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linux/drivers/hid/hid-core.c
Jiri Kosina 903796855b Merge branch 'for-6.13/bpf' into for-linus 
- improvement of the way hid-bpf coexists with specific drivers (others than
  hid-generic) that are already bound to devices (Benjamin Tissoires)
2024-11-18 22:02:17 +01:00

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* HID support for Linux
*
* Copyright (c) 1999 Andreas Gal
* Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
* Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
* Copyright (c) 2006-2012 Jiri Kosina
*/
/*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/spinlock.h>
#include <linux/unaligned.h>
#include <asm/byteorder.h>
#include <linux/input.h>
#include <linux/wait.h>
#include <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/semaphore.h>
#include <linux/hid.h>
#include <linux/hiddev.h>
#include <linux/hid-debug.h>
#include <linux/hidraw.h>
#include "hid-ids.h"
/*
* Version Information
*/
#define DRIVER_DESC "HID core driver"
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");
/*
* Convert a signed n-bit integer to signed 32-bit integer.
*/
static s32 snto32(__u32 value, unsigned int n)
{
if (!value || !n)
return 0;
if (n > 32)
n = 32;
return sign_extend32(value, n - 1);
}
/*
* Convert a signed 32-bit integer to a signed n-bit integer.
*/
static u32 s32ton(__s32 value, unsigned int 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);
}
/*
* Register a new report for a device.
*/
struct hid_report *hid_register_report(struct hid_device *device,
enum hid_report_type 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);
INIT_LIST_HEAD(&report->field_entry_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)
{
struct hid_field *field;
if (report->maxfield == HID_MAX_FIELDS) {
hid_err(report->device, "too many fields in report\n");
return NULL;
}
field = kvzalloc((sizeof(struct hid_field) +
usages * sizeof(struct hid_usage) +
3 * usages * sizeof(unsigned int)), 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->new_value = (s32 *)(field->value + usages);
field->usages_priorities = (s32 *)(field->new_value + 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 */
}
/*
* Concatenate usage which defines 16 bits or less with the
* currently defined usage page to form a 32 bit usage
*/
static void complete_usage(struct hid_parser *parser, unsigned int index)
{
parser->local.usage[index] &= 0xFFFF;
parser->local.usage[index] |=
(parser->global.usage_page & 0xFFFF) << 16;
}
/*
* 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;
/*
* If Usage item only includes usage id, concatenate it with
* currently defined usage page
*/
if (size <= 2)
complete_usage(parser, parser->local.usage_index);
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 max_buffer_size = HID_MAX_BUFFER_SIZE;
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->device->ll_driver->max_buffer_size)
max_buffer_size = parser->device->ll_driver->max_buffer_size;
/* Total size check: Allow for possible report index byte */
if (report->size > (max_buffer_size - 1) << 3) {
hid_err(parser->device, "report is too long\n");
return -1;
}
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);
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 = 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_last_usage_page(struct hid_parser *parser)
{
int i;
unsigned int usage_page;
unsigned int current_page;
if (!parser->local.usage_index)
return;
usage_page = parser->global.usage_page;
/*
* Concatenate usage page again only if last declared Usage Page
* has not been already used in previous usages concatenation
*/
for (i = parser->local.usage_index - 1; i >= 0; i--) {
if (parser->local.usage_size[i] > 2)
/* Ignore extended usages */
continue;
current_page = parser->local.usage[i] >> 16;
if (current_page == usage_page)
break;
complete_usage(parser, i);
}
}
/*
* Process a main item.
*/
static int hid_parser_main(struct hid_parser *parser, struct hid_item *item)
{
__u32 data;
int ret;
hid_concatenate_last_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;
kfree(report->field_entries);
for (n = 0; n < report->maxfield; n++)
kvfree(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);
}
/*
* If the HID driver had a rdesc_fixup() callback, dev->rdesc
* will be allocated by hid-core and needs to be freed.
* Otherwise, it is either equal to dev_rdesc or bpf_rdesc, in
* which cases it'll be freed later on device removal or destroy.
