1 // SPDX-License-Identifier: GPL-2.0
3 * HID class driver for the Greybus.
5 * Copyright 2014 Google Inc.
6 * Copyright 2014 Linaro Ltd.
9 #include <linux/bitops.h>
10 #include <linux/hid.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/slab.h>
18 /* Greybus HID device's structure */
20 struct gb_bundle *bundle;
21 struct gb_connection *connection;
23 struct hid_device *hid;
24 struct gb_hid_desc_response hdesc;
27 #define GB_HID_STARTED 0x01
28 #define GB_HID_READ_PENDING 0x04
34 /* Routines to get controller's information over greybus */
36 /* Operations performed on greybus */
37 static int gb_hid_get_desc(struct gb_hid *ghid)
39 return gb_operation_sync(ghid->connection, GB_HID_TYPE_GET_DESC, NULL,
40 0, &ghid->hdesc, sizeof(ghid->hdesc));
43 static int gb_hid_get_report_desc(struct gb_hid *ghid, char *rdesc)
47 ret = gb_pm_runtime_get_sync(ghid->bundle);
51 ret = gb_operation_sync(ghid->connection, GB_HID_TYPE_GET_REPORT_DESC,
53 le16_to_cpu(ghid->hdesc.wReportDescLength));
55 gb_pm_runtime_put_autosuspend(ghid->bundle);
60 static int gb_hid_set_power(struct gb_hid *ghid, int type)
64 ret = gb_pm_runtime_get_sync(ghid->bundle);
68 ret = gb_operation_sync(ghid->connection, type, NULL, 0, NULL, 0);
70 gb_pm_runtime_put_autosuspend(ghid->bundle);
75 static int gb_hid_get_report(struct gb_hid *ghid, u8 report_type, u8 report_id,
76 unsigned char *buf, int len)
78 struct gb_hid_get_report_request request;
81 ret = gb_pm_runtime_get_sync(ghid->bundle);
85 request.report_type = report_type;
86 request.report_id = report_id;
88 ret = gb_operation_sync(ghid->connection, GB_HID_TYPE_GET_REPORT,
89 &request, sizeof(request), buf, len);
91 gb_pm_runtime_put_autosuspend(ghid->bundle);
96 static int gb_hid_set_report(struct gb_hid *ghid, u8 report_type, u8 report_id,
97 unsigned char *buf, int len)
99 struct gb_hid_set_report_request *request;
100 struct gb_operation *operation;
101 int ret, size = sizeof(*request) + len - 1;
103 ret = gb_pm_runtime_get_sync(ghid->bundle);
107 operation = gb_operation_create(ghid->connection,
108 GB_HID_TYPE_SET_REPORT, size, 0,
111 gb_pm_runtime_put_autosuspend(ghid->bundle);
115 request = operation->request->payload;
116 request->report_type = report_type;
117 request->report_id = report_id;
118 memcpy(request->report, buf, len);
120 ret = gb_operation_request_send_sync(operation);
122 dev_err(&operation->connection->bundle->dev,
123 "failed to set report: %d\n", ret);
128 gb_operation_put(operation);
129 gb_pm_runtime_put_autosuspend(ghid->bundle);
134 static int gb_hid_request_handler(struct gb_operation *op)
136 struct gb_connection *connection = op->connection;
137 struct gb_hid *ghid = gb_connection_get_data(connection);
138 struct gb_hid_input_report_request *request = op->request->payload;
140 if (op->type != GB_HID_TYPE_IRQ_EVENT) {
141 dev_err(&connection->bundle->dev,
142 "unsupported unsolicited request\n");
146 if (test_bit(GB_HID_STARTED, &ghid->flags))
147 hid_input_report(ghid->hid, HID_INPUT_REPORT,
148 request->report, op->request->payload_size, 1);
153 static int gb_hid_report_len(struct hid_report *report)
155 return ((report->size - 1) >> 3) + 1 +
156 report->device->report_enum[report->type].numbered;
159 static void gb_hid_find_max_report(struct hid_device *hid, unsigned int type,
162 struct hid_report *report;
165 list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
166 size = gb_hid_report_len(report);
172 static void gb_hid_free_buffers(struct gb_hid *ghid)
179 static int gb_hid_alloc_buffers(struct gb_hid *ghid, size_t bufsize)
181 ghid->inbuf = kzalloc(bufsize, GFP_KERNEL);
185 ghid->bufsize = bufsize;
190 /* Routines dealing with reports */
191 static void gb_hid_init_report(struct gb_hid *ghid, struct hid_report *report)
195 size = gb_hid_report_len(report);
196 if (gb_hid_get_report(ghid, report->type, report->id, ghid->inbuf,
201 * hid->driver_lock is held as we are in probe function,
202 * we just need to setup the input fields, so using
203 * hid_report_raw_event is safe.
