linux-imx

/*

 * drivers/input/tablet/wacom_sys.c

 *

 *  USB Wacom tablet support - system specific code

 */

​

/*

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 */

​

#include "wacom_wac.h"

#include "wacom.h"

#include <linux/input/mt.h>

​

#define WAC_MSG_RETRIES     5

#define WAC_CMD_RETRIES     10

​

#define DEV_ATTR_RW_PERM (S_IRUGO | S_IWUSR | S_IWGRP)

#define DEV_ATTR_WO_PERM (S_IWUSR | S_IWGRP)

#define DEV_ATTR_RO_PERM (S_IRUSR | S_IRGRP)

​

static int wacom_get_report(struct hid_device *hdev, u8 type, u8 *buf,

                size_t size, unsigned int retries)

{

    int retval;

​

    do {

        retval = hid_hw_raw_request(hdev, buf[0], buf, size, type,

                HID_REQ_GET_REPORT);

    } while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries);

​

    if (retval < 0)

        hid_err(hdev, "wacom_get_report: ran out of retries "

            "(last error = %d)\n", retval);

​

    return retval;

}

​

static int wacom_set_report(struct hid_device *hdev, u8 type, u8 *buf,

                size_t size, unsigned int retries)

{

    int retval;

​

    do {

        retval = hid_hw_raw_request(hdev, buf[0], buf, size, type,

                HID_REQ_SET_REPORT);

    } while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries);

​

    if (retval < 0)

        hid_err(hdev, "wacom_set_report: ran out of retries "

            "(last error = %d)\n", retval);

​

    return retval;

}

​

static void wacom_wac_queue_insert(struct hid_device *hdev,

                   struct kfifo_rec_ptr_2 *fifo,

                   u8 *raw_data, int size)

{

    bool warned = false;

​

    while (kfifo_avail(fifo) < size) {

        if (!warned)

            hid_warn(hdev, "%s: kfifo has filled, starting to drop events\n", __func__);

        warned = true;

​

        kfifo_skip(fifo);

    }

​

    kfifo_in(fifo, raw_data, size);

}

​

static void wacom_wac_queue_flush(struct hid_device *hdev,

                  struct kfifo_rec_ptr_2 *fifo)

{

    while (!kfifo_is_empty(fifo)) {

        u8 buf[WACOM_PKGLEN_MAX];

        int size;

        int err;

​

        size = kfifo_out(fifo, buf, sizeof(buf));

        err = hid_report_raw_event(hdev, HID_INPUT_REPORT, buf, size, false);

        if (err) {

            hid_warn(hdev, "%s: unable to flush event due to error %d\n",

                 __func__, err);

        }

    }

}

​