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1 | ================================= |
2 | Intel Integrated Sensor Hub (ISH) | |
3 | ================================= | |
4 | ||
5 | A sensor hub enables the ability to offload sensor polling and algorithm | |
6 | processing to a dedicated low power co-processor. This allows the core | |
7 | processor to go into low power modes more often, resulting in the increased | |
8 | battery life. | |
9 | ||
10 | There are many vendors providing external sensor hubs confirming to HID | |
11 | Sensor usage tables, and used in several tablets, 2 in 1 convertible laptops | |
12 | and embedded products. Linux had this support since Linux 3.9. | |
13 | ||
14 | Intel® introduced integrated sensor hubs as a part of the SoC starting from | |
15 | Cherry Trail and now supported on multiple generations of CPU packages. There | |
16 | are many commercial devices already shipped with Integrated Sensor Hubs (ISH). | |
17 | These ISH also comply to HID sensor specification, but the difference is the | |
18 | transport protocol used for communication. The current external sensor hubs | |
19 | mainly use HID over i2C or USB. But ISH doesn't use either i2c or USB. | |
20 | ||
21 | 1. Overview | |
22 | =========== | |
23 | ||
24 | Using a analogy with a usbhid implementation, the ISH follows a similar model | |
25 | for a very high speed communication:: | |
26 | ||
27 | ----------------- ---------------------- | |
28 | | USB HID | --> | ISH HID | | |
29 | ----------------- ---------------------- | |
30 | ----------------- ---------------------- | |
31 | | USB protocol | --> | ISH Transport | | |
32 | ----------------- ---------------------- | |
33 | ----------------- ---------------------- | |
34 | | EHCI/XHCI | --> | ISH IPC | | |
35 | ----------------- ---------------------- | |
36 | PCI PCI | |
37 | ----------------- ---------------------- | |
38 | |Host controller| --> | ISH processor | | |
39 | ----------------- ---------------------- | |
40 | USB Link | |
41 | ----------------- ---------------------- | |
42 | | USB End points| --> | ISH Clients | | |
43 | ----------------- ---------------------- | |
44 | ||
45 | Like USB protocol provides a method for device enumeration, link management | |
46 | and user data encapsulation, the ISH also provides similar services. But it is | |
47 | very light weight tailored to manage and communicate with ISH client | |
48 | applications implemented in the firmware. | |
49 | ||
50 | The ISH allows multiple sensor management applications executing in the | |
51 | firmware. Like USB endpoints the messaging can be to/from a client. As part of | |
52 | enumeration process, these clients are identified. These clients can be simple | |
53 | HID sensor applications, sensor calibration application or senor firmware | |
54 | update application. | |
55 | ||
56 | The implementation model is similar, like USB bus, ISH transport is also | |
57 | implemented as a bus. Each client application executing in the ISH processor | |
58 | is registered as a device on this bus. The driver, which binds each device | |
59 | (ISH HID driver) identifies the device type and registers with the hid core. | |
60 | ||
61 | 2. ISH Implementation: Block Diagram | |
62 | ==================================== | |
63 | ||
64 | :: | |
65 | ||
66 | --------------------------- | |
67 | | User Space Applications | | |
68 | --------------------------- | |
69 | ||
70 | ----------------IIO ABI---------------- | |
71 | -------------------------- | |
72 | | IIO Sensor Drivers | | |
73 | -------------------------- | |
