• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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/iio/triggered_buffer.h>
11 #include <linux/iio/trigger_consumer.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 
15 #include "../common/hid-sensors/hid-sensor-trigger.h"
16 
17 struct temperature_state {
18 	struct hid_sensor_common common_attributes;
19 	struct hid_sensor_hub_attribute_info temperature_attr;
20 	struct {
21 		s32 temperature_data;
22 		u64 timestamp __aligned(8);
23 	} scan;
24 	int scale_pre_decml;
25 	int scale_post_decml;
26 	int scale_precision;
27 	int value_offset;
28 };
29 
30 /* Channel definitions */
31 static const struct iio_chan_spec temperature_channels[] = {
32 	{
33 		.type = IIO_TEMP,
34 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
35 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
36 			BIT(IIO_CHAN_INFO_SCALE) |
37 			BIT(IIO_CHAN_INFO_SAMP_FREQ) |
38 			BIT(IIO_CHAN_INFO_HYSTERESIS),
39 	},
40 	IIO_CHAN_SOFT_TIMESTAMP(1),
41 };
42 
43 /* Adjust channel real bits based on report descriptor */
temperature_adjust_channel_bit_mask(struct iio_chan_spec * channels,int channel,int size)44 static void temperature_adjust_channel_bit_mask(struct iio_chan_spec *channels,
45 					int channel, int size)
46 {
47 	channels[channel].scan_type.sign = 's';
48 	/* Real storage bits will change based on the report desc. */
49 	channels[channel].scan_type.realbits = size * 8;
50 	/* Maximum size of a sample to capture is s32 */
51 	channels[channel].scan_type.storagebits = sizeof(s32) * 8;
52 }
53 
temperature_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)54 static int temperature_read_raw(struct iio_dev *indio_dev,
55 				struct iio_chan_spec const *chan,
56 				int *val, int *val2, long mask)
57 {
58 	struct temperature_state *temp_st = iio_priv(indio_dev);
59 
60 	switch (mask) {
61 	case IIO_CHAN_INFO_RAW:
62 		if (chan->type != IIO_TEMP)
63 			return -EINVAL;
64 		hid_sensor_power_state(
65 			&temp_st->common_attributes, true);
66 		*val = sensor_hub_input_attr_get_raw_value(
67 			temp_st->common_attributes.hsdev,
68 			HID_USAGE_SENSOR_TEMPERATURE,
69 			HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
70 			temp_st->temperature_attr.report_id,
71 			SENSOR_HUB_SYNC,
72 			temp_st->temperature_attr.logical_minimum < 0);
73 		hid_sensor_power_state(
74 				&temp_st->common_attributes,
75 				false);
76 
77 		return IIO_VAL_INT;
78 
79 	case IIO_CHAN_INFO_SCALE:
80 		*val = temp_st->scale_pre_decml;
81 		*val2 = temp_st->scale_post_decml;
82 		return temp_st->scale_precision;
83 
84 	case IIO_CHAN_INFO_OFFSET:
85 		*val = temp_st->value_offset;
86 		return IIO_VAL_INT;
87 
88 	case IIO_CHAN_INFO_SAMP_FREQ:
89 		return hid_sensor_read_samp_freq_value(
90 				&temp_st->common_attributes, val, val2);
91 
92 	case IIO_CHAN_INFO_HYSTERESIS:
93 		return hid_sensor_read_raw_hyst_value(
94 				&temp_st->common_attributes, val, val2);
95 	default:
96 		return -EINVAL;
97 	}
98 }
99 
temperature_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)100 static int temperature_write_raw(struct iio_dev *indio_dev,
101 				struct iio_chan_spec const *chan,
102 				int val, int val2, long mask)
103 {
104 	struct temperature_state *temp_st = iio_priv(indio_dev);
105 
106 	switch (mask) {
107 	case IIO_CHAN_INFO_SAMP_FREQ:
108 		return hid_sensor_write_samp_freq_value(
109 				&temp_st->common_attributes, val, val2);
110 	case IIO_CHAN_INFO_HYSTERESIS:
111 		return hid_sensor_write_raw_hyst_value(
112 				&temp_st->common_attributes, val, val2);
113 	default:
114 		return -EINVAL;
115 	}
116 }
117 
118 static const struct iio_info temperature_info = {
119 	.read_raw = &temperature_read_raw,
120 	.write_raw = &temperature_write_raw,
121 };
122 
123 /* Callback handler to send event after all samples are received and captured */
temperature_proc_event(struct hid_sensor_hub_device * hsdev,unsigned int usage_id,void * pdev)124 static int temperature_proc_event(struct hid_sensor_hub_device *hsdev,
125 				unsigned int usage_id, void *pdev)
126 {
127 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
128 	struct temperature_state *temp_st = iio_priv(indio_dev);
129 
130 	if (atomic_read(&temp_st->common_attributes.data_ready))
131 		iio_push_to_buffers_with_timestamp(indio_dev, &temp_st->scan,
132 						   iio_get_time_ns(indio_dev));
133 
134 	return 0;
135 }
136 
137 /* Capture samples in local storage */
temperature_capture_sample(struct hid_sensor_hub_device * hsdev,unsigned int usage_id,size_t raw_len,char * raw_data,void * pdev)138 static int temperature_capture_sample(struct hid_sensor_hub_device *hsdev,
139 				unsigned int usage_id, size_t raw_len,
140 				char *raw_data, void *pdev)
141 {
142 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
143 	struct temperature_state *temp_st = iio_priv(indio_dev);
144 
145 	switch (usage_id) {
146 	case HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE:
147 		temp_st->scan.temperature_data = *(s32 *)raw_data;
148 		return 0;
149 	default:
150 		return -EINVAL;
151 	}
152 }
153 
154 /* Parse report which is specific to an usage id*/
