1 // SPDX-License-Identifier: GPL-2.0+
3  * Surface System Aggregator Module (SSAM) HID transport driver for the
5  * integrated HID devices on Surface Laptop 3, Book 3, and later.
7  * Copyright (C) 2019-2021 Blaž Hrastnik <[email protected]>,
23 /* -- SAM interface. -------------------------------------------------------- */
57 	buffer_len = ARRAY_SIZE(buffer) - sizeof(struct surface_hid_buffer_slice);  in ssam_hid_get_descriptor()
59 	rqst.target_category = shid->uid.category;  in ssam_hid_get_descriptor()
60 	rqst.target_id = shid->uid.target;  in ssam_hid_get_descriptor()
62 	rqst.instance_id = shid->uid.instance;  in ssam_hid_get_descriptor()
71 	slice->entry = entry;  in ssam_hid_get_descriptor()
72 	slice->end = 0;  in ssam_hid_get_descriptor()
77 	while (!slice->end && offset < len) {  in ssam_hid_get_descriptor()
78 		put_unaligned_le32(offset, &slice->offset);  in ssam_hid_get_descriptor()
79 		put_unaligned_le32(length, &slice->length);  in ssam_hid_get_descriptor()
83 		status = ssam_retry(ssam_request_do_sync_onstack, shid->ctrl, &rqst, &rsp,  in ssam_hid_get_descriptor()
88 		offset = get_unaligned_le32(&slice->offset);  in ssam_hid_get_descriptor()
89 		length = get_unaligned_le32(&slice->length);  in ssam_hid_get_descriptor()
93 			return -EPROTO;  in ssam_hid_get_descriptor()
96 			length = len - offset;  in ssam_hid_get_descriptor()
98 		memcpy(buf + offset, &slice->data[0], length);  in ssam_hid_get_descriptor()
105 		dev_err(shid->dev, "unexpected descriptor length: got %u, expected %zu\n",  in ssam_hid_get_descriptor()
107 		return -EPROTO;  in ssam_hid_get_descriptor()
124 	rqst.target_category = shid->uid.category;  in ssam_hid_set_raw_report()
125 	rqst.target_id = shid->uid.target;  in ssam_hid_set_raw_report()
126 	rqst.instance_id = shid->uid.instance;  in ssam_hid_set_raw_report()
134 	return ssam_retry(ssam_request_do_sync, shid->ctrl, &rqst, NULL);  in ssam_hid_set_raw_report()
142 	rqst.target_category = shid->uid.category;  in ssam_hid_get_raw_report()
143 	rqst.target_id = shid->uid.target;  in ssam_hid_get_raw_report()
144 	rqst.instance_id = shid->uid.instance;  in ssam_hid_get_raw_report()
154 	return ssam_retry(ssam_request_do_sync_onstack, shid->ctrl, &rqst, &rsp, sizeof(rprt_id));  in ssam_hid_get_raw_report()
161 	if (event->command_id != 0x00)  in ssam_hid_event_fn()
164 	hid_input_report(shid->hid, HID_INPUT_REPORT, (u8 *)&event->data[0], event->length, 0);  in ssam_hid_event_fn()
169 /* -- Transport driver. ----------------------------------------------------- */
196 /* -- Driver setup. --------------------------------------------------------- */
202 	shid = devm_kzalloc(&sdev->dev, sizeof(*shid), GFP_KERNEL);  in surface_hid_probe()
204 		return -ENOMEM;  in surface_hid_probe()
206 	shid->dev = &sdev->dev;  in surface_hid_probe()
207 	shid->ctrl = sdev->ctrl;  in surface_hid_probe()
208 	shid->uid = sdev->uid;  in surface_hid_probe()
210 	shid->notif.base.priority = 1;  in surface_hid_probe()
211 	shid->notif.base.fn = ssam_hid_event_fn;  in surface_hid_probe()
212 	shid->notif.event.reg = SSAM_EVENT_REGISTRY_REG(sdev->uid.target);  in surface_hid_probe()
213 	shid->notif.event.id.target_category = sdev->uid.category;  in surface_hid_probe()
214 	shid->notif.event.id.instance = sdev->uid.instance;  in surface_hid_probe()
215 	shid->notif.event.mask = SSAM_EVENT_MASK_STRICT;  in surface_hid_probe()
216 	shid->notif.event.flags = 0;  in surface_hid_probe()
218 	shid->ops.get_descriptor = ssam_hid_get_descriptor;  in surface_hid_probe()
219 	shid->ops.output_report = shid_output_report;  in surface_hid_probe()
220 	shid->ops.get_feature_report = shid_get_feature_report;  in surface_hid_probe()
221 	shid->ops.set_feature_report = shid_set_feature_report;  in surface_hid_probe()
252 MODULE_DESCRIPTION("HID transport driver for Surface System Aggregator Module");