74 | -------------------------- | |
75 | | IIO core | | |
76 | -------------------------- | |
77 | -------------------------- | |
78 | | HID Sensor Hub MFD | | |
79 | -------------------------- | |
80 | -------------------------- | |
81 | | HID Core | | |
82 | -------------------------- | |
83 | -------------------------- | |
84 | | HID over ISH Client | | |
85 | -------------------------- | |
86 | -------------------------- | |
87 | | ISH Transport (ISHTP) | | |
88 | -------------------------- | |
89 | -------------------------- | |
90 | | IPC Drivers | | |
91 | -------------------------- | |
92 | OS | |
93 | ---------------- PCI ----------------- | |
94 | Hardware + Firmware | |
95 | ---------------------------- | |
96 | | ISH Hardware/Firmware(FW) | | |
97 | ---------------------------- | |
98 | ||
99 | 3. High level processing in above blocks | |
100 | ======================================== | |
101 | ||
102 | 3.1 Hardware Interface | |
103 | ---------------------- | |
104 | ||
105 | The ISH is exposed as "Non-VGA unclassified PCI device" to the host. The PCI | |
106 | product and vendor IDs are changed from different generations of processors. So | |
107 | the source code which enumerate drivers needs to update from generation to | |
108 | generation. | |
109 | ||
110 | 3.2 Inter Processor Communication (IPC) driver | |
111 | ---------------------------------------------- | |
112 | ||
113 | Location: drivers/hid/intel-ish-hid/ipc | |
114 | ||
115 | The IPC message used memory mapped I/O. The registers are defined in | |
116 | hw-ish-regs.h. | |
117 | ||
118 | 3.2.1 IPC/FW message types | |
119 | ^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
120 | ||
121 | There are two types of messages, one for management of link and other messages | |
122 | are to and from transport layers. | |
123 | ||
124 | TX and RX of Transport messages | |
125 | ............................... | |
126 | ||
127 | A set of memory mapped register offers support of multi byte messages TX and | |
128 | RX (E.g.IPC_REG_ISH2HOST_MSG, IPC_REG_HOST2ISH_MSG). The IPC layer maintains | |
129 | internal queues to sequence messages and send them in order to the FW. | |
130 | Optionally the caller can register handler to get notification of completion. | |
131 | A door bell mechanism is used in messaging to trigger processing in host and | |
132 | client firmware side. When ISH interrupt handler is called, the ISH2HOST | |
133 | doorbell register is used by host drivers to determine that the interrupt | |
134 | is for ISH. | |
135 | ||
136 | Each side has 32 32-bit message registers and a 32-bit doorbell. Doorbell | |
137 | register has the following format: | |
138 | Bits 0..6: fragment length (7 bits are used) | |
139 | Bits 10..13: encapsulated protocol | |
140 | Bits 16..19: management command (for IPC management protocol) | |
141 | Bit 31: doorbell trigger (signal H/W interrupt to the other side) | |
142 | Other bits are reserved, should be 0. | |
143 | ||
144 | 3.2.2 Transport layer interface | |
145 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
146 | ||
147 | To abstract HW level IPC communication, a set of callbacks are registered. | |
148 | The transport layer uses them to send and receive messages. | |
149 | Refer to struct ishtp_hw_ops for callbacks. | |
150 | ||
151 | 3.3 ISH Transport layer | |
152 | ----------------------- | |
153 | ||
154 | Location: drivers/hid/intel-ish-hid/ishtp/ | |
155 | ||
156 | 3.3.1 A Generic Transport Layer | |
157 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
158 | ||