*/
if (device->rdesc != device->dev_rdesc && device->rdesc != device->bpf_rdesc)
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;
}
static inline void hid_free_bpf_rdesc(struct hid_device *hdev)
{
/* bpf_rdesc is either equal to dev_rdesc or allocated by call_hid_bpf_rdesc_fixup() */
if (hdev->bpf_rdesc != hdev->dev_rdesc)
kfree(hdev->bpf_rdesc);
hdev->bpf_rdesc = NULL;
}
/*
* Free a device structure, all reports, and all fields.
*/
void hiddev_free(struct kref *ref)
{
struct hid_device *hid = container_of(ref, struct hid_device, ref);
hid_close_report(hid);
hid_free_bpf_rdesc(hid);
kfree(hid->dev_rdesc);
kfree(hid);
}
static void hid_device_release(struct device *dev)
{
struct hid_device *hid = to_hid_device(dev);
kref_put(&hid->ref, hiddev_free);
}
/*
* Fetch a report description item from the data stream. We support long
* items, though they are not used yet.
*/
static const u8 *fetch_item(const __u8 *start, const __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 = BIT(b & 3) >> 1; /* 0, 1, 2, 3 -> 0, 1, 2, 4 */
if (end - start < item->size)
return NULL;
switch (item->size) {
case 0:
break;
case 1:
item->data.u8 = *start;
break;
case 2:
item->data.u16 = get_unaligned_le16(start);
break;
case 4:
item->data.u32 = get_unaligned_le32(start);
break;
}
return start + item->size;
}
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;
if (usage == 0xff0000c6 && parser->global.report_count == 1 &&
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 ||
type == HID_COLLECTION_APPLICATION))
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;
if ((parser->global.usage_page << 16) == HID_UP_GOOGLEVENDOR)
for (i = 0; i < parser->local.usage_index; i++)
if (parser->local.usage[i] ==
(HID_UP_GOOGLEVENDOR | 0x0001))
parser->device->group =
HID_GROUP_VIVALDI;
}
static int hid_scan_main(struct hid_parser *parser, struct hid_item *item)
{
__u32 data;
int i;
hid_concatenate_last_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;
const __u8 *start = hid->dev_rdesc;
const __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
*
* @hid: 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, const __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
*
* @hid: 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,
enum hid_report_type 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_first_entry_or_null(
&hid->report_enum[type].report_list,
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;
const __u8 *start;
const __u8 *end;
const __u8 *next;
int ret;
int i;
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->bpf_rdesc;
if (WARN_ON(!start))
return -ENODEV;
size = device->bpf_rsize;
if (device->driver->report_fixup) {
/*
* device->driver->report_fixup() needs to work
* on a copy of our report descriptor so it can
* change it.
*/
__u8 *buf = kmemdup(start, size, GFP_KERNEL);
if (buf == NULL)
return -ENOMEM;
start = device->driver->report_fixup(device, buf, &size);
/*
* The second kmemdup is required in case report_fixup() returns
* a static read-only memory, but we have no idea if that memory
* needs to be cleaned up or not at the end.
*/
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;
for (i = 0; i < HID_DEFAULT_NUM_COLLECTIONS; i++)
device->collection[i].parent_idx = -1;
ret = -EINVAL;
while ((next = fetch_item(start, end, &item)) != NULL) {
start = next;
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 %u/%u\n",
size - (unsigned int)(end - start), size);
err:
kfree(parser->collection_stack);
alloc_err:
vfree(parser);
hid_close_report(device);
return ret;
}
EXPORT_SYMBOL_GPL(hid_open_report);
/*
* 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);
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: hid report 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);
}
/*
* Checks if the given value is valid within this field
*/
static inline int hid_array_value_is_valid(struct hid_field *field,
__s32 value)
{
__s32 min = field->logical_minimum;
/*
* Value needs to be between logical min and max, and
* (value - min) is used as an index in the usage array.
* This array is of size field->maxusage
*/
return value >= min &&
value <= field->logical_maximum &&
value - min < field->maxusage;
}
/*
* Fetch the field from the data. The field content is stored for next
* report processing (we do differential reporting to the layer).
*/
static void hid_input_fetch_field(struct hid_device *hid,
struct hid_field *field,
__u8 *data)
{
unsigned n;
unsigned count = field->report_count;
unsigned offset = field->report_offset;
unsigned size = field->report_size;
__s32 min = field->logical_minimum;
__s32 *value;
value = field->new_value;
memset(value, 0, count * sizeof(__s32));
field->ignored = false;
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) &&
hid_array_value_is_valid(field, value[n]) &&
field->usage[value[n] - min].hid == HID_UP_KEYBOARD + 1) {
field->ignored = true;
return;
}
}
}
/*
* Process a received variable field.
