// SPDX-License-Identifier: GPL-2.0-or-later /* * HID support for Linux * * Copyright (c) 1999 Andreas Gal * Copyright (c) 2000-2005 Vojtech Pavlik * Copyright (c) 2005 Michael Haboustak for Concept2, Inc * Copyright (c) 2006-2012 Jiri Kosina */ /* */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "hid-ids.h" /* * Version Information */ #define DRIVER_DESC "HID core driver" int hid_debug = 0; module_param_named(debug, hid_debug, int, 0600); MODULE_PARM_DESC(debug, "toggle HID debugging messages"); EXPORT_SYMBOL_GPL(hid_debug); static int hid_ignore_special_drivers = 0; module_param_named(ignore_special_drivers, hid_ignore_special_drivers, int, 0600); MODULE_PARM_DESC(ignore_special_drivers, "Ignore any special drivers and handle all devices by generic driver"); /* * Register a new report for a device. */ struct hid_report *hid_register_report(struct hid_device *device, unsigned int type, unsigned int id, unsigned int application) { struct hid_report_enum *report_enum = device->report_enum + type; struct hid_report *report; if (id >= HID_MAX_IDS) return NULL; if (report_enum->report_id_hash[id]) return report_enum->report_id_hash[id]; report = kzalloc(sizeof(struct hid_report), GFP_KERNEL); if (!report) return NULL; if (id != 0) report_enum->numbered = 1; report->id = id; report->type = type; report->size = 0; report->device = device; report->application = application; report_enum->report_id_hash[id] = report; list_add_tail(&report->list, &report_enum->report_list); return report; } EXPORT_SYMBOL_GPL(hid_register_report); /* * Register a new field for this report. */ static struct hid_field *hid_register_field(struct hid_report *report, unsigned usages, unsigned values) { struct hid_field *field; if (report->maxfield == HID_MAX_FIELDS) { hid_err(report->device, "too many fields in report\n"); return NULL; } field = kzalloc((sizeof(struct hid_field) + usages * sizeof(struct hid_usage) + values * sizeof(unsigned)), GFP_KERNEL); if (!field) return NULL; field->index = report->maxfield++; report->field[field->index] = field; field->usage = (struct hid_usage *)(field + 1); field->value = (s32 *)(field->usage + usages); field->report = report; return field; } /* * Open a collection. The type/usage is pushed on the stack. */ static int open_collection(struct hid_parser *parser, unsigned type) { struct hid_collection *collection; unsigned usage; int collection_index; usage = parser->local.usage[0]; if (parser->collection_stack_ptr == parser->collection_stack_size) { unsigned int *collection_stack; unsigned int new_size = parser->collection_stack_size + HID_COLLECTION_STACK_SIZE; collection_stack = krealloc(parser->collection_stack, new_size * sizeof(unsigned int), GFP_KERNEL); if (!collection_stack) return -ENOMEM; parser->collection_stack = collection_stack; parser->collection_stack_size = new_size; } if (parser->device->maxcollection == parser->device->collection_size) { collection = kmalloc( array3_size(sizeof(struct hid_collection), parser->device->collection_size, 2), GFP_KERNEL); if (collection == NULL) { hid_err(parser->device, "failed to reallocate collection array\n"); return -ENOMEM; } memcpy(collection, parser->device->collection, sizeof(struct hid_collection) * parser->device->collection_size); memset(collection + parser->device->collection_size, 0, sizeof(struct hid_collection) * parser->device->collection_size); kfree(parser->device->collection); parser->device->collection = collection; parser->device->collection_size *= 2; } parser->collection_stack[parser->collection_stack_ptr++] = parser->device->maxcollection; collection_index = parser->device->maxcollection++; collection = parser->device->collection + collection_index; collection->type = type; collection->usage = usage; collection->level = parser->collection_stack_ptr - 1; collection->parent_idx = (collection->level == 0) ? -1 : parser->collection_stack[collection->level - 1]; if (type == HID_COLLECTION_APPLICATION) parser->device->maxapplication++; return 0; } /* * Close a collection. */ static int close_collection(struct hid_parser *parser) { if (!parser->collection_stack_ptr) { hid_err(parser->device, "collection stack underflow\n"); return -EINVAL; } parser->collection_stack_ptr--; return 0; } /* * Climb up the stack, search for the specified collection type * and return the usage. */ static unsigned hid_lookup_collection(struct hid_parser *parser, unsigned type) { struct hid_collection *collection = parser->device->collection; int n; for (n = parser->collection_stack_ptr - 1; n >= 0; n--) { unsigned index = parser->collection_stack[n]; if (collection[index].type == type) return collection[index].usage; } return 0; /* we know nothing about this usage type */ } /* * Add a usage to the temporary parser table. */ static int hid_add_usage(struct hid_parser *parser, unsigned usage, u8 size) { if (parser->local.usage_index >= HID_MAX_USAGES) { hid_err(parser->device, "usage index exceeded\n"); return -1; } parser->local.usage[parser->local.usage_index] = usage; parser->local.usage_size[parser->local.usage_index] = size; parser->local.collection_index[parser->local.usage_index] = parser->collection_stack_ptr ? parser->collection_stack[parser->collection_stack_ptr - 1] : 0; parser->local.usage_index++; return 0; } /* * Register a new field for this report. */ static int hid_add_field(struct hid_parser *parser, unsigned report_type, unsigned flags) { struct hid_report *report; struct hid_field *field; unsigned int usages; unsigned int offset; unsigned int i; unsigned int application; application = hid_lookup_collection(parser, HID_COLLECTION_APPLICATION); report = hid_register_report(parser->device, report_type, parser->global.report_id, application); if (!report) { hid_err(parser->device, "hid_register_report failed\n"); return -1; } /* Handle both signed and unsigned cases properly */ if ((parser->global.logical_minimum < 0 && parser->global.logical_maximum < parser->global.logical_minimum) || (parser->global.logical_minimum >= 0 && (__u32)parser->global.logical_maximum < (__u32)parser->global.logical_minimum)) { dbg_hid("logical range invalid 0x%x 0x%x\n", parser->global.logical_minimum, parser->global.logical_maximum); return -1; } offset = report->size; report->size += parser->global.report_size * parser->global.report_count; if (!parser->local.usage_index) /* Ignore padding fields */ return 0; usages = max_t(unsigned, parser->local.usage_index, parser->global.report_count); field = hid_register_field(report, usages, parser->global.report_count); if (!field) return 0; field->physical = hid_lookup_collection(parser, HID_COLLECTION_PHYSICAL); field->logical = hid_lookup_collection(parser, HID_COLLECTION_LOGICAL); field->application = application; for (i = 0; i < usages; i++) { unsigned j = i; /* Duplicate the last usage we parsed if we have excess values */ if (i >= parser->local.usage_index) j = parser->local.usage_index - 1; field->usage[i].hid = parser->local.usage[j]; field->usage[i].collection_index = parser->local.collection_index[j]; field->usage[i].usage_index = i; field->usage[i].resolution_multiplier = 1; } field->maxusage = usages; field->flags = flags; field->report_offset = offset; field->report_type = report_type; field->report_size = parser->global.report_size; field->report_count = parser->global.report_count; field->logical_minimum = parser->global.logical_minimum; field->logical_maximum = parser->global.logical_maximum; field->physical_minimum = parser->global.physical_minimum; field->physical_maximum = parser->global.physical_maximum; field->unit_exponent = parser->global.unit_exponent; field->unit = parser->global.unit; return 0; } /* * Read data value from item. */ static u32 item_udata(struct hid_item *item) { switch (item->size) { case 1: return item->data.u8; case 2: return item->data.u16; case 4: return item->data.u32; } return 0; } static s32 item_sdata(struct hid_item *item) { switch (item->size) { case 1: return item->data.s8; case 2: return item->data.s16; case 4: return item->data.s32; } return 0; } /* * Process a global item. */ static int hid_parser_global(struct hid_parser *parser, struct hid_item *item) { __s32 raw_value; switch (item->tag) { case HID_GLOBAL_ITEM_TAG_PUSH: if (parser->global_stack_ptr == HID_GLOBAL_STACK_SIZE) { hid_err(parser->device, "global environment stack overflow\n"); return -1; } memcpy(parser->global_stack + parser->global_stack_ptr++, &parser->global, sizeof(struct hid_global)); return 0; case HID_GLOBAL_ITEM_TAG_POP: if (!parser->global_stack_ptr) { hid_err(parser->device, "global environment stack underflow\n"); return -1; } memcpy(&parser->global, parser->global_stack + --parser->global_stack_ptr, sizeof(struct hid_global)); return 0; case HID_GLOBAL_ITEM_TAG_USAGE_PAGE: parser->global.usage_page = item_udata(item); return 0; case HID_GLOBAL_ITEM_TAG_LOGICAL_MINIMUM: parser->global.logical_minimum = item_sdata(item); return 0; case HID_GLOBAL_ITEM_TAG_LOGICAL_MAXIMUM: if (parser->global.logical_minimum < 0) parser->global.logical_maximum = item_sdata(item); else parser->global.logical_maximum = item_udata(item); return 0; case HID_GLOBAL_ITEM_TAG_PHYSICAL_MINIMUM: parser->global.physical_minimum = item_sdata(item); return 0; case HID_GLOBAL_ITEM_TAG_PHYSICAL_MAXIMUM: if (parser->global.physical_minimum < 0) parser->global.physical_maximum = item_sdata(item); else parser->global.physical_maximum = item_udata(item); return 0; case HID_GLOBAL_ITEM_TAG_UNIT_EXPONENT: /* Many devices provide unit exponent as a two's complement * nibble due to the common misunderstanding of HID * specification 1.11, 6.2.2.7 Global Items. Attempt to handle * both this and the standard encoding. */ raw_value = item_sdata(item); if (!(raw_value & 0xfffffff0)) parser->global.unit_exponent = hid_snto32(raw_value, 4); else parser->global.unit_exponent = raw_value; return 0; case HID_GLOBAL_ITEM_TAG_UNIT: parser->global.unit = item_udata(item); return 0; case HID_GLOBAL_ITEM_TAG_REPORT_SIZE: parser->global.report_size = item_udata(item); if (parser->global.report_size > 256) { hid_err(parser->device, "invalid report_size %d\n", parser->global.report_size); return -1; } return 0; case HID_GLOBAL_ITEM_TAG_REPORT_COUNT: parser->global.report_count = item_udata(item); if (parser->global.report_count > HID_MAX_USAGES) { hid_err(parser->device, "invalid report_count %d\n", parser->global.report_count); return -1; } return 0; case HID_GLOBAL_ITEM_TAG_REPORT_ID: parser->global.report_id = item_udata(item); if (parser->global.report_id == 0 || parser->global.report_id >= HID_MAX_IDS) { hid_err(parser->device, "report_id %u is invalid\n", parser->global.report_id); return -1; } return 0; default: hid_err(parser->device, "unknown global tag 0x%x\n", item->tag); return -1; } } /* * Process a local item. */ static int hid_parser_local(struct hid_parser *parser, struct hid_item *item) { __u32 data; unsigned n; __u32 count; data = item_udata(item); switch (item->tag) { case HID_LOCAL_ITEM_TAG_DELIMITER: if (data) { /* * We treat items before the first delimiter * as global to all usage sets (branch 0). * In the moment we process only these global * items and the first delimiter set. */ if (parser->local.delimiter_depth != 0) { hid_err(parser->device, "nested delimiters\n"); return -1; } parser->local.delimiter_depth++; parser->local.delimiter_branch++; } else { if (parser->local.delimiter_depth < 1) { hid_err(parser->device, "bogus close delimiter\n"); return -1; } parser->local.delimiter_depth--; } return 0; case HID_LOCAL_ITEM_TAG_USAGE: if (parser->local.delimiter_branch > 1) { dbg_hid("alternative usage ignored\n"); return 0; } return hid_add_usage(parser, data, item->size); case HID_LOCAL_ITEM_TAG_USAGE_MINIMUM: if (parser->local.delimiter_branch > 1) { dbg_hid("alternative usage ignored\n"); return 0; } parser->local.usage_minimum = data; return 0; case HID_LOCAL_ITEM_TAG_USAGE_MAXIMUM: if (parser->local.delimiter_branch > 1) { dbg_hid("alternative usage ignored\n"); return 0; } count = data - parser->local.usage_minimum; if (count + parser->local.usage_index >= HID_MAX_USAGES) { /* * We do not warn if the name is not set, we are * actually pre-scanning the device. */ if (dev_name(&parser->device->dev)) hid_warn(parser->device, "ignoring exceeding usage max\n"); data = HID_MAX_USAGES - parser->local.usage_index + parser->local.usage_minimum - 1; if (data <= 0) { hid_err(parser->device, "no more usage index available\n"); return -1; } } for (n = parser->local.usage_minimum; n <= data; n++) if (hid_add_usage(parser, n, item->size)) { dbg_hid("hid_add_usage failed\n"); return -1; } return 0; default: dbg_hid("unknown local item tag 0x%x\n", item->tag); return 0; } return 0; } /* * Concatenate Usage Pages into Usages where relevant: * As per specification, 6.2.2.8: "When the parser encounters a main item it * concatenates the last declared Usage Page with a Usage to form a complete * usage value." */ static void hid_concatenate_usage_page(struct hid_parser *parser) { int i; for (i = 0; i < parser->local.usage_index; i++) if (parser->local.usage_size[i] <= 2) parser->local.usage[i] += parser->global.usage_page << 16; } /* * Process a main item. */ static int hid_parser_main(struct hid_parser *parser, struct hid_item *item) { __u32 data; int ret; hid_concatenate_usage_page(parser); data = item_udata(item); switch (item->tag) { case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: ret = open_collection(parser, data & 0xff); break; case HID_MAIN_ITEM_TAG_END_COLLECTION: ret = close_collection(parser); break; case HID_MAIN_ITEM_TAG_INPUT: ret = hid_add_field(parser, HID_INPUT_REPORT, data); break; case HID_MAIN_ITEM_TAG_OUTPUT: ret = hid_add_field(parser, HID_OUTPUT_REPORT, data); break; case HID_MAIN_ITEM_TAG_FEATURE: ret = hid_add_field(parser, HID_FEATURE_REPORT, data); break; default: hid_warn(parser->device, "unknown main item tag 0x%x\n", item->tag); ret = 0; } memset(&parser->local, 0, sizeof(parser->local)); /* Reset the local parser environment */ return ret; } /* * Process a reserved item. */ static int hid_parser_reserved(struct hid_parser *parser, struct hid_item *item) { dbg_hid("reserved item type, tag 0x%x\n", item->tag); return 0; } /* * Free a report and all registered fields. The field->usage and * field->value table's are allocated behind the field, so we need * only to free(field) itself. */ static void hid_free_report(struct hid_report *report) { unsigned n; for (n = 0; n < report->maxfield; n++) kfree(report->field[n]); kfree(report); } /* * Close report. This function returns the device * state to the point prior to hid_open_report(). */ static void hid_close_report(struct hid_device *device) { unsigned i, j; for (i = 0; i < HID_REPORT_TYPES; i++) { struct hid_report_enum *report_enum = device->report_enum + i; for (j = 0; j < HID_MAX_IDS; j++) { struct hid_report *report = report_enum->report_id_hash[j]; if (report) hid_free_report(report); } memset(report_enum, 0, sizeof(*report_enum)); INIT_LIST_HEAD(&report_enum->report_list); } kfree(device->rdesc); device->rdesc = NULL; device->rsize = 0; kfree(device->collection); device->collection = NULL; device->collection_size = 0; device->maxcollection = 0; device->maxapplication = 0; device->status &= ~HID_STAT_PARSED; } /* * Free a device structure, all reports, and all fields. */ static void hid_device_release(struct device *dev) { struct hid_device *hid = to_hid_device(dev); hid_close_report(hid); kfree(hid->dev_rdesc); kfree(hid); } /* * Fetch a report description item from the data stream. We support long * items, though they are not used yet. */ static u8 *fetch_item(__u8 *start, __u8 *end, struct hid_item *item) { u8 b; if ((end - start) <= 0) return NULL; b = *start++; item->type = (b >> 2) & 3; item->tag = (b >> 4) & 15; if (item->tag == HID_ITEM_TAG_LONG) { item->format = HID_ITEM_FORMAT_LONG; if ((end - start) < 2) return NULL; item->size = *start++; item->tag = *start++; if ((end - start) < item->size) return NULL; item->data.longdata = start; start += item->size; return start; } item->format = HID_ITEM_FORMAT_SHORT; item->size = b & 3; switch (item->size) { case 0: return start; case 1: if ((end - start) < 1) return NULL; item->data.u8 = *start++; return start; case 2: if ((end - start) < 2) return NULL; item->data.u16 = get_unaligned_le16(start); start = (__u8 *)((__le16 *)start + 1); return start; case 3: item->size++; if ((end - start) < 4) return NULL; item->data.u32 = get_unaligned_le32(start); start = (__u8 *)((__le32 *)start + 1); return start; } return NULL; } static void hid_scan_input_usage(struct hid_parser *parser, u32 usage) { struct hid_device *hid = parser->device; if (usage == HID_DG_CONTACTID) hid->group = HID_GROUP_MULTITOUCH; } static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage) { if (usage == 0xff0000c5 && parser->global.report_count == 256 && parser->global.report_size == 8) parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8; } static void hid_scan_collection(struct hid_parser *parser, unsigned type) { struct hid_device *hid = parser->device; int i; if (((parser->global.usage_page << 16) == HID_UP_SENSOR) && type == HID_COLLECTION_PHYSICAL) hid->group = HID_GROUP_SENSOR_HUB; if (hid->vendor == USB_VENDOR_ID_MICROSOFT && hid->product == USB_DEVICE_ID_MS_POWER_COVER && hid->group == HID_GROUP_MULTITOUCH) hid->group = HID_GROUP_GENERIC; if ((parser->global.usage_page << 16) == HID_UP_GENDESK) for (i = 0; i < parser->local.usage_index; i++) if (parser->local.usage[i] == HID_GD_POINTER) parser->scan_flags |= HID_SCAN_FLAG_GD_POINTER; if ((parser->global.usage_page << 16) >= HID_UP_MSVENDOR) parser->scan_flags |= HID_SCAN_FLAG_VENDOR_SPECIFIC; } static int hid_scan_main(struct hid_parser *parser, struct hid_item *item) { __u32 data; int i; hid_concatenate_usage_page(parser); data = item_udata(item); switch (item->tag) { case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION: hid_scan_collection(parser, data & 0xff); break; case HID_MAIN_ITEM_TAG_END_COLLECTION: break; case HID_MAIN_ITEM_TAG_INPUT: /* ignore constant inputs, they will be ignored by hid-input */ if (data & HID_MAIN_ITEM_CONSTANT) break; for (i = 0; i < parser->local.usage_index; i++) hid_scan_input_usage(parser, parser->local.usage[i]); break; case HID_MAIN_ITEM_TAG_OUTPUT: break; case HID_MAIN_ITEM_TAG_FEATURE: for (i = 0; i < parser->local.usage_index; i++) hid_scan_feature_usage(parser, parser->local.usage[i]); break; } /* Reset the local parser environment */ memset(&parser->local, 0, sizeof(parser->local)); return 0; } /* * Scan a report descriptor before the device is added to the bus. * Sets device groups and other properties that determine what driver * to load. */ static int hid_scan_report(struct hid_device *hid) { struct hid_parser *parser; struct hid_item item; __u8 *start = hid->dev_rdesc; __u8 *end = start + hid->dev_rsize; static int (*dispatch_type[])(struct hid_parser *parser, struct hid_item *item) = { hid_scan_main, hid_parser_global, hid_parser_local, hid_parser_reserved }; parser = vzalloc(sizeof(struct hid_parser)); if (!parser) return -ENOMEM; parser->device = hid; hid->group = HID_GROUP_GENERIC; /* * The parsing is simpler than the one in hid_open_report() as we should * be robust against hid errors. Those errors will be raised by * hid_open_report() anyway. */ while ((start = fetch_item(start, end, &item)) != NULL) dispatch_type[item.type](parser, &item); /* * Handle special flags set during scanning. */ if ((parser->scan_flags & HID_SCAN_FLAG_MT_WIN_8) && (hid->group == HID_GROUP_MULTITOUCH)) hid->group = HID_GROUP_MULTITOUCH_WIN_8; /* * Vendor specific handlings */ switch (hid->vendor) { case USB_VENDOR_ID_WACOM: hid->group = HID_GROUP_WACOM; break; case USB_VENDOR_ID_SYNAPTICS: if (hid->group == HID_GROUP_GENERIC) if ((parser->scan_flags & HID_SCAN_FLAG_VENDOR_SPECIFIC) && (parser->scan_flags & HID_SCAN_FLAG_GD_POINTER)) /* * hid-rmi should take care of them, * not hid-generic */ hid->group = HID_GROUP_RMI; break; } kfree(parser->collection_stack); vfree(parser); return 0; } /** * hid_parse_report - parse device report * * @device: hid device * @start: report start * @size: report size * * Allocate the device report as read by the bus driver. This function should * only be called from parse() in ll drivers. */ int hid_parse_report(struct hid_device *hid, __u8 *start, unsigned size) { hid->dev_rdesc = kmemdup(start, size, GFP_KERNEL); if (!hid->dev_rdesc) return -ENOMEM; hid->dev_rsize = size; return 0; } EXPORT_SYMBOL_GPL(hid_parse_report); static const char * const hid_report_names[] = { "HID_INPUT_REPORT", "HID_OUTPUT_REPORT", "HID_FEATURE_REPORT", }; /** * hid_validate_values - validate existing device report's value indexes * * @device: hid device * @type: which report type to examine * @id: which report ID to examine (0 for first) * @field_index: which report field to examine * @report_counts: expected number of values * * Validate the number of values in a given field of a given report, after * parsing. */ struct hid_report *hid_validate_values(struct hid_device *hid, unsigned int type, unsigned int id, unsigned int field_index, unsigned int report_counts) { struct hid_report *report; if (type > HID_FEATURE_REPORT) { hid_err(hid, "invalid HID report type %u\n", type); return NULL; } if (id >= HID_MAX_IDS) { hid_err(hid, "invalid HID report id %u\n", id); return NULL; } /* * Explicitly not using hid_get_report() here since it depends on * ->numbered being checked, which may not always be the case when * drivers go to access report values. */ if (id == 0) { /* * Validating on id 0 means we should examine the first * report in the list. */ report = list_entry( hid->report_enum[type].report_list.next, struct hid_report, list); } else { report = hid->report_enum[type].report_id_hash[id]; } if (!report) { hid_err(hid, "missing %s %u\n", hid_report_names[type], id); return NULL; } if (report->maxfield <= field_index) { hid_err(hid, "not enough fields in %s %u\n", hid_report_names[type], id); return NULL; } if (report->field[field_index]->report_count < report_counts) { hid_err(hid, "not enough values in %s %u field %u\n", hid_report_names[type], id, field_index); return NULL; } return report; } EXPORT_SYMBOL_GPL(hid_validate_values); static int hid_calculate_multiplier(struct hid_device *hid, struct hid_field *multiplier) { int m; __s32 v = *multiplier->value; __s32 lmin = multiplier->logical_minimum; __s32 lmax = multiplier->logical_maximum; __s32 pmin = multiplier->physical_minimum; __s32 pmax = multiplier->physical_maximum; /* * "Because OS implementations will generally divide the control's * reported count by the Effective Resolution Multiplier, designers * should take care not to establish a potential Effective * Resolution Multiplier of zero." * HID Usage Table, v1.12, Section 4.3.1, p31 */ if (lmax - lmin == 0) return 1; /* * Handling the unit exponent is left as an exercise to whoever * finds a device where that exponent is not 0. */ m = ((v - lmin)/(lmax - lmin) * (pmax - pmin) + pmin); if (unlikely(multiplier->unit_exponent != 0)) { hid_warn(hid, "unsupported Resolution Multiplier unit exponent %d\n", multiplier->unit_exponent); } /* There are no devices with an effective multiplier > 255 */ if (unlikely(m == 0 || m > 255 || m < -255)) { hid_warn(hid, "unsupported Resolution Multiplier %d\n", m); m = 1; } return m; } static void hid_apply_multiplier_to_field(struct hid_device *hid, struct hid_field *field, struct hid_collection *multiplier_collection, int effective_multiplier) { struct hid_collection *collection; struct hid_usage *usage; int i; /* * If multiplier_collection is NULL, the multiplier applies * to all fields in the report. * Otherwise, it is the Logical Collection the multiplier applies to * but our field may be in a subcollection of that collection. */ for (i = 0; i < field->maxusage; i++) { usage = &field->usage[i]; collection = &hid->collection[usage->collection_index]; while (collection->parent_idx != -1 && collection != multiplier_collection) collection = &hid->collection[collection->parent_idx]; if (collection->parent_idx != -1 || multiplier_collection == NULL) usage->resolution_multiplier = effective_multiplier; } } static void hid_apply_multiplier(struct hid_device *hid, struct hid_field *multiplier) { struct hid_report_enum *rep_enum; struct hid_report *rep; struct hid_field *field; struct hid_collection *multiplier_collection; int effective_multiplier; int i; /* * "The Resolution Multiplier control must be contained in the same * Logical Collection as the control(s) to which it is to be applied. * If no Resolution Multiplier is defined, then the Resolution * Multiplier defaults to 1. If more than one control exists in a * Logical Collection, the Resolution Multiplier is associated with * all controls in the collection. If no Logical Collection is * defined, the Resolution Multiplier is associated with all * controls in the report." * HID Usage Table, v1.12, Section 4.3.1, p30 * * Thus, search from the current collection upwards until we find a * logical collection. Then search all fields for that same parent * collection. Those are the fields the multiplier applies to. * * If we have more than one multiplier, it will overwrite the * applicable fields later. */ multiplier_collection = &hid->collection[multiplier->usage->collection_index]; while (multiplier_collection->parent_idx != -1 && multiplier_collection->type != HID_COLLECTION_LOGICAL) multiplier_collection = &hid->collection[multiplier_collection->parent_idx]; effective_multiplier = hid_calculate_multiplier(hid, multiplier); rep_enum = &hid->report_enum[HID_INPUT_REPORT]; list_for_each_entry(rep, &rep_enum->report_list, list) { for (i = 0; i < rep->maxfield; i++) { field = rep->field[i]; hid_apply_multiplier_to_field(hid, field, multiplier_collection, effective_multiplier); } } } /* * hid_setup_resolution_multiplier - set up all resolution multipliers * * @device: hid device * * Search for all Resolution Multiplier Feature Reports and apply their * value to all matching Input items. This only updates the internal struct * fields. * * The Resolution Multiplier is applied by the hardware. If the multiplier * is anything other than 1, the hardware will send pre-multiplied events * so that the same physical interaction generates an accumulated * accumulated_value = value * * multiplier * This may be achieved by sending * - "value * multiplier" for each event, or * - "value" but "multiplier" times as frequently, or * - a combination of the above * The only guarantee is that the same physical interaction always generates * an accumulated 'value * multiplier'. * * This function must be called before any event processing and after * any SetRequest to the Resolution Multiplier. */ void hid_setup_resolution_multiplier(struct hid_device *hid) { struct hid_report_enum *rep_enum; struct hid_report *rep; struct hid_usage *usage; int i, j; rep_enum = &hid->report_enum[HID_FEATURE_REPORT]; list_for_each_entry(rep, &rep_enum->report_list, list) { for (i = 0; i < rep->maxfield; i++) { /* Ignore if report count is out of bounds. */ if (rep->field[i]->report_count < 1) continue; for (j = 0; j < rep->field[i]->maxusage; j++) { usage = &rep->field[i]->usage[j]; if (usage->hid == HID_GD_RESOLUTION_MULTIPLIER) hid_apply_multiplier(hid, rep->field[i]); } } } } EXPORT_SYMBOL_GPL(hid_setup_resolution_multiplier); /** * hid_open_report - open a driver-specific device report * * @device: hid device * * Parse a report description into a hid_device structure. Reports are * enumerated, fields are attached to these reports. * 0 returned on success, otherwise nonzero error value. * * This function (or the equivalent hid_parse() macro) should only be * called from probe() in drivers, before starting the device. */ int hid_open_report(struct hid_device *device) { struct hid_parser *parser; struct hid_item item; unsigned int size; __u8 *start; __u8 *buf; __u8 *end; int ret; static int (*dispatch_type[])(struct hid_parser *parser, struct hid_item *item) = { hid_parser_main, hid_parser_global, hid_parser_local, hid_parser_reserved }; if (WARN_ON(device->status & HID_STAT_PARSED)) return -EBUSY; start = device->dev_rdesc; if (WARN_ON(!start)) return -ENODEV; size = device->dev_rsize; buf = kmemdup(start, size, GFP_KERNEL); if (buf == NULL) return -ENOMEM; if (device->driver->report_fixup) start = device->driver->report_fixup(device, buf, &size); else start = buf; start = kmemdup(start, size, GFP_KERNEL); kfree(buf); if (start == NULL) return -ENOMEM; device->rdesc = start; device->rsize = size; parser = vzalloc(sizeof(struct hid_parser)); if (!parser) { ret = -ENOMEM; goto alloc_err; } parser->device = device; end = start + size; device->collection = kcalloc(HID_DEFAULT_NUM_COLLECTIONS, sizeof(struct hid_collection), GFP_KERNEL); if (!device->collection) { ret = -ENOMEM; goto err; } device->collection_size = HID_DEFAULT_NUM_COLLECTIONS; ret = -EINVAL; while ((start = fetch_item(start, end, &item)) != NULL) { if (item.format != HID_ITEM_FORMAT_SHORT) { hid_err(device, "unexpected long global item\n"); goto err; } if (dispatch_type[item.type](parser, &item)) { hid_err(device, "item %u %u %u %u parsing failed\n", item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag); goto err; } if (start == end) { if (parser->collection_stack_ptr) { hid_err(device, "unbalanced collection at end of report description\n"); goto err; } if (parser->local.delimiter_depth) { hid_err(device, "unbalanced delimiter at end of report description\n"); goto err; } /* * fetch initial values in case the device's * default multiplier isn't the recommended 1 */ hid_setup_resolution_multiplier(device); kfree(parser->collection_stack); vfree(parser); device->status |= HID_STAT_PARSED; return 0; } } hid_err(device, "item fetching failed at offset %d\n", (int)(end - start)); err: kfree(parser->collection_stack); alloc_err: vfree(parser); hid_close_report(device); return ret; } EXPORT_SYMBOL_GPL(hid_open_report); /* * Convert a signed n-bit integer to signed 32-bit integer. Common * cases are done through the compiler, the screwed things has to be * done by hand. */ static s32 snto32(__u32 value, unsigned n) { switch (n) { case 8: return ((__s8)value); case 16: return ((__s16)value); case 32: return ((__s32)value); } return value & (1 << (n - 1)) ? value | (~0U << n) : value; } s32 hid_snto32(__u32 value, unsigned n) { return snto32(value, n); } EXPORT_SYMBOL_GPL(hid_snto32); /* * Convert a signed 32-bit integer to a signed n-bit integer. */ static u32 s32ton(__s32 value, unsigned n) { s32 a = value >> (n - 1); if (a && a != -1) return value < 0 ? 1 << (n - 1) : (1 << (n - 1)) - 1; return value & ((1 << n) - 1); } /* * Extract/implement a data field from/to a little endian report (bit array). * * Code sort-of follows HID spec: * http://www.usb.org/developers/hidpage/HID1_11.pdf * * While the USB HID spec allows unlimited length bit fields in "report * descriptors", most devices never use more than 16 bits. * One model of UPS is claimed to report "LINEV" as a 32-bit field. * Search linux-kernel and linux-usb-devel archives for "hid-core extract". */ static u32 __extract(u8 *report, unsigned offset, int n) { unsigned int idx = offset / 8; unsigned int bit_nr = 0; unsigned int bit_shift = offset % 8; int bits_to_copy = 8 - bit_shift; u32 value = 0; u32 mask = n < 32 ? (1U << n) - 1 : ~0U; while (n > 0) { value |= ((u32)report[idx] >> bit_shift) << bit_nr; n -= bits_to_copy; bit_nr += bits_to_copy; bits_to_copy = 8; bit_shift = 0; idx++; } return value & mask; } u32 hid_field_extract(const struct hid_device *hid, u8 *report, unsigned offset, unsigned n) { if (n > 32) { hid_warn_once(hid, "%s() called with n (%d) > 32! (%s)\n", __func__, n, current->comm); n = 32; } return __extract(report, offset, n); } EXPORT_SYMBOL_GPL(hid_field_extract); /* * "implement" : set bits in a little endian bit stream. * Same concepts as "extract" (see comments above). * The data mangled in the bit stream remains in little endian * order the whole time. It make more sense to talk about * endianness of register values by considering a register * a "cached" copy of the little endian bit stream. */ static void __implement(u8 *report, unsigned offset, int n, u32 value) { unsigned int idx = offset / 8; unsigned int bit_shift = offset % 8; int bits_to_set = 8 - bit_shift; while (n - bits_to_set >= 0) { report[idx] &= ~(0xff << bit_shift); report[idx] |= value << bit_shift; value >>= bits_to_set; n -= bits_to_set; bits_to_set = 8; bit_shift = 0; idx++; } /* last nibble */ if (n) { u8 bit_mask = ((1U << n) - 1); report[idx] &= ~(bit_mask << bit_shift); report[idx] |= value << bit_shift; } } static void implement(const struct hid_device *hid, u8 *report, unsigned offset, unsigned n, u32 value) { if (unlikely(n > 32)) { hid_warn(hid, "%s() called with n (%d) > 32! (%s)\n", __func__, n, current->comm); n = 32; } else if (n < 32) { u32 m = (1U << n) - 1; if (unlikely(value > m)) { hid_warn(hid, "%s() called with too large value %d (n: %d)! (%s)\n", __func__, value, n, current->comm); WARN_ON(1); value &= m; } } __implement(report, offset, n, value); } /* * Search an array for a value. */ static int search(__s32 *array, __s32 value, unsigned n) { while (n--) { if (*array++ == value) return 0; } return -1; } /** * hid_match_report - check if driver's raw_event should be called * * @hid: hid device * @report_type: type to match against * * compare hid->driver->report_table->report_type to report->type */ static int hid_match_report(struct hid_device *hid, struct hid_report *report) { const struct hid_report_id *id = hid->driver->report_table; if (!id) /* NULL means all */ return 1; for (; id->report_type != HID_TERMINATOR; id++) if (id->report_type == HID_ANY_ID || id->report_type == report->type) return 1; return 0; } /** * hid_match_usage - check if driver's event should be called * * @hid: hid device * @usage: usage to match against * * compare hid->driver->usage_table->usage_{type,code} to * usage->usage_{type,code} */ static int hid_match_usage(struct hid_device *hid, struct hid_usage *usage) { const struct hid_usage_id *id = hid->driver->usage_table; if (!id) /* NULL means all */ return 1; for (; id->usage_type != HID_ANY_ID - 1; id++) if ((id->usage_hid == HID_ANY_ID || id->usage_hid == usage->hid) && (id->usage_type == HID_ANY_ID || id->usage_type == usage->type) && (id->usage_code == HID_ANY_ID || id->usage_code == usage->code)) return 1; return 0; } static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, int interrupt) { struct hid_driver *hdrv = hid->driver; int ret; if (!list_empty(&hid->debug_list)) hid_dump_input(hid, usage, value); if (hdrv && hdrv->event && hid_match_usage(hid, usage)) { ret = hdrv->event(hid, field, usage, value); if (ret != 0) { if (ret < 0) hid_err(hid, "%s's event failed with %d\n", hdrv->name, ret); return; } } if (hid->claimed & HID_CLAIMED_INPUT) hidinput_hid_event(hid, field, usage, value); if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt && hid->hiddev_hid_event) hid->hiddev_hid_event(hid, field, usage, value); } /* * Analyse a received field, and fetch the data from it. The field * content is stored for next report processing (we do differential * reporting to the layer). */ static void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, int interrupt) { unsigned n; unsigned count = field->report_count; unsigned offset = field->report_offset; unsigned size = field->report_size; __s32 min = field->logical_minimum; __s32 max = field->logical_maximum; __s32 *value; value = kmalloc_array(count, sizeof(__s32), GFP_ATOMIC); if (!value) return; for (n = 0; n < count; n++) { value[n] = min < 0 ? snto32(hid_field_extract(hid, data, offset + n * size, size), size) : hid_field_extract(hid, data, offset + n * size, size); /* Ignore report if ErrorRollOver */ if (!(field->flags & HID_MAIN_ITEM_VARIABLE) && value[n] >= min && value[n] <= max && value[n] - min < field->maxusage && field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) goto exit; } for (n = 0; n < count; n++) { if (HID_MAIN_ITEM_VARIABLE & field->flags) { hid_process_event(hid, field, &field->usage[n], value[n], interrupt); continue; } if (field->value[n] >= min && field->value[n] <= max && field->value[n] - min < field->maxusage && field->usage[field->value[n] - min].hid && search(value, field->value[n], count)) hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt); if (value[n] >= min && value[n] <= max && value[n] - min < field->maxusage && field->usage[value[n] - min].hid && search(field->value, value[n], count)) hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt); } memcpy(field->value, value, count * sizeof(__s32)); exit: kfree(value); } /* * Output the field into the report. */ static void hid_output_field(const struct hid_device *hid, struct hid_field *field, __u8 *data) { unsigned count = field->report_count; unsigned offset = field->report_offset; unsigned size = field->report_size; unsigned n; for (n = 0; n < count; n++) { if (field->logical_minimum < 0) /* signed values */ implement(hid, data, offset + n * size, size, s32ton(field->value[n], size)); else /* unsigned values */ implement(hid, data, offset + n * size, size, field->value[n]); } } /* * Create a report. 'data' has to be allocated using * hid_alloc_report_buf() so that it has proper size. */ void hid_output_report(struct hid_report *report, __u8 *data) { unsigned n; if (report->id > 0) *data++ = report->id; memset(data, 0, ((report->size - 1) >> 3) + 1); for (n = 0; n < report->maxfield; n++) hid_output_field(report->device, report->field[n], data); } EXPORT_SYMBOL_GPL(hid_output_report); /* * Allocator for buffer that is going to be passed to hid_output_report() */ u8 *hid_alloc_report_buf(struct hid_report *report, gfp_t flags) { /* * 7 extra bytes are necessary to achieve proper functionality * of implement() working on 8 byte chunks */ u32 len = hid_report_len(report) + 7; return kmalloc(len, flags); } EXPORT_SYMBOL_GPL(hid_alloc_report_buf); /* * Set a field value. The report this field belongs to has to be * created and transferred to the device, to set this value in the * device. */ int hid_set_field(struct hid_field *field, unsigned offset, __s32 value) { unsigned size; if (!field) return -1; size = field->report_size; hid_dump_input(field->report->device, field->usage + offset, value); if (offset >= field->report_count) { hid_err(field->report->device, "offset (%d) exceeds report_count (%d)\n", offset, field->report_count); return -1; } if (field->logical_minimum < 0) { if (value != snto32(s32ton(value, size), size)) { hid_err(field->report->device, "value %d is out of range\n", value); return -1; } } field->value[offset] = value; return 0; } EXPORT_SYMBOL_GPL(hid_set_field); static struct hid_report *hid_get_report(struct hid_report_enum *report_enum, const u8 *data) { struct hid_report *report; unsigned int n = 0; /* Normally report number is 0 */ /* Device uses numbered reports, data[0] is report number */ if (report_enum->numbered) n = *data; report = report_enum->report_id_hash[n]; if (report == NULL) dbg_hid("undefined report_id %u received\n", n); return report; } /* * Implement a generic .request() callback, using .raw_request() * DO NOT USE in hid drivers directly, but through hid_hw_request instead. */ int __hid_request(struct hid_device *hid, struct hid_report *report, int reqtype) { char *buf; int ret; u32 len; buf = hid_alloc_report_buf(report, GFP_KERNEL); if (!buf) return -ENOMEM; len = hid_report_len(report); if (reqtype == HID_REQ_SET_REPORT) hid_output_report(report, buf); ret = hid->ll_driver->raw_request(hid, report->id, buf, len, report->type, reqtype); if (ret < 0) { dbg_hid("unable to complete request: %d\n", ret); goto out; } if (reqtype == HID_REQ_GET_REPORT) hid_input_report(hid, report->type, buf, ret, 0); ret = 0; out: kfree(buf); return ret; } EXPORT_SYMBOL_GPL(__hid_request); int hid_report_raw_event(struct hid_device *hid, int type, u8 *data, u32 size, int interrupt) { struct hid_report_enum *report_enum = hid->report_enum + type; struct hid_report *report; struct hid_driver *hdrv; unsigned int a; u32 rsize, csize = size; u8 *cdata = data; int ret = 0; report = hid_get_report(report_enum, data); if (!report) goto out; if (report_enum->numbered) { cdata++; csize--; } rsize = ((report->size - 1) >> 3) + 1; if (rsize > HID_MAX_BUFFER_SIZE) rsize = HID_MAX_BUFFER_SIZE; if (csize < rsize) { dbg_hid("report %d is too short, (%d < %d)\n", report->id, csize, rsize); memset(cdata + csize, 0, rsize - csize); } if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_report_event) hid->hiddev_report_event(hid, report); if (hid->claimed & HID_CLAIMED_HIDRAW) { ret = hidraw_report_event(hid, data, size); if (ret) goto out; } if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) { for (a = 0; a < report->maxfield; a++) hid_input_field(hid, report->field[a], cdata, interrupt); hdrv = hid->driver; if (hdrv && hdrv->report) hdrv->report(hid, report); } if (hid->claimed & HID_CLAIMED_INPUT) hidinput_report_event(hid, report); out: return ret; } EXPORT_SYMBOL_GPL(hid_report_raw_event); /** * hid_input_report - report data from lower layer (usb, bt...) * * @hid: hid device * @type: HID report type (HID_*_REPORT) * @data: report contents * @size: size of data parameter * @interrupt: distinguish between interrupt and control transfers * * This is data entry for lower layers. */ int hid_input_report(struct hid_device *hid, int type, u8 *data, u32 size, int interrupt) { struct hid_report_enum *report_enum; struct hid_driver *hdrv; struct hid_report *report; int ret = 0; if (!hid) return -ENODEV; if (down_trylock(&hid->driver_input_lock)) return -EBUSY; if (!hid->driver) { ret = -ENODEV; goto unlock; } report_enum = hid->report_enum + type; hdrv = hid->driver; if (!size) { dbg_hid("empty report\n"); ret = -1; goto unlock; } /* Avoid unnecessary overhead if debugfs is disabled */ if (!list_empty(&hid->debug_list)) hid_dump_report(hid, type, data, size); report = hid_get_report(report_enum, data); if (!report) { ret = -1; goto unlock; } if (hdrv && hdrv->raw_event && hid_match_report(hid, report)) { ret = hdrv->raw_event(hid, report, data, size); if (ret < 0) goto unlock; } ret = hid_report_raw_event(hid, type, data, size, interrupt); unlock: up(&hid->driver_input_lock); return ret; } EXPORT_SYMBOL_GPL(hid_input_report); bool hid_match_one_id(const struct hid_device *hdev, const struct hid_device_id *id) { return (id->bus == HID_BUS_ANY || id->bus == hdev->bus) && (id->group == HID_GROUP_ANY || id->group == hdev->group) && (id->vendor == HID_ANY_ID || id->vendor == hdev->vendor) && (id->product == HID_ANY_ID || id->product == hdev->product); } const struct hid_device_id *hid_match_id(const struct hid_device *hdev, const struct hid_device_id *id) { for (; id->bus; id++) if (hid_match_one_id(hdev, id)) return id; return NULL; } static const struct hid_device_id hid_hiddev_list[] = { { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS) }, { HID_USB_DEVICE(USB_VENDOR_ID_MGE, USB_DEVICE_ID_MGE_UPS1) }, { } }; static bool hid_hiddev(struct hid_device *hdev) { return !!hid_match_id(hdev, hid_hiddev_list); } static ssize_t read_report_descriptor(struct file *filp, struct kobject *kobj, struct bin_attribute *attr, char *buf, loff_t off, size_t count) { struct device *dev = kobj_to_dev(kobj); struct hid_device *hdev = to_hid_device(dev); if (off >= hdev->rsize) return 0; if (off + count > hdev->rsize) count = hdev->rsize - off; memcpy(buf, hdev->rdesc + off, count); return count; } static ssize_t show_country(struct device *dev, struct device_attribute *attr, char *buf) { struct hid_device *hdev = to_hid_device(dev); return sprintf(buf, "%02x\n", hdev->country & 0xff); } static struct bin_attribute dev_bin_attr_report_desc = { .attr = { .name = "report_descriptor", .mode = 0444 }, .read = read_report_descriptor, .size = HID_MAX_DESCRIPTOR_SIZE, }; static const struct device_attribute dev_attr_country = { .attr = { .name = "country", .mode = 0444 }, .show = show_country, }; int hid_connect(struct hid_device *hdev, unsigned int connect_mask) { static const char *types[] = { "Device", "Pointer", "Mouse", "Device", "Joystick", "Gamepad", "Keyboard", "Keypad", "Multi-Axis Controller" }; const char *type, *bus; char buf[64] = ""; unsigned int i; int len; int ret; if (hdev->quirks & HID_QUIRK_HIDDEV_FORCE) connect_mask |= (HID_CONNECT_HIDDEV_FORCE | HID_CONNECT_HIDDEV); if (hdev->quirks & HID_QUIRK_HIDINPUT_FORCE) connect_mask |= HID_CONNECT_HIDINPUT_FORCE; if (hdev->bus != BUS_USB) connect_mask &= ~HID_CONNECT_HIDDEV; if (hid_hiddev(hdev)) connect_mask |= HID_CONNECT_HIDDEV_FORCE; if ((connect_mask & HID_CONNECT_HIDINPUT) && !hidinput_connect(hdev, connect_mask & HID_CONNECT_HIDINPUT_FORCE)) hdev->claimed |= HID_CLAIMED_INPUT; if ((connect_mask & HID_CONNECT_HIDDEV) && hdev->hiddev_connect && !hdev->hiddev_connect(hdev, connect_mask & HID_CONNECT_HIDDEV_FORCE)) hdev->claimed |= HID_CLAIMED_HIDDEV; if ((connect_mask & HID_CONNECT_HIDRAW) && !hidraw_connect(hdev)) hdev->claimed |= HID_CLAIMED_HIDRAW; if (connect_mask & HID_CONNECT_DRIVER) hdev->claimed |= HID_CLAIMED_DRIVER; /* Drivers with the ->raw_event callback set are not required to connect * to any other listener. */ if (!hdev->claimed && !hdev->driver->raw_event) { hid_err(hdev, "device has no listeners, quitting\n"); return -ENODEV; } if ((hdev->claimed & HID_CLAIMED_INPUT) && (connect_mask & HID_CONNECT_FF) && hdev->ff_init) hdev->ff_init(hdev); len = 0; if (hdev->claimed & HID_CLAIMED_INPUT) len += sprintf(buf + len, "input"); if (hdev->claimed & HID_CLAIMED_HIDDEV) len += sprintf(buf + len, "%shiddev%d", len ? "," : "", ((struct hiddev *)hdev->hiddev)->minor); if (hdev->claimed & HID_CLAIMED_HIDRAW) len += sprintf(buf + len, "%shidraw%d", len ? "," : "", ((struct hidraw *)hdev->hidraw)->minor); type = "Device"; for (i = 0; i < hdev->maxcollection; i++) { struct hid_collection *col = &hdev->collection[i]; if (col->type == HID_COLLECTION_APPLICATION && (col->usage & HID_USAGE_PAGE) == HID_UP_GENDESK && (col->usage & 0xffff) < ARRAY_SIZE(types)) { type = types[col->usage & 0xffff]; break; } } switch (hdev->bus) { case BUS_USB: bus = "USB"; break; case BUS_BLUETOOTH: bus = "BLUETOOTH"; break; case BUS_I2C: bus = "I2C"; break; default: bus = ""; } ret = device_create_file(&hdev->dev, &dev_attr_country); if (ret) hid_warn(hdev, "can't create sysfs country code attribute err: %d\n", ret); hid_info(hdev, "%s: %s HID v%x.%02x %s [%s] on %s\n", buf, bus, hdev->version >> 8, hdev->version & 0xff, type, hdev->name, hdev->phys); return 0; } EXPORT_SYMBOL_GPL(hid_connect); void hid_disconnect(struct hid_device *hdev) { device_remove_file(&hdev->dev, &dev_attr_country); if (hdev->claimed & HID_CLAIMED_INPUT) hidinput_disconnect(hdev); if (hdev->claimed & HID_CLAIMED_HIDDEV) hdev->hiddev_disconnect(hdev); if (hdev->claimed & HID_CLAIMED_HIDRAW) hidraw_disconnect(hdev); hdev->claimed = 0; } EXPORT_SYMBOL_GPL(hid_disconnect); /** * hid_hw_start - start underlying HW * @hdev: hid device * @connect_mask: which outputs to connect, see HID_CONNECT_* * * Call this in probe function *after* hid_parse. This will setup HW * buffers and start the device (if not defeirred to device open). * hid_hw_stop must be called if this was successful. */ int hid_hw_start(struct hid_device *hdev, unsigned int connect_mask) { int error; error = hdev->ll_driver->start(hdev); if (error) return error; if (connect_mask) { error = hid_connect(hdev, connect_mask); if (error) { hdev->ll_driver->stop(hdev); return error; } } return 0; } EXPORT_SYMBOL_GPL(hid_hw_start); /** * hid_hw_stop - stop underlying HW * @hdev: hid device * * This is usually called from remove function or from probe when something * failed and hid_hw_start was called already. */ void hid_hw_stop(struct hid_device *hdev) { hid_disconnect(hdev); hdev->ll_driver->stop(hdev); } EXPORT_SYMBOL_GPL(hid_hw_stop); /** * hid_hw_open - signal underlying HW to start delivering events * @hdev: hid device * * Tell underlying HW to start delivering events from the device. * This function should be called sometime after successful call * to hid_hw_start(). */ int hid_hw_open(struct hid_device *hdev) { int ret; ret = mutex_lock_killable(&hdev->ll_open_lock); if (ret) return ret; if (!hdev->ll_open_count++) { ret = hdev->ll_driver->open(hdev); if (ret) hdev->ll_open_count--; } mutex_unlock(&hdev->ll_open_lock); return ret; } EXPORT_SYMBOL_GPL(hid_hw_open); /** * hid_hw_close - signal underlaying HW to stop delivering events * * @hdev: hid device * * This function indicates that we are not interested in the events * from this device anymore. Delivery of events may or may not stop, * depending on the number of users still outstanding. */ void hid_hw_close(struct hid_device *hdev) { mutex_lock(&hdev->ll_open_lock); if (!--hdev->ll_open_count) hdev->ll_driver->close(hdev); mutex_unlock(&hdev->ll_open_lock); } EXPORT_SYMBOL_GPL(hid_hw_close); struct hid_dynid { struct list_head list; struct hid_device_id id; }; /** * store_new_id - add a new HID device ID to this driver and re-probe devices * @driver: target device driver * @buf: buffer for scanning device ID data * @count: input size * * Adds a new dynamic hid device ID to this driver, * and causes the driver to probe for all devices again. */ static ssize_t new_id_store(struct device_driver *drv, const char *buf, size_t count) { struct hid_driver *hdrv = to_hid_driver(drv); struct hid_dynid *dynid; __u32 bus, vendor, product; unsigned long driver_data = 0; int ret; ret = sscanf(buf, "%x %x %x %lx", &bus, &vendor, &product, &driver_data); if (ret < 3) return -EINVAL; dynid = kzalloc(sizeof(*dynid), GFP_KERNEL); if (!dynid) return -ENOMEM; dynid->id.bus = bus; dynid->id.group = HID_GROUP_ANY; dynid->id.vendor = vendor; dynid->id.product = product; dynid->id.driver_data = driver_data; spin_lock(&hdrv->dyn_lock); list_add_tail(&dynid->list, &hdrv->dyn_list); spin_unlock(&hdrv->dyn_lock); ret = driver_attach(&hdrv->driver); return ret ? : count; } static DRIVER_ATTR_WO(new_id); static struct attribute *hid_drv_attrs[] = { &driver_attr_new_id.attr, NULL, }; ATTRIBUTE_GROUPS(hid_drv); static void hid_free_dynids(struct hid_driver *hdrv) { struct hid_dynid *dynid, *n; spin_lock(&hdrv->dyn_lock); list_for_each_entry_safe(dynid, n, &hdrv->dyn_list, list) { list_del(&dynid->list); kfree(dynid); } spin_unlock(&hdrv->dyn_lock); } const struct hid_device_id *hid_match_device(struct hid_device *hdev, struct hid_driver *hdrv) { struct hid_dynid *dynid; spin_lock(&hdrv->dyn_lock); list_for_each_entry(dynid, &hdrv->dyn_list, list) { if (hid_match_one_id(hdev, &dynid->id)) { spin_unlock(&hdrv->dyn_lock); return &dynid->id; } } spin_unlock(&hdrv->dyn_lock); return hid_match_id(hdev, hdrv->id_table); } EXPORT_SYMBOL_GPL(hid_match_device); static int hid_bus_match(struct device *dev, struct device_driver *drv) { struct hid_driver *hdrv = to_hid_driver(drv); struct hid_device *hdev = to_hid_device(dev); return hid_match_device(hdev, hdrv) != NULL; } /** * hid_compare_device_paths - check if both devices share the same path * @hdev_a: hid device * @hdev_b: hid device * @separator: char to use as separator * * Check if two devices share the same path up to the last occurrence of * the separator char. Both paths must exist (i.e., zero-length paths * don't match). */ bool hid_compare_device_paths(struct hid_device *hdev_a, struct hid_device *hdev_b, char separator) { int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys; int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys; if (n1 != n2 || n1 <= 0 || n2 <= 0) return false; return !strncmp(hdev_a->phys, hdev_b->phys, n1); } EXPORT_SYMBOL_GPL(hid_compare_device_paths); static int hid_device_probe(struct device *dev) { struct hid_driver *hdrv = to_hid_driver(dev->driver); struct hid_device *hdev = to_hid_device(dev); const struct hid_device_id *id; int ret = 0; if (down_interruptible(&hdev->driver_input_lock)) { ret = -EINTR; goto end; } hdev->io_started = false; clear_bit(ffs(HID_STAT_REPROBED), &hdev->status); if (!hdev->driver) { id = hid_match_device(hdev, hdrv); if (id == NULL) { ret = -ENODEV; goto unlock; } if (hdrv->match) { if (!hdrv->match(hdev, hid_ignore_special_drivers)) { ret = -ENODEV; goto unlock; } } else { /* * hid-generic implements .match(), so if * hid_ignore_special_drivers is set, we can safely * return. */ if (hid_ignore_special_drivers) { ret = -ENODEV; goto unlock; } } /* reset the quirks that has been previously set */ hdev->quirks = hid_lookup_quirk(hdev); hdev->driver = hdrv; if (hdrv->probe) { ret = hdrv->probe(hdev, id); } else { /* default probe */ ret = hid_open_report(hdev); if (!ret) ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); } if (ret) { hid_close_report(hdev); hdev->driver = NULL; } } unlock: if (!hdev->io_started) up(&hdev->driver_input_lock); end: return ret; } static int hid_device_remove(struct device *dev) { struct hid_device *hdev = to_hid_device(dev); struct hid_driver *hdrv; int ret = 0; if (down_interruptible(&hdev->driver_input_lock)) { ret = -EINTR; goto end; } hdev->io_started = false; hdrv = hdev->driver; if (hdrv) { if (hdrv->remove) hdrv->remove(hdev); else /* default remove */ hid_hw_stop(hdev); hid_close_report(hdev); hdev->driver = NULL; } if (!hdev->io_started) up(&hdev->driver_input_lock); end: return ret; } static ssize_t modalias_show(struct device *dev, struct device_attribute *a, char *buf) { struct hid_device *hdev = container_of(dev, struct hid_device, dev); return scnprintf(buf, PAGE_SIZE, "hid:b%04Xg%04Xv%08Xp%08X\n", hdev->bus, hdev->group, hdev->vendor, hdev->product); } static DEVICE_ATTR_RO(modalias); static struct attribute *hid_dev_attrs[] = { &dev_attr_modalias.attr, NULL, }; static struct bin_attribute *hid_dev_bin_attrs[] = { &dev_bin_attr_report_desc, NULL }; static const struct attribute_group hid_dev_group = { .attrs = hid_dev_attrs, .bin_attrs = hid_dev_bin_attrs, }; __ATTRIBUTE_GROUPS(hid_dev); static int hid_uevent(struct device *dev, struct kobj_uevent_env *env) { struct hid_device *hdev = to_hid_device(dev); if (add_uevent_var(env, "HID_ID=%04X:%08X:%08X", hdev->bus, hdev->vendor, hdev->product)) return -ENOMEM; if (add_uevent_var(env, "HID_NAME=%s", hdev->name)) return -ENOMEM; if (add_uevent_var(env, "HID_PHYS=%s", hdev->phys)) return -ENOMEM; if (add_uevent_var(env, "HID_UNIQ=%s", hdev->uniq)) return -ENOMEM; if (add_uevent_var(env, "MODALIAS=hid:b%04Xg%04Xv%08Xp%08X", hdev->bus, hdev->group, hdev->vendor, hdev->product)) return -ENOMEM; return 0; } struct bus_type hid_bus_type = { .name = "hid", .dev_groups = hid_dev_groups, .drv_groups = hid_drv_groups, .match = hid_bus_match, .probe = hid_device_probe, .remove = hid_device_remove, .uevent = hid_uevent, }; EXPORT_SYMBOL(hid_bus_type); int hid_add_device(struct hid_device *hdev) { static atomic_t id = ATOMIC_INIT(0); int ret; if (WARN_ON(hdev->status & HID_STAT_ADDED)) return -EBUSY; hdev->quirks = hid_lookup_quirk(hdev); /* we need to kill them here, otherwise they will stay allocated to * wait for coming driver */ if (hid_ignore(hdev)) return -ENODEV; /* * Check for the mandatory transport channel. */ if (!hdev->ll_driver->raw_request) { hid_err(hdev, "transport driver missing .raw_request()\n"); return -EINVAL; } /* * Read the device report descriptor once and use as template * for the driver-specific modifications. */ ret = hdev->ll_driver->parse(hdev); if (ret) return ret; if (!hdev->dev_rdesc) return -ENODEV; /* * Scan generic devices for group information */ if (hid_ignore_special_drivers) { hdev->group = HID_GROUP_GENERIC; } else if (!hdev->group && !(hdev->quirks & HID_QUIRK_HAVE_SPECIAL_DRIVER)) { ret = hid_scan_report(hdev); if (ret) hid_warn(hdev, "bad device descriptor (%d)\n", ret); } /* XXX hack, any other cleaner solution after the driver core * is converted to allow more than 20 bytes as the device name? */ dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus, hdev->vendor, hdev->product, atomic_inc_return(&id)); hid_debug_register(hdev, dev_name(&hdev->dev)); ret = device_add(&hdev->dev); if (!ret) hdev->status |= HID_STAT_ADDED; else hid_debug_unregister(hdev); return ret; } EXPORT_SYMBOL_GPL(hid_add_device); /** * hid_allocate_device - allocate new hid device descriptor * * Allocate and initialize hid device, so that hid_destroy_device might be * used to free it. * * New hid_device pointer is returned on success, otherwise ERR_PTR encoded * error value. */ struct hid_device *hid_allocate_device(void) { struct hid_device *hdev; int ret = -ENOMEM; hdev = kzalloc(sizeof(*hdev), GFP_KERNEL); if (hdev == NULL) return ERR_PTR(ret); device_initialize(&hdev->dev); hdev->dev.release = hid_device_release; hdev->dev.bus = &hid_bus_type; device_enable_async_suspend(&hdev->dev); hid_close_report(hdev); init_waitqueue_head(&hdev->debug_wait); INIT_LIST_HEAD(&hdev->debug_list); spin_lock_init(&hdev->debug_list_lock); sema_init(&hdev->driver_input_lock, 1); mutex_init(&hdev->ll_open_lock); return hdev; } EXPORT_SYMBOL_GPL(hid_allocate_device); static void hid_remove_device(struct hid_device *hdev) { if (hdev->status & HID_STAT_ADDED) { device_del(&hdev->dev); hid_debug_unregister(hdev); hdev->status &= ~HID_STAT_ADDED; } kfree(hdev->dev_rdesc); hdev->dev_rdesc = NULL; hdev->dev_rsize = 0; } /** * hid_destroy_device - free previously allocated device * * @hdev: hid device * * If you allocate hid_device through hid_allocate_device, you should ever * free by this function. */ void hid_destroy_device(struct hid_device *hdev) { hid_remove_device(hdev); put_device(&hdev->dev); } EXPORT_SYMBOL_GPL(hid_destroy_device); static int __hid_bus_reprobe_drivers(struct device *dev, void *data) { struct hid_driver *hdrv = data; struct hid_device *hdev = to_hid_device(dev); if (hdev->driver == hdrv && !hdrv->match(hdev, hid_ignore_special_drivers) && !test_and_set_bit(ffs(HID_STAT_REPROBED), &hdev->status)) return device_reprobe(dev); return 0; } static int __hid_bus_driver_added(struct device_driver *drv, void *data) { struct hid_driver *hdrv = to_hid_driver(drv); if (hdrv->match) { bus_for_each_dev(&hid_bus_type, NULL, hdrv, __hid_bus_reprobe_drivers); } return 0; } static int __bus_removed_driver(struct device_driver *drv, void *data) { return bus_rescan_devices(&hid_bus_type); } int __hid_register_driver(struct hid_driver *hdrv, struct module *owner, const char *mod_name) { int ret; hdrv->driver.name = hdrv->name; hdrv->driver.bus = &hid_bus_type; hdrv->driver.owner = owner; hdrv->driver.mod_name = mod_name; INIT_LIST_HEAD(&hdrv->dyn_list); spin_lock_init(&hdrv->dyn_lock); ret = driver_register(&hdrv->driver); if (ret == 0) bus_for_each_drv(&hid_bus_type, NULL, NULL, __hid_bus_driver_added); return ret; } EXPORT_SYMBOL_GPL(__hid_register_driver); void hid_unregister_driver(struct hid_driver *hdrv) { driver_unregister(&hdrv->driver); hid_free_dynids(hdrv); bus_for_each_drv(&hid_bus_type, NULL, hdrv, __bus_removed_driver); } EXPORT_SYMBOL_GPL(hid_unregister_driver); int hid_check_keys_pressed(struct hid_device *hid) { struct hid_input *hidinput; int i; if (!(hid->claimed & HID_CLAIMED_INPUT)) return 0; list_for_each_entry(hidinput, &hid->inputs, list) { for (i = 0; i < BITS_TO_LONGS(KEY_MAX); i++) if (hidinput->input->key[i]) return 1; } return 0; } EXPORT_SYMBOL_GPL(hid_check_keys_pressed); static int __init hid_init(void) { int ret; if (hid_debug) pr_warn("hid_debug is now used solely for parser and driver debugging.\n" "debugfs is now used for inspecting the device (report descriptor, reports)\n"); ret = bus_register(&hid_bus_type); if (ret) { pr_err("can't register hid bus\n"); goto err; } ret = hidraw_init(); if (ret) goto err_bus; hid_debug_init(); return 0; err_bus: bus_unregister(&hid_bus_type); err: return ret; } static void __exit hid_exit(void) { hid_debug_exit(); hidraw_exit(); bus_unregister(&hid_bus_type); hid_quirks_exit(HID_BUS_ANY); } module_init(hid_init); module_exit(hid_exit); MODULE_AUTHOR("Andreas Gal"); MODULE_AUTHOR("Vojtech Pavlik"); MODULE_AUTHOR("Jiri Kosina"); MODULE_LICENSE("GPL");