159 | The transport layer is a bi-directional protocol, which defines: | |
160 | - Set of commands to start, stop, connect, disconnect and flow control | |
161 | (ishtp/hbm.h) for details | |
162 | - A flow control mechanism to avoid buffer overflows | |
163 | ||
164 | This protocol resembles bus messages described in the following document: | |
165 | http://www.intel.com/content/dam/www/public/us/en/documents/technical-\ | |
166 | specifications/dcmi-hi-1-0-spec.pdf "Chapter 7: Bus Message Layer" | |
167 | ||
168 | 3.3.2 Connection and Flow Control Mechanism | |
169 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
170 | ||
171 | Each FW client and a protocol is identified by an UUID. In order to communicate | |
172 | to a FW client, a connection must be established using connect request and | |
173 | response bus messages. If successful, a pair (host_client_id and fw_client_id) | |
174 | will identify the connection. | |
175 | ||
176 | Once connection is established, peers send each other flow control bus messages | |
177 | independently. Every peer may send a message only if it has received a | |
178 | flow-control credit before. Once it sent a message, it may not send another one | |
179 | before receiving the next flow control credit. | |
180 | Either side can send disconnect request bus message to end communication. Also | |
181 | the link will be dropped if major FW reset occurs. | |
182 | ||
183 | 3.3.3 Peer to Peer data transfer | |
184 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | |
185 | ||
186 | Peer to Peer data transfer can happen with or without using DMA. Depending on | |
187 | the sensor bandwidth requirement DMA can be enabled by using module parameter | |
188 | ishtp_use_dma under intel_ishtp. | |
189 | ||
190 | Each side (host and FW) manages its DMA transfer memory independently. When an | |
191 | ISHTP client from either host or FW side wants to send something, it decides | |
192 | whether to send over IPC or over DMA; for each transfer the decision is | |
193 | independent. The sending side sends DMA_XFER message when the message is in | |
194 | the respective host buffer (TX when host client sends, RX when FW client | |
195 | sends). The recipient of DMA message responds with DMA_XFER_ACK, indicating | |
196 | the sender that the memory region for that message may be reused. | |
197 | ||
198 | DMA initialization is started with host sending DMA_ALLOC_NOTIFY bus message | |
199 | (that includes RX buffer) and FW responds with DMA_ALLOC_NOTIFY_ACK. | |
200 | Additionally to DMA address communication, this sequence checks capabilities: | |
201 | if thw host doesn't support DMA, then it won't send DMA allocation, so FW can't | |
202 | send DMA; if FW doesn't support DMA then it won't respond with | |
203 | DMA_ALLOC_NOTIFY_ACK, in which case host will not use DMA transfers. | |
204 | Here ISH acts as busmaster DMA controller. Hence when host sends DMA_XFER, | |
205 | it's request to do host->ISH DMA transfer; when FW sends DMA_XFER, it means | |
206 | that it already did DMA and the message resides at host. Thus, DMA_XFER | |
207 | and DMA_XFER_ACK act as ownership indicators. | |
208 | ||
209 | At initial state all outgoing memory belongs to the sender (TX to host, RX to | |
210 | FW), DMA_XFER transfers ownership on the region that contains ISHTP message to | |
211 | the receiving side, DMA_XFER_ACK returns ownership to the sender. A sender | |
212 | needs not wait for previous DMA_XFER to be ack'ed, and may send another message | |
213 | as long as remaining continuous memory in its ownership is enough. | |
