blob: b0af2be948952c645222f04cbec2d70d7a326032 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Helpers for ChromeOS HID Vivaldi keyboards
*
* Copyright (C) 2022 Google, Inc
*/
#include <linux/export.h>
#include <linux/hid.h>
#include <linux/input/vivaldi-fmap.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include "hid-vivaldi-common.h"
#define MIN_FN_ROW_KEY 1
#define MAX_FN_ROW_KEY VIVALDI_MAX_FUNCTION_ROW_KEYS
#define HID_VD_FN_ROW_PHYSMAP 0x00000001
#define HID_USAGE_FN_ROW_PHYSMAP (HID_UP_GOOGLEVENDOR | HID_VD_FN_ROW_PHYSMAP)
/**
* vivaldi_feature_mapping - Fill out vivaldi keymap data exposed via HID
* @hdev: HID device to parse
* @field: HID field to parse
* @usage: HID usage to parse
*
* Note: this function assumes that driver data attached to @hdev contains an
* instance of &struct vivaldi_data at the very beginning.
*/
void vivaldi_feature_mapping(struct hid_device *hdev,
struct hid_field *field, struct hid_usage *usage)
{
struct vivaldi_data *data = hid_get_drvdata(hdev);
struct hid_report *report = field->report;
u8 *report_data, *buf;
u32 report_len;
unsigned int fn_key;
int ret;
if (field->logical != HID_USAGE_FN_ROW_PHYSMAP ||
(usage->hid & HID_USAGE_PAGE) != HID_UP_ORDINAL)
return;
fn_key = usage->hid & HID_USAGE;
if (fn_key < MIN_FN_ROW_KEY || fn_key > MAX_FN_ROW_KEY)
return;
if (fn_key > data->num_function_row_keys)
data->num_function_row_keys = fn_key;
report_data = buf = hid_alloc_report_buf(report, GFP_KERNEL);
if (!report_data)
return;
report_len = hid_report_len(report);
if (!report->id) {
/*
* hid_hw_raw_request() will stuff report ID (which will be 0)
* into the first byte of the buffer even for unnumbered
* reports, so we need to account for this to avoid getting
* -EOVERFLOW in return.
* Note that hid_alloc_report_buf() adds 7 bytes to the size
* so we can safely say that we have space for an extra byte.
*/
report_len++;
}
ret = hid_hw_raw_request(hdev, report->id, report_data,
report_len, HID_FEATURE_REPORT,
HID_REQ_GET_REPORT);
if (ret < 0) {
dev_warn(&hdev->dev, "failed to fetch feature %d\n",
field->report->id);
goto out;
}
if (!report->id) {
/*
* Undo the damage from hid_hw_raw_request() for unnumbered
* reports.
*/
report_data++;
report_len--;
}
ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT, report_data,
report_len, 0);
if (ret) {
dev_warn(&hdev->dev, "failed to report feature %d\n",
field->report->id);
goto out;
}
data->function_row_physmap[fn_key - MIN_FN_ROW_KEY] =
field->value[usage->usage_index];
out:
kfree(buf);
}
EXPORT_SYMBOL_GPL(vivaldi_feature_mapping);
static ssize_t function_row_physmap_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct hid_device *hdev = to_hid_device(dev);
struct vivaldi_data *data = hid_get_drvdata(hdev);
return vivaldi_function_row_physmap_show(data, buf);
}
static DEVICE_ATTR_RO(function_row_physmap);
static struct attribute *vivaldi_sysfs_attrs[] = {
&dev_attr_function_row_physmap.attr,
NULL
};
static umode_t vivaldi_is_visible(struct kobject *kobj, struct attribute *attr,
int n)
{
struct hid_device *hdev = to_hid_device(kobj_to_dev(kobj));
struct vivaldi_data *data = hid_get_drvdata(hdev);
if (!data->num_function_row_keys)
return 0;
return attr->mode;
}
static const struct attribute_group vivaldi_attribute_group = {
.attrs = vivaldi_sysfs_attrs,
.is_visible = vivaldi_is_visible,
};
const struct attribute_group *vivaldi_attribute_groups[] = {
&vivaldi_attribute_group,
NULL,
};
EXPORT_SYMBOL_GPL(vivaldi_attribute_groups);
MODULE_LICENSE("GPL");