From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/hid/surface-hid/surface_hid.c | 253 ++++++++++++++++++++++++++++++++++ 1 file changed, 253 insertions(+) create mode 100644 drivers/hid/surface-hid/surface_hid.c (limited to 'drivers/hid/surface-hid/surface_hid.c') diff --git a/drivers/hid/surface-hid/surface_hid.c b/drivers/hid/surface-hid/surface_hid.c new file mode 100644 index 0000000000..61e5814b0a --- /dev/null +++ b/drivers/hid/surface-hid/surface_hid.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Surface System Aggregator Module (SSAM) HID transport driver for the + * generic HID interface (HID/TC=0x15 subsystem). Provides support for + * integrated HID devices on Surface Laptop 3, Book 3, and later. + * + * Copyright (C) 2019-2021 Blaž Hrastnik , + * Maximilian Luz + */ + +#include +#include +#include +#include +#include + +#include +#include + +#include "surface_hid_core.h" + + +/* -- SAM interface. -------------------------------------------------------- */ + +struct surface_hid_buffer_slice { + __u8 entry; + __le32 offset; + __le32 length; + __u8 end; + __u8 data[]; +} __packed; + +static_assert(sizeof(struct surface_hid_buffer_slice) == 10); + +enum surface_hid_cid { + SURFACE_HID_CID_OUTPUT_REPORT = 0x01, + SURFACE_HID_CID_GET_FEATURE_REPORT = 0x02, + SURFACE_HID_CID_SET_FEATURE_REPORT = 0x03, + SURFACE_HID_CID_GET_DESCRIPTOR = 0x04, +}; + +static int ssam_hid_get_descriptor(struct surface_hid_device *shid, u8 entry, u8 *buf, size_t len) +{ + u8 buffer[sizeof(struct surface_hid_buffer_slice) + 0x76]; + struct surface_hid_buffer_slice *slice; + struct ssam_request rqst; + struct ssam_response rsp; + u32 buffer_len, offset, length; + int status; + + /* + * Note: The 0x76 above has been chosen because that's what's used by + * the Windows driver. Together with the header, this leads to a 128 + * byte payload in total. + */ + + buffer_len = ARRAY_SIZE(buffer) - sizeof(struct surface_hid_buffer_slice); + + rqst.target_category = shid->uid.category; + rqst.target_id = shid->uid.target; + rqst.command_id = SURFACE_HID_CID_GET_DESCRIPTOR; + rqst.instance_id = shid->uid.instance; + rqst.flags = SSAM_REQUEST_HAS_RESPONSE; + rqst.length = sizeof(struct surface_hid_buffer_slice); + rqst.payload = buffer; + + rsp.capacity = ARRAY_SIZE(buffer); + rsp.pointer = buffer; + + slice = (struct surface_hid_buffer_slice *)buffer; + slice->entry = entry; + slice->end = 0; + + offset = 0; + length = buffer_len; + + while (!slice->end && offset < len) { + put_unaligned_le32(offset, &slice->offset); + put_unaligned_le32(length, &slice->length); + + rsp.length = 0; + + status = ssam_retry(ssam_request_do_sync_onstack, shid->ctrl, &rqst, &rsp, + sizeof(*slice)); + if (status) + return status; + + offset = get_unaligned_le32(&slice->offset); + length = get_unaligned_le32(&slice->length); + + /* Don't mess stuff up in case we receive garbage. */ + if (length > buffer_len || offset > len) + return -EPROTO; + + if (offset + length > len) + length = len - offset; + + memcpy(buf + offset, &slice->data[0], length); + + offset += length; + length = buffer_len; + } + + if (offset != len) { + dev_err(shid->dev, "unexpected descriptor length: got %u, expected %zu\n", + offset, len); + return -EPROTO; + } + + return 0; +} + +static int ssam_hid_set_raw_report(struct surface_hid_device *shid, u8 rprt_id, bool feature, + u8 *buf, size_t len) +{ + struct ssam_request rqst; + u8 cid; + + if (feature) + cid = SURFACE_HID_CID_SET_FEATURE_REPORT; + else + cid = SURFACE_HID_CID_OUTPUT_REPORT; + + rqst.target_category = shid->uid.category; + rqst.target_id = shid->uid.target; + rqst.instance_id = shid->uid.instance; + rqst.command_id = cid; + rqst.flags = 0; + rqst.length = len; + rqst.payload = buf; + + buf[0] = rprt_id; + + return ssam_retry(ssam_request_do_sync, shid->ctrl, &rqst, NULL); +} + +static int ssam_hid_get_raw_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len) +{ + struct ssam_request rqst; + struct ssam_response rsp; + + rqst.target_category = shid->uid.category; + rqst.target_id = shid->uid.target; + rqst.instance_id = shid->uid.instance; + rqst.command_id = SURFACE_HID_CID_GET_FEATURE_REPORT; + rqst.flags = SSAM_REQUEST_HAS_RESPONSE; + rqst.length = sizeof(rprt_id); + rqst.payload = &rprt_id; + + rsp.capacity = len; + rsp.length = 0; + rsp.pointer = buf; + + return ssam_retry(ssam_request_do_sync_onstack, shid->ctrl, &rqst, &rsp, sizeof(rprt_id)); +} + +static u32 ssam_hid_event_fn(struct ssam_event_notifier *nf, const struct ssam_event *event) +{ + struct surface_hid_device *shid = container_of(nf, struct surface_hid_device, notif); + + if (event->command_id != 0x00) + return 0; + + hid_input_report(shid->hid, HID_INPUT_REPORT, (u8 *)&event->data[0], event->length, 0); + return SSAM_NOTIF_HANDLED; +} + + +/* -- Transport driver. ----------------------------------------------------- */ + +static int shid_output_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len) +{ + int status; + + status = ssam_hid_set_raw_report(shid, rprt_id, false, buf, len); + return status >= 0 ? len : status; +} + +static int shid_get_feature_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len) +{ + int status; + + status = ssam_hid_get_raw_report(shid, rprt_id, buf, len); + return status >= 0 ? len : status; +} + +static int shid_set_feature_report(struct surface_hid_device *shid, u8 rprt_id, u8 *buf, size_t len) +{ + int status; + + status = ssam_hid_set_raw_report(shid, rprt_id, true, buf, len); + return status >= 0 ? len : status; +} + + +/* -- Driver setup. --------------------------------------------------------- */ + +static int surface_hid_probe(struct ssam_device *sdev) +{ + struct surface_hid_device *shid; + + shid = devm_kzalloc(&sdev->dev, sizeof(*shid), GFP_KERNEL); + if (!shid) + return -ENOMEM; + + shid->dev = &sdev->dev; + shid->ctrl = sdev->ctrl; + shid->uid = sdev->uid; + + shid->notif.base.priority = 1; + shid->notif.base.fn = ssam_hid_event_fn; + shid->notif.event.reg = SSAM_EVENT_REGISTRY_REG(sdev->uid.target); + shid->notif.event.id.target_category = sdev->uid.category; + shid->notif.event.id.instance = sdev->uid.instance; + shid->notif.event.mask = SSAM_EVENT_MASK_STRICT; + shid->notif.event.flags = 0; + + shid->ops.get_descriptor = ssam_hid_get_descriptor; + shid->ops.output_report = shid_output_report; + shid->ops.get_feature_report = shid_get_feature_report; + shid->ops.set_feature_report = shid_set_feature_report; + + ssam_device_set_drvdata(sdev, shid); + return surface_hid_device_add(shid); +} + +static void surface_hid_remove(struct ssam_device *sdev) +{ + surface_hid_device_destroy(ssam_device_get_drvdata(sdev)); +} + +static const struct ssam_device_id surface_hid_match[] = { + { SSAM_SDEV(HID, ANY, SSAM_SSH_IID_ANY, 0x00) }, + { }, +}; +MODULE_DEVICE_TABLE(ssam, surface_hid_match); + +static struct ssam_device_driver surface_hid_driver = { + .probe = surface_hid_probe, + .remove = surface_hid_remove, + .match_table = surface_hid_match, + .driver = { + .name = "surface_hid", + .pm = &surface_hid_pm_ops, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, +}; +module_ssam_device_driver(surface_hid_driver); + +MODULE_AUTHOR("Blaž Hrastnik "); +MODULE_AUTHOR("Maximilian Luz "); +MODULE_DESCRIPTION("HID transport driver for Surface System Aggregator Module"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3