214 | In principle, multiple DMA_XFER and DMA_XFER_ACK messages may be sent at once | |
215 | (up to IPC MTU), thus allowing for interrupt throttling. | |
216 | Currently, ISH FW decides to send over DMA if ISHTP message is more than 3 IPC | |
217 | fragments and via IPC otherwise. | |
218 | ||
219 | 3.3.4 Ring Buffers | |
220 | ^^^^^^^^^^^^^^^^^^ | |
221 | ||
222 | When a client initiate a connection, a ring or RX and TX buffers are allocated. | |
223 | The size of ring can be specified by the client. HID client set 16 and 32 for | |
224 | TX and RX buffers respectively. On send request from client, the data to be | |
225 | sent is copied to one of the send ring buffer and scheduled to be sent using | |
226 | bus message protocol. These buffers are required because the FW may have not | |
227 | have processed the last message and may not have enough flow control credits | |
228 | to send. Same thing holds true on receive side and flow control is required. | |
229 | ||
230 | 3.3.5 Host Enumeration | |
231 | ^^^^^^^^^^^^^^^^^^^^^^ | |
232 | ||
233 | The host enumeration bus command allow discovery of clients present in the FW. | |
234 | There can be multiple sensor clients and clients for calibration function. | |
235 | ||
236 | To ease in implantation and allow independent driver handle each client | |
237 | this transport layer takes advantage of Linux Bus driver model. Each | |
e94f32c1 | 238 | client is registered as device on the transport bus (ishtp bus). |
cca47861 MCC |
239 | |
240 | Enumeration sequence of messages: | |
241 | ||
242 | - Host sends HOST_START_REQ_CMD, indicating that host ISHTP layer is up. | |
243 | - FW responds with HOST_START_RES_CMD | |
244 | - Host sends HOST_ENUM_REQ_CMD (enumerate FW clients) | |
245 | - FW responds with HOST_ENUM_RES_CMD that includes bitmap of available FW | |
246 | client IDs | |
247 | - For each FW ID found in that bitmap host sends | |
248 | HOST_CLIENT_PROPERTIES_REQ_CMD | |
249 | - FW responds with HOST_CLIENT_PROPERTIES_RES_CMD. Properties include UUID, | |
250 | max ISHTP message size, etc. | |
251 | - Once host received properties for that last discovered client, it considers | |
252 | ISHTP device fully functional (and allocates DMA buffers) | |
253 | ||
254 | 3.4 HID over ISH Client | |
255 | ----------------------- | |
256 | ||
257 | Location: drivers/hid/intel-ish-hid | |
258 | ||
259 | The ISHTP client driver is responsible for: | |
260 | ||
261 | - enumerate HID devices under FW ISH client | |
262 | - Get Report descriptor | |
263 | - Register with HID core as a LL driver | |
264 | - Process Get/Set feature request | |
265 | - Get input reports | |
266 | ||
267 | 3.5 HID Sensor Hub MFD and IIO sensor drivers | |
268 | --------------------------------------------- | |
269 | ||
270 | The functionality in these drivers is the same as an external sensor hub. | |
271 | Refer to | |
272 | Documentation/hid/hid-sensor.rst for HID sensor | |
273 | Documentation/ABI/testing/sysfs-bus-iio for IIO ABIs to user space | |
274 | ||
275 | 3.6 End to End HID transport Sequence Diagram | |
276 | --------------------------------------------- | |
277 | ||
278 | :: | |
279 | ||
280 | HID-ISH-CLN ISHTP IPC HW | |
281 | | | | | | |
282 | | | |-----WAKE UP------------------>| | |
283 | | | | | | |
284 | | | |-----HOST READY--------------->| | |
285 | | | | | | |
286 | | | |<----MNG_RESET_NOTIFY_ACK----- | | |
287 | | | | | | |
288 | | |<----ISHTP_START------ | | | |
289 | | | | | | |
290 | | |<-----------------HOST_START_RES_CMD-------------------| | |
291 | | | | | | |