205 hid_report_raw_event(ghid->hid, report->type, ghid->inbuf, size, 1);
208 static void gb_hid_init_reports(struct gb_hid *ghid)
210 struct hid_device *hid = ghid->hid;
211 struct hid_report *report;
213 list_for_each_entry(report,
214 &hid->report_enum[HID_INPUT_REPORT].report_list,
216 gb_hid_init_report(ghid, report);
218 list_for_each_entry(report,
219 &hid->report_enum[HID_FEATURE_REPORT].report_list,
221 gb_hid_init_report(ghid, report);
224 static int __gb_hid_get_raw_report(struct hid_device *hid,
225 unsigned char report_number, __u8 *buf, size_t count,
226 unsigned char report_type)
228 struct gb_hid *ghid = hid->driver_data;
231 if (report_type == HID_OUTPUT_REPORT)
234 ret = gb_hid_get_report(ghid, report_type, report_number, buf, count);
241 static int __gb_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
242 size_t len, unsigned char report_type)
244 struct gb_hid *ghid = hid->driver_data;
245 int report_id = buf[0];
248 if (report_type == HID_INPUT_REPORT)
256 ret = gb_hid_set_report(ghid, report_type, report_id, buf, len);
257 if (report_id && ret >= 0)
258 ret++; /* add report_id to the number of transfered bytes */
263 static int gb_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
264 __u8 *buf, size_t len, unsigned char rtype,
268 case HID_REQ_GET_REPORT:
269 return __gb_hid_get_raw_report(hid, reportnum, buf, len, rtype);
270 case HID_REQ_SET_REPORT:
271 if (buf[0] != reportnum)
273 return __gb_hid_output_raw_report(hid, buf, len, rtype);
280 static int gb_hid_parse(struct hid_device *hid)
282 struct gb_hid *ghid = hid->driver_data;
287 rsize = le16_to_cpu(ghid->hdesc.wReportDescLength);
288 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
289 dbg_hid("weird size of report descriptor (%u)\n", rsize);
293 rdesc = kzalloc(rsize, GFP_KERNEL);
295 dbg_hid("couldn't allocate rdesc memory\n");
299 ret = gb_hid_get_report_desc(ghid, rdesc);
301 hid_err(hid, "reading report descriptor failed\n");
305 ret = hid_parse_report(hid, rdesc, rsize);
307 dbg_hid("parsing report descriptor failed\n");
315 static int gb_hid_start(struct hid_device *hid)
317 struct gb_hid *ghid = hid->driver_data;
318 unsigned int bufsize = HID_MIN_BUFFER_SIZE;
321 gb_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
322 gb_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
323 gb_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
325 if (bufsize > HID_MAX_BUFFER_SIZE)
326 bufsize = HID_MAX_BUFFER_SIZE;
328 ret = gb_hid_alloc_buffers(ghid, bufsize);
332 if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
333 gb_hid_init_reports(ghid);
338 static void gb_hid_stop(struct hid_device *hid)
340 struct gb_hid *ghid = hid->driver_data;
342 gb_hid_free_buffers(ghid);
345 static int gb_hid_open(struct hid_device *hid)
347 struct gb_hid *ghid = hid->driver_data;
350 ret = gb_hid_set_power(ghid, GB_HID_TYPE_PWR_ON);
354 set_bit(GB_HID_STARTED, &ghid->flags);
358 static void gb_hid_close(struct hid_device *hid)
360 struct gb_hid *ghid = hid->driver_data;
363 clear_bit(GB_HID_STARTED, &ghid->flags);
365 /* Save some power */
366 ret = gb_hid_set_power(ghid, GB_HID_TYPE_PWR_OFF);
368 dev_err(&ghid->connection->bundle->dev,
