linux-imx

// SPDX-License-Identifier: GPL-2.0+

/*

 *  HID driver for Google Hammer device.

 *

 *  Copyright (c) 2017 Google Inc.

 *  Author: Wei-Ning Huang <wnhuang@google.com>

 */

​

/*

 * 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 <linux/acpi.h>

#include <linux/hid.h>

#include <linux/leds.h>

#include <linux/mfd/cros_ec.h>

#include <linux/mfd/cros_ec_commands.h>

#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/pm_wakeup.h>

#include <asm/unaligned.h>

​

#include "hid-ids.h"

​

/*

 * C(hrome)B(ase)A(ttached)S(witch) - switch exported by Chrome EC and reporting

 * state of the "Whiskers" base - attached or detached. Whiskers USB device also

 * reports position of the keyboard - folded or not. Combining base state and

 * position allows us to generate proper "Tablet mode" events.

 */

struct cbas_ec {

    struct device *dev; /* The platform device (EC) */

    struct input_dev *input;

    bool base_present;

    struct notifier_block notifier;

};

​

static struct cbas_ec cbas_ec;

static DEFINE_SPINLOCK(cbas_ec_lock);

static DEFINE_MUTEX(cbas_ec_reglock);

​

static bool cbas_parse_base_state(const void *data)

{

    u32 switches = get_unaligned_le32(data);

​

    return !!(switches & BIT(EC_MKBP_BASE_ATTACHED));

}

​

static int cbas_ec_query_base(struct cros_ec_device *ec_dev, bool get_state,

                  bool *state)

{

    struct ec_params_mkbp_info *params;

    struct cros_ec_command *msg;

    int ret;

​

    msg = kzalloc(sizeof(*msg) + max(sizeof(u32), sizeof(*params)),

              GFP_KERNEL);

    if (!msg)

        return -ENOMEM;

​