292 | | |------------------QUERY_SUBSCRIBER-------------------->| | |
293 | | | | | | |
294 | | |------------------HOST_ENUM_REQ_CMD------------------->| | |
295 | | | | | | |
296 | | |<-----------------HOST_ENUM_RES_CMD--------------------| | |
297 | | | | | | |
298 | | |------------------HOST_CLIENT_PROPERTIES_REQ_CMD------>| | |
299 | | | | | | |
300 | | |<-----------------HOST_CLIENT_PROPERTIES_RES_CMD-------| | |
301 | | Create new device on in ishtp bus | | | |
302 | | | | | | |
303 | | |------------------HOST_CLIENT_PROPERTIES_REQ_CMD------>| | |
304 | | | | | | |
305 | | |<-----------------HOST_CLIENT_PROPERTIES_RES_CMD-------| | |
306 | | Create new device on in ishtp bus | | | |
307 | | | | | | |
308 | | |--Repeat HOST_CLIENT_PROPERTIES_REQ_CMD-till last one--| | |
309 | | | | | | |
310 | probed() | |
311 | |----ishtp_cl_connect--->|----------------- CLIENT_CONNECT_REQ_CMD-------------->| | |
312 | | | | | | |
313 | | |<----------------CLIENT_CONNECT_RES_CMD----------------| | |
314 | | | | | | |
315 | |register event callback | | | | |
316 | | | | | | |
317 | |ishtp_cl_send( | |
318 | HOSTIF_DM_ENUM_DEVICES) |----------fill ishtp_msg_hdr struct write to HW----- >| | |
319 | | | | | | |
320 | | | |<-----IRQ(IPC_PROTOCOL_ISHTP---| | |
321 | | | | | | |
322 | |<--ENUM_DEVICE RSP------| | | | |
323 | | | | | | |
324 | for each enumerated device | |
325 | |ishtp_cl_send( | |
326 | HOSTIF_GET_HID_DESCRIPTOR|----------fill ishtp_msg_hdr struct write to HW----- >| | |
327 | | | | | | |
328 | ...Response | |
329 | | | | | | |
330 | for each enumerated device | |
331 | |ishtp_cl_send( | |
332 | HOSTIF_GET_REPORT_DESCRIPTOR|--------------fill ishtp_msg_hdr struct write to HW-- >| | |
333 | | | | | | |
334 | | | | | | |
335 | hid_allocate_device | |
336 | | | | | | |
337 | hid_add_device | | | | |
338 | | | | | | |
339 | ||
340 | ||
341 | 3.7 ISH Debugging | |
342 | ----------------- | |
343 | ||
344 | To debug ISH, event tracing mechanism is used. To enable debug logs | |
345 | echo 1 > /sys/kernel/debug/tracing/events/intel_ish/enable | |
346 | cat sys/kernel/debug/tracing/trace | |
347 | ||
348 | 3.8 ISH IIO sysfs Example on Lenovo thinkpad Yoga 260 | |
349 | ----------------------------------------------------- | |
350 | ||
351 | :: | |
352 | ||
353 | root@otcpl-ThinkPad-Yoga-260:~# tree -l /sys/bus/iio/devices/ | |
354 | /sys/bus/iio/devices/ | |
355 | ├── iio:device0 -> ../../../devices/0044:8086:22D8.0001/HID-SENSOR-200073.9.auto/iio:device0 | |
356 | │ ├── buffer | |
357 | │ │ ├── enable | |
358 | │ │ ├── length | |
359 | │ │ └── watermark | |
360 | ... | |
361 | │ ├── in_accel_hysteresis | |
362 | │ ├── in_accel_offset | |
363 | │ ├── in_accel_sampling_frequency | |
364 | │ ├── in_accel_scale | |
365 | │ ├── in_accel_x_raw | |
366 | │ ├── in_accel_y_raw | |
367 | │ ├── in_accel_z_raw | |
368 | │ ├── name | |
369 | │ ├── scan_elements | |
370 | │ │ ├── in_accel_x_en | |
371 | │ │ ├── in_accel_x_index | |
372 | │ │ ├── in_accel_x_type | |
373 | │ │ ├── in_accel_y_en | |
374 | │ │ ├── in_accel_y_index | |
375 | │ │ ├── in_accel_y_type | |
376 | │ │ ├── in_accel_z_en | |
377 | │ │ ├── in_accel_z_index | |
378 | │ │ └── in_accel_z_type | |
379 | ... | |
380 | │ │ ├── devices | |
381 | │ │ │ │ ├── buffer | |
382 | │ │ │ │ │ ├── enable | |
383 | │ │ │ │ │ ├── length | |
384 | │ │ │ │ │ └── watermark | |
385 | │ │ │ │ ├── dev | |
386 | │ │ │ │ ├── in_intensity_both_raw | |
387 | │ │ │ │ ├── in_intensity_hysteresis | |
388 | │ │ │ │ ├── in_intensity_offset | |
389 | │ │ │ │ ├── in_intensity_sampling_frequency | |