369 "failed to power off (%d)\n", ret);
372 static int gb_hid_power(struct hid_device *hid, int lvl)
374 struct gb_hid *ghid = hid->driver_data;
378 return gb_hid_set_power(ghid, GB_HID_TYPE_PWR_ON);
380 return gb_hid_set_power(ghid, GB_HID_TYPE_PWR_OFF);
386 /* HID structure to pass callbacks */
387 static struct hid_ll_driver gb_hid_ll_driver = {
388 .parse = gb_hid_parse,
389 .start = gb_hid_start,
392 .close = gb_hid_close,
393 .power = gb_hid_power,
394 .raw_request = gb_hid_raw_request,
397 static int gb_hid_init(struct gb_hid *ghid)
399 struct hid_device *hid = ghid->hid;
402 ret = gb_hid_get_desc(ghid);
406 hid->version = le16_to_cpu(ghid->hdesc.bcdHID);
407 hid->vendor = le16_to_cpu(ghid->hdesc.wVendorID);
408 hid->product = le16_to_cpu(ghid->hdesc.wProductID);
409 hid->country = ghid->hdesc.bCountryCode;
411 hid->driver_data = ghid;
412 hid->ll_driver = &gb_hid_ll_driver;
413 hid->dev.parent = &ghid->connection->bundle->dev;
414 // hid->bus = BUS_GREYBUS; /* Need a bustype for GREYBUS in <linux/input.h> */
416 /* Set HID device's name */
417 snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X",
418 dev_name(&ghid->connection->bundle->dev),
419 hid->vendor, hid->product);
424 static int gb_hid_probe(struct gb_bundle *bundle,
425 const struct greybus_bundle_id *id)
427 struct greybus_descriptor_cport *cport_desc;
428 struct gb_connection *connection;
429 struct hid_device *hid;
433 if (bundle->num_cports != 1)
436 cport_desc = &bundle->cport_desc[0];
437 if (cport_desc->protocol_id != GREYBUS_PROTOCOL_HID)
440 ghid = kzalloc(sizeof(*ghid), GFP_KERNEL);
444 connection = gb_connection_create(bundle, le16_to_cpu(cport_desc->id),
445 gb_hid_request_handler);
446 if (IS_ERR(connection)) {
447 ret = PTR_ERR(connection);
451 gb_connection_set_data(connection, ghid);
452 ghid->connection = connection;
454 hid = hid_allocate_device();
457 goto err_connection_destroy;
461 ghid->bundle = bundle;
463 greybus_set_drvdata(bundle, ghid);
465 ret = gb_connection_enable(connection);
467 goto err_destroy_hid;
469 ret = gb_hid_init(ghid);
471 goto err_connection_disable;
473 ret = hid_add_device(hid);
475 hid_err(hid, "can't add hid device: %d\n", ret);
476 goto err_connection_disable;
479 gb_pm_runtime_put_autosuspend(bundle);
483 err_connection_disable:
484 gb_connection_disable(connection);
486 hid_destroy_device(hid);
487 err_connection_destroy:
488 gb_connection_destroy(connection);
495 static void gb_hid_disconnect(struct gb_bundle *bundle)
497 struct gb_hid *ghid = greybus_get_drvdata(bundle);
499 if (gb_pm_runtime_get_sync(bundle))
500 gb_pm_runtime_get_noresume(bundle);
502 hid_destroy_device(ghid->hid);
503 gb_connection_disable(ghid->connection);
504 gb_connection_destroy(ghid->connection);
508 static const struct greybus_bundle_id gb_hid_id_table[] = {
509 { GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_HID) },
512 MODULE_DEVICE_TABLE(greybus, gb_hid_id_table);
514 static struct greybus_driver gb_hid_driver = {
516 .probe = gb_hid_probe,
517 .disconnect = gb_hid_disconnect,
518 .id_table = gb_hid_id_table,
520 module_greybus_driver(gb_hid_driver);
522 MODULE_LICENSE("GPL v2");