Quelle  quicki2c-hid.c   Sprache: C

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (c) 2024 Intel Corporation */

#include <linux/hid.h>
#include <linux/input.h>
#include <linux/pm_runtime.h>

#include "quicki2c-dev.h"
#include "quicki2c-hid.h"
#include "quicki2c-protocol.h"

/**
 * quicki2c_hid_parse() - HID core parse() callback
 *
 * @hid: HID device instance
 *
 * This function gets called during call to hid_add_device
 *
 * Return: 0 on success and non zero on error.
 */
static int quicki2c_hid_parse(struct hid_device *hid)
{
 struct quicki2c_device *qcdev = hid->driver_data;

 if (qcdev->report_descriptor)
  return hid_parse_report(hid, qcdev->report_descriptor,
     le16_to_cpu(qcdev->dev_desc.report_desc_len));

 dev_err_once(qcdev->dev, "invalid report descriptor\n");
 return -EINVAL;
}

static int quicki2c_hid_start(struct hid_device *hid)
{
 return 0;
}

static void quicki2c_hid_stop(struct hid_device *hid)
{
}

static int quicki2c_hid_open(struct hid_device *hid)
{
 return 0;
}

static void quicki2c_hid_close(struct hid_device *hid)
{
}

static int quicki2c_hid_raw_request(struct hid_device *hid,
        unsigned char reportnum,
        __u8 *buf, size_t len,
        unsigned char rtype, int reqtype)
{
 struct quicki2c_device *qcdev = hid->driver_data;
 int ret = 0;

 ret = pm_runtime_resume_and_get(qcdev->dev);
 if (ret)
  return ret;

 switch (reqtype) {
 case HID_REQ_GET_REPORT:
  ret = quicki2c_get_report(qcdev, rtype, reportnum, buf, len);
  break;
 case HID_REQ_SET_REPORT:
  ret = quicki2c_set_report(qcdev, rtype, reportnum, buf, len);
  break;
 default:
  dev_err(qcdev->dev, "Not supported request type %d\n", reqtype);
  break;
 }

 pm_runtime_mark_last_busy(qcdev->dev);
 pm_runtime_put_autosuspend(qcdev->dev);

 return ret;
}

static int quicki2c_hid_power(struct hid_device *hid, int lvl)
{
 return 0;
}

static struct hid_ll_driver quicki2c_hid_ll_driver = {
 .parse = quicki2c_hid_parse,
 .start = quicki2c_hid_start,
 .stop = quicki2c_hid_stop,
 .open = quicki2c_hid_open,
 .close = quicki2c_hid_close,
 .power = quicki2c_hid_power,
 .raw_request = quicki2c_hid_raw_request,
};

/**
 * quicki2c_hid_probe() - Register HID low level driver
 *
 * @qcdev: point to quicki2c device
 *
 * This function is used to allocate and add HID device.
 *
 * Return: 0 on success, non zero on error.
 */
int quicki2c_hid_probe(struct quicki2c_device *qcdev)
{
 struct hid_device *hid;
 int ret;

 hid = hid_allocate_device();
 if (IS_ERR(hid))
  return PTR_ERR(hid);

 hid->ll_driver = &quicki2c_hid_ll_driver;
 hid->bus = BUS_PCI;
 hid->dev.parent = qcdev->dev;
 hid->driver_data = qcdev;
 hid->version = le16_to_cpu(qcdev->dev_desc.version_id);
 hid->vendor = le16_to_cpu(qcdev->dev_desc.vendor_id);
 hid->product = le16_to_cpu(qcdev->dev_desc.product_id);
 snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X", "quicki2c-hid",
   hid->vendor, hid->product);

 ret = hid_add_device(hid);
 if (ret) {
  hid_destroy_device(hid);
  return ret;
 }

 qcdev->hid_dev = hid;

 return 0;
}

/**
 * quicki2c_hid_remove() - Destroy HID device
 *
 * @qcdev: point to quicki2c device
 *
 * Return: 0 on success, non zero on error.
 */
void quicki2c_hid_remove(struct quicki2c_device *qcdev)
{
 hid_destroy_device(qcdev->hid_dev);
}

/**
 * quicki2c_hid_send_report() - Send HID input report data to HID core
 *
 * @qcdev: point to quicki2c device
 * @data: point to input report data buffer
 * @data_len: the length of input report data
 *
 * Return: 0 on success, non zero on error.
 */
int quicki2c_hid_send_report(struct quicki2c_device *qcdev,
        void *data, size_t data_len)
{
 int ret;

 ret = hid_input_report(qcdev->hid_dev, HID_INPUT_REPORT, data, data_len, 1);
 if (ret)
  dev_err(qcdev->dev, "Failed to send HID input report, ret = %d.\n", ret);

 return ret;
}