390 | │ │ │ │ ├── in_intensity_scale | |
391 | │ │ │ │ ├── name | |
392 | │ │ │ │ ├── scan_elements | |
393 | │ │ │ │ │ ├── in_intensity_both_en | |
394 | │ │ │ │ │ ├── in_intensity_both_index | |
395 | │ │ │ │ │ └── in_intensity_both_type | |
396 | │ │ │ │ ├── trigger | |
397 | │ │ │ │ │ └── current_trigger | |
398 | ... | |
399 | │ │ │ │ ├── buffer | |
400 | │ │ │ │ │ ├── enable | |
401 | │ │ │ │ │ ├── length | |
402 | │ │ │ │ │ └── watermark | |
403 | │ │ │ │ ├── dev | |
404 | │ │ │ │ ├── in_magn_hysteresis | |
405 | │ │ │ │ ├── in_magn_offset | |
406 | │ │ │ │ ├── in_magn_sampling_frequency | |
407 | │ │ │ │ ├── in_magn_scale | |
408 | │ │ │ │ ├── in_magn_x_raw | |
409 | │ │ │ │ ├── in_magn_y_raw | |
410 | │ │ │ │ ├── in_magn_z_raw | |
411 | │ │ │ │ ├── in_rot_from_north_magnetic_tilt_comp_raw | |
412 | │ │ │ │ ├── in_rot_hysteresis | |
413 | │ │ │ │ ├── in_rot_offset | |
414 | │ │ │ │ ├── in_rot_sampling_frequency | |
415 | │ │ │ │ ├── in_rot_scale | |
416 | │ │ │ │ ├── name | |
417 | ... | |
418 | │ │ │ │ ├── scan_elements | |
419 | │ │ │ │ │ ├── in_magn_x_en | |
420 | │ │ │ │ │ ├── in_magn_x_index | |
421 | │ │ │ │ │ ├── in_magn_x_type | |
422 | │ │ │ │ │ ├── in_magn_y_en | |
423 | │ │ │ │ │ ├── in_magn_y_index | |
424 | │ │ │ │ │ ├── in_magn_y_type | |
425 | │ │ │ │ │ ├── in_magn_z_en | |
426 | │ │ │ │ │ ├── in_magn_z_index | |
427 | │ │ │ │ │ ├── in_magn_z_type | |
428 | │ │ │ │ │ ├── in_rot_from_north_magnetic_tilt_comp_en | |
429 | │ │ │ │ │ ├── in_rot_from_north_magnetic_tilt_comp_index | |
430 | │ │ │ │ │ └── in_rot_from_north_magnetic_tilt_comp_type | |
431 | │ │ │ │ ├── trigger | |
432 | │ │ │ │ │ └── current_trigger | |
433 | ... | |
434 | │ │ │ │ ├── buffer | |
435 | │ │ │ │ │ ├── enable | |
436 | │ │ │ │ │ ├── length | |
437 | │ │ │ │ │ └── watermark | |
438 | │ │ │ │ ├── dev | |
439 | │ │ │ │ ├── in_anglvel_hysteresis | |
440 | │ │ │ │ ├── in_anglvel_offset | |
441 | │ │ │ │ ├── in_anglvel_sampling_frequency | |
442 | │ │ │ │ ├── in_anglvel_scale | |
443 | │ │ │ │ ├── in_anglvel_x_raw | |
444 | │ │ │ │ ├── in_anglvel_y_raw | |
445 | │ │ │ │ ├── in_anglvel_z_raw | |
446 | │ │ │ │ ├── name | |
447 | │ │ │ │ ├── scan_elements | |
448 | │ │ │ │ │ ├── in_anglvel_x_en | |
449 | │ │ │ │ │ ├── in_anglvel_x_index | |
450 | │ │ │ │ │ ├── in_anglvel_x_type | |
451 | │ │ │ │ │ ├── in_anglvel_y_en | |
452 | │ │ │ │ │ ├── in_anglvel_y_index | |
453 | │ │ │ │ │ ├── in_anglvel_y_type | |
454 | │ │ │ │ │ ├── in_anglvel_z_en | |
455 | │ │ │ │ │ ├── in_anglvel_z_index | |
456 | │ │ │ │ │ └── in_anglvel_z_type | |
457 | │ │ │ │ ├── trigger | |
458 | │ │ │ │ │ └── current_trigger | |
459 | ... | |
460 | │ │ │ │ ├── buffer | |
461 | │ │ │ │ │ ├── enable | |
462 | │ │ │ │ │ ├── length | |
463 | │ │ │ │ │ └── watermark | |
464 | │ │ │ │ ├── dev | |
465 | │ │ │ │ ├── in_anglvel_hysteresis | |
466 | │ │ │ │ ├── in_anglvel_offset | |
467 | │ │ │ │ ├── in_anglvel_sampling_frequency | |
468 | │ │ │ │ ├── in_anglvel_scale | |
469 | │ │ │ │ ├── in_anglvel_x_raw | |
470 | │ │ │ │ ├── in_anglvel_y_raw | |
471 | │ │ │ │ ├── in_anglvel_z_raw | |
472 | │ │ │ │ ├── name | |
473 | │ │ │ │ ├── scan_elements | |
474 | │ │ │ │ │ ├── in_anglvel_x_en | |
475 | │ │ │ │ │ ├── in_anglvel_x_index | |
476 | │ │ │ │ │ ├── in_anglvel_x_type | |
477 | │ │ │ │ │ ├── in_anglvel_y_en | |
478 | │ │ │ │ │ ├── in_anglvel_y_index | |
479 | │ │ │ │ │ ├── in_anglvel_y_type | |
480 | │ │ │ │ │ ├── in_anglvel_z_en | |
481 | │ │ │ │ │ ├── in_anglvel_z_index | |
482 | │ │ │ │ │ └── in_anglvel_z_type | |
483 | │ │ │ │ ├── trigger | |
484 | │ │ │ │ │ └── current_trigger | |
485 | ... |