialize the processing for usage id */
193static int hid_temperature_probe(struct platform_device *pdev)
194{
195	static const char *name = "temperature";
196	struct iio_dev *indio_dev;
197	struct temperature_state *temp_st;
198	struct iio_chan_spec *temp_chans;
199	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
200	int ret;
201
202	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*temp_st));
203	if (!indio_dev)
204		return -ENOMEM;
205
206	temp_st = iio_priv(indio_dev);
207	temp_st->common_attributes.hsdev = hsdev;
208	temp_st->common_attributes.pdev = pdev;
209
210	ret = hid_sensor_parse_common_attributes(hsdev,
211					HID_USAGE_SENSOR_TEMPERATURE,
212					&temp_st->common_attributes);
213	if (ret)
214		return ret;
215
216	temp_chans = devm_kmemdup(&indio_dev->dev, temperature_channels,
217				sizeof(temperature_channels), GFP_KERNEL);
218	if (!temp_chans)
219		return -ENOMEM;
220
221	ret = temperature_parse_report(pdev, hsdev, temp_chans,
222				HID_USAGE_SENSOR_TEMPERATURE, temp_st);
223	if (ret)
224		return ret;
225
226	indio_dev->channels = temp_chans;
227	indio_dev->num_channels = ARRAY_SIZE(temperature_channels);
228	indio_dev->info = &temperature_info;
229	indio_dev->name = name;
230	indio_dev->modes = INDIO_DIRECT_MODE;
231
232	atomic_set(&temp_st->common_attributes.data_ready, 0);
233
234	ret = hid_sensor_setup_trigger(indio_dev, name,
235				&temp_st->common_attributes);
236	if (ret)
237		return ret;
238
239	platform_set_drvdata(pdev, indio_dev);
240
241	temperature_callbacks.pdev = pdev;
242	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE,
243					&temperature_callbacks);
244	if (ret)
245		goto error_remove_trigger;
246
247	ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
248	if (ret)
249		goto error_remove_callback;
250
251	return ret;
252
253error_remove_callback:
254	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
255error_remove_trigger:
256	hid_sensor_remove_trigger(indio_dev, &temp_st->common_attributes);
257	return ret;
258}
259
260/* Function to deinitialize the processing for usage id */
261static int hid_temperature_remove(struct platform_device *pdev)
262{
263	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
264	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
265	struct temperature_state *temp_st = iio_priv(indio_dev);
266
267	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
268	hid_sensor_remove_trigger(indio_dev, &temp_st->common_attributes);
269
270	return 0;
271}
272
273static const struct platform_device_id hid_temperature_ids[] = {
274	{
275		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
276		.name = "HID-SENSOR-200033",
277	},
278	{ /* sentinel */ }
279};
280MODULE_DEVICE_TABLE(platform, hid_temperature_ids);
281
282static struct platform_driver hid_temperature_platform_driver = {
283	.id_table = hid_temperature_ids,
284	.driver = {
285		.name	= "temperature-sensor",
286		.pm	= &hid_sensor_pm_ops,
287	},
288	.probe		= hid_temperature_probe,
289	.remove		= hid_temperature_remove,
290};
291module_platform_driver(hid_temperature_platform_driver);
292
293MODULE_DESCRIPTION("HID Environmental temperature sensor");
294MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
295MODULE_LICENSE("GPL v2");
296