temperature_parse_report(struct platform_device * pdev,struct hid_sensor_hub_device * hsdev,struct iio_chan_spec * channels,unsigned int usage_id,struct temperature_state * st)155 static int temperature_parse_report(struct platform_device *pdev,
156 				struct hid_sensor_hub_device *hsdev,
157 				struct iio_chan_spec *channels,
158 				unsigned int usage_id,
159 				struct temperature_state *st)
160 {
161 	int ret;
162 
163 	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
164 			usage_id,
165 			HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
166 			&st->temperature_attr);
167 	if (ret < 0)
168 		return ret;
169 
170 	temperature_adjust_channel_bit_mask(channels, 0,
171 					st->temperature_attr.size);
172 
173 	st->scale_precision = hid_sensor_format_scale(
174 				HID_USAGE_SENSOR_TEMPERATURE,
175 				&st->temperature_attr,
176 				&st->scale_pre_decml, &st->scale_post_decml);
177 
178 	/* Set Sensitivity field ids, when there is no individual modifier */
179 	if (st->common_attributes.sensitivity.index < 0)
180 		sensor_hub_input_get_attribute_info(hsdev,
181 			HID_FEATURE_REPORT, usage_id,
182 			HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
183 			HID_USAGE_SENSOR_DATA_ENVIRONMENTAL_TEMPERATURE,
184 			&st->common_attributes.sensitivity);
185 
186 	return ret;
187 }
188 
189 static struct hid_sensor_hub_callbacks temperature_callbacks = {
190 	.send_event = &temperature_proc_event,
191 	.capture_sample = &temperature_capture_sample,
192 };
193 
194 /* Function to initialize the processing for usage id */
hid_temperature_probe(struct platform_device * pdev)195 static int hid_temperature_probe(struct platform_device *pdev)
196 {
197 	static const char *name = "temperature";
198 	struct iio_dev *indio_dev;
199 	struct temperature_state *temp_st;
200 	struct iio_chan_spec *temp_chans;
201 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
202 	int ret;
203 
204 	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*temp_st));
205 	if (!indio_dev)
206 		return -ENOMEM;
207 
208 	temp_st = iio_priv(indio_dev);
209 	temp_st->common_attributes.hsdev = hsdev;
210 	temp_st->common_attributes.pdev = pdev;
211 
212 	ret = hid_sensor_parse_common_attributes(hsdev,
213 					HID_USAGE_SENSOR_TEMPERATURE,
214 					&temp_st->common_attributes);
215 	if (ret)
216 		return ret;
217 
218 	temp_chans = devm_kmemdup(&indio_dev->dev, temperature_channels,
219 				sizeof(temperature_channels), GFP_KERNEL);
220 	if (!temp_chans)
221 		return -ENOMEM;
222 
223 	ret = temperature_parse_report(pdev, hsdev, temp_chans,
224 				HID_USAGE_SENSOR_TEMPERATURE, temp_st);
225 	if (ret)
226 		return ret;
227 
228 	indio_dev->channels = temp_chans;
229 	indio_dev->num_channels = ARRAY_SIZE(temperature_channels);
230 	indio_dev->dev.parent = &pdev->dev;
231 	indio_dev->info = &temperature_info;
232 	indio_dev->name = name;
233 	indio_dev->modes = INDIO_DIRECT_MODE;
234 
235 	ret = devm_iio_triggered_buffer_setup(&pdev->dev, indio_dev,
236 					&iio_pollfunc_store_time, NULL, NULL);
237 	if (ret)
238 		return ret;
239 
240 	atomic_set(&temp_st->common_attributes.data_ready, 0);
241 	ret = hid_sensor_setup_trigger(indio_dev, name,
242 				&temp_st->common_attributes);
243 	if (ret)
244 		return ret;
245 
246 	platform_set_drvdata(pdev, indio_dev);
247 
248 	temperature_callbacks.pdev = pdev;
249 	ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE,
250 					&temperature_callbacks);
251 	if (ret)
252 		goto error_remove_trigger;
253 
254 	ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
255 	if (ret)
256 		goto error_remove_callback;
257 
258 	return ret;
259 
260 error_remove_callback:
261 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
262 error_remove_trigger:
263 	hid_sensor_remove_trigger(&temp_st->common_attributes);
264 	return ret;
265 }
266 
267 /* Function to deinitialize the processing for usage id */
hid_temperature_remove(struct platform_device * pdev)268 static int hid_temperature_remove(struct platform_device *pdev)
269 {
270 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
271 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
272 	struct temperature_state *temp_st = iio_priv(indio_dev);
273 
274 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
275 	hid_sensor_remove_trigger(&temp_st->common_attributes);
276 
277 	return 0;
278 }
279 
280 static const struct platform_device_id hid_temperature_ids[] = {
281 	{
282 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
283 		.name = "HID-SENSOR-200033",
284 	},
285 	{ /* sentinel */ }
286 };
287 MODULE_DEVICE_TABLE(platform, hid_temperature_ids);
288 
289 static struct platform_driver hid_temperature_platform_driver = {
290 	.id_table = hid_temperature_ids,
291 	.driver = {
292 		.name	= "temperature-sensor",
293 		.pm	= &hid_sensor_pm_ops,
294 	},
295 	.probe		= hid_temperature_probe,
296 	.remove		= hid_temperature_remove,
297 };
298 module_platform_driver(hid_temperature_platform_driver);
299 
300 MODULE_DESCRIPTION("HID Environmental temperature sensor");
301 MODULE_AUTHOR("Song Hongyan <hongyan.song@intel.com>");
302 MODULE_LICENSE("GPL v2");
303