*/
static void hid_input_var_field(struct hid_device *hid,
struct hid_field *field,
int interrupt)
{
unsigned int count = field->report_count;
__s32 *value = field->new_value;
unsigned int n;
for (n = 0; n < count; n++)
hid_process_event(hid,
field,
&field->usage[n],
value[n],
interrupt);
memcpy(field->value, value, count * sizeof(__s32));
}
/*
* Process a received array field. The field content is stored for
* next report processing (we do differential reporting to the layer).
*/
static void hid_input_array_field(struct hid_device *hid,
struct hid_field *field,
int interrupt)
{
unsigned int n;
unsigned int count = field->report_count;
__s32 min = field->logical_minimum;
__s32 *value;
value = field->new_value;
/* ErrorRollOver */
if (field->ignored)
return;
for (n = 0; n < count; n++) {
if (hid_array_value_is_valid(field, field->value[n]) &&
search(value, field->value[n], count))
hid_process_event(hid,
field,
&field->usage[field->value[n] - min],
0,
interrupt);
if (hid_array_value_is_valid(field, value[n]) &&
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));
}
/*
* Analyse a received report, 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_process_report(struct hid_device *hid,
struct hid_report *report,
__u8 *data,
int interrupt)
{
unsigned int a;
struct hid_field_entry *entry;
struct hid_field *field;
/* first retrieve all incoming values in data */
for (a = 0; a < report->maxfield; a++)
hid_input_fetch_field(hid, report->field[a], data);
if (!list_empty(&report->field_entry_list)) {
/* INPUT_REPORT, we have a priority list of fields */
list_for_each_entry(entry,
&report->field_entry_list,
list) {
field = entry->field;
if (field->flags & HID_MAIN_ITEM_VARIABLE)
hid_process_event(hid,
field,
&field->usage[entry->index],
field->new_value[entry->index],
interrupt);
else
hid_input_array_field(hid, field, interrupt);
}
/* we need to do the memcpy at the end for var items */
for (a = 0; a < report->maxfield; a++) {
field = report->field[a];
if (field->flags & HID_MAIN_ITEM_VARIABLE)
memcpy(field->value, field->new_value,
field->report_count * sizeof(__s32));
}
} else {
/* FEATURE_REPORT, regular processing */
for (a = 0; a < report->maxfield; a++) {
field = report->field[a];
if (field->flags & HID_MAIN_ITEM_VARIABLE)
hid_input_var_field(hid, field, interrupt);
else
hid_input_array_field(hid, field, interrupt);
}
}
}
/*
* Insert a given usage_index in a field in the list
* of processed usages in the report.
*
* The elements of lower priority score are processed
* first.
*/
static void __hid_insert_field_entry(struct hid_device *hid,
struct hid_report *report,
struct hid_field_entry *entry,
struct hid_field *field,
unsigned int usage_index)
{
struct hid_field_entry *next;
entry->field = field;
entry->index = usage_index;
entry->priority = field->usages_priorities[usage_index];
/* insert the element at the correct position */
list_for_each_entry(next,
&report->field_entry_list,
list) {
/*
* the priority of our element is strictly higher
* than the next one, insert it before
*/
if (entry->priority > next->priority) {
list_add_tail(&entry->list, &next->list);
return;
}
}
/* lowest priority score: insert at the end */
list_add_tail(&entry->list, &report->field_entry_list);
}
static void hid_report_process_ordering(struct hid_device *hid,
struct hid_report *report)
{
struct hid_field *field;
struct hid_field_entry *entries;
unsigned int a, u, usages;
unsigned int count = 0;
/* count the number of individual fields in the report */
for (a = 0; a < report->maxfield; a++) {
field = report->field[a];
if (field->flags & HID_MAIN_ITEM_VARIABLE)
count += field->report_count;
else
count++;
}
/* allocate the memory to process the fields */
entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
if (!entries)
return;
report->field_entries = entries;
/*
* walk through all fields in the report and
* store them by priority order in report->field_entry_list
*
* - Var elements are individualized (field + usage_index)
* - Arrays are taken as one, we can not chose an order for them
*/
usages = 0;
for (a = 0; a < report->maxfield; a++) {
field = report->field[a];
if (field->flags & HID_MAIN_ITEM_VARIABLE) {
for (u = 0; u < field->report_count; u++) {
__hid_insert_field_entry(hid, report,
&entries[usages],
field, u);
usages++;
}
} else {
__hid_insert_field_entry(hid, report, &entries[usages],
field, 0);
usages++;
}
}
}
static void hid_process_ordering(struct hid_device *hid)
{
struct hid_report *report;
struct hid_report_enum *report_enum = &hid->report_enum[HID_INPUT_REPORT];
list_for_each_entry(report, &report_enum->report_list, list)
hid_report_process_ordering(hid, report);
}
/*
* 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]);
}
}
/*
* Compute the size of a report.
*/
static size_t hid_compute_report_size(struct hid_report *report)
{
if (report->size)
return ((report->size - 1) >> 3) + 1;
return 0;
}
/*
* 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, hid_compute_report_size(report));
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 kzalloc(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);
struct hid_field *hid_find_field(struct hid_device *hdev, unsigned int report_type,
unsigned int application, unsigned int usage)
{
struct list_head *report_list = &hdev->report_enum[report_type].report_list;
struct hid_report *report;
int i, j;
list_for_each_entry(report, report_list, list) {
if (report->application != application)
continue;
for (i = 0; i < report->maxfield; i++) {
struct hid_field *field = report->field[i];
for (j = 0; j < field->maxusage; j++) {
if (field->usage[j].hid == usage)
return field;
}
}
}
return NULL;
}
EXPORT_SYMBOL_GPL(hid_find_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,
enum hid_class_request 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, enum hid_report_type 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;
int max_buffer_size = HID_MAX_BUFFER_SIZE;
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 = hid_compute_report_size(report);
if (hid->ll_driver->max_buffer_size)
max_buffer_size = hid->ll_driver->max_buffer_size;
if (report_enum->numbered && rsize >= max_buffer_size)
rsize = max_buffer_size - 1;
else if (rsize > max_buffer_size)
rsize = 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) {
hid_process_report(hid, report, 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);
static int __hid_input_report(struct hid_device *hid, enum hid_report_type type,
u8 *data, u32 size, int interrupt, u64 source, bool from_bpf,
bool lock_already_taken)
{
struct hid_report_enum *report_enum;
struct hid_driver *hdrv;
struct hid_report *report;
int ret = 0;
if (!hid)
return -ENODEV;
ret = down_trylock(&hid->driver_input_lock);
if (lock_already_taken && !ret) {
up(&hid->driver_input_lock);
return -EINVAL;
} else if (!lock_already_taken && ret) {
return -EBUSY;
}
if (!hid->driver) {
ret = -ENODEV;
goto unlock;
}
report_enum = hid->report_enum + type;
hdrv = hid->driver;
data = dispatch_hid_bpf_device_event(hid, type, data, &size, interrupt, source, from_bpf);
if (IS_ERR(data)) {
ret = PTR_ERR(data);
goto unlock;
}
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:
if (!lock_already_taken)
up(&hid->driver_input_lock);
return ret;
}
/**
* 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, enum hid_report_type type, u8 *data, u32 size,
int interrupt)
{
return __hid_input_report(hid, type, data, size, interrupt, 0,
false, /* from_bpf */
false /* lock_already_taken */);
}
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;
}
EXPORT_SYMBOL_GPL(hid_match_id);
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;
ret = hid_bpf_connect_device(hdev);
if (ret)
return 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;
}
hid_process_ordering(hdev);
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;
case BUS_VIRTUAL:
bus = "VIRTUAL";
break;
case BUS_INTEL_ISHTP:
case BUS_AMD_SFH:
bus = "SENSOR HUB";
break;
default:
bus = "<UNKNOWN>";
}
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;
hid_bpf_disconnect_device(hdev);
}
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);
/**
* hid_hw_request - send report request to device
*
* @hdev: hid device
* @report: report to send
* @reqtype: hid request type
*/
void hid_hw_request(struct hid_device *hdev,
struct hid_report *report, enum hid_class_request reqtype)
{
if (hdev->ll_driver->request)
return hdev->ll_driver->request(hdev, report, reqtype);
__hid_request(hdev, report, reqtype);
}
EXPORT_SYMBOL_GPL(hid_hw_request);
int __hid_hw_raw_request(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, enum hid_report_type rtype,
enum hid_class_request reqtype,
u64 source, bool from_bpf)
{
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
int ret;
if (hdev->ll_driver->max_buffer_size)
max_buffer_size = hdev->ll_driver->max_buffer_size;
if (len < 1 || len > max_buffer_size || !buf)
return -EINVAL;
ret = dispatch_hid_bpf_raw_requests(hdev, reportnum, buf, len, rtype,
reqtype, source, from_bpf);
if (ret)
return ret;
return hdev->ll_driver->raw_request(hdev, reportnum, buf, len,
rtype, reqtype);
}
/**
* hid_hw_raw_request - send report request to device
*
* @hdev: hid device
* @reportnum: report ID
* @buf: in/out data to transfer
* @len: length of buf
* @rtype: HID report type
* @reqtype: HID_REQ_GET_REPORT or HID_REQ_SET_REPORT
*
* Return: count of data transferred, negative if error
*
* Same behavior as hid_hw_request, but with raw buffers instead.
*/
int hid_hw_raw_request(struct hid_device *hdev,
unsigned char reportnum, __u8 *buf,
size_t len, enum hid_report_type rtype, enum hid_class_request reqtype)
{
return __hid_hw_raw_request(hdev, reportnum, buf, len, rtype, reqtype, 0, false);
}
EXPORT_SYMBOL_GPL(hid_hw_raw_request);
int __hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len, u64 source,
bool from_bpf)
{
unsigned int max_buffer_size = HID_MAX_BUFFER_SIZE;
int ret;
if (hdev->ll_driver->max_buffer_size)
max_buffer_size = hdev->ll_driver->max_buffer_size;
if (len < 1 || len > max_buffer_size || !buf)
return -EINVAL;
ret = dispatch_hid_bpf_output_report(hdev, buf, len, source, from_bpf);
if (ret)
return ret;
if (hdev->ll_driver->output_report)
return hdev->ll_driver->output_report(hdev, buf, len);
return -ENOSYS;
}
/**
* hid_hw_output_report - send output report to device
*
* @hdev: hid device
* @buf: raw data to transfer
* @len: length of buf
*
* Return: count of data transferred, negative if error
*/
int hid_hw_output_report(struct hid_device *hdev, __u8 *buf, size_t len)
{
return __hid_hw_output_report(hdev, buf, len, 0, false);
}
EXPORT_SYMBOL_GPL(hid_hw_output_report);
#ifdef CONFIG_PM
int hid_driver_suspend(struct hid_device *hdev, pm_message_t state)
{
if (hdev->driver && hdev->driver->suspend)
return hdev->driver->suspend(hdev, state);
return 0;
}
EXPORT_SYMBOL_GPL(hid_driver_suspend);
int hid_driver_reset_resume(struct hid_device *hdev)
{
if (hdev->driver && hdev->driver->reset_resume)
return hdev->driver->reset_resume(hdev);
return 0;
}
EXPORT_SYMBOL_GPL(hid_driver_reset_resume);
int hid_driver_resume(struct hid_device *hdev)
{
if (hdev->driver && hdev->driver->resume)
return hdev->driver->resume(hdev);
return 0;
}
EXPORT_SYMBOL_GPL(hid_driver_resume);
#endif /* CONFIG_PM */
struct hid_dynid {
struct list_head list;
struct hid_device_id id;
};
/**
* new_id_store - add a new HID device ID to this driver and re-probe devices
* @drv: 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, const 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 bool hid_check_device_match(struct hid_device *hdev,
struct hid_driver *hdrv,
const struct hid_device_id **id)
{
*id = hid_match_device(hdev, hdrv);
if (!*id)
return false;
if (hdrv->match)
return hdrv->match(hdev, hid_ignore_special_drivers);
/*
* hid-generic implements .match(), so we must be dealing with a
* different HID driver here, and can simply check if
* hid_ignore_special_drivers or HID_QUIRK_IGNORE_SPECIAL_DRIVER
* are set or not.
*/
return !hid_ignore_special_drivers && !(hdev->quirks & HID_QUIRK_IGNORE_SPECIAL_DRIVER);
}
static int __hid_device_probe(struct hid_device *hdev, struct hid_driver *hdrv)
{
const struct hid_device_id *id;
int ret;
if (!hdev->bpf_rsize) {
unsigned int quirks;
/* reset the quirks that has been previously set */
quirks = hid_lookup_quirk(hdev);
hdev->quirks = quirks;
/* in case a bpf program gets detached, we need to free the old one */
hid_free_bpf_rdesc(hdev);
/* keep this around so we know we called it once */
hdev->bpf_rsize = hdev->dev_rsize;
/* call_hid_bpf_rdesc_fixup will always return a valid pointer */
hdev->bpf_rdesc = call_hid_bpf_rdesc_fixup(hdev, hdev->dev_rdesc,
&hdev->bpf_rsize);
if (quirks ^ hdev->quirks)
hid_info(hdev, "HID-BPF toggled quirks on the device: %04x",
quirks ^ hdev->quirks);
}
if (!hid_check_device_match(hdev, hdrv, &id))
return -ENODEV;
hdev->devres_group_id = devres_open_group(&hdev->dev, NULL, GFP_KERNEL);
if (!hdev->devres_group_id)
return -ENOMEM;
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);
}
/*
* Note that we are not closing the devres group opened above so
* even resources that were attached to the device after probe is
* run are released when hid_device_remove() is executed. This is
* needed as some drivers would allocate additional resources,
* for example when updating firmware.
*/
if (ret) {
devres_release_group(&hdev->dev, hdev->devres_group_id);
hid_close_report(hdev);
hdev->driver = NULL;
}
return ret;
}
static int hid_device_probe(struct device *dev)
{
struct hid_device *hdev = to_hid_device(dev);
struct hid_driver *hdrv = to_hid_driver(dev->driver);
int ret = 0;
if (down_interruptible(&hdev->driver_input_lock))
return -EINTR;
hdev->io_started = false;
clear_bit(ffs(HID_STAT_REPROBED), &hdev->status);
if (!hdev->driver)
ret = __hid_device_probe(hdev, hdrv);
if (!hdev->io_started)
up(&hdev->driver_input_lock);
return ret;
}
static void hid_device_remove(struct device *dev)
{
struct hid_device *hdev = to_hid_device(dev);
struct hid_driver *hdrv;
down(&hdev->driver_input_lock);
hdev->io_started = false;
hdrv = hdev->driver;
if (hdrv) {
if (hdrv->remove)
hdrv->remove(hdev);
else /* default remove */
hid_hw_stop(hdev);
/* Release all devres resources allocated by the driver */
devres_release_group(&hdev->dev, hdev->devres_group_id);
hid_close_report(hdev);
hdev->driver = NULL;
}
if (!hdev->io_started)
up(&hdev->driver_input_lock);
}
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(const struct device *dev, struct kobj_uevent_env *env)
{
const 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;
}
const 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);
}
hdev->id = atomic_inc_return(&id);
/* 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, hdev->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);
kref_init(&hdev->ref);
ret = hid_bpf_device_init(hdev);
if (ret)
goto out_err;
return hdev;
out_err:
hid_destroy_device(hdev);
return ERR_PTR(ret);
}
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;
}
hid_free_bpf_rdesc(hdev);
kfree(hdev->dev_rdesc);
hdev->dev_rdesc = NULL;
hdev->dev_rsize = 0;
hdev->bpf_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_bpf_destroy_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);
#ifdef CONFIG_HID_BPF
static struct hid_ops __hid_ops = {
.hid_get_report = hid_get_report,
.hid_hw_raw_request = __hid_hw_raw_request,
.hid_hw_output_report = __hid_hw_output_report,
.hid_input_report = __hid_input_report,
.owner = THIS_MODULE,
.bus_type = &hid_bus_type,
};
#endif
static int __init hid_init(void)
{
int ret;
ret = bus_register(&hid_bus_type);
if (ret) {
pr_err("can't register hid bus\n");
goto err;
}
#ifdef CONFIG_HID_BPF
hid_ops = &__hid_ops;
#endif
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)
{
#ifdef CONFIG_HID_BPF
hid_ops = NULL;
#endif
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_DESCRIPTION("HID support for Linux");
MODULE_LICENSE